Ankle injuries are a frequent cause of patient visits to the emergency department and orthopaedic and primary care offices. Although lateral ligament sprains are the most common pathologic conditions, peroneal tendon subluxations occur with a similar inversion mechanism. Multiple grades of subluxation have been described with a recent addition of intrasheath subluxation. Magnetic resonance imaging is the best imaging modality to view the peroneal tendons at the retrofibular groove. Currently, point-of-care ultrasound is gaining clinical ground, especially for the dynamic viewing capability to capture an episodic subluxation. Although conservative treatment may be attempted for an acute injury, it has a low rate of success for the prevention of recurrent subluxation. Surgical procedures of various techniques have resulted in excellent recovery rates and faster return to play. The aim of this paper was to give a complete review of the current literature on peroneal tendon subluxation and to propose a clinical algorithm to help guide diagnosis and treatment. The goal of this study was to heighten clinical awareness to improve earlier detection and treatment of this sometimes elusive diagnosis.

Objective: To present a case of ultrasonic diagnosis and nonoperative management of a complete proximal rectus femoris avulsion in a National Collegiate Athletic Association Division 1 soccer goalkeeper.Background: While delivering a goal kick, a previously uninjured 24-year-old collegiate soccer goalkeeper had the sudden onset of right anterior thigh pain. He underwent rehabilitation with rapid resolution of his presenting pain but frequent intermittent recurrence of anterior thigh pain. After he was provided a definitive diagnosis with musculoskeletal ultrasound, he underwent an extended period of rehabilitation and eventually experienced complete recovery without recurrence.Differential Diagnosis: Rectus femoris avulsion, rectus femoris strain or partial tear, inguinal hernia, or acetabular labral tear.Treatment: Operative and nonoperative options were discussed. In view of the player's recovery, nonoperative options were pursued with a good result.Uniqueness: Complete proximal rectus femoris avulsions are rare. Our case contributes to the debate on whether elitelevel kicking and running athletes can return to full on-field performance without surgery.Conclusions: Complete proximal rectus femoris avulsions can be treated effectively using nonoperative measures with good preservation of function even in the elite-level athlete. In addition, musculoskeletal ultrasound is an excellent tool for onsite evaluation and may help guide prognosis and management.

H yponatremia in exercise is a potentially dangerous clinical scenario previously thought to be limited to exercise bouts of long duration and associated with excessive water intake. We report the case of a healthy young athlete with hyponatremia after moderate-duration exercise and only moderate water intake. CASE REPORTA 19-year-old female novice triathlete presented with abrupt onset of dull, bioccipital headache associated with mild photophobia; nausea with clear, watery emesis; and generalized malaise 90 minutes after completing a sprint distance event (0.4-km swim, 17-km bike, and 5-km run) in 1 hour 33 minutes. The outdoor ambient temperature at the race's completion at approximately 9 AM was 32°C. She reported hydration with 3 L of water the evening before the race, approximately 500 mL during the race, and 700 mL after the race. Her food intake was minimal on the morning of the race.Although she was an inexperienced triathlete, she was physically fit (weight, 57 kg; height, 160 cm; body mass index, 22 kg/m 2 ) and finished the race first among female novices. The patient's medical history included exercise-induced bronchospasm and a seizure disorder that had been asymptomatic for years. For seizure prophylaxis, she was taking carbamazepine and lamotrigine, tapering down her carbamazepine while increasing her lamotrigine. Serum levels of carbamazepine and sodium drawn 3 days before the race were 5.7 mg/mL (therapeutic range, 4-10 mg/mL) and 142 mmol/L, respectively.Physical examination revealed an oral temperature 36.1°C, heart rate of 70 beats/min, blood pressure of 128/82 mm Hg without orthostatic change, and respiratory rate of 12 breaths/min. She was alert and oriented, with equal and reactive pupils, intact extraocular motion, and a noticeable tearing mechanism. Her oral mucus membranes were moist, her skin was cool and moist, and she had no detectable edema. Findings on cardiac, pulmonary, abdominal, and neurologic examinations were all normal, as was her mental status. Possible hyponatremia was diagnosed, and she was transported to a local emergency department for further evaluation and management.Laboratory studies in the emergency department confirmed the diagnosis: sodium, 127 mmol/L; potassium, 3.5 mmol/L; chloride, 97 mmol/L; bicarbonate, 21 mmol/L; glucose, 4.8 mmol/L; creatinine, 88.4 mmol/L; urea nitrogen, 3.6 mmol/L; and serum osmolality, 254 mOsm/kg.