The management of full thickness articular cartilage defects is a challenging problem for orthopaedic surgeons. It has limited potential for healing and can be a significant source of pain and loss of function. Multiple cartilage repair strategies have been attempted. Matrix-induced Autologous Chondrocyte Implantation (MACI) has been shown to produce hyaline-like cartilage into chondral defects. The goal of this review is to provide the current principles and technique of the MACI procedure along with reported clinical outcomes with its use.

The goals of anterior cruciate ligament (ACL) reconstruction are to restore knee stability and function and to preserve joint health. Static tests for antero-posterior laxity (e.g. Lachman test or KT-1000 arthrometer) have typically shown restoration of normal or near-normal laxity with a variety of modern ACL reconstruction techniques. However, ACL reconstruction has failed to prevent early onset of osteoarthritis, and there is growing evidence that traditional single-bundle ACL reconstruction does not restore normal knee mechanics under functional loading conditions. ACL reconstruction may fail to restore normal rotational stability during the pivot shift. Abnormal internal-external rotation and ab/adduction have been reported after ACL reconstruction during normal daily activities like walking and running. Recently, cadaveric studies have shown the potential superiority of ACL double bundle (DB) reconstruction for restoring anatomy and mechanical function. However, clinical data demonstrating the clear superiority of DB reconstruction is lacking, due to the absence of well-controlled clinical studies. Additionally, dynamic knee function after anatomic DB ACL has yet to be assessed comprehensively.

We review historical and methodological approaches to measurements of intramuscular pressure (IMP) in humans. These techniques provide valuable measures of muscle tone and activity as well as diagnostic criteria for evaluation of exertional compartment syndrome. Although the wick and catheter techniques provide accurate measurements of IMP at rest, their value for exercise studies and diagnosis of exertional compartment syndrome is limited because of low frequency response and hydrostatic (static and inertial) pressure artifacts. Presently, most information on diagnosis of exertional compartment syndromes during dynamic exercise is available using the Myopress catheter. However, future research and clinical diagnosis using IMP can be optimized by the use of a miniature transducer-tipped catheter such as the Millar Mikro-tip.