Osteoarthritis is extremely common and many different causes for it have been described. One such cause is abnormal morphology of the affected joint, the hip being a good example of this. For those joints with femoroacetabular impingement (FAI) or developmental dysplasia of the hip (DDH), a link with subsequent osteoarthritis seems clear. However, far from being abnormal, these variants may be explained by evolution, certainly so for FAI, and may actually be normal rather than representing deformity or disease. The animal equivalent of FAI is coxa recta, commonly found in species that run and jump. It is rarely found in animals that climb and swim. In contrast are the animals with coxa rotunda, a perfectly spherical femoral head, and more in keeping with the coxa profunda of mankind. This article describes the evolutionary process of the human hip and its link to FAI and DDH. Do we need to worry after all?

The August 2015 Children’s orthopaedics Roundup. 360 . looks at: Learning the Pavlik; MRI and patellar instability; Cerebral palsy and hip dysplasia; ‘Pick your poison’: elastic nailing under the spotlight; Club feet and surgery; Donor site morbidity in vascularised fibular grafting; Cartilage biochemistry with hip dysplasia; SUFE and hip decompression: a good option?

The April 2015 Children’s orthopaedics Roundup³⁶⁰ looks at: Reducing the incidence of DDH – is ‘back carrying’ the answer?; Surgical approach and AVN may not be linked in DDH; First year routine radiographic follow up for scoliosis not necessary; Diagnosis of osteochondritis dessicans; Telemedicine in paediatrics; Regional anesthesia in supracondylar fractures?