Clinical and radiographic assessment of transforaminal lumbar ...

BACKGROUND CONTEXT: Studies have suggested that the use of bone marrow aspirate (BMA) with HEALOS (DePuy Spine, Raynham, MA), a collagen-hydroxyapatite sponge (CHS), is an effective substitute for autologous iliac crest bone graft when used in fusion procedures of the lumbar spine. PURPOSE: To assess clinical and radiographic outcomes after implantation of BMA/CHS in patients undergoing transforaminal lumbar interbody fusion (TLIF) with posterolateral fusion (PLF). STUDY DESIGN/SETTING: Case series radiographic outcome study. PATIENT SAMPLE: Twenty patients. OUTCOME MEASURES: Radiographs/computed tomography (CT) scans. METHODS: From September 2003 to October 2004, 20 patients (22 interbody levels) were implanted with BMA/CHS via TLIF/PLF with interbody cages and posterior pedicle screws. All patients were retrospectively identified and invited for a 2-year prospective follow-up. Plain radiographs with dynamic films and CT scans were taken, and fusion was assessed in a blinded manner. RESULTS: Follow-up averaged 27 months (range: 24-29). Primary diagnosis included spondylolisthesis (17 patients), scoliosis with asymmetric collapse (2 patients), and postdiscectomy foraminal stenosis (1 patient). The overall fusion rate was 95% (21/22 levels, 19/20 patients). Anteriorly bridging bone was observed in 91% of the anteriorly fused levels (20/22), of which 65% (13/20) occurred through and around the cage and 35% (7/20) around the cage only. Unilateral or bilateral bridging of the posterior fusion masses was observed in 91% (20/22), with 55% occurring bilaterally (12/22). In 4 (18%) cases, bridging only occurred either posteriorly (2 cases) or anteriorly (2 cases). Complications included one deep wound infection. CONCLUSIONS: At the 2-year follow-up, BMA/CHS showed acceptable fusion rates in patients undergoing TLIF/PLF, and can be considered as an alternative source of graft material.