Resting Pain Level as a Preoperative Predictor of Success With Indirect Decompression for Lumbar Spinal Stenosis: A Pilot Study.

STUDY DESIGN: Retrospective review of a single institution. OBJECTIVE: To determine if resting leg pain level is a predictor of success for indirect decompression in the setting of lumbar spinal stenosis, with lower levels of rest pain correlating with greater likelihood of successful indirect decompression. METHODS: Reviewed anterior or lateral lumbar interbody fusions from T12 to L5-S1 patients with a posterior-based pedicle screw-rod construct. Patients were separated into 2 groups based on a preoperative response to Oswestry Disability Index (ODI) Question 7 regarding level of pain at rest in the supine position. Responses of 0 to 2 (minimal rest pain) were group 1 (n = 54) and responses of 3 to 5 (significant rest pain) were group 2 (n = 16). RESULTS: Preoperative difference was detected between groups 1 and 2, in ODI (38 vs 63, P < .001) and Numeric Rating Scale (NRS) back (6.8 vs 7.9, P = .023). Three-month NRS leg and back scores were significantly lower in group 1 (leg, 1.9 vs 4.8, P < .001; back, 3.5 vs 6.4, P = .001). A significant difference was further noted in the percentage decrease in NRS leg and back scores from pre- to 3 months postoperatively between groups 1 and 2 (leg, 68.4% vs 22.7%, P < .001; back, 40.0% vs 7.4%, P = .012). Group 1 reached minimal clinically important difference for leg pain more often than group 2 (83.3% vs 43.8%, P = .001). CONCLUSION: Preoperative assessment of rest pain level in the supine position has a significant association with reduction in NRS leg and back scores in patients undergoing indirect decompression for lumbar spinal stenosis. This tool may successfully indicate which patients will be candidates for indirect decompression with interbody fusion from an anterior or lateral approach.

Home Versus Rehabilitation: Factors that Influence Disposition After Minimally Invasive Surgery in Adult Spinal Deformity Surgery.

BACKGROUND: Minimally invasive surgery (MIS) correction for adult spinal deformity (ASD) may reduce the need the need for postoperative skilled nursing facility (SNF) or inpatient rehabilitation (IR) placement following surgery. The likelihood of requiring placement in a facility rather than home disposition may be influenced by various factors. In addition, the associations between discharge location and outcomes and complication rates have not been elucidated in these patients. In this study, we aimed to define factors predicting disposition to an SNF/IR and to elucidate the rates of complications occurring in patients sent to home versus to a facility. METHODS: A retrospective review of a multicenter ASD database, which included patients who underwent surgery between 2009 and 2014. Inclusion criteria were age >18 years, MIS as part of index surgery, location of discharge, and at least 1 of the following: pelvic tilt >20°, sagittal vertical axis >5 cm, pelvic incidence-lumbar lordosis mismatch >10, or lumbar scoliosis >20°. Patients with a 2-year follow-up were included. Preoperative demographic and radiographic data, postoperative (<30 day) complications, and health-related quality of life were analyzed. RESULTS: A total of 182 patients met our inclusion criteria, including 113 who were discharged to home and 69 who were discharged to an SNF/IR. Older patients (>50 years) were more likely to be discharged to an SNF/IR (P = 0.043). Those aged >70 years were 6-fold more likely to go to an SNF/IR. No association was identified between discharge to an SNF/IR and any radiographic parameters except preoperative pelvic tilt (odds ratio [OR], 1.11; P = 0.009). Staged cases were more likely to be discharged to an SNF/IR (OR, 3.24; 95% confidence interval, 1.11-9.46; P = 0.032); otherwise, there was no difference in levels treated, operating time, estimated blood loss, osteotomy, or length of hospital stay. Patients requiring discharge to an SNF/IR had a higher rate of complications (58% vs. 39.8%; P = 0.017), including major complications (19.5% vs. 42%; P = 0.001), perioperative complications (14.2% vs. 31.9%; P = 0.004) and infections (3.5% vs. 13%; P = 0.016). Patients discharged to an SNF/IR had a higher rate of revision (19.5% vs. 33%; P = 0.035). Health-related quality of life measures were similar regardless of disposition. CONCLUSIONS: Older patients and those undergoing staged MIS deformity correction have a higher likelihood of postoperative disposition to an SNF/IR. Complications occurred more commonly in those patients requiring transfer to an SNF/IR after hospitalization.

Variability in Assessing Spinopelvic Parameters With Lumbosacral Transitional Vertebrae: Inter- and Intraobserver Reliability Among Spine Surgeons.

