Photograph of a congenital<unk>  menisci specimen from the University of Cape Town Pathology Learning Centre teaching collection. The Watanabe classification of<unk>  lateral<unk>  is: (A) Incomplete, (B) Complete, and C) Wrisberg-ligament variant Normally, the<unk>  is a thin crescent-shaped piece of cartilage that lies between the weight bearing joint surfaces of the femur and the tibia. It is attached to the lining of the knee joint along its periphery and serves to absorb about a third of the impact load that the joint cartilage surface sees and also provides some degree of stabilization for the knee. There are two menisci in the knee joint, with one on the outside (away from midline) being the lateral<unk>  and the inner one (towards midline) the medial<unk> . A<unk>  is a congenital anomaly of the knee found in 3% of the population (up to 15% in Asia). It typically affects the lateral<unk>  and may be found bilaterally (20%). Instead of the narrow crescent shape, as seen in a normal<unk>  above, a<unk>  is thickened, and has a fuller crescent shape. In addition, a<unk>  does not taper as much towards the center of the joint and is shaped like a disc. The thickness of the<unk> , its diminished vascular blood supply, and in some instances, weak capsular attachment, makes it more prone to tears compared to a normal<unk> . The anomaly in itself is asymptomatic; however, a tear of the<unk>  can result in pain, swelling, and snapping in the affected knee. The orthopedic classification of<unk>  menisci includes: complete, incomplete or Wrisberg-ligament types as depicted here. Coverage of the lateral tibial plateau determines the designation of complete or incomplete. The Wrisberg-ligament type has an abnormal posterior attachment by attaching to part of the posterior cruciate ligament.
Discoid meniscus
Meniscal cyst
Protrusio acetabuli
Calcaneal spur
Pes anserine bursitis
Luxating patella
Olecranon bursitis
Retrocalcaneal bursitis