Heterotopic Ossification Interfering With Lengthening of Magnetically Controlled Growing Rods: A Report of 2 Cases Managed With Excision and a PTFE Liner.

CASE: Two pediatric patients with early-onset neuromuscular scoliosis developed heterotopic ossification (HO) on the telescoping hub of magnetically controlled growing rods (MCGR), preventing lengthening. Resection of the circumferential HO and placement of a polytetrafluorethylene (PTFE) liner around the rod restored MCGR lengthening capabilities for 1.3 to 1.5 years after revision surgery, with no HO recurrence.

CONCLUSION

HO formation surrounding the telescoping portion of the MCGR is a possible cause for failure to lengthen. If found, resection and placement of a PTFE liner can restore MCGR lengthening.

LEVEL OF EVIDENCE: Level IV.