Bilateral angular carpal deformity in a dog with craniomandibular osteopathy

A four-month-old West Highland White Terrier was presented to the Small Animal Teaching Hospital at the University of Liverpool with the complaint of a bilateral angular carpal deformity. A 20° valgus deformity was present in both thoracic limbs, centred on the distal radial physes. Both distal ulnas were grossly thickened and there was concomitant thickening of the rostral mandible and calvarium. The dog exhibited signs of resentment on palpation of the mandible and signs of pain were elicited on flexion and extension of both elbow joints. No signs of pain were evident on palpation of the ulnas or calvarium. Radiographic images of both ulnas showed marked amorphous periosteal new bone formation. The distal ulnar physes were closed centrally and both elbow joints had humeroulnar subluxation. Radiographic changes to the calvarium and mandibular rami were consistent with a diagnosis of craniomandibular osteopathy. A bilateral ulna ostectomy was performed to correct the angular limb deformity and elbow subluxations. Histology of the ostectomised pieces showed changes consistent with craniomandibular osteopathy.     

Surgical correction of metacarpophalangeal valgus deformity in an alpaca

A 1-month-old alpaca cria presented with a 13 degree valgus deformity of the left metacarpophalangeal joint. The angular limb deformity was centered on the distal metacarpal physes. Transphyseal bridging of the physes was recommended. Two 2.7 mm cortical bone screws were placed either side of the distal metacarpal physes and a figure of eight wire was placed medially around the screw heads. The screws extended through the medial metacarpus into the axial cortex of the lateral metacarpus. Seven weeks after surgery the limb was straight and the screws and wire were removed. Transphyseal bridging of the distal metacarpal physes can be effectively used for the treatment of metacarpophalangeal valgus in crias with open physes.     

Bilateral carpus valgus with cranial bowing of the distal radius in a foal

Bilateral carpus valgus with concomitant outward rotation and cranial bowing of the distal radii was diagnosed in a crossbred foal. The foal was not lame on admission and showed no radiographic evidence of carpal bone abnormalities. Surgery was limited to the most severely affected leg, and consisted of a combination of growth promotion (periosteal transection and stripping) and temporary physeal retardation (transphyseal bridging) procedures. Correction of the valgus deformity was nearly complete in the operated limb and substantial improvement was observed in the cranial bowing and outward rotation in both limbs, five months postoperatively.     

Bilateral wedge ostectomy on an 18-month-old llama with severe bilateral carpal valgus.

An 18-month-old llama was admitted with severe (45 degrees and 40 degrees) bilateral carpal valgus. The llama had grown normally until it was 6 months old, when the carpal deviations had commenced. Radiography revealed abnormalities at the distal ulnar physes. Premature closure of these physes or abnormal distal ulnar growth may have been the cause of the carpal valgus. The owners requested surgical correction of the condition. Medial wedge osteotomies of each radius were performed 3 weeks apart. Internal fixation of the osteotomized radial bones was accomplished with small right-angled T plates, and the limbs were placed in full-limb casts for 3 weeks and tube casts for 3 more weeks. Both limbs healed in straight alignment, and the llama was able to walk and run normally. Dorsal subluxation of the right radiocarpal joint was noticed after the operation. This was believed to be caused by the uncorrected dorsal bowing of the distal portion of the radius, which had occurred secondary to the severe carpal valgus.     

Effect of hemi-circumferential periosteal transection and elevation in foals with experimentally induced angular limb deformities

OBJECTIVE: To evaluate the effect of hemi-circumferential periosteal transection and elevation (HCPTE) in foals with, experimentally induced angular limb deformities. DESIGN: Prospective study. ANIMALS: 10 healthy foals. PROCEDURE: When foals were 30 days old, transphyseal bridge implants were placed on the lateral aspects of both distal radial physes. At 90 days of age (or when 15 degrees of angulation had developed), implants were removed, and HCPTE was performed on 1 limb. Foals were confined in small pens after surgery; the front feet of the foals were rasped weekly to maintain medial-to-lateral hoof wall balance. Dorsopalmar radiographic projections of the carpi were obtained before HCPTE and 2, 4, 6, 8, and 48 weeks later. RESULTS: At the time of transphyseal bridge removal and HCPTE, both treated and control limbs were observed to have a significantly greater carpal valgus, compared with the initial degree of angulation at 30 days of age. Following HCPTE or sham surgery, all limbs straightened over the subsequent 2 months of the study. Median angulation was not significantly different between treated and control limbs at any time during the study. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that in foals with experimentally induced limb deformities, HCPTE was no more effective than stall confinement and hoof trimming alone for correction of the deformity.     

