Arthroscopic Biceps Brachii Tenotomy as a Treatment for Canine Bicipital Tenosynovitis
Five dogs of varying breeds, ranging from 4 to 8 years in age, were presented with clinical signs consistent with bicipital tenosynovitis. After failure of conservative treatment, each dog underwent shoulder arthroscopy. Following examination of the scapular humeral joint, the bicipital tendon was severed with a bipolar radiofrequency electrosurgical system. The arthroscopic procedure resulted in a good to excellent outcome for all five dogs.
Introduction
Bicipital tenosynovitis is a disease process in which inflammation occurs in the tendon origin of the biceps brachii and surrounding synovial sheath. This inflammatory process has been associated with tendon strain, trauma, partial tendon rupture, or joint mice entrapment in the bicipital tendon sheath.1 This disease process is not unique to the dog,1–8 as it also affects horses9 and humans.10–13
The clinical signs are variable but usually include a chronic intermittent or progressive forelimb lameness, which worsens with exercise. The dog is typically able to bear weight on the affected limb; however, pain may be elicited by flexing the shoulder and extending the elbow while applying pressure to the tendon in the intertubercular groove.2 Radiographs, ultrasound, arthrography, and shoulder arthroscopy are useful to help in the diagnosis of bicipital tenosynovitis. These imaging techniques can show degenerative joint disease, filling defects in the tendon sheath, mineralization within the tendon, tendonitis, and partial or complete tendon ruptures.3–5 Subtle, recurrent, weight-bearing lameness of the forelimb in the dog can be the result of other orthopedic or neurological problems. These may include sesamoid fractures, chronic low-grade carpal or cubital degenerative joint disease, mineralization of the supraspinatus tendon, and other orthopedic conditions of the forelimb. Nerve-root tumors or partial internalization of a disk may produce intermittent weight-bearing lameness of the forelimb as a root signature.
The origin of the biceps brachii tendon is the supraglenoid tubercle. The tendon passes across the glenohumeral joint space and through the intertubercular groove of the humerus where it is held in place by the transverse humeral ligament. The surrounding synovial sheath is an extension of the glenohumeral joint capsule which surrounds the tendon just distally to the transverse humeral ligament.14
Injury to the biceps brachii tendon has been associated with joint mice entrapment, direct or indirect trauma, partial tendon rupture, or rupture of the transverse intertubercular ligament.13 In one study, five of 17 dogs had a history of shoulder trauma prior to the onset of lameness.15 Once injury to the tendon or surrounding synovial membranes occurs, the inflammatory changes begin. Continual movement of these inflamed tissues in the intertubercular groove causes pain and additional inflammation.1 Cellular infiltration, in response to the inflammation, causes adhesions between the synovial sheath and the tendon. Additionally, hypoxia occurs, which allows for a transformation of the cellular structure of the tendon into fibrocartilage and subsequent chondrocyte-mediated mineralization.167
The goal of treatment is to reduce the movement of the inflammatory tissues across the intertubercular groove.1 If the injury is acute and the pathological changes are reversible, a one- or two-dose course of an aseptic, intra-articular injection of a long-acting corticosteroid, followed initially by strict rest with a gradual return to activity, may allow for resolution.2 Surgical treatment is recommended for cases in which a mechanical problem is found initially or for those that do not respond to medical therapy. Traditionally, surgical treatment involves a tenodesis of the biceps brachii tendon to the proximal portion of the humerus. Typically, this surgery has a good prognosis.2 Noted surgical complications with the tenodesis include implant migration, delayed union of the osteotomy, and seroma formation.6
The goals of these case studies are to show that arthroscopic biceps brachii tenotomy is a viable option for treating bicipital tenosynovitis in canines, and that a prospective study is warranted to statistically compare the morbidity of traditional surgical tenodesis techniques to the arthroscopic tenotomy.
Materials and Methods
Based on physical examination findings and imaging studies, the diagnosis of bicipital tenosynovitis was made. If there was not a clinical response to medical therapy, the patient was considered a surgical candidate. Once a dog was considered a surgical candidate, preanesthetic blood work was done that included a complete blood count and a serum biochemical profile. The preanesthetic protocol included glycopryolate (0.01 mg/kg body weight, intramuscularly [IM]), acepromazine (0.02 mg/kg body weight, IM), and morphine (1.0 mg/kg body weight, IM), while anesthesia was induced with propofol (4.0 to 6.0 mg/kg body weight, intravenously [IV] slowly to effect) and maintained with isoflurane. Lactated Ringer’s solution was administered IV at 10.0 mL per kg body weight per hour during anesthesia.
