Triangular Fibrocartilage Complex (TFCC) Injuries

      Triangular Fibrocartilage Complex (TFCC) Injuries
                                 

                                         Dr KS Dhillon

Introduction

The triangular fibrocartilage complex (TFCC) is actually a complex structure which suspends the distal radius and ulnar carpus from the distal ulna and provides a gliding surface distal to forearm bones for three dimensional movements at the wrist. Wrist pain is a common condition which is often described as "Back Pain" of the wrist. Injuries to the TFCC are not uncommon and abnormalities of the TFCC are common even in asymptomatic individuals. There is no consensus in literature regarding the best way to treat injuries of the of TFCC, although most hand surgeons would like to believe that surgical treatment gives the best clinical outcome.

Anatomy of triangular fibrocartilage complex

The TFCC is the primary stabilizer (80% of the stability) of the distal radioulnar joint (DRUJ) and consists of the following structures:

• Dorsal and volar radioulnar ligaments
• Ulnocarpal ligaments; volar ulno-lunate, ulno-triquetral and ulno-capitate ligaments.
• Triangular fibrocartilage (TFC) disk
• Meniscal homolog
• Tendon sheath of the extensor carpi ulnaris

The triangular fibrocartilage (TFC) is a bowtie shaped disk that separates the DRUJ from the carpal joint and lies at the end of the ulna. The central portion is relatively avascular with poor healing power and its peripheral parts (10% to 40%) which merge with the radioulnar ligament are relatively vascular. The meniscal homolog lies between the ulnar styloid and the triquetrum and it joins with the extensor carpi ulnaris tendon sheath and joint capsule to form a ligamentous stabilizer. The meniscal homolog,TFC, extensor carpi ulnaris tendon sheath, and the ulnocarpal ligaments do not significantly contribute to overall DRUJ stability (1).The main stabilizers of the DRUJ are the volar and dorsal radioulnar ligaments which have both deep and superficial components and these ligaments arise from the medial border of the distal radius.

Classification for TFCC abnormalities

Palmer classification (2) is commonly used to classify TFCC abnormalities. Palmer divides TFCC abnormalities into two main classes with several subtypes.

Palmer Class 1 traumatic injury
A. Central perforation
B. Ulnar avulsion with or without distal ulnar fracture
C. Distal avulsion
D. Radial avulsion with or without sigmoid notch fracture

Palmer Class 2 degenerative injury
A - TFCC wear
B - TFCC wear with lunate and/or ulnar chondromalacia
C - TFCC perforation with lunate and/or ulnar chondromalacia
D - TFCC perforation with lunate and/or ulnar chondromalacia and lunotriquetral (LT) ligament perforation
E - TFCC perforation with lunate and/or ulnar chondromalacia, LT ligament perforation, and ulnocarpal arthritis

Class I Lesions (traumatic)

Class IA lesions are traumatic tears or perforations of the TFC proper. These usually are located 2-3 mm medial to the radial aspect of the TFC and are about 1 -2-mm in length. Sometimes there can be a flap of redundant cartilage along the palmar aspect of the TFC. These lesion occur in avascular portion of the TFC, they cannot heal.

Class lB lesions are traumatic avulsions of the TFC from its ulnar foveal attachment. These tears can be associated with fractures of the ulna styloid. These tears can lead to radioulnar instability because of their association with injury to the palmar and dorsal radioulnar ligaments.
Class IB lesions occur in vascular zone and can thus heal.

Class IC lesions are traumatic avulsions of the peripheral volar attachments of the TFCC, specifically the ulnocarpal ligaments. These lesions can lead to ulnocarpal instability.

Class ID lesions are traumatic avulsions of the radial attachment of the TFC in the region of the sigmoid notch and they may be accompanied by distal radial and sigmoid notch fractures. These lesion heal poorly because of poor vascularity.

Class II Lesions (Degenerative)

In Class IIA lesions there is degenerative wear or thinning of the articular disk without perforation. This wear results from  chronic axial forces, commonly seen with ulna variance.

In Class IIB lesions more degeneration is seen with TFC thinning,  chondromalacia of the lunate, triquetrum, or the distal ulna. Although the TFC wear is more advanced but there is no perforation of the TFC.

In Class IIC lesions there  is further degeneration with oval central perforation of the TFC.

In Class lID lesions, besides TFC perforation and chondromalacia there is lunotriquetral ligament perforation with lunotriquetral instability.

In Class lIE lesions, besides the large central TFC perforations, chondromalacia, lunotriquetral ligament disruption, there is ulnocarpal and sometimes distal radioulnar arthritis.

