Z-Plasty of the Flexor Hallucis Longus Tendon at Tarsal Tunnel for Checkrein Deformity

Purposes To review the outcome of Z-plasty of the flexor hallucis longus (FHL) tendon at the tarsal tunnel for checkrein deformity in 8 patients.Methods Records of 6 males and 2 females aged 14 to 67 (mean, 39.5) years who underwent Z-plasty (lengthening) of the FHL tendon at the tarsal tunnel for checkrein deformity in the first and second toes by a single surgeon were reviewed. All patients had undergone 3 months of conservative treatment. The mean time from injury to surgical treatment was 8.4 (range, 5–12) months. All patients had associated injuries including distal tibiofibular fracture (n=6), distal fibular fracture (n=1), and crush injury around the ankle (n=1); they were treated with intramedullary nailing (n=6), long leg splinting (n=1), and short leg splinting (n=1).Results After a mean follow-up of 3.4 (range, 1–7) years, the FHL tendon was lengthened by a mean of 1.7 (range, 1.6–1.8) cm, and the mean American Orthopedic Foot and Ankle Society hallux score increased from 59 (range, 52–67) to 89 (range, 80–90). No patient had recurrence, nerve injury, or tarsal tunnel syndrome, although one patient had sensory disturbance of the posterior tibial nerve in the forefoot, which resolved spontaneously at week 2.Conclusion Z-plasty of the FHL tendon at the tarsal tunnel is a viable option for correction of checkrein deformity.