Calcium crystals and cartilage damage.

Recent advances in understanding the pathogenesis and mechanisms whereby calcium crystals contribute to cartilage damage are highlighted in this review. Studies that help elucidate pathologic crystal formation in cartilage are discussed. The effect of calcium pyrophosphate dihydrate crystals on the progression of joint degeneration in vivo is noted. Early-onset osteoarthritis and chondrocalcinosis are linked to chromosome 8q. A syndrome of chondrocalcinosis associated with recurrent childhood seizures is linked to chromosome 5p. An unusual destructive and hypertrophic arthropathy of the atlantoaxial joint in calcium pyrophosphate dihydrate crystal deposition disease is described.