A retrospective study of the effect of single dose intra-articular hyaluronic acid injection on postoperative recovery in dogs undergoing stifle surgery

Abstract

Hyarulonic acid (HA) is an abundant molecule found in synovial fluid and plays an important role as a lubricant
and shock absorber for the joints. Nonetheless, the effects of synovial fluid replacement with HA after canine stifle
surgery remains elusive. A retrospective study was conducted on 54 small breed dogs with either medial patellar
luxation (MPL) or cranial cruciate ligament ruptures (CCLR). Dogs were classified as HA (21 with MPL-HA and 16
with CCLR-HA) or control (10 with MPL-C and 7 with CCLR-C) groups. The weight bearing score, lameness score, and
pain scores were compared between HA and control groups on 1, 3, 7, 14 and 28 days post-operation. Interestingly, the
weight bearing scores at 1 and 7 days post-operation were significantly different between MPL-C and MPL-HA (D1:
4.0±0.0 vs 3.2±0.1, P-value <0.01; D7: 2.8±0.2 vs 2.3±0.1, P-value = 0.038) and between CCLR-C and CCLR-HA (D1:
4.0±0.0 vs 3.7±0.1, P-value = 0.02; D7: 3.2±0.2 vs 2.3±0.1, P-value = 0.02). The lameness score on D28 was significantly
different between MPL-C (1.00.2) and MPL-HA (0.50.1; P-value = 0.045) (Figure 2). However, there was no difference
in lameness scores between CCLR-C and CCLR-HA on any assessed day. Pain on palpation was not different between
control and HA-treated groups. The present study suggests that synovial fluid replacement with an intra-articular HA
injection provides beneficial effects in dogs that have undergone stifle surgery for correction of MPL and CCLR.
Optimal frequency of HA administration warrants further study.