What is the likelihood that Thoroughbred foals treated for septic arthritis will race?

REASONS FOR PERFORMING STUDY: Septic arthritis is a serious problem in the neonate, with a poor prognosis being reported for recovery. The impact of neonatal septic arthritis on the likelihood that Thoroughbred (TB) foals will start on a racecourse is not known. HYPOTHESIS: The development of septic arthritis in a TB foal significantly reduces the likelihood that it will race when compared to foals from the same dam. METHODS: Medical records of 69 foals treated for septic arthritis were reviewed. The dam's foaling records were reviewed and lifetime racing records were then retrieved for both the affected foals and at least one of their siblings (controls). Outcomes that were statistically evaluated included discharge from the hospital and whether the foal eventually raced. Univariate analyses of categorical variables were conducted for each outcome. The number of affected and unaffected foals that raced at least once were compared using regression analysis. Survival analysis was used to compare age at first race between the study and comparison groups. RESULTS: Foals with septic arthritis were less likely to start on a racecourse compared to controls (odds ratio [OR] 0.28; 95% confidence interval [CI] 0.12-0.62, P = 0.001), while those foals that were discharged from the hospital were also less likely to start on a racecourse compared to controls (OR 036; CI 0.15-0.83, P = 0.008). The presence of multisystem disease was associated with a decreased likelihood of surviving to be discharged (OR 0.13; 95% CI 0.02-0.90; P = 0.005), but did not affect the likelihood that they would start in at least one race if discharged successfully (OR 0.45; 95% CI 0.04-2.81; P = 0.34) compared to the other foals with septic arthritis. Log-rank comparison of survival curves confirmed that foals discharged following treatment for septic arthritis took significantly longer to start in their first race compared to the sibling population (mean age of study group 1757 days, CI 1604-1909; mean age of sibling group 1273 days, CI 1197-1349; P = 0.0006). CONCLUSIONS: The development of septic arthritis in a TB foal significantly reduces the likelihood that it will start on a racecourse when compared to controls. POTENTIAL RELEVANCE: Accurate figures allowing a realistic assessment of the athletic future of a foal following treatment for septic arthritis are of significance for both owner and treating veterinarian.     

Results of plate fixation of type 1b olecranon fractures in 24 horses

REASONS FOR PERFORMING STUDY: Previous olecranon fracture reports contain a small proportion of type 1b fractures, with only a few repaired by tension band plate fixation. OBJECTIVES: To evaluate subject details, history, clinical findings and outcome of type 1b olecranon fractures in a large group of horses treated by tension band plate fixation. METHODS: Medical records of 77 horses diagnosed with an olecranon fracture were reviewed. Twenty-four horses (31%) were classified as having type 1b olecranon fractures. Clinical details and follow-up results (4-128 months post operatively) were recorded. RESULTS: Treatment included open reduction and internal fixation using a narrow dynamic compression plate (n = 20), conservative therapy (n = 2) and euthanasia (n = 2). Long-term follow-up was available for 16 plated horses. Four were sound and in training and 9 were sound and performing athletically. Articular surface involvement, comminution, open status or removal of anconeal process fragments did not appear to affect prognosis or soundness. CONCLUSIONS: Internal plate fixation provides an excellent prognosis for an animal capable of athletic performance. POTENTIAL RELEVANCE: Describing tension band plate fixation and results offers a method of fracture repair that will improve the treatment and prognosis for type 1b olecranon fractures.     

Surgical repair of rib fractures in 14 neonatal foals: case selection, surgical technique and results

