Clinical presentation and surgical repair of traumatic lateral patellar luxation associated with a complete tear of the vastus medialis muscle in a neonatal Cob foal

Patellar luxation associated with traumatic injury is rare in the horse, and surgical correction has not been adequately described. This case report describes the clinical findings associated with traumatic lateral patellar luxation in a 2-day-old cob colt, and the technique used for successful surgical repair. A combination of computed tomography (CT), radiography and ultrasound was used to diagnose lateral luxation of the patella due to a complete tear of the vastus medialis muscle. All patellar ligaments were intact and no congenital abnormalities associated with the patellar luxation were present. Surgical correction of the patellar luxation was achieved using a lateral release of the patella performed by transection of the lateral femoropatellar ligament along with overlying fascia, and stabilisation of the patella by medial imbrication of the medial patellar ligament and parapatellar fascia to the distal tendon of the sartorius muscle. Radiographs at 18 weeks of age showed the patella in a normal position in a well-developed trochlear groove. At 1 year of age the foal was walking and trotting sound, with normal range of motion of the affected stifle.     

Distal luxation of the patella in a horse

A 19-year-old Thoroughbred gelding presented with sudden onset, non-weight bearing lameness in the right hindlimb. Radiography confirmed distal luxation of the patella, which was replaced into its normal anatomical location under general anaesthesia. There were no pathological sequelae noted on follow-up examination 9 months after the initial injury. To our knowledge, this is a rare manifestation of patellar luxation, only reported once previously in the equine literature.     

Posterior lens luxation with associated glaucoma in a pony

Secondary lens luxation is an infrequent consequence of equine recurrent uveitis (ERU). This Case Report describes a pony with posterior lens luxation with associated glaucoma, thought to be secondary to ERU.     

Successful closed reduction and conservative management with traumatic elbow luxation and medial collateral ligament rupture in an equid

A 9-year-old donkey jenny (212 kg) presented with an acute, nonweight-bearing left forelimb lameness of 24- to 36-h duration. The limb was held in flexion and abduction, with the toe above the ground, and was unable to be manually straightened. There was significant palpable swelling along the medial aspect of the elbow joint. Radiographic evaluation revealed a medial luxation of the elbow joint with rupture of the medial collateral ligament. Closed reduction was accomplished under injectable anaesthesia without complication. The patient was weight-bearing and comfortable on the limb immediately upon recovery from anaesthesia. The jenny was tied and kept standing for 60 days. Full limb bandages, splints (extending proximal to the scapula), hobbles, NSAIDs and cold laser therapy were utilised, decreased and discontinued. At 74 days, a rehab programme was initiated. At 8 months post-injury, the patient was not lame and was back to her previous level of exercise. Although elbow luxation has been described as having a guarded prognosis, there has now been success in 4/5 (80%) reported cases when treatment has been attempted. Closed reduction without surgical intervention in adult animals with elbow luxation can be successful, likely dependent on the level of associated injury.     

Pre- and postoperative radiographic and computed tomographic evaluation of dogs with medial patellar luxation

OBJECTIVE: To quantify, using radiographic and computed tomographic (CT) techniques, the effects of surgical procedures most commonly combined to treat dogs with medial patellar luxation (MPL). STUDY DESIGN: Prospective study. METHODS: Six dogs with 8 MPL were studied. Radiographs and CT of the pelvic limbs were obtained before and immediately after soft-tissue reconstruction, trochlear wedge recession, and tibial crest transposition. Radiographic measurements included angle of inclination, Norberg angle, quadriceps angle (QA), anteversion angle, ratio of the length of the patellar tendon (PT) to the length of the patella, and change in patella tendon angle. CT measurements included angle of inclination, Norberg angle, QA, anteversion angle, depth of the femoral trochlear groove, ratio of the middle femoral trochlear groove depth to the patella thickness, and tibial crest alignment. RESULTS: Conformation of the coxofemoral joint was not affected by surgery. Surgical treatment corrected the QA by 33-58%. Trochlear wedge recession was most effective in deepening the proximal trochlea by 103.5%. The ratio of the middle femoral trochlear groove depth to the thickness of the patella postoperatively resulted in 50% coverage of the patella. Tibial crest transposition resulted in caudalization of the PT by 8.5+/-3.0 degrees, with lateralization of the tibial tuberosity of 11.3 degrees. CONCLUSION: The effects of surgery for MPL can be quantified with radiographic and CT measurements. Surgical correction restored the alignment of the quadriceps and adequately deepened the femoral trochlear groove. Tibial crest transposition resulted in caudalization of the patella tendon and lateralization of the tibial tuberosity. CLINICAL RELEVANCE: These pilot data quantified the effects of surgical procedures most commonly combined to treat MPL. We hope to use these measurements to correlate surgical treatment with functional outcome and postoperative occurrence of luxation.     