STUDY DESIGN: Prospectively collected survey study OBJECTIVE.: The aim of this study was to determine the consistency with which spinopelvic parameters (SPP) are determined in patients with lumbosacral transitional vertebrae (LSTV). SUMMARY OF BACKGROUND DATA: The incidence of LSTV in the general population is as high as 35.6%. The often fixed nature of LSTV relative to the pelvis, but lumbar-type appearance, may lead to differential use of the S1 endplate when performing SPP assessment. This could have significant impact on SPP derived from these landmarks, resulting in considerable variation in surgical planning and decision-making. METHODS: Twenty patients demonstrating LSTV on standing lateral 36-inch spinal radiographs were randomly arranged and independently analyzed by 16 experienced spine surgeons using the same computer software. Pelvic incidence (PI), pelvic tilt (PT), lumbar lordosis (LL), and T1 pelvic angle (TPA) were captured. Two weeks after the first assessment, surgeons repeated the measurements after image sequence re-randomization. Intraclass correlation coefficient (ICC) was calculated to evaluate interobserver reliability (IOR) for each SPP. Intraobserver reliability (IAOR) was assessed through an average Pearson correlation coefficient for each parameter for each surgeon. RESULTS: Sixteen surgeons completed initial measurements. IOR was poor for TPA (0.35, 95% confidence interval [CI] 0.20, 0.58) and PI (0.42, 95% CI 0.26, 0.65) and fair for LL (0.67, 95% CI 0.51, 0.82), and PT (0.63, 95% CI 0.47, 0.81). Fourteen surgeons completed phase-2 measurements to assess IAOR. Average parameter PPC showed excellent IAOR (LL 0.86, TPA 0.77, PI 0.78, PT 0.86). Kappa coefficient showed fair agreement for raters choosing the same endplate for measurement (Phase 1: 0.38, Phase 2: 0.32). By patient, the percentage of raters that chose the S1 endplate for measurement varied from 6.3% to 85.7%. CONCLUSION: Significant variability exists when surgeons measure SPP in patients with LSTV. These parameters are critical in determining the goals of surgical reconstruction and such variability may have considerable implications for radiographic goals and outcomes of surgical reconstruction. LEVEL OF EVIDENCE: 4.

Single position versus lateral-then-prone positioning for lateral interbody fusion and pedicle screw fixation.

BACKGROUND: To compare perioperative and radiographic outcomes following lateral lumbar interbody fusions in two cohorts of patients who either underwent single position or dual position surgery. METHODS: Patients over the age of 18 with degenerative lumbar pathology who underwent a lumbar interbody fusion via lateral access from 2012-2015 from a single surgeon met inclusion criteria. Patients who underwent combined procedures, had a history of retroperitoneal surgery, or had inadequate preoperative imaging were excluded. Patients who remained in the lateral decubitus position for pedicle screw fixation [single-position (SP)] were compared to those turned prone [dual-position (DP)]. Demographics, surgical details, and perioperative outcomes were compared between groups. RESULTS: A total of 42 SP and 24 DP patients were analyzed. The DP group had a 44.4-minute longer operating room time compared to the SP group (P<0.001) after adjusting for the number of levels operated (P<0.001) and unilateral versus bilateral screw placement (P=0.048). Otherwise, no differences were observed in peri-operative outcomes. Lordosis was not different between groups pre-operatively (P>0.999) or post-operatively (P=0.479), and neither was the pre- to post-operative change (P=0.283). CONCLUSIONS: Lateral pedicle screw fixation following lateral interbody fusion decreases operating room time without compromising post-operative lordosis, complication rates, or perioperative outcomes.

Cancellous Screws Are Biomechanically Superior to Cortical Screws in Metaphyseal Bone.

Cancellous screws are designed to optimize fixation in metaphyseal bone environments; however, certain clinical situations may require the substitution of cortical screws for use in cancellous bone, such as anatomic constraints, fragment size, or available instrumentation. This study compares the biomechanical properties of commercially available cortical and cancellous screw designs in a synthetic model representing various bone densities. Commercially available, fully threaded, 4.0-mm outer-diameter cortical and cancellous screws were tested in terms of pullout strength and maximum insertion torque in standard-density and osteoporotic cancellous bone models. Pullout strength and maximum insertion torque were both found to be greater for cancellous screws than cortical screws in all synthetic densities tested. The magnitude of difference in pullout strength between cortical and cancellous screws increased with decreasing synthetic bone density. Screw displacement prior to failure and total energy absorbed during pullout strength testing were also significantly greater for cancellous screws in osteoporotic models. Stiffness was greater for cancellous screws in standard and osteoporotic models. Cancellous screws have biomechanical advantages over cortical screws when used in metaphyseal bone, implying the ability to both achieve greater compression and resist displacement at the screw-plate interface. Surgeons should preferentially use cancellous over cortical screws in metaphyseal environments where cortical bone is insufficient for fixation. [Orthopedics.2016; 39(5):e828-e832.].

Endoscopic-assisted epiphysiodesis: technique and 20-year experience.

The aim of the study was to describe the endoscopic-assisted epiphysiodesis technique and review our 20-year experience with it. A retrospective review of 44 patients who underwent proximal tibia and/or distal femur endoscopic-assisted epiphysiodesis was carried out. Only patients who had preoperative and postoperative scanograms with clinical follow-up of at least 6 months were included. The mean length of follow-up was 36.8 months. All patients had radiographic evidence of physeal fusion within 6-12 months from the index procedure. No patient required revision surgery. Endoscopic-assisted epiphysiodesis is safe, effective, and achieves predictable physeal fusion. Advantages over current techniques include reduced radiation exposure and lack of requirement for hardware placement.