The appropriate shoulder was clipped and surgically prepared. A 2.7-mm arthroscopea was introduced through a trocar in the standard arthroscopic portal (about 1-cm distal and 2-cm caudal to the acromion process between the two heads of the deltoid muscle).16 Chilled lactated Ringer’s solution was infused into the joint space with a fluid pump to allow visualization, while egress flow was maintained through a 2.9-mm instrument canula,b and introduced into the joint just cranial to the infraspinatus tendon. A thorough arthroscopic examination of the scapulohumeral joint was conducted. After joint and bicipital tendon evaluation, the bicipital tendon was again visualized, and a bipolar radiofrequency electrosurgical systemc was placed into the joint through the 2.9-mm instrument canula and was used to transect the bicipital tendon near its origin [Figures 1–3]. The bipolar radiofrequency electrosurgical system, instrument canula, and scope were then removed, and 1.0 mL of bupivacained was injected into the joint. The skin incisions were closed with 4–0 nylone with simple interrupted sutures. Home care instructions included 10- to 15-minute walks three to four times a day, ice packs for 5 to 10 minutes twice daily, and no jumping, running, or off-leash activity for 2 weeks. Additional exercise and leash activity varied with each individual case.
All dogs were reevaluated at 2 weeks for suture removal. Gait evaluation at that time included a walk and assessment of the surgical site. More extensive follow-up evaluations were done on a recurrent basis, approximately 2 and 6 months following surgery. The dog’s gait was evaluated at both a walk and a trot, and shoulder range of motion was evaluated and compared to the nonsurgical limb. Pain was also assessed with bicipital groove palpation, biceps brachii palpation, and shoulder movement, and was compared to the nonsurgical limb. The owner was also questioned in regard to the dog’s current activity level and any use of non-steroidal anti-inflammatory drugs. These results were placed into an objective rating scale developed by Stobie, Wallace, Lipowitz, King, and Lund,6 and were assigned a rating of excellent, good, fair, or poor. Definitions for this rating scale are as follows: “excellent” has a normal gait, limb function, and range of motion, with no signs of pain during palpation of affected tendon or manipulation of the affected joint; “good” has normal gait, limb function, and range of motion, with signs of mild pain during palpation of the affected tendon or manipulation of the affected joint; “fair” has a mild lameness, but improved when compared with condition prior to surgery, with signs of pain on palpation of affected tendon and manipulation of the affected joint; “poor” has a marked lameness that was more severe than before surgery, poor range of motion in affected joint, and signs of pain during palpation of affected tendon and manipulation of affected joint.
Case Reports
Case No. 1
A 4-year-old, 35-kg, intact male Labrador retriever presented for a right forelimb lameness. Physical examination revealed pain response on right bicipital tendon palpation and shoulder manipulation, as well as decreased range of motion of both elbows. Radiographic findings of the right shoulder joint included a large, round fragment in the soft tissue cranial to the bicipital groove and smooth mineralization present adjacent to the fragment. Smooth mineralization was also present in the bicipital groove. The left shoulder joint had roughening of the bicipital groove. Both the right and left elbows had osteophytes present on the anconeal process and the proximal cranial radial head. Initial treatment included an aseptic intra-articular injection of 1.0 mg triamcinolone acetonidef in the right shoulder, followed by strict exercise restriction. The left shoulder was not treated, as there were no clinical signs of pain or lameness. Initially, the dog did well with a gradual return to function, but he was presented 4 months later with a recurrence of the right forelimb lameness.
Physical examination revealed that the lameness was worsened by flexing the shoulder or following digital pressure on the proximal aspects of the tendon. There was pain on right bicipital tendon palpation and shoulder manipulation, as well as a decreased range of motion of both elbows. Surgery was recommended, and an arthroscopic bicipital tenotomy was performed.
