Kelley Banagan

Anatomic mapping of lumbar nerve roots during a direct lateral transpsoas approach to the spine: a cadaveric study.

Study Design. Cadaveric study. Objective. Identifying anatomic structures at risk for injury during direct lateral transpsoas approach to the spine. Summary of Background Data. Direct lateral transpsoas approach is a novel technique that has been described for anterior lumbar interbody fusion. Potential risks include damage to genitofemoral nerve and lumbar plexus, which are not well visualized during small retroperitoneal exposure. Previous cadaveric studies did not evaluate the direct lateral transpsoas approach, and considering the approach being used in clinical practice, the current study was undertaken in an effort to identify the structures at risk during direct lateral transpsoas approach. Methods. Sixteen dissections were performed on eight fresh-frozen male cadavers. Eight were to localize proximal lumbar nerve roots, ilioinguinal nerves, and genitofemoral nerves and establish their relationship to psoas muscle and disc space. Four simulated direct lateral transpsoas approaches, with K-wire placed into mid-disc space under fluoroscopic guidance, were made. In four dissections, sequential dilators were inserted, disc space was evacuated, and interbody devices were placed. The study was conducted in three phases to identify, in a stepwise progression, which portion of the procedure placed the nerve at greatest risk. Results. With initial dissections, perforating branches of lumbar nerve roots were identified in anterior, middle, and posterior third of psoas muscle. Sympathetic chain was identified in anterior third of psoas over L1–L4. Distance from the middle of the anterior longitudinal ligament at the level of the disc to the sympathetic chain averaged 9.25 mm. The nerve roots and genitofemoral nerve were placed at risk in all dissections in which the approach was recreated. Damage secondary to K-wire placement occurred in 25% of cases at L3–L4 and L4–L5; in one case, L4 nerve root was pierced, and in another, genitofemoral nerve was pierced. K-wire was posterior to the nerve roots in 25% of cases at L3–L4 and in 50% of cases at L4–L5. The lumbar plexus was placed under tension because of sequential dilator placement. Conclusion. On the basis of our results, there is no zone of absolute safety when using the direct lateral transpsoas approach. The potential for nerve injury exists when using this approach, and consequently, we recommend either direct visualization of the nerve roots intraoperatively and/or the use of neuromonitoring. In our opinion, a higher quality, larger clinical study that examines the outcomes and surgical complications of the direct lateral transpsoas approach is warranted.

Magnetic resonance imaging for the evaluation of ligamentous injury in the pelvis: A prospective case-controlled study

Objectives: Management of external rotation pelvic ring disruptions is based on which ligaments are disrupted within the pelvis. We hypothesized that magnetic resonance imaging (MRI) can evaluate the ligaments of the pelvic ring and differentiate injured from uninjured pelves. Design: Prospective cohort study. Setting: Level I trauma center. Patients: Twenty-one patients with 25 acute external rotation injuries of the hemipelvis; control group of 26 patients without pelvic ring injury. Intervention: All patients underwent the same MRI protocol reviewed by 1 musculoskeletal radiologist. Main Outcome Measures: Integrity of 5 structures: sacrospinous, sacrotuberous, anterior sacroiliac, and posterior sacroiliac ligaments and pelvic floor musculature. Results: Visualization of sacrospinous, sacrotuberous, anterior sacroiliac, and posterior sacroiliac ligaments, and pelvic floor musculature was possible for 91%, 100%, 98%, 91%, and 100%, respectively, of all studied structures. No injuries were identified in control group patients in contrast to ligament injury observed with all injured pelves (0% versus 100%; P < 0.0001). Observed relationship of ligament injury to pelvic injury type generally agreed with the Young–Burgess classification system, with the important exception that patients with anterior–posterior compression type II injuries had damage to the sacrospinous ligament in only 50% of the cases. Conclusions: Ligamentous anatomy and injury about the pelvic ring appears to be easily evaluated with MRI, arguing that there may be a role for this imaging modality in managing these cases. Tearing of the sacrospinous ligament is variable among anterior–posterior compression type II injuries, arguing that the injury pattern can be subdivided into those with and without sacrospinous ligament tears. Level of Evidence: Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Outcomes of lumbopelvic fixation in the treatment of complex sacral fractures using minimally invasive surgical techniques

