Lisfranc Injury

                                     Dr. KS Dhillon

Introduction

A Lisfranc injury or dislocation describes a spectrum of injuries involving the tarsometatarsal joints of the foot. The Lisfranc joint is composed of the articulation between the cuneiform bones and the first, second, and third metatarsal bones. There can be complete tarsometatarsal displacement with associated fractures and ligamentous tears or partial sprains with no displacement. A Lisfranc injury can involve various parts of the foot. The Lisfranc ligament is an isolated ligament that connects the medial cuneiform to the second metatarsal.

Lisfranc joint injuries are uncommon. They are often misdiagnosed and mismanaged. It is important to recognize these injuries early and start treatment promptly. Failure to recognize and treat these injuries will lead to midfoot arthritis, chronic pain, and functional instability. Even when these injuries are recognized and treated promptly, there is still a high risk for chronic disability and complications [1].

Anatomy

The Lisfranc joint complex has a specialized bony and ligamentous structure that provides stability to the joint. The Lisfranc joint complex is made up of three cuneiform bones (C1 to C3) and the cuboid bone (Cu) proximally and the five metatarsal (M1 to M5) bases distally linked together by a ligamentous capsule structure.

The Lisfranc joint can be divided into three longitudinal columns:

• Medial, composed of C1 and M1

• Central (middle), composed of C2-C3 and M2-M3. The space between the base of the second metatarsal bone and the first cuneiform bone is filled with the ligament key of the Lisfranc joint. The space between the bases of the third and fourth metatarsal bone is filled with the intermetatarsal ligament

• Lateral, composed of Cu and M4-M5.

The bony stability is determined by the trapezoidal shape of the base of the M1-M2-M3, with their respective cuneiform bones forming a stable arch known as a “transverse arch or Roman arch” with the second tarsometatarsal (TMT) joint as the keystone.

The tarsometatarsal complex includes the TMT joints, the intermetatarsal ligaments, and the intercuneiform joints. The ligamentous structure of the Lisfranc joint can be divided schematically into:

• Dorsal ligament and plantar ligament. The first is the smallest and the weakest crossing each TMT joint. The second is twice as large as the first. This explains why the dislocation is often dorsal

• The interosseous ligament, commonly known as the “Lisfranc ligament”, is the biggest. It is 4.5 times larger than the dorsal ligament and twice as large as the plantar ligament

• Intermetatarsal ligaments joining the second to the fifth metatarsal. Between M1 and M2 there isn’t an intermetatarsal ligament.

Joint capsules, plantar muscles, fascia, and tendons of the peroneus longus, of the tibialis anterior, and of the tibialis posterior contribute to midfoot stability and support the arch of the foot. 

Etiology

This type of injury can be caused by direct or indirect mechanism. A direct mechanism of injury occurs when there is a crush injury to the joint region from an event such as a motor vehicle collision or industrial accident. An indirect injury is more common than a direct injury. Indirect injury is often associated with sports participation. This mechanism of injury involves a longitudinal force while the foot is plantar flexed with a medial or lateral rotational force. Another frequent presentation is stepping off a curb with the foot forcefully plantar flexed [2,3].

Epidemiology

Lisfranc injuries are uncommon. They account for 0.2% of all fractures. The prevalence is probably higher as these injuries frequently go undiagnosed. The reported incidence of Lisfranc injury is approximately 1 per 55,000 persons per year. This injury occurs in all ages but is more common in the third decade of life. It is more common in males. Lisfranc injuries occur more frequently in athletes and are increasingly diagnosed in this group [4].

Pathophysiology

A Lisfranc injury occurs as a result of trauma without underlying pathophysiology. People with diabetes and individuals with nerve damage in the foot are more susceptible to this injury. Decreased sensation of pain can lead to repetitive injury or wear and tear making the patient more susceptible to a Lisfranc injury. 

History and Physical Examination

The patient will usually complain of midfoot pain following an acute injury. The injury may be a direct or an indirect injury. The pain is worsened by forefoot weight bearing, and the patient has difficulty with push-off. The severity of the injury is often underestimated at the time of initial injury and the presentation may be delayed. Midfoot pain beyond five days, swelling, and difficulty with push-off activities would indicate a Lisfranc injury. 

Inspection of the affected foot will show significant swelling, ecchymosis, and although less common, obvious anatomic deformity. There is pain on palpation over the dorsal mid-foot, more specifically over the tarsometatarsal joints. There is pain with combined abduction and eversion of the forefoot. Pain can also be reproduced with passive pronation or supination of the tarsometatarsal joint. Open fracture-dislocations are a surgical emergency [1,5].