Diagnosis of TFCC injury

TFCC injuries present with ulna side wrist pain often associated with a click. Turning a door key is usually painful. Examination shows a positive "fovea" sign where there is tenderness in the space between the ulnar styloid and flexor carpi ulnaris tendon and between the volar surface of the ulnar head and the pisiform bone. The positive “fovea” sign apparently has a 95% sensitivity and 87% specificity for foveal disruptions of TFCC or ulnotriquetral ligament injuries.
Besides the fovea sign there are several other clinical test for the diagnosis of TFCC tears [3]. These include :

•  Screwdriver test – ulnar sided pain or click with passive maximum ulnar deviation and active forearm rotation against resistance or clench and ulnar deviate while passively rotating or grinding the wrist. 
• GRIT test – pain limited grip strength in supination versus pronation. The grip strength is measured in 3 forearm positions (neutral, full supination, and pronation). The supination and pronation values are calculated as a ratio relative to neutral grip. A ratio of more than 1 is equal to a high potential for ulnar impaction and for TFC tear.  
• Ulnocarpal stress test (TFC grind test) – ulnar sided wrist pain with rotation from supination to pronation while an axial load is applied, the forearm is in vertical position, and the wrist is in maximum ulnar deviation
• TFC shear test (pisiform boost test, ulno-menisco-triquetral dorsal glide test) – pain when pisiform is pushed dorsally by thumb while index and middle fingers translate ulnar head volarly
• Press test – ulnocarpal pain when seated patient lifts body weight off chair using affected wrist 
• Ulnocarpal meniscoid test (waiter’s test) – bringing wrist passively from extension to ulnar deviation and then flexing and applying axial load eliciting pain with supination

Prosser et al [4] studied the diagnostic value of provocative wrist tests and magnetic resonance imaging (MRI) in patients with suspected ligamentous injuries of wrist. They found that provocative wrist tests are only mildly useful for diagnosing wrist injuries and a MRI only slightly improves the diagnostic accuracy as compared to provocative test and is only mild to moderately useful in diagnosing wrist injuries.

Andersson  et al [5] in 2015 did a systematic review of the literature to study the efficacy of magnetic resonance imaging and clinical tests in diagnosis of wrist ligament  injuries. A minimum negative predictive value (NPV) of 95% was considered as clinically relevant cutoff value. A NPV is defined as the probability of an intact wrist ligament given a negative investigation. The NPV of MRI for TFCC tears was between 37% to 90% and the NPV of clinical tests was only 55%. They concluded that a negative result from MRI is unable to rule out the possibility of a clinically relevant injury to the TFCC and clinical provocation wrist tests are of limited diagnostic value.

Prevalence of TFCC abnormalities on MRI of the wrist

Iordache et al [6] in 2012 studied the prevalence of TFCC abnormalities on MRI scans of asymptomatic wrists. They carried out MRI scans of the wrist in 103 asymptomatic volunteers. There was abnormalities of the TFCC in 39 wrists (37.86%). There was a complete tear of the TFCC in 23 wrists (22.5%). MRI abnormalities were seen in all wrists of subjects older than 60 years. The incidence of MRI abnormalities increased with age.

The authors concluded that the ‘prevalence of incidental TFCC findings in MRI scans of asymptomatic subjects is high’. Hence the presence of abnormalities on MRI of the wrist may be of questionable clinical meaning especially in those above the age of 50 years.
Chan et al [7] in 2014 did a systematic review and pooled analysis to see if  the prevalence of TFCC abnormalities regardless of symptoms increases with age. They found that the prevalence TFCC abnormalities increased from 27% in patients younger than 30 years to 49% in patients 70 years and older. In asymptomatic individuals the TFCC abnormalities increased from 15% to 49% in the same age groups. For symptomatic patients the prevalence ranged from 39% to 70% in patients between 50 and 69 years of age.

The authors concluded that since these abnormalities are so common they may be incidental findings. There is a need to find a reliable method to determine if these finding are the cause to the patients symptoms and we also need evidence to show that treatment improves symptoms better than placebo.

Treatment of TFCC injuries

Conservative or nonsurgical treatment for acute class I and class II TFCC injuries include temporary splinting of the wrist and forearm for 4 to 6 weeks, use of oral nonsteroidal anti-inflammatory medication (NSAIDs) , corticosteroid injections, and physical therapy. Surgical strategies include debridement, acute repair, and subacute repair.

Failure of conservative treatment may make surgery necessary. There are many surgical options available, depending on the type of lesion, including arthroscopic or open repairs of the ligaments and the disc, arthroscopic debridement,ulnar shortening, partial resection of the ulnar head (Wafer) or salvage procedures such as Darrach’s and Sauve‐Kapandji procedure.

Saito et al [8] in 2017 did a systematic review of the literature to study the outcomes of arthroscopic débridement for triangular fibrocartilage complex tears. They found 1723 studies of which there 18 studies which met the authors criteria. In 6 studies there was an increase in wrist flexion extension after the surgery and in 10 studies there was an increase in grip strength. In 6 studies the Disabilities of the Arm, Shoulder, and Hand scores improved and in 7 studies there was an improvement in pain visual analogue scale scores. Eighty-seven percent of patients returned to their original work.
The authors concluded that simple débridement can be performed with suitable satisfactory outcomes and few complication, though some patients may need further surgical procedures.

