Monday, 11 November 2019

Art of Creative Thinking

                     Art of Creative Thinking

                                 

                                           Dr KS Dhillon



What is creative thinking?


‘To create is always to do something new’.
                                                                   Martin Luther

“Creative thinking is not a talent, it is a skill that can be learnt.
It empowers people by adding strength to their natural abilities
which improves teamwork, productivity and where appropriate
profits”
                                                                                 Edward de Bono

The word creativity originated from the Latin term creō, which means to create or to make. It refers to the ability to generate new ideas and find original and useful solutions to problems [1]. 
Creative thinking is often referred to as, ‘thinking out of the box’, ‘lateral thinking’, or ‘divergent thinking’. In simple terms, it means looking at something in a new way. It is the ability to think differently and to perceive patterns that are not obvious. Creative thinking makes a person see things from a new angle or perspective.

Creative thinking allows a person to explore connections, meet new challenges and seek original, fresh and unusual solutions.

What is the need for creative thinking? 

Creative thinking has many advantages. Creative thinking helps a person to become a more confident, stronger, self-reliant and happier person. Creative thinking adds value not only to one’s life but also the life of others around. Open-minded thinking helps a person to explore new thoughts and ideas. Hidden talents surface, which allows a person to discover new opportunities, when creative thinking is adopted. There is no dead-end road for creative thinkers. There are endless opportunities to explore new challenges. Creative thinking gives a person a reason to wake up every morning and see what others cannot see.

The experiences gained through creative thinking makes it easier to handle difficult and challenging situations that come around. Creative thinking also makes a person happier and liked by people around.

How to enhance creative thinking skills?


Some believe that creative thinking techniques are based on experience. In 1996 this is what Steve Jobs had to say about creative thinking.

“Creativity is just connecting things. When you ask creative people how they did something, they feel a little guilty because they didn’t really do it, they just saw something. It seemed obvious to them after a while. That’s because they were able to connect experiences they’ve had and synthesize new things. And the reason they were able to do that was that they’ve had more experiences or they have thought more about their experiences than other people. Unfortunately, that’s too rare a commodity. A lot of people in our industry haven’t had very diverse experiences. So they don’t have enough dots to connect, and they end up with very linear solutions without a broad perspective on the problem”.

There are several ways in which creative thinking skills can be enhanced.

1.Counterfactual thinking


The term counterfactual literally means contrary to the facts. Counterfactual thinking is creating possible alternatives to life events that have already occurred which in fact is contrary to what actually happened. In counterfactual thinking thoughts such as ‘what if’ and ‘if I had only done that’ run through a person’s mind and the person wonders how things could have turned out differently. Counterfactual thoughts include things that could never happen in reality because they pertain to events that have occurred in the past.

A counterfactual thought occurs when a person alters a factual prior event and then goes on to assess the consequences of that change. A person imagines how the outcome could have been different if the antecedents which led to the event were different. For example, a nurse whose patient died while undergoing treatment in the ward may reflect upon how things could have turned out differently by imagining how some of the factors could have been different for a different outcome. The person would think that if she had given closer attention to the patient’s medical condition the patient may not have died.

There are two components in counterfactual thinking. The first is the activation portion and the second is content. The activation portion is when we allow the counterfactual thought to enter into our conscious thought and the content portion creates the end scenario for the thought that has entered the conscious[2].

Counterfactual thinking has both positive and negative consequences for the individual but the net result is an overall benefit for the individual.

Why do we allow ourselves to think of alternatives that can be beneficial or harmful to us? Many believe that humans tend to think of such counterfactual ideas in the presence of exceptional circumstances that led to an event which could have been avoided in the first place. Another reason why we use counterfactual thoughts is because we are close to an alternative outcome with positive outcomes [2].

Counterfactual thinking has a preparative function that helps people avoid past blunders and it makes a person feel better[3]. Counterfactual thinking is known to boost creativity for short periods of time.



2.Discovery-oriented behavior


According to Wertheimer [4], the function of thinking is not just to solve actual problems but to discover, envisage and go into deeper questions. In most great discoveries a certain question is often found. Envisaging and putting forward a productive question is a greater achievement than the solution of a question that has been set.

Research shows that real-world problem finding measure is predictive of creative thinking and real-world problem-finding measure is the most valuable predictor of creative potential [5].
Real-world problem finding is useful in enhancing creative thinking. For example, the nursing manager in the hospital ward can ask the nursing staff to think of as many different problems as possible, in their ward and come up with as many solutions as possible.

Creative thinkers don’t sit back and think of cut-and-dry end goals, they instead examine the problem from different angles before beginning to do the work.

3.Interpersonal distance and creativity


When there is a creative block, abstaining from a task is known to be useful. Now there is evidence which shows that creating “psychological” distance is also useful.

Jia et al [6] studied the effect of spatial distance on creative cognition and insight problem-solving. They were able to show that when a creative task is portrayed as originating from afar rather than a close location, individuals were able to provide more creative responses as well as perform better on problem-solving tasks that required creative insight. Individuals in their study were able to solve twice as many insight problems when they were asked to think about the source of the task which is distant, rather than closeby.

Förster et al [7] carried out six studies to investigate how and whether distant future time perspective promotes abstract thinking and at the same time impedes concrete thinking, by altering the level at which an individual’s mental representations are construed. They found that individuals who imagined themselves engaging in tasks a year later as compared to the next day performed better on a series of insight tasks. They also found that a distant perspective improved the creative generation of abstract solutions.

According to construal level theory (CLT), the distance of an individual from objects and events determines how abstractly the individual will represent or construe the objects and events. Whether events or objects are construed at lower or higher levels of abstraction would depend on conceptual differences as well as perceptual differences [8].

The contents of more abstract, higher-level construals consists of a summary of the given information about objects and events, whereas the content of lower-level construals consists of contextual and readily observable features [8]. Higher-level construals involve broad and global processing of information whereas lower-level construals involve narrow and localized processing of information[8]. The main tenet of CLT is that increasing the distance of an individual from objects and events is associated with more abstract construals. Creativity increases as the spatial distance increases.

One has to try to imagine that one’s creative task is disconnected and distant from one’s current position or location. This will make the problem more accessible and it can encourage higher-level thinking.

4.Embracing absurdity


Research shows that reading and or experiencing something unreal or absurd can boost pattern recognition and creative thinking. The mind is always trying to make sense of the things that a person sees. Absurd and unreal things put the mind in overdrive for short periods of time while the mind works out what it is looking for [9].

Proulx and Heine [9] were able to show that novel patterns of association learning could be enhanced by unrelated meaning threats. They found that the ‘cognitive mechanisms responsible for implicitly learning patterns are enhanced by the presence of a meaning threat’ [9]. Meaning threats whatever their source motivate people to seek out meaning somewhere else. Meaning threats can be to an individual’s self-esteem, threats to their political worldview, threats to their sense of situational certainty, threats to their existence or threats to their goal attainment [9].

Reading interesting absurd short stories and seeing absurd art can provide inspiration to individuals.

5. Let your mind wander


There is a link between mind-wandering and crucial parts of our daily lives, including affect, learning and job productivity. Mind-wandering is limited in the morning and it increases throughout the morning and peaks at midday. It decreases through the afternoon and peaks again in the evening [10].
A wandering mind can boost creative thinking. It allows you to access new ways of processing and imagining and help you to come up with new solutions to old problems. It can inspire an individual to write new stuff and learn new languages. It is a creative minds’ ultimate asset.

A wandering mind encourages inquisitiveness which in turn increases the desire for information and knowledge. It also stretches one's imagination and lays the fountain for creativity. The newfound creativity opens up new avenues of thinking, planning, preparing and ultimately doing things.
Self-imagination and awareness of self increases when the mind wanders.