At suture removal 2 weeks following surgery, the dog had a normal walk. Three months later upon reexamination, the dog had no lameness at a walk or trot, shoulder range of motion was normal, and no pain was associated with bicipital groove palpation and biceps brachii palpation; however, a slight pain response was present with shoulder manipulation. Six months following surgery, the dog still had no lameness at a walk or trot, shoulder range of motion remained normal, no pain was present on bicipital groove palpation and biceps brachii palpation, and there was no pain response present with shoulder manipulation. The overall outcome was rated as excellent [see Table].
Case No. 2
An 8-year-old, 38-kg, neutered male Labrador retriever was presented for a right forelimb lameness. Physical examination findings included a toe-touching lameness, with pain on shoulder flexion. Radiographic findings of the right shoulder included mineralization near the greater tubercle, smooth mineralization present in the bicipital groove, and a roughened acromion process. Joint fluid analysis showed no signs of infection. Initial treatment included an aseptic intra-articular injection of 1.0 mg triamcinolone acetonidef in the right shoulder, followed by strict exercise restriction. The dog did not respond well to glucocorticoid therapy and remained lame.
Four weeks later, an arthroscopic tenotomy of the bicipital tendon was performed. At suture removal 2 weeks following surgery, the dog had no lameness at a walk. Four months later upon examination, the dog had no lameness at a walk, a slight lameness at a trot, normal range of motion in the shoulder, no pain upon bicipital groove palpation and biceps brachii palpation, but a slight pain response with shoulder manipulation. Six months following surgery, examination revealed no pain upon right shoulder manipulation, bicipital groove palpation, and biceps brachii palpation. There was no lameness at a walk or trot. However, the owner reported that there was a slight intermittent lameness that seemed to occur after increased activity. The overall outcome was rated as good, due to the owner’s report of the intermittent lameness [see Table].
Case No. 3
A 7-year-old, 27-kg, spayed female German shorthaired pointer was presented for a left forelimb lameness. Physical examination findings included a toe-touching lameness, with pain on shoulder flexion and extension. Radiographic findings of the left shoulder revealed sclerosis and roughening of the bicipital groove. Initial treatment included an aseptic intra-articular injection of 1.0 mg triamcinolone acetonidef in the left shoulder, followed by strict exercise restriction. The dog did not respond well to glucocorticoid therapy and remained lame.
One week later, an arthroscopic tenotomy of the bicipital tendon was performed with the previously described technique, with the addition that a biopsy of the surrounding synovium was taken during the procedure because a considerable amount of synovitis was present. Histopathology results were described as reactive fibrosis with hemosiderin deposition, with no evidence of septic-type lesions or neoplasia. At suture removal 2 weeks postoperatively, the dog had no lameness at a walk. Two months later upon reexamination, the dog had no lameness at a walk or trot, normal range of motion in the shoulder, and no pain present on bicipital groove and biceps brachii palpation or shoulder manipulation. Follow-up examination 6 months after surgery revealed no lameness at a walk or trot. No pain was associated with bicipital groove and biceps brachii palpation. Shoulder range of motion remained normal and pain free. The overall outcome was rated as excellent [see Table].
Case No. 4
A 5-year-old, 34-kg, neutered male mixed-breed dog was presented for a left forelimb lameness after exercise. Physical examination findings included an intermittent, left fore-limb weight-bearing lameness, with pain on both right and left bicipital tendon palpation. Radiographic findings of the right and left shoulders showed no abnormalities. Ultrasound examination of the right biceps tendon showed no abnormalities, whereas the left biceps tendon had a focal, crescent-shaped, hyperechoic region in the tendon approximately 2 cm from the origin of the scapula. Initial treatment included a tapering dose of carprofen with exercise restriction for 2 weeks. Upon reexamination 4 weeks later, the dog showed improvement but still had a mild, left forelimb, intermittent weight-bearing lameness, with pain of the left bicipital tendon upon palpation. Additional radiographs of the left shoulder showed no abnormalities, but ultrasound reexamination showed multiple hyperechoic foci in the biceps tendon 2 to 3 cm distal to its origin.
