Second operation for slipped capital femoral epiphysis: pin removal.

Pin removal procedures were retrospectively reviewed for 43 hips in 31 patients. Original treatment had included use of Knowles, Steinmann, Hagie, and cannulated steel pins. Time to pin extraction ranged from 5 to 70 months. Average operative time was slightly more than 1 h and average blood loss was 127 ml. Bone overgrowth and difficult extraction was encountered with all pin types. Pin breakage during extraction was recorded with Steinmann and Knowles pins. Delay in return to full activity postoperatively was a common complaint. This study shows that pin removal is not without certain costs and risks.