A 13-year-old boy is brought to the office due to progressive pain of the left knee for 3 months. The pain initially occurred only after basketball practice but improved with rest and ibuprofen. However, over the last several weeks, the patient has had knee pain within the first 15 minutes of practice. Last week, the pain became so severe that he missed practice and a game. The patient has had no fever, weight loss, or night sweats. The pain has not caused him to awaken. Vital signs are normal. Physical examination reveals tenderness over the left tibial tubercle, which appears more prominent than the right. The left knee has full range of motion and no palpable effusion. Extension of the left knee against resistance and squatting reproduces the pain. Which of the following is the most likely cause of this patient's knee pain?

Question

A 13-year-old boy is brought to the office due to progressive pain of the left knee for 3 months.  The pain initially occurred only after basketball practice but improved with rest and ibuprofen.  However, over the last several weeks, the patient has had knee pain within the first 15 minutes of practice.  Last week, the pain became so severe that he missed practice and a game.  The patient has had no fever, weight loss, or night sweats.  The pain has not caused him to awaken.  Vital signs are normal.  Physical examination reveals tenderness over the left tibial tubercle, which appears more prominent than the right.  The left knee has full range of motion and no palpable effusion.  Extension of the left knee against resistance and squatting reproduces the pain.  Which of the following is the most likely cause of this patient's knee pain?

Quizplus · Accepted Answer

11ec25c8_d740_fd16_bc81_45f814fe0ae5_MD0003_00 Osgood-Schlatter disease is a common, benign cause of knee pain caused by overuse in young adolescents. During periods of rapid growth (typically age 13-14 for boys and 10-12 for girls), the quadriceps muscles pull on the insertion site of the patellar tendon. Pain occurs at this site, which is located on the apophysis of the tibial tubercle. This traction apophysitis may lead to elevation and chronic avulsion of the tibial tubercle. Patients have progressive pain over the tibial tuberosity that worsens with activities involving repetitive running, jumping, or kneeling (eg, soccer, basketball, gymnastics). Pain improves with rest and is more often unilateral than bilateral. Examination typically reveals prominence and tenderness over the tibial tubercle. Pain can be reproduced by squatting or extending the knee against resistance, as seen in this patient. The diagnosis is clinical. However, x-ray may be indicated for atypical findings (eg, erythema, pain unrelated to activity) and may reveal soft tissue swelling anterior to the tibial tubercle. Treatment is supportive, consisting of pain control (eg, nonsteroidal anti-inflammatory drugs), activity as tolerated, and physical therapy. Symptoms typically self-resolve on ossification of the tibial growth plate during adolescence. (Choice B) Patellar tendinitis is an overuse injury due to repetitive jumping (eg, basketball, volleyball). Patients have anterior knee pain that worsens with activity. Unlike Osgood-Schlatter disease (in which pain occurs over the tibial tuberosity), in patellar tendinitis, point tenderness is present at the inferior pole of the patella. (Choice C) Patellofemoral pain can be an overuse injury presenting as progressive knee pain in the setting of running and squatting. Pain is usually localized to the patella and associated with a sensation of instability or "buckling" at the knee. (Choice D) Prepatellar bursitis occurs after direct, chronic trauma (eg, wrestling) of the anterior knee. Symptoms include pain with direct pressure and superficial swelling over the patella, not the tibial tuberosity. (Choice E) Tibial osteomyelitis may present with local (eg, pain, erythema) and systemic (eg, fever) inflammation, in addition to refusal to bear weight on the affected extremity. Pain does not improve with rest alone. Educational objective: Osgood-Schlatter disease, a common cause of knee pain in young adolescents, is caused by a traction apophysitis of the tibial tubercle. Patients typically have pain exacerbated by activity, and examination reveals prominence and tenderness over the tibial tubercle. References: Osgood Schlatter disease. (http://www.ncbi.nlm.nih.gov/pubmed/28723024) Apophysitis of the tibial tuberosity (Osgood-Schlatter disease): a review. (http://www.ncbi.nlm.nih.gov/pubmed/27752406)

A 13-Year-Old Boy Is Brought to the Office Due to Progressive