Sacroiliac Joint Pain and Its Treatment.

The sacroiliac joint (SIJ) as a source of symptoms has been controversial; however, as knowledge about the joint increased, its role as a pain generator in patients complaining of symptoms that are often attributed to spinal pathology has become better appreciated. The literature reports that the SIJ is the pain origin in as many as 30% of patients presenting with low back pain. Clinically, the SIJ can be challenging to evaluate; however, assessing pain location, patient posture/movement, and provocative manual testing are useful in making the presumptive diagnosis of SIJ disruption. The most definitive evaluation is image-guided injection of anesthetic solutions into the joint which is diagnostic if there is at least 75% symptom relief acutely. Treatment begins with nonoperative intervention including physical therapy and/or chiropractic care. If these fail, the next option is generally radiofrequency denervation (rhizotomy) of the joint. If this does not provide adequate relief, surgical intervention, in the form of minimally invasive SIJ fusion may be considered. The literature increasingly supports favorable results of SIJ fusion in appropriately selected patients. The purpose of this review is to provide an overview of the current literature on the SIJ, with focus on its surgical treatment.

A preliminary comparative study of radiographic results using mineralized collagen and bone marrow aspirate versus autologous bone in the same patients undergoing posterior lumbar interbody fusion with instrumented posterolateral lumbar fusion.

BACKGROUND CONTEXT: Multiple bone graft substitutes for spinal fusion have been studied with varying results. PURPOSE: The purpose of this study was to assess the effectiveness of a mineralized collagen matrix combined with bone marrow, versus autologous bone, in the same patients undergoing a posterior lumbar interbody fusion and an instrumented posterolateral lumbar fusion. STUDY DESIGN/SETTING: A prospective, comparative study. PATIENT SAMPLE: Patients indicated for one-level posterior lumbar interbody fusion and instrumented posterolateral lumbar fusion, serving as self-controls. OUTCOME MEASURES: Thin-cut computed tomographic scans with sagittal reconstruction and plain radiographs, including lateral flexion/extension views were performed and assessed at 12 and 24 months after surgery. Oswestry Disability Index and Visual Analog Scale questionnaires were completed by all patients preoperatively and at 12 and 24 months after surgery. METHODS: After informed consent and failure of nonoperative treatment, 25 consecutive patients requiring one-level instrumented posterolateral fusion combined with posterior interbody fusion were enrolled in the study. Mineralized collagen bone graft substitute combined with bone marrow aspirate was used on one side of the posterolateral fusion, with iliac crest autograft on the contralateral side. RESULTS: A fusion rate of 84% (21/25) was achieved for the autologous bone grafts and 80% (20/25) for the bone graft substitute. The interbody fusion rate was 92% (23/25). Mean Oswestry Disability Index (ODI) scores decreased 57.2% at 12 months and 55.6% at 24 months, compared with baseline. CONCLUSIONS: Mineralized collagen bone graft substitute exhibited similar radiographic results compared with autograft in this model. Further trials incorporating bilateral fusion, as well as posterolateral fusion alone without interbody fusion are warranted to confirm the results of this study.

Techniques for aspirating bone marrow for use in spinal surgery.

OBJECTIVE: The osteogenicity of bone marrow has been well documented in the literature. The use of bone marrow as a source of osteoprogenitor cells for spinal fusion surgery is increasing. Improper aspiration technique can lead to dilution of bone marrow and a subsequent reduction in osteoprogenitor cells. Therefore, correct aspiration technique is imperative to the successful use of bone marrow with various grafting combinations. METHODS: The authors describe techniques for aspirating bone marrow from the anterior and posterior iliac crest, as well as vertebral body aspiration. The use of selective cell retention to increase the number of osteoprogenitor cells populating a graft is also described. RESULTS: Complications from bone marrow aspiration can occur, but the incidence is rare. CONCLUSION: Clinical studies currently under way will answer the question of bone marrow efficacy in spinal fusion surgery.

Clinical and radiographic outcomes of anterior lumbar interbody fusion using recombinant human bone morphogenetic protein-2.

STUDY DESIGN: A prospective, nonblinded, multicenter study of outcomes in patients undergoing single-level anterior lumbar discectomy and interbody fusion with InFUSE Bone Graft. OBJECTIVE: To determine the safety and effectiveness of InFUSE Bone Graft applied to an absorbable collagen sponge in anterior lumbar interbody fusion with threaded cortical allografts. SUMMARY OF BACKGROUND DATA: In primates, InFUSE Bone Graft used with allograft dowels was shown to increase rates of interbody fusion by promoting osteoinduction and enhancing incorporation of the allograft. Recently, in a small series of human patients undergoing anterior lumbar interbody fusion with a tapered cylindrical metal fusion cage, InFUSE Bone Graft has been shown to promote osteoinduction and fusion. METHODS: Forty-six patients underwent a single-level anterior lumbar discectomy and interbody fusion at five investigational sites. They were randomly assigned to one of two groups, and the results in the investigational patients who received threaded cortical allograft dowels with InFUSE Bone Graft were compared with those in the control patients who received threaded allograft dowels with autogenous iliac crest bone graft. Patients' clinical outcomes were assessed using neurologic status, work status, and Oswestry Low Back Pain Disability, Short Form-36, and back and leg pain questionnaires. Anteroposterior, lateral, flexion-extension radiographs, and computed tomography scans were used to evaluate the progression of fusion at 6, 12, and 24 months after surgery. RESULTS: All patients who received InFUSE Bone Graft showed radiographic evidence of bony induction and early incorporation of the cortical allografts. All patients in this group had fusions at 12 months that remained fused at 24 months. At 12 and 24 months, the investigational group showed higher rates of fusion and improved neurologic status and back and leg pain when compared with the control group. There were no unanticipated adverse events related to the use of InFUSE Bone Graft. CONCLUSION: The use of InFUSE Bone Graft is a promising method of facilitating anterior intervertebral spinal fusion, decreasing pain, and improving clinical outcomes in patients who have undergone anterior lumbar fusion surgery with structural threaded cortical allograft bone dowels.