Abstract Background Context Patients with degenerative lumbar stenosis (DLS) adopt a forward flexed posture in an attempt to decompress neural elements. The relationship between sagittal alignment ...and severity of lumbar stenosis has not previously been studied. Purpose We hypothesized that patients with increasing radiological severity of lumbar stenosis will exhibit worsening sagittal alignment. Study Design This is a cross-sectional study. Patient Sample Our sample consists of patients who have DLS. Outcome Measures Standing pelvic, regional, lower extremity and global sagittal alignment, and health-related quality of life (HRQoL) were the outcome measures. Methods Patients with DLS were identified from a retrospective clinical database with corresponding full-body stereoradiographs. Exclusion criteria included coronal malalignment, prior spine surgery, spondylolisthesis>Grade 1, non-degenerative spinal pathology, or skeletal immaturity. Central stenosis severity was graded on axial T2-weighted magnetic resonance imaging (MRI) from L1–S1. Foraminal stenosis and supine lordosis was graded on sagittal T1-weighted images. Standing pelvic, regional, lower extremity, and global sagittal alignment were measured using validated software. The HRQoL measures were also analyzed in relation to severity of stenosis. Results A total of 125 patients were identified with DLS on appropriate imaging. As central stenosis grade increased, patients displayed significantly increasing standing T1 pelvic angle, pelvic tilt, sagittal vertical axis, and pelvic incidence-lumbar lordosis (p<.05). No significant difference wasfound in pelvic incidence, supine lordosis, thoracic kyphosis, or T1 spinopelvic inclination between central stenosis groups. Despite similar supine lordosis between stenosis groups, patients with Grades 2 and 3 stenosis had less standing lordosis, suggesting antalgic posturing. Upper lumbar (L1–L3) stenosis predicted worse alignment than lower lumbar (L4–S1) stenosis. Increasing severity of foraminal stenosis was associated with reduced lumbar lordosis; however, no significant postural difference in lordosis, thoracolumbar, or lower extremity compensatory mechanisms were noted between foraminal stenosis groups. Stenosis grading did not predict worsening HRQoLs in central or foraminal stenosis. Conclusions Severity of central lumbar stenosis as graded on MRI correlates with severity of sagittal malalignment. These findings support theories of sagittal malalignment as a compensatory mechanism for central lumbar stenosis.
Changes in spinopelvic and lower extremity alignment between standing and relaxed sitting have important clinical implications with regard to stability of total hip arthroplasty. This study aimed to ...analyze the effect of body mass index (BMI) on lumbopelvic alignment and motion at the hip joint.
A retrospective review of patients who underwent full-body stereoradiographs in standing and relaxed sitting for total hip arthroplasty planning was conducted. Spinopelvic parameters measured included spinopelvic tilt (SPT), pelvic incidence (PI), lumbar lordosis (LL), PI minus LL (PI-LL), proximal femoral shaft angle (PFSA), and standing-to-sitting hip range of motion. Propensity score matching controlled for age, gender, PI, and hip ostoarthritis grade. Patients were stratified into normal (NORMAL; BMI, 18.5-24.9), overweight (OW; 25.0-29.9), and obese (OB; 30.0-34.9) groups. Alignment parameters were compared using one-way analysis of variance.
There were 84 patients in each group after propensity score matching. Standing alignment between BMI groups was similar for all parameters (P > .05) except for PFSA (P < .001). Significant differences were noted for sitting alignment between patients who are NORMAL, OW, and OB in: SPT (P = .007), PI-LL (P = .018), and LL (P = .029). PFSA between groups was not significantly different (P > .05). Significant differences were found for sitting-to-standing alignment across groups in PFSA change (P < .001), SPT change (P = .006), PI-LL change (P = .005), LL change (P = .037), and hip flexion (P < .001).
Significant differences in sitting and standing-to-sitting change in lumbopelvic alignment based on BMI suggest obese patients recruit more posterior spinopelvic tilt when sitting to compensate for soft-tissue impingement that occurs anterior to the hip joint and limiting hip flexion.