Self-imagination allows the transfer of short term memory to long term memory by concentrating on the meaning of the information. Self-imagination helps with retrieval of memory and it also brings about a sense of self.

6. Day time naps and sleep


A nap of between 10 min to 30 min duration during the day is known to promote wakefulness and enhance performance and improve learning ability. Longer naps, on the other hand, are associated with a loss of productivity and sleep inertia. The habit of taking frequent and long naps especially among the elderly may be associated with higher morbidity and mortality [11].

Nocturnal sleep provides pivotal insights. Insight is mental restructuring which leads to a gain of knowledge which brings about qualitatively changed behavior. Sleep allows the consolidation of recent memories.

A study by Wagner et al [12] showed that sleep, by restructuring new memory and representations, facilitates extraction of explicit knowledge and insightful behaviour.

7. Conceptualize the problem in a new way


Creative people generally look at problems in a new way more often as compared to less creative people. Creative people avoid cut-and-dry end goals and they examine the problem from different angles before starting on a job. Creative individuals focus on fundamental parts of the problem and they look at a more meaningful angle of the problem which leads them to something that is original.

8. Embrace your limitations


Many believe that freedom gives you the space to be a better creator. This is not true because history shows us that most creative endeavors took place within limited environments with restricted budgets and individuals who had an abundance of talent and finances often fail to create anything original.
It is well known that creativity is not born from freedom. We have to push ourselves beyond our limits to learn a skill, absorb the rules, learn where the limits are and try to exceed them. Staying inside a box helps us think outside it by looking at light shining through the cracks in the box.
Imposing restrictions or limitations can actually boost creativity, which is the ultimate defense against a creative block. More freedom can be crippling. When we have more options than it is harder to make decisions. When we add limitations to our creative process it helps us to stay motivated and we find new ways to handle the difficulty.

Limitations challenge the way we think and it forces us to think in new ways. Creative problem solving keeps our mind sharp. Thinking of limitations makes our brain work harder and peculiar limitations push the mind to work harder.

Limitations yield more interesting results and it leads us down new paths which we may be unfamiliar with. One must avoid taking the path of least resistance and building on ideas that we already have and using all the resources available. We need to impose limitations which can boost our creativity and force us to work outside of our comfort zone.



8. Mood and creativity


“Feeling and longing are the motive forces behind all human endeavour and human creations”
                                    Albert Einstein, Religion and Science

Creativity is critical for both survival and prosperity. Hence people adapt to changing environment by generating new insights and solving problems. One of the most studied predictors of creativity is mood.

Baas et al [13] carried out a meta-analysis of 25 years of mood-creativity research. They found that positive moods produce more creativity than mood-neutral controls and there were no significant differences between negative moods and mood-neutral controls.

Moods with positive hedonic tone (e.g happiness and relaxed state) bring about greater creative performance as compared to moods with negative hedonic tone (e.g fear and sadness) or neutral mood control conditions. The reason for this is that positive hedonic tone increases cognitive flexibility and inclusiveness. Negative activating moods such as fear and anxiety are associated with lower creativity.

Moods with positive hedonic tones are associated with an increase in dopamine levels in the anterior cingulate cortex of the brain. Dopamine mediates many of the cognitive effects of positive affect. Increased levels of dopamine promote creative thinking.

Some investigators have found the opposite effect of mood on creativity. Kaufmann et al [14] in a study found that positive mood led to significantly poorer creative problem-solving performance and negative mood significantly facilitated creative problem-solving relative to induced neutral mood. They found that the poorest performance was obtained in the positive mood condition.
Overall most studies show that a positive mood is associated with creativity.

9. Exercise and creativity


There is a link between physical exercise and favorable moods and this has been well established. Various kinds of exercise such as aerobic workout, jogging, running, cycling as well as treadmill have been shown to enhance mood [15]. Steinberg et al [15] carried out a study to assess if exercise enhances creativity independently of mood. They found that mood was significantly improved by aerobic exercise as compared with a neutral video control group. They also found that there was a consistent increase in creativity with exercise. They concluded that creativity and mood improved with physical exercise independently of each other.

10. Pursue weird or different experiences


“Creativity comes from looking for the unexpected and stepping outside your own experience.” ~Masaru Ibuka

It is well known that creative people can be eccentric. History shows us that many poets and playwrights had odd behavior and this has been observed by well-known people like Plato and Aristotle. History tells us that Albert Einstein used to pick up cigarette butts from the street to get tobacco for his pipe. Howard Hughes used to spend full days on a chair in the middle of his Beverly Hills Hotel suite because he believed that the suite was germ-free. The famous German composer and critic, “Robert Schumann believed that his musical compositions were dictated to him by Beethoven and other deceased luminaries from their tombs and Charles Dickens is said to have fended off imaginary urchins with his umbrella as he walked the streets of London” [16].

Research has established that there is a connection between creativity and eccentricity. This association is often seen in individuals with schizotypal personality which is a milder version of schizotypal personality disorder.

According to Shelley Carson [18], schizotypal personality can appear in a variety of forms, some of which include magical thinking, unusual perceptual experiences, social anhedonia, and mild paranoia.

There are several studies which show that creative people tend to score higher on schizotypal surveys. Carson also found that some creative students report “magical thinking and odd perceptual experiences” such as hearing whispering voices in the wind. [18].

Schizotypal personality does not predispose an individual to creativity.  Cognitive disinhibition appears to be the underlying factor in eccentricity. Cognitive disinhibition occurs when an individual is unable to ignore irrelevant or immaterial information.

There is a large amount of data that we are bombarded with throughout the day and it is not possible to attend to all this data on a daily basis. To prevent this data from reaching our conscious awareness we all possess mental filters. One of these filters is called latent inhibition (LI). LI has been
defined by Carson and colleagues as: “the varying capacity of the brain to screen from current attentional focus stimuli previously experienced as irrelevant”[17]. Research shows that reduced LI is associated with increased vulnerability to schizophrenia. Low LI has also been found to contribute to original thinking especially in combination with high IQ.

It is well known that not everyone who’s weird is creative. This is because research shows that only individuals with low LI who have high IQ are creative [17].

Highly creative individuals and psychotic-prone individuals probably possess neurobiological similarities which are genetically determined and they present either as psychotic predisposition or as unusual creative potential.

11. Challenge your brain. 


Problem-solving is the key to creativity. The commonly used approach to creative problem solving (CPS) is the 6-diamond model [18].

The 6 steps include [19]:

  •  Mess finding: The areas of concern are identified. Ideas are generated for possible solutions. Three most critical problems are identified and one is selected for further work.
  •  Fact-finding: Careful observation is necessary while collecting information  about the problem situation. Both objective and subjective information is collected, identified and explored. 
  •  Problem finding: Look at the problem from different angles and think of other possibilities.
  •  Idea Finding: Look for a variety of ideas, alternatives, options, approaches, paths, methods and tools to select potential ideas or solutions.
  • Solution finding: Look at all the ideas in new and different ways. Consider the consequences, implications, and reactions to the ideas selected. Once the ideas have been selected and solutions found than develop an action plan.
  •  Acceptance finding: Once the action plan has been developed, think of ways to implement the action plan. Ways must be found to make the ideas and solutions more attractive, more effective, more acceptable and more beneficial. Working plan for implementation must be developed.

There has been a lot of research into the CPS process which shows that there is a need for willingness to consider alternatives, to take risks, to venture into insecure areas and to tolerate some uncertainty and ambiguity [20].

12. Chart your own path.


“Act! Action will delineate and define you.”
                                     Thomas Jefferson.

It is well known that the only person who can promote yourself is you. There is no one who will promote you or put you in the limelight unless you do it yourself. You have to sell your story yourself.

