Minimally invasive versus open transforaminal lumbar interbody fusion for treatment of degenerative lumbar disease: systematic review and meta-analysis.

PURPOSE: While open TLIF (O-TLIF) remains the mainstay approach, minimally invasive TLIF (MI-TLIF) may offer potential advantages of reduced trauma to paraspinal muscles, minimized perioperative blood loss, quicker recovery and reduced risk of infection at surgical sites. This meta-analysis was conducted to provide an updated assessment of the relative benefits and risks of MI-TLIF versus O-TLIF. METHODS: Electronic searches were performed using six databases from their inception to December 2014. Relevant studies comparing MI-TLIF and O-TLIF were included. Data were extracted and analysed according to predefined clinical end points. RESULTS: There was no significant difference in operation time noted between MI-TLIF and O-TLIF cohorts. The median intraoperative blood loss for MI-TLIF was significantly lower than O-TLIF (median: 177 vs 461 mL; (weighted mean difference) WMD, -256.23; 95% CI -351.35, -161.1; P < 0.00001). Infection rates were significantly lower in the minimally invasive cohort (1.2 vs 4.6%; relative risk (RR), 0.27; 95%, 0.14, 0.53; I2) = 0%; P = 0.0001). VAS back pain scores were significantly lower in the MI-TLIF group compared to O-TLIF (WMD, -0.41; 95% CI -0.76, -0.06; I2 = 96%; P < 0.00001). Postoperative ODI scores were also significantly lower in the minimally invasive cohort (WMD, -2.21; 95% CI -4.26, -0.15; I2 = 93%; P = 0.04). CONCLUSIONS: In summary, the present systematic review and meta-analysis demonstrated that MI-TLIF appears to be a safe and efficacious approach compared to O-TLIF. MI-TLIF is associated with lower blood loss and infection rates in patients, albeit at the risk of higher radiation exposure for the surgical team. The long-term relative merits require further validation in prospective, randomized studies.

Posterior stabilization at the cervicothoracic junction: a biomechanical study.

STUDY DESIGN: This study biomechanically evaluated three fixation devices for stability with posterior two- and three-column injuries. OBJECTIVES: To find an effective means of posteriorly stabilizing injuries at the cervicothoracic junction. SUMMARY OF BACKGROUND DATA: The cervicothoracic spine is complex anatomically and has been a difficult challenge in approach and stabilization of traumatic and degenerative disorders. METHODS: Twenty-one human cadaveric spines (C3-T3) were loaded in flexion, extension, lateral bending, and axial torsion. A posterior two-column injury was created at C7-T1. One of three posterior fixation systems was applied (two rod-screw systems, one plate-screw system, all with screws at C5, C6 and T1, T2). The spines were tested again. A three-column injury was created by transecting the remaining anterior structures; the spines were tested a final time. RESULTS: In flexion-extension, there were no significant differences in stiffness between intact and instrumented two-column injury specimens for all systems; the instrumented three-column injury was significantly (P < 0.05) less stiff than intact specimens in extension. Ranges of motion and neutral zones decreased from intact to instrumented two-column injuries and increased from intact to three-column constructs. In lateral bending and axial rotation, all systems were stiffer than intact spines for both injuries; ranges of motion and neutral zones were reduced for both injuries compared with intact specimens. CONCLUSION: All three systems stabilize the cervicothoracic junction with a posterior two-column injury in flexion-extension, lateral bending, and axial rotation; none was adequate for a three-column injury, particularly in extension. A three-column injury at this level would warrant supplemental anterior fixation.

History of minimally invasive spine surgery.

Patients prefer minimally invasive techniques because such techniques reduce recovery times and provide cosmetic benefits. Reviewing the history of minimally invasive surgery helps us understand the advances in spine surgery. Minimally invasive spine surgery has adopted techniques from several fields to better treat spinal disorders. Minimally invasive spine surgery has been influenced by advances in lasers, endoscopy, and image guidance systems. Discogenic disorders have been treated by using chemonucleolysis, automated percutaneous discectomy, and intradiscal thermoablation. Endoscopic techniques have been used to treat spinal disorders. Thoracoscopes and laparoscopes have been used to perform anterior release of scoliotic or kyphotic deformities and to perform transthoracic microsurgical discectomies. The role of spinal thoracoscopy has expanded to include corpectomy, vertebral reconstruction with internal fixation, hardware application, and resection of neurogenic, spinal, and paraspinal tumors. Advances in interbody fusion cage technology have generated a great deal of interest in laparoscopic techniques. Image-guided systems are widely used in intracranial surgery and have been adapted to facilitate screw placement since the middle 1990s. The use of image-guided systems for pedicle screw placement has improved placement accuracy. The system relies on precise localization of the pedicles with computed tomography. Minimally invasive surgery is designed for "conventional" operations involving extensive anatomic dissections performed via small incisions; it yields shorter recovery times and less morbidity.

Minimally invasive spine instrumentation.

OBJECTIVE: We discuss the instrumentation used with minimally invasive spine surgery. METHODS: Minimally invasive surgery has revolutionized all areas of surgery. The use of endoscopes permits surgical maneuvers to be performed through small incisions. RESULTS: Video-assisted thoracoscopic surgery can be used for a variety of spinal indications. The nerve roots and the spinal cord can be decompressed, bone grafts can be placed for interbody fusion and vertebral body reconstruction, and internal fixation devices can be applied to stabilize the spine. Thoracoscopy can be used to perform thoracic sympathectomies, to resect thoracic disk herniations, to biopsy thoracic vertebral body lesions, to release complex spinal curvatures for the reduction of scoliosis, to perform vertebrectomies, to resect tumors, to debride infections, and to treat spinal fractures. Laparoscopic techniques have been applied to the lumbar spine. Laparoscopic procedures have been used for anterior and posterior approaches to the lumbar spine. Anterior arthrodesis has been performed by laparoscopic insertion of the Bagby and Kuslich cages into the L4-5 and the L5-S1 intervertebral disc spaces. Laparoscopic retroperitoneal techniques have been used for anterior plating to fixate the anterior column rigidly to restore stability. In addition, the posterolateral approach has been used for pedicle screw fixation of the lumbar spine using endoscopic techniques. CONCLUSION: Minimally invasive techniques have been used successfully for treating spinal disorders. With the use of endoscopic techniques, a spine surgeon can perform complex spinal instrumentation through small portals, thus reducing morbidity for the patient.