Mohamed Macki, Rafael De la Garza-Ramos, Ashley A. Murgatroyd, Kenneth P. Mullinix, Xiaolei Sun, Bryan W. Cunningham, Brandon A. McCutcheon, Mohamad Bydon and Ziya L. Gokaslan
Aggressive sacral tumors often require en bloc resection and lumbopelvic reconstruction. Instrumentation failure and pseudarthrosis remain a clinical concern to be addressed. The objective in this study was to compare the biomechanical stability of 3 distinct techniques for sacral reconstruction in vitro.
In a human cadaveric model study, 8 intact human lumbopelvic specimens (L2–pelvis) were tested for flexion-extension range of motion (ROM), lateral bending, and axial rotation with a custom-designed 6-df spine simulator as well as axial compression stiffness with the MTS 858 Bionix Test System. Biomechanical testing followed this sequence: 1) intact spine; 2) sacrectomy (no testing); 3) Model 1 (L3–5 transpedicular instrumentation plus spinal rods anchored to iliac screws); 4) Model 2 (addition of transiliac rod); and 5) Model 3 (removal of transiliac rod; addition of 2 spinal rods and 2 S-2 screws). Range of motion was measured at L4–5, L5–S1/cross-link, L5–right ilium, and L5–left ilium.
Flexion-extension ROM of the intact specimen at L4–5 (6.34° ± 2.57°) was significantly greater than in Model 1 (1.54° ± 0.94°), Model 2 (1.51° ± 1.01°), and Model 3 (0.72° ± 0.62°) (p < 0.001). Flexion-extension at both the L5–right ilium (2.95° ± 1.27°) and the L5–left ilium (2.87° ± 1.40°) for Model 3 was significantly less than the other 3 cohorts at the same level (p = 0.005 and p = 0.012, respectively). Compared with the intact condition, all 3 reconstruction groups statistically significantly decreased lateral bending ROM at all measured points. Axial rotation ROM at L4–5 for Model 1 (2.01° ± 1.39°), Model 2 (2.00° ± 1.52°), and Model 3 (1.15° ± 0.80°) was significantly lower than the intact condition (5.02° ± 2.90°) (p < 0.001). Moreover, axial rotation for the intact condition and Model 3 at L5–right ilium (2.64° ± 1.36° and 2.93° ± 1.68°, respectively) and L5–left ilium (2.58° ± 1.43° and 2.93° ± 1.71°, respectively) was significantly lower than for Model 1 and Model 2 at L5–right ilium (5.14° ± 2.48° and 4.95° ± 2.45°, respectively) (p = 0.036) and L5–left ilium (5.19° ± 2.34° and 4.99° ± 2.31°) (p = 0.022). Last, results of the axial compression testing at all measured points were not statistically different among reconstructions.
The addition of a transverse bar in Model 2 offered no biomechanical advantage. Although the implementation of 4 iliac screws and 4 rods conferred a definitive kinematic advantage in Model 3, that model was associated with significantly restricted lumbopelvic ROM.
Rafael De la Garza-Ramos, Risheng Xu, Seba Ramhmdani, Thomas Kosztowski, Mohamad Bydon, Daniel M. Sciubba, Jean-Paul Wolinsky, Timothy F. Witham, Ziya L. Gokaslan and Ali Bydon
The purpose of this study was to report the long-term clinical outcomes following 3- and 4-level anterior cervical discectomy and fusion (ACDF).
A retrospective review of all adult neurosurgical patients undergoing elective ACDF for degenerative disease at a single institution between 1996 and 2013 was performed. Patients who underwent first-time 3- or 4-level ACDF were included; patients with previous cervical spine surgery, those undergoing anterior/posterior approaches, and those with corpectomy were excluded. Outcome measures included perioperative complication rates, fusion rates, need for revision surgery, Nurick Scores, Odom's criteria, symptom resolution, neck visual analog scale (VAS) pain score, and persistent narcotics usage.
Seventy-one patients who underwent 3-level ACDF and 26 patients who underwent 4-level ACDF were identified and followed for an average of 7.6 ± 4.2 years. There was 1 case (3.9%) of deep wound infection in the 4-level group and 1 case in the 3-level group (1.4%; p = 0.454). Postoperatively, 31% of patients in the 4-level group complained of dysphagia, compared with 12.7% in the 3-level group (p = 0.038). The fusion rate was 84.6% after 4-level ACDF and 94.4% after 3-level ACDF (p = 0.122). At last follow-up, a significantly higher proportion of patients in the 4-level group continued to have axial neck pain (53.8%) than in the 3-level group (31%; p = 0.039); the daily oral morphine equivalent dose was significantly higher in the 4-level group (143 ± 97 mg/day) than in the 3-level group (25 ± 10 mg/day; p = 0.030). Outcomes based on Odom's criteria were also different between cohorts (p = 0.044), with a significantly lower proportion of patients in the 4-level ACDF group experiencing an excellent/good outcome.
