pISSN 1598-298X
J Vet Clin 32(1) : 98-100 (2015)
http://dx.doi.org/10.17555/ksvc.2015.02.32.1.98
98
A Modified Stabilization of Medial Shoulder Luxation by Biceps Tendon Transposition in a Dog
Ho-Hyun Lee*, Sung-Ho Yun*, Kwang-Ho Jang* and Young-Sam Kwon*,**1
*Department of Veterinary Surgery, College of Veterinary Medicine, Kyungpook National University, Daegu 702-701, Korea
**Stem Cell Therapeutic Research Institute, Kyungpook National University, Daegu 702-701, Korea (Accepted: February 14, 2015)
Abstract : A 10-year-old intact female Chihuahua weighing 2 kg was presented for complaint of forelimb lameness with non-weight bearing posture. Greater tubercle was palpated medial to its normal location on palpation and crepitation was intermittent with manipulation. On radiographic examination, left medial scapulohumeral joint luxation was found.
Bilateral medial patellar luxations also were found and evaluated as grade III. Surgically, the medial scapulohumeral joint luxation was reduced with transposition of the tendon of the biceps brachii muscle. The patient's gait became normal and non-weight bearing posture was resolved at 6 weeks postoperatively.
Key words : shoulder luxation, biceps tendon, dog.
Introduction
Instability or luxation of scapulohumeral joint arises when loss or damage of the joint is sufficient to cause separation between scapula and humerus. Scapulohumeral luxation is uncommon in dogs and can be associated with trauma or congenital (7). Scapulohumeral joint capsule, glenohumeral liga- ments, and surrounding tendons like supraspinatus, infraspina- tus, teres minor, and subscapularis support scapulohumeral joint. Shoulder rotation and motion are necessary for collab- oration of more than 25 muscles. Approximately two thirds of the movement of the shoulder region occurs from the scapu- lohumeral joint (5). Among these muscles and tendons, biceps tendon and medial and lateral glenohumeral ligaments are significant supporting structures. If these structures are dam- aged or deficient, humeral head may luxate.
Scapulohumeral luxations are named for the direction the humeral head deviates. While cranial and caudal luxations are rare, most common deviations are medial or lateral. Lat- eral glenohumeral ligament and infraspinatus tendon rupture is related with traumatic lateral humeral luxations. Similarly, traumatic medial humeral luxations occur in case of tearing of the medial glenohumeral ligament and subscapularis ten- don. With lateral luxation, the foot has internal rotation, and the greater tubercle is palpable lateral from its normal posi- tion. In medial luxation, the foot is rotated externally and the greater tubercle is palpated medial to its normal location.
Pain and crepitation are evident with shoulder manual exam- ination (6).
With traumatic luxation, concurrent thoracic trauma is com- mon like pulmonary edema, pneumothorax, hemothorax, pul- monary contusions, ribs fracture. Laxity of the shoulder joint
capsule and adjacent ligaments may result in medial instabil- ity and further medial luxation of the humeral head. Shoulder subluxation or instability is associated with incomplete tear- ing of the medial glenohumeral ligament and biceps tendon, distention of the joint capsule, synovitis and degenerative joint disease. And these may cause shoulder pain and lame- ness chronically in dogs. Traumatic luxation can occur in any age or breed or sex of dog. Instability or luxation of scapulo- humeral joint arises in both of large and small breed dogs.
But congenital medial luxation occurs frequently in small and miniature dog breeds. Toy breeds appear to be affected most frequently (4).
Case
A 10-year-old intact female Chihuahua weighing 2 kg was presented for complaint of forelimb lameness with non- weight bearing posture at the Veterinary Medical Teaching Hospital of Kyungpook National University. The patient has had a habit of going up and down her owner’s bed. Then, it has been frequent in recent months and lameness started after falling from bed. The owner visited local animal hospital and had anti-inflammatory medication her for a couple of days.
But the owner felt that it didn’t work.
On physical examination, the patient had standing posture with 3 limbs except left forelimb. Also, it revealed greater tubercle was palpated medial to its normal location on palpa- tion and crepitation was intermittent with manipulation. But it was considered there is no pain during forelimb palpation examination. On radiographic examination of shoulder joint, left medial scapulohumeral joint luxation was found (Fig 2A). However there were no osteophytes in the bicipital groove, subchondral sclerosis of the groove and mineraliza- tion in the biceps tendon on a mediolateral view of the prox- imal humerus. Without any presence of significant abnor-
1Corresponding author.
E-mail: kwon@knu.ac.kr
A Modified Stabilization of Medial Shoulder Luxation by Biceps Tendon Transposition in a Dog 99
malities, left forelimb lameness with non-weight bearing was thought to be caused by the medial luxation of left scapulo- humeral joint. Also both medial displacement of patella were found on orthopedic examination (Grade III).
Surgical reduction of left dislocated shoulder joint was considered. The patient had dorsal recumbency with pre- pared aseptic procedure of wide area centered on the left shoulder joint. Craniomedial skin incision of scapulohumeral joint was performed for biceps tendon transposition. The insertions of the superficial and deep pectoral muscles from humerus were incised and supraspinatus muscle was retracted laterally. The tendon of the coracobrachialis muscle was transected to expose the subscapularis muscle tendon. The tendon of the suprascapularis muscle and the joint capsule was incised. To transpose the biceps tendon, the transverse humeral retinaculum was incised (Fig 1A). A small incision in the joint capsule under the biceps tendon was made to free and move it medially. Two cancellous bone screws were inserted to the medial proximal humerus. Biceps tendon was moved between them and sutured with figure of eight suture method using polyamide suture over the tendon to secure it to the humerus (Fig 1B). The joint capsule was sutured and then the pectoral muscles were sutured to the deltoid fascia.
