Pes varus correction in Dachshunds using a hybrid external fixator.

OBJECTIVE

To describe surgical correction of pes varus deformity in Dachshunds by acute medial opening wedge osteotomy of the distal aspect of the tibia stabilized with a hybrid external skeletal fixator (HESF), and report clinical and radiographic outcomes.

STUDY DESIGN

Multicenter, retrospective clinical study.

ANIMALS

Immature Dachshunds (n=13) with pes varus deformity.

METHODS

Limb function and lameness scores were assigned before and after surgery, and correction was determined visually at surgery. Tibiotarsal joint orientation (TTJO) and medial and lateral tibial cortex lengths, measured on radiographs of deformed and normal (when available) limbs, were compared before correction and after fixator removal.

RESULTS

Pes varus deformities (n=14) were corrected; 93% had good to excellent clinical outcome. None of the dogs had a normal preoperative gait. Mean TTJO of abnormal and normal tibiae before surgery were 29 degrees varus (median, 28 degrees), and 12 degrees valgus (median, 12 degrees). Angular correction ranged from 20 degrees to 51 degrees (mean, 36+/-8 degrees; median, 36 degrees). Mean TTJO after fixator removal was 7 degrees valgus (median, 7 degrees). Two dogs had minor transient postoperative complications whereas 3 had major complications; only 1 of which was resolved.

CONCLUSIONS

Pes varus deformity in Dachshunds can be corrected by acute medial opening wedge osteotomy of the distal aspect of the tibia stabilized by HESF. Technique modifications are needed to improve correction precision.

CLINICAL RELEVANCE

Visual inspection of limb alignment during surgery resulted in good to excellent clinical outcomes; however, 91% of tibiae were under- or overcorrected (mean, 6 degrees; median, 5 degrees). Limb alignment should be based on evaluation of immediate postoperative TTJO measurements, not solely on intraoperative visual assessment.