Percutaneous Transpedicular Fixation: Technical tips and Pitfalls of Sextant and Pathfinder Systems

STUDY DESIGN: The efficacy of the operative techniques, possible benefits as well as pitfalls and limitations of the techniques are discussed. Potential drawbacks are also detected. PURPOSE: This study aims to report indications, techniques, and our experience with the use of the Sextant and PathFinder percutaneous transpedicular screw fixation systems. OVERVIEW OF LITERATURE: Percutaneous pedicle screw insertion is a novel technique. Successful percutaneous placement of pedicle screws requires surgical skill and experience because of lack of anatomic surface landmarks. Fluoroscopy-guided percutaneous placement of pedicle screws is effective. Many systems are now available. METHODS: We conducted a prospective operative and postoperative analysis of 40 patients with absolute indication for thoracic or lumbar instability between January 2009 and June 2013. All procedures were performed with the Sextant (group A) and PathFinder (group B) systems under fluoroscopic guidance. Operative techniques are discussed and the results compared. RESULTS: Percutaneous transpedicular screw fixation minimizes the morbidity associated with open techniques without compromising the quality of fixation. A total of 190 screws were inserted. There was no additional morbidity. Postoperative computed tomography images and plain X-rays were analyzed. Reduction of visual analog scale scores of back pain was evident. CONCLUSIONS: Fluoroscopy-guided percutaneous pedicular screws are feasible and can be safely done. Current systems allow multi-segmental fixation with significantly less difficulties. The described techniques have acceptable intra- and postoperative complication rates, and overall sufficient pain control with early mobilization of patients.

Safety and Efficacy of Mini Open Transforaminal Lumbar Interbody Fusion

OBJECTIVE: Mini-transforaminal lumbar interbody fusion (Mini-TLIF) and other minimally invasive approaches introduced for the purpose of treating lumbar degenerative disc disease and instability are achieving high success and safety rates as the conventional approaches. Moreover, it has less soft tissue damage, minimal blood loss, and less hospital stay. METHODS: A prospective study was conducted from 2012 to 2014 on 28 patients who were subjected to Mini-open TLIF combined with transpedicular screw fixation for spondylolisthesis and degenerative disc disease. Two paramedian approaches were done, 4 cm for each, to insert the pedicular screws, along with inserting unilateral TLIF cage with autologous bone graft. Decompression was done either unilateral or bilateral according to the patient side of radiculopathy. Sixteen patients (57.2%) were diagnosed with degenerative spondylolisthesis, 7 patients (25%) were diagnosed with isthmic type spondylolisthesis, and 5 patients (17.8%) were diagnosed with degenerative disc disease, 2 of them(7.1%) had previous operations at the same level. Twenty patients (71.4%) were operated at the L4/5 level, and 8 patients (28.6%) at the L5/S1 level. RESULTS: All patients were able to ambulate the next day of surgery. The mean estimated blood loss was 251.79mL. The average hospital stay was 4.14 days. The average follow-up was 9 months. The mean visual analog scale was 1.86 at discharge, 1.68 after 3 months, and 1.38 after 6 months. After 6 months of the operation, MacNab's criteria were good in 23 patients and excellent in 5 patients. We had one case with transient weakness, 2 cases of screw malposition without clinical manifestations, and one case of infection. CONCLUSION: Mini-TLIF approach is an efficient and safe approach for treating instability and degenerative diseases of the lumbar spine. The clinical outcome is encouraging and it may be an operation of choice for lumbar spinal fusion in selected patients.

