Browsing by Subject "Range of Motion, Articular"

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    ItemOpen Access
    Comparative effects of multilevel muscle tendon surgery, osteotomies, and dorsal rhizotomy on functional and gait outcome measures for children with cerebral palsy.
    (PM & R : the journal of injury, function, and rehabilitation, 2015-05) Feger, Mark A; Lunsford, Christopher D; Sauer, Lindsay D; Novicoff, Wendy; Abel, Mark F

    Objective

    To compare the impact of common surgical interventions (selective dorsal rhizotomy, muscle-tendon surgery, and osteotomies) for patients with cerebral palsy (CP) on Gross Motor Function Measure and temporal, kinematic, and kinetic gait variables as assessed via 3-dimensional motion analysis.

    Design

    Retrospective cohort study.

    Setting

    Motion analyses laboratory.

    Participants

    Ninety-four patients with CP, 56 of whom underwent surgery (37, muscle-tendon surgery; 11, osteotomy; and 8, selective dorsal rhizotomy) and 38 of whom did not have surgery; the patients were ages 4-18 years, with a Gross Motor Function Classification System classification of I, II, or III.

    Interventions

    Single-event, multilevel muscle tendon surgery, selective dorsal rhizotomy, and osteotomy.

    Main outcome measures

    Change scores (postintervention - preintervention) in Gross Motor Function Measure and temporal, kinematic, and kinetic gait variables.

    Results

    No statistically significant differences in change scores were found between groups in the Gross Motor Function Measure, velocity, or stride length measures after the observation period. The selective dorsal rhizotomy group had greater improvements in knee extension when compared with the nonsurgical group and greater hip and knee total range of motion during the gait cycle when compared with nonsurgical group and the muscle-tendon surgery and osteotomy cohorts. Lastly, the muscle-tendon surgery group had greater improvements in total knee range of motion compared with the nonsurgical group.

    Conclusions

    Patients who undergo selective dorsal rhizotomy and, to a lesser extent, muscle tendon procedures demonstrate greater improvements in kinematic gait variables compared with nonsurgical interventions in patients with spasticity resulting from CP.
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    ItemOpen Access
    Faced joint locking.
    (Journal of neurosurgery. Spine, 2011-01) Shaffrey, Christopher I
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    ItemOpen Access
    Hip extensor mechanics and the evolution of walking and climbing capabilities in humans, apes, and fossil hominins.
    (Proceedings of the National Academy of Sciences of the United States of America, 2018-04-02) Kozma, Elaine E; Webb, Nicole M; Harcourt-Smith, William EH; Raichlen, David A; D'Août, Kristiaan; Brown, Mary H; Finestone, Emma M; Ross, Stephen R; Aerts, Peter; Pontzer, Herman
    The evolutionary emergence of humans' remarkably economical walking gait remains a focus of research and debate, but experimentally validated approaches linking locomotor capability to postcranial anatomy are limited. In this study, we integrated 3D morphometrics of hominoid pelvic shape with experimental measurements of hip kinematics and kinetics during walking and climbing, hamstring activity, and passive range of hip extension in humans, apes, and other primates to assess arboreal-terrestrial trade-offs in ischium morphology among living taxa. We show that hamstring-powered hip extension during habitual walking and climbing in living apes and humans is strongly predicted, and likely constrained, by the relative length and orientation of the ischium. Ape pelves permit greater extensor moments at the hip, enhancing climbing capability, but limit their range of hip extension, resulting in a crouched gait. Human pelves reduce hip extensor moments but permit a greater degree of hip extension, which greatly improves walking economy (i.e., distance traveled/energy consumed). Applying these results to fossil pelves suggests that early hominins differed from both humans and extant apes in having an economical walking gait without sacrificing climbing capability. Ardipithecus was capable of nearly human-like hip extension during bipedal walking, but retained the capacity for powerful, ape-like hip extension during vertical climbing. Hip extension capability was essentially human-like in Australopithecus afarensis and Australopithecus africanus, suggesting an economical walking gait but reduced mechanical advantage for powered hip extension during climbing.
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    ItemOpen Access
    Impact of dynamic alignment, motion, and center of rotation on myelopathy grade and regional disability in cervical spondylotic myelopathy.
    (Journal of neurosurgery. Spine, 2015-12) Liu, Shian; Lafage, Renaud; Smith, Justin S; Protopsaltis, Themistocles S; Lafage, Virginie C; Challier, Vincent; Shaffrey, Christopher I; Radcliff, Kris; Arnold, Paul M; Chapman, Jens R; Schwab, Frank J; Massicotte, Eric M; Yoon, S Tim; Fehlings, Michael G; Ames, Christopher P

