Mid-Term and Long-Term Clinical and Radiological Outcomes of a Carbon I/F Stand-Alone Cage in Anterior Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The current study was undertaken to determine the midterm and long-term radiological outcomes, complications and functional status of patients who underwent a single-level anterior interbody lumbar fusion (ALIF) procedure. SUMMARY OF BACKGROUND DATA: Low back pain affects 70%-90% of the general population at some point in their life, and in general, the majority are best treated by nonsurgical therapy. However, a lumbar fusion can be considered in selected cases. In previous decades, lumbar interbody fusion procedures have gained popularity. Despite the approach used, stand-alone interbody fusion is becoming less popular due to poor fusion rates. When studying ALIF procedures, the addition of instrumentation results in higher fusion rates. Nevertheless, long-term follow-up can give either unexpected or similar insights into certain procedures that should be available in the current literature. Therefore, the current study was undertaken to determine the midterm and long-term radiological outcomes, complications, and functional status of patients who underwent a single-level ALIF procedure. METHODS: A cohort of 50 patients was studied following stand-alone ALIF for midterm and long-term follow-up of 6.6 years and 19.7 years, respectively. Primary outcome measurements were disability using the Oswestry Disability Index (ODI) score and pain scores using the visual analog scale, and the MOS 36-item Short-Form Health Survey (SF-36) was used to evaluate the quality of life. In addition, radiographic assessment was performed to indicate the number of solid fusions. RESULTS: After a mean of 19.7 years, we had a loss to follow-up of 34%. Functional measurements revealed an ODI of 41 for both time points and an SF-36 physical component score around 41.4 and 40.8 for the midterm and long-term follow-up, respectively. The mental component of the SF-36 was 48.7 and 49.9, respectively. The assessment of interbody fusion revealed only 66% and 70% solid fusion after 6.6 years and 19.7 years, respectively. CONCLUSIONS: In concordance with previous studies, the outcome of midterm and long-term results in this study showed that the I/F cage in ALIF procedures is a safe treatment option for single-level interbody fusion. The radiological results corroborate literature regarding stand-alone interbody fusion, and additional instrumentation is likely to increase fusion rates. However, functional measurements reveal that the postsurgical situation remains likely worse than patients in a healthy Dutch population but possibly better that in a back pain population.

Long-term results of an intensive cognitive behavioral pain management program for patients with chronic low back pain: a concise report of an extended cohort with a minimum of 5-year follow-up.

PURPOSE: Treatment options for chronic low back pain (CLBP) include cognitive behavioral interventions. Most of these interventions only have small and short-lived effects. Using strict inclusion criteria for participation in an intensive combined physical and psychological program, encouraging effects were reported at 1-year follow-up. This study evaluates the long-term follow-up results of the same program. The hypothesis is that previously reported results are maintained. METHODS: Structured interviews were conducted in a prospective extended cohort with a minimum of 5-year follow-up in a similar fashion as in the 1-year follow-up report. The median follow-up in this cohort was 6.5 years. The extended cohort consisted of 277 patients (85% response). RESULTS: Outcomes include daily functioning, quality of life, current pain intensity, pain disturbance in daily activities and indicators of the use of pain medication and healthcare services. The previously reported positive 1-year follow-up results were maintained at a minimum of 5-year follow-up. Disability as measured with the Oswestry disability index (ODIv2.1a) decreased from 40 to 27 in the first year. This positive result was maintained at the 6.5-year follow-up with an ODI of 28. Pain intensity (NRS 0-100) improved from 60 to 39 in the first year, and at 6.5 years, this had further improved to 33. Improvement in quality of life (SF 36) at 1-year follow-up was maintained at 6.5-year follow-up, and healthcare consumption had decreased substantially as measured with doctor visits and analgesics used for CLBP. CONCLUSION: Selected and motivated patients with longstanding CLBP improve fast after an intensive combined physical and psychological program in daily functioning, pain and quality of life. Positive 1-year results are maintained, and healthcare utilization was still reduced at a minimum of 5-year follow-up. These slides can be retrieved under Electronic Supplementary Material.

