Introduction

Sliding humeral osteotomy (SHO) is an accepted treatment for medial compartment disease (MCD) of the canine elbow. The procedure realigns the limb to shift the forces from the medial to the lateral aspect of the elbow, reducing the pressure within the medial compartment. Our objective was to determine the medium-term complication rate with a refined SHO technique to treat end stage MCD and to compare clinical outcome of this technique with and without subtotal coronoid ostectomy (SCO) and fragment removal (FR).

Materials and Methods

Thirty-four dogs (48 limbs) with end stage MCD (Outerbridge ≥ 4) had signalment, lameness score, and preoperative imaging findings recorded. An 8-hole locking stepped SHO plate was applied to the medial aspect of the humerus, stabilizing a transverse mid-diaphyseal humeral osteotomy with modified technique. Outcome measures included lameness score (0–5), manipulation pain score (0–2), force-plate and owner assessment. Measurements were recorded preoperatively, at 6 weeks, at 12 weeks and at 4 to 17 months. Complication rate was compared to that found in the previously published data and intervening transitional methodology.

Results

Of 48 limbs operated, 22 had concomitant SCO+FR. Age was 36.07 ± 29.15 months and body weight ranged 22.3–49.8 kg. Preoperative lameness score and manipulation pain score were 2.15 ± 0.65 and 1.5 ± 0.55 respectively. Lameness improved significantly in all limbs by week 12 (0.23 ± 0.46) and resolved in 42/48 limbs at the last follow-up. There was no difference in outcome with or without SCO+FR. Complication rate was 4.17%, with an incidence of major complications requiring surgical revision of 0.00%. Force-plate data for 21 dogs revealed significant improvement in lameness and velocities at 12 months (P < 0.05). Owner-assessed VAS function scores revealed that all dogs improved significantly across the majority of functional variables at the last follow up.

Discussion

Mid-term outcome measures indicated SHO is associated with significant improvement in lameness and reduction of elbow pain for all patients. Complication rate for refined SHO has been reduced to 4.17% overall complications and 0.00% major complications. We conclude that refined SHO is a valid treatment option with consistently low morbidity for end stage MCD in young to middle age dogs.