Secondary tethers after physeal bar resection: a common source of failure?

Despite a standardized operative technique and appropriate patient selection for physeal bar resection, a bar size less than 50% of the physis, and a prospective growth period greater than 2 years, failure may result. Limited growth because of poor function of the remaining physis and secondary tethers (incomplete resection or recurrence of the bar) may prevent reestablishment of growth or lead to its premature cessation. The current study investigated patients with insufficient restoration of growth by means of magnetic resonance imaging or computed tomography or both. Twenty-two patients had 24 physeal bar resections with interposition of autologous fat as the index procedure (Langenskiöld technique). Fourteen patients had only fair or poor results. Five patients had premature arrest of the affected physis with a postoperative growth period less than 1 year. Radiologic and clinical findings revealed bridge recurrence in four patients but no obvious reasons in the remaining five patients. Postoperative magnetic resonance imaging or computed tomography or both detected a secondary tether because of incomplete bar resection (one patient) or recurrence of the bar (four patients). Graft dislocation out of the resection cavity with an associated recurrence of the bar proved to be the underlying problem in three of the eight patients with bar recurrence. Magnetic resonance imaging is not only useful in preoperative mapping of physeal bars but also may help to explain failures after growth plate surgery.