Prevalence of Computed Tomographic Subchondral Bone Lesions in the Scapulohumeral Joint of 32 Immature Dogs With Thoracic Limb Lameness

Abstract

Osteochondrosis is a common developmental abnormality affecting the subchondral bone of immature, large breed dogs. The purpose of this retrospective study was to describe CT lesions detected in scapulohumeral joints of 32 immature dogs undergoing CT for thoracic limb lameness. Eight dogs (14 scapulohumeral joints) had arthroscopy following imaging. Thirteen dogs (19 scapulohumeral joints) were found to have CT lesions, including 10 dogs (16 scapulohumeral joints) with subchondral bone lesions and 3 dogs with enthesopathy of the supraspinatus tendon. In one dog, subchondral bone lesions appeared as large oval defects within the mid-aspect of the glenoid cavities, bilaterally. These lesions resembled osseous cyst-like lesions commonly identified in the horse. This is the first report of such a presentation of a subchondral bone lesion in the glenoid cavity of a dog. In all dogs, small, focal, round or linear lucent defects were visible within the cortical bone at the junction of the greater tubercle and intertubercular groove. These structures were thought to represent vascular channels. Findings from this study support the use of CT as an adjunct modality for the identification and characterization of scapulohumeral subchondral bone lesions in immature dogs with thoracic limb lameness.

Computed tomographic arthrography is a useful adjunct to survey computed tomography and arthroscopic evaluation of the canine shoulder joint

“…Out of 13 arthroscopically confirmed lesions, CT and computed tomography arthrography failed to detect two subchondral bone lesions identified by arthroscopy, however detected three other subchondral bone lesions, which were not identified by arthroscopy. A previous study found that arthroscopy identified only 64% of osteochondral lesions identified on CT examination of canine scapulohumeral joints . Arthroscopic evaluation is limited to surface defects and may fail to detect lesions in deeper structures .…”

“…Although used as the reference standard for the purposes of this study, arthroscopy has been shown to miss valid lesions that are identified by CT, particularly those located in the joint periphery or deep to the synovial lining . In the current study, only intraarticular structures were assessed in order to minimize this bias.…”

“…Determining the exact cause of shoulder lameness is often challenging, and various imaging techniques have been described . Principal pathologies include bicipital tenosynovitis, biceps brachii tendon rupture, bicipital mineralizing tendinopathy, subscapularis tendon rupture, medial and lateral glenohumeral ligament rupture, osteochondrosis, osteochondrosis dissecans of the humeral head and intertubercular groove joint mice, fractures, luxations, arthritis, and neoplasia . Arthroscopy has been advocated as the ‘gold standard’ for assessment of intraarticular structures of the canine shoulder …”

“…Computed tomography (CT) is frequently used in the diagnosis of shoulder lameness, however, its inherently limited soft tissue contrast resolution restricts its diagnostic ability for intraarticular structures. The use of contrast medium introduced into the joint cavity overcomes this limitation, by delineating the margins of the synovial and cartilaginous structures.…”

Detection of fragment migration into the biceps tendon sheath originating from a humeral osteochondrosis lesion – A case report and review of the literature

“…However, besides accurate assessment of site and extent of the lesion, cartilage, and subchondral bone changes, the detection of mineralized and non-mineralized loose bodies and the assessment of the biceps tendon and tendon sheath are mandatory for a detailed diagnosis, accurate prognosis, and adequate treatment. The use of more sensitive imaging modalities such as computed tomography (CT; [5,[11][12][13]), ultrasonography (US; [8,[14][15][16], and arthroscopy [17,18] aid in complete evaluation of the shoulder joint and should be discussed below. This case report describes the presence of a migrated osteochondral fragment in the biceps tendon sheath as a sequela to osteochondrosis dissecans of the caudal humeral head in a medium-sized dog.…”