Well known people who charted their own path include Steve Job, Bill Gates, Thomas Eddison, Wright brothers, James Watt and the list goes on and on.

Only we ourselves can define and determine our destiny. We have the responsibility of managing our thoughts. Positive thinking will spur us to positive actions and productive habits. Good habits will shape a positive fruitful future.

We have to stay away from defeatist, discouraging and disillusionary thoughts and negative attitude. We have to stay away from people who belittle our dreams. You are the best person to set your own goals.

Charting our own creative path helps us open doors which we might have never known existed. Trailblazers are people who hold hands with fear and they are willing to risk venturing into the unknown rather than staying in familiar surroundings. They are willing to venture into the unknown
Nobody can discover the world for us, we have to discover it ourselves.



Conclusion

Creative thinking refers to one’s ability to generate new ideas and find original and useful solutions to problems. Sometimes it is referred to as, ‘thinking out of the box’, ‘lateral thinking’, or ‘divergent thinking’. It is the ability to think differently and to perceive patterns that are not obvious. It makes a person see things from a new angle or perspective and it allows a person to explore connections, meet new challenges and seek original, fresh and unusual solutions.

Creative thinking helps a person to become a more confident, stronger, self-reliant and happier person. Creative thinking adds value not only to one’s life but also the life of others around.
There are several ways in which creative thinking can be enhanced and these are explored in some detail in this article.

References


  1. Ritter, S. M. & Mostert, N. Enhancement of Creative Thinking Skills Using a Cognitive-Based Creativity Training. J Cogn Enhanc. 2017; 1, 243–253.
  2. Roese N. Counterfactual thinking. Psychological Bulletin. 1997; 121 (1): 133–148.
  3. Olson JM & Roese N J. Relative deprivation and counterfactual thinking. In Walker, I. and Smith, H. J. (Eds.). Relative deprivation: Specification, development, and integration. 2002. pp.  265–287. Cambridge, UK: Cambridge University Press.
  4. Wertheimer, M. Productive thinking.1945 New York: Harper & Row.
  5. Okuda SM, Runco MA, Berger E. Creativity and the finding and solving real-world problems. J of Psychoeducational assessment. 1991; 9: 45-53.
  6. Jia L, Edward R, Hirt, Karpen SC. Lessons from a Faraway land: The effect of spatial distance on creative cognition. Journal of Experimental Social Psychology. 2009; 45(5):1127-1131
  7. Förster J, Friedman RS, & Liberman N. Temporal Construal Effects on Abstract and Concrete Thinking: Consequences for Insight and Creative Cognition. Journal of Personality and Social Psychology. 2004; 87(2), 177-189.
  8. Henderson MD, Wakslak CJ, Fujita K and Rohrbach J. Construal Level Theory and Spatial Distance Implications for Mental Representation, Judgment, and Behavior. Social Psychology 2011; Vol. 42(3):165–173.
  9. Proulx T, Heine SJ. Connections from Kafka: exposure to meaning threats improves implicit learning of an artificial grammar. Psychol Sci. 2009 Sep;20(9):1125-31.
  10. Smith, Gabriel King, et al. “Mind-wandering rates fluctuate across the day: evidence from an experience-sampling study.” Cognitive research: principles and implications. 2018; 3 (1): 54.
  11. Dhand R, Sohal H. Good sleep, bad sleep! The role of daytime naps in healthy adults. Curr Opin Pulm Med. 2006 Nov;12(6):379-82.
  12. Wagner U, Gais S, Haider H, Verleger R, Born J. Sleep inspires insight. Nature. 2004 Jan 22;427(6972):352-5.
  13. Baas M, De Dreu CK, Nijstad BA. A meta-analysis of 25 years of mood-creativity research: hedonic tone, activation, or regulatory focus? Psychol Bull. 2008 Nov;134(6):779-806.
  14. Kaufmann G and & Vosburg SK. (1997). Paradoxical mood effects on creative problem-solving. Cognition and Emotion. 1997; 11: 151-170.
  15. Steinberg H,Sykes EA, Moss T,Lowery S,LeBoutillier N,Dewey A. Exercise enhances creativity independently of mood. Br J Sports Med.1997;31:240-245.
  16. Shelley Carson. Your Creative Brain: Seven Steps to Maximize Imagination, Productivity, and Innovation in Your Life. 2010, Jossey-Bass publisher, Harvard University.
  17. Carson SH, Peterson JB, Higgins DM. Decreased latent inhibition is associated with increased creative achievement in high-functioning individuals. J Pers Soc Psychol. 2003 Sep;85(3):499-506.
  18. Courger J.D. (1995) Creative Problem Solving and Opportunity Finding. 1995 Boyd and Fraser publishing company.
  19. Vidal R. Creativity for OperationalResearchers. Investigacao Operacional. 2005;25:1-24.
  20. Parnes, S.J. (1997) Optimize the Magic of your Mind, NY: Bearly Limited.


Monday, 7 October 2019

Long Term Outcome of Treatment of Subaxial Cervical Spine Fractures

              Long Term Outcome of Treatment of Subaxial Cervical Spine Fractures



                                                          Dr KS Dhillon



Classification of subaxial cervical spine fractures

The widely used classification for lower cervical spine injuries is the one by the AO group. It divides lower cervical spine injuries into 3 types i.e type A, B, C based on the trauma mechanism.

A: compression
B: distraction
C: rotation

Type A compression injuries are further subdivided into type:
 A.1  =  impaction
 A.2  =  split
 A.3  =  burst.

Type B distraction injuries are further subdivided into:
 B.1  =  posterior distraction with vertebral body intact
 B.2  =  posterior distraction + fracture of the vertebral body
 B.3  =  anterior distraction + hyperextension.

Type C rotation injuries are subdivided into:
C.1  =  unilateral facet fracture-dislocation
C.2  =  unilateral facet dislocation
C.3  =  rotational shear injury of the joint mass.

To remedy a lack of consensus on the classification of lower cervical spine injuries the Subaxial Injury Classification (SLIC) Scale was created [1]. This classification takes into account morphology; status of the disco-ligamentous complex and neurological assessment.



Table 1. Subaxial Injury Classification (SLIC) scale.
   
Morphology                                                                                                  Points
No abnormality                                                                                               0
Compression + burst                                                                                1 + 1  =  2
Distraction (e.g., facet perch or hyperextension)                                            3
Rotation or translation (e.g., facet dislocation, unstable teardrop,
or advanced-stage flexion-compression injury)                                              4

Disc-ligamentous complex
Intact                                                                                                               0
Indeterminate (e.g., isolated interspinous widening or MRI signal
change only)                                                                                                    1
Disrupted (e.g., widening of the anterior disk space or facet perch
or dislocation)                                                                                                  2

Neurological status
Intact                                                                                                              0
Root injury                                                                                                      1
Complete cord injury                                                                                      2
Incomplete cord injury                                                                                    3
Continuous cord compression (neuro-modifier in the setting of a
neurological deficit)                                                                                     + 1

Based on the above parameters, scores are assigned to each injury. Patients with a score lower than 4 will need nonsurgical treatment and patients with scores higher than 4 will require surgical treatment. Patients with a score of 4 can be treated surgically or nonsurgically depending on the experience of the surgeon.




Treatment of subaxial cervical spine fractures

Unfortunately, there is insufficient evidence to recommend treatment standards and there is also insufficient evidence to recommend treatment guidelines for subaxial cervical spine injuries [2]. The main principles of treatment include decompression of compressed neurological structures, restoration of vertebral column integrity, prevention and management of complications, and facilitation of rehabilitation [3].

