SUMMARY Anterior Tibialis Tendon Ruptures are traumatic anterior ankle injuries that can present with foot drop and impaired gait. Diagnosis is made clinically with presence of a painless mass at the anteromedial aspect of the ankle associated with weakness of dorsiflexion. Treatment is generally direct surgical repair of the tendon to achieve optimal functional outcomes. Etiology Pathophysiology mechanism of injury result of either laceration of the tendon or closed rupture may also result from strong eccentric contraction in young individual Medical conditions & comorbidities diabetes inflammatory arthritis Epidemiology demographics attritional rupture more common in older patients strong eccentric contraction more common in younger patients body location at the level of the ankle joint with varying degrees of retraction of the proximal stump risk factors older age diabetes fluoroquinolone use local steroid injection inflammatory arthritis Anatomy Ankle dorsiflexion primary ankle dorsiflexor (80%) tibialis anterior secondary ankle dorsiflexors extensor hallucis longus extensor digitorum longus Presentation History acute patient reports a 'pop' followed by anterior ankle swelling chronic patient reports difficulty clearing foot during gait Symtpoms: acute pain chronic may be painless Physical exam acute injury pain swelling anterior to ankle weakness in dorsiflexion of the ankle delay in diagnosis is common because of intact ankle dorsiflexion that occurs as a result of secondary function of the extensor hallucis longus and extensor digitorum longus muscles chronic injury inspection and palpation swelling may be minimal painless mass at the anteromedial aspect of the ankle loss of the contour of the tibialis anterior tendon over the ankle (tendon not palpable during resisted dorsiflexion) weakness use of the extensor hallucis longus and extensor digitorum communis to dorsiflex the ankle gait steppage gait (hip flexed more than normal in swing phase to prevent toes from catching) foot slaps down after heel strike Imaging Radiographs three views of foot and ankle helpful to exclude any associated osseous injury CT not indicated MRI helpful to diagnose complete versus partial tear but not to determine if interposition graft is necessary Differential Lumbar radiculopathy (L4) can be differentiated from TA rupture by intact tendon palpable no ankle mass may have dermatomal sensory abnormality positive lumbar spine MRI Common peroneal nerve compression neuropathy EDL, EHL also affected sensory abormalities history of compression to common peroneal nerve Treatment Nonoperative ankle-foot orthosis indications low demand patient casting indications partial ruptures Operative direct repair indications acute injury (<6 week) injuries in an active, high demand patient should be attempted up to 3 months out outcomes surgical repair leads to improved AOFAS scores and improved levels of activity some residual weakness of dorsiflexion is expected reconstruction indications most often required in chronic (>6 week) old injuries Technique Direct repair approach open laceration: incorporate laceration closed rupture: longitudinal incision centered over palpable defect repair technique distal end usually accessible through laceration, proximal end may retract ~3cm place hemostat in wound under extensor retinaculum and pull tendon into wound primary end-to-end non-absorbable suture with Krackow, Bunnell or Kessler technique if less then 5 degrees of ankle dorsiflexion with the knee extended perform gastrocnemius recession prior to tensioning repair ends oversewn with small monofilament if frayed to create smoother gliding surface in cases of avulsion, suture anchors or bone tunnels may be used for reattachment Tendon reconstruction approach curvilinear incision over course of tibialis tendon, may need to be extensile depending needs of reconstruction EHL can be divided through separate small incision and tunneled proximally sliding tendon graft harvest one half width of tibialis anterior tendon proximally and turn down to span gap repair can be strengthened by securing tibialis anterior tendon to medial cuneiform or dorsal navicular distal to extensor retinaculum free tendon graft interposition of autograft (hamstring, plantaris) or allograft EHL tenodesis or EHL transfer distal EHL stump tenodesed to EHB proximal EHL stump used as tendon graft to repair tibialis anterior insertion proximal tibialis anterior placed under tension prior to suturing to proximal EHL stump Complications Failure of reconstruction/repair Weakness of dorsiflexion Adhesion formation Neuroma formation Prognosis Good with treatment