Management of medial luxation of the shoulder joint in toy-breed dogs using an antiluxation pin placed lateral to the supraspinatus muscle tendon: 20 limbs (2017-2022).

OBJECTIVE: To describe the clinical and diagnostic findings, surgical procedures, and clinical course of dogs with medial shoulder luxation (MSL) treated with a novel method using an antiluxation pin. ANIMALS: 18 client-owned toy-breed dogs (20 treated limbs). CLINICAL PRESENTATION: Toy-breed dogs with MSL were treated with the antiluxation pin (2017 to 2022). The collected data included signalment, cause of luxation, preoperative and follow-up clinical evaluations with lameness scores (LMS), and radiographic and/or CT findings. RESULTS: Toy Poodle was the most represented breed (17 of 18 dogs [94.4%]). The median age was 10 years. One of 18 dogs had a history of trauma. Medial luxation was confirmed in all limbs using radiography or palpation under general anesthesia. Reluxation occurred in 3 limbs at 1, 4, and 30 days after surgery, respectively. Of these 3 limbs, 1 limb underwent revision to replace the original pin and the other 2 limbs underwent no further treatment. One limb with persistent pain underwent 2 revision surgeries to adjust the pin orientation 30 and 72 days after the initial surgery. Eighteen limbs remained unluxated after the initial or revision surgery until the final follow-up (median, 18.5 months; range, 1 to 63 months). The LMS at the final follow-up for the 18 unluxated limbs (mean, 0.5) was significantly lower than the preoperative LMS (mean, 4.5) (P < .01). CLINICAL RELEVANCE: A novel method of the antiluxation pin provides an alternative surgical treatment for MSL in toy-breed dogs that is minimally invasive and technically simple.

Treatment of shoulder joint luxation with glenoid ostectomy in a miniature donkey.

CASE DESCRIPTION: A 13-year-old 128-kg miniature donkey gelding was evaluated for right forelimb lameness of 7 weeks' duration. CLINICAL FINDINGS: Muscular atrophy of the infraspinatus and supraspinatus muscles over the right scapula with a palpable bony prominence over the point of the shoulder was evident. At the walk, the cranial phase of the stride was reduced with adduction of the distal aspect of the limb, dragging of the toe, and lameness (grade, 4/5). Lateral and craniocaudal radiographs of the right shoulder joint revealed lateral luxation of the humerus in relation to the scapula with bony proliferation and remodeling of the humeral head. TREATMENT AND OUTCOME: Glenoid ostectomy was performed. Immediately after surgery, the donkey was able to intermittently stand squarely on the limb but maintained a reduced cranial phase of the stride at the walk. The donkey had no short-term complications and was discharged from the hospital 11 days after surgery. Following discharge, the donkey was confined to a box stall for 60 days, followed by a gradual increase in movement to full pasture turnout. The lameness continued to improve, and at 15 months after surgery the donkey was turned out in pasture and had mild lameness (grade, 3/5) at the trot. Mild muscular atrophy of the supraspinatus and infraspinatus muscles was present with no signs of pain on palpation or manipulation of the limb. Shoulder joint radiography at 15 months after surgery revealed remodeling of the glenoid cavity of the scapula and humeral head with formation of a pseudoarthrosis. CLINICAL RELEVANCE: Glenoid ostectomy should be considered as an alternative to shoulder joint arthrodesis in small equids with shoulder joint luxation. Other indications for this procedure could include chronic osteoarthritis or fractures affecting the shoulder joint.

Long-term outcome following cranial biceps brachii tendon transposition in a dog with a traumatic cranial scapulohumeral luxation.

Background: Cranial luxation of the scapulohumeral has been rarely reported in dogs and there is limited information available regarding surgical management of this condition, particularly with respect to long-term functional outcomes. Case Description: This report describes the successful resolution of a chronic traumatic cranial scapulohumeral joint luxation in a dog that was stabilized by cranial transposition of the biceps brachii tendon of origin. At surgery, an osteotomy of the greater tubercle was performed and a trough was made in the exposed bed of the osteotomy. The transverse humeral ligament was incised, and the bicipital tendon was levered into the trough and secured in that location by reattachment of the greater tubercle using multiple Kirschner wires and a figure-of-eight tension band wire. Postoperatively, the dog was maintained in a Spica splint for 2 weeks. Although surgical reduction was performed 4 months after the original injury, the luxation did not recur and the dog did not have appreciable lameness 14 months following the surgery. Conclusion: Although cranial transposition of the bicipital tendon is an invasive procedure, this dog's scapulohumeral luxation did not recur and the procedure yielded an excellent long-term functional outcome.

