WHAT'S KNOWN ON THIS SUBJECT: Although concussion is increasingly being diagnosed in the pediatric population, little is known about what factors lead to prolonged postconcussive symptoms in children. In particular, the effect of previous history of concussion on recovery from a repeat injury is unclear. WHAT THIS STUDY ADDS:Children with a history of previous concussion, particularly recent or multiple concussions, are at increased risk for prolonged symptoms after concussion. This suggests that repeat concussion, particularly within a vulnerable time window, may lead to longer duration of symptoms.abstract OBJECTIVE: To test the hypothesis that children with a previous history of concussion have a longer duration of symptoms after a repeat concussion than those without such a history.METHODS: Prospective cohort study of consecutive patients 11 to 22 years old presenting to the emergency department of a children' s hospital with an acute concussion. The main outcome measure was time to symptom resolution, assessed by the Rivermead PostConcussion Symptoms Questionnaire (RPSQ). Patients and providers completed a questionnaire describing mechanism of injury, associated symptoms, past medical history, examination findings, diagnostic studies, and the RPSQ. Patients were then serially administered the RPSQ for 3 months after the concussion or until all symptoms resolved.RESULTS: A total of 280 patients were enrolled over 12 months. Patients with a history of previous concussion had a longer duration of symptoms than those without previous concussion (24 vs 12 days, P = .02). Median symptom duration was even longer for patients with multiple previous concussions (28 days, P = .03) and for those who had sustained a concussion within the previous year (35 days, P = .007) compared with patients without those risk factors. In a multivariate model, previous concussion, absence of loss of consciousness, age $13, and initial RPSQ score .18 were significant predictors of prolonged recovery. CONCLUSIONS:Children with a history of a previous concussion, particularly recent or multiple concussions, are at increased risk for prolonged symptoms after concussion. These findings have direct implications on the management of patients with concussion who are at high risk for repeat injuries.

Chronic pain in the Achilles tendon is a common problem in both athletes and nonathletes alike. The etiology for the development of Achilles tendinopathy has not been fully elucidated, and there remains multiple theories to explain the pain and dysfunction accompanying this condition. The diagnosis of Achilles tendon problems continues to rely on the clinical history and physical examination. The optimal management of pain, restoration of function, and return-to-sports participation with Achilles tendinopathy are evolving because of the advancement in technologies and research regarding its pathophysiology. This article aims to provide a brief review of the relevant anatomy, differential diagnosis, imaging findings, and an update of the literature on conservative and minimally invasive managements of chronic Achilles tendinopathy.