These are radiographs as well as a clinical photograph of the right foot of a 68-year-old man who stumbled down some stairs, injuring his right foot.
- Describe these radiographs.
These are radiographs of the right foot. They show widening between the first and second metatarsals. There is a fracture at the base of the second metatarsal. This represents a Lisfranc injury.
- Describe the clinical photograph and what findings you would expect on examination.
The photograph shows the classical finding is of a large medial plantar ecchymosis. Often patients will be unable to weight bear, which is in contrast to a midfoot sprain. Tenderness may be present throughout the whole tarsometatarsal joint region and there may be obvious soft tissue swelling.
- What additional imaging may be useful where the diagnosis is unclear and how would you interpret this?
I would initially request imaging in the form of anteroposterior, lateral and 30-degree oblique internally rotated plain radiographs of the foot. I would request that these
Lisfranc Injury 
are weight bearing radiographs if this can be tolerated by the patient. The anteropos- terior radiograph may show obvious, as in this case, or subtle widening between the first and second metatarsals. A small chip of bone is often evident: ‘the fleck sign’. This represents an avulsion from the second metatarsal or the medial cuneiform. Normal alignment on the anteroposterior view is represented by examining the lat- eral borders of the first and second metatarsals, which should line up with the lateral borders of the medial and middle cuneiforms, respectively. The oblique internally rotated view should also show that the medial border of the fourth metatarsal lines up with the medial border of the cuboid.
On the lateral radiograph, no metatarsal bone should lie more dorsally than the respective tarsal bone.
I would also look for any evidence of fractures in or widening between the cuneiforms. Any abnormalities may all be accentuated on weight bearing radio- graphs. Computed tomography can be used to image fractures and exclude occult injuries while MR imaging may allow direct visualisation of the Lisfranc ligament itself.
- How would you manage this patient?
If there is significant soft tissue swelling, I would admit the patient for elevation and regular ice treatment.
This injury represents an unstable articular injury. In the absence of any obvious contraindication I would advise that this patient should be treated operatively.
In an appropriately consented and anaesthetised patient and with a proximal thigh tourniquet, I would make a clinical and radiographic assessment for any instability between the medial and middle cuneiforms. If this is apparent then I would reduce and hold this articulation with a pointed reduction clamp first and then a percutaneous Kirschner wire.
I would use a dual dorsal incision approach. The first incision is based between the first and second metatarsals to address the first and second tarsometatarsal (TMT) joints. This will be centred over the TMT joint area and will allow access to the plane between extensor hallucis longus and extensor hallucis brevis, the latter of which is superficial to the neurovascular bundle. The second incision, if required, is between the third and fourth metatarsals at the same level.
I would inspect and address the second tarsometatarsal joint first. I would reduce the joint and hold this temporarily using an AO reduction clamp before securing this reduction with a 3.5 millimetre cortical lag screw passed from the medial cunei- form (through a separate stab incision) into the base of the second metatarsal, recre- ating the Lisfranc ligament.
I would then examine the first tarsometatarsal joint for instability. If required, I would reduce and fix this using a 3.5 millimetre cortical lag screw from the first metatarsal into the medial cuneiform.
If required, I would then turn my attention to the third TMTJ, which will be accessed through the second incision. I would stabilise the third ray against the secure second ray by passing a 3.5 millimetre cortical lag screw from the base of the third metatarsal into the lateral cuneiform.
Fixation of the medial TMT joints will often lead to indirect reduction of the fourth and fifth TMT joints. I would examine the lateral two rays for instability using image intensification and, if required, stabilise these rays using 1.6 millimetre K-wires from the respective metatarsals into the cuboid.
I would reassess the foot for intercuneiform instability and, if required, pass a
4.5 millimetre cannulated screw over the K-wire holding the middle and medial cuneiforms.
Postoperatively, I would place the patient in a below knee backslab and would inspect the wounds at 2 weeks and obtain further radiographs. I would advise the patient to remain non-weight bearing on the operated side for 8 weeks.
- How might your treatment change in the case of a delayed presentation?
For presentations up to 6 weeks, I would still consider open reduction and fixa- tion. For older injuries, the results of this treatment are less satisfactory. I would offer a symptomatic patient arthrodesis of the medial three tarsometatarsal joints. This would use the same surgical approach as acute fixation but would necessitate removal of any remaining articular cartilage and stabilisation of the medial three tarsometatarsal joints using lag screws or plates. An extensive delay before presenta- tion may mean that to realign the joints before fusion, soft tissue releases are also required.
