Biomechanical Evaluation With a Novel Cadaveric Model Using Supination and Pronation Testing of a Lisfranc Ligament Injury

Biomechanical Cadaveric Evaluation of the Role of Medial Column Instability in Hallux Valgus Deformity

BACKGROUND

Medial column instability is a frequent finding in patients with flatfeet and hallux valgus, within others. The etiology of hallux valgus is multifactorial, and medial ray axial rotation has been mentioned as having an individual role. Our objective was to design a novel cadaveric foot model where we could re-create through progressive medial column ligament damage some components of a hallux valgus deformity.

METHODS

Ten fresh-frozen lower leg specimens were used, and fluorescent markers were attached in a multisegment foot model. Constant axial load and cyclic tibial rotation (to simulate foot pronation) were applied, including pull on the flexor hallucis longus tendon (FHL). We first damaged the intercuneiform (C1-C2) ligaments, second the naviculocuneiform (NC) ligaments, and third the first tarsometatarsal ligaments, leaving the plantar ligaments unharmed. Bony axial and coronal alignment was measured after each ligament damage. Statistical analysis was performed.

RESULTS

A significant increase in pronation of multiple segments was observed after sectioning the NC ligaments. Damaging the tarsometatarsal ligament generated small supination and varus changes mainly in the medial ray. No significant change was observed in axial or frontal plane alignment after damaging the C1-C2 ligaments. The FHL pull exerted a small valgus change in segments of the first ray.

DISCUSSION

In this biomechanical cadaveric model, the naviculocuneiform joint was the most important one responsible for pronation of the medial column. Bone pronation occurs along the whole medial column, not isolated to a certain joint. Flexor hallucis longus pull appears to play some role in frontal plane alignment, but not in bone rotation. This model will be of great help to further study medial column instability as one of the factors influencing medial column pronation and its relevance in pathologies like hallux valgus.

CLINICAL RELEVANCE

This cadaveric model suggests a possible influence of medial column instability in first metatarsal pronation. With a thorough understanding of a condition's origin, better treatment strategies can be developed.

Case Study: The Conservative Management of a Complex Mid Foot Injury in an Elite Professional Footballer

Lisfranc injuries, often accompanied with tarsometatarsal joint (TMTJ) disruption, are not well documented in football despite becoming increasingly more prevalent within other athletic populations. Currently there is a paucity of evidence documenting prognosis, rehabilitation strategy and outcome. The presented case summarizes the conservative rehabilitation and return to play of a 26-year-old elite professional footballer who presented with a Lisfranc injury alongside a 3^rd TMTJ coalition stress response. Injury was sustained when landing awkwardly from a jump causing the midfoot to be forced into a hyper-plantarflexed position. Palpation identified tenderness over the 2^nd and 3^rd MT, with a positive piano key test. Magnetic resonance imaging (MRI), computed tomography (CT), stork view x-ray and review from a leading foot and ankle specialist confirmed diagnosis, post-contradictory MRI results. Presented is a summary of the assessment process, conservative management of the injury and the resultant rehabilitation process followed, which led to the successful return to play of the athlete.

Sports-Related Lisfranc Injuries and Recognition of Lisfranc Variants: Surgical Strategies for Stabilization

Much has changed since Lisfranc described lesions at the tarsometatarsal (TMT) joint in 1815. What was considered an osseous high-energy condition nowadays is understood as myriad possible presentations, occurring in minor and inconspicuous traumas. Advancements in diagnostics of Lisfranc injury allow recognizing many variants of this trauma presentation, most of them with a focus on ligaments. This perception shifted trends in surgical planning, especially for implants and fixation techniques. These revolutions established a new and evolving universe around TMT lesions, different from what was known only a few years ago and still not enough to completely settle the disease scenario.