A 12-year-old girl is brought to the clinic by her mother for evaluation of leg pain. The patient first noticed a dull ache in her left thigh a month ago. The pain is intermittent, worse after skipping rope with friends, and typically resolves after rest or ibuprofen. She does not recall any inciting injury to the leg. Prior to last month, the patient had never experienced any similar pain. Medical history is unremarkable. She takes no medications. Family history is notable for sickle cell disease. Temperature is 37.5 C (99.5 F). BMI is at the 97th percentile for age. The abdomen is soft with no hepatosplenomegaly. A few soft, nontender, mobile, 1-cm inguinal lymph nodes are palpable bilaterally. Skin examination reveals a few small, healing abrasions over the bilateral anterior knees. The left hip demonstrates decreased range of motion with internal rotation. There is no increased warmth over the joint. The left foot points laterally during ambulation. Which of the following is the most likely underlying cause of this patient's symptoms?

Question

A 12-year-old girl is brought to the clinic by her mother for evaluation of leg pain.  The patient first noticed a dull ache in her left thigh a month ago.  The pain is intermittent, worse after skipping rope with friends, and typically resolves after rest or ibuprofen.  She does not recall any inciting injury to the leg.  Prior to last month, the patient had never experienced any similar pain.  Medical history is unremarkable.  She takes no medications.  Family history is notable for sickle cell disease.  Temperature is 37.5 C (99.5 F).  BMI is at the 97th percentile for age.  The abdomen is soft with no hepatosplenomegaly.  A few soft, nontender, mobile, 1-cm inguinal lymph nodes are palpable bilaterally.  Skin examination reveals a few small, healing abrasions over the bilateral anterior knees.  The left hip demonstrates decreased range of motion with internal rotation.  There is no increased warmth over the joint.  The left foot points laterally during ambulation.  Which of the following is the most likely underlying cause of this patient's symptoms?

Quizplus · Accepted Answer

11ec25c8_d978_9d89_bc81_4fcc67ff6c55_MD0003_00 This obese (BMI >95th percentile) patient with dull thigh pain and decreased range of motion of the hip likely has slipped capital femoral epiphysis (SCFE). SCFE occurs when excessive shearing at the proximal femoral physis (growth plate) weakens the growth plate, causing anterosuperior displacement of the proximal femur diaphysis and giving the appearance of a posteriorly displaced femoral head. Obese adolescents are at highest risk due to increased mechanical strain on the hip. displacement of the proximal femur diaphysis Symptoms most commonly include chronic (>3 weeks), intermittent, dull pain/ache of the hip, thigh, or knee that is exacerbated by activity, as seen in this patient. The leg is typically externally rotated (foot pointed laterally), and gait may be altered due to pain. On examination, decreased range of motion (particularly internal rotation) and tenderness of the hip may be present. Abduction and external rotation of the thigh during passive flexion of the hip is characteristic. Diagnosis is confirmed by visualization of a posteriorly slipped femoral head on x-ray. x-ray (Choice A) Septic arthritis, a bacterial joint infection, presents with acute fever, joint pain, inability to bear weight, and a swollen, warm joint. In contrast, this patient is afebrile with chronic symptoms and no joint swelling. (Choice B) Expansion of malignant cells in the bone marrow is characteristic of leukemia, which can present with chronic bone pain. Systemic findings such as fever, weight loss, lymphadenopathy, and splenomegaly are typical. This patient is otherwise asymptomatic, and her soft, nontender, 1-cm inguinal lymph nodes are normal, physiologic nodes. (Choice D) Transient synovitis is characterized by self-limiting, intraarticular inflammation and presents in children age 3-8 with acute hip pain and limp following a viral illness. This patient's age and chronic symptoms make SCFE more likely. (Choice E) Vasoocclusive crisis due to red cell sickling causes bone pain in patients with sickle cell disease. Undiagnosed sickle cell disease is unlikely in this adolescent because pain crises typically present in early childhood. Educational objective: Slipped capital femoral epiphysis occurs when excessive shearing at the proximal femoral physis weakens the growth plate, causing displacement of the proximal femur diaphysis. Patients are classically obese adolescents with chronic, dull pain along the thigh or knee that worsens with activity. References: Slipped capital femoral epiphysis: prevalence, pathogenesis, and natural history. (http://www.ncbi.nlm.nih.gov/pubmed/23054509) Slipped capital femoral epiphysis. (http://www.ncbi.nlm.nih.gov/pubmed/30855886)

A 12-Year-Old Girl Is Brought to the Clinic by Her