The authors of this article came under fierce criticism from fellow colleagues [8]. Henry and Ring [8] suspected that the data going into the above review was flawed. Of the 1723 studies found in literature on this topic, how is it that only 18 articles (1%) pertained strictly to arthroscopic triangular fibrocartilage complex débridement? It is very unusual to have only 18 studies in literature when wrist arthroscopy has been around for about 30 years and arthroscopic debridement is one of the most common wrist procedure carried out by arthroscopy. Could there be other relevant data hidden among those other 1705 publications? Henry and Ring believe that there is positive reporting bias in above review. We should be aware of  natural bias toward reporting positive outcomes and against reporting negative outcomes when we interpret the outcome of the review.

The major weakness of the review is that all 18 studies are uncontrolled case series (level IV evidence). Placebo effect of surgery can color the perception of the surgeons and the patients alike. We must resist drawing conclusions from uncontrolled level IV evidence data. What we need is studies like the one's done by Moseley et al [10] and Kirkley et al [11] who showed the futility of doing arthroscopic joint debridement for osteoarthritis (OA) of the knee. These two studies which included sham surgery provide level I evidence that joint debridement for OA is of no benefit to the patient.

We must avoid mistaking association for causation since TFCC abnormalities are common and often asymptomatic and hence we should not misinterpret the impact of therapeutic interventions [9].
Until sham-controlled trials are conducted, the value of arthroscopic debridement of the TFCC will remain unproven and potentially of no value.

Long-term follow-up studies to assess the durability of TFCC repairs and to see if the short term results of repairs deteriorate over time are needed.  The natural history of TFCC tears have to be studied and studies documenting the long term outcome of conservative treatment are also needed.

Conclusion

The anatomy of the TFCC has been well studied and elucidated and so has been the function of the TFCC. The diagnostic value of provocative wrist tests remains suspect and is of relatively low in diagnosis of TFCC injuries. The value of MRI in diagnosis is slightly better. Abnormalities of the TFCC are common and the incidence increases with age. Such abnormalities are often present in individuals who are asymptomatic. Although several surgical options are available in patients where conservative treatment has failed, the value these surgical options are suspect, since only uncontrolled level IV evidence data is available to support the use of these surgical options. In the absence of good data to support surgical intervention, conservative treatment should remain as the gold standard as is the case with treatment of osteoarthritis of knee in patient who are not suitable for a knee replacement.

References

1. Judy H. Squires, Eric England, Kaushal Mehta and Robert D. Wissman. The Role of Imaging in Diagnosing Diseases of the Distal Radioulnar Joint, Triangular Fibrocartilage Complex, and Distal Ulna. American Journal of Roentgenology. 2014;203: 146-153.
2. Palmer AK. Triangular fibrocartilage complex lesions: a classification. J Hand Surg [Am] 1989; 14:594-605.
3. Atzei A, Luchetti R. Foveal TFCC tear classification and treatment. Hand Clin. 2011 Aug;27(3):263-72. doi: 10.1016/j.hcl.2011.05.014.
4. Prosser R, Harvey L, LaStayo RP, Hargreaves I, Scougall P, Herbert RD. Provocative wrist tests and MRI are of limited diagnostic value for suspected wrist ligament injuries: a cross-sectional study. Journal of Physiotherapy 2011; 57(4): 247 - 253.
5. Andersson JK, Andernord D, Karlsson J, Fridén J. Efficacy of Magnetic Resonance Imaging and Clinical Tests in Diagnostics of Wrist Ligament Injuries: A Systematic Review. Arthroscopy. 2015 Oct;31(10):2014-20.e2. doi: 10.1016/j.arthro.2015.04.090.
6. Iordache SD, Rowan R, Garvin GJ, Osman S, Grewal R, Faber KJ. Prevalence of triangular fibrocartilage complex abnormalities on MRI scans of asymptomatic wrists. J Hand Surg Am. 2012 Jan; 37(1):98-103.
7. Chan JJ, Teunis T, Ring D. Prevalence of triangular fibrocartilage complex abnormalities regardless of symptoms rise with age: systematic review and pooled analysis. Clin Orthop Relat Res. 2014 Dec;472(12):3987-94.
8. Saito T, Malay S, Chung KC. A Systematic Review of Outcomes after Arthroscopic Débridement for Triangular Fibrocartilage Complex Tear. Plast Reconstr Surg. 2017 Nov;140(5):697e-708e. 
9. Henry SL, Ring DC. Discussion: A Systematic Review of Outcomes after Arthroscopic Débridement for Triangular Fibrocartilage Complex Tear. Plast Reconstr Surg. 2017 Nov;140(5):709e-710e.
10. Moseley JB, O'Malley K, Petersen NJ, et al. A controlled trial of arthroscopic surgery for osteoarthritis of the knee. N Engl J Med 2002;347:81-88.
11. Kirkley A, Birmingham TB, Litchfield RB, Giffin JR, Willits KR, Wong CJ, Feagan BG, Donner A, Griffin SH, D'Ascanio LM, Pope JE, Fowler PJ. A randomized trial of arthroscopic surgery for osteoarthritis of the knee. N Engl J Med. 2008;359((11)):1097–107.