Relation between radiological assessment and biomechanical stability of lumbar interbody fusion in a large animal model.

PURPOSE: To relate the progress of vertebral segmental stability after interbody fusion surgery with radiological assessment of spinal fusion. METHODS: Twenty goats received double-level interbody fusion and were followed for a period of 3, 6 and 12 months. After killing, interbody fusion was assessed radiographically by two independent observers. Subsequently, the lumbar spines were subjected to four-point bending and rotational deformation, assessed with an optoelectronic 3D movement registration system. In addition, four caprine lumbar spines were analysed in both the native situation and after the insertion of a cage device, as to mimic the direct post-surgical situation. The range of motion (ROM) in flexion/extension, lateral bending and axial rotation was analysed ex vivo using a multi-segment testing system. RESULTS: Significant reduction in ROM in the operated segments was already achieved with moderate bone ingrowth in flexion/extension (71 % reduction in ROM) and with only limited bone ingrowth in lateral bending (71 % reduction in ROM) compared to the post-surgical situation. The presence of a sentinel sign always resulted in a stable vertebral segment in both flexion/extension and lateral bending. For axial rotation, the ROM was already limited in both native and cage inserted situations, resulting in non-significant differences for all radiographic scores. DISCUSSION: In vivo vertebral segment stability, defined as a significant reduction in ROM, is achieved in an early stage of spinal fusion, well before a radiological bony fusion between the vertebrae can be observed. Therefore, plain radiography underestimates vertebral segment stability.

The effect of ethylene oxide, glow discharge and electron beam on the surface characteristics of poly(L-lactide-co-caprolactone) and the corresponding cellular response of adipose stem cells.

Bioabsorbable polymers are increasingly being used in tissue engineering strategies. Despite the knowledge that some sterilization techniques may affect the physical properties of these polymers, this aspect is often overlooked. We speculate that the type of sterilization method used may influence cellular responses by altering the surface characteristics. We cultured adipose stem cells on bioabsorbable poly(l-lactide-co-caprolactone) (PLCL) sheets, sterilized using either ethylene oxide (EO), argon glow discharge (aGD) or electron beam (e-beam). Significantly higher values for surface roughness in the order EO>aGD>e-beam and significant differences in contact angles (EO>e-beam>aGD) and surface energies (aGD>e-beam>EO) were observed. Increased cell attachment and proliferation rates were observed with lower contact angles. The alkaline phosphatase activity was significantly higher for the ethylene oxide sterilized PLCL sheet. In conclusion, the type of sterilization for bioabsorbable polymers should be considered in the design of new scaffolds, since it might affect, or can be used to enhance, the outcome of the tissue engineered construct.

Adipose stem cells for intervertebral disc regeneration: current status and concepts for the future.

New regenerative treatment strategies are being developed for intervertebral disc degeneration of which the implantation of various cell types is promising. All cell types used so far require in vitro expansion prior to clinical use, as these cells are only limited available. Adipose-tissue is an abundant, expendable and easily accessible source of mesenchymal stem cells. The use of these cells therefore eliminates the need for in vitro expansion and subsequently one-step regenerative treatment strategies can be developed. Our group envisioned, described and evaluated such a one-step procedure for spinal fusion in the goat model. In this review, we summarize the current status of cell-based treatments for intervertebral disc degeneration and identify the additional research needed before adipose-derived mesenchymal stem cells can be evaluated in a one-step procedure for regenerative treatment of the intervertebral disc. We address the selection of stem cells from the stromal vascular fraction, the specific triggers needed for cell differentiation and potential suitable scaffolds. Although many factors need to be studied in more detail, potential application of a one-step procedure for intervertebral disc regeneration seems realistic.