Reasons for performing study: Fractured ribs are encountered quite frequently in newborn Thoroughbred foals, often with fatal outcome. Surgical repair of fractures therefore requires consideration as a means of reducing mortality. Objectives: To evaluate the repair of rib fractures using internal fixation techniques in foals at 2 different equine hospitals following similar diagnostics and case selection. Methods: The records of 14 foals that underwent internal fixation of fracture ribs were reviewed. Subject details, clinical presentation, diagnosis, surgical technique, post operative care and complications were recorded. Follow-up information was obtained in 7 foals. Results: The fractured ribs were reduced and stabilised using reconstruction plate(s), self-tapping cortical screws and cerclage wire in 12 cases, Steinmann pins and cerclage wires in 1 case and both techniques in 1 case. Not every rib was reduced on each case. Surgical reduction was performed on an average of 2 ribs, range 1-3 ribs in each foal. At the time of writing, 4 foals had been sold, one age 2 years was in training and 2 others died from unrelated causes. Conclusions: Our data support the use of surgical stabilisation utilising reconstruction plates, self-tapping cortical screws and cerclage wire for selected cases of thoracic trauma in neonatal foals. The use of Steinmann pins may be suboptimal due to cyclic failure, implant migration and the potential for iatrogenic internal thoracic trauma. Potential relevance: Foals with existing extensive internal thoracic trauma resulting from rib fracture(s), or the potential for such trauma, previously considered to have a guarded to poor prognosis for survival, may be successfully managed with internal fixation of selected fracture sites.     

Retrospective study of outcome following desmotomy of the accessory ligament of the deep digital flexor tendon for type 1 flexural deformity in Thoroughbreds

Objective Determine the long‐term outcome for Thoroughbreds undergoing desmotomy of the accessory ligament of the deep digital flexor tendon (DAL‐DDFT) for type 1 flexural deformity of the distal interphalangeal joint (DIPJ). Design Retrospective matched cohort study Procedure Medical records were retrieved over a 17‐year period for Thoroughbreds that underwent DAL‐DDFT for type 1 flexural deformity. Long‐term outcome was determined by analysis of race records and comparison with maternal siblings. Comparisons between cases and controls included 2‐year‐old, 3‐year‐old and total career performance data. Results There were 46 cases of DAL‐DDFT. The mean age at surgery was 151 days (median 118, range 2–562); 48% of case horses and 77% of 90 controls started in a race. For case horses that did race, the time to first race, total number of starts and prize money per race were not significantly different to maternal siblings. Age at the time of surgery did not alter the likelihood of starting a race. Conclusion Thoroughbreds undergoing DAL‐DDFT for type 1 flexural deformity of the DIPJ are less likely to race when compared with their maternal siblings. For those that do race, the time to first race, total races and earnings per race are not different from controls. There is no evidence to suggest that age at the time of surgery influences the likelihood of racing.     

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.     

Use of dynamic compression plates for treatment of tibial diaphyseal fractures in foals: nine cases (1980-1987)

The medical records of 9 foals less than 4 months old, with fracture of the tibial diaphysis, were reviewed. Open reduction was accomplished by use of 3 approaches; however, a cranial approach was preferred and was used in 7 foals. Two dynamic compression plates were implanted in all foals except the first of this series. The technique of plate luting was used in 7 foals and appeared to improve the ability of implants to resist failure. Complications after surgery included partial or complete failure of fracture fixation (n = 3 foals), osteomyelitis (n = 2 foals), angular limb deformity (n = 2 foals), minor dehiscence of the surgical wound (n = 3 foals), and mild extensor deficits of the injured limb (n = 4 foals). One foal was euthanatized 12 hours after surgery because of complete loss of fracture fixation. All other foals were discharged 10 to 295 days after surgery. One or both plates were subsequently removed in 7 foals. Follow-up information was obtained 6 to 36 months after discharge. Excellent results were reported for 6 foals, and good or fair results were reported for the remaining 2 foals.     

Diaphragmatic Hernia Repair in Three Young Horses

Objective- This clinical report describes surgical correction of diaphragmatic hernia in three young horses.
Study Design- Retrospective investigation of medical records and subsequent racing performance.
Animals- Three young horses with diaphragmatic hernia.
Results- Three young horses with signs of abdominal pain had diaphragmatic hernia causing small intestinal strangulation. The strangulated small intestine was resected and an end-to-end jejuno-jejunal (two horses) or a side-to-side jejuno-cecal anastomosis (one horse) was performed. Diaphragmatic hernias were closed with a continuous suture pattern. All horses recovered and raced. No difference in race records was found between the subject horses and their siblings. One subject horse died of colic at 5 years of age, but the cause of the colic was undetermined. The remaining two horses are in use as broodmares and have produced multiple foals without recurrence of signs of diaphragmatic hernia
Conclusions- Diaphragmatic hernias can be repaired in horses. These horses can achieve race records similar to their siblings and can produce foals without recurrence of signs of diaphragmatic hernia.     