Surgical arthrodesis for treatment of chronic shoulder joint luxation in a Vietnamese potbellied pig.

CASE DESCRIPTION: A 4-year-old 55.0-kg (121-lb) spayed female Vietnamese potbellied pig was examined for right forelimb lameness of 2 months' duration that had not resolved following rest and treatment with meloxicam. CLINICAL FINDINGS: The only abnormality identified during physical examination was non-weight-bearing lameness of the right forelimb. Radiographic and CT examinations revealed that the right humerus was displaced laterally and slightly cranial to the glenoid cavity of the scapula with moderate evidence of osteoarthritis. Chronic craniolateral luxation of the right humeral (shoulder) joint was diagnosed. TREATMENT AND OUTCOME: Arthrodesis of the right shoulder joint was performed surgically by a lateral approach. The humeral head was replaced in the glenoid cavity. The joint was immobilized at a 115° angle with two 3.5-mm string-of-pearls orthopedic plates and a 4.5-mm cortical bone screw placed across the joint in lag fashion. The pig recovered from surgery without any complications. At 6 weeks and 5 months after surgery, the pig had the expected mechanical lameness of the right forelimb owing to immobilization of the shoulder joint and radiographic evidence of progressive arthrodesis of that joint. The pig had resumed its usual activities and had only mechanical lameness present 1 year after surgery. CLINICAL RELEVANCE: This report described successful treatment of chronic shoulder joint luxation in an adult Vietnamese potbellied pig by surgical arthrodesis of the affected joint. The described procedure might also be useful for treatment of other debilitating conditions of the shoulder joint, such as severe osteoarthritis or intra-articular fractures, in pigs.

Displacement of an Ununited Medial Humeral Condylar Ossification Centre in the Cat.

A 2-year-old cat was presented with the complaint of acute-onset non-weight-bearing lameness of the right forelimb. When examined, the cat was of short stature and had multiple joint and cartilaginous abnormalities suggestive of chondrodysplasia. The cause of the acute lameness was radiographically identified as a displaced osseous fragment from the medial portion of the right humeral condyle. The features of the osseous fragment were consistent with an ununited medial condylar ossification centre of the distal humerus. Furthermore, a nondisplaced ununited ossified fragment of similar appearance and size was present in the contralateral elbow. Surgical treatment by excision of the displaced fragment resulted in a preinjury level of limb function in the long-term outcome evaluation.

Surgical management of dorsal scapular luxation in three dogs.

Scapular luxation is an uncommon cause of forelimb lameness in dogs and cats. Traumatic rupture of the serratus ventralis muscle allows the scapula to displace dorsally during weight-bearing. Specific documentation regarding clinical presentation and surgical techniques is limited, with no medium- to long-term results of surgical intervention in dogs described. Presented here are three cases of scapular luxation in dogs, treated with a modified surgical technique. Clinical outcome was considered good to excellent, with resolution of lameness and abnormal scapular motion in all three dogs. Medium- and long-term outcomes were assessed in two of the dogs, with an excellent outcome in both cases.

Surgical treatment of scapulohumeral subluxation in an alpaca (Vicugna pacos) using osteotomy of the acromion, open reduction and extracapsular tension sutures.