Treatment of coxofemoral luxation in a mature Welsh pony by femoral head ostectomy: Long‐term outcome

A 233 kg, 4‐year‐old Welsh pony stallion presented with a unilateral coxofemoral luxation and a history of previous upward fixation of the patella. This condition was surgically managed by femoral head ostectomy using a craniodorsal approach to the luxated coxofemoral joint, without greater trochanteric osteotomy. Immediate improvement in weightbearing was observed after surgery and primary intention healing was recorded. Long‐term outcome, 4 years after surgery, was assessed by radiographic, ultrasonographic and lameness examination. The pony was in good body condition and the initial weight of this patient was restored. Despite fetlock hyperlaxity of the contralateral hindlimb, amyotrophy and mechanical lameness of the affected hindlimb, the pony showed evident comfort without apparent signs of pain and was able to trot and gallop. Bone callus was observed at imaging examination.     

Successful closed reduction of an atlantoaxial luxation in a mature Warmblood horse

A 5‐year‐old Warmblood mare was presented to the clinic 8 h after being found by the owners with luxation of the second cervical vertebra. Clinically, the horse showed an extended posture and reduced movement of the head and neck. A defined lateral swelling of the neck at the level of the first cervical vertebrae was evident. Successful reduction was achieved with the horse under general anaesthesia in lateral recumbency using an electrically powered hand pallet truck. The mare showed no neurological disorders before or after reduction. Seven months after the incident the mare could be ridden and exhibited no functional abnormalities relating to the neck.     

Successful treatment of a severely contaminated open metatarsophalangeal joint luxation by arthrodesis

A horse with an open medial luxation of the left metatarsophalangeal joint with extensive cartilage and soft tissue damage and severe contamination of the wound was treated with a two-stage approach. In the first stage, the lesion was cleaned, the luxation was reduced, the wound was sutured and the limb was kept in a cast for a total time of 56 days. In the second stage, an arthrodesis of the affected joint was carried out, using a 13-hole broad 4.5 LCP plate. The limb was then kept in a cast for an additional total time of 56 days. At 70 days after the arthrodesis, the horse was brought in for a final check-up, and only a mechanical lameness remained at that time. No significant complications occurred. Previous case reports on the treatment of metatarso-/metacarpophalangeal luxations include neither cases as severe as the one presented here nor treatment by fetlock arthrodesis. This case illustrates that horses with a complicated, open luxation of the fetlock can be salvaged for breeding purposes.     

Traumatic coccygeal luxation and distal amputation of the tail of an Appaloosa mare

A 17‐year‐old Appaloosa mare presented to the emergency service for acute, traumatic, partial amputation of the tail at the level of the ninth coccygeal vertebra. The patient did not have tail or anal tone and did not respond to sharp stimulation of skin in the perineal region. Two grade 1 rectal tears were found during rectal palpation. Radiographs revealed dislocation of the second (Cd2) and third (Cd3) caudal vertebrae. The patient was treated with antibiotics, an anti‐inflammatory drug and stall confinement. The ninth caudal vertebra was surgically removed to facilitate closure of skin over the wound. When the mare was discharged after 7 days of hospitalisation, she had regained partial sensation of the perineum and partial function of the internal and external anal sphincters. At re‐evaluation one year following injury, the mare was able to move her tail laterally and had regained sensation of her perineum and tail; however, she still was unable to lift her tail.     

Surgical treatment of tarsometatarsal joint luxation in a miniature horse foal

A 2-week-old Miniature Horse foal was referred for evaluation and treatment of a luxated right tarsometatarsal joint. Treatment consisted of closed reduction and internal fixation using two partially threaded Steinmann pins placed in normograde fashion through the tuber calcis into the proximal third metatarsus. Traumatic luxation has been reported to occur in the tarsocrural, proximal intertarsal and tarsometatarsal joints within the equine tarsus. Treatment for luxation of the distal intertarsal joint has not been documented. The treatment method most commonly suggested for tarsal luxation is closed reduction and cast immobilisation. Internal fixation using lag screws and plating has also been described. A combination of internal fixation and external coaptation is thought to achieve maximal stability and allow faster convalescence in cases of tarsal luxation. This case report describes for the first time a technique using two Steinmann pins to achieve successful internal fixation of a traumatic tarsometatarsal joint luxation in a 2-week-old Miniature Horse foal.     

Successful surgical management of a medial humeral epicondyle fracture in a Thoroughbred foal

A 2-week-old 75 kg Thoroughbred filly was presented for the investigation of an acute forelimb lameness. Radiographs revealed a fracture of the medial epicondylar physis of the left humerus (Salter–Harris type II fracture). The fragment was removed via arthrotomy under general anaesthesia. Two months post-operatively, the foal was sound and at 2 years had resumed normal turn out. This case report describes a previously unreported surgical treatment for a fracture of the medial epicondylar physis in a foal.     

