Page 133 - ASOP Orthopedic Casting Manual

3.3.5 Fracture Type(s) for Short Leg

Cast

Lisfranc Fractures
✓ Clinical Relevant Anatomy: The Lisfranc joint complex is a critical stabilizing

structure of the midfoot, consisting of the tarsometatarsal LTMT) joints, the
Lisfranc ligament (bet ween the medial cuneifor m and second metatarsal
base), and the suppor ting joint capsule. This structure maintains the medial
longitudinal arch and allows for force distribution during ambulation. The
Lisfranc ligament is relatively weak, making it susceptible to dislocation or
fracture with excessive midfoot stress LMoore et al., 2020M.
✓ Epidemiology / Etiology / Mechanism of Injur y: Lisfranc injuries are relatively

rare, occur ring in 1 out of 55,000 fractures annually, but they are often
missed, leading to chronic instabilit y if untreated LEiff et al., 2020M. These
injuries t ypically occur due to high-energy trauma (e.g., motor vehicle
collisions, falls from height, or crush injuries) but can also be seen in low-
energy t wisting injuries, especially in athletes (e.g., football, gymnastics,
horseback riding).
✓ Clinical Characteristics / Presentation: L1M Midfoot pain, swelling, and bruising,

par ticular ly along the plantar sur face; Inabilit y to bear weight due to pain; L2M
Pain with passive forefoot abduction or dorsiflexion LLisfranc stress test); L3M
"Fleck sign" on X-ray – a small avulsion fragment at the base of the second
metatarsal indicating ligamentous injur y.
✓ Fracture Diagnosis Process / Physical Examination: Tender ness along the

midfoot, especially at the TMT joint complex; Assess for instabilit y by
applying dorsal-plantar stress to the forefoot.
✓ Imaging Studies: L1M Weight-bearing X-rays LAP, lateral, oblique views) to

assess for TMT diastasis €2mm; L2M CT scan if subtle fractures or
dislocations are suspected; L3M MRI to evaluate for Lisfranc ligamentous
disruption.
✓ Differential Diagnosis / Associated Injuries: Metatarsal fractures (isolated vs.

Lisfranc instabilit y); Midfoot sprains (without ligamentous rupture); Navicular
or cuneifor m fractures.
✓ Treatment / Management Considerations: L1M Stable Lisfranc injuries (without

diastasis): Managed with SLC for 6^8 weeks with non-weight-bearing for 6
weeks; L2M Unstable injuries L€2 mm diastasis): Require surgical fixation with
screws or plates to prevent chronic midfoot instabilit y and ar thritis; L3M Post-
immobilization rehabilitation: Progressive weight-bearing and midfoot
strengthening exercises for 3^6 months post-injur y LBucholz et al., 2021M.