[Triple arthrodesis in treatment of degenerative hindfoot deformities: clinical, radiological and pedobarographic results]. / Die Triple-Arthrodese in der Therapie degenerativer Rückfussfehlstellungen: Klinische, radiologische und pedobarografische Resultate.

INTRODUCTION: Triple arthrodesis is performed to reconstruct a painless plantigrad foot in cases of fixed and painful hindfoot deformity. Mid-term results of our patients after triple arthrodesis concerning clinical and functional as well as radiological outcome were assessed in this examination. PATIENTS AND METHOD: In the retrospective study, 24 feet in 20 patients with triple arthrodesis after degenerative hindfoot malposition were examined. Sampling was done consecutively. The average age of the patients was 62.8 years (40-79), mean follow-up-period was 21.5 months. The patients were examined using the AOFAS score, assessment of subjective satisfaction and X-rays. In addition, the position of the foot was analysed using dynamic pedobarography and gait analysis. RESULTS: In the examined population, the mean AOFAS score was 74 (+/- 12.41) out of 94 points, the improvement averaged 51 (+/- 14.72) points. 75 % of the patients had no or only slight pain, 8 % reported limitations in everyday life. Mobility of the ankle was more than 30 degrees for 9 patients (38 %) and between 15 and 30 degrees for 13 patients (54 %). 23 patients out of 24 were satisfied with the result of the surgery. In most cases, dynamic pedobarography showed a rather physiological pattern of plantar pressure distribution with increased pressure remaining in the midfoot area. Valgus position of the hindfoot was 2.8 degrees (+/- 2.9 degrees), gait analysis showed very good results in 11 cases and good results in 13 cases. Among the examined patients, two cases of wound healing disorders appeared, and one non-union of the talonavicular joint which had to be reoperated. In two cases, clinically relevant degenerative changes of the ankle were diagnosed. CONCLUSION: Triple arthrodesis using internal fixation followed by sufficient immobilisation is a good and reliable technique for the correction of fixed hindfoot deformities. A very high level of patient satisfaction and a good clinical outcome can be achieved. Plantar pressure distribution can be reconstructed to a satisfactory extent. Due to the relatively high rate of degenerative arthritis in adjacent joints, the decision upon performing a triple arthrodesis should be considered carefully. Clinical and radiological integrity of these joints are required.