It is probable that both genetic and environmental factors play some part in the aetiology of most cases of degenerative hip disease. Geneticists have identified some single gene disorders of the hip, but have had difficulty in identifying the genetics of many of the common causes of degenerative hip disease. The heterogeneity of the phenotypes studied is part of the problem. A detailed classification of phenotypes is proposed. This study is based on careful documentation of 2003 consecutive total hip replacements performed by a single surgeon between 1972 and 2000. The concept that developmental problems may initiate degenerative hip disease is supported. The influences of gender, age and body mass index are outlined. Biomechanical explanations for some of the radiological appearances encountered are suggested. The body weight lever, which is larger than the abductor lever, causes the abductor power to be more important than body weight. The possibility that a deficiency in joint lubrication is a cause of degenerative hip disease is discussed. Identifying the phenotypes may help geneticists to identify genes responsible for degenerative hip disease, and eventually lead to a definitive classification.
- Degenerative hip disease
- radiological and pathological classification
- genetic and environmental factors
- hip biomechanics
- socket wear
- femoral head migration
- influence of gender
- age and bmi.
We wish to express our gratitude to Dr R. Davey, Toronto, Ontario, and Dr R. Bourne, London, Ontario, who reviewed the manuscript and helped with constructive suggestions, and to Mr B. Weaver, Northern Ontario School of Medicine, Human Sciences Division, Thunder Bay, Ontario, for his statistical assistance.
No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.
- Received December 22, 2011.
- Accepted April 24, 2012.
- ©2012 British Editorial Society of Bone and Joint Surgery