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Tarsal Coalition 755.67


synonyms: Calcaneonavicular coalition, talocalcaneal coalition, peroneal spastic flatfoot

Tarsal Coalition ICD-10

  • Q66.89  Other specified congenital deformities of feet

Tarsal Coalition ICD-9

  • 755.67 (Anomalies of foot, NEC) tarsal coalitions, talonavicular synostosis, coalition of calcaneous, calcaneonavicular bar, astrgaloscaphoid synostosis)

Tarsal Coalition Etiology / Epidemiology / Natural History

  • Congenital anomaly with the union of 2 or more tarsal bones causing decreased or absent motion.
  • can be a cartilaginous, fibrous, or bony union most often seen in the hindfoot and less commonly in the midfoot.
  • typically teenager with increasingly midfoot pain, insidious onset, activity related, and relieved by rest. Stiffness of foot, hx of ankle sprains.
  • Disorder of mesenchymal segmantation. May be inherited in an autosomal dominant pattern. (Leonard MA: JBJS 1974;56Br:520-526)
  • Occurs in @1% of US population
  • 50-60% bilateral
  • talocalcaneal, calcaneonavicular most common. Rare=talonavicular, calcaneocuboid, cubitonavicular, and naviculocuneiform joints.
  • leading cause of peroneal spastic flatfoot

Tarsal Coalition Anatomy

Tarsal Coalition Clinical Evaluation

  • history of repeated ankle sprains or vague, nonspecific symptoms in the hindfoot or midfoot following minor trauma.
  • c/o calf pain due to peroneal spasticity, flatfoot, limited subtalar motion,
  • Typically teenagers, age 10-12
  • restriction of hindfoot inversion and eversion, full ROM of ankle

Tarsal Coalition Xray / Diagnositc Tests

  • plain radiographs often normal, best evaluated with CT scan(Herzenberg, Foot Ankle 1986;6:273-288)
  • C-sign on lateral x-ray is highly sensitive and specific for TCC. C-sign = a C-shaped line formed by the medial outline of the dome of the talus and the posteroinferior outline of the sustentaculum tali. (Sakellariou A et al: Talocalcaneal coalition: Diagnosis with the C sign on lateral radiographs of the ankle. JBJS Br 2000;82:574-578)
  • Other x-ray findings include a talar beak, narrowing of the posterior subtalar joint space, failure to visualize the middle subtalar joint, and loss of height of the longitudinal arch.
  • CT: indicated before surgical treatment to ipsilateral coalitions, ie concommitant calcaneonavicular and subtalar coalitions.

Tarsal Coalition Classification / Treatment

  • conservative=heel cup with medial-wedge or longitudinal arch support.  Short leg walking cast with slight varus mold for 2-4weeks followed by UCBL orthosis.
  • Calcaneonavicular or talocalcaneal coalition=WBSLC for 2-4wks followed by UCBL orthosis. Consider resection of the coalition and interposition of autogenous fat graft, or extensor digitorum brevis muscle if non-op treatment fails (Gonzalez P, JBJS 1990;72A:71).
  • Consider primary triple arthrodesis in patients with degenerative changes in the subtalar or midfoot joints.

Tarsal Coalition Associated Injuries / Differential Diagnosis

  • Fibular hemimelia
  • Proximal focal femoral deficiency
  • Phocomelia
  • Hypoplastic femur
  • Symphalagism
  • Carpal Coalitions
  • Apert syndrome
  • Nievergelt-Pearlman syndrome

Tarsal Coalition Complications

Tarsal Coalition Follow-up Care

Tarsal Coalition Review References

  • Kulik SA Jr, Clanton TO: Tarsal coalition.  Foot Ankle Int 1996;17:286-296.
  • Vincent KA, JAAOS, 1998;6:274
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