Recurrent intra-articular osteoid osteoma of the hip after radiofrequency ablation: a case report and review of the literature

We present a case of a 53-year-old woman with recurrent intra-articular osteoid osteoma of the hip 6 months after initial treatment with percutaneous radiofrequency ablation. En bloc surgical excision of the osteoid osteoma and prophylactic internal fixation for impending stress fracture was performed. The patient is pain free, has returned to normal function and there is no sign of recurrence at the one-year follow-up. Intraarticular osteoid osteoma, present a diagnostic challenge and often they are misdiagnosed. Minimally invasive ablation techniques can fail in significant percentage and then surgical excision with histological confirmation remains the definitive treatment of choice

Experimental Osteomyelitis Caused by Methicillin-Resistant Staphylococcus aureus Treated with a Polylactide Carrier Releasing Linezolid

Background: The effectiveness of a new delivery system consisting of polymerized dilactide (PLA) with incorporated linezolid was investigated in a rabbit model as a means of treating methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis. Methods: The PLA-linezolid system was prepared after thorough stirring of PLA with linezolid at a 10: 1 ratio. Experimental osteomyelitis was established in 40 rabbits by a modification of the Norden model with MRSA as the test isolate. After a hole had been drilled in the upper right femur, the isolate was inoculated using a thin needle working as a foreign body. At three weeks, the needle was removed and cultured, and the PLA-linezolid system was implanted in half the animals (group B); the remaining half was the control group (group A). Animals were sacrificed at regular intervals; tissue around the site of implantation was examined for pathologic changes and cultured quantitatively. Results: The prepared system eluted linezolid in vitro at concentrations much greater than the minimum inhibitory concentration (MIC) of the test pathogen for 11 days. At three weeks after inoculation of the test isolate, all animals had osteomyelitis. By the sixth week, bacterial growth from cancellous bone of group B was significantly lower than that in group A. However, this effect was not maintained until the end of the study (weeks 8 and 10), when the differences in bacterial growth in the two groups were not significant. Conclusion: Polymerized dilactide mixed with 10% linezolid achieved partial arrest of the offending pathogen in an experimental model of osteomyelitis caused by MRSA