BACKGROUND CONTEXT Complex sacral fractures with vertical and anterior pelvic ring instability treated with traditional fixation methods are associated with high rates of failure and poor clinical outcomes. Supplemental lumbopelvic fixation (LPF) has been applied for additional stability to help with fracture union. PURPOSE The study aimed to determine whether minimally invasive LPF provides reliable fracture stability and acceptable complication rates in cases of complex sacral fractures. STUDY DESIGN/SETTING This is a retrospective cohort study at a single level I trauma center. PATIENT SAMPLE The sample includes 24 patients who underwent minimally invasive LPF for complex sacral fracture with or without associated pelvic ring injury. OUTCOME MEASURES Reoperation for all causes, loss of fixation, surgical time, transfusion requirements, length of hospital stay, postoperative day at mobilization, and mortality were evaluated. METHODS Patient charts from 2008 to 2014 were reviewed. Of the 32 patients who underwent minimally invasive LPF for complex sacral fractures, 24 (12 male, 12 female) met all inclusion and exclusion criteria. Outcome measures were assessed with a retrospective chart review and radiographic review. The authors did not receive external funding for this study. RESULTS Acute reoperation was 12%, and elective reoperation was 29%. Two (8%) patients returned to the operating room for infection, one (4.2%) required revision for instrumentation malposition, and seven (29%) underwent elective removal of instrumentation. No patient experienced failure of instrumentation or loss of correction. Average surgical time was 3.6 hours, blood loss was 180 mL, transfusion requirement was 2.1 units of packed red blood cells, and postoperative mobilization was on postoperative day 5. No mortalities occurred as a result of the minimally invasive LPF procedure. CONCLUSIONS Compared with historic reports of open LPF, our results demonstrate reliable maintenance of reduction and acceptable complication rates with minimally invasive LPF for complexsacral fractures. The benefits of minimally invasive LPF may be offset with increased elective reoperations for removal of instrumentation.

Low-Density Pedicle Screw Constructs for Adolescent Idiopathic Scoliosis: Evaluation of Effectiveness and Cost:

Introduction Optimal screw density and technique in treatment of idiopathic scoliosis remain unknown. We sought to find if low-density (LD) screw construct can achieve curve correction similar to that achieved with high-density (HD) constructs in adolescent scoliosis at substantial cost savings. Materials and Methods Patients treated operatively for idiopathic scoliosis at our center between 2007 and 2011 were identified through a retrospective database review. Each patient was treated with an LD screw construct. Radiographic outcomes included assessment of screw density, percent correction of major and fractional lumbar curves at follow-up, T5−T12 kyphosis, and angle of lowest instrumented vertebra (LIV). Costs were calculated and compared with costs of HD constructs. Results Forty-five patients met inclusion criteria. Ages ranged from 12 to 19 years (mean age, 14.9 years). Average construct density was 1.2 screws per fused level (range, 1.07−1.33 screws). Mean percent curve correction at latest follow-up: major curve, 67.2%; fractional lumbar curve, 69%. Average postoperative thoracic kyphosis: 30 degrees. Mean LIV angle: 5.6 degrees. Total screw cost was

Minimally Invasive Thoracolumbar Facet Joint Fusion

13,370 per case in the LD group compared with

Outcomes of Multilevel Vertebrectomy for Spondylodiscitis

22,340 per case if all levels had been instrumented with 2 screws. Conclusions Our LD screw construct is among the lowest density constructs reported in the literature and achieves curve correction comparable to that reported for HD constructs at substantially lower cost.

Can Liposomal Bupivacaine Be Safely Utilized in Elective Spine Surgery

For minimally invasive spine surgery to be successful, it is mandatory that it achieves the same goals that open surgical procedures achieve. By avoiding collateral damages to anatomic structures, the purported advantages of minimally invasive techniques include reduction in postoperative pain, length of hospitalization, blood loss, and medical and surgical complications. During the past several years, surgeons have been expanding the indications for minimally invasive techniques from degenerative procedures to more complex spinal disorders, including thoracolumbar deformity, trauma, tumor, and infections. Paramount to successful results of treatment of many thoracolumbar pathological conditions is achieving a solid biological fusion.