Abstract Background Although cervical spondylotic myelopathy (CSM) can be devastating, its relative impact on general health remains unclear. Patient responses to the SF-36 PCS/MCS were compared ...between CSM and other diseases to evaluate their respective impacts on quality of life. Objective Compare SF-36 PCS/MCS scores in CSM to population and disease-specific norms. Methods Retrospective analysis of a prospective, multi-center AOSpine North American CSM Study database. Inclusion criteria were symptomatic disease, age>18, cord compression on MRI or CT myelography, and baseline SF-36 values. SF-36 PCS/MCS in CSM were compared to national normative values and disease-specific norms using student's t-test. ANOVA was used to assess differences across age groups and offsets from age-matched controls. Threshold for significance was p<0.05. Results 285 patients met inclusion criteria. Mean age was 56.6+12.0 years with male predominance (60%). SF-36 scores revealed significant baseline disability (PCS 34.5+9.8; MCS 41.5± 14.4). While there were no differences across age groups, when compared to age-matched normative data, younger patients had a larger PCS offset than older patients. CSM caused worse physical disability than most diseases except heart failure. Only back pain/sciatica induced worse mental disability. Conclusion CSM affects quality of life to an extent greater than diabetes or cancer. Although mean impact of CSM does not vary with age, younger patients suffer from greater differences in baseline function. This study highlights the impact of myelopathy on patient function, particularly among younger age groups, and suggests that CSM merits similar caliber of healthy policy attention as more well-studied diseases.
Background Adult spinal deformity is a prevalent cause of pain and disability. Established measures of sagittal spinopelvic alignment such as sagittal vertical axis and pelvic tilt can be modified by ...postural compensation, including pelvic retroversion, knee flexion, and the use of assistive devices for standing. We introduce the T1 pelvic angle, a novel measure of sagittal alignment that simultaneously accounts for both spinal inclination and pelvic retroversion. The purpose of this study was to investigate the relationship of the T1 pelvic angle and other established sagittal alignment measures and to correlate these parameters with health-related quality-of-life measures. Methods This is a multicenter, prospective, cross-sectional analysis of consecutive patients with adult spinal deformity. Inclusion criteria were adult spinal deformity, an age of greater than eighteen years, and any of the following: scoliosis, a Cobb angle of ≥20°, sagittal vertical axis of ≥5 cm, thoracic kyphosis of ≥60°, and pelvic tilt of ≥25°. Clinical measures of disability included the Oswestry Disability Index (ODI), Scoliosis Research Society (SRS)-22, and Short Form-36 (SF-36) questionnaires. Results Five hundred and fifty-nine consecutive patients with adult spinal deformity (mean age, 52.5 years) were enrolled. The T1 pelvic angle correlated with the sagittal vertical axis (r = 0.837), pelvic incidence minus lumbar lordosis (r = 0.889), and pelvic tilt (0.933). Categorizing the patients by increasing T1 pelvic angle (<10°, 10° to 20°, 21° to 30°, and >30°) revealed a significant and progressive worsening in health-related quality of life (p < 0.001 for all). The T1 pelvic angle and sagittal vertical axis correlated with the ODI (0.435 and 0.455), SF-36 Physical Component Summary (–0.445 and –0.458), and SRS (–0.358 and –0.383) (p < 0.001 for all). Utilizing a linear regression analysis, a T1 pelvic angle of 20° corresponded to a severe disability (an ODI of >40), and the meaningful change in T1 pelvic angle corresponding to one minimal clinically important difference was 4.1° on the ODI. Conclusions The T1 pelvic angle correlates with health-related quality of life in patients with adult spinal deformity. The T1 pelvic angle is related to both pelvic tilt and sagittal vertical axis; however, unlike sagittal vertical axis, it does not vary on the basis of the extent of pelvic retroversion or patient support in standing. Since the T1 pelvic angle is an angular and not a linear measure, it does not require calibration of the radiograph. Thus, the T1 pelvic angle measures sagittal deformity independent of many postural compensatory mechanisms, and it can be useful as a preoperative planning tool, with a target T1 pelvic angle of <14°. Level of Evidence Diagnostic Level II . See Instructions for Authors for a complete description of levels of evidence.
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