Impairment of the collagenase-3 endocytotic receptor system in cells from patients with osteoarthritis.

Objective: Collagenase-3, a matrix metalloproteinase (MMP-13) that can degrade collagen II and aggrecan, is produced by osteoarthritic (OA) chondrocytes and may contribute to matrix destruction in this disease. Our laboratory has previously identified a specific endocytotic receptor for collagenase-3 on osteoblastic and fibroblastic cells, which couples with the low-density lipoprotein receptor-related protein (LRP1) to mediate the internalization and degradation of this enzyme. We hypothesized that the activity of this receptor system is reduced in OA chondrocytes which may lead to increased local extracellular levels of collagenase-3 and increased destruction of the cartilage matrix at pericellular sites.

An inexpensive alternative approach to bone compression analyses.

A new method for testing the compression strength of vertebrae was developed and implemented using minimal resources and time expenditure. The device digitally measured and analyzed the torque and force necessary to load rat lumbar and thoracic vertebrae to failure. The system was calibrated using a series of known lead masses.

Neurological complications resulting from supracondylar fractures of the humerus in children.

One hundred thirty-eight children with supracondylar fractures of the humerus were reviewed. Seventeen (12%) exhibited neurological deficits. Nine median, four ulnar, and four radial neuropathies were encountered.

Antibiotics delivered by an implantable drug pump. A new application for treating osteomyelitis.

Osteomyelitis is usually treated with wide surgical debridement and prolonged intravenous antibiotics. The advent of the implantable drug pump has led us to evaluate this therapeutic modality for the treatment of osteomyelitis. We have previously shown that amikacin retains microbiologic activity in an implantable drug pump over a six-week period when incubated at 37 degrees C.

Isolated avulsion of the tibial origin of the anterior tibiofibular ligament.

A case report of a patient with an isolated avulsion of the anterior tubercle of the tibia is presented. This is the origin of anterior tibiofibular ligament, and this injury is the first stage of a supination external rotation injury of the ankle. It can be easily missed and, if not treated properly, can result in an unstable ankle.