Results of plate fixation of type 5 olecranon fractures in 20 horses

REASONS FOR PERFORMING STUDY: Previous olecranon fracture reports contain a small proportion of type 5 fractures, mostly treated with conservative therapy. OBJECTIVES: To evaluate the clinical details and outcome of type 5 olecranon fractures in a large group of horses treated by tension band plate fixation and to compare results with other treatment methods. METHODS: Medical records of 97 cases, including 32 (33%) classified as type 5, were reviewed. Subject details, history, radiographic findings, treatment and follow-up results (2-146 months post operatively) were recorded. RESULTS: Treatment included open reduction and internal fixation using a narrow or broad dynamic compression plate (n = 20), conservative therapy (n = 7) and euthanasia (n = 5). Long-term follow-up was available in 15 cases treated surgically, of which 2 were sound and in training, 11 sound and performing athletically and 2 unsound. Distal semilunar notch involvement, comminution or open status did not appear to affect prognosis. CONCLUSIONS: Internal plate fixation provides an excellent prognosis for an animal to be capable of athletic performance. POTENTIAL RELEVANCE: Describing tension band plate fixation and results offers a method of fracture repair that should improve treatment and prognosis for type 5 olecranon fractures.     

Surgical management of complete diaphyseal third metacarpal and metatarsal bone fractures: Clinical outcome in 10 mature horses and 11 foals

Reasons for performing study: Osteosynthesis of third metacarpal (McIII) and third metatarsal (MtIII) bone fractures in horses is a surgical challenge and complications surrounding the repair are common. Retrospective studies evaluating surgical repair, complications and outcome are necessary to increase knowledge and improve success of long bone fracture repair in the horse. Objectives: To evaluate clinical findings, surgical repair, post operative complications and outcome of 10 mature horses and 11 foals with McIII or MtIII fractures that were treated with open reduction and internal fixation (ORIF). Methods: Medical records were reviewed and follow‐up information obtained by means of radiographs and/or telephone questionnaire. Results: Survival was achieved in 62% of the horses (3 mature/10 foals). On long‐term evaluation (>6 months) 11 horses (2 mature/9 foals) were fit for their intended activity, one mature horse had a chronic low grade lameness, and one foal was lost to follow‐up because it was sold. The main fracture types were simple transverse (33.3%) or simple oblique (28.6%) and 71.4% of the fractures were open, 3 Type I (one mature/2 foals) and 12 type II (7 mature/5 foals). The preoperative assessment revealed inadequate emergency treatment in 10 horses (5 mature/5 foals; 47.6%). Survival rate of horses with open fractures was 12.5% (1/8) in mature and 85.7% (6/7) in foals. Post operative incisional infection (4 mature, 3 foals) was only managed successfully in 2 foals. Fracture instability related to inadequate fracture fixation technique occurred in 4 horses (all mature) and was always associated with unsuccessful outcome. Conclusions: Age, bodyweight and infection are strongly associated with outcome in treatment of complete McIII/MtIII fractures. Clinical relevance: Rigid fixation using plates and screws can be successful in treatment of closed or open, complete diaphyseal McIII/MtIII fractures in mature horses and foals. Instable fixation, infection and a bodyweight >320 kg are major risk factors for unsuccessful outcome.     

Results of treatment of 145 fractures of the third metacarpal/metatarsal condyles in 135 horses (1986-1994).