Subaxial Injury Classification (SLIC) Scale has been introduced to help in decision making for treatment of subaxial injuries [1]. Generally, patients with a score lower than 4 are treated nonsurgically while patients with scores higher than 4 are treated with surgery. Patients with a score of 4 can be treated surgically or nonsurgically depending on the experience of the surgeon.
Many patients with cervical spine injuries can be treated nonoperatively. Options for conservative treatment include the use of a cervical orthosis or rigid stabilization with a halo jacket.

In patients with displaced cervical spine injury, a closed reduction can be carried out. It is safe to treat displaced subaxial fracture and subaxial subluxations and dislocations, by traction [3].

Lee et al [4] carried out a study involving 210 patients with unilateral and bilateral facet dislocations. They found that rapid traction under sedation using weights up to 150 pounds was safer than carrying out manipulation under anesthesia. They also found that early reduction of the dislocation in patients with neurological deficit gave them the best chance of neurological recovery.

Surgery is usually indicated in patients when a close reduction has failed, in patients with unstable injuries and when there is bilateral facet dislocation of more than 25% or 11°. Progressive neurological deterioration would be another indication for surgery. Kyphosis of 30° or more or loss of vertebral height of more than 50% is often associated with a high incidence of late complications, and this situation may warrant surgical intervention. Late instability and severe post-traumatic kyphosis may warrant surgical intervention [3].

In patients with partial neurological injury, early surgical intervention is usually recommended. There is some evidence that early surgical intervention (less than 24 hours) is safe and effective. Neurological recovery can also occur in some patients who have delayed decompression [4,5].
Some have claimed that 70% of patients with partial spinal cord injury improve one grade or more (American Spinal Injuries Association, International Medical Society of Paraplegia grades) if the surgery is carried within 6 hours after the injury [7]. When surgery is carried out after 6 hours only 12% of the patients show improvement. In patients with a complete spinal cord injury, the chances of neurological recovery is poor.

Decompression and/or stabilized of the cervical spine can be carried out via the anterior, posterior or a combination of both approaches, depending on the type of injury. The clinical success rates are higher with the anterior approach through the anterior approach is biomechanically inferior to the posterior approach [3].

Long term outcome of cervical spine injury treatment

There is a dearth of literature on the long term outcome of management of cervical spine injuries. The largest study with a long term follow up is the one by Fredø et al [8]. They followed up 256 patients with subaxial cervical spine injuries who were treated surgically. The surgical approach was anterior in 69% of the patients, posterior in 22% and combined in 9 % of the patients.
The mean follow-up period was 3.1 years with a range of 0.5–9.0 years. None of their patients had neurological deterioration after the surgery.

In patients who were operated within 24 hours, 48.8% showed improvement of their neurological grades, whereas in patients operated after 24 hours 53.1% showed improvement in their neurological grades. The improvement in AIS (American Spinal Injury Association impairment scale) grades between the two groups were not significantly different (p = 0.442). Of the patients with preoperative radiculopathy, 11 % of the patients continued to have radicular symptoms. There were four patients who developed radiculopathy after surgery, three of these patients were asymptomatic at follow-up.
Neck pain was assessed using the Visual Analog Scale (VAS). They found that the median VAS score for neck pain was 1 (range 0–10). Eighty percent of the patients had VAS scores ≤3, 15 % had VAS scores 4–6, and 5 % had VAS scores ≥7. There was no significant association between the surgical approach and neck pain [8].

They found that 26% of the patients had no neck stiffness, 63% had mild neck stiffness and 11% had severe neck stiffness. Neck stiffness was more common in patients who had fusion with posterior screw fixation.

Six percent of patients sustained hoarseness and 9% developed dysphagia after surgery. Of the 256 patients who were followed up with cervical CT scans, 98.4 % had a stable fusion, 0.4 % had a secondary loss of alignment, and in 1.2 % of the patients, there was loosening or fracture of their fixation device[8]. In this study, the surgical mortality(death within 30 days after surgery) was 2.3 %.
Koller et al. [9] carried out a retrospective review of 28 patients who had anterior cervical decompression, fusion, and plating (ACDFP) for unstable subaxial injuries without neurological deficit, to assess the mid- to long-term outcome. The mean follow up period was 5.5 years (range16–128 months). The self-rated clinical outcome was excellent or good in 81% of patients and moderate or poor in 19% of the patients.

Construct failure was seen in 31% of cases.  The fusion rate was 88.5%.  Adjacent-level degeneration progression was significantly influenced by a decreased plate-to-disc-distance. The motion of adjacent level intervertebral space was not altered due to the adjacent fusion, but it was reduced in the presence of advanced adjacent level degeneration.


Conclusion

There is a dearth of literature on the long term outcome of management of cervical spine injuries. The largest study with a long term follow up is the one by Fredø et al [8]. They followed up 256 patients with subaxial cervical spine injuries who were treated surgically. The mean follow-up period was 3.1 years with a range of 0.5–9.0 years. They obtained stable fusion in 98.4% of the patients, 0.4 % had a secondary loss of alignment, and in 1.2 % of the patients, there was implant failure. The surgical mortality (death within 30 days after surgery) was 2.3 %.

Koller et al. [9] carried out a small retrospective review of 28 patients who had anterior cervical decompression, fusion, and plating (ACDFP) for unstable subaxial injuries without neurological deficit, to assess the mid- to long-term outcome. The mean follow up period was 5.5 years (range16–128 months). Their results were not as good as the ones reported by Fredø et al [8]. Construct failure rates were very high with an incidence of 31%. Their fusion rates were lower at 88.5%.

To date, no other studies on the long term outcome of management of subaxial cervical spine injuries, have been published.

References


  1. Dvorak MF, Fisher CG, Fehlings MG, Rampersaud YR, Oner FC, Aarabi B, et al. The surgical approach to subaxial cervical spine injuries: an evidence-based algorithm based on the SLIC classification system. Spine (Phila Pa 1976) 2007;32(23):2620–9.
  2. Hadley MN, Walters BC, Grabb PA, Oyesiku NM, Przybylski GJ, Resnick DK, Ryken TC. Treatment of subaxial cervical spinal injuries. Neurosurgery. 2002 Mar;50(3 Suppl): S156-65.
  3. O'Dowd JK. Basic principles of management for cervical spine trauma. Eur Spine J. 2010 Mar; 19(Suppl 1): 18–22.
  4. Lee AS, MacLean JC, Newton DA. Rapid traction for reduction of cervical spine dislocations. J Bone Joint Surg Br. 1994 May;76(3):352-6.
  5. La Rosa G, Conti A, Cardali S, Cacciola F, Tomasello F. Does early decompression improve neurological outcome of spinal cord injured patients? Appraisal of the literature using a meta-analytical approach. Spinal Cord 2004;42:503-12.
  6. Fehlings MG, Perrin RG. The role and timing of early decompression for cervical spinal cord injury: Update with a review of recent clinical evidence. Injury 2005;36 Suppl 2:B13-26.
  7. Fehlings M, Aarabi B, Dvorak M, et al. (2008) A prospective multicenter trial to evaluate the role and timing of decompression in patients with cervical spinal cord injury: initial one-year results of the STASCIS study. Paper presented at the AANS meeting in Chicago.
  8. Fredø HL, Rizvi SAM, Rezai M, Rønning P, Lied B and Helseth E. Complications and long-term outcomes after open surgery for traumatic subaxial cervical spine fractures: a consecutive series of 303 patients. BMC Surg. 2016 Aug 15;16(1):56.
  9. Koller H, Reynolds J, Zenner J, Forstner R, Hempfing A, Maislinger I, Kolb K, Tauber M, Resch H, Mayer M, Hitzl W. Mid- to long-term outcome of instrumented anterior cervical fusion for subaxial injuries. Eur Spine J. 2009 May;18(5):630-53. 


Sunday, 18 August 2019

Neurological complications of lumbar epidural anesthesia and analgesia.

      Neurological complications of lumbar epidural anesthesia and analgesia.


