Management and assessment of prognosis after gastrocnemius disruption in Thoroughbred foals: 28 cases (1993-2007).

REASONS FOR PERFORMING STUDY: Few studies have evaluated the athletic prognosis of foals affected by gastrocnemius disruption. OBJECTIVE: To examine the diagnosis and management of gastrocnemius disruption in Thoroughbred (TB) foals, determine short-term survival rate and assess future racing performance. The hypothesis was that Thoroughbred foals with gastrocnemius disruption are able to perform as racehorses comparably to their age matched maternal siblings. METHODS: The medical records of foals diagnosed with gastrocnemius muscle disruption were reviewed. Information on training and racing was acquired from published works and race records. Paired t tests were utilised to compare performance variables of affected racehorses to their maternal siblings in starts, earnings and earnings/start for their 2- and 3-year-old racing seasons. Fisher's exact tests were employed to determine the association between sex, limb affected, age on admission, degree of caudal reciprocal apparatus dysfunction, concurrent disease, antibiotic therapy, complications, abscess formation and likelihood of entering training or starting a race. RESULTS: Sample size was too small to detect significant differences in performance variables between affected horses and controls. Of 28 foals, 17 (61%) presented with concomitant illness; foals without concurrent disease were more likely to achieve race training or start a race (P = 0.04); 23 (82%) were short-term survivors defined as survival to discharge. Of these 23 survivors, 7 were aged <2 years at the time of the study. Eighty-one percent (13/16) of the survivors that were of racing age were in training or had started a race. CONCLUSIONS: In this population, 82% of TB foals affected with gastrocnemius disruption were able to achieve training or start a race. Foals presenting for gastrocnemius disruption have a high prevalence of concurrent disease processes. POTENTIAL RELEVANCE: The assessment of athletic prognosis and treatment complications provides useful information to clinicians treating gastrocnemius muscle disruption in foals and making recommendations to clientele.

Qualitative and quantitative documentation of the racing performance of 461 Thoroughbred racehorses after arthroscopic removal of dorsoproximal first phalanx osteochondral fractures (1986-1995).

The purpose of this study was to examine the longevity of postoperative careers and quality of performance of 461 Thoroughbred racehorses after arthroscopic removal of dorsoproximal first phalanx (P1) osteochondral fractures. Six hundred and 59 dorsoproximal P1 chip fractures were removed arthroscopically from 574 joints in 461 horses presented for lameness or decreased performance attributed to the chip fractures. Radiological and arthroscopic examination revealed an average of 1.43 fragment sites/horse, 1.15 fragment sites/joint and 1.25 affected joints/horse. Eighty-nine percent of the horses (411/461) raced after surgery and 82% (377/461) did so at the same or higher class. Fifty horses did not race after surgery. Sixty-eight percent of the horses raced in a Stake or Allowance race postoperatively. Data, previously undocumented, establishes that the quantity and quality of performance is not diminished after arthroscopic treatment of dorsoproximal P1 fragmentation. Surgical removal of chip fractures is a means of preserving the economic value of an injured Thoroughbred, allowing a rapid and successful return to racing at the previous level of racing performance.

Racing performance after hemicircumferential periosteal transection for angular limb deformities in thoroughbreds: 199 cases (1987-1989).

Racing records of 199 Thoroughbred foals with angular limb deformities surgically treated by hemicircumferential periosteal transection and elevation (HCPT) from 1987 through 1989 (principals) were compared with records of their 1,017 siblings (controls) for starting status; 2-, 3-, and 4-year-old starts; earnings and earnings per start; and starts percentile ranking number (SPR). Principals had a slightly lower percentage of horses starting a race (45 vs 55%), fewer 2-year-old starts (1.06 vs 1.72), and lower SPR (33.49 vs 49.18), compared with those of controls (P < 0.05). Starting status was significantly (P < 0.05) affected by surgery and the horse's sex, but not by anatomic site treated. Fillies were 1.74 times less likely to start than were colts, regardless of surgery, whereas principal fillies were 2.63 times less likely to start than were control colts. Difference was not detected between principals and controls in 3- or 4-year-old starts; 2-, 3-, or 4-year-old earnings, or earnings per start. Horses treated with distal metacarpal/metatarsal HCPT had fewer 2-year-old starts (1.09 vs 2.19), but did not have a significantly different SPR or lower starting percentage, compared with values for controls. Horses treated with distal radial HCPT had lower starting percentage (48 vs 55%), fewer 2-year-old starts (1.22 vs 1.70), and lower SPR (32.53 vs 53.32), compared with those of controls.(ABSTRACT TRUNCATED AT 250 WORDS)