gms | German Medical Science

Objective: Unstable osteoporotic fractures require often 360 degrees Fusion with posterior pedicle Fixation and a vertebral body replacement with a distractible cage. We analyzed the thoracolumbar geometry before and after both procedures.

Methods: Twenty-six consecutive patients (20 female, 6 male) with osteoporotic fractures of the thoracic and lumbar spine who underwent 360-degree fusion with posterior fixation using Polymethyl-methacrylate augmented pedicle screws and an expandable cage at our department between May 2013 and March 2015 were included. The mean age was 71.73 ± 12.51 years (range 47 - 91 years). Since 3 patients had 2 non-adjacent fractures, we performed 29 corpectomies (16 lumbar, 13 thoracic).The cranial most level was Th3 the caudal most level was L5. All patients underwent a baseline physical and neurological examination on admission. The diagnostic routine included MRI X-ray and CT scans. Postoperative measurements were done on upright x-rays following mobilization of the patient. The pre-/inter-/postoperative kyphosis/lordosis angle of the adjacent endplates was assessed.

Results: The mean local lordosis angle prior posterior fixation was -14.17 ± 22.41 degrees. For the patients with fractures of the thoracic spine, this was -28.00 ± 15.29 degrees (range -57.80 – -3.90 degrees) and for patients with lumbar spine fractures 0.20 ± 17.23 degrees (range -20.50 – 30.60 degrees) respectively. After posterior fixation the average lordosis angle was -6.14 ± 20.56 degrees. It was -17.71 ± 13.83 (range -47.60 – 5.10 degrees) for thoracic fractures and 6.32 ± 16.98 degrees (range -16.50 – 32.10) for lumbar fractures. After the anterior column reconstruction and ambulation the local lordosis angle averaged at -5.15 ± 21.21 degrees. The net lordosis gain was 7.05 ± 5.86 degrees (range -6.10 – 19.70 degrees) for the lumbar fracture group, whereas it was 9.31 ± 15.34 degrees (range -4.10 – 48.00 degrees) for the thoracic fracture group. We found no statistically significant difference between the pre-surgery and post-surgery measurements. There was no significant difference between the amount of lordosis restoration between the thoracic and lumbar fracture groups either.

Conclusion: The 360-degree Fusion with augmented pedicle screw fixation and anterior reconstruction with a distractible cage allowed a correction of the posttraumatic deformity by an average 9 degrees Lordosis. The correction was maintained on autonomous ambulation.