Sacral inflammatory pseudotumor revealed by paraneoplastic syndrome.

There is still debate on whether inflammatory pseudotumor should be considered benign or malignant. This lesion has only been reported twice in bone, apart from cases complicating foreign body reaction to joint replacement arthroplasty. We report here a third case, localized at the sacrum. A 31-year-old man had inflammatory dorsalgia and polyarthralgia without synovitis but with fever, asthenia, and erythema nodosa. Biological tests and X-rays were not informative, but technetium scintigraphy revealed a high level of left sacroiliac tracer binding. Several nonsteroidal anti-inflammatory drugs and sulfasalazine treatment were given over 3 months but ineffective. Pelvic magnetic resonance imaging showed an osteolytic tumor of the sacrum. Biopsy suggested a malignant fibrosarcoma, but complete evaluation after surgical resection demonstrated an inflammatory pseudotumor. All clinical symptoms disappeared within a few days after surgery, which is suggestive of a paraneoplastic syndrome. No relapse has occurred after 4 years.

Upper cervical spine surgery in rheumatoid arthritis: retrospective study of 30 patients followed for two years or more after Cotrel-Dubousset instrumentation.

PURPOSE: To evaluate the efficacy of upper cervical spine surgery in symptomatic atlantoaxial instability due to rheumatoid arthritis (RA). MATERIAL AND METHODS: Thirty RA patients (29 women and one man) with a mean age of 56 years were studied retrospectively. Symptomatic forward slippage of the atlas on the axis with a synovial pannus surrounding the odontoid and magnetic resonance imaging evidence of spinal cord compression was present in all 30 patients; 18 patients had vertical translocation of the odontoid and 14 had basilar invagination. Surgery, performed between 1991 and 1997, consisted of occipitocervical fusion in 18 patients and atlantoaxial fusion in 12. Cotrel-Dubousset instrumentation was performed in all 30 patients. RESULTS: Mean follow-up was four and a half years. All patients were satisfied with the procedure and exhibited marked functional gains and objective neurological improvement (by one class in the Ranawat scheme). Stable fusion was documented in all 30 patients. CONCLUSION: Cervical instrumentation and bone grafting seems to provide functional and neurological gains in carefully selected RA patients with atlantoaxial instability and spinal cord compression. Long term follow-up suggests that the benefits are sustained and that morbidity is low.

Magnetic resonance imaging changes in periarticular soft tissues during flares of medial compartment knee osteoarthritis. Preliminary study in 10 patients.

OBJECTIVE: To quantify changes in magnetic resonance imaging signals from the deep and superficial capsulo-ligamentous planes and the medial collateral ligament in flares of knee osteoarthritis. PATIENTS AND METHODS: Preliminary prospective study of ten patients with medial compartment knee osteoarthritis meeting American College of Rheumatology criteria and associated with a Lequesne index of 5 or more. A grid was used to evaluate signal changes as compared to the opposite (asymptomatic) knee. Magnetic resonance images were read independently by two radiologists blinded to clinical data. RESULTS AND DISCUSSION: In all ten patients the capsulo-ligamentous planes and medial collateral ligament generated low signal on T1 images and high signal on T2 images. No significant changes were seen in the asymptomatic knee. The evaluation grid produced satisfactory interobserver agreement. CONCLUSION: Flares of medial compartment knee osteoarthritis are associated with changes in magnetic signal as compared to the contralateral asymptomatic osteoarthritic knee. The grid developed for this study could be used to evaluate the effects of treatment in a larger number of patients.