CASE HISTORY AND CLINICAL FINDINGS: A 3.3-year-old male alpaca, weighing 60 kg was referred for investigation of a severe left forelimb lameness of 4 weeks duration. A scapulohumeral subluxation had been diagnosed radiographically by the referring veterinarian. CLINICAL FINDINGS AND DIAGNOSIS: Based on clinical, ultrasonographic and radiographic findings the diagnosis of cranio-lateral subluxation of the left humeral head was confirmed. In addition, a full thickness lesion (approximately 1×1 cm) of the articular cartilage on the caudomedial aspect of the humeral head was diagnosed by arthroscopy. TREATMENT AND OUTCOME: Treatment included open reduction with internal fixation. Severe muscle contraction and local tissue fibrosis around the scapulohumeral joint (SHJ) required osteotomy of the acromion 3 cm proximal to the distal acromial edge, to allow adequate access. Internal stabilisation was achieved by placing tension band sutures between one cortical screw in the scapular neck and two cortical screws, with washers, craniolaterally on the greater tubercle of the humerus. Post-surgery, a carpal flexion sling was applied with the carpus maintained in 70° flexion for 4 weeks to avoid postoperative weight-bearing. An exercise programme was started 8 days after surgery and continued for 12 weeks. The alpaca had an uneventful postsurgical recovery and showed no lameness after 8 weeks. The long-term outcome was excellent; 21 months after surgery the alpaca was sound and the range of movement of the left SHJ was equal to the right SHJ. CLINICAL RELEVANCE: Even in this chronic case of subluxation of the SHJ of 4 weeks duration, surgical treatment using osteotomy of the acromion, open reduction and internal fixation with extracapsular scapulohumeral tension sutures resulted in an excellent long-term outcome in this alpaca, despite the presence of a cartilage lesion.

Surgical stabilization of shoulder luxation in a pot-bellied pig.

Case Description-A 4.6-month-old pot-bellied pig was evaluated because of non-weight-bearing lameness (grade 5/5) in the right forelimb of 4 days' duration. Clinical Findings-Clinical and radiographic examination revealed a closed, lateral luxation of the right shoulder joint. Treatment and Outcome-Initial attempts at closed reduction failed to provide adequate stability of the shoulder joint. Open reduction and internal fixation by placement of 2 lateral tension sutures with a system designed for canine cranial cruciate ligament repair provided adequate joint stability and a successful outcome. Conclusions and Clinical Relevance-Stabilization of the shoulder joint with lateral tension sutures after open reduction should be considered for management of lateral shoulder luxation in pot-bellied pigs.

Traumatic craniolateral shoulder luxation and fracture of the lesser tubercle of the humerus in a dog.

A five-year old, spayed female, Bearded Collie was presented with a 24-hour history of non-weight-bearing lameness of the right thoracic limb after sustaining vehicular trauma. Radiographs revealed a craniolateral scapulohumeral luxation and a distally and medially displaced fracture of the lesser tubercle of the humerus. Open reduction and internal fixation of the fracture was achieved with lag screw fixation and an anti-rotational Kirschner wire. Surgical repair resulted in compression across the fracture line, anatomic reduction of the articular surface, and a stable scapulohumeral joint following reduction of the humeral head in the glenoid. Six weeks postoperatively, the patient exhibited no evidence of pain or lameness on the right thoracic limb and radiographs revealed complete healing of the fracture and normal articulation of the scapulohumeral joint. This is the first report of a lesser tubercle fracture associated with a craniolateral shoulder luxation. Surgical intervention resulted in the return of full shoulder joint function in this dog.

Scapulohumeral joint luxation in alpacas: 10 cases (2003-2009).

OBJECTIVE: To describe the clinical findings, treatments, and outcome in alpacas treated for scapulohumeral joint luxation (SHJL). DESIGN: Retrospective case series. ANIMALS: 10 alpacas. PROCEDURES: Medical records of alpacas with SHJL that were treated at 2 referral hospitals were reviewed. History, signalment, physical examination results, radiographic findings, treatments, complications, and outcome were evaluated. RESULTS: Records for 8 male and 2 female alpacas with 16 instances of SHJL were reviewed. Three male alpacas each had 2 recurrences of SHJL in the treated limb. The proportion of male alpacas treated for SHJL was significantly greater than the proportion of female alpacas treated for SHJL. Closed reduction was used in 2 female and 3 male alpacas; SHJL reccurred in the 3 males. Stabilization by use of a lateral extracapsular tension band suture technique was performed successfully in 4 male alpacas; in another male alpaca, reluxation caused by self-inflicted trauma occurred postoperatively. In 2 male alpacas, arthrodesis was performed but residual lameness remained 1 year after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: SHJL should be considered as a differential diagnosis in alpacas with thoracic limb lameness. Luxation may occur more frequently in males. A closed reduction technique may be used successfully to treat acute luxations. Extracapsular stabilization by use of the lateral extracapsular tension band suture technique was successful for treatment of recurrent SHJL and SHJL that could not be reduced via closed reduction.

