Real time interrater reliability of a novel musculoskeletal readiness screening tool.

Military service members receive regular screenings for a variety of health conditions, but a field-expedient and military-specific screening tool that identifies an individual's risk for injury has not yet been identified. The purpose of this study is to describe the conduct of a novel musculoskeletal readiness screening tool (MRST) and evaluate the real-time interrater reliability of the MRST when scored by raters with differing levels of medical experience. MATERIALS/METHODS: This study included a convenience sample of 40 active duty military participants (30 male, 10 female, mean age 29.3±6.9 years) without any current musculoskeletal injury or pain at the time of enrollment. The MRST consisted of 5 physical performance tests and one self-report question as follows: (1) weight-bearing lunge (WBL), (2) overhead squat, (3) closed kinetic chain upper extremity stability test (CKCUEST), (4) eyes closed forward step down, (5) repeated tuck jump, and (6) individual perceived level of risk for MSK injury. Three raters (a board certified physical therapist with 15 years of experience, a physical therapy student with less than one year didactic training, and a physical therapy technician with approximately 10 years of experience) independently scored each event as 0, 1, or 2 based on the quality of the participant's performance. This scoring system allows for a cumulative score ranging from 0 to 12, with lower scores thought to indicate higher risk for future injury. Descriptive, reliability, and chance-corrected agreement statistics were calculated using IBM SPSS. This study was approved by the Brooke Army Medical Center Institutional Review Board at Fort Sam Houston, Texas. RESULTS: The mean composite MRST score for all graders was 7.79±1.41. Among all 3 raters the overall reliability was moderate (ICC (2,1)=0.75 (0.62, 0.85)). Chance-corrected agreement values for the individual events ranged from slight to almost perfect as follows: WBL (κ=0.33-0.44), overhead squat (κ=0.57-0.65), CKCUEST (κ=0.89-1.0), eyes-closed forward step down (κ=0.10-0.42), repeated tuck jump (κ=0.39-0.61), individual perceived level of risk for MSK injury (κ=1.0). CONCLUSIONS: The MRST showed moderate interrater reliability for the overall composite score with varied levels of agreement for individual events scores. Future research should investigate test-retest reliability and interrater reliability among medical personnel from different disciplines.

Nucleus implantation: the biomechanics of augmentation versus replacement with varying degrees of nucleotomy.

Nucleus pulposus replacement and augmentation has been proposed to restore disk mechanics in early stages of degeneration with the option of providing a minimally invasive procedure for pain relief to patients with an earlier stage of degeneration. The goal of this paper is to examine compressive stability of the intervertebral disk after either partial nucleus replacement or nuclear augmentation in the absence of denucleation. Thirteen human cadaver lumbar anterior column units were used to study the effects of denucleation and augmentation on the compressive mechanical behavior of the human intervertebral disk. Testing was performed in axial compression after incremental steps of partial denucleation and subsequent implantation of a synthetic hydrogel nucleus replacement. In a separate set of experiments, the disks were not denucleated but augmented with the same synthetic hydrogel nucleus replacement. Neutral zone, range of motion, and stiffness were measured. The results showed that compressive stabilization of the disk can be re-established with nucleus replacement even for partial denucleation. Augmentation of the disk resulted in an increase in disk height and intradiskal pressure that were linearly related to the volume of polymer implanted. Intervertebral disk instability, evidenced by increased neutral zone and ranges of motion, associated with degeneration can be restored by volume filling of the nucleus pulposus using the hydrogel device presented here.

The role of the nucleus pulposus in neutral zone human lumbar intervertebral disc mechanics.

To study the effect of denucleation on the mechanical behavior of the human lumbar intervertebral disc through a 2mm incision, two groups of six human cadaver lumbar spinal units were tested in axial compression, axial rotation, lateral bending and flexion/extension after incremental steps of "partial" denucleation. Neutral zone, range of motion, stiffness, intradiscal pressure and energy dissipation were measured; the results showed that the contribution of the nucleus pulposus to the mechanical behavior of the intervertebral disc was more dominant through the neutral zone than at the farther limits of applied loads and moments.