The objectives of this study were to correlate condylar fracture characteristics and type of treatment with subsequent capacity for athletic ability, and to determine the characteristics of healing that affect prognosis after fracture fixation. Medical records, post operative radiographic studies and race records were examined for 135 horses sustaining 145 fractures. Sixty-five percent of horses overall started in a race post injury (SPI) in a mean time of 9.7 months with a mean of 13.7 races post injury. Having raced pre-injury did not confer an advantage to starting post injury, though nonstarters pre-injury tended to take longer to return. For horses starting pre- and post injury, 66% improved or maintained their race class level after injury, whereas 64.2% decreased their race earnings post injury. Eighty-five percent of the fractures received internal fixation, of which 70% were complete fractures. Eighty-seven percent of horses with incomplete-nondisplaced fractures treated conservatively raced post injury. The percent SPI for incomplete-nondisplaced, complete-nondisplaced and complete-displaced fractures treated with internal fixation were 74%, 58%, and 60%, respectively. Males (72%) raced post injury more frequently than fillies (53%), and may represent a truer probability of SPI. Spiral fractures tended to take longer until their first start (mean 13.3 months). Fifty-two percent of horses with articular fragments were able to race post injury. Horses were more likely to start if 2-4 month radiographic healing revealed no evidence of the fracture except the presence of lag screws. Based on this series of cases, the majority of horses, with proper treatment, were able to return to racing regardless of fracture characteristic. Prognosis appeared to be affected by the severity of the injury to the joint, the presence of articular comminution and the quality of surgical repair.     

Repair of physeal fractures of the tuber olecranon in the horse, using a tension band method

Physeal fractures of the tuber olecranon of 4 horses were treated, using the tension band method of compression fracture repair. A cortical bone screw and Steinmann pin were placed through the proximal fragment into the distal parent bone parallel to the palmar border of the olecranon. The tension band was placed dorsal to the Steinmann pin and anchored in a hole through the shaft of the ulna 10 cm distal to the tuber olecranon. Of the 4 foals, 2 became pasture sound, 1 is now being worked under saddle, and the 4th showed no signs of lameness 5 months after surgery.     

Lag screw fixation of dorsal cortical stress fractures of the third metacarpal bone in 116 racehorses

Reasons for performing study: The effectiveness and best method to manage dorsal cortical stress fractures is not clear. This study was performed to evaluate the success of lag screw fixation of such fractures in a population of Thoroughbred racehorses. Hypothesis: Lag screw fixation of dorsal cortical stress fractures is an effective surgical procedure allowing racehorses to return to their preoperative level of performance. Methods: The records of 116 racehorses (103 Thoroughbreds) admitted to Equine Medical Centre, California between 1986 and 2008 were assessed. Information obtained from medical records included subject details, limb(s) affected, fracture configuration, length of screw used in repair and presence of concurrent surgical procedures performed. Racing performance was evaluated relative to these factors using Fisher's exact test and nonparametric methods with a level of significance of P<0.05. Results: Of 92 Thoroughbred horses, 83% raced preoperatively and 83% raced post operatively, with 63% having ≥5 starts. There was no statistically significant association between age, gender, limb affected, fracture configuration or presence of concurrent surgery and likelihood of racing post operatively or of having 5 or more starts. The mean earnings per start and the performance index for the 3 races following surgery were lower compared to the 3 races prior to surgery; however, 29 and 45% of horses either improved or did not change their earnings per start and performance index, respectively. Conclusions and potential relevance: Data show that lag screw fixation is successful at restoring ability to race in horses suffering from dorsal cortical stress fractures.     

Dorsomedial articular fracture of the proximal aspect of the third metacarpal bone in standardbred racehorses: seven cases (1978-1990).

Seven Standardbred horses, all pacers, with a mean age of 2.9 years (range, 2 to 4 years), had dorsomedial articular fracture of the proximal aspect of the third metacarpal bone. Fracture caused acute, unilateral, severe lameness after training or racing. Lameness was abolished by midcarpal joint anesthesia in 4 horses. Six horses had a palpable bony swelling, which caused signs of pain. Radiography revealed a nondisplaced, articular, oblique fracture extending distad toward the dorsomedial cortex for a mean distance of 28 mm (range, 15 to 40 mm). In all horses, chronic periosteal proliferative changes, seen near the distal aspect of the fracture, corresponded to palpable bony exostoses and were associated with the medial attachment of the extensor carpi radialis tendon. In 1 horse, internal fixation followed by a 6-month rest resulted in a successful outcome. All other horses were given 3 months' rest without surgery and were not lame. Five horses raced successfully and lowered the lifetime race records, 1 horse was sound and trained successfully, but died of colic, and 1 horse was not lame in early training.     

