Jarred Hogan

Cortical Bone Trajectory for Lumbar Pedicle Screw Placement: A Review of Published Reports

There have been a number of developments in screw design and implantation techniques over recent years, including proposal of an alternative trajectory for screw fixation aimed at increasing purchase of pedicle screws in higher density bone. Cortical bone trajectory (CBT) screw insertion follows a lateral path in the transverse plane and caudocephalad path in the sagittal plane. This technique has been advocated because it is reportedly less invasive, improves screw−bone purchase and reduces neurovascular injury; however, these claims have not been supported by robust clinical evidence. The available evidence was therefore reviewed to assess the relative merits of CBT and highlight areas for further research. To this end, a search of relevant published studies reporting biomechanical, morphometric or clinical outcomes after use of CBT screws in patients with spinal pathologies was performed via six electronic databases.

Anterior cervical disc arthroplasty (ACDA) versus anterior cervical discectomy and fusion (ACDF): a systematic review and metaanalysis

BACKGROUND Surgical approaches are usually required in cases of severe cervical disc disease. The traditional method of anterior cervical disc fusion (ACDF) has been associated with reduced local mobility and increased occurrence of adjacent segment disease. The newer method of anterior cervical disc arthroplasty (ACDA) relies upon artificial discs of various products. Current literature is inconsistent in the comparative performance of these methods with regards to clinical, radiological and patient outcomes. METHODS Electronic databases, including OVID Medline, PubMed, Scopus, Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews, were comprehensively searched to retrieve studies comparing the treatment outcomes of ACDF and ACDA. Baseline characteristics and outcome data were extracted from eligible articles. RESULTS Two hundred and fifty five articles were identified through the database searches, and after screening 28 studies were included in the systematic review and meta-analysis. A total of 4,070 patients were included (2156 ACDA, 1914 ACDF). There was no significant difference between the two groups in operation time, blood loss during operation, long-term all-complication rate and reoperation rate at the level of injury. The ACDA group had significantly better neurological outcomes, as well as a significantly lower rate of adjacent segment diseases. CONCLUSIONS Compared with ACDF, the ACDA procedure is associated with improved reoperation rate and reduction in neurological deficits amongst previously demonstrated benefits. There is heterogeneity in ACDA devices; future studies are required to investigate the impact of this technique on treatment outcomes.

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.