1. The capsular changes in osteoarthritis of the hip and their pathogenesis are described, and it is concluded that symptoms are due mainly to this abnormality.
2. The clinical significance and pathogenesis of subchondral sclerosis, cysts, osteophytes, secondary subluxation and new bone formation on the lower border of the femoral neck are discussed.
3. These bony features which can be seen in the radiograph may, under certain circumstances, be correlated with the symptoms.
4. The influence of joint debris and capsular fibrosis upon the symptoms arising in other osteoarthritic joints is considered.
5. The mechanism by which osteoarthritis develops in hip joints with an anatomical abnormality is discussed in relation to the normal functional anatomy of the hip.
6. The evolution of osteoarthritis in dysplasia of the hip is considered with special reference to its diagnosis, prognosis and early treatment.
7. The supposition that osteoarthritis is commonly due to progressive ischaemia in the femoral head has been investigated and is rejected.
8. The cause of idiopathic osteoarthritis remains obscure but the evidence suggests that constitutional rather than local conditions in the joint account for many of these cases.