Treatment of a congenital lateral patellar luxation by recession trochleoplasty in a donkey foal

The present report describes the surgical treatment of a congenital lateral patellar luxation in a 6-month-old female donkey foal. The foal was presented with a slight crouched position, muscle atrophy, moderate lameness, reluctance to flex the right hindlimb at a walk and slight effusion of the right stifle joint. The foal responded painfully to the stifle flexion test. Irreducible lateral luxation of the right patella was confirmed on physical examination and radiography. The animal was treated surgically by recession trochleoplasty and imbrication of the medial joint capsule. The animal gradually improved after surgery, and good clinical results were reported after 6 months post-operatively. In conclusion, congenital lateral luxation of the patella should be considered as a congenital cause of lameness in donkeys and surgical repair by recession trochleoplasty and medial imbrication of the joint capsule can be helpful to treat this problem.     

Severe hypophosphataemia associated with the management of hyperlipaemia in a miniature pony

This report describes a case of severe hypophosphataemia associated with the management of hyperlipaemia in a miniature pony following colic surgery. Clinical signs attributed to hypophosphataemia included obtundation, anorexia, tachycardia, tachypnoea and generalised muscle fasciculations. Hyperlipaemia was managed with enteral and partial parenteral nutrition; insulin was also administered to control hyperglycaemia after the initiation of caloric support. Specific therapy for hypophosphataemia consisted of parenteral potassium phosphate at 0.03 mmol/kg bwt/h (i.v.). The pony made a full recovery without further complications. Hypophosphataemia may be an under‐recognised clinical problem in certain populations of critically ill equids, such as those with hyperlipaemia and receiving insulin as part of their management. The routine measurement of phosphate concentration in these cases is recommended.     

Mesh repair of a large traumatic lateral abdominal wall hernia in an 8‐day‐old foal

An 8‐day‐old French trotter colt was admitted with a traumatic lateral abdominal wall hernia with reducible intestinal content. A 15 cm long full thickness tear was identified in both the internal abdominal oblique and transverse abdominal muscles. This case report describes the surgical repair of the hernia using a polypropylene mesh.     

Surgical treatment of synovial osteochondromatosis in the middle carpal joint of a pony

A 9‐year‐old Paint pony gelding presented for signs of left carpal swelling of 1–2 weeks' duration. Radiographic, ultrasonographic and arthroscopic evaluation of the left carpus was consistent with synovial osteochondromatosis. This presumptive clinical diagnosis was confirmed histopathologically. Arthroscopic removal of the osteochondral bodies resulted in resolution of the carpal effusion and return to previous athletic activity by 4.5 months post operatively. Arthroscopic removal of osteochondral bodies is the treatment of choice in cases of suspected synovial osteochondromatosis.     

Atipamezole in the management of detomidine overdose in a pony

OBSERVATIONS: A pony undergoing elective castration accidentally received an overdose of IV detomidine (200 microg kg(-1)) before anaesthesia was induced with ketamine and midazolam. A further 100 microg kg(-1) IV dose of detomidine was administered during anaesthesia. The mistake was recognized only when the animal failed to recover from anaesthesia in the expected time. The overdose (300 microg kg(-1) in total) was treated successfully with atipamezole, initially given IV and subsequently IM and titrated to effect to a total dose of 1100 microg kg(-1). The pony regained the standing position. A further injection of atipamezole (76 microg kg(-1) IM) was given 5 hours later to counteract slight signs of re-sedation. CONCLUSIONS: Atipamezole proved an effective antagonist for detomidine in a pony at an initial dose 3.65 x and a final total dose 3.9 x greater than the alpha2 agonist.     

Surgical management of suspected congenital luxation of the radial head in three dogs

Abstract

CASE HISTORIES: Three dogs, aged between 11 and 20 weeks, were presented with unilateral forelimb lameness, with an associated bony prominence on the lateral elbow.

CLINICAL FINDINGS AND DIAGNOSIS: Radiographs revealed a caudolateral luxation of the radial head in all cases, consistent with a diagnosis of suspected congenital luxation of the radial head. Surgical reduction and stabilisation involved open reduction of the radial head, and in two cases the use of a trans articular pin.

CLINICAL RELEVANCE: Congenital luxation of the radial head is an uncommon condition that has conflicting reports in the literature regarding its cause, heritability, breed predisposition, treatment and prognosis. The three cases here occurred in young dogs of English Bull Terrier, Jack Russell Terrier, and Staffordshire Bull Terrier breeds. Surgical reduction and stabilisation provided successful outcomes, in all cases. Only six cases of congenital luxation of the radial head managed surgically have previously been reported in the literature.