E. Lee Nelson

Minimally invasive versus open transforaminal lumbar interbody fusion

Background Available clinical data are insufficient for comparing minimally invasive (MI) and open approaches for transforaminal lumbar interbody fusion (TLIF). To date, a paucity of literature exists directly comparing minimally invasive (MI) and open approaches for transforaminal lumbar interbody fusion (TLIF). The purpose of this study was to directly compare safety and effectiveness for these two surgical approaches. Materials and Methods Open or minimally invasive TLIF was performed in 63 and 76 patients, respectively. All consecutive minimally invasive TLIF cases were matched with a comparable cohort of open TLIF cases using three variables: diagnosis, number of spinal levels, and history of previous lumbar surgery. Patients were treated for painful degenerative disc disease with or without disc herniation, spondylolisthesis, and/or stenosis at one or two spinal levels. Clinical outcome (self-report measures, e.g., visual analog scale (VAS), patient satisfaction, and MacNabs criteria), operative data (operative time, estimated blood loss), length of hospitalization, and complications were assessed. Average follow-up for patients was 37.5 months. Results: The mean change in VAS scores postoperatively was greater (5.2 vs. 4.1) in theopen TLIF patient group (P = 0.3). MacNabs criteria score was excellent/good in 67% and 70% (P = 0.8) of patients in open and minimally invasive TLIF groups, respectively. The overall patient satisfaction was 72.1% and 64.5% (P = 0.4) in open and minimally invasive TLIF groups, respectively. The total mean operative time was 214.9 min for open and 222.5 min for minimally invasive TLIF procedures (P = 0.5). The mean estimated blood loss for minimally invasive TLIF (163.0 ml) was significantly lower (P < 0.0001) than the open approach (366.8 ml). The mean duration of hospitalization in the minimally invasive TLIF (3 days) was significantly shorter (P = 0.02) than the open group (4.2 days). The total rate of neurological deficit was 10.5% in the minimally invasive TLIF group compared to 1.6% in the open group (P = 0.02). Conclusions: Minimally invasive TLIF technique may provide equivalent long-term clinical outcomes compared to open TLIF approach in select population of patients. The potential benefit of minimized tissue disruption, reduced blood loss, and length of hospitalization must be weighted against the increased rate of neural injury-related complications associated with a learning curve.

The accuracy of pedicle screw placement using intraoperative image guidance systems

OBJECT Several retrospective studies have demonstrated higher accuracy rates and increased safety for navigated pedicle screw placement than for free-hand techniques; however, the accuracy differences between navigation systems has not been extensively studied. In some instances, 3D fluoroscopic navigation methods have been reported to not be more accurate than 2D navigation methods for pedicle screw placement. The authors of this study endeavored to identify if 3D fluoroscopic navigation methods resulted in a higher placement accuracy of pedicle screws. METHODS A systematic analysis was conducted to examine pedicle screw insertion accuracy based on the use of 2D, 3D, and conventional fluoroscopic image guidance systems. A PubMed and MEDLINE database search was conducted to review the published literature that focused on the accuracy of pedicle screw placement using intraoperative, real-time fluoroscopic image guidance in spine fusion surgeries. The pedicle screw accuracy rates were segregated according to spinal level because each spinal region has individual anatomical and morphological variations. Descriptive statistics were used to compare the pedicle screw insertion accuracy rate differences among the navigation methods. RESULTS A total of 30 studies were included in the analysis. The data were abstracted and analyzed for the following groups: 12 data sets that used conventional fluoroscopy, 8 data sets that used 2D fluoroscopic navigation, and 20 data sets that used 3D fluoroscopic navigation. These studies included 1973 patients in whom 9310 pedicle screws were inserted. With conventional fluoroscopy, 2532 of 3719 screws were inserted accurately (68.1% accuracy); with 2D fluoroscopic navigation, 1031 of 1223 screws were inserted accurately (84.3% accuracy); and with 3D fluoroscopic navigation, 4170 of 4368 screws were inserted accurately (95.5% accuracy). The accuracy rates when 3D was compared with 2D fluoroscopic navigation were also consistently higher throughout all individual spinal levels. CONCLUSIONS Three-dimensional fluoroscopic image guidance systems demonstrated a significantly higher pedicle screw placement accuracy than conventional fluoroscopy or 2D fluoroscopic image guidance methods.

