Geometry of the lateral sliding, closing wedge calcaneal osteotomy: review of the two methods and technical tip to minimize shortening.

BACKGROUND

A lateral closing wedge osteotomy is used for correction of varus hindfoot deformities. Since its original description, different techniques and geometries of the calcaneal bone wedge resection have been described. Even though the techniques seem similar, very different final bone architectures result from each technique, the effects of which are not known. This paper explores several of these techniques and the implications in deformity correction as well as the secondary effects of calcaneal shortening.

METHODS

Mathematical and geometric analysis is performed in 2-dimensions for several hypothetical calcaneal osteotomies as described by the original authors. The resulting changes are calculated and compared.

RESULTS

The shape of the bone resection for the lateral closing wedge osteotomy does not result in significantly different final calcaneal architectures. Both techniques studied result in the same amount of calcaneal shortening and deformity correction. However, when lateral calcaneal wedge resection is combined with lateral translation of the tuberosity for additional deformity correction, more calcaneal shortening is seen with posteriorly directed osteotomies than those that are transverse.

CONCLUSION

The lateral closing wedge osteotomy of the calcaneus results in correction of varus hindfoot deformity at the expense of some calcaneal shortening. Lateral translation of the tuberosity may result in additional calcaneal. The clinical effects of calcaneal shortening or medial soft tissue or nerve tethering from these different techniques are unknown and deserve further investigation.

LEVEL OF EVIDENCE: Level V, expert opinion.