SUPRAMALLEOLAR OSTEOTOMY IN ADULTS: NINE CASES

Abstract

Purpose of the study: Frequently described in pediatric orthopedics, supramalleolar osteotomies are theoretically logical in adults, but relatively little studied.

Material and methods: Supramalleolar osteotomy was performed for misaligned callus formation or secondary osteoarthrtitis of the ankle joint in fourteen patients in our institution since 1987. Among these fourteen patients, nine were reviewed, of which three underwent surgery for misaligned callus of the distal third of the tibia measuring more than six degrees and asymptomatic at the time of surgery. The six other patients suffered pain with associated tibiotalar osteoarthritis for four. These six patients also underwent surgery. The nine patients were reviewed clinically and radiographially.

Results: Mean follow-up was 53 months (range 6–202 months). Mean time to bone healing measured radiographically was 12.2 weeks (range 9–18 weeks). The difference in time to healing between closed and open wedge osteotomies was not significant (p=0.1, Student’s test). The difference in the preoperative AOFAS score compared with the last follow-up score was statistically significant (p=0.01) with an improvement in the AOFAS pain score (p=0.03). Function scores of open and closed wedge osteotomies were not statistically different (p=0.5). In the four patients who presented ankle osteoarthritis at the time of surgery, there was no postoperative progression of the joint degradation. Conversely, in two patients whose joint was free of signs of osteoarthritis at the time of surgery, stage I signs appeared. These two patients were reviewed at 46 and 202 months respectively from the osteotomy which in both cases had been performed to prevent the supposedly deleterious effect of a distal tibial callus misaligned 10°.

Conclusion: Open and closed wedge supramalleolar osteotomies are the preferred procedure for distal tibial callus misalignment measuring more than 10° with the reservation that the underlying joints are sufficiently mobile, the advantage of osteotomy over arthrodesis being closely related to this factor. Arthrodesis might however be considered if joint pain predominates the clinical picture.