Epidural Fibrosis after Lumbar Disc Surgery: Prevention and Outcome Evaluation

STUDY DESIGN: This is a prospective, randomized, controlled study designed and conducted over 10 years from 2002 to 2012. PURPOSE: The study aimed to monitor the effect of suction drains (SD) on the incidence of epidural fibrosis (EF) and to test, if the use of SD alone, SD with local steroids application, SD combined with fat grafts and local steroids application, or SD combined with fat grafts and without local steroids application, would improve outcome. OVERVIEW OF LITERATURE: EF contributes to significant unsatisfactory failed-back syndrome. Efforts have been tried to reduce postoperative EF, but none were ideal. METHODS: Between September 2002 and 2012, 290 patients with symptomatic unilateral or bilateral, single-level lumbar disc herniation were included in the study. Two groups were included, with 165 patients in group I (intervention group) and 125 patients in group II (control group). Group I was subdivided into four subgroups: group Ia (SD alone), group Ib (SD+fat graft), group Ic (SD+local steroids), and group Id (SD+fat graft+local steroids). RESULTS: The use of SD alone or combined with only fat grafts, fats grafts and local steroids application, or only local steroids application significantly improved patient outcome and significantly reduced EF as measured by magnetic resonance imaging (MRI). CONCLUSIONS: This study has clearly demonstrated the fact that the use of suction drainage alone or combined with only fat grafts, fats grafts and local steroids application, or only local steroids application significantly improved patient outcome with respect to pain relief and functional outcome and significantly reduced EF as measured by an MRI. A simple grading system of EF on MRI was described.

Cervical Pedicle Screw Fixation: Anatomic Feasibility of Pedicle Morphology and Radiologic Evaluation of the Anatomical Measurements

STUDY DESIGN: All parameters were measured manually and with a computed tomography (CT) scanner. For the manual measurements, a Vernier scale instrument was used. PURPOSE: This study evaluates quantitatively pedicles of middle and lower cervical spine (C3 to C7) and to evaluate the possibilities of using these structures as anchors in posterior cervical fusion. OVERVIEW OF LITERATURE: Pedicle screws may be an alternative fixation technique for posterior cervical instrumentation. METHODS: Twenty-two bony sets of adult cervical spines were studied (110 vertebrae, 220 pedicles) from C3 down to C7. RESULTS: CT measurement of cervical pedicles appeared to be accurate and valuable for preoperative planning of cervical pedicle screw instrumentation. The study showed a high correlation between the values obtained by manual and CT measurements of pedicle dimensions. The technical challenge of insertion is the obvious theoretical drawback of the use of cervical pedicle screws. Many technical factors are important to consider, namely, the point of screw entry, the pedicle dimensions, the screw direction according to the pedicle angle and orientation, the screw diameter and length, and the method of screw introduction. CONCLUSIONS: Transpedicular screw fixation of the cervical spine appears to be promising. Anatomic limitations should be clear to the surgeon. Further clinical and biomechanical studies are needed to settle this technique.

Lumbar Transpedicular Implant Failure: A Clinical and Surgical Challenge and Its Radiological Assessment

STUDY DESIGN: It is a multicenter, controlled case study review of a big scale of pedicle-screw procedures from January 2000 to June 2010. The outcomes were compared to those with no implant failure. PURPOSE: The purpose of this study was to review retrospectively the outcome of 100 patients with implant failure in comparison to 100 control-patients, and to study the causes of failure and its prevention. OVERVIEW OF LITERATURE: Transpedicular fixation is associated with risks of hardware failure, such as screw/rod breakage and/or loosening at the screw-rod interface and difficulties in the system assembly, which remain a significant clinical problem. Removal or revision of the spinal hardware is often required. METHODS: Two hundred patients (88 women, 112 men) were divided into 2 major groups, with 100 patients in group I (implant failure group G1) and 100 patients in group II (successful fusion, control group G2). We subdivided the study groups into two subgroups: subgroup a (single-level instrumented group) and subgroup b (multilevel instrumented group). The implant status was assessed based on intraoperative and follow-up radiographs. RESULTS: Implant failure in general was present in 36% in G1a, and in 64% in G1b, and types of implant failure included screw fracture (34%), rod fracture (24%), rod loosening (22%), screw loosening (16%), and failure of both rod and screw (4%). Most of the failures (90%) occurred within 6 months after surgery, with no reported cases 1 year postoperatively. CONCLUSIONS: We tried to address the problem and study the causes of failure, and proposed solutions for its prevention.