Joint pain.

An unpleasant sensation characterized by physical discomfort (such as pricking, throbbing, or aching) localized to the knee.

An abnormality of the knee joint or surrounding structures.

Joint pain affecting the hip.

A rare group of primary bone dysplasia disorders characterized by the association of epiphyseal anomalies of long bones causing joint pain early in life, recurrent osteochondritis and early arthrosis. This group contains an heterogeneous group of diseases with variable expression. Common reported clinical signs include waddling gait and pain at onset, and moderate short stature. Some forms are mainly limited to the femoral epiphyses, while several other syndromes are characterized by the association of multiple epiphyseal dysplasia with other clinical manifestations such as myopia, deafness and facial dysmorphism. Diagnosis relies on identification of the radiological features.

Osteoarthritis (OA) is a degenerative disease of the joints characterized by degradation of the hyaline articular cartilage and remodeling of the subchondral bone with sclerosis (Meulenbelt et al., 2006). Clinical problems include pain and joint stiffness often leading to significant disability and joint replacement. Osteoarthritis exhibits a clear predilection for specific joints; it appears most commonly in the hip and knee joints and lumbar and cervical spine, as well as in the distal interphalangeal and the first carpometacarpal (base of thumb) and proximal interphalangeal joints of the hand; however, patients with osteoarthritis may have 1, a few, or all of these sites affected (Stefansson et al., 2003). According to a conservative estimate, greater than 70% of the population of the United States at age 65 years is affected by the disease, reflecting its age dependence. Genetic Heterogeneity of Susceptibility to Osteoarthritis Susceptibility to osteoarthritis has been associated with variation in other genes: OS2 (140600) with variation in the MATN3 gene (602109) on chromosome 2p24; OS3 (607850) with variation in the ASPN gene (608135) on chromosome 9q22; and OS5 (612400) with variation in the GDF5 gene (601146) on chromosome 20q11. Other susceptibility loci for osteoarthritis have been mapped to chromosomes 2q33 (OS4; 610839) and 3p24 (OS6; 612401).

The presence of abnormal calcium deposition of the intervertebral disk.

A Schmorl's node is the herniation of nucleus pulposus through the cartilaginous and bony end plate into the body of the adjacent vertebra.

An irregular surface of the vertebral end plates, which are normally relatively smooth.

An abnormal flattening of the proximal epiphysis of the femur.

An alteration of the normally smooth contour of the epiphysis leading to an irregular appearance.

Reduction in the size or volume of epiphyses.

An abnormal flattening of the distal epiphysis of femur.

Anomaly of the contour of the Distal epiphysis of femur such that its normally smooth appearance is irregular.