TIBIOTALAR ARTHRODESIS: FOUR-YEAR OUTCOME IN A SERIES OF 68 PATIENTS

Abstract

Purpose: Tibiotalar arthrodesis is a classical procedure for the treatment of painful deformation-destruction of the tibiotalar joint. The purpose of this retrospective study was to determine prognostic factors and tolerance to tibiotalar arthrodesis observed in 68 procedures performed with two different techniques (47 surgical fusions (Group 1), and 21 arthroscopic fusions (Group 2)).

Material and methods: Between 1985 and 1999, 68 patients, mean age 51 years (22–88) underwent 55 arthrodesis procedures (47 post-traumatic, 2 paralytic, 6 rheumatoid polyarthritis, 4 sequelae of septic arthritis). All patients had major functional impairment. The tibiotalar joint was stiff in all cases and mean motion was 20 ± 15°. The subtalar facet was nearly normal in 33 cases, altered in six and had already fused in nine. The mediotarsal facet was altered in 12 cases, six had already had a double arthrodesis, and was normal in 50. On the preoperative Méary view, there was a normal axis in 13 patients, valgus in 28 and varus in 24. According to the Duquennoy radiographic criteria, there was subtalar involvement in 32 cases and mediotarsal involvement in 19. Tibiotalar arthrodeses procedures were performed arthroscopically after 1993 for cases with little axial deformation. Open surgery was used for all other cases (43 Méary technique). A plaster cast was used in all cases. All patients were reviewed using the Duguennoy score and two radiographic views: lateral weight-bearing view for the sagittal plane position (tibiopedious angle) and the Méary view for the frontal plane.

Results: At a mean follow-up of four years, fusion rate was 82% (group 1 83%, group 2 81%). Mean delay to fusion was 3.2 ± 1 month irrespective of the causal disease or surgical technique. Functional outcome was very good in 28%, good in 34.5%, fair in 34.5% and poor in 3% and did not depend on the surgical technique. The subtalar was painful with zero motion in 18 cases (26.5%), generally associated with residual equine. The mediotarsal was stiff in 17 cases and very painful in four. In the frontal plane, 16 ankles were correctly axed, 27 were in valgus (mean 5.6°) and 20 in varus (mean 7.6°) with no difference between the two groups. In the sagittal plane, four ankles were in talus, nine in neutral position, and 49 had a residual equine, including 32 > 5°. In most cases, fair or poor outcome was related to subtalar pain. More than 50% of the patients with equine fusion greater than 5° had subtalar pain.

Conclusion: For the same deformity, arthroscopic arthrodesis can shorten hospital stay and improve the rate and degree of trophic disorders. Arthroscopic tibiotalar arthrodesis is an elegant technique that we use for centred ankles or for patients with risk factors, particularly skin conditions. The rate of fusion with the arthroscopic approach is not however better than with open surgery. Precise clinical and radiological assessment of the subtalar facet as well as the position of the fusion in the sagittal plane at 90° without equine deviation are important prognostic factors observed in this series.