Introduction: Anterior Cervical Discectomy and Fusion (ACDF) is currently the gold standard treatment for cervical spondylosis. Stand-alone intervertebral cages are a common way of achieving fusion however there is currently a lack of consensus in the literature regarding which type of bone graft is superior: autograft or allograft. Autograft bone is classically harvested from the iliac crest and studies support superior bone fusion compared to allograft, but contradictory studies exist and bone harvesting is related to donor site morbidity. The purpose of this study is to evaluate fusion after ACDF using a stand-alone intervertebral cage packed with autologous cervical bone shavings acquired during the procedure.

Methods: Twenty patients that underwent single-level anterior cervical discectomy and fusion from 2011 to 2014 using a stand-alone polyetheretherketone (PEEK) cage were recruited with no revision surgery cases. Patients were evaluated for evidence of bone fusion by plain films and CT scan. Fusion was assessed by grading the level of trabecular bridging bone across the bone-graft interface and evaluating for the presence of radiolucent gaps and bone sclerosis. Non-union was assessed and defined as greater than 1 mm in the interspinous distance on flexion-extension lateral radiographs. Odom’s criteria were used to assess clinical outcome.

Results: All interbody disc spaces achieved successful fusion at follow-up. A total of 80% (16/20) of patients had radiographic evidence of trabecular bone present both within and around the cage. The other 20% (4/20) exhibited bridging bone within the cage but had evidence of minor radiolucent gaps and lack of bridging bone completely surrounding the cage. Four patients exhibited non-union and three patients exhibited bone sclerosis. Eighty percent (16/20) of patients reported excellent/good clinical outcomes.

Conclusions: ACDF using a PEEK stand-alone cage with autograft bone shavings has a high rate of fusion and avoids potential complications of classic autograft harvesting and decreased allograft fusion rates.

Patient Care: My research will improve patient care in the following ways: 1) Reduce the frequency of multiple postoperative CT scans assessing bone fusion due to high rates of fusion, leading to reduced radiation exposure and reduced hospital spending / resources, 2) Continue to shift the ACDF treatment paradigm away from iliac crest autograft and provide an alternative to expensive allograft substitutes with autograft bone shavings in a cage.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the differences between autograft and allograft fusion and common approaches to autograft fusion, 2) Understand the ACDF procedure and radiological methods of assessing postoperative bone fusion, and 3) The pros and cons of using autograft bone shavings with a PEEK cage versus other fusion methods

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