                                     Dr KS Dhillon


Introduction


Epidural anesthesia and analgesia (EAA) are widely used in clinical practice for surgery and postoperative analgesia. Epidural anesthesia and analgesia reduces or eliminates perioperative physiological stress responses to surgery and this inturn decreases surgical complications and improve clinical outcomes[1-3].

Studies have shown a significant reduction in perioperative cardiac morbidity, pulmonary infections, deep vein thrombosis, pulmonary embolism, ileus, acute renal failure, blood loss and need for transfusion. The length of hospital stay and the 30 day mortality is also reduced with EAA [4]. EAA is also believed to preserve postoperative immune function by attenuating the stress response of surgery. Studies have shown significant reductions in the incidence of postoperative infections in patients treated with EAA [5,6].

EAA is generally regarded as safe and effective but EAA can be associated with serious complications. Though the complications are rare they can sometimes be devastating.

Neurological complications of lumbar epidural anesthesia and analgesia.


Studies show that the frequency of severe, permanent neurological complications related to epidural catheterisation is low at about  0.1–1/10,000 procedures [7-12]. Epidural anesthesia can be associated with radiculopathy, cauda equina syndrome and myelopathy leading to permanent neurological disability [13]. Compression of the spinal cord or nerve roots can occur from extradural abscesses or haematomas. Arterial and venous infarction of the spinal cord and nerve root trauma can occur during catheter placement. Chemically induced arachnoiditis by the drugs used for the epidural has also been implicated in causing permanent neurological disability [14-18].

Lumbar epidural injections in patients with pre-existing spinal stenosis can  precipitate severe and widespread lumbosacral polyradiculopathy [13,19].

Neurotoxicity from local anesthetics is a well known phenomenon and is related to the type and concentration of anesthetic and its systemic absorption. Intrathecal lignocaine at high doses has been associated with neurologic side effects [20,21].

Epidural catheters can inadvertently penetrate the dural space, cause damage to neurovascular structures and also can lead to infection. The incidence of accidental dural puncture during needle insertion is about 0.16–1.3% and the incidence of postdural headache in these patients is about 16–86% [22-25].

Nerve root irritation by the catheter and intrathecal injection of local anesthesia can produce transient neurologic symptoms (TNS) such as  sharp radicular back pain and paresthesias [26].

Risk factors for TNS include the use of lidocaine as the local anesthetic, lithotomy position, obesity, and performance of the procedure in the outpatient department [27].The TNS usually usually resolve once the catheter is removed. Epidural abscesses and meningitis following epidural and spinal anesthesia is rare [28].

Risk factors for meningitis include dural puncture, non sterile technique, prolonged indwelling catheter and septicemia [29,30]. Paraplegia, the most serious complication of epidural anesthesia can be caused by an epidural hematoma which forms during catheter placement or removal. The secondary cause of this complication is the concomitant pre-, intra-, or postoperative administration of drugs that affect blood coagulation (anticoagulants) [31].  Spinal abscesses and anterior spinal artery syndrome are also known to cause paraplegia. Epidural haematoma formation is a rare complication with an incidence of less than 1 in 150,000 [32].

Injury to the spinal vasculature during catheter placement has been described and the incidence is about 3–12%. Despite injury to spinal vasculature symptomatic epidural hematomas are rare [33,34]. Early recognition of symptomatic epidural haematomas and decompressive laminectomy within 8 hours have been shown to improve clinical outcomes [35].

Epidural abscess and meningitis


The reported incidence of epidural abscess after epidural catheterisation is about 1 : 1000 and for meningitis is about 1 : 50 000 [36].

There are several ways in which bacteria may enter the epidural space. One of the sources of infection is needle or catheter contamination and lack of barrier precautions, such as the use of chlorhexidine 0.5% in 70% alcohol for skin disinfection [37-39]. Contamination of the needle or catheter by oropharyngeal and nasal flora of the anesthetist has been proven by cultures obtained from the epidural abscess and from the anaesthetist [40,41].

Epidural solution can be a source of epidural infection despite the use of bacterial filter. There is some evidence to suggest that frequent syringe changes could be associated with a higher rate of epidural infection  [42-44]. The 500-ml bags of epidural infusion fluid has not been found to be  associated with epidural abscesses or meningitis [45].

Infection of the insertion site of the catheter with migration of the bacteria along the catheter tract is a common mechanism of epidural infections. A haematogenous source of epidural infection after epidural catheterisation is uncommon [46-48].

There are several predisposing factors for epidural infection. Patients who are immunocompromised are more likely to develop infection [49-51]. Difficulty in insertion of epidural catheter is also a known risk factor for infection. Difficulty in insertion is associated with the formation of asymptomatic epidural haematoma [49,52,53] or subcutaneous haematoma which can act as a nidus for infection [54]. Epidural analgesia of more then 3 days is associated with higher infection rates [51].

Staphylococcus is the most common organism cultured from epidural abscesses [49,50,51,55]. Methicillin resistant staphylococcus has also been cultured in some of these abscesses.

Patients with an epidural abscess usually presents with midline back pain and fever about 5 days after epidural insertion [49-51]. If untreated neurological deficit with paraplegia usually develops within a week [49]. The prognosis for recovery is poor once paraplegia develops [49,56].
Meningitis usually results from dural puncture and patients present with headache and fever, with some patients developing neck rigidity [50]. In some patients who developed meningitis there were no reports of dural puncture [45].

In patients suspected to have an epidural abscess, an MRI scan is the investigation of choice [58]. Sometimes back pain is ascribed to musculoskeletal pain and a delay in diagnosis can result. Therefore a high index of suspicion is necessary to prevent delays in diagnosis.

A lumbar puncture with csf microscopy is necessary for the diagnosis of meningitis [45].
Epidural abscesses are treated with a combination of early surgical decompression and prolonged antibiotic therapy [53]. Patients with minimal or no neurological deficit can be managed with antibiotics alone [55].

Epidural haematoma


Coagulopathies predispose patients to epidural haematomas following epidural catheter insertion [56]. Hence the timing of anticoagulant administration is important in reducing the risk of epidural haematomas [59,60]. The newer recommendations, recommend that low molecular weight heparin administration for prevention of deep vein thrombosis (DVT) be delayed for 24 h in case of a bloody tap [60]. Another risk factor for the development of epidural haematoma is difficulty in identifying the epidural space [61].

Difficulty in identification of the epidural space can often be encountered in patients who are obese. Other risk factors include advanced age, female gender and bony spinal pathology [50].
The usual clinical presentation of an epidural haematoma is radicular back pain with rapidly progressive neurological (motor and sensory) deficit and sphincter dysfunction [56]. The symptoms usually develop within 24 hours of either epidural insertion or removal, but sometimes the onset of symptoms may be delayed [50].

An MRI scan of the spine is the investigation of choice in patients suspected of having an epidural haematoma. Often the neurological deficit is attributed to the epidural infusion and the back pain to a musculoskeletal cause and this leads to a delay in diagnosis [62]. Early diagnosis is of paramount importance since a favourable outcome is dependent on early spinal decompression within 8 hours of the onset of symptoms [56]. Neurological outcome depends on the extent of the neurological deficit, the size of the haematoma and the time between haematoma formation and surgical decompression [56].

Leg strength monitoring is essential in assessment of spinal cord health
in patients receiving epidural analgesia [41]. The Bromage scale is commonly used to measure motor block [63].

Grade Criteria                                                                  Degree of block

I          Free movement of legs and feet                            Nil (0%)

II        Just able to flex knees with free movement
           of feet                                                                   Partial (33%)

III       Unable to flex knees, but with free movement     Almost complete
          of feet                                                                    (66%)

IV        Unable to move legs and feet                             Complete (100%)   


Table 1. Bromage scale

The perfect analgesic technique would provide complete pain relief with no motor block. Leg weakness during epidural analgesia must be treated with suspicion until proven to be reversible. [42].  Patients who have significant weakness of the leg should have epidural infusion stopped and if no motor recovery occurs within 4 hours, an urgent MRI scan should be performed [45] .

