The Lisfranc joint complex connects the midfoot to the forefoot, with the Lisfranc ligament providing critical stability between the medial cuneiform and the second metatarsal base. A Lisfranc injury ranges from a sprain of this ligament to a complete dislocation of the midfoot joints, and is notoriously underdiagnosed on initial evaluation — making MRI essential when clinical suspicion exists.
Lisfranc injuries are frequently mistaken for simple ankle sprains at the time of injury, particularly low-energy variants in athletes. Midfoot pain that persists beyond what is expected after a twisting injury should raise suspicion for a Lisfranc injury. Associated injuries to the plantar plate and forefoot structures may also be present in higher-energy mechanisms.
Causes
Low-energy injuries
In athletes, Lisfranc injuries often occur from twisting forces on a plantarflexed (pointed-down) foot — such as a football player having their heel stepped on, a horseback rider catching a foot in a stirrup during a fall, or simply misstepping off a curb. These subtle mechanisms frequently result in ligament sprains or partial tears that are missed on initial X-rays, making MRI critical for accurate diagnosis.
High-energy injuries
Severe Lisfranc fracture-dislocations result from high-energy trauma such as motor vehicle accidents, falls from height, or crush injuries. These typically produce obvious deformity, multiple fractures, and significant swelling and are less likely to be missed on initial imaging.
Symptoms
Patients describe midfoot pain and swelling, often with bruising on the bottom of the foot — plantar ecchymosis is highly suggestive of a Lisfranc injury and should prompt further investigation even when X-rays appear normal. Inability to bear weight, pain with toe-off during walking, and a sense of midfoot instability are characteristic findings. Subtle low-energy injuries may present only as persistent midfoot pain following a relatively minor twisting event, which is why a high index of suspicion and MRI evaluation is essential in this setting.
Diagnosis
Clinical examination reveals tenderness directly over the Lisfranc joint, midfoot swelling, and pain with passive pronation and abduction stress of the forefoot. Weight-bearing X-rays are the essential first study — non-weight-bearing films frequently appear normal even in unstable injuries. Widening between the first and second metatarsal bases or a small avulsion fracture at the second metatarsal base (the "fleck sign") on weight-bearing films indicate significant ligament disruption.
MRI is the definitive imaging modality for evaluating the Lisfranc ligament and is indispensable when weight-bearing X-rays are normal but clinical suspicion remains. MRI directly visualizes the Lisfranc ligament, identifying partial tears, complete ruptures, and the important distinction between a stable sprain and an unstable injury requiring surgery. It also identifies bone marrow edema at the medial cuneiform and second metatarsal base — a sensitive marker of significant ligament stress — and detects associated injuries to adjacent midfoot ligaments and joints that influence surgical planning.
Injury Grades
Lisfranc injuries are graded based on the degree of joint disruption:
- Grade 1 (Stable sprain): Lisfranc ligament sprain without joint widening or instability on weight-bearing imaging. Conservative management appropriate.
- Grade 2 (Partial tear): Partial ligament disruption with mild joint diastasis (1–2 mm) but no frank dislocation. Stability assessment with weight-bearing imaging and MRI guides management.
- Grade 3 (Complete disruption): Complete ligament rupture with frank diastasis greater than 2 mm, joint instability, and often associated fractures. Surgical treatment required.
Treatments
Treatment depends on injury severity and stability. Prompt accurate diagnosis is the single most important factor in long-term outcome — missed or delayed Lisfranc injuries treated late have significantly worse results.
Grade 1 (stable) injuries: Non-weight-bearing immobilization in a short leg cast or walking boot for 4–6 weeks, followed by gradual progressive weight-bearing and physical therapy. Repeat weight-bearing X-rays at follow-up are essential to confirm maintained stability, as some injuries that appear stable initially can displace with loading.
Grade 2 and 3 (unstable) injuries: Surgical stabilization is required to restore joint alignment and prevent progressive midfoot collapse. Options include open reduction and internal fixation (ORIF) with screws or plates to anatomically reduce and hold the joints, or primary arthrodesis (fusion) of the Lisfranc joint complex. Primary fusion is increasingly favored for ligamentous injuries without significant bony involvement, as it avoids the need for hardware removal and has shown comparable or superior outcomes to ORIF in several studies.
Long-term considerations: Post-traumatic midfoot arthritis is a recognized sequela of Lisfranc injuries even with optimal treatment, particularly in higher-grade injuries. Patients with persistent midfoot pain following initial treatment may eventually require midfoot fusion. Early and accurate diagnosis — particularly with MRI for subtle injuries — substantially improves outcomes by ensuring appropriate treatment is initiated before secondary deformity or arthritis develops.
Get an MRI to Confirm Your Diagnosis
Before surgical planning or starting treatment, a clear MRI diagnosis ensures the right path forward. First Look MRI offers self-pay Foot and Ankle MRI scans — no doctor's order or insurance required — at our locations in Georgia, Texas, and Colorado.