Author: Frances Tao, MD, MPH
Co Author #1: Emily M. Miller, MD
Senior Editor: Justin Mark Young, MD
Editor: Kyle Yost, DO

Patient Presentation:
A 13-year-old previously healthy male presented to the emergency room with 6 days of right hip pain and fever.

History:
He stated that while sitting in class, he felt a sudden throbbing ache in his right anterolateral hip. This pain worsened upon standing and walking. There was no radiation of pain or paresthesia. He denied hip trauma, however he recently sustained a superficial abrasion to his right knee while playing basketball. Despite acetaminophen and ibuprofen every six to eight hours, he continued to have pain fevers. His maximum temperature was 101 degrees Fahrenheit, and his symptoms progressively worsened, causing inability to ambulate. He denied upper respiratory infection symptoms, abdominal pain, nausea, vomiting, diarrhea, dysuria, or urethral discharge. He was up-to-date on vaccinations. There was no family history of joint disease, autoimmune disease, or malignancy. He had never been sexually active, and denied use of tobacco, alcohol, or drugs.

Physical Exam:
His vital signs on presentation included a temperature of 101 degrees Fahrenheit, a heart rate of 84, a blood pressure of 116/68, a respiratory rate of 22, and an oxygen saturation of 97% on room air.

On exam:
General: He was a well-developed well-nourished teenage male in no acute distress.
Cardiovascular: He had a regular rate and rhythm, without murmurs.
Respiratory: His lungs were clear to auscultation bilaterally, without wheezes or rales.
Musculoskeletal: He had normal muscle bulk and alignment of his right lower extremity. He did not have any rashes, erythema, or swelling over the right hip. He was unable to flex actively beyond 90 degrees, and had significant pain on passive hip flexion beyond 90 degrees. He had significant pain with log roll, internal and external rotation, and axial loading of the right hip. He had painless full range of motion of his right knee, ankle, and toes. There was a healing scab noted over the right patella, without active bleeding or drainage. He had 2+ distal pulses. Sensation was intact over all dermatomes. Compartments were soft and compressible.

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