Direct penetration of the spinal cord during epidural catheterisation and subsequent injection of fluid into the substance of the cord, leading to localised hydromyelia has been proposed as one of the mechanisms for severe neurological complications resulting from epidural anaesthesia and analgesia [64]. Examination shows segmental levels of motor and sensory impairment which corresponds to the level of spinal cord injury. MRI shows tubular, clearly demarcated lesions which are hyperintense on T2 weighted images and hypointense on T1.

Air bubbles in the cord has been identified in patients who have become paraplegic after epidural anesthesia [65].

Local anesthetic drugs have been found to be potentially neurotoxic in experimental studies [66]. Polyethylene glycol found in methylprednisolone acetate is known to cause necrosis of neuronal tissue [67]. Injection of these neurotoxic drugs into the cord can cause damage to the cord.
Intravenous high dose methylprednisolone may be of value in these patients with cord damage.

Arachnoiditis and subarachnoid cyst


Arachnoiditis as a complication of epidural anesthesia has been reported.  Torres et al [68] reported 7 cases where patients developed arachnoiditis following epidural anesthesia. Subarachnoid cysts developed in all patients and in 5 cord cavitation developed. MRI was found to be useful in the detection of the arachnoiditis and the intramedullary cysts, as well as to monitor the extent of the lesion and progression of the lesions. In one case a tethered cord was present and in another there was spinal cord atrophy.

Possible etiology of these complications include scars from meningeal inflammation which induce ischemia leading to cavitation. CSF circulation blockade can also cause dilation of the central spinal canal which results in ischemia from compression followed by myelomalacia and cavitation.
Although progressive inflammation of the arachnoid due to trauma, infection, or hydrocortisone has been reported since the early 1970s,  coexistence of extensive syringomyelia (ES) and a giant anterior arachnoid spinal cyst (AASC) had not been reported until 2012. In 2012 Hirai et al [69] reported a case of adhesive arachnoiditis with extensive syringomyelia and a giant arachnoid cyst after spinal and epidural anesthesia. They had a  29 years old woman who presented with sudden anuresis 5 months after spinal/epidural anesthesia for cesarean section. She subsequently developed paraplegia with numbness below the chest. An MRI showed a giant AASC compressing the spinal cord at T1-T6 and there was an adhesive lesion at T7. Slight improvement in motor function occurred after
posterior laminectomy at T6-T7 and adhesiolysis at T7. Three years after the surgery motor function deteriorated further and posterior laminectomy at T5-T6 with insertion of a cyst-peritoneal shunt into the AASC was carried out.

Nogués et al [70] published a report where 3 women who had epidural anesthesia for gynecological surgery developed spinal arachnoiditis which led to subarachnoid cysts and cord cavitation. They found that MRI is useful for making a diagnosis and monitoring the extent and progress of the lesion.

Conclusion


Epidural anesthesia and analgesia (EAA) are extensively used in clinical practice for surgery and postoperative analgesia. Epidural anesthesia and analgesia reduces surgical complications and improve clinical outcomes.

Studies show a significant reduction in perioperative cardiac morbidity, pulmonary infections, deep vein thrombosis, pulmonary embolism, ileus, acute renal failure, blood loss and need for transfusion with EAA. The length of hospital stay and the 30 day mortality is also reduced with EAA. The incidence of postoperative infections is significantly reduced in patients treated with EAA. Though EAA is generally regarded as safe and effective, serious devastating neurological complications can occur following EAA.

Epidural abscess, meningitis, epidural haematomas, hydromyelia, cord cavitation, arachnoiditis and arachnoid spinal cysts are known complications of EAA which can produce serious and sometimes permanent neurological deficit including paraplegia. Prompt diagnosis and early aggressive treatment is essential for a good clinical outcome.


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Thursday, 8 August 2019

Anterior dislocation of the shoulder

                  Anterior dislocation of the shoulder     

                                          Dr KS Dhillon


Anatomy of the shoulder Joint

Glenohumeral joint 

The shoulder joint also known as the glenohumeral joint is formed by the articulation of the head of the humerus with the glenoid cavity of the scapula. The head of the humerus is much larger than the glenoid fossa (only 25–30% of the humeral head is covered by the glenoid surface). To reduce the disproportion in the size of the surfaces, the glenoid fossa is deepened by a fibrocartilage rim, called the glenoid labrum. The articular margins are covered with hyaline cartilage. The joint capsule extends from the anatomical neck of the humerus to the rim of the glenoid. The shoulder capsule is large, loose and redundant to allow greater mobility at the joint. The inner surface of the capsule is lined with synovial membrane.

Ligaments of the joint

At the anterior portion of the capsule is reinforced by the glenohumeral ligaments including the superior, medial and inferior glenohumeral ligaments. These ligaments provide anterior stability to the shoulder. Superior stability is provided by the coracohumeral ligament which extends from the base of the coracoid process to the greater tubercle of the humerus. A transverse humeral ligament which spans the distance between the two tubercles of the humerus holds the tendon of the long head of the biceps in the intertubercular groove. Another ligament, the coracoacromial ligament runs between the acromion and coracoid process of the scapula and it forms the coracoacromial arch.  This ligament lies superior to the shoulder joint and prevents superior displacement of the humeral head.

Muscles and tendons

The clinically important contractile structures of the shoulder joint are the supraspinatus, infraspinatus, subscapularis and, of less importance, the teres minor. They form the rotator cuff and these muscles arise from the scapula and attach to the tuberosities of the humerus. Superficially these muscles are separate but in the deeper region they merge with each other as well as with the capsule and the tendon of the long head of the biceps.

Movements of the shoulder joint

The glenohumeral joint is the most mobile joint in the human body. The movements at the shoulder joint include abduction, adduction, flexion, extension, internal and external rotation.

Abduction

The supraspinatus muscle and the deltoid muscle are responsible for this movement. The muscle plays an important role in initiation of abduction. When this tendon is completely torn the patient can no longer lift the arm actively and must make a swinging movement of the whole body in order
to start the movement. Once the arm has moved through 30° of abduction, the deltoid takes over to complete abduction. During full elevation of the limb to 180 degrees only 90 degrees takes place at the glenohumeral joint and the rest occurs at the scapulothoracic region. The deltoid is the prime mover and the supraspinatus is the accessory muscle.

Adduction

Adduction of the arm is performed by the teres minor and major, pectoralis major, latissimus dorsi and the long head of the triceps brachii. The pectoralis major and latissimus dorsi are the prime movers while the
teres major and long head of triceps brachii are the accessory muscles.

Flexion

Flexion of the arm is carried out by the pectoralis major, deltoid, coracobrachialis and the biceps brachii. The pectoralis major and deltoid are the prime movers while coracobrachialis and the biceps brachii are the accessory muscles.

Extension

Extension of the arm is performed by the deltoid, teres major, latissimus dorsi and the long head of the biceps brachii. The deltoid is the prime mover and the teres major, latissimus dorsi and the long head of biceps brachii are the accessory muscles.

Medial Rotation

Medial or internal rotation is carried out by the subscapularis, pectoralis major, deltoid, latissimus dorsi and teres major. The subscapularis is the prime mover and the pectoralis major, deltoid, latissimus dorsi and teres major are the accessory muscles.

Lateral Rotation

Lateral or external rotation is performed by the infraspinatus, teres major and the deltoid. The infraspinatus is the prime mover and teres major and deltoid are the accessory muscles.

