Sagittal spino-pelvic alignment in adults: The Wakayama Spine Study

Hip-spine parameters change with increasing age

Aims

Spinopelvic pathology increases the risk for instability following total hip arthroplasty (THA), yet few studies have evaluated how pathology varies with age or sex. The aims of this study were: 1) to report differences in spinopelvic parameters with advancing age and between the sexes; and 2) to determine variation in the prevalence of THA instability risk factors with advancing age.

Methods

A multicentre database with preoperative imaging for 15,830 THA patients was reviewed. Spinopelvic parameter measurements were made by experienced engineers, including anterior pelvic plane tilt (APPT), spinopelvic tilt (SPT), sacral slope (SS), lumbar lordosis (LL), and pelvic incidence (PI). Lumbar flexion (LF), sagittal spinal deformity, and hip user index (HUI) were calculated using parameter measurements.

Results

With advancing age, patients demonstrate increased posterior APPT, decreased standing LL, decreased LF, higher pelvic incidence minus lumbar lordosis (PI-LL) mismatch, higher prevalence of abnormal spinopelvic mobility, and higher HUI percentage. With each decade, APPT progressed posteriorly 2.1°, LF declined 6.0°, PI-LL mismatch increased 2.9°, and spinopelvic mobility increased 3.8°. Significant differences were found between the sexes for APPT, SPT, SS, LL, and LF, but were not felt to be clinically relevant.

Conclusion

With advancing age, spinopelvic biomechanics demonstrate decreased spinal mobility and increased pelvic/hip mobility. Surgeons should consider the higher prevalence of instability risk factors in elderly patients and anticipate changes evolving in spinopelvic biomechanics for young patients.

Relationship of total sagittal spinal alignment index of thoracic kyphosis and lumbar lordosis with physical function in community-dwelling older adults

BACKGROUND

Overall spinal curvature is evaluated by calculating the difference between the angles of lumbar lordosis (LL) and thoracic kyphosis (TK) and is expressed as LL minus TK (LL-TK). It is unclear whether LL-TK is associated with physical function in community-dwelling older adults and whether it is more relevant than TK or LL alone.

OBJECTIVE

This study aimed to identify whether LL-TK is associated with physical function in community-dwelling older adults, and whether it is strongly associated than TK or LL alone.

METHODS

The participants comprised 1,674 community-dwelling older adults who underwent physical assessments (women, n = 1,099; mean age, 67.4 ± 5.3 years). As spinal alignment indices, TK and LL were measured using skin surface methods, and LL-TK was calculated as the difference between them. Decreased LL-TK indicated increased overall spinal curvature. Physical function was determined by measuring single-leg standing, five-times chair-stand, and usual gait speed. Stepwise multiple regression analyses were performed with each physical function as the dependent variable and spinal alignment indices as the independent variables, with adjustments.

RESULTS

Multiple regression analyses showed that single-leg standing (β = 0.092, 95% confidence interval [CI] = 0.071 to 0.214, p < .001) and five-times chair-stand (β=-0.142, 95% CI = -0.037 to -0.019, p < .001) were significantly associated with LL-TK, but not LL. Both LL-TK (β = 0.121, 95% CI = 0.001 to 0.004, p < .001) and LL (β = 0.087, 95% CI = 0.001 to 0.003, p = .003) were significant determinants of usual gait speed.

CONCLUSIONS

This study showed that decreased LL-TK may be associated with poor physical function. This association may be stronger than that observed for TK or LL alone.

Osteoporosis, spinal degenerative disorders, and their association with low back pain, activities of daily living, and physical performance in a general population

Osteoporosis, vertebral fractures, and spinal degenerative diseases are common conditions that often coexist in older adults. This study aimed to determine the factors influencing low back pain and its impact on activities of daily living (ADL) and physical performance in older individuals with multiple comorbidities. This cross-sectional study was part of a large-scale population-based cohort study in Japan, involving 1009 participants who underwent spinal magnetic resonance imaging (MRI) to assess cervical cord compression, radiographic lumbar spinal stenosis, and lumbar disc degeneration. Vertebral fractures in the thoracolumbar spine were evaluated using sagittal MRI with a semi-quantitative method. Bone mineral density was measured using dual-energy X-ray absorptiometry. Low back pain, Oswestry Disability Index (ODI), and physical performance tests, such as one-leg standing time, five times chair-stand time, maximum walking speed, and maximum step length, were assessed. Using clinical conditions as objective variables and image evaluation parameters as explanatory variables, multiple regression analysis showed that vertebral fractures were significantly associated with low back pain and ODI. Vertebral fractures and osteoporosis significantly impacted physical performance, whereas osteoporosis alone did not affect low back pain or ODI. Our findings contribute to new insights into low back pain and its impact on ADL and physical performance.