Minimally Invasive Lateral Spine Surgery in Trauma

BACKGROUND CONTEXT The incidence of pyogenic vertebral osteomyelitis (PVO) continues to increase in the United States, highlighting the need to recognize unique challenges presented by these cases and develop effective methods of surgical management. To date, no prior research has focused on the outcomes of PVO requiring two or more contiguous corpectomies. PURPOSE To describe our experience in the operative management of PVO in 56 consecutive patients who underwent multilevel corpectomies (≥2 vertebral bodies) via a combined approach. STUDY DESIGN/SETTING Single institution retrospective cohort review between January 2002 and December 2015. All patients had been treated at an academic tertiary referral center by one of two fellowship-trained orthopedic spine surgeons. PATIENT SAMPLE Patient records were cross-referenced with International Classification of Diseases osteomyelitis codes and paravertebral abscess code. Inclusion criteria for the study were patients within the cohort who had adequate medical records for review, a minimum patient age of 18 years, active vertebral osteomyelitis as an indication for surgical intervention, a minimum of 1-year radiographic follow-up, and surgical intervention that included at least two complete vertebral corpectomies. Subsequently, 56 patients met the inclusion criteria and were reviewed for this retrospective analysis. OUTCOME MEASURES Outcomes of interest were readmission and reoperation rates related to treatment of PVO, 30-day and 1-year mortality rates, radiographic outcomes, perioperative complications, infection control, and length of stay. METHODS After obtaining approval from the Institutional Review Board, retrospective review was performed on records of all adults with PVO refractory to standard nonoperative treatment who underwent complete corpectomy of two or more contiguous vertebrae at a single institution between January 2002 and December 2015. This study was not funded, and no potential conflict of interest-associated biases were present. RESULTS Fifty-six patients were identified (63% men; mean age 56.8 years; mean radiographic follow-up 2.8 years). Median length of stay was 13 days with nearly half readmitted (47%) after a median of 222.5 days after surgery. Twelve (22%) posterior revisions were required after a median 54 days for infection, painful or failed hardware, proximal junction kyphosis, adjacent level disease, or extension of the fusion. Thirty-day and 1-year mortality rates were 7.14% and 19.6%, respectively, with an infectious etiology as the most common cause of death. CONCLUSIONS Multilevel vertebral corpectomy for treatment of refractory vertebral osteomyelitis is associated with relatively high rates of complications and mortality compared with historical controls for 1 or 2 level procedures. We found clinical resolution and absence of complications requiring return to the operating room in 75% of patients when complete extirpation of the involved vertebrae is achieved. Our findings suggest multilevel anterior corpectomies with posterior stabilization may be a reasonable surgical option when approaching patients with complicated spondylodiscitis.

Management of Traumatic Spondylolisthesis: Cervical and Lumbar

Study Design: Single-blinded prospective randomized control trial. Objectives: To compare the incidence of adverse events (AEs) and hospital length of stay between patients who received liposomal bupivacaine (LB) versus a single saline injection, following posterior lumbar decompression and fusion surgery for degenerative spondylosis. Methods: From 2015 to 2016, 59 patients undergoing posterior lumbar decompression and fusion surgery were prospectively enrolled and randomized to receive either 60 mL injection of 266 mg LB or 60 mL of 0.9% sterile saline, intraoperatively. Outcome measures included the incidence of postoperative AEs and hospital length of stay. Results: The most common AEs in the treatment group were nausea (39.3%), emesis (18.1%), and hypotension (18.1%). Nausea (23%), constipation (19.2%), and urinary retention (15.3%) were most common in the control group. Patients who received LB had an increased risk of developing nausea (relative risk [RR] = 1.7; 95% confidence interval [CI] = 0.75-3.8), emesis (RR = 2.3; 95% CI = 0.51-10.7), and headaches (RR = 2.36; 95% CI = 0.26-21.4). Patients receiving LB had a decreased risk of developing constipation (RR = 0.78; 95% CI = 0.25-2.43), urinary retention (RR = 0.78; 95% CI = 0.21-2.85), and pruritus (RR = 0.78; 95% = 0.21-2.8) postoperatively. Relative risk values mentioned above failed to reach statistical significance. No significant difference in the hospital length of stay between both groups was found (3.9 vs 3.9 days; P = .92). Conclusion: Single-dose injections of LB to the surgical site prior to wound closure did not significantly increase or decrease the incidence or risk of developing AEs postoperatively. Furthermore, no significant difference was found in the hospital length of stay between both groups.

Thoracolumbar Spine Trauma

Thoracolumbar trauma patients present unique challenges to the spine surgeon, whose goals are to prevent primary or secondary neurological injury, enhance neurological recovery, stabilize the spine to promote early mobilization, and minimize surgical morbidity. Minimally invasive surgery (MIS) has become a key tool in the spine surgeon’s armamentarium in the treatment of these potentially fragile patients, as it affords an alternative to traditional open procedures and their associated increased blood loss and infection rates [1, 2]. Specifically, lateral minimally invasive spine surgery (MISS) has recently become a treatment option in this patient population. The development of minimally invasive techniques potentially allows surgeons to better treat spine trauma patients by providing early decompression or stabilization while minimizing the morbidity of surgery. In this chapter, the epidemiology of thoracolumbar spinal cord injuries will be discussed, followed by the indications for the use of lateral MISS procedures versus the conventional open anterior approaches. The surgical technique for lateral MISS will be outlined, as well as the pros and cons of this approach. Finally, a case example will detail the use of lateral MISS in clinical practice.