Dislocation of the Shoulder Joint

Dislocations of the shoulder are described by the position of the humeral head in relation to the glenoid fossa after a dislocation has occurred. Anterior dislocations are the most common with prevalence rate of 95%. The prevalence rate for posterior is 4% and for inferior dislocations is 1%. The presence of the coraco-acromial arch superiorly prevents superior dislocation of the femoral head.

Anterior shoulder dislocation

Anterior shoulder dislocation has a bimodal age distribution. The first and the largest group are young adult men who sustained high-energy injuries to the shoulder. The second peak occurs in patients over the age of 60 years. This older group of patients are those who have a dislocation from a much lower level of violence. In the older group of patients early reduction and early mobilization to prevent joint stiffness is the management priority.

In the younger group of patients the risk of recurrent dislocation strongly correlates with the severity of initial injury the age of the patient. The risk is particularly high in the 16–30 year old group.
In anterior dislocation of the shoulder, violent external rotation in abduction  causes the humeral head to lever out of the glenoid socket. This is sometimes associated with avulsion of anterior bony and soft tissue structures. When a portion of the anterior labrum is detached from the glenoid and the anterior glenoid periosteum is torn, the lesion is referred to as a Bankart's lesion. Magnetic resonance arthrography shows that the prevalence of these lesions after first time anterior dislocation is about 23% [1]. When the posterior part of the humeral head exits the joint, the head collides with the anterior rim of the glenoid, creating a bony indentation at the back of the humeral head. This bony defect are known as a Hill Sachs lesions, the prevalence of which is as high as 71% after an anterior dislocation [1].

Clinical presentation

Following an anterior dislocation of the shoulder, the patient presents with severe pain and the arm is held in an abducted and externally rotated position. The normal counter of the shoulder is lost and a defect is palpable anterior, lateral and inferior to the acromion. The humeral head is usually palpable anteriorly in the region of the coracoid process.

Bony injury

Carrying out X rays of the shoulder including an AP and axillary view is mandatory for the diagnose an anterior dislocation of the shoulder as well as to exclude associated fractures. Hill Sachs lesions can be seen in 54% of the patients[2]. In older patients an associated greater tuberosity fracture is quite common.

Vascular injury

Stayner et al [3] reported two cases of axillary artery injury in 95 cases of shoulder dislocation which amounts to a prevalence rate of about 2%. This injury occurs more frequently in the elderly whose arteries are artherosclerotic.

In patients with axillary artery injury the pathognomonic triad consisting of anterior shoulder dislocation, absent or diminished distal pulses and protruding axillary haematoma is present [4]. Since the upper limb has an excellent collateral circulation, the radial pulse can be palpable and good capillary filling present despite the presence of major arterial injury [4]. The presence of reduced pulse pressure and coolness in the hand warrants an urgent angiography. Upper limb ischemia may be due to arterial spasm which does not need surgery. An angiogram can distinguish transient spasm from a tear which requires surgery.

Nerve injury

Nerve injuries are common after anterior dislocation of the shoulder. Visser et al [5] carried out a prospective clinical and electrophysiological examination in 77 patients with anterior dislocation of the shoulder. They found axonal loss in 48% of the patients. The axillary nerve was most frequently involved (42%). Function of the shoulder was significantly impaired in patients with axillary and suprascapular nerves injuries. They found that increasing age and presence of haematoma are unfavourable prognostic factors.

Te Slaa et al [6] reported a 21% incidence of nerve injuries in patients with primary glenohumeral dislocation. Atef et al [7] reported a much lower incidence of nerve injury in patients with anterior dislocation of the shoulder. They report isolated axillary nerve injury in 3.33% of the patients and combined nerve injuries in 12.5% of the patients. Most of the nerve injuries recover fully without intervention. There are some more severe injuries which do not recovery.
Brachial plexus injury can be associated with shoulder dislocation. These injuries are usually postganglionic, infraclavicular and in continuity. Hence the prognosis for recovery is excellent [8,9].

Rotator cuff tears

As with nerve injuries, the incidence of rotator cuff tears also vary widely. The incidence of rotator cuff tears in patients with anterior dislocation varies between 14%–65%.  The incidence of this complication increases with increasing age [10].

Treatment of anterior dislocation shoulder

There is no consensus in the literature on the best technique for reduction of a dislocated shoulder. Success of any technique would depend on the surgeon's familiarity and analgesia used [11].
The easiest way to reduce the dislocation is by manipulation under general anesthesia. However most of the dislocation are usually reduced in the emergency department.

Chitgopkar and Khan  [12] were able to reduce 10 out of 12 anterior dislocation of the shoulder by using the original Kocher's technique without any sedation or anesthesia. The original Kocher’s method is apparently gentle and  painless. The patient initiates the movements, the surgeon just guides the patient through the manoeuvre. In 2 patients the humeral head had to be guided proximally and laterally using an index finger in the axilla. The patients can  go home immediately after the procedure.

Uglow [13] carried out a prospective randomised trial involving 45 patients with an anterior dislocation of the shoulder who were randomised into one of two treatment groups and manipulation was performed using Kocher's  method. In one group entonox was used and in the other intravenous sedation was used. A successful reduction was achieved in 80.9% of Entonox group and in 100% of intravenous sedation group.

Kosnik et al [14] carried out a prospective, randomized, non blinded clinical trial involving 49 patients who had anterior dislocation of the shoulder to evaluate whether local intraarticular lidocaine injection is as effective as effective as intravenous analgesia/sedation in facilitating shoulder dislocation. They found that intravenous analgesia/sedation had a higher success rate (100%) as compared to intraarticular lidocaine injection (86%), the differences, however, were not statistically significant (P = 0.16).

Wakai et al [15] carried out a Cochrane systematic review to compare the clinical efficacy and safety of intra-articular lignocaine (IAL) and intravenous analgesia (with or without sedation) (IVAS) for reduction of acute anterior shoulder dislocation. They found no significant difference between IAL and IVAS with regard to the success rate of reduction, pain during reduction, post-reduction pain relief. IAL is apparently less expensive and associated with fewer adverse effects and the recovery time is also shorter with IAL.

Taylor et al [16] carried out a multicenter, randomized, clinical trial to compare propofol and midazolam/fentanyl for reduction of anterior shoulder dislocations using the modified Kocher's maneuver. They found propofol to be as effective as midazolam/fentanyl for reduction of anterior shoulder dislocation. They cautioned that the advantage of shorter wakening times with propofol should be weighed against possible adverse events such as respiratory depression and vomiting.
Gleeson et al [17] carried out a study to compare the use of supra-scapular nerve block with intra-articular lignocaine for reduction of anterior dislocation of the shoulder. They found that intra-articular lidocaine injection was easier to perform and also was more effective for pain relief.
Gleeson et al [18] in another study compared the effectiveness of Entonox to intra-articular local anaesthetic for shoulder reduction and found that Entonox was more effective then intraarticular local anesthetic for pain relief.

Management post reduction

Traditionally after the shoulder has been relocated it is immobilised in an arm sling in a position of internal rotation for about 3 weeks. Some have, however, challenged this tradition.

Hoveliu et al [19] carried out a study involving 245 patients with 247 primary anterior dislocations of the shoulder who were followed up for 10 years after the dislocation had been reduced. Post reduction patients were assigned to one of three treatment groups: immobilization with arm sling which was discontinued once the patient was comfortable, immobilization with arm tied to torso with a bandage for 3 to 4 weeks or immobilization for various duration. They found that the type and duration of the initial treatment had no effect on the shoulder dislocation recurrence rates.

Itoi et al [20] carried out a magnetic resonance imaging (MRI) study in patients who had had a dislocation of the shoulder to assess the degree of coaptation of the Bankart lesion with the arm in internal rotation and  external rotation. They found that the degree of separation of the torn labrum was significantly less in external rotation than in internal rotation. This would mean that immobilisation in a sling with the arm in an external rotation position would reduce the incidence of recurrent dislocation.