Two weeks later, an arthroscopic tenotomy of the left bicipital tendon was performed using the previously described technique. At suture removal 2 weeks postoperatively, the dog had no lameness at a walk and was reported by the owner to be “running around like a puppy.” Four weeks postoperatively, the dog had a mild intermittent lameness and was found to experience pain over the biceps groove and proximal portion of the biceps brachii. Consequently, 4 additional weeks of continued rest and a course of carprofen was recommended. At 8 weeks postoperatively, reexamination revealed a slight intermittent lameness at a walk, persistent lameness at a trot, normal range of motion in the shoulder, no pain on bicipital groove and biceps brachii palpation, but a pain response upon left shoulder manipulation. Further recommended care included continued rest with only minimal activity, followed by a very gradual progression to moderate activity. Seven months following surgery, reexamination revealed that the dog had no lameness at a walk or trot, normal range of motion in the shoulder, and no pain on bicipital groove and biceps brachii palpation or shoulder manipulation. The dog was no longer on carprofen or other pain medications. Consequently, the outcome at that time was rated as excellent [see Table].
Case No. 5
A 7-year-old, 37-kg, neutered male golden retriever was presented for an intermittent, right forelimb lameness. Physical examination revealed pain on both right and left bicipital tendon palpation, although the right bicipital tendon was significantly more painful than the left. Radiographic findings of both shoulders showed mild roughening in both bicipital grooves. An aseptic, intra-articular injection of 1.0 mg triamcinolone acetonide was given in the right shoulder, followed by strict exercise restriction for 4 weeks, at which time the right shoulder lameness was as pronounced as prior to glucocorticoid therapy.
One week later, an arthroscopic tenotomy of the right bicipital tendon was performed using the previously described technique. At suture removal 2 weeks postoperatively, the dog had no lameness on the right limb and a slight lameness on the left. Two additional weeks of exercise restriction were maintained, and upon follow-up examination 4 weeks postoperatively, the dog had no lameness on the right or left limb. Leash activity was limited for 2 additional weeks, then a gradual return to former activity level was allowed. Eight weeks postoperatively, the dog was again going on long walks and playing “fetch” with no lameness reported by the owner. Physical examination revealed no lameness at a walk or trot, a normal range of motion for both limbs, and no pain present on bicipital groove and biceps brachii palpation or shoulder manipulation bilaterally. Six months following surgery, there was no lameness present at a walk or trot. Palpation of the right bicipital groove and biceps brachii muscle revealed no pain, while shoulder range of motion remained normal and pain free. The overall outcome was rated as excellent [see Table].
Discussion
Bicipital tenosynovitis is a disease process in which surgery can improve the quality of life for patients that are unresponsive to medical therapy. In a conventional surgery, a tenodesis of the biceps brachii to the proximal portion of the humerus is performed.2 This procedure has good to excellent long-term results.6 However, there are several noted complications (besides the possibility of an infection) with conventional surgery, such as seroma formation, delayed healing of the osteotomy, and implant migration.6 The arthroscopic procedure described in this report simply transects the tendon, thereby ending the movement of the inflammatory tissues across the intertubercular groove. Use of the bipolar radiofrequency electrosurgical system easily transected the bicipital tendon; however, the use of an arthroscopic scalpel would be a suitable alternative for tendon transection. The authors suspect that over time the biceps brachii tendon forms adhesions to the proximal humerus and essentially produces a natural tenodesis. Scapulohumeral joint stability should be comparably equal to a traditional tenodesis. The benefits of this procedure include fewer postoperative complications, less tissue trauma, and subsequently less postoperative pain.
Although the case numbers are limiting, the clinical outcome with the arthroscopic procedure also has good to excellent long-term results. At the initial follow-up examination, only the gait was assessed. The authors were hesitant to perform a more thorough evaluation at that time, in order to not compromise the suspected adherence of the bicipital tendon to the proximal humerus. Two to 4 months following surgery, the results were varied; case nos. 3 and 5 had full function of the limb, while case nos. 1, 2, and 4 still had some form of lameness or pain for that time period. However, 6 to 7 months after the arthroscopic tenotomy, case nos. 1, 3, 4, and 5 had excellent outcomes, while case no. 2 had a good outcome due to the owner’s report of a slight, intermittent lameness after increased activity.
Bicipital tenosynovitis is not an isolated disease and is part of a generalized degenerative joint disease of the shoulder. Radiographic or ultrasonographic findings in the majority of these cases showed various degenerative changes, such as areas of hyperechocity, humeral and scapular osteophytes, bicipital groove changes, and in some cases mineralization of the tendon. In case no. 2, there was extensive radiographic evidence of scapulohumeral degenerative joint disease, which might explain the intermittent lameness in that dog.
