Chondral lesions of the hip and knee joints remain a challenging diagnostic and therapeutic problem. Magnetic resonance imaging technology remains the leading modality for noninvasive detection of articular pathology. Methods such as T2-weighted, T1rho-weighted, and delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) have progressed in their development from basic ex vivo work to active clinical studies, with protocols of these mapping methods available for some existing 1.5-Tesla (1.5-T) and/or 3-Tesla (3-T) magnetic resonance imaging technology. Emerging data are beginning to show how these parameters relate to the state of cartilage tissue, and instrument vendors anticipate including these protocols in their next-generation scanners. Semiautomatic segmentation methods are improving, but they remain one of the barriers to widespread utilization of magnetic resonance methods.
Attempts at surgical resurfacing of chondral lesions of the hip and knee have comprised both biologic and nonbiologic alternatives. Several technologies, such as microfracture, autologous chondrocyte implantation, and the osteochondral autograft transfer system (OATS), have provided short-term to midterm relief of pain and restoration of function. Proposed synthetic chondral substitutes continue to lack the durable mechanical properties of native tissue. Traditional arthroplasty remains the standard treatment for end-stage disease and has been associated with excellent clinical efficacy and survivability at ten years.
The United States regulatory environment for emerging cartilage treatment technologies relies on decisions by the U.S. Food and Drug Administration with input from the National Institutes of Health. Safety and efficacy are paramount concerns, with an additional focus on a product's claimed benefit and labeling. Optimal submissions for new cartilage treatment products provide regulators with sufficient information on the technology of the proposed device or therapy, complemented by thorough clinical, histological, and radiographic follow-up. 