Prospective clinical and radiographic evaluation of an allogeneic bone matrix containing stem cells (Trinity Evolution® Viable Cellular Bone Matrix) in patients undergoing two-level anterior cervical discectomy and fusion.

BACKGROUND: Trinity Evolution® (TE), a viable cellular bone allograft, previously demonstrated high fusion rates and no safety-related concerns after single-level anterior cervical discectomy and fusion (ACDF) procedures. This prospective multicenter clinical study was performed to assess the radiographic and clinical outcomes of TE in subjects undergoing two-level ACDF procedures. METHODS: In a prospective, multicenter study, 40 subjects that presented with symptomatic cervical degeneration at two adjacent vertebral levels underwent instrumented ACDF using TE autograft substitute in a polyetherethereketone (PEEK) cage. At 12 months, radiographic fusion status was evaluated by dynamic motion plain radiographs and thin cut CT with multiplanar reconstruction by a panel that was blinded to clinical outcome. Fusion success was defined by angular motion (≤4°) and the presence of bridging bone across the adjacent vertebral endplates. Clinical pain and function assessments included the Neck Disability Index (NDI), neck and arm pain as evaluated by visual analog scales (VAS), and SF-36 at both 6 and 12 months. RESULTS: At both 6 and 12 months, all clinical outcome scores (SF-36, NDI, and VAS pain) improved significantly (p < 0.05) compared to baseline values. There were no adverse events or infections that were attributed to the graft material, no subjects that required revisions, and no significant decreases to mean neurological evaluations at any time as compared to baseline. At 12 months, the per subject and per level fusion rate was 89.4 and 93.4%, respectively. Subgroup analysis of subjects with risk factors for pseudoarthrosis (current or former smokers, diabetic, or obese/extremely obese) compared to those without risk factors demonstrated no significant differences in fusion rates. CONCLUSIONS: Patients undergoing two-level ACDF with TE in combination with a PEEK interbody spacer and supplemental anterior fixation had a high rate of fusion success without any serious adverse events related to the graft material. TRIAL REGISTRATION: Trinity Evolution in Anterior Cervical Disectomy and Fusion (ACDF) NCT00951938.

Facet-sparing decompression with a minimally invasive flexible microblade shaver: a prospective operative analysis.

STUDY DESIGN: This is a detailed description of a facet-sparing decompression technique and a prospective observational study of 59 subjects. OBJECTIVE: To describe a facet-sparing decompression technique, quantify operative parameters, adverse events, and anatomic changes following decompression with a flexible microblade shaving system. SUMMARY OF BACKGROUND DATA: Decompression in patients with lumbar spinal stenosis is a common surgical procedure. However, obtaining a thorough decompression while leaving enough tissue to avoid destabilization can be challenging. Decompression with a flexible, through-the-foramen system may mitigate some of these challenges. MATERIALS AND METHODS: Fifty-nine subjects diagnosed with lumbar spinal stenosis were recruited into this study. Subjects underwent decompression with a flexible, microblade decompression system at a total of 88 levels between L2 and S1. Subject demographics, details of the procedure, and operation, including adverse events were collected. Preoperative and postoperative computed tomography scans and plain radiographs were obtained from a subset of 12 subjects and quantitatively assessed for bone removal and preservation of stabilizing structures. RESULTS: Fifty-nine subjects had 88 levels treated, 51% single-level and 49% 2-level with L4-L5 being the most commonly decompressed level. Operative time, blood loss, and length of stay were similar to or less than that seen in the historical control. The system was successfully used for decompression in 95.8% of the attempted foramina. Three operative complications were reported, all dural tears (5.1%). These dural tears occurred before introduction of the flexible decompression system. Computed tomography scans from 12 subjects demonstrate access to the lateral recess and foramen with removal of <6% of the superior facet cross-sectional area. CONCLUSIONS: The flexible microblade shaving system provided thorough decompression with few intraoperative complications. Operative variables were favorable compared to the literature and radiographic decompression was achieved to a great extent while allowing for the preservation of the facet joints and midline structures.

Risk factors for surgical site infection in the patient with spinal injury.

STUDY DESIGN: A retrospective chart review of 1561 patients with spinal injury was conducted over a 4-year period. OBJECTIVES: To determine the rate of surgical site infection in the spinal trauma population, to compare infection rates after spinal operations for elective and traumatic indications, and to identify risk factors for postoperative wound infections in the traumatic subpopulation. SUMMARY OF BACKGROUND DATA: Surgical site infection after spinal operations is a dreaded complication. Risk factors have been investigated previously, but the subset of patients with acute traumatic spinal injury may be distinct. METHODS: The hospital's infection control program was used to identify surgical site infections after spinal operations, and infection rates were calculated. Data including patient characteristics, severity of injury indicators, surgical factors, and perioperative management factors were collected for the patients presenting with acute spinal injury over a 4-year period. RESULTS: Postoperative wound infections developed in 24 of 256 patients. This infection rate of 9.4% was significantly (P < 0.001) higher than for elective spinal operations during the same period (3.7%). Risk factors found to be independently significant included delay until operation, increased postoperative intensive care unit stay, single (neurosurgical or orthopedic) versus combined operative team. CONCLUSIONS: Risk factors for surgical site infection in the acute trauma setting are identified. Two surgical teams may be involved without causing a higher rate of infection.