Posterior Bone Block Distraction Arthrodesis of the Subtalar Joint: A Review of 22 Cases

Twenty-two patients underwent a posterior bone block distraction arthrodesis of the subtalar joint between 1999 and 2006. The indication for surgery was loss of heel height, subtalar joint arthrosis, decreased talar declination with associated tibiotalar impingement, insufficient Achilles tendon function, malalignment of the rear foot, and pain with ambulation. There were 11 male and 11 female patients with a mean age of 46.7 years (range 20 to 71). The mean follow-up period was 27.3 months (range 12 to 63.9 months). Radiographic analysis revealed a mean increase in heel height of 6.09 mm (P= .0001), 5.83 degrees (P= .12) of lateral talocalcaneal angle, 5.5 degrees (P= .06) of talar declination, and 5.23 degrees (P= .07) of calcaneal inclination. The talo-first metatarsal angle increased an average of 4.5 degrees (P= .18). There was a 95.5% union rate. Postoperative complications included nonunion in 1 patient, subsidence of graft (collapse) in 1 patient, wound dehiscence in 3 patients, painful hardware in 7 patients, sural neuritis in 1 patient, superior cluneal nerve dysfunction in 1 patient and one mild varus malunion. Posterior bone block distraction arthrodesis can be successfully used to restore heel height, realign the foot, and decrease the morbidity associated with late complications of calcaneal fractures, as well as, nonunion and/or malunion following subtalar joint arthrodesis, Charcot neuroarthropathy, and avascular necrosis of the talus. LEVEL OF CLINICAL EVIDENCE: 4.