Take a look at the images from an MRI case from our case files. Compare your thoughts with the findings from our expert VET.CT radiologist, which are set out below in the full case report.
A five and a half year old FN Miniature Dachshund presented with chronic left forelimb lameness over 6 months duration. Left shoulder arthroscopy performed 4 months ago revealed moderate inflammation.
Clinical History:
PLEASE NOTE THE MARKER HAS BEEN PLACED ON THE RIGHT SHOULDER, AND IMAGES OF THE RIGHT
SHOULDER HAVE BEEN INCLUDED FOR COMPARISON.
Chronic left forelimb lameness for greater than 6 months duration. Left shoulder arthroscopy performed in 4 months ago which showed moderate inflammation observed. An intra-articular of steroids was administered
at that time. There has been no resolution of lameness and she is repeatably painful on biceps test on examination.
Anatomic regions: Shoulder
Details of study and technical comments: An MRI of the shoulders including the sequences mentioned above is available for interpretation. The study is of good diagnostic quality.
Diagnostic interpretation:
LEFT SHOULDER:
The bicipital tendon has mild central T1 hyperintensity and is increased in cross-sectional area (yellow circle). The medial glenohumeral ligament is increased in volume, irregular in shape and mildly heterogeneous in T2
signal (thin yellow arrows).
picture
Mild irregular remodelling is present on the caudal margin of the humeral head; this is best observed in the PD fat sat images. Increased fluid signal distends the joint capsule (thin orange arrows). Increased volume is
present in the myotendinous region of the supraspinatus (orange arrowheads). Within the myotendinous region of the supraspinatus, there is a focal fluid signal (blue circle). The increased volume creates an
undulating margin along the increased fluid signal within the bicipital tendon sheath (thin blue arrows).
Irregular soft tissue fluid interface is present in the bicipital tendon sheath (blue arrowhead). In the transverse plane, the mildly increased volume of the supraspinatus (yellow arrowheads) reduces the cranial volume of the bicipital tendon sheath (thin white arrows). There is marked enhancement of the distal infraspinatus (pink free-form lines). Subtle heterogenous enhancement is observed within the joint space and near the bicipital tendon sheath (green arrowheads).
picture
RIGHT SHOULDER: No abnormalities are detected in the articular margins of the scapula and humerus, intracapsular fluid volume, and periarticular structures. The caudal circumflex humeral artery is well defined. The included structures of the elbows bilaterally and cervical spine are unremarkable.
Conclusions:
The changes of the left shoulder are multi-dimensional and implicate the medial stabilising structures (medial glenohumeral ligament), the cranial stabilising structures (supraspinatus and bicipital tendon) as well as a lateral stabilising force (the infraspinatus). Additionally, there are indications of ongoing inflammatory changes such as fibrillation and synovitis which may contribute to persistent intra-articular remodelling. Overt bone sclerosis is not recognised.
Literature: Murphy, S. E., Ballegeer, E. A., Forrest, L. J., & Schaefer, S. L. (2008). Magnetic resonance imaging findings in dogs with confirmed shoulder pathology. Veterinary Surgery, 37(7), 631-638.