Prospective, Randomized, Double-Blind Clinical Study Evaluating the Correlation of Clinical Outcomes and Cervical Sagittal Alignment

BACKGROUND:Sagittal alignment of the cervical spine has received increased attention in the literature as an important determinant of clinical outcomes after anterior cervical diskectomy and fusion. Surgeons use parallel or lordotically fashioned grafts depending on preference or simple availability. OBJECTIVE:To quantitatively assess and compare cervical sagittal alignment and clinical outcome when lordotic or parallel allografts were used for fusion. METHODS:A prospective, randomized, double-blind clinical study that enrolled 122 patients was performed. The mean follow-up was 37.5 months (range, 12-54 months). RESULTS:The mean postoperative cervical sagittal alignment was 19° (range, −7°-36°) and 18° (range, −7°-37°) in the lordotic and parallel graft patient groups, respectively. The mean segmental sagittal alignment was 6° (range, −4°-19°) and 7° (range, −3°-19°) in the lordotic and parallel graft patient groups, respectively. There were no statistically significant differences in clinical outcome scores between the lordotic and parallel graft patient groups. However, patients who had maintained or improved segmental sagittal alignment, regardless of graft type, achieved a higher degree of improvement in Short Form-36 Physical Component Summary and Neck Disability Index scores. This was statistically significant (P < .038). CONCLUSION:The use of lordotically shaped allografts does not increase cervical/segmental sagittal alignment or improve clinical outcomes. Maintaining a consistent segmental sagittal alignment or increasing segmental lordosis was related to a higher degree of improvement in clinical outcomes.

Complications in patients undergoing combined transforaminal lumbar interbody fusion and posterior instrumentation with deformity correction for degenerative scoliosis and spinal stenosis.

Background: Utilization of the transforaminal lumbar interbody fusion (TLIF) approach for scoliosis offers the patients deformity correction and interbody fusion without the additional morbidity associated with more invasive reconstructive techniques. Published reports on complications associated with these surgical procedures are limited. The purpose of this study was to quantify the intra- and postoperative complications associated with the TLIF surgical approach in patients undergoing surgery for spinal stenosis and degenerative scoliosis correction. Methods: This study included patients undergoing TLIF for degenerative scoliosis with neurogenic claudication and painful lumbar degenerative disc disease. The TLIF technique was performed along with posterior pedicle screw instrumentation. The average follow-up time was 30 months (range, 15–47). Results: A total of 29 patients with an average age of 65.9 years (range, 49–83) were evaluated. TLIFs were performed at 2.2 levels on average (range, 1–4) in addition to 6.0 (range, 4–9) levels of posterolateral instrumented fusion. The preoperative mean lumbar lordosis was 37.6° (range, 16°–55°) compared to 40.5° (range, 26°–59.2°) postoperatively. The preoperative mean coronal Cobb angle was 32.3° (range, 15°–55°) compared to 15.4° (range, 1°–49°) postoperatively. The mean operative time was 528 min (range, 276–906), estimated blood loss was 1091.7 mL (range, 150–2500), and hospitalization time was 8.0 days (range, 3–28). A baseline mean Visual Analog Scale (VAS) score of 7.6 (range, 4–10) decreased to 3.6 (range, 0–8) postoperatively. There were a total of 14 (49%) hardware and/or surgical technique related complications, and 8 (28%) patients required additional surgeries. Five (17%) patients developed pseudoarthrosis. The systemic complications (31%) included death (1), cardiopulmonary arrest with resuscitation (1), myocardial infarction (1), pneumonia (5), and pulmonary embolism (1). Conclusion: This study suggests that although the TLIF approach is a feasible and effective method to treat degenerative adult scoliosis, it is associated with a high rate of intra- and postoperative complications and a long recovery process.

