Acute lateral ankle sprain accounts for 85% of sprains. The lateral sprain is associated with other ligament injuries e.g. medial and syndesmosis sprain. Long-term, approximately 20% of acute lateral sprains develop into chronic lateral ankle instability (CLAI) which includes persistent pain, and recurring ankle sprains. This study evaluated the grade of an ankle ligament injury by ultrasonography (US) and compared the findings to the outcome of patient-reported questionnaires. 48 subjects (18–40 years) diagnosed with an ankle sprain attended a clinical and US examination of ankle ligaments within two weeks after the sprain. Evaluation was done by US of acute lateral ligament injuries (ATFL, CFL), syndesmosis injury (AiTFL), and medial injury (dPT, TCt) only in participants with the positive clinical signs of medial injury. Participants were then mailed a questionnaire (PROMQ) every third month for a year. 29 women and 19 men participated with a mean age at 26.50 years. One-year follow-ups need to be analyzed further for final results. Temporary results include data based on the initial 26 patients: Two clinical signs statistically correlated. Multiple logistic regression analysis confirmed the results. Positive palpated tenderness AiTFL predicted with partial ruptured ATFL and reported pain during active plantar flexion of ankle predicted with normal CFL confirmed by the US. Patients with partial rupture of ATFL presented with tenderness at AiTFL point. Patients presenting with intact CFL reported pain during active plantar flexion. Compared to the US findings, the overall examinations were inconclusive in predicting ATFL, CFL, AiTFL, and medial ligament injuries.

This study sought to determine the genetic contribution of Perthes' disease, using the world's largest twin-registry.

We extracted all twin pairs from the Danish Twin Registry (DTR) in which at least one individual had Perthes' Disease. The DTR captures every twin pair born alive in Denmark. Those with Perthes' disease were identified using health record linkage to the Danish Morbidity Record. Probandwise concordance was calculated to describe the likelihood that any given individual had LCPD if their co-twin was also diagnosed.

There were 81 twin pairs; 10 monozygotic (MZ), 51 dizygotic (DZ), and 20 unclassified (UZ). There was no association between birth weight and being the affected co-twin. Four pairs (two dizygotic and two unclassified) were concordant for LCPD, which is greater than would be expected assuming no familial aggregation. There were no concordant MZ twin pairs. The overall probandwise concordance was 0.09 (95% CI 0.01–0.18): 0.00 for the MZ, 0.08 (95% CI 0.00–0.18) for the DZ, and 0.18 (95% 0.00–0.40) for the UZ twin pairs.

This study found evidence of familial clustering in LCPD but did not demonstrate a genetic component. The absolute risk that a co-twin of an affected individual will develop LCPD is low, even in the case of MZ twin pairs.