    Object

    Cervical stenosis is a defining feature of cervical spondylotic myelopathy (CSM). Matsunaga et al. proposed that elements of stenosis are both static and dynamic, where the dynamic elements magnify the canal deformation of the static state. For the current study, the authors hypothesized that dynamic changes may be associated with myelopathy severity and neck disability. This goal of this study was to present novel methods of dynamic motion analysis in CSM.

    Methods

    A post hoc analysis was performed of a prospective, multicenter database of patients with CSM from the AOSpine North American study. One hundred ten patients (34%) met inclusion criteria, which were symptomatic CSM, age over 18 years, baseline flexion/extension radiographs, and health-related quality of life (HRQOL) questionnaires (modified Japanese Orthopaedic Association [mJOA] score, Neck Disability Index [NDI], the 36-Item Short Form Health Survey Physical Component Score [SF-36 PCS], and Nurick grade). The mean age was 56.9 ± 12 years, and 42% of patients were women (n = 46). Correlations with HRQOL measures were analyzed for regional (cervical lordosis and cervical sagittal vertical axis) and focal parameters (kyphosis and spondylolisthesis between adjacent vertebrae) in flexion and extension. Baseline dynamic parameters (flexion/extension cone relative to a fixed C-7, center of rotation [COR], and range of motion arc relative to the COR) were also analyzed for correlations with HRQOL measures.

    Results

    At baseline, the mean HRQOL measures demonstrated disability and the mean radiographic parameters demonstrated sagittal malalignment. Among regional parameters, there was a significant correlation between decreased neck flexion (increased C2-7 angle in flexion) and worse Nurick grade (R = 0.189, p = 0.048), with no significant correlations in extension. Focal parameters, including increased C-7 sagittal translation overT-1 (slip), were significantly correlated with greater myelopathy severity (mJOA score, Flexion R = -0.377, p = 0.003; mJOA score, Extension R = -0.261, p = 0.027). Sagittal slip at C-2 and C-4 also correlated with worse HRQOL measures. Reduced flexion/extension motion cones, a more posterior COR, and smaller range of motion correlated with worse general health SF-36 PCS and Nurick grade.

    Conclusions

    Dynamic motion analysis may play an important role in understanding CSM. Focal parameters demonstrated a significant correlation with worse HRQOL measures, especially increased C-7 sagittal slip in flexion and extension. Novel methods of motion analysis demonstrating reduced motion cones correlated with worse myelopathy grades. More posterior COR and smaller range of motion were both correlated with worse general health scores (SF-36 PCS and Nurick grade). To our knowledge, this is the first study to demonstrate correlation of dynamic motion and listhesis with disability and myelopathy in CSM.
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    ItemOpen Access
    Reliability assessment of a novel cervical spine deformity classification system.
    (Journal of neurosurgery. Spine, 2015-12) Ames, Christopher P; Smith, Justin S; Eastlack, Robert; Blaskiewicz, Donald J; Shaffrey, Christopher I; Schwab, Frank; Bess, Shay; Kim, Han Jo; Mundis, Gregory M; Klineberg, Eric; Gupta, Munish; O'Brien, Michael; Hostin, Richard; Scheer, Justin K; Protopsaltis, Themistocles S; Fu, Kai-Ming G; Hart, Robert; Albert, Todd J; Riew, K Daniel; Fehlings, Michael G; Deviren, Vedat; Lafage, Virginie; International Spine Study Group

    Object

    Despite the complexity of cervical spine deformity (CSD) and its significant impact on patient quality of life, there exists no comprehensive classification system. The objective of this study was to develop a novel classification system based on a modified Delphi approach and to characterize the intra- and interobserver reliability of this classification.

