Osteoid osteoma of the proximal femur: treatment by percutaneous bone resection and drilling (PBRD). A report of 44 cases.

INTRODUCTION

Osteoid osteoma is a benign osteogenic tumor that is mainly located in the lower limbs. According to Campanacci the proximal femur is involved in 25% of cases. We present a series of 44 cases of osteoid osteoma located in the neck of the femur or the lesser trochanter treated by the minimally invasive method, CT-guided percutaneous bone resection and drilling (PBRD).

MATERIALS AND METHODS

This series included 44 patients, 20 girls and 24 boys, treated between 1987 and 2012. The average age at surgery was 12.7 years old (range 4-34). The diagnosis was based on the "association" of scintigraphy (hyperfixation) - CT scan (nidus located on the femoral neck or near the lesser trochanter). These patients underwent CT-guided PBRD under general anesthesia. Specific ancillary material was used to reach and remove the nidus and a cylinder of bone was sent to the pathologist for assessment. A lateral or anterior approach was used in all cases except one in which a posterior incision was made. Histological confirmation was obtained in 23 cases (the bone fragment was damaged in 21 cases).

RESULTS

Forty-two patients were reviewed after a minimum follow-up of one year (12-56 months). Two patients were lost to follow-up. Results were evaluated clinically and on CT scan 1 year after surgery: there were 35 cures with complete and permanent pain relief. There were 5 failures and 1 case of recurrence requiring a second CT-guided PBRD procedure as well 2 complications involving femoral fracture (one associated with failure).

DISCUSSION

The proximal femur is a common location of osteoid osteoma. Treatment requires careful preoperative planning to determine the surgical approach for safe removal. PBRD is a minimally invasive technique, allowing complete resection with suitable ancillary equipment. This method should be compared with thermoablation, which is a similar technique.

CONCLUSION

CT-guided PBRD is a therapeutic option in case of osteoid osteoma of the proximal femur.

LEVEL OF EVIDENCE

Level IV.