부산대학교 도서관

HISTORY: A 14-year-old male presented with left foot pain for 1 week. He was playing wiffleball over the weekend and noticed severe pain the next day; he went on to develop foot swelling. He reported similar symptoms 3 months prior and was treated with a CAM boot for 2 weeks. He also had 2 previous episodes of right knee pain and swelling, and underwent joint aspiration during one of these episodes, which was negative for infection. Labs were significant for mildly elevated CRP 3.4 and ESR 39. RF, ANA, and lyme PCR were all negative. During the second episode of right knee swelling, MRI showed a 2mm full-thickness chondral defect in the medial femoral condyle and diffuse myositis. The patient underwent arthroscopic chondroplasty. PHYSICAL EXAMINATION: Examination of the left foot revealed diffuse edema over the dorsal aspect of the foot to the level of the ankle, no erythema or warmth, tender to palpation over the 2nd and 3rd metatarsal heads, limited flexion and extension of digits 2-5 secondary to pain and swelling, normal sensation, brisk capillary refill; left ankle was normal. DIFFERENTIAL DIAGNOSIS: Metatarsal fracture; Metatarsal stress fracture or stress reaction; Freiberg's infarction; Plantar plate rupture; Synovitis TEST AND RESULTS: X-ray of left foot: No osseous abnormalities No substantial soft tissue swelling or joint effusion MRI of left foot: Increased bone marrow signal in distal aspect of second and third metatarsals and metatarsal heads, effusions of 2nd and 3rd MTP joints; No underlying fracture; Plantar plate intact; Tendons intact and normal FINAL WORKING DIAGNOSIS: Stress reaction; extraintestinal manifestation of inflammatory bowel disease TREATMENT AND OUTCOMES: Immobilization with CAM boot for 3 weeks. On repeat exam foot pain and swelling had resolved, patient was transitioned out of CAM boot successfully. One month later began having polyarthritis (swelling of right knee and right elbow), abdominal pain and low grade fevers; eventually diagnosed with Crohns' disease.