Clinical Experiences with Radial Shock Wave Therapy in Performance Horses

statistics were obtained from Standardbred Canada’s Information Technology Division. Each of the 11 conditions treated were analyzed separately (Tables 1-7 ) as well as collectively (Figures 2-4).

Results

Seventy performance horses (68 Standardbreds, 1 Thoroughbred, 1 Arabian, 52 males, 18 females), were included in this study. Many horses had multiple problems on one leg or on multiple legs and most were chronic recurrent soft tissue injuries. Many horses already had previous forms of treatment and most had guarded prognoses with a high reoccurrence rate and poor response to other medical or surgical treatments. Eleven different lameness conditions (Figure 2) were evaluated including suspensory desmitis (33), superficial digital flexor tendinitis (21), fractures (8), sesamoiditis type 2 (4), distal sesamoidean ligament desmitis (3), inferior check ligament desmitis (3), exostoses or splints(3), dorsal metacarpal disease (1), joint synovitis/degenerative joint disease (9), proliferative synovitis (1), and plantar ligament desmitis (1). Suspensory desmitis and superficial digital flexor tendonitis comprised 77% of cases treated. Lameness grades varied from grade 1-5 (AAEP 1-5 scale).
Individual conditions compared had higher success rates (Table 7), but because of a frequent combination of lameness conditions or multiple limb involvement, the overall comparisons gave slightly lower success rates. Overall success rates for treatments with RSWT (Figure 3), as defined by clinically assigned scores, yielded 66% success rate (46/70) and a 34% failure rate (24/70). In order to be a successful case, a clinical score of 12 or higher (maximum 16) had to be achieved. There were 46 horses rated as successful recording an average score of 13.04 (range 12-16). The 24 failure rated horses had an average score of 7.70 (range 4-11). The percentage of total failure rate (TFR) (Figure 4) showed superficial digital flexor tendinitis accounting for 50% of failed cases (12/24), while suspensory desmitis stood at 29% (7/24), fractures at 13% (3/24) and all others at 8% (2/24).

There were no clinically significant complications seen after treatment of all horses with RSWT. In all horses, the skin surface was warm immediately after treatment and a mild transient swelling developed in some. Subperiosteal and endosteal hemorrhage at the application site was possible on occassion, and rarely, hematoma formation occurred. All horses did return to some level of athletic work for some period of time (short in some cases as lameness persisted or reoccurred).

Discussion

When combined with an appropriate rest and rehabilitation period, Radial Shock Wave Therapy appears to be a safe and effective non invasive treatment for many subacute and chronic lameness conditions in performance horses (especially Standardbreds), with 46 of 70 horses (66%) returning to racing at the same or higher levels after treatment. Most of