[Treatment of serious subtalar joint osteoarthritis and stage II posterior tibial tendon dysfunction by subtalar arthrodesis].

OBJECTIVE: To assess the curative effect of the subtalar arthrodesis on the serious subtalar joint with the posterior tibial tendon dysfunction.

METHODS: From October 2000 to February 2006, 31 patients (18 males, 13 females; age 23-62 years, averaged 36.4 years) with serious subtalar joint osteoarthrisis and stage II posterior tibial tendon dysfunction were treated by the subtalar arthrodesis. The tibial tendon dysfunction involved 15 right and 16 left lower extremities, which were caused by retrograde osteoarthritis in 14 patients, sequel of an injury in 8 patients, infection in 7 patients, and anatomic structural abnormity in 2 patients. The treatment course averaged 9. 5 months (range, 6-30 months). Before the subtalar arthrodesis, the injured tendons were repaired, and then the bone grafting was performed in the tarsus sinus. All of the patients were assessed before and after operation according to the Hindfoot scores system (American Orthopedics Foot and Ankle Society, AOFAS).

RESULTS: Among the patients, 28 were followed up on an average of 23.6 months (range, 8-61 months). The AOFAS scores ranged from 45.30+/-1.08 before operation to 79.60+/-2.14 after operation. The pain indexes ranged from 15.40+/-2.23 before operation to 38.50+/-2.61 after operation. The functional indexes of the foot and ankle joint ranged from averaged 21.60+/-3.01 before operation to averaged 37.40+/-2.83 after operation. The statistical analysis of the t-test on all the above data showed that there was a significant difference between before operation and after operation (P<0.01). The angles between the longitudinal line of the talar and the calcaneal bone were 43.70+/-1.06 degrees before operation and 29.40+/-0.98 degrees after operation, and the deviation angles between the calcaneal line and the talus were 48.20+/- 0.85 degrees before operation and 39.40+/-1.02 degrees after operation. There was a significant difference between before operation and after operation (P<0.01).

CONCLUSION: The subtalar arthrodesis combined with the bone grafting in the tarsus sinus and the repair of the injured tendons can effectively correct the deformity of the deformity of the metapodium, relieve the pain, retain the adjacent joint motion ability, and this method can be recommended for the adult patient who suffers from serious subtalar osteoarthritis and stage II osterior tibial tendon dysfunction.