Evaluation of radiographic and genetic aspects of hereditary subluxation of the radial head in Bouviers des Flandres.

OBJECTIVE: To study radiographic and genetic aspects of hereditary radial head subluxation in Bouviers des Flandres. ANIMALS: 26 related Bouviers des Flandres affected with bilateral subluxation of the radial head, 10 unaffected related dogs, and 29 unrelated Bouviers des Flandres with diagnoses of nonskeletal diseases. PROCEDURES: All dogs were radiographically studied, and their DNA was analyzed with a genome-wide screen of 1,536 single nucleotide polymorphisms. In addition, karyotyping was performed in an unaffected dam and its affected offspring. RESULTS: Both forelimbs of affected dogs were disproportionately short with caudolateral subluxation or luxation of the radial head. Angulation of the radial axis at the mid-diaphysis ranged from 9.3 degrees to 30.3 degrees (mean +/- SD, 14.9 +/- 6.1 degrees ), with an estimated age of onset from 0 to 4 months. Poorly defined medial coronoid processes and osteoarthritis of the elbow joint, cranial bowing of the olecranon, and disturbed growth in length of the ulna with sharply demarcated spurs were noticed on radiographs of affected dogs. Genealogical analysis indicated that most affected dogs were closely related, but the mode of inheritance was not clear. The DNA analysis found that 205 single nucleotide polymorphisms were monomorphic in the affected dogs. Conventional chromosome staining revealed no numerical chromosomal aberration. CONCLUSIONS AND CLINICAL RELEVANCE: Congenital radial head luxation and subluxation in the studied Bouviers des Flandres were characterized by angulation of the radial axis leading to caudolateral subluxation of the radial head and insufficient growth of the distal portion of the ulna together with cranial bowing of the olecranon.

Temporary transarticular stabilization with a locking plate for medial shoulder luxation in a dog.

This report describes the temporary fixation of a traumatic shoulder luxation in a large-breed dog using a 3.5-mm Locking Round-Hole Reconstruction Plate (LRHRP) to provide stable internal splinting, allowing healing of the injured ligaments, joint capsule, glenohumeral ligaments, tendons, and muscles for restoration of joint stability. The use of a temporary plate with a locking system should be considered as an option in the treatment of canine shoulder joint luxations with severe tissue damage.

Repair of a coracoid luxation and a tibiotarsal fracture in a bald eagle (Haliaeetus leucocephalus).

A 4.5-kg, adult bald eagle (Haliaeetus leucocephalus) was presented after being found unable to fly. Crepitus was palpated in the left shoulder; however, the wing position was normal. Radiographs revealed caudoventral luxation of the left coracoid, affecting its distal articulation with the clavicle and its proximal articulation with the sternum. The luxation affecting the coracoid-sternum articulation was repaired by using a 4-hole, 1.5-mm T-plate and a 6-hole, 2.0-mm dynamic compression plate (DCP) placed side by side. The luxation affecting the coracoid and the clavicle was repaired by 2 cerclage wires in a simple interrupted pattern. Before a scheduled release, the bird sustained a closed, complete mid diaphyseal transverse fracture of the right tibiotarsus, which most likely occurred during recapture from the flight cage. The fracture was surgically repaired with 2 circumferential cerclage wires, an intramedullary Kirschner wire and one 10-hole, 2.7-mm DCP. The bird was successfully released, 105 days after the first surgery, near the location where it was found.

Stabilisation of medial shoulder instability by imbrication of the subscapularis muscle tendon of insertion.