Factors associated with prognosis for survival and athletic use in foals with septic arthritis: 93 cases (1987-1994).

OBJECTIVE: To identify factors affecting the prognosis for survival and athletic use in foals with septic arthritis. DESIGN: Retrospective study. ANIMALS: 93 foals with septic arthritis. PROCEDURE: Medical records were reviewed to obtain clinical findings, laboratory test results, radiographic findings, treatment method, and outcome. Race records for Thoroughbreds and Standardbreds were evaluated to determine whether foals subsequently raced and whether they raced successfully. RESULTS: 43 foals had 1 affected joint, 44 foals had multiple affected joints, and number of affected joints was not recorded for 6 foals. The femoropatellar and tarsocrural joints were most commonly affected. Osteomyelitis or degenerative joint disease were detected in 59% (46/78) of foals. Failure of passive transfer, pneumonia, and enteritis were common. Foals were treated with lavage, lavage and intra-articular administration of antibiotics, lavage and arthroscopic debridement with or without partial synovectomy, or lavage and arthrotomy to debride infected bone and systemic administration of antibiotics. Seventy-three foals survived to be discharged from hospital, and approximately a third raced. Isolation of Salmonella spp from synovial fluid was associated with an unfavorable prognosis for survival and multisystem disease was associated with an unfavorable prognosis for survival and ability to race; other variables were not significantly associated with survival and ability to race. CONCLUSIONS AND CLINICAL RELEVANCE: With treatment, the prognosis for survival of foals with septic arthritis was favorable, whereas prognosis for ability to race was unfavorable. Multisystem disease, isolation of Salmonella spp from synovial fluid, involvement of multiple joints, and synovial fluid neutrophil count > or = 95% at admission may be of prognostic value.     

Evaluation of transfixation casting for treatment of third metacarpal, third metatarsal, and phalangeal fractures in horses: 37 cases (1994-2004)

OBJECTIVE: To evaluate clinical findings, complications, and outcome of horses and foals with third metacarpal, third metatarsal, or phalangeal fractures that were treated with transfixation casting. DESIGN: Retrospective case series. Animals-29 adult horses and 8 foals with fractures of the third metacarpal or metatarsal bone or the proximal or middle phalanx. PROCEDURES: Medical records were reviewed, and follow-up information was obtained. Data were analyzed by use of logistic regression models for survival, fracture healing, return to intended use, pin loosening, pin hole lysis, and complications associated with pins. RESULTS: In 27 of 35 (77%) horses, the fracture healed and the horse survived, including 10 of 15 third metacarpal or metatarsal bone fractures, 11 of 12 proximal phalanx fractures, and 6 of 8 middle phalanx fractures. Four adult horses sustained a fracture through a pin hole. One horse sustained a pathologic unicortical fracture secondary to a pin hole infec-tion. Increasing body weight, fracture involving 2 joints, nondiaphyseal fracture location, and increasing duration until radiographic union were associated with horses not returning to their intended use. After adjusting for body weight, pin loosening was associated with di-aphyseal pin location, pin hole lysis was associated with number of days with a transfixation cast, and pin complications were associated with hand insertion of pins. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that transfixation casting can be successful in managing fractures distal to the carpus or tarsus in horses. This technique is most suitable for comminuted fractures of the proximal phalanx but can be used for third metacarpal, third metatarsal, or middle phalanx fractures, with or without internal fixation.     

Racing performance after arthroscopic removal of apical sesamoid fracture fragments in Thoroughbred horses age < 2 years: 151 cases (1989--2002)