It is also worth noting that case no. 4 had a recurrence of lameness during the recovery period. The authors believe that in the initial weeks following surgery, this dog was allowed too much activity before a stable adhesion had formed. This subsequently necessitated the dog to have a prolonged period of inactivity when compared to the other dogs. However, the dog improved with rest and a gradual return to increased activity. If the dog had not improved in response to the prolonged inactivity, a second procedure to establish a secure tenodesis, with either a bone screw and spiked washer or a bone tunneling technique, could have been attempted.2
The authors believe this is a novel and acceptable treatment for bicipital tenosynovitis and know of no other species where such surgery has been performed. A comparable medical condition exists in humans, when the tendon of the long head of the biceps brachii ruptures. Current therapy in humans with this condition is variable and dependent on other concurrent shoulder pathology.10 Surgical versus nonsurgical treatment for this condition is a subjective decision dependent on the age of the patient and strength needed in the affected arm.11 Without surgery, the results in humans are variable; however, consistent findings include less strength in elbow flexion and forearm supination and variable cosmetic concern about altered upper-arm appearance.11–13 Comparatively, in these five cases, no manifestation of decreased elbow function was noticed postoperatively; the authors believe the brachialis muscle maintains normal elbow flexion while the biceps tendon is healing. Based on clinical findings, the authors believe the healing that occurs after the arthroscopic biceps brachii tenotomy is performed is similar to what has been observed in humans when nonsurgical treatment of a ruptured biceps brachii tendon is elected.
Variables in this report include presurgical case management, owner compliance to postoperative recommendations, and length of time to recovery. These variables interrelate and may have affected each case individually. Also, the end effect of the tenotomy is unknown. However, the overall clinical result was that each case markedly improved when compared to the presurgical condition, and the improvement was consistent with results from the standard tenodesis procedure as reported in the literature.6
The limited number of cases in this report does not support statistical analysis; however, the authors feel that this technique warrants further study as an acceptable treatment for bicipital tenosynovitis. Due to the relatively few cases of bicipital tenosynovitis and the increasing use of arthroscopy, the authors believe that a well-designed, multi-institutional, prospective study is warranted.
Conclusion
The use of the arthroscopic biceps brachii tenotomy appears to be an effective method to treat bicipital tenosynovitis when medical therapy is unrewarding. The clear benefits of the arthroscopic procedure are the reduced risks of postoperative complications as well as only a minimal amount of postoperative pain, when compared to traditional biceps brachii tenodesis. Although this report contains a limited number of cases, all five cases resulted with normal scapulohumeral range of motion and improved use of the affected limb. These results were consistent with a traditional tenodesis procedure. Consequently, the authors believe that a prospective study used to statistically compare the traditional tenodesis with the arthroscopic tenotomy is warranted.
2.7-mm 30° Arthroscope; Smith and Nephew, Andover, MA
2.9-mm Cannula with flow port; Smith and Nephew, Andover, MA
VARP II; Mitek Products, Westwood, MA
Bupivacaine; Abbott Laboratories, Chicago, IL
Dermalon; Sherwood-Davis and Geck, Gosport, UK
Vetalog; Fort Dodge Animal Health, Fort Dodge, IA
Citation: Journal of the American Animal Hospital Association 38, 2; 10.5326/0380169
Citation: Journal of the American Animal Hospital Association 38, 2; 10.5326/0380169
Citation: Journal of the American Animal Hospital Association 38, 2; 10.5326/0380169
Arthroscopic image of the origin of the biceps brachii tendon prior to transection. Note the glenoid tubercle (open arrow), the biceps brachii tendon (closed arrow), and the surrounding inflamed synovium (open star).
Arthroscopic image of the beginning of the biceps brachii tenotomy (closed arrow), with the bipolar radiofrequency electrosurgical unit (closed star), near the glenoid tubercle (open arrow).
Arthroscopic image near completion of the biceps brachii tenotomy (closed arrows), with the bipolar radiofrequency electrosurgical unit (closed star), near the glenoid tubercle (open arrow).