    Methods

    Based on an extensive literature review and a modified Delphi approach with an expert panel, a CSD classification system was generated. The classification system included a deformity descriptor and 5 modifiers that incorporated sagittal, regional, and global spinopelvic alignment and neurological status. The descriptors included: "C," "CT," and "T" for primary cervical kyphotic deformities with an apex in the cervical spine, cervicothoracic junction, or thoracic spine, respectively; "S" for primary coronal deformity with a coronal Cobb angle ≥ 15°; and "CVJ" for primary craniovertebral junction deformity. The modifiers included C2-7 sagittal vertical axis (SVA), horizontal gaze (chin-brow to vertical angle [CBVA]), T1 slope (TS) minus C2-7 lordosis (TS-CL), myelopathy (modified Japanese Orthopaedic Association [mJOA] scale score), and the Scoliosis Research Society (SRS)-Schwab classification for thoracolumbar deformity. Application of the classification system requires the following: 1) full-length standing posteroanterior (PA) and lateral spine radiographs that include the cervical spine and femoral heads; 2) standing PA and lateral cervical spine radiographs; 3) completed and scored mJOA questionnaire; and 4) a clinical photograph or radiograph that includes the skull for measurement of the CBVA. A series of 10 CSD cases, broadly representative of the classification system, were selected and sufficient radiographic and clinical history to enable classification were assembled. A panel of spinal deformity surgeons was queried to classify each case twice, with a minimum of 1 intervening week. Inter- and intrarater reliability measures were based on calculations of Fleiss k coefficient values.

    Results

    Twenty spinal deformity surgeons participated in this study. Interrater reliability (Fleiss k coefficients) for the deformity descriptor rounds 1 and 2 were 0.489 and 0.280, respectively, and mean intrarater reliability was 0.584. For the modifiers, including the SRS-Schwab components, the interrater (round 1/round 2) and intrarater reliabilities (Fleiss k coefficients) were: C2-7 SVA (0.338/0.412, 0.584), horizontal gaze (0.779/0.430, 0.768), TS-CL (0.721/0.567, 0.720), myelopathy (0.602/0.477, 0.746), SRS-Schwab curve type (0.590/0.433, 0.564), pelvic incidence-lumbar lordosis (0.554/0.386, 0.826), pelvic tilt (0.714/0.627, 0.633), and C7-S1 SVA (0.071/0.064, 0.233), respectively. The parameter with the poorest reliability was the C7-S1 SVA, which may have resulted from differences in interpretation of positive and negative measurements.

    Conclusions

    The proposed classification provides a mechanism to assess CSD within the framework of global spinopelvic malalignment and clinically relevant parameters. The intra- and interobserver reliabilities suggest moderate agreement and serve as the basis for subsequent improvement and study of the proposed classification.
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    ItemOpen Access
    Stiffness After Pan-Lumbar Arthrodesis for Adult Spinal Deformity Does Not Significantly Impact Patient Functional Status or Satisfaction Irrespective of Proximal Endpoint.
    (Spine, 2017-08) Hart, Robert A; Hiratzka, Jayme; Kane, Marie S; Lafage, Virginie; Klineberg, Eric; Ames, Christopher P; Line, Breton G; Schwab, Frank; Scheer, Justin K; Bess, Shay; Hamilton, David K; Shaffrey, Christopher I; Mundis, Greg; Smith, Justin S; Burton, Douglas C; Sciubba, Daniel M; Deviren, Vedat; Boachie-Adjei, Oheneba; International Spine Study Group

    Study design

    Prospective, multicenter.

    Objective

    To determine if stiffness significantly affects function or satisfaction after pan-lumbar arthrodesis.

    Summary of background data

    The Lumbar Stiffness Disability Index (LSDI) is a validated measure of the effect of lumbar stiffness on functional activities. Data suggests that patients undergoing fusion of the entire lumbar spine are at greatest risk of functional limitations from stiffness.

    Methods

    The LSDI, Short Form 36, Scoliosis Research Society-22, and Oswestry Disability Index were administered preoperatively and at 2-year minimum follow-up to 103 spinal deformity patients from 11 centers. Patients were separated according to the proximal arthrodesis level; upper thoracic (T2-5) to pelvis (UT-Pelvis) or thoraco-lumbar (T10-T12) to pelvis (TL-Pelvis). Outcome scores were compared using Student t test or Tukey-Kramer Honest Significant Difference Analysis of Variance. Regression analysis of final LSDI scores versus Scoliosis Research Society-22 Satisfaction scores was performed.