Carpal valgus in llamas and alpacas: Retrospective evaluation of patient characteristics,radiographic features and outcomes following surgical treatment

This study evaluated outcomes of surgical treatment for carpal valgus in New World camelids and correlated successful outcome (absence of carpal valgus determined by a veterinarian) with patient characteristics and radiographic features. Univariable and multivariable analyses of retrospective case data in 19 camelids (33 limbs) treated for carpal valgus between 1987 and 2010 revealed that procedures incorporating a distal radial transphyseal bridge were more likely (P = 0.03) to result in success after a single surgical procedure. A greater degree of angulation (> 19°, P = 0.02) and younger age at surgery (< 4 months, P = 0.03) were associated with unsuccessful outcome. Overall, 74% of limbs straightened, 15% overcorrected, and 11% had persistent valgus following surgical intervention. To straighten, 22% of limbs required multiple procedures, not including implant removal. According to owners, valgus returned following implant removal in 4 limbs that had straightened after surgery.     

Complete ulnas and fibulas in a pony foal

Complete ulnas and fibulas were found in a 10-month-old Welsh Pony examined because of severe flexural deformity, with carpal and tarsal valgus deformities, in all limbs. Presence of these normally vestigial structures is considered a form of atavism. At one week of age, periosteal transection was performed for the angular deformity, resulting in no improvement. When performing this procedure, the authors recommend transection of these vestigial structures if present.     

Periosteal transection and stripping for treatment of angular limb deformities in foals: clinical observations

Correction was attempted in 27 foals (41 limbs) with angular deformities at the carpal region (35 limbs), metatarsophalangeal region (5 limbs) and distal end of the tibia (1 limb) by hemicircumferential transection of the periosteum (HCTP) and periosteal stripping (PS). Successful outcome was determined by straight limbs and soundness, which was achieved in 81.5% of the cases, with 60% of the horses in performance training. Follow-up evaluation for all foals was completed at various times after physiologic closure of the physes. In none of the limbs was the deformity overcorrected. Owners of foals with carpal region deviations corrected by means of HCTP and PS were satisfied with the result. The cosmetic appearance of the surgical site was excellent. The HCTP and PS adequately corrected greater degrees of carpal region deformity and greater degrees of deformity in older foals than previously reported with this or other surgical techniques.     

Ulnar ostectomy decreases the stability of canine cadaver carpi as assessed with stress radiography

Distal ulnar ostectomy may be performed palliatively in patients with distal ulnar osteosarcoma. Concurrent arthrodesis of the carpus has been proposed to counteract joint instability following transection of carpal ligaments associated with removal of the distal ulna. The objective of this prospective one group pretest, posttest study was to assess stability of the carpus following distal ulnar ostectomy using pre‐ and postoperative stress radiographic views in a group of canine cadaver limbs. Seven thoracic limbs from six canine cadavers weighing more than 20 kg were obtained. Lateral and dorsopalmar, extended lateral, medial stress, and lateral stress radiographs were made before and after distal ulnar ostectomy. Presurgical canine cadaver carpal angle measurements were as follows (mean ± standard deviation): extension 205.9° ± 5.4; medial stress 25.1° ± 5.7; and lateral stress 13.3° ± 5.2°. Cadaver limb joint angles exceeded those previously reported in live dogs. A significant increase in carpal angle was noted following ulnar ostectomy. The mean increases in carpal angle were as follows: (mean ± standard deviation (95% confidence interval)): extension 6.2° ± 4.9 (2.6–9.8) (P = 0.007); medial stress 3.2° ± 3.0 (1.0–5.5) (P = 0.015); lateral stress 6.2° ± 5.2 (2.4–10.1) (P = 0.010). Findings from this cadaver study support the use of supplementary stabilization for clinical patients undergoing distal ulnar ostectomy. Future studies are needed in clinical patients to evaluate changes in limb positioning and gait associated with distal ulnar ostectomy.     

ULNAR METAPHYSEAL OSTEOCHONDROSIS IN SEVEN CAPTIVE BRED CHEETAHS (ACINONYX JUBATUS)

Distal ulna metaphyseal osteochondrosis was identified in seven captive bred cheetahs raised in Australia between 1984 and 2005. The disorder was characterized by bilateral carpal valgus conformation. In the metaphyseal region of the distal ulnae, an osteolucent defect that appeared as a proximal extension of the lucent physis was identified radiographically between 6 and 10 months of age. Ulna ostectomy was done to correct the angular limb deformity. Histologically, changes were identified in the osteolucent lesion that resembled osteochondrosis. We propose that the condition is probably familial and/or dietary in origin.     

