Snapshot A 15-year-old boy presents to his pediatrician with left knee pain. He denies any trauma to the knee. He plays football for his high school team and attends practice regularly. On physical exam, the tibial tubercle is pronounced and there is tenderness to palpation over the affected area. The patient reports pain upon resisted knee extension. Introduction Clinical definition describes an apophysitis of the tibial tuberosity Etiology Pathogenesis repetitive traction of the apophysis of the tibial tuberosity results in microtrauma and micro-avulsion the proximal patellar tendon insertion separates from the tibial tubercle during healing there is callous deposition that leads to a pronounced tubercle Epidemiology Demographics male:female ratio more common in males age bracket 12-15 years of age in boys 8-12 years of age in girls Risk factors participating in sports Presentation Symptoms anterior knee pain Physical exam inspection enlarged tibial tubercle tenderness over tibial tubercle provocative test pain on resisted knee extension Imaging Radiographs recommended views lateral radiograph of the knee findings irregularity and fragmentation of the tibial tubercle Studies Diagnostic criteria a clinical diagnosis Differential Sinding-Larsen-Johansson syndrome chronic apophysitis or minor avulsion injury of the inferior patellar pole Osteochondroma of the proximal tibia Tibial tubercle fracture Patellar tendonitis also an overuse injury (jumping, running) chronic, episodic anterior knee pain worsened with stairs or prolonged sitting localized tenderness along the patellar tendon, at the inferior pole of the patella Treatment Conservative rest, analgesics, ice, and physical therapy indication first-line treatment for Osgood-Schlatter disease Operative ossicle resection and/or excision of the tibial tuberosity indication considered in patients who do not respond to conservative managament and after skeletal maturity Complications Tubial tubericle prominence persists Genu recurvatum Prognosis Self-limiting Responds well to conservative management