    Results

    Mean ages, baseline values, and final scores of all outcome parameters were statistically equivalent in the two groups. Final LSDI scores did not change significantly from baseline in the UT-Pelvis (P = 0.478) or TL-Pelvis (P = 0.301) groups. In contrast, highly significant improvements (P ≤ 0.0001) from baseline were seen in both groups for other health-related QoL measures. The 2-year Satisfaction scores were statistically equivalent in the two groups, and the correlation between final LSDI and Satisfaction scores in the entire cohort was not significant (R = 0.013, P = 0.146).

    Conclusion

    Patients undergoing pan-lumbar arthrodesis for adult spinal deformity did not experience substantial increases in disability due to stiffness of the low back, although they did report significant improvements in other health-related QoL measures. Further, LSDI scores did not correlate with patient satisfaction. There were no significant differences in perceived stiffness effects whether arthrodesis stopped in the thoracolumbar or upper thoracic regions. We hope these results will be useful to spine surgeons and patients during preoperative planning and discussions.

    Level of evidence

    2.
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    ItemOpen Access
    Surgical management of complex spinal deformity.
    (The Orthopedic clinics of North America, 2012-01) Erickson, Melissa M; Currier, Bradford L
    Surgical treatment of complex cervical spinal deformities can be challenging operations. Patients often present with debilitating conditions ranging from generalized decreased quality of life to quadriplegia. Surgical treatment can be divided into anterior, posterior, or combined procedures. A thorough understanding of anatomy, pathology, and treatment options is necessary. This article focuses on the surgical treatment of complex spinal deformity.
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    ItemOpen Access
    The effect of posterior polyester tethers on the biomechanics of proximal junctional kyphosis: a finite element analysis.
    (Journal of neurosurgery. Spine, 2017-01) Bess, Shay; Harris, Jeffrey E; Turner, Alexander WL; LaFage, Virginie; Smith, Justin S; Shaffrey, Christopher I; Schwab, Frank J; Haid, Regis W
    OBJECTIVE Proximal junctional kyphosis (PJK) remains problematic following multilevel instrumented spine surgery. Previous biomechanical studies indicate that providing less rigid fixation at the cranial aspect of a long posterior instrumented construct, via transition rods or hooks at the upper instrumented vertebra (UIV), may provide a gradual transition to normal motion and prevent PJK. The purpose of this study was to evaluate the ability of posterior anchored polyethylene tethers to distribute proximal motion segment stiffness in long instrumented spine constructs. METHODS A finite element model of a T7-L5 spine segment was created to evaluate range of motion (ROM), intradiscal pressure, pedicle screw loads, and forces in the posterior ligament complex within and adjacent to the proximal terminus of an instrumented spine construct. Six models were tested: 1) intact spine; 2) bilateral, segmental pedicle screws (PS) at all levels from T-11 through L-5; 3) bilateral pedicle screws from T-12 to L-5 and transverse process hooks (TPH) at T-11 (the UIV); 4) pedicle screws from T-11 to L5 and 1-level tethers from T-10 to T-11 (TE-UIV+1); 5) pedicle screws from T-11 to L-5 and 2-level tethers from T-9 to T-11 (TE-UIV+2); and 6) pedicle screws and 3-level tethers from T-8 to T-11 (TE-UIV+3). RESULTS Proximal-segment range of motion (ROM) for the PS construct increased from 16% at UIV-1 to 91% at UIV. Proximal-segment ROM for the TPH construct increased from 27% at UIV-1 to 92% at UIV. Posterior tether constructs distributed ROM at the UIV and cranial adjacent segments most effectively; ROM for TE-UIV+1 was 14% of the intact model at UIV-1, 76% at UIV, and 98% at UIV+1. ROM for TE-UIV+2 was 10% at UIV-1, 51% at UIV, 69% at UIV+1, and 97% at UIV+2. ROM for TE-UIV+3 was 7% at UIV-1, 33% at UIV, 45% at UIV+1, and 64% at UIV+2. Proximal segment intradiscal pressures, pedicle screw loads, and ligament forces in the posterior ligament complex were progressively reduced with increasing number of posterior tethers used. CONCLUSIONS Finite element analysis of long instrumented spine constructs demonstrated that posterior tethers created a more gradual transition in ROM and adjacent-segment stress from the instrumented to the noninstrumented spine compared with all PS and TPH constructs. Posterior tethers may limit the biomechanical risk factor for PJK; however, further clinical research is needed to evaluate clinical efficacy.