Grafted Vertebral Fracture after Implant Removal in a Patient with Spine-shortening Vertebral Osteotomy

We experienced the rare complication of a vertebral fracture that was caused by implant removal after bony fusion had been achieved in a patient who underwent spine-shortening osteotomy (SSO) for tethered cord syndrome (TCS). We propose that the removal of the implant used for SSO should be contraindicated. The patient (a 27-year-old female) presented to our institution with a history of progressive severe lower back pain, gait disturbance, and urinary incontinence. As an infant, she had undergone surgery for spina bifida with lipoma. Magnetic resonance imaging of the spine revealed tethering of the spinal cord to a lipoma. We performed SSO at the level of the L1 vertebra level. After spine shortening and fixation using a posterior approach, the L1 vertebral body was completely removed anteriorly and replaced with a left iliac bone graft. The patient's symptoms improved after surgery. After bony fusion was achieved after surgery, we decided to remove the spinal implant after we explained the advantages and disadvantages of the procedure to the patient. We performed implant removal surgery safely 2 years later; however, the patient complained of severe lower back pain 10 days after the surgery without any history of trauma. Reconstruction computed tomography showed fracture of the grafted vertebra. We performed a repeat posterior fixation, which relieved the lower back pain; she has experienced no complications in the subsequent 5 years. In summary, we report a case of a rare complication of the fracture of a grafted vertebra after removal of an implant used in SSO for TCS. Spinal stability could not be maintained without the spinal posterior implant after SSO. Postoperative fracture after spinal implant removal is rare but possible, and patients must be informed of this potential risk.