Detection of intra-articular osteochondral bodies in the knee using computed arthrotomography

Complications of Rotator Cuff Surgery in Which Bioabsorbable Anchors Are Used

OBJECTIVE

This study assessed the utility of MRI in patients with new or persistent pain after surgery with bioabsorbable rotator cuff anchors. SUBJECTS AND METHODS. Three musculoskeletal radiologists prospectively reviewed MRIs of 30 patients with pain after rotator cuff repair with fixation by rotator cuff anchors. Each radiologist described the location of the rotator cuff anchors and whether the supraspinatus tendon was intact or not. MRI findings were correlated with second-look arthroscopy. Consensus MRI interpretations by the three radiologists were obtained retrospectively.

RESULTS

Of the 30 patients, nine had dislodgement of the rotator cuff anchors from the humeral head along with a full-thickness supraspinatus tendon retear. The dislodged rotator cuff anchor position could be determined on coronal and sagittal MRIs, providing the orthopedic surgeon a preoperative map for tendon reattachment and retrieval of the dislodged rotator cuff anchor. Four patients had loose rotator cuff anchors but intact supraspinatus tendons. Three patients had supraspinatus tendon retears, but the rotator cuff anchors were intact. In all 16 patients, arthroscopic findings confirmed MRI findings. Fourteen patients had intact rotator cuff anchors and intact supraspinatus tendons on MRI. Of these 14 patients, five had second-look arthroscopy confirming MRI findings.

CONCLUSION

MRI is useful in the assessment of patients with persistent or new-onset pain after supraspinatus tendon repair with rotator cuff anchors. MRI provides a presurgical map for second-look arthroscopy to assess retear of the supraspinatus tendon and also aids in retrieval of dislodged rotator cuff anchors.

Diagnostic imaging of lameness in small animals

The demand for advanced diagnostic imaging procedures such as nuclear scintigraphy, ultrasonography, computed tomography, and magnetic resonance imaging has increased dramatically over the past 10 years. Veterinarians, seeking to improve their diagnostic capabilities and clients willing to pursue "best medicine" have driven this demand, resulting in installation of advanced imaging facilities at most academic and private referral practices. Knowledge of potential benefits of various modalities will allow the veterinarian to optimize his or her use of diagnostic imaging in his or her own practice or in a referral practice.

Diagnostic imaging of osteochondrosis

This article includes imaging of the glenohumeral (shoulder), elbow, stifle, and tarsal joints. The imaging modalities discussed are survey radiography, contrast arthrography, linear tomography, ultrasound, computed tomography, scintigraphy and magnetic resonance. Survey radiography is the first choice imaging modality for diagnosing osteochondrosis dissecans in dogs. In cases where survey radiography fail to demonstrate a lesion other modalities such as scintigraphy, linear tomography, computed tomography, and magnetic resonance may be helpful. Survey radiography, contrast arthrography, computed tomography, and magnetic resonance may also provide additional information contributing to early diagnosis and treatment.

Injuries at the articulating surfaces of bone (chondral, osteochondral, subchondral fractures and osteochondrosis dissecans)

Fractures involving the articulating surfaces of bone are a common cause of joint disability. Management options are as numerous as the terms used to describe these lesions. These terms include osteochondral, transchondral, flake or chip fractures as well as osteochondrosis (osteochondritis) dissecans. The understanding of these traumatic lesions and their sequelae has been increased by modern imaging technology, especially magnetic resonance imaging (MRI). This paper reviews the mechanism of these injuries, their incidence, clinical presentation, radiological appearance and the principles of their treatment. Hyaline cartilage, subchondral bone plate and subchondral cancellous bone have to be seen as an anatomic unity. Subchondrally located cancellous microfractures, osteochondral fractures and solely chondral fractures are different manifestations of impaction injuries at the articulating surfaces. We believe that osteochondrosis dissecans in most cases is also the result of undiagnosed injury at the articulating surface of bone.