REASONS FOR PERFORMING STUDY: Studies on arthroscopic removal of apical proximal sesamoid fracture fragments in Thoroughbred (TB) horses age > or = 2 years have reported a high success rate. However, there are no reports documenting the racing prognosis of TB horses that undergo such surgery as weanlings or yearlings. OBJECTIVES: To describe the incidence of apical proximal sesamoid fractures in immature TB horses, age < 2 years and determine probability and quality of racing performance after arthroscopic removal of such fractures in 151 TB weanlings and yearlings. METHODS: The medical records of TB horses age < 2 years that underwent arthroscopic surgery for removal of apical proximal sesamoid fracture fragments were reviewed. Follow-up information was obtained from race records. Student's t tests were used to compare performance variables of operated racehorses to that of their maternal siblings. RESULTS: Ninety-two percent (139/151) of fractures occurred in the hindlimbs and 8% (11/151) in the forelimbs (fracture of both fore- and hindlimb, n = 1). Horses with forelimb fractures had a greatly reduced probability of racing (55%) compared to those with hindlimb fractures (86%). Overall, 84% of the horses raced post operatively and had performance records similar to that of their maternal siblings, 78% (787/1006) of which raced. CONCLUSIONS: Arthroscopic removal of apical proximal sesamoid fracture fragments in TB weanlings and yearlings carries an excellent prognosis for racing in horses with hindlimb fractures and a reduced prognosis in those with forelimb fractures. Medial fractures of the forelimb carry the worst prognosis. POTENTIAL RELEVANCE: The determination of prognosis increases knowledge on apical sesamoid bone fractures and potential for arthroscopic restoration of the ability to race; and enables the value of yearlings for subsequent sale to be established.     

Basic avian bone growth and healing.

There have been few studies on the process of fracture repair in avian species. Most of the information shows similarities between avian and mammalian bone growth and fracture repair, but there are differences. The main finding confirms that fractures must be reduced properly, stabilized, and immobilized with an adequate blood supply to the bone fragments for optimal healing. The return to function of extremities, particularly the legs and wings, is an important consideration when internal fixation methods are used. Causing little or no collateral damage to soft tissue and joint when implanting internal hardware is ideal and reduces the likelihood of impaired function. Whether internal or external fixation methods are used for fracture reduction, the knowledge of avian bone growth and fracture repair is essential for veterinarian understanding and when discussing the healing process with clients.     

Standing removal of the proximal aspect of an olecranon fracture in a mature horse

A 12‐year‐old 450 kg Argentine polo mare presented with a dropped elbow and an unwillingness to bear weight after being kicked by another horse on the lateral aspect of the upper left forelimb. The mare was subsequently diagnosed with a displaced olecranon fracture that did not readily conform to the standard classification systems. Referral for surgical treatment involving open reduction and internal fixation was declined due to financial constraints. Due to the mare being unsuitable for breeding, and conservative treatment of displaced olecranon fractures being deemed to have an overall poor prognosis for return to full athletic performance, another treatment option was sought. Given the fracture configuration, standing surgical removal of the large proximal fragment was performed. The mare returned to full athletic performance 12 months post operatively without lameness. This case report describes an alternative treatment option for selected olecranon fractures.     

Surgical Repair of Mid‐body Proximal Sesamoid Bone Fractures in 25 Horses

Objective— To describe the characteristics of unilateral mid‐body proximal sesamoid bone (PSB) fractures, to determine factors associated with the outcome of horses after surgical repair, and to describe a technique for arthroscopically assisted screw fixation in lag fashion. Study Design— Retrospective case series. Animals— Horses (n=25) with unilateral mid‐body PSB fracture. Methods— Medical records (1996–2006), radiographs, and arthroscopic videos of horses with surgically repaired unilateral mid‐body PSB fractures were reviewed. Retrieved data included signalment, affected limb and PSB, fracture characteristics, and surgical technique. Outcome was established by radiographic assessment of healing and race records; categorical data were analyzed using Fisher's Exact test. Results— Medial forelimb PSBs were most commonly affected (80%). Surgical technique and degree of reduction were significantly associated with outcome; 44% of horses with screw repair and none of the horses with wire fixation raced (P=.047). Factors that may have influenced this outcome were differences in fracture reduction (improved reduction in 22% wire repairs and 88% screw repairs, P=.002) and use of external coaptation (22% wire repair and 88% lag screw repair, P=.002). None of the horses with unimproved reduction raced after surgery. Conclusions— Only 28% of horses with mid‐body PSB fractures raced after surgery. Compared with wire fixation, screw fixation in lag fashion resulted in good reduction and is seemingly a superior repair technique. Clinical Relevance— For mid‐body PSB fractures, arthroscopically assisted screw fixation in lag fashion and external coaptation for anesthesia recovery and initial support provides the best likelihood of return to athletic use.