Oxiplex reduces leg pain, back pain, and associated symptoms after lumbar discectomy.

STUDY DESIGN: Prospective, randomized, blinded clinical trial. OBJECTIVE: To evaluate effectiveness of Oxiplex gel for reduction of pain and associated symptoms after lumbar discectomy. SUMMARY OF BACKGROUND DATA: Oxiplex gel (carboxymethylcellulose, polyethylene oxide, and calcium) is used during discectomy to coat the surgical site for reduction of pain and symptoms after lumbar discectomy. METHODS: Patients undergoing single-level lumbar discectomy performed by laminectomy or laminotomy and randomized to receive either surgery plus Oxiplex gel (treatment group) or surgery alone (control group) were assessed 6 months after surgery using (1) a quality of life questionnaire (Lumbar Spine Outcomes Questionnaire [LSOQ]) and (2) clinical evaluations. RESULTS: There were no statistically significant differences in baseline demographics, surgical procedures, LSOQ scores, and clinical evaluations between treatment (N = 177) and control (N = 175) groups. More gel-treated patients were satisfied with outcome of their surgical treatment than control patients (P = 0.05). The gel-treated group showed greater reductions in pain and symptoms from baseline compared with surgery-only controls. Additional benefits of gel were consistently shown in reduction of leg and back pain at 6 months in the patient population having substantial back pain at baseline (greater than or equal to the median LSOQ pain score of 63). In that population, there was a statistically significant reduction of leg pain and back pain (P < 0.01) in the treatment group compared with controls. Fewer patients in the treatment group had abnormal musculoskeletal physical examinations at 6 months compared with controls. There were no cases of cerebrospinal fluid leaks and no differences in laboratory values or vital signs. Patients in the treatment group had less hypoesthesia, paraesthesia, sensory loss, and fewer reoperations during the 6-month follow-up than controls (1 vs. 6). CONCLUSION: These data demonstrate improvements in clinical outcomes resulting from the use of Oxiplex gel in discectomy procedures for treatment of lumbar disc herniation.

Fractures of the thoracolumbar spine sustained by soldiers in vehicles attacked by improvised explosive devices.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To analyze the types of orthopedic spine fractures sustained by North Atlantic Treaty Organization soldiers when vehicles are attacked by improvised explosive devices (IEDs), with specific focus on the flexion-distraction type thoracolumbar fracture (Chance fracture). SUMMARY OF BACKGROUND DATA: Operation Enduring Freedom is the North Atlantic Treaty Organization's effort in Afghanistan. IED attacks on armored vehicles are common and account for high proportion of soldiers' deaths and injuries. METHODS: Retrospective record review was accomplished on soldiers admitted to a military hospital with orthopedic spine fractures after IED attacks on vehicles from January 1, 2008 to May 15, 2008. Thoracolumbar fractures were classified using the McAfee classification system. RESULTS: Twelve male patients with 16 thoracolumbar fractures were identified (3 patients with multiple fractures). The 16 thoracolumbar fractures included 6 flexion-distraction fractures in 5 patients (38%, 6/16: two T12, two L1, one L3, and one L4), 7 compression fractures in 5 patients (44%, 5/16; one T7, one T8, two L1, one L2, one L3, and one L4), and 3 burst fractures (19%, 3/16; two L1 and one L2). CONCLUSION: The incidence of flexion-distraction thoracolumbar (Chance) fractures has been reported to be between 1.0% and 2.5% in most spine fracture series. In this small study, Chance fractures represented 38% of all tho-racolumbar fractures sustained after IED attack on armored vehicles. The blast pattern associated with IED explosion may be responsible for the high rate of these injuries in vehicle occupants.

Transverse process fusion with bovine anorganic bone.

A biodegradable collagen membrane and bovine anorganic bone were studied in a rabbit spine fusion model. The bovine, anorganic bone is a nonantigenic, acellular clinical product used as a bone substitute for dento-alveolar applications. We reasoned this product with a collagen membrane could be useful for spine fusions. Our hypothesis was that bovine, anorganic bone, and a collagen membrane would promote spine fusion equivalent to an autogenous bone graft. To test the hypothesis, the transverse processes of the fourth and fifth lumbar vertebrae were decorticated in 30 rabbits divided equally among five groups. In one group, following decortication, no treatment was administered, whereas in the remaining four groups, treatments consisted of either autograft, collagen membrane, anorganic bone, or anorganic bone plus collagen membrane. Rabbits were euthanized 6 weeks after surgery, and the lumbar vertebrae were removed, radiographed, and processed for histology. The radiographs and histological sections were subjected to quantitative morphometric analyses and post hoc statistical testing (p < or = 0.05). We determined anorganic bone without a collagen membrane migrated into the soft tissues contiguous to the transverse processes. However, with a collagen membrane, the anorganic bone remained at the implant site, causing an osseous fusion of the transverse processes. Although the autograft promoted the greatest amount of new bone formation, significant transverse process fusion was accomplished with the anorganic bone and collagen membrane. Additional longer term studies are contemplated to validate feasibility of this clinical option, including a biomechanical component.