Restoring Cartilage: The Holy Grail of Orthopaedics.

Abstract

Theoretically, articular cartilage restoration should be a solvable biological/mechanical problem. But repairing, restoring, or replacing hyaline cartilage and the matrix that supports it presents formidable physiological and physical challenges. For decades, researchers have been investigating many different methods of cartilage repair, and no approach has yet risen to “gold standard” status. As the “Current Concepts Review” in the February 19, 2014, edition of JBJS points out, the main strategy for cartilage “self-repair” is bone marrow stimulation, primarily via microfracture. Restorative/replacement approaches focus on cartilaginous constructs composed of allogenic, autogenic, or tissue-engineered materials. This month’s “Case Connections” looks at four cases involving three different restorative/replacement approaches to cartilage defects. The variable outcomes emphasize the gaps between theoretical and clinical solutions to this common skeletal problem. In the June 24, 2015, edition of JBJS Case Connector, Ramirez et al. report on a high-school quarterback whose full-thickness glenoid osteochondral defect was filled arthroscopically with particulated juvenile cartilage allograft. The sixteen-year-old football player presented with a two-month history of right shoulder pain and a feeling of instability, precipitated by a tackle during a football game. Physical exam revealed forward shoulder elevation to 150° with moderate pain but no muscle atrophy. External rotation was 60°, and the shoulder rotated internally to the T7 vertebral level with pain and crepitus. Anterior apprehension, relocation, and load-shift tests were all positive. Radiographs showed a 2 × 2-cm lucency in the inferior-central region of the glenoid. MRI showed an anterior-inferior labral tear and an osteochondral glenoid defect that measured 1.7 × 2.5 cm. After a period of unsuccessful nonoperative management, diagnostic arthroscopy revealed a displaced anterior-inferior labrum and a full-thickness, 1.5 × 1.5-cm cartilage defect of the inferior-central region of the glenoid. Surgeons repaired the labrum arthroscopically and then dried the surface of the defect by …