Posterior Lumbar Interbody Fusion Using a Porous PEEK Implant and Bone Marrow Concentrate
In posterior lumbar interbody fusion (PLIF) surgery, intradiscal implants are used to restore displace height, sagittal alignment and facilitate de novo bone growth across the vertebral interspace [1-4]. Porous PEEK implants have a surface architecture designed to promote bone in-growth while maintaining the favorable biomechanical and imaging properties [5-7]. The implant surface mimics bone with its highly porous interconnected architecture. The increased surface area and wicking capability of the porous surface improves host tissue to implant contact compared with traditional interbody implants. All patients had clinical complaints of low back pain and radiating leg pain that was unresponsive to a minimum of 8 weeks of nonoperative treatment that included immobilization, traction, modalities, medications, and physical therapy. In addition to recurrent or persistent complaints of pain, all patients had an objective neurologic deficit that included 1 or more of the following: an asymmetric deep tendon reflex, a sensory deficit in a dermatomal pattern, or motor weakness. All patients had a correlative neuroradiographic study. We recorded patients’ smoking status and presence of diabetes, osteoporosis, and obesity. Patients were excluded from the study if they had a medical condition that required medication, such as steroids or nonsteroidal anti-inflammatory medications, that could interfere with fusion. All patients had an open PLIF procedure; no out-patient surgeries were performed. We made a midline incision over the index level to expose the posterior spinal elements bilaterally and performed a unilateral or bilateral laminotomy. Next, the disc space was exposed and a discectomy was performed with removal of cartilaginous endplates and preservation of the bony endplates. We used no autogenous bone grafts or local host bone reamings. Fifty-five to 60 mL of bone marrow was aspirated from the pelvis and processed to produce a concentration of stem cells. The bone marrow aspirate was concentrated in a centrifuge in the operating room using the FDA-approved ART BMC Plus device (Celling Biosciences, Austin, Texas, USA). The BMC was immediately applied to a ceramic HA carrier and packed into the disc space and the interbody implant.
The 27 patients in the study had a minimum follow up of 12 months. Our purpose was to assess the clinical outcomes and the bone healing response to a porous PEEK interbody implant used a single level PLIF surgery. Advanced surface technologies in PEEK implants have demonstrated the ability to initiate and support bone healing in interbody spinal fusions. Porous PEEK is designed for osseointegration while retaining the mechanical and radiographic properties of smooth PEEK. This unique porous architecture can lead to improved outcomes for patients through the ability to initiate and support bone healing in spinal fusions. Autogenous bone grafting and the morbidities and complications associated with this second surgery can be eliminated with this advanced interbody technology. Poroussurface PEEK is a clinically viable alternative for improving clinical outcomes and the osseointegration of interbody implants in patients undergoing single-level PLIF surgery.