Posterolateral spinal fusion at unintended levels due to bone-graft migration: No effect on clinical outcome in 19/130 patients

• Published in: Acta orthopaedica Vol. 72; no. 4; pp. 354 - 358
• Main Authors: Christensen, Finn B, Laursen, Malene, Gelineck, John, Hansen, Ebbe S, Bünger, Cody E
• Format: Journal Article
• Language: English
• Published: Basingstoke Informa UK Ltd 2001; Taylor & Francis
• Subjects: Activities of Daily Living; Adult; Aged; Biological and medical sciences; Bone Screws - adverse effects; Bone Screws - standards; Bone Transplantation - adverse effects; Bone Transplantation - methods; Female; Humans; Joint Instability - diagnostic imaging; Joint Instability - surgery; Low Back Pain - diagnostic imaging; Low Back Pain - surgery; Lumbar Vertebrae; Male; Medical sciences; Middle Aged; Orthopedic surgery; Pain Measurement; Prospective Studies; Radiography; Risk Factors; Spinal Fusion - adverse effects; Spinal Fusion - instrumentation; Spinal Fusion - methods; Spondylolisthesis - diagnostic imaging; Spondylolisthesis - surgery; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surveys and Questionnaires; Treatment Outcome; Human; Postoperative; Prognosis; Lumbar spine; Lateral; Migration; Symptomatology; Orthopedic surgery; Fixation; Treatment; Follow up study; Posterior; Arthrodesis; Complication; Graft; Surgical approach; Bone; Technique
• DOI: 10.1080/000164701753542005
• ISSN: 1745-3674; 0001-6470

In a prospective randomized study, we evaluated the risk of lumbar posterolateral spinal fusion at an unintended level due to bone graft migration. 130 patients underwent fusion supplemented by pedicle screw fixation (Cotrell-Dubousset, 64 patients) or uninstrumented fusion (66 patients). This was assessed by two independent observers on antero-posterior, and lateral radiographs taken 1 year after surgery. All patients had ben operated on at the preoperatively planned levels. Both observers agreed that fusion had taken place at an unintended level in 19 cases (14%). We found a tendency towards a higher risk of this "complication" when using supplementary pedicle screw fixation. The functional outcome, assessed by the Dallas Pain Questionnaire and the Low Back Pain Rating scale, was similar in patients having fusion at an unintended level and in patients fused only at the intended levels. There was no difference between the two groups concerning reoperation rates, postoperative smoking or social status. We conclude that unintended fusion occurs and tends to be commoner with the use of pedicle screw instrumentation. However, this complication seems not to affect the functional outcome if fusion has taken place at the intended level.