Osteoid osteoma of the patella: a case report.

Though osteoid osteoma is a common primary benign lesion of the bones, intra-articular involvement is rare and poses diagnostic difficulties when it affects middle-aged patients. We present the case of a 51-year-old woman with a 2.5 year history of anterior knee pain that was misdiagnosed as osteochondritis dissecans. Radiological findings were absent, whereas MRI showed a well-circumscribed lesion. A local excisional biopsy was performed and microscopic appearance confirmed diagnosis.

First sternocostal degenerative arthritis with intrarticular fluid collection. A case report.

A rare case with clinical condition of first sternocostal degenerative arthritis with intra-articular fluid collection that developed after long-lasting intense exercise (weight-lifting) for twenty years is reported. Imaging findings and differential diagnoses of the case are presented.

Osteoid osteoma of the patella. Case report and review of the literature.

Osteoid osteoma is a benign, bone-forming tumor. The diaphyses of the long bones are the sites of predilection (at least 50% of all cases occurring in the femur and the tibia). Also this lesion has a male preponderance and the majority of cases present in the second and third decade. We represent an unusual localization of osteoid osteoma in the patella of a 51-year old woman.

Septic arthritis caused by Erysipelothrix rhusiopathiae infection after arthroscopically assisted anterior cruciate ligament reconstruction.

A case of septic arthritis caused by Erysipelothrix rhusiopathiae, after an arthroscopically assisted anterior cruciate ligament (ACL) substitution in a non-immunosuppressed patient is described. An 18-year-old man underwent an ACL reconstruction with a quadruple hamstring graft. Eight days postoperatively, the patient developed fever, knee pain, and effusion without erythema or suppuration. He was readmitted to the hospital with the diagnosis of septic arthritis. The patient's erythrocyte sedimentation rate, C-reactive protein level, and white blood cell count were high. The joint was aspirated and the fluid was sent for cultures that revealed the presence of E rhusiopathiae. E rhusiopathiae is widespread in nature, it is transmitted by direct cutaneous laceration, and it causes septic arthritis, meningitis, endocarditis, and renal failure in immunosuppressed people with poor prognosis. In our case, the infection was treated with arthroscopic lavage and debridement, retention of the graft and hardware, and intravenous antibiotic administration for 6 weeks, followed by oral administration for 16 weeks.

Echinococcal synovitis of the knee joint.

Bone lesions are present in 1% to 2% of cases of hydatid disease. Hydatid synovitis can usually be identified due to secondary extension from the adjacent bone, or infrequently after hematogenous spread. We present an extremely rare case of hydatid synovitis without bony involvement. A 74-year-old man with diagnosed hydatid disease was admitted to our department because of left knee swelling. Neither physical examination nor laboratory studies revealed any remarkable findings. Radiographic evaluation of the knee joint was noncontributory. The patient underwent an arthroscopically assisted synovectomy, and the biopsy revealed an echinococcus contamination. No complications occurred during the postoperative period.