The load sharing classification of spine fractures.
METHODS
A 3 to 4 year follow-up was performed on a consecutive series of 28 patients who had three-column spinal fractures surgically stabilized by short-segment instrumentation with first generation VSP (Steffee) screws and plates and autograft fusion. The follow-up revealed 10 patients with broken screws.


BACKGROUND
Retrospective examination of preoperative radiographs and computed tomographic axial and sagittal reconstruction images clearly demonstrated that the screw fractures all occurred in patients with a disproportionately greater amount of injury to the vertebral body.


RESULTS
A point system (the load sharing classification) was developed that grades: 1) the amount of damaged vertebral body, 2) the spread of the fragments in the fracture site, and 3) the amount of corrected traumatic kyphosis.


CONCLUSIONS
This point system can be used preoperatively to: 1) predict screw breakage when short segment, posteriorly placed pedicle screw implants are being used, 2) describe any spinal injury for retrospective studies, or 3) select spinal fractures for anterior reconstruction with strut graft, short-segment-type reconstruction.
Division of Orthopaedic Surgery, University of Missouri-Columbia Medical School.
T
T
McCormack
E
E
Karaikovic
R W
RW
Gaines
D000328:Adult; D001860:Bone Plates; D001863:Bone Screws; D004868:Equipment Failure; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016268:Internal Fixators; D008159:Lumbar Vertebrae / Q000293:injuries*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016103:Spinal Fractures / Q000145:classification / Q000453:epidemiology / Q000601:surgery*; D013123:Spinal Fusion / Q000295:instrumentation*; D013904:Thoracic Vertebrae / Q000293:injuries*; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016474:Weight-Bearing / Q000502:physiology