Minimally invasive surgery in adult degenerative scoliosis: a systematic review and meta-analysis of decompression, anterior/lateral and posterior lumbar approaches.

BACKGROUND: Minimally invasive approaches for the treatment of adult degenerative scoliosis have been increasingly implemented. However, little data exists regarding the safety and complication profiles of minimally invasive lumbar interbody fusion (LIF) for adult degenerative scoliosis. This study aimed to greater understand different minimally invasive surgical approaches for adult degenerative scoliosis with respect to clinical outcomes, changes in radiographic measurements, and complication profiles via meta-analytical techniques. METHODS: A systematic search of six databases from inception to September 2015 was performed by two independent reviewers. Relevant studies were those that described the safety and/or effectiveness of minimally invasive anterior or lateral LIF (LLIF), transforaminal LIF (TLIF), and decompression only. Meta-analytical techniques and meta-regression were used to pool overall rates, and compare the different techniques. There was no financial funding or conflict of interest. RESULTS: A total of 29 studies (1,228 patients) were included in this meta-analysis. Total pooled fusion rate was 95.9% (95% CI: 92.7-98.2%) for the anterior/lateral approach. The pooled construct or hardware-related complications was 4.3%, and was similar among anterior/lateral (4.4%) and posterior (5.2%) techniques. The total pooled pseudoarthrosis rate was 4.3% for the lateral approach. The overall pooled rate of motor deficit was 2.7% (95% CI: 1.7-4.0%). Subgroup meta-regression demonstrated that the anterior/lateral approach had the highest rate of motor deficits (3.6% LLIF vs. 0.7% TLIF vs. 0.5% decompression, P=0.004). The overall pooled rate of sensory deficit was 2.4%, highest for the anterior/lateral technique (3.3%) compared to TLIF (0.7%) and decompression (0.5%). The infection rate, dural tears/CSF leak, cardiac and pulmonary events were similar among the techniques, with a pooled value of 2.6%, 3.9%, 1.7%, and 1.4%, respectively. Similarly satisfactory radiological outcomes were obtained amongst the different approaches. CONCLUSIONS: Minimally invasive spine technologies may be used for the surgical treatment of lumbar degenerative scoliosis with acceptable complication rates, functional and radiological outcome. Future studies, specifically multi-centered longitudinal, examining the adequacy of minimally invasive spine surgery is warranted to compare long-term outcomes with the traditional procedure.

The role of specialist units to provide focused care and complication avoidance following traumatic spinal cord injury: a systematic review.

OBJECTIVE: Current recommendations for traumatic spinal cord injury treatment recommend immediate transfer to a spinal injury unit (SIU) where available following patient stabilisation. Although transfer is dependent on a variety of factors, the largest review was unable to justify implementation of such units on the basis of insufficient and lack of quality data in favour of care at the SIU as opposed to non-SIU centres. Our study sought to investigate: are subspecialty spinal injury units (SIUs) able to provide superior care compared with traditional trauma/rehab units? Is the standard of care of acute spinal cord injured patients to be managed in SIU's? METHOD: A literature search was conducted across five major databases using the key terms: "spinal cord injury" AND "Spinal Injury Unit" OR "spinal rehabilitation" OR "spinal injury centre" OR "specialist care" OR "care requirements." RESULTS: After review of over 500 studies, only 9 met inclusion criteria, 3 of which were past reviews. There were no relevant RCT's obtained. Standardised roles of global SIU units are needed to deliver equitable and high quality care as current evidence demonstrates variable standards of care and service (mean LOS range: 16-174 days). There is low quality evidence supporting earlier admission into SIU units being associated with improved neurological outcome, complication rates and reduced LOS, despite variations in the definition of "early admission" across studies. CONCLUSIONS: Our review demonstrates a lack of standardisation within SIU on a global scale, with significantly different outcomes reported across published studies. New and higher quality evidence directly comparing SIU to non-SIU based care is required. Earlier transfer (<24 h) to SIU following initial injury and stabilisation is advised.

PEEK-Halo effect in interbody fusion.

Recent developments have seen poly[aryl-ether-ether-ketone] (PEEK) being increasingly used in vertebral body fusion. More novel approaches to improve PEEK have included the introduction of titanium-PEEK (Ti-PEEK) composites and coatings. This paper aims to describe a potential complication of PEEK based implants relating to poorer integration with the surrounding bone, producing a "PEEK-Halo" effect which is not seen in Ti-PEEK composite implants. We present images from two patients undergoing anterior lumbar interbody fusion (ALIF). The first patient underwent an L5/S1 ALIF using a PEEK implant whilst the second patient underwent L4/L5 ALIF using a Ti-PEEK composite implant. Evidence of osseointegration was sought using CT imaging and confirmed using histological preparations of a sheep tibia model. The PEEK-Halo effect is demonstrated by a halo effect between the PEEK implant and the bone graft on CT imaging. This phenomenon is secondary to poor osseointegration of PEEK implants. The PEEK-Halo effect was not demonstrated in the second patient who received a Ti-PEEK composite graft. Histological analysis of graft/bone interface surfaces in PEEK versus Ti-PEEK implants in a sheep model further confirmed poorer osseointegration of the PEEK implant. In conclusion, the PEEK-Halo effect is seen secondary to minimal osseointegration of PEEK at the adjacent vertebral endplate following a PEEK implant insertion. This effect is not seen with Ti-PEEK implants, and may support the role of titanium in improving the bone-implant interface of PEEK substrates.

Cost-utility of minimally invasive versus open transforaminal lumbar interbody fusion: systematic review and economic evaluation.

PURPOSE: To assess the cost-utility and perioperative costs of minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) versus open-TLIF for degenerative lumbar pathologies. METHODS: Relevant articles were identified from six electronic databases. Predefined end points were extracted and meta-analysis conducted from the identified studies. RESULTS: For each study, the direct hospital cost for MI-TLIF was found to be less than that of open-TLIF. When these outcomes were pooled, direct hospital costs were found to be significantly lower in the MI-TLIF group [weighted mean difference (WMD), -$2820; I (2) = 61 %; P < 0.00001]. MI-TLIF was also associated with shorter hospitalization (WMD, 0.99; 95 % CI -1.81, -0.17; I (2) = 96 %; P = 0.02), trend toward reduced complications (relative risk 0.53; 95 % CI 0.23, 1.06; I (2) = 0 %; P = 0.07), and reduced blood loss (WMD, -246.40 mL; I (2) = 98 %; P = 0.003), but was not associated with a significant difference in operation time (WMD, -67.05; 95 % CI -169.44, 35.35; I (2) = 100 %; P = 0.20). CONCLUSIONS: From the limited evidence, the available data suggest a trend of significantly reduced perioperative costs, length of stay, and blood loss for minimally invasive compared with open surgical approaches for TLIF. MI-TLIF may represent an opportunity for optimal utilization and allocation of health-care resources from both a hospital and societal perspective.