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support on the dorsal aspect of the Lisfranc joint (6,12,13).

A transverse line through the tarso- metatarsal joints is not straight but high- lights a recess formed by the second metatarsal, which lies within a mortise cre- ated by the three surrounding cuneiform bones (1). The osseous architecture of the joint, with its “keystone” wedging of the second metatarsal into the cuneiform, con- fers stability to the joint in the absence of ligamentous connections between the first and second metatarsal heads (1). The joints are bound by thick plantar ligaments arranged in an interlocking pattern between the tarsal and second to fifth metatarsals, and are reinforced by attach- ments from the tibialis posterior tendon (11).

Due to this anatomical configuration, the second metatarsal is prone to dorsal dislo- cation when an axial load is applied, when the foot is positioned in extreme plantar flexion.

Clinical presentation Midfoot swelling and the inability of the patient to weightbear on the affected foot, either immediately after the injury or when examined at a later date (4). Palpation with pain along the tarso-metatarsal joints indicates a midfoot sprain (7). In addition, stress should be applied to the tarso- metatarsal joints with passive pronatory and supinatory movements (5). Pain can localise to the medial or lateral aspect of the foot in the tarso-metatarsal region with digital palpation, or it can be pro- duced by abduction and pronation of the forefoot while the hindfoot is fixed; which may be the only movement which repro- duces discomfort in subtle injuries (7).

X-ray analysis should include weight-bear- ing antero-posterior, lateral, and oblique radiographs of the foot as non-weightbear- ing views of the foot can be normal (4,6). In addition, even if the first set of x-rays are normal, as the swelling decreases with time, this may allow the bones to move from their normal position, especially if the stabilising ligaments have been torn. For this reason, it is often necessary to take x-rays during the healing process and evaluate for the possibility of delayed development of instability (10). On x-rays, tarso-metatarsal dislocation is indicated by:

(i) loss of the in-line arrangement of the lateral margin of the base of the first metatarsal with the lateral edge of the medial cuneiform.

(ii) Loss of the in-line arrangement of the medial boundary of the base of the second metatarsal with the medial boundary of the middle cuneiform (14).

The lateral foot x-ray may indicate a “step- off”, suggesting that the dorsal surface of the proximal second metatarsal is higher than the dorsal surface of the middle cuneiform (15).

Differential diagnosis and associated longitudinal stress injuries ● Cuboid fracture ● Navicular compression fracture ● Ruptured tibialis posterior tendon ● Compartment syndrome

Treatment Early diagnosis of a Lisfranc joint injury is imperative for proper management and the prevention of a poor functional outcome (6). Even when the diagnosis is established, the optimum treatment approach and prog- nosis are subject to controversy (5).

If clinical evaluation indicates a mild sprain (pain at the joint, with minimal swelling and no instability) or moderate sprain (increased pain and swelling at the joint), treatment by immobilisation in a short-leg walking cast (13) or removable short-leg orthotic or non-weightbearing cast (7) is advocated for four to six weeks, or until symptoms have resolved.

Most investigators though (3,6,13,14) have concluded that with fracture dislocations of greater than 2mm there is little place for non-operative management as it is difficult to maintain anatomic reduction by closed reduction and immobilisation alone.

Immobilization in non-weight bearing is usually recommended for at least eight weeks (and possibly up to 12 weeks) with the timing of screw removal being debatable (16). Suggestions range from six weeks to six months from the time of surgery (6,7,10) and some authors (17) recommend the patient continues to wear a protective shoe, with a well moulded orthotic for three months after cast removal.

Conclusion Injuries to the tarso-metatarsal joint are

uncommon, but it is important to be aware of these injuries when assessing patients with acute foot trauma.

Ian Horsley MCSP, SRP is a chartered phys- iotherapist working in private practice in Wakefield. He lectures at the University of Salford within the Directorate of Sport and is currently completing an MSc in sports physiotherapy. Ian is currently physiothera- pist to England ‘A’ rugby union.

References 1. Englanoff G, Anglin D, Hutson HR. Lisfranc fracture disloaction : a frequently missed diag- nosis in the emergency department. Annals of Emergency Medicine 1995;26:229-33 2. Vuori J, Aro HT. Lisfranc joint injuries : trau- ma mechanisms and associated injuries. Journal of Trauma 1993;35(1):40-45 3. Hesp WL et al. Lisfranc dislocation: fractures and dislocations through the tarso-metatarsal joints. Injury 1984;15: 261-266 4. Burroughs KE, Reimer CD, Fields KB. (1998): Lisfranc injuries of the foot: a commonly missed diagnosis. Am.Fam.Physicians 1998;58:118-24 5. Harwood MI, Raikin SM. A Lisfranc fracture - Dislocation in a football player. Journal of American Board of Family Practice 2003;16(1):69-72 6. Mantas JP et al.Lisfranc injuries in the ath- lete. Clinical Sports Medicine 1994;13: 719- 730 7. Trevino SG, Kordos S. Controversies in tarso- metatarsal injuries. Orthop.Clin.North Am. 1995;26:229-238 8. Perron AD, Brady WJ, Keats TE. Orthopaedic pit-falls in the E.D. Lisfranc fracture dislocation. Am.J.Emerg.Med. 2001;19:71-5 9. Goossens M, De Stoop N. Lisfranc’s fracture- dislocations: Treatment. A review of 20 cases. Clin.Orthop.& Rel.Research 1983;176:154-162 10. Myerson M. The diagnosis and treatment of injuries to the Lisfranc joint complex. Orthop. Clin. North Am. 1989;20:655-664 11. Shapiro MS, Wascher DC, Finerman GA. Rupture of Lisfranc ligament in athletes. Clinic.Sports Med, 1994;22(S):687-691 12. Wiley JJ. The mechanism of tarso-metatarsal joint injuries. J. Bone Joint Surg (Br) 1971;53:474-82 13. Heckman JD. Fractures and dislocations of the foot. In Rockwood, C.A., Green, D.P., Bucholz RD, eds. Rockwood and Green’s frac- tures in adults. Vol 2, 3rd ed. Lippincott, Williams and Wilkins. pp2140-2151. Philadelphia 1991 14. Buzzard BM et al. Surgical management of the acute tarsometatarsal fracture dislocation in the adult. Clin. Orthop.1998;353: 125-133 15. Markowitz HD, Chase M et al. Isolated Injury of the record tarsometatarsal joint. A case report. Clin. Orthop 1989;248: 210-212 16. Myerson MS et al. Fracture dislocations of the tarso-metatarsal joints: end results correlat- ed with pathology and treatment. Foot and Ankle 1986;6:225-242 17. Arntz CT, Hansen ST.Jr. Dislocations and frac- ture dislocations of the tarso-metatarsal joints. Orthop. Ain North Am. 1987;18:105-114

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