Unusual Polydactylism in a Foal: A Case Report

A 2 month old quarter horse colt had multiple skeletal abnormalities of the left fore limb, including two supernumerary metacarpal bones, two supernumerary carpal bones, abnormal carpal bone development, and a valgus deformity originating at the carpal joint. The largest supernumerary metacarpal bone was removed completely, a portion of the smaller supernumerary metacarpal bone was removed, and the leg was placed in a tube cast. Surgical treatment improved the clinical appearance and prevented further injury to the limb. The carpal joint width remained increased but the carpal valgus deformity partially responded to hemicircumferential periosteal transection. The foal was sound 2 1/2 years after surgery.     

Single transphyseal screws for the correction of moderate to severe angular limb deformities in 28 Thoroughbred foals

This study reports on the effective use of a single transphyseal screw for the treatment of moderate to severe angular limb deformities (ALDs) of the fetlocks and carpi of 28 young Thoroughbred foals. The objective was to evaluate the surgical management of foals with moderate to severe ALDs treated with single transphyseal screws. Evaluation of medical records of 28 Thoroughbred foals treated with single transphyseal screws placed across the distal radial, metacarpal and metatarsal physes was undertaken. The angle of joint deviation was measured prior to implantation and at removal of the implants, and the degree of improvement was calculated. A total of 39 screws were placed: 24 in the distal metacarpus or metatarsus and 15 in the distal radial physis. Varus or valgus deformities in the fetlock improved by 4–5° over a period of 15–30 days. Varus or valgus deformities in the carpi improved by 8–11° in 11–56 days. One case failed to improve adequately due to implant infection. Single transphyseal screws were effective in treating moderate to severe varus and valgus ALD of the fetlocks and carpi in young Thoroughbred foals. Further investigation into their use in the distal radius in young foals is needed. While single transphyseal screws are almost exclusively used by some clinics in the distal metatarsal and metacarpal physes, many clinicians do not use them in the distal radial physis of young foals due to fear of over‐correction, physitis and metaphyseal collapse. This was not observed in any of our cases.     

Treatment of Forelimb Growth Plate Deformity in 11 Dogs by Radial Dome Osteotomy and External Coaptation

Radial dome osteotomy and external coaptation were used to correct forelimb growth deformities with carpal valgus angles of 15 to 43 degrees in 11 dogs (12 forelimbs). Osteotomy sites were clinically healed by week 4. Appearance and function in 10 limbs was good to excellent. The angular deformity recurred in one dog by week 4 due to partial closure of the distal radial growth plate. Carpal valgus recurred in one dog by week 2 because the ulnar osteotomy healed before radial growth ceased.     

Treatment of long bone fractures in South American camelids: 5 cases

An adult llama and four alpacas were referred with long bone fractures. The llama presented with a closed, comminuted fracture of the right metatarsal bones. Two of the alpacas presented with comminuted fractures of the proximal radius. One fracture was closed and one was open. One alpaca had a closed, comminuted fracture of the distal radius, and the final alpaca had a closed, oblique fracture of the metatarsus. A diagnosis was made in each animal on the basis of clinical examination and radiographs. All fractures were managed by open reduction and internal fixation using selective placement of lag screws and dynamic compression plates. Four animals made uneventful recoveries and no long-term complications were encountered. One alpaca was re-admitted for plate failure and non-union of the fracture 5 weeks after surgery. The plate and screws were removed and a transfixation cast was applied. The fracture healed, however the alpaca showed signs of radial nerve paralysis after the cast was removed. With confinement in a small yard, full function gradually returned to the leg over the ensuing 4 months. Using techniques recommended in other species, South American camelids are suitable candidates for long bone fracture repair using open reduction and internal fixation.     

Use of the Ilizarov method of distraction osteogenesis for the treatment of radial hemimelia in a dog

A 6-month-old female crossbred dog with unilateral radial hemimelia was treated with a circular external fixator. During the first surgery, the dog underwent transverse osteotomy through the distal ulnar physis and rotation of the distal ulnar fragment (epiphysis) together with the forepaw in a lateral direction to achieve contact with the end of the proximal ulnar segment (shaft of the ulna); a circular external fixator was then applied. After removal of the fixator, a cast was applied. The initial intent was to preserve mobility of the ulnocarpal joint; however, the joint fused naturally. A second surgery was performed to lengthen the ulna by use of distraction osteogenesis. An Ilizarov external fixator was used, and the ulna was lengthened 25 mm. During the third surgery, osteotomy of the distal portion of the ulna was performed to treat residual deviation of the forepaw. The surgical treatment resulted in satisfactory use of the limb and a better quality of life.     