Evaluation

When a Lisfranc injury is suspected, anteroposterior, 30-degree oblique, and lateral weight-bearing radiographs are obtained. In purely ligamentous injuries, an axial force during the radiograph is needed to illustrate the injury better. Radiographic findings of a Lisfranc injury or dislocation can show malalignment of the lateral margin of the first metatarsal base with the lateral edge of the medial cuneiform, malalignment of the medial aspect of the second metatarsal base with the medial edge of the middle cuneiform, and/or small avulsion fragments from one of the metatarsals or cuneiform bones. The finding of avulsion fractures are referred to as a “fleck sign” and suggests a Lisfranc injury. Displacement of more than 2 mm between the first and second metatarsal bases is considered a positive radiographic finding and is suggestive of a Lisfranc injury. On oblique view radiographs, the medial aspect of the cuboid bone should line up with the medial aspect of the fourth metatarsal base. The dorsal cortex of the first metatarsal and medial cuneiform should be aligned on the lateral weight-bearing X-rays. 

When there is doubt about the diagnosis after X-rays are done, a CT scan would be useful. It can show small avulsion fractures that may be otherwise missed. A CT scan can also be helpful for surgical planning. MRI may be useful for evaluating a ligamentous injury [6,7,8,9,10].

Treatment 

Lisfranc injuries can be managed conservatively or operatively depending on the clinical presentation. Initial treatment includes reduction, splitting, and elevation of the foot. 

Conservative treatment is only reserved for anatomically stable and non-displaced injuries. In such cases, the foot is put in a cast or boot. Ambulation is non-weight bearing using crutches. X-rays are repeated after 2 weeks to look for any diastasis. After six weeks if there is no foot tenderness and X-rays are normal weight-bearing and rehabilitation can be started.

Patients with diastasis or displacement would require surgery. The patient has to be non-weight bearing after surgery for six to eight weeks. A walking boot or cast can be considered as clinical presentation indicates. This cast or boot is then usually worn for six weeks. Once the cast is removed a progressive functional rehabilitation program is started [11,12,13].

Conclusion

As many as 20% of Lisfranc injuries are missed on initial presentation. First and second-degree sprains have been classified as partial ligament tears. There is pain, swelling, and no instability, and the radiographs are normal. Instability with diastasis greater than 2 mm between the first and second metatarsals, as seen on anteroposterior radiographs, is consistent with a third-degree sprain. Post-traumatic arthrosis is a very common complication of Lisfranc joint injury in patients with higher injury mechanism and purely ligamentous dislocations [14][15].

The diagnosis of Lisfranc joint injury is not always easy. When a Lisfranc injury is suspected, anteroposterior, 30-degree oblique, and lateral weight-bearing radiographs are obtained. Boney injuries are usually obvious on X-rays. In purely ligamentous injuries, an axial force during the radiograph is needed to illustrate the injury better. If proper X-rays are not obtained, the patient's disorder remains undiagnosed leading to more morbidity.

Treatment can be conservative or surgical depending on the type and severity of the injury.

References

1. Kalia V, Fishman EK, Carrino JA, Fayad LM. Epidemiology, imaging, and treatment of Lisfranc fracture-dislocations revisited. Skeletal Radiol. 2012 Feb;41(2):129-36.

2. Murphy N, Olney D. Lisfranc joint injuries: trauma mechanisms and associated injuries. J Trauma. 1994 Mar;36(3):464-5. 

3. Desmond EA, Chou LB. Current concepts review: Lisfranc injuries. Foot Ankle Int. 2006 Aug;27(8):653-60.

4. Kaar S, Femino J, Morag Y. Lisfranc joint displacement following sequential ligament sectioning. J Bone Joint Surg Am. 2007 Oct;89(10):2225-32.

5. Weatherford BM, Anderson JG, Bohay DR. Management of Tarsometatarsal Joint Injuries. J Am Acad Orthop Surg. 2017 Jul;25(7):469-479.

6. Hardcastle PH, Reschauer R, Kutscha-Lissberg E, Schoffmann W. Injuries to the tarsometatarsal joint. Incidence, classification and treatment. J Bone Joint Surg Br. 1982;64(3):349-56.

7. Perron AD, Brady WJ, Keats TE. Orthopedic pitfalls in the ED: Lisfranc fracture-dislocation. Am J Emerg Med. 2001 Jan;19(1):71-5. 

8. Englanoff G, Anglin D, Hutson HR. Lisfranc fracture-dislocation: a frequently missed diagnosis in the emergency department. Ann Emerg Med. 1995 Aug;26(2):229-33. 

9. Brown DD, Gumbs RV. Lisfranc fracture-dislocations: report of two cases. J Natl Med Assoc. 1991 Apr;83(4):366-9. 

10. Llopis E, Carrascoso J, Iriarte I, Serrano Mde P, Cerezal L. Lisfranc Injury Imaging and Surgical Management. Semin Musculoskelet Radiol. 2016 Apr;20(2):139-53.

11. Markowitz HD, Chase M, Whitelaw GP. Isolated injury of the second tarsometatarsal joint. A case report. Clin Orthop Relat Res. 1989 Nov;(248):210-2. 

12. Lattermann C, Goldstein JL, Wukich DK, Lee S, Bach BR. Practical management of Lisfranc injuries in athletes. Clin J Sport Med. 2007 Jul;17(4):311-5.

13. Sanli I, Hermus J, Poeze M. Primary internal fixation and soft-tissue reconstruction in the treatment for an open Lisfranc fracture-dislocation. Musculoskelet Surg. 2012 Jun;96(1):59-62.