The duration of symptoms and clinical outcomes in patients undergoing anterior cervical discectomy and fusion for degenerative disc disease and radiculopathy

BACKGROUND CONTEXT There have been controversial reports published in the literature on the duration of symptoms (DOS) and clinical outcome correlation in patients undergoing anterior cervical discectomy and fusion (ACDF) for painful degenerative disc disease and radiculopathy. PURPOSE The primary purpose of this study was to analyze if the DOS has any effect on clinical outcomes. STUDY DESIGN/SETTING A post hoc analysis was performed on an original prospective clinical study analyzing clinical outcomes and cervical sagittal alignment correlations. PATIENTS SAMPLE Fifty-eight patients undergoing one- or two-level ACDF surgeries for cervical degenerative radiculopathy were analyzed. OUTCOME MEASURES Standardized questionnaires were used to evaluate clinical outcomes. Neck and arm pain was evaluated using (Visual Analog Scale [VAS]). Two scales of Health-Related Quality-of-Life Questionnaire (Short-Form 36 Health Survey [SF-36]) were used for this study: the physical component summary (PCS) and mental component summary (MCS). Neck disability index (NDI) was used to evaluate chronic disability in activities of daily living. The patients completed a self-reported Patient Satisfaction with Results Survey. METHODS Patients who had previous or redo surgeries, were diagnosed with myelopathy or had more than two-level ACDF surgeries were excluded, leaving a total of 58 patients. The mean follow-up was 37.2 months (range 12-54). Patients were divided into two groups for clinical outcome analyses according to the DOS: patients who had surgery within 6 months (n=29) or more than 6 months (n=29) after becoming symptomatic. RESULTS There were no statistically significant differences in any demographic or clinical parameters among the patient groups. Controlling for preoperative scores, the patients who had surgery within 6 months reported significantly higher reduction (p=.04) in arm pain scores compared with the patients who waited more than 6 months. No significant differences were detected in postoperative neck pain VAS (p=.3), NDI (p=.06), SF-36 PCS (p=.08), and MCS (p=.8) scores. CONCLUSIONS Neck and upper extremity pain can be successfully treated conservatively. In those cases, when surgical intervention is pursued, patients with shorter DOS have better improvement in radiculopathy symptoms that is statistically significant.

Prediction based on preoperative opioid use of clinical outcomes after transforaminal lumbar interbody fusions

OBJECTIVE Opioid analgesics have become some of the most prescribed drugs in the world, despite the lack of long-term studies evaluating the benefits of opioid medications versus their risks associated with chronic use. In addition, long-term opioid use may be associated with worse long-term clinical outcomes. The primary objective of this study was to evaluate whether preoperative opioid use predicted inferior clinical outcomes among patients undergoing transforaminal lumbar interbody fusion (TLIF) for symptomatic lumbar degenerative disc disease. METHODS The authors of this observational study prospectively enrolled 93 patients who underwent 1-level to 2-level TLIFs in 2011-2014; the patient cohort was divided into 2 groups according to preoperative opioid use or no such use. Visual analog scale (VAS) scores for low-back pain and leg pain, Oswestry Disability Index scores, and the scores of the mental component summary (MCS) and physical component summary (PCS) on the 36-Item Short Form Health Survey were used to assess pain, disability, and health-related quality of life outcomes, respectively. The clinical scores for the 2 groups were determined preoperatively and at a 12-month follow-up examination. RESULTS In total, 60 (64.5%) patients took prescribed opioid medications preoperatively. Compared with those not taking opioids preoperatively, these patients had significantly higher VAS scores for low-back pain (p = 0.016), greater disability (p = 0.013), and lower PCS scores (p = 0.03) at the 12-month follow-up. The postoperative MCS scores were also significantly lower (p = 0.035) in the opioid-use group, but these lower scores were due to significantly lower baseline MCS scores in this group. A linear regression analysis did not detect opioid dose-related effects on leg and back pain, disability, and MCS and PCS scores, suggesting that poorer outcomes are not significantly correlated with higher opioid doses taken by the patients. CONCLUSIONS The use of opioid medications to control pain before patients underwent lumbar fusion for degenerative lumbar conditions was associated with less favorable clinical outcomes postoperatively. This is the first study that has demonstrated this association in a homogeneous cohort of patients undergoing TLIF; this association should be studied further to evaluate the conclusions of the present study. Clinical trial registration no.: NCT01406405 ( clinicaltrials.gov ).