Morphology and correction of distal tibial valgus deformities

OBJECTIVES: To characterise distal tibial valgus deformities in dogs through physical examination and radiographic evaluation. Methods: In a clinical study of 16 client-owned dogs, twelve unilateral and four bilateral distal tibial valgus deformities were evaluated using palpation and radiographs. The origin and amplitude of angulation, rotation and length deficits if present were measured. Radiographically, fibular length and position in relation to the tibia was compared in affected and clinically normal limbs. The dimensions of the fibular physes were also compared between clinically normal and affected limbs. RESULTS: Rottweilers and Shetland sheepdogs were overrepresented. Valgus deformities ranged from 16 degrees to 48 degrees (median, 32 degrees ) in affected and from 0 degrees to 13 degrees (median, 6 degrees ) in contralateral, clinically normal limbs. Fibular length, fibular position relative to the tibia or physeal dimensions were not statistically different between affected and clinically normal limbs. CONCLUSION AND CLINICAL RELEVANCE: Many distal tibial valgus deformities in dogs are a uniplanar deformity without concurrent craniocaudal or rotational changes or length deficits. A growth cessation in the fibula does not appear to be responsible for the development of the deformity.     

Congenital malformation of the front limbs in a llama (Lama glama): polydactyly in combination with arthrogryposis

A male, 10 month old llama with malformation of both front limbs was presented. Both front limbs had one more digit located medially. The distal phalanx of this additional digit at the left front limb reached the ground by the tip of the keratinzed pad and the toenail. The accessory digit at the right front limb was bent in a 90 degree angle caudolateraly. Beside the digital bones of the accessory digits the second metacarpal bone and the first carpal bone could be detected in both front limbs by radiological examination. Secondary a bilateral slight carpal valgus deformity could be seen.     

In vitro comparison of transfixation and standard full-limb casts for prevention of displacement of a mid-diaphyseal third metacarpal osteotomy site in horses

OBJECTIVE: To compare transfixation and standard full-limb casts for prevention of in vitro displacement of a mid-diaphyseal third metacarpal osteotomy site in horses. SAMPLE POPULATION: 6 forelimbs from 6 horses euthanatized for reasons not related to the musculoskeletal system. PROCEDURE: A 30 degrees osteotomy was performed in the mid-diaphysis of the third metacarpal bone. Two 4.5-mm cortical bone screws were placed across the osteotomy site to maintain alignment during casting. Two 6.35-mm Steinmann pins were placed from a lateral-to-medial direction in the distal aspect of the radius. A full-limb cast that incorporated the pins was applied. An extensometer was positioned in the osteotomy site through a window placed in the dorsal aspect of the cast, and after removal of the screws, displacement was recorded while the limb was axially loaded to 5,340 N (1,200 lb). Pins were removed, and the standard full-limb cast was tested in a similar fashion. RESULTS: The transfixation cast significantly reduced displacement across the osteotomy site at 445 N (100 lb), 1,112 N (250 lb), 2,224 N (500 lb), and 4,448 N (1,000 lb), compared with the standard cast. CONCLUSION AND CLINICAL RELEVANCE: A full-limb transfixation cast provides significantly greater resistance than a standard full-limb cast against axial collapse of a mid-diaphyseal third metacarpal osteotomy site when the bone is placed under axial compression. Placement of full-limb transfixation casts should be considered for the management of unstable fractures of the third metacarpal bone in horses.     

Use of the Wagner apparatus to lengthen the antebrachium of a growing dog

A six-month-old male golden retriever was presented with a shortened radius and ulna and valgus deformity of the carpus secondary to premature closure of the distal radial and ulnar physes. Osteotomies of the radius and ulna were performed and the antebrachium was lengthened over eight weeks using a Wagner apparatus. This external fixation distractor is used in humans for limb-lengthening procedures. In this case, it was used to correct the angular deformity and to lengthen the limb.     

Partial carpal arthrodesis in a 2-year-old alpaca

A 2-year-old alpaca was presented for acute onset right forelimb lameness. Clinical findings included bilateral carpal valgus (more severe in the affected forelimb) and medial instability of the right radio-carpal joint. Surgical treatment consisted of radio-carpal joint arthrodesis, which is presented as a therapeutic option for severe carpal instability secondary to injury to the supporting ligamentous structures of the carpus.