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Interspinous devices have been introduced to provide a minimally invasive surgical alternative for patients with lumbar spinal stenosis or foraminal stenosis. Little is known however, of the effect of interspinous devices on intersegmental range of motion (ROM). The aim of this in vivo study was to investigate the effect of a novel minimally invasive interspinous implant, InSwing, on sagittal plane ROM of the lumbar spine using an ovine model. Ten adolescent Merino lambs underwent a destabilization procedure at the L1-L2 level simulating a stenotic degenerative spondylolisthesis (as described in our earlier work; Spine 15:571-576, 1990). All animals were placed in a side-lying posture and lateral radiographs were taken in full flexion and extension of the trunk in a standardized manner. Radiographs were repeated following the insertion of an 8-mm InSwing interspinous device at L1-L2, and again with the implant secured by means of a tension band tightened to 1 N/m around the L1 and L2 spinous processes. ROM was assessed in each of the three conditions and compared using Cobb's method. A paired t-test compared ROM for each of the experimental conditions (P < 0.05). After instrumentation with the InSwing interspinous implant, the mean total sagittal ROM (from full extension to full flexion) was reduced by 16% from 6.3 degrees to 5.3 +/- 2.7 degrees. The addition of the tension band resulted in a 43% reduction in total sagittal ROM to 3.6 +/- 1.9 degrees which approached significance. When looking at flexion only, the addition of the interspinous implant without the tension band did not significantly reduce lumbar flexion, however, a statistically significant 15% reduction in lumbar flexion was observed with the addition of the tension band (P = 0.01). To our knowledge, this is the first in vivo study radiographically showing the advantage of using an interspinous device to stabilize the spine in flexion. These results are important findings particularly for patients with clinical symptoms related to instable degenerative spondylolisthesis. [ABSTRACT FROM AUTHOR]

Objective: This study assessed utilization and cost of allogeneic blood transfusion (ABT) associated with spinal surgery in the United States (US) and Belgium.Methods: A retrospective cohort of 292,864 spinal surgery inpatients in US hospitals was pooled with a cohort of 27,952 inpatients who had similar procedures in Belgian hospitals. Utilization and cost data were derived from hospital accounting systems. Costs were converted to US dollars. Descriptive and multivariate statistics were used to describe the factors associated with the use and cost of ABT. Missing data, confounding, and variable measurement error were addressed using standard approaches for observational studies.Results: US hospitalizations cost $12,044 (SD = 15,920) over 3.6 days compared to $4010 (SD = 3586) over 10.3 days in Belgium. Low molecular weight heparin was used by 78% of Belgian patients and 4% of US patients. Red blood cell utilization occurred in approximately 7% of patients from both countries; however US patients received 6 units compared to 3 units by Belgian patients. US patients spent 3.5 (p < 0.0001) less days in hospital, 1.0 (p < 0.0001) more days in an intensive care unit, used 64% more allogeneic blood (OR = 1.64, 95% CI 1.53-1.75), and incurred $13,647 (p < 0.0001) more per hospitalization than Belgian patients.Conclusions: US patients used more blood products, had shorter hospital stays, and incurred greater costs than Belgian patients. Specialists as attending physicians were associated with lower utilization of ABT; this may be an administrative change that hospitals can implement to reduce utilization and costs. [ABSTRACT FROM AUTHOR]

Lifting restrictions postoperatively are quite common, but there appears to be little scientific basis for them. Lifting restrictions are inhibitory in terms of return to work and may be a factor in chronicity. The mean functional spinal motion unit stiffness changes with in vitro or computer-simulated discectomies, facetectomies and laminectomies were reviewed from the literature. We modified the NIOSH lifting equation to include another multiplier related to stiffness change post surgery. The new recommended lifts were computed for different lifting conditions seen in industry. The reduction of rotational stiffness ranged from 21% to 41% for a discectomy, 1% to 59% for a facetectomy and 4% to 16% for a partial laminectomy. The recommended lifts based on our modified equation were adjusted accordingly. There is no rational basis for current lifting restrictions. The risk to the spine is a function of many other variables as well as weight (i.e., distance of weight from body). The adjusted NIOSH guidelines provide a reasonable way to estimate weight restrictions and accommodations such as lifting aids. Such restrictions should be as liberal as possible so as to facilitate, not prevent, return to work. Patients need more advice regarding lifting activities and clinicians should be more knowledgeable about the working conditions and constraints of a given workplace to effectively match the solution to the patient's condition. [ABSTRACT FROM AUTHOR]

The efficacy of an NSAID (tenoxicam) in the treatment of acute low back pain (LBP) was assessed in a double blind controlled study by using an objective functional evaluation. Seventy-three patients consulting for acute LBP were randomized into two groups: Group I was treated with tenoxicam for 14 days and Group II was given a placebo. Trunk function was measured with a computerized isoinertial dynamometric trunk testing device (Isostation B200). Isometric and dynamic torques, range of motion and movement velocities were measured before treatment and after 14 days. Clinical evaluation was realized by the patient on a pain visual analogue scale (VAS) on days 1,8 and 15 and by the investigator on a five-point scale on days 8 and 15. The functional evaluation showed significant differences in favour of the tenoxicam treatment for velocity and extension isometric torque. VAS and investigator evaluations showed a significant difference in favour of tenoxicam on day 8 but no difference on day 15. This study shows that the use of tenoxicam in acute LBP is of interest. Tenoxicam has an effect on pain during the first part of the treatment and may help to restore full function even if the symptoms have disappeared. [ABSTRACT FROM PUBLISHER]

The author reflects on the several techniques which are use in pediatric spinal surgery. Topics discussed include the origination of medical term pediatric orthopedics, the vertebral surgery for spine deformities as major branch of pediatric surgery, and the three-dimensional analysis which uses low-dose imaging system including EOS imaging which ca provide accurate analysis of scoliosis deformities.

Background: Quantitative objective measures to determine fusion achievement further enable the comparison of new technologies, such as interbody cage surface enhancement. Our aims were to compare in vivo biomechanical responses of ovine L4/5 lumbar motion segments with two cages: 1) Polyetheretherketone or 2) Polyetheretherketone with a nanosurfaced titanium porous scaffold from Nanovis, Inc., Methods: Fourteen Merino sheep randomly received either 1) standard Polyetheretherketone cage or 2) Nanocoated Polyetheretherketone cage at L4/L5 with autologous bone graft. At baseline and one-year follow-up, dynamic spinal stiffness was quantified in vivo using a validated mechanical assessment at 2 Hz, 6 Hz, and 12 Hz. The dorsoventral secant stiffness (k y  = force/displacement, N/mm) and L4-L5 accelerations were determined at each frequency. A repeated measures analysis of variance with Bonferonni correction was used to evaluate within and between group differences among the biomechanical variables., Findings: Both implants increased spinal stiffness at 2 Hz (21 and 39%, respectively, p < .005), and at 6 Hz (12 and 27%, p < .0001). Significantly greater spinal stiffness was observed with Nanocoated Polyetheretherketone at one-year for both frequencies (p < .05). No significant differences were observed at 12 Hz within or between groups. L4-L5 dorsoventral accelerations were significantly decreased one year following cage placement only with Nanocoated Polyetheretherketone (p < .05) and greater reductions in acceleration were observed with Nanocoated Polyetheretherketone compared to standard Polyetheretherketone (p < .05)., Interpretation: Both cages increased spinal stiffness, yet, nanosurfaced cages resulted in greater spinal stiffness changes and decreases in L4-L5 accelerations. These findings may assist in clinical decision making and post-operative recovery strategies., (Copyright © 2019 Elsevier Ltd. All rights reserved.)