Unilateral and Bilateral Pedicle Screw Fixation in Transforaminal Lumbar Interbody Fusion: Radiographic and Clinical Analysis

BACKGROUND Transforaminal lumbar interbody fusion with bilateral segmental pedicle screw (PS) fixation is a widely used and well-recognized technique that provides fixation and load-bearing capacity, while restoring morphometric spine parameters and relieving symptoms in patients with degenerative disc disease. A supplemental interspinous process fixation plate (ISFP) as an adjunct to unilateral PS fixation allows for reduced invasiveness of this technique compared with bilateral PS placement. The biomechanical comparison results have been previously reported, but the significance of these findings has not been studied in clinical settings. METHODS A prospective cohort study with a supplemental retrospective chart review and radiographic analysis was performed. Patients were divided into 2 groups: bilateral PS fixation (n = 75) or unilateral PS fixation + ISFP (n = 96). Lateral lumbar standing radiographs were obtained for preoperative and postoperative foraminal height (FH), disc height, segmental sagittal alignment, and lumbar sagittal alignment measurements. Standardized questionnaires were used to compare postoperative clinical outcomes. RESULTS The estimated blood loss, duration of procedure, and length of hospital stay were significantly lower for 1-level and 2-level procedures in the unilateral PS + ISFP group. A statistically significant mean disc height increase was observed in both groups. Regardless of the disc height increase, a statistically significant FH loss was detected in the bilateral PS group (from 17.1 mm to 16.3 mm; 4.7% loss; P = 0.04) compared with FH height loss in the unilateral PS + ISFP group that was not statistically significant (from 19.0 mm to 18.4 mm; 3.2% loss; P = 0.1). The analysis of segmental sagittal alignment, lumbar sagittal alignment, clinical outcomes, and fusion rates did not demonstrate any statistically significant differences. CONCLUSIONS Significantly reduced surgical invasiveness was associated with unilateral PS + ISFP fixation, which represents the major advantage of this technique. Unilateral fixation was also associated with a slightly lower reduction in FH and was equally effective as bilateral PS fixation in regard to fusion rates, clinical outcomes, and other radiographic outcomes studied.

A Novel Case of Resolved Postherpetic Neuralgia with Subsequent Development of Trigeminal Neuralgia: A Case Report and Review of the Literature

A 72-year-old female patient is presented, who was diagnosed with herpes zoster along the left ophthalmic branch of the trigeminal nerve with associated cutaneous vesicles. The patient subsequently developed postherpetic neuralgia in the same dermatome, which, after remission, transformed into paroxysmal trigeminal pain. The two different symptom sets, with the former consistent with PHN and the later consistent with trigeminal neuralgia, were unique to our practice and the literature.

Case Series of Anterior Intervertebral Graft Extrusions in Transforaminal Lumbar Interbody Fusion Surgeries.

BACKGROUND According to the published reports, revision surgery is sometimes recommended even in patients with asymptomatic anterior lumbar intervertebral graft migrations. The main purpose of this chart review study was to report on the clinical course and outcomes of patients who had anterior intervertebral graft extrusions after transforaminal lumbar interbody fusion (TLIF). METHODS From July 2002 to July 2014, 1259 consecutive TLIF surgeries were performed. These were reviewed, and patients who had anterior intervertebral graft extrusions were identified. RESULTS The incidence of graft extrusion was 0.6% (7 of 1259 patients). There were 6 female patients and 1 male patient with an average age of 65.7 years (range, 44-80 years). All patients underwent TLIF with bilateral pedicle screw fixation, and 6 received recombinant human bone morphogenetic protein-2. Graft migrations were diagnosed between 5 days and 8 months postoperatively except for 2 cases in which migration occurred intraoperatively. The patients were closely followed for an average of 27.4 months (range, 12-43 months). All patients remained asymptomatic during the follow-up period and had solid fusion despite extrusions with an average time to fusion of 13 months (range, 10-18 months). No other adverse events occurred during the follow-up period. CONCLUSIONS The risks of additional and highly invasive revision surgery should be weighed against the potential short-term and long-term complications associated with graft extrusions or migrations. It was demonstrated that fusion may take longer but can be achieved, and close observation may be adequate for asymptomatic patients.