In 2003, Itoi et al [21] published the outcome of a prospective study involving 40 patients with anterior dislocation, where post reduction, 20 patients had conventional immobilization in internal rotation and the other 20 patients had their arm immobilized in external rotation. They found that the dislocation recurrence rate was 0% in the external rotation group and the recurrence rate was 30% in the internal rotation group at a mean follow up of 15.5 months. The difference in recurrence rate was even greater in patients less than 30 years of age, with a recurrence rate of 45% in the internal rotation group and 0% in the external rotation group.

Whelan et al [22] carried out a meta-analysis of randomized controlled trials to assess the effectiveness of internal rotation versus external rotation immobilization on the rate of recurrence after primary anterior dislocation of the shoulder. They found that immobilization in external rotation was not significantly more effective in reducing the recurrence rate.

Hanchard et al [23] carried out a Chochrane systematic review to assess the effects of conservative treatment after closed reduction of anterior dislocation of the shoulder. Their review showed that evidence from randomised controlled trials existed only for a single approach i.e immobilisation in external rotation versus immobilisation in internal rotation. The evidence available was insufficient to demonstrate whether immobilisation in external rotation was any better then immobilisation in internal rotation.

Paterson et al [24] carried out a systematic review and meta-analysis of the literature to determine the optimum duration and position of immobilization of the shoulder after anterior dislocation to prevent recurrent dislocation.

They found that there is no benefit of conventional sling immobilization for
longer than one week for the treatment of primary anterior shoulder dislocation in younger patients. They also found that an age of less than
thirty years at the time of injury was significantly predictive of recurrence.

Recurrent dislocation

The risk factors for recurrent dislocation of the shoulder are young age, participation in contact sporting activities, presence of Hill-Sachs or osseous Bankart lesion, ipsilateral rotator cuff or deltoid muscle insufficiency, and underlying ligamentous laxity.

Hoveliu et al [19] carried out a study involving 245 patients with 247 primary anterior dislocations of the shoulder who were followed up for 10 years after the dislocation had been reduced.They found a recurrence rate of 48%. The recurrence rate in the 12 to 22 year age group was 34%, 28% in the 23 to 29 year age group and 9% in the 30 to 40 year age group. Twenty three percent of the patients with recurrent dislocation needed surgery.

Twenty-two per cent of the shoulders that had at least two recurrences in the first two to five years stabilized spontaneously without operative intervention at ten years follow up.
Simonet and Cofield [25] carried out a study involving 116 patients with anterior dislocation of the shoulder. Their study showed a 33% recurrence rate. The incidence of recurrent dislocation was 66% in those less then 20 years old and 40% in those between 20 and 40 years of age. There were no recurrent dislocations in those who were older than 40 years of age. The recurrence rate was 82% in young athletes and 30% in non athletes of the same age.

Some patients do not experience repeat dislocation but may suffer from recurrent subluxation of the joint which limits their overall activity levels.

Treatment of recurrent anterior dislocation

There are numerous surgical procedures available for treatment of recurrent shoulder dislocation. These include open Bankart, arthroscopic Bankart, Latarjet, Bristow, and older techniques, such as Putti-Platt and Magnuson-Stack. Arthroscopic and open Bankart operations to repair the labral tear are usually performed on patients with glenoid labral tears. In patients with glenoid bone loss the Latarjet or Bristow procedure is usually carried out. In both the Latarjet and Bristow procedures the coracoid process is osteotomized and transferred with the conjoined tendons through a horizontal split in the subscapularis tendon and fixed to the scapular neck near the glenoid with a screw. The Putti-Platt and Magnuson-Stack procedures are nonanatomic historical procedures where shortening and tightening of the subscapularis tendon is carried out.

Glazebrook et al [26] carried out a systematic review of the literature to assess the quantity and quality of scientific evidence available for surgical procedures used in the treatment of anterior shoulder dislocations.

They allocated a grade of recommendation for each surgical procedure based on the quality of the studies. Grade A recommendations were based  on consistent level 1 studies, grade B recommendations on level 2 or 3  studies and grade C recommendations were based on level 4 or 5 evidence. Grade I articles have insufficient evidence to recommend a treatment.

They found evidence for grade A recommendation for four surgical procedures. The arthroscopic Bankart, open Bankart, and Latarjet procedures were given grade A for recommendation and the Putti-Platt procedure was given a grade A against recommendation.

Six surgical procedures were given a grade B recommendation. Arthroscopic remplissage, remplissage, and arthroscopic lavage were given grade B in favour of recommendation. Bristow, open capsular shift and thermal capsulorrhaphy were given a grade B against recommendation.

There were 11 grade C surgical procedures with 7 against and 4 in favour of recommendation. The 7 against recommendation procedures included Magnuson-Stack, Bankart and remplissage, Boytchev, Eden-Hybbinette, arthroscopic staple capsulorrhaphy, stapling operation, and Caspari technique. The 4 in favour of grade C recommendation included J graft, arthroscopic Latarjet, Latarjet-Patte, and iliac crest bone graft.

The Putti-Platt procedure is not recommended any more. It is an old procedure and the literature on the subject is outdated. Limitation of range of motion is common and the redislocation rates are very high. The most extensively studied procedure is the Bankart’s procedure. Most published studies report superior outcome with open Bankart as compared to arthroscopic Bankart, with a lower recurrence rate and no significant difference in complication rate [27,28]. There are also studies which suggest that the arthroscopic Bankart and open Bankart show comparable postoperative results in terms of stability, range of motion, and complications [29,30]. There are other level 1 studies which suggest that both surgical procedures are adequate but arthroscopic Bankart offers better postoperative results with greater stability, fewer complications, and better range of motion [31]. The Latarjet procedure has been reported to give promising results with low recurrence rates, high graft union rates, satisfactory clinical outcome scores, and few complications [32-34].

Historically, open repair remains the gold standard treatment against which other treatment options are compared. The open repair is associated with a 95% reduction in re-dislocation[2].

Long-term prognosis

Hovelius et al [2] reported an 8.7% incidence of moderate to severe osteoarthritis in patients who had their first dislocation when they were below the age of 40 years.

Ogawa et al [35] reported a higher incidence of osteoarthritis in patients with traumatic anterior shoulder instability who were due for surgery. Plain X-rays showed osteoarthritis in 11.3% of cases whereas CT scans showed osteoarthritis in 31.2% of the cases.
It would appear that osteoarthritis is not an uncommon complication of  anterior dislocation of the shoulder.

Conclusion

Anterior dislocation of the shoulder is the most common dislocation in the human body. There is a bimodal age distribution in patients with anterior dislocation. The first and the largest group are young adult men who sustained high-energy injuries to the shoulder. The second peak occurs in patients over the age of 60 where the level of violence is low. In the younger age group the incidence of recurrent dislocation can be very high. Anterior dislocation of the shoulder can be associated with rotator cuff tears, vascular injury, nerve injury and bony injury.

There is no consensus in the literature on the best technique for reduction of a dislocated shoulder. Several techniques have been described and there is no one technique which is more superior to another. There is also no consensus in the literature as to the method and duration of shoulder  immobilization after the dislocation has been reduced.

The incidence of recurrent dislocation varies between 9% to 82%. It is the highest (82%) in young athletes. The incidence of recurrent dislocation reduces as we age.

There are a large number of procedures which can be used to treat recurrent dislocation. The most commonly used techniques include Bankart’s repair and the Latarjet procedure. Not all patients with recurrent dislocation would require surgery. Some stabilize spontaneously with time.

Osteoarthritis is not an uncommon long term complication of shoulder dislocation.

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