In youth soccer players, cam deformities gradually develop during skeletal maturation and are probably stable from the time of growth plate closure. The formation of a cam deformity might be prevented by adjusting athletic activities during a small period of skeletal growth, which will have a major effect on the prevalence of hip osteoarthritis.

Cam-type deformities were recognizable and present from the age of 13 years and were more prevalent in soccer players than in their nonathletic peers. Cam-type deformity develops during adolescence and is likely to be influenced by high-impact sports practice.

Diagnostic performance of MR imaging of the knee is different according to lesion type and is influenced by various study design characteristics. Higher magnetic field strength modestly improves diagnostic performance, but a significant effect was demonstrated only for anterior cruciate ligament tears.

Objective signs to assess impairment in patients who are disabled by peripartum pelvic girdle pain hardly exist. The purpose of this study was to develop a clinical test to quantify and qualify disability in these patients. The study examined the relationship between impaired active straight leg raising (ASLR) and mobility of pelvic joints in patients with peripartum pelvic girdle pain, focusing on (1) the reduction of impairment of ASLR when the patient was wearing a pelvic belt, and (2) motions between the pubic bones measured by X-ray examination when the patient was standing on one leg, alternating left and right. Twenty-one non-pregnant patients with peripartum pelvic girdle pain in whom pain and impairment of ASLR were mainly located on one side were selected. ASLR was performed in the supine position, first without a pelvic belt and then with a belt. The influence of the belt on the ability to actively raise the leg was assessed by the patient. Mobility of the pelvic joints was radiographically visualized by means of the Chamberlain method. Assessment was blinded. Ability to perform ASLR was improved by a pelvic belt in 20 of the 21 patients (binomial two-tailed P = 0.0000). When the patient was standing on one leg, alternating the symptomatic side and the reference side, a significant difference between the two sides was observed with respect to the size of the radiographically visualized steps between the pubic bones (binomial two-tailed P = 0.01). The step at the symptomatic side was on average larger when the leg at that side was hanging down than when the patient was standing on the leg at that side. Impairment of ASLR correlates strongly with mobility of the pelvic joints in patients with peripartum pelvic girdle pain. The ASLR test could be a suitable instrument to quantify and qualify disability in diseases related to mobility of the pelvic joints. Further studies are needed to assess the relationship with clinical parameters, sensitivity, specificity and responsiveness in various categories of patients. In contrast with the opinion of Chamberlain, that a radiographically visualized step between the pubic bones is caused by cranial shift of the pubic bone at the side of the standing leg, it is concluded that the step is caused by caudal shift of the pubic bone at the side of the leg hanging down. The caudal shift is caused by an anterior rotation of the hip bone about a horizontal axis near the sacroiliac joint.

Radiographs of 20 plastinated human cadaveric lower legs were obtained in 12 positions of rotation to determine the optimal parameter for reliable assessment of syndesmotic and ankle integrity, and to assess the effect of positioning of the ankle on this parameter. Three observers measured eight parameters twice after four repetitions of ankle positioning. Intraclass correlation coefficients and reproducibility were assessed. Some tibiofibular overlap was present in all radiographs in any position of rotation. The medial clear space was smaller than or equal to the superior clear space in all radiographs. Intraclass correlation coefficients of the other parameters were too weak for reliable quantitative measurements, as was shown with a mixed model analysis of variance. This resulted from the inability to reproduce ankle positioning, even under optimal laboratory circumstances. This study shows that no optimal radiographic parameter exists to assess syndesmotic integrity. Tibiofibular overlap and medial and superior clear space are the most useful, because one-sided traumatic absence of tibiofibular overlap may be an indication of syndesmotic injury, and a medial clear space larger than a superior clear space is indicative of deltoid injury. Additional quantitative measurement of all syndesmotic parameters with repeated radiographs of the ankle cannot be done reliably and therefore are of little value.