OBJECTIVES: To evaluate the efficacy of subscapularis muscle tendon of insertion imbrication as a treatment for medial shoulder instability. METHODS: Medial shoulder instability was diagnosed in five dogs. Initial management with medical or arthroscopic treatment failed to fully resolve lameness in four of the cases. Each case was treated by subscapularis muscle tendon of insertion imbrication. An anatomical model of medial shoulder instability was used to assess the effect of subscapularis muscle tendon of insertion imbrication on the angle of abduction of the shoulder. RESULTS: In clinical study, subscapularis muscle tendon of insertion imbrication was performed in five cases. Lameness resolved fully in three cases and partially in two cases. In cadaver study, transection of either the subscapularis muscle tendon of insertion or the subscapularis muscle tendon of insertion and medial glenohumeral ligament significantly increased the angle of abduction. Imbrication of the subscapularis muscle tendon of insertion significantly reduced the angle of abduction. No significant differences were noted between the angle of abduction of normal shoulder and the shoulder with medial shoulder instability treated by subscapularis muscle tendon of insertion imbrication. CLINICAL SIGNIFICANCE: Subscapularis muscle tendon of insertion imbrication is a moderately effective procedure for the management of medial shoulder instability unresponsive to medical and/or arthroscopic management. The angle of abduction of the shoulder was returned to normal in model of medial shoulder instability, following subscapularis muscle tendon of insertion. Subscapularis muscle tendon of insertion imbrication provides a relatively simple method of treating medial shoulder instability in dogs.

Treatment of a shoulder luxation in a forelimb amputee dog.

An eight-year-old, male, thoracic limb amputee Whippet presented with a traumatic lateral luxation of the scapulohumeral joint. Surgical reduction and stabilisation of the shoulder joint by means of a modified Campbell scapulohumeral prosthesis and capsulorrhaphy was unsuccessful and reluxation of the shoulder joint occurred. Subsequent surgical stabilisation using bicipital tendon transposition and a modified Campbell scapulohumeral encircling prosthesis in combination with a novel body cast / Spica splint resulted in a return to satisfactory function of this limb.

Transposition of the biceps tendon to reduce lateral scapulohumeral luxation in three species of nondomestic ruminant.

Open reduction of lateral luxation of the scapulohumeral joint was performed in a Mhorr gazelle (Gazella dama mhorr), a southern pudu (Pudu puda), and an Alpine ibex (Capra ibex ibex) by transposition of the biceps brachii tendon lateral to the greater tubercle of the humerus. The ibex had a very large greater tubercle that required a second osteotomy to allow successful lateral transfer of the tendon. Although all three animals were non-weight bearing in the first 2-3 wk after surgery, ambulation improved at 3 wk and was almost normal by 6 wk after surgery. Postoperative follow-up of 8 yr, 7 mo, and 3 mo in the gazelle, pudu, and ibex, respectively, revealed normal ambulation with no gait deficits. The gazelle was euthanized 8 yr after surgery for unrelated disease and necropsy demonstrated mild to moderate degenerative joint disease. Similar lateral shoulder luxations in comparably sized, nondomestic ruminants, without concurrent fractures or significant joint abnormality, have a good prognosis for return to function after surgical reduction using a biceps tendon transposition.

Radiological study to evaluate suspected scapulohumeral joint dysplasia in Shetland ponies.

A radiological study was performed to test the hypothesis that osteoarthritis of the scapulohumeral joint in Shetland ponies is secondary to shoulder dysplasia. Animals were selected into 3 groups: Group 1: Shetland ponies with a radiological and clinical diagnosis of scapulohumeral osteoarthritis (n = 8); Group 2: Shetland ponies without forelimb lameness (n = 12); Group 3: Horses/ponies without a history or clinical signs of forelimb lameness (n = 22). Anatomical indices were measured from mediolateral radiographs of a scapulohumeral joint from each animal. There was a significant difference in the mean radius of curvature of the glenoid cavity of the scapula (RCG) between the 3 groups (MANOVA test, P = 0.003). The mean RCG of both Group 1 (P = 0.001) and Group 2 (P = 0.022) was significantly greater than that of Group 3. There was no significant effect of group on the radius of curvature of the humeral head or on the Conformity Index. There was a significant effect of group on the Glenoid Ratio (MANOVA test, P = 3 x 10(-6)). The mean Glenoid Ratio was significantly lower in both Group 1 (P = 2 x 10(-6)) and in Group 2 (P = 0.006) than in Group 3. These results indicate that the glenoid cavity of the scapula is 'flatter' and 'shallower' in Shetland ponies which we postulate to be a primary dysplasia in this breed.