In this study, patients who underwent 4-level ACDF had significantly higher rates of dysphagia, postoperative neck pain, and postoperative narcotic usage when compared with patients who underwent 3-level ACDF. Pseudarthrosis and deep wound infection rates were also higher in the 4-level group, although this did not reach statistical significance. Additionally, a smaller proportion of patients achieved a good/excellent outcome in the 4-level group than in the 3-level group. These findings suggest a significant increase of perioperative morbidity and worsened outcomes for patients who undergo 4- versus 3-level ACDF.
Mohamad Bydon, Rafael De la Garza-Ramos and Ziya L. Gokaslan
Mohamad Bydon, Nicholas B. Abt, Rafael De la Garza-Ramos, Mohamed Macki, Timothy F. Witham, Ziya L. Gokaslan, Ali Bydon and Judy Huang
The authors sought to determine the impact of resident participation on overall 30-day morbidity and mortality following neurosurgical procedures.
The American College of Surgeons National Surgical Quality Improvement Program database was queried for all patients who had undergone neurosurgical procedures between 2006 and 2012. The operating surgeon(s), whether an attending only or attending plus resident, was assessed for his or her influence on morbidity and mortality. Multivariate logistic regression, was used to estimate odds ratios for 30-day postoperative morbidity and mortality outcomes for the attending-only compared with the attending plus resident cohorts (attending group and attending+resident group, respectively).
The study population consisted of 16,098 patients who had undergone elective or emergent neurosurgical procedures. The mean patient age was 56.8 ± 15.0 years, and 49.8% of patients were women. Overall, 15.8% of all patients had at least one postoperative complication. The attending+resident group demonstrated a complication rate of 20.12%, while patients with an attending-only surgeon had a statistically significantly lower complication rate at 11.70% (p < 0.001). In the total population, 263 patients (1.63%) died within 30 days of surgery. Stratified by operating surgeon status, 162 patients (2.07%) in the attending+resident group died versus 101 (1.22%) in the attending group, which was statistically significant (p < 0.001). Regression analyses compared patients who had resident participation to those with only attending surgeons, the referent group. Following adjustment for preoperative patient characteristics and comorbidities, multivariate regression analysis demonstrated that patients with resident participation in their surgery had the same odds of 30-day morbidity (OR = 1.05, 95% CI 0.94–1.17) and mortality (OR = 0.92, 95% CI 0.66–1.28) as their attendingonly counterparts.
Cases with resident participation had higher rates of mortality and morbidity; however, these cases also involved patients with more comorbidities initially. On multivariate analysis, resident participation was not an independent risk factor for postoperative 30-day morbidity or mortality following elective or emergent neurosurgical procedures.
Mohamad Bydon, Mohamed Macki, Rafael De la Garza-Ramos, Daniel M. Sciubba, Jean-Paul Wolinsky, Ziya L. Gokaslan, Timothy F. Witham and Ali Bydon
This study aimed to identify the factors predicting an increased risk for reoperation in patients who had undergone a lumbar laminectomy.
The authors retrospectively reviewed the electronic medical records of all patients who had undergone firsttime, bilateral laminectomy at 1, 2, or 3 levels for lumbar spondylosis at the authors' institution. Patients who underwent fusion, laminotomy, discectomy, or complete facetectomy were excluded. The patients' preoperative symptoms and comorbidities were also obtained from their medical records.
Over an average follow-up period of 46.8 months, of 500 patients who had undergone laminectomy at 1, 2, or 3 levels, 81 patients (16.2%) developed subsequent spinal disorders that required a reoperation. A multiple logistic regression analysis identified smoking as an independent predictor of reoperation (OR 2.15, p = 0.01). Smoking was also an independent predictor of reoperation after a single-level laminectomy (OR 11.3, p = 0.02) and after a multilevel (that is, involving 2 or 3 levels) laminectomy (OR 1.98, p = 0.05). For 72 patients undergoing reoperation only for spinal degeneration, smoking remained an independent, statistically significant predictor of reoperation (OR 2.06, p = 0.04). Nine patients underwent reoperation for nondegenerative conditions (hematoma, wound infection, or wound dehiscence), and in these patients, chronic obstructive pulmonary disease was the only statistically significant predictor of reoperation (OR 8.92, p = 0.03).
Smoking was the strongest predictor of reoperation in patients who had undergone single-level laminectomy, multilevel laminectomy, or reoperation for progression of spinal degeneration. These findings suggest that smokers have worse outcomes of lumbar decompression than nonsmokers.