[Arthroscopic tibio-talar arthrodesis: limitations and indications in 20 patients].

PURPOSE OF THE STUDY: The purpose of this study was to present the clinical and radiological outcome in 20 patients who underwent arthroscopic tibiotalar arthrodesis.

MATERIAL AND METHODS: Between 1993 and 1999, twenty patients (twelve men and eight women) underwent arthroscopic tibiotalar arthrodesis and have been followed for a minimum of one year. Mean age at the time of the procedure was 55 years. The left side was treated in eleven patients and the right in nine. There were a variety of underlying conditions, but post-traumatic osetoarthritis predominated (ten patients); five patients had primary degenerative disease, three had "neurological" ankles, one had polyarthrtis and one necrosis of the talus. Three patients had previously undergone a double fusion and one other had had a subtalar arthrodesis. The preoperative Broquin score, which accounts for pain and walking distance, was 3.3 points on a scale of 8. The walking distance was less than 1000 meters for most of the patients. Radiographically, ten feet presented a frontal valgus deformity (mean 5.3 degrees); three had a varus deformity (mean 8 degrees) and seven were well-aligned. In the sagittal plane, there were ten cases of pes equin, including five greater than 10 degrees. The mean tibiopedal angle was 94+/-8 degrees.

RESULTS: Mean hospital stay was four days. There were four complications: two superficial infections that resolved and two cases of reflex dystrophy. First-intention fusion was achieved in 17 patients (85%) after a mean 3.7 months (range 3-10 months). Three patients presented a non-union, two undergoing successful open surgery and one preferring to decline surgery on a well tolerated non-fused ankle. At last follow-up, fifteen patients were satisfied or very satisfied and five were dissatisfied. Pain was minimal or absent in 67% of the cases. The Duquennoy score was good or very good in eleven patients, fair in eight, and poor in one. Radiographical data were available for nineteen patients: four had a correct alignment in the frontal plane, eight exhibited valgus (mean 4 degrees), and seven varus (mean 8 degrees). In the sagittal plane, fifteen feet exhibited pes equin (mean 7 degrees), three a neutral position and one pes talus (4 degrees). The mean tibiopedal angle at last follow-up was 95.4 degrees.

CONCLUSION: Although arthroscopic tibiotalar arthrodesis cannot improve the rate and delay to fusion in comparison with open surgery, it does reduce morbidity and the length of the hospital stay. We reserve the arthroscopic approach for ankles which are correctly or nearly correctly aligned without loss of bone stock, especially if there are local or general risk factors for open surgery.