The subcutaneous tissue and skin were closed routinely.
Orthopedic examinations and radiographs were performed to observe the security and healing process right after sur- gery (Fig 2B) and at 1, 2, and 6 weeks post-operatively. At 2 weeks after operation, lameness of forelimb was still existed.
The patient was able to walk and trot without any forelimb
lameness at 6 weeks after surgery.
Discussion
Several surgical options have been used to medial shoul- der joint luxation. Surgical methods for stabilization of the shoulder joint include transposition of the tendon of the biceps brachii muscle, transposition of the tendon of the supraspina- tus muscle, augmentation of the existing medial collateral ligament by placement of synthetic sutures, imbrication of the tendon of the subscapularis muscles (3), and radiofre- quency-induced thermal modification (5). Hohn et al also uti- lized the biceps barchii tendon for stabilization of 11 medial and 4 lateral luxations in dogs (2). Craig et al recently have described the transfer of a portion of the supraspinatus inser- tion as well as reefing of the medial joint capsule as a treat- ment for medial luxation (1). Among these techniques, the first surgical procedures include transposition of the tendon of the biceps brachii muscle using a bone screw and spiked washer and less commonly, the tendon of the supraspinatus muscle (1). Selection of imbrication of the subscapularis muscle or medial glenohumeral ligament reconstruction may largely be a function of the severity of the instability, which is a judgement call. Imbrication of the tendon of the subscap- ularis muscle alone may best be suited for mild degrees of shoulder instability, where the tendon is intact and the medial joint capsule is only mildly stretched (5). Initially, the former established method was supposed to perform in this case.
Transposition of the biceps tendon will provide permanent Fig 2. Preoperative (A) and postoperative (B) ventrodorsal radiographic views of left medial shoulder joint luxation.
Fig 1. Intra-operative photographs of the dog. Transverse humeral retinaculum was incised and the tendon of the biceps brachii muscle was exposed (A). The tendon of the biceps brachii muscle was relocated between two cancellous bone screws. The figure of eight suture method using polyamide suture was performed over the tendon (B).
100 Ho-Hyun Lee, Sung-Ho Yun, Kwang-Ho Jang and Young-Sam Kwon
support to the luxated shoulder in cases of either lateral or medial luxation (8). However, we have no choice but to use the modified method because the tendon of the biceps brachii muscle was too thin and short to insert a bone screw and spiked washer for reduction of medial luxation. The modi- fied technique used as follows; that the tendon of the biceps brachii muscle was placed between two cancellous bone screws on the proximal medial humerus and the figure of eight suture method using polyamide was sutured over the tendon to secure stably. This method may be useful for small or toy breed dog when it is difficult to apply spiked washer because of patient’s tiny size.
In this case, it is thought that chronic laxity of the shoul- der joint capsule and adjacent ligaments may result in medial luxation because of continuous going up and down the bed. It is considered that the two cancellous bone screws and the figure of eight suture method have successfully returned the humeral head in the glenoid cavity. In conclusion, this case report focuses on the modified surgical technique to correct medial shoulder luxation when it is difficult to transpose the tendon of the biceps brachii muscle using bone screw and spiked washer in small or toy breed dogs.
References
1. Craig E, Hohn RB, Anderson WD. Surgical stabilization of traumatic medial shoulder dislocation. J Am Anim Hosp Assoc 1980; 16: 93-102.
2. Hohn RB, Rosen H, Bohning RH, Brown SG. Surgical sta- bilization of recurrent shoulder luxation. Vet Clin North Am 1971; 1: 537-548.
3. Pettitt RA, Clements DN, Guilliard MJ. Stabilisation of medial shoulder instability by imbrication of the subscapularis muscle tendon of insertion. J Small Anim Pract 2007; 48:
626-631.
4. Puglisi TA. Canine humeral joint instability-part II. Compend Contin Educ Vet 1986; 8: 741-750.
5. Rochat MC. The shoulder. In: Veterinary surgery small animal volume 1, 1st ed. Missouri: Elsevier Saunders. 2012:
692-705.
6. Schulz KS. Diseases of the joints. In: Small animal surgery, 4th ed. Missouri: Mosby Elsevier. 2013: 1255-1261.
7. Talcott KW, Vasseur PB. Luxation of the scapulohumeral joint. In: Textbook of small animal surgery, 3rd ed. Phila- delphia: Elsevier Health Sciences. 2003: 1897-1904.
8. Wolff EF. Transposition of the biceps brachii tendon to repair luxation of the canine shoulder joint. Vet Med Small Anim Clin 1974; 1: 51-53.
개에서 상완이두건 변형 전위에 의한 내측 견관절 탈구의 안정화 증례
이호현*·윤성호*·장광호*·권영삼*,**1
*경북대학교 수의과대학, **경북대학교 줄기세포치료기술연구소
요 약 : 10살령의 2 kg의 암컷 치와와가 다리를 딛지 못하는 전지파행으로 내원하였다. 촉진시 대결절은 정상 위치 보 다 내측에서 촉진되었고 염발음이 간헐적으로 들렸다. 방사선학적 검사에서 좌측 내측 견갑상완 관절 탈구로 진단되 었다. 또한, 양측성으로 3기의 내측 슬개골 탈구도 관찰되었다. 외과적으로, 내측 견관절 탈구를 상완이두건 전위술로 정복하였다. 환견은 수술 6주째 정상 보행이었고 다리를 딛게 되었다.
주요어 : 견관절탈구, 대퇴이두건, 개