Defining Age-Adjusted PI-LL Targets for Surgical Realignment in Adult Degenerative Scoliosis: A Retrospective Cohort Study

Objectives: The purpose of this study was to investigate postoperative pelvic incidence minus lumbar lordosis mismatch (PI-LL) and health-related quality of life (HRQOL) outcomes to determine age-adjusted PI-LL targets. Method: The dataset encompassed a range of variables, including age, sex, body mass index, Charlson comorbidity index, presence of osteopenia, hospital stay, operative duration, blood loss, American Society of Anesthesiologists score, number of fusion levels, lumbar lordosis, sagittal vertical axis, pelvic incidence, and PI-LL. The non-linear relationship between PI-LL and clinical outcomes was examined using a curve analysis, with adjustments made for potential confounding variables. Upon identification of a non-linear relationship, a two-piecewise regression model was employed to determine the threshold effect. Results: A total of 280 patients were enrolled. In the fully adjusted model, the optimal PI-LL target for patients aged 45-54 years old was PI-LL < 10°, the optimal target for patients aged 55-74 was 10-20°, and the optimal target for patients older than 75 years was more suitable for PI-LL > 20°. In the curve-fitting graph, it could be seen that the relationship between PI-LL and HRQOL outcomes was not linear in each age group. The peaks of the curves within each group occurred at different locations. Higher and lower thresholds for optimal surgical goals were determined using the two-piecewise regression model from the SRS-22 score and the ODI score. Conclusions: This study showed that the optimal PI-LL after corrective surgery in adult degenerative scoliosis patients should be adjusted according to age.

Two Methods of Forward Head Posture Assessment: Radiography vs. Posture and Their Clinical Comparison

Background: Forward head posture (FHP) and altered cervical lordotic curvatures are common spine displacements often associated with neck pain and disability. Two primary categories for determining FHP exist: radiographic and postural measurements. Methods: This study investigated the correlation between the craniovertebral angle (CVA), the radiographically measured C2-C7 sagittal vertical axis (SVA), and cervical lordosis (absolute rotation angle: ARA C2-C7) in a sample of participants with chronic myofascial pain (CMP). In 120 participants, we performed both a postural measurement of the CVA and a lateral cervical radiograph, where the C2-C7 SVA and ARA C2-C7 were measured. A linear-regression R2 value to assess the correlation between the CVA, C2-C7 SVA, and ARA C2-C7 was sought. Results: A statistically significant weak linear fit was identified (Spearman's r = 0.549; R2 = 0.30, p < 0.001) between the CVA and C2-C7 SVA, having considerable variation between the two measures. A statistically significant linear fit (very weak) was identified for the lordosis ARA C2-C7 and the CVA: Spearman's r = 0.524; R2 = 0.275; p < 0.001. A value of 50° for the CVA corresponded to a value of 20 mm for the C2-C7 SVA on an X-ray. Conclusion: While the CVA and radiographic C2-C7 SVA are weakly correlated in an individual, they seem to represent different aspects of sagittal cervical balance. The CVA cannot replace radiographically measured cervical lordosis. We recommend that more emphasis be given to radiographic measures of sagittal cervical alignment than the CVA when considering patient interventions.

Male-female disparity in clinical features and significance of mild vertebral fractures in community-dwelling residents aged 50 and over

This investigation examined the clinical implications of mild vertebral fractures in older community-dwelling residents. Focusing on the locomotion health of older individuals, the earlier reported Obuse study enrolled 415 randomly sampled Japanese residents aged between 50 and 89 years, 411 of whom underwent X-ray evaluations for pre-existing vertebral fractures. A blinded assessment of vertebral fractures based on Genant's criteria was conducted on the T5-L5 spine for rating on a severity scale. Grade 1 mild fractures were not linked to age in males, but increased with aging in females. Female participants had fewer Grade 1 and 2 fractures (P = 0.003 and 0.035, respectively) but more Grade 3 fractures (P = 0.013) than did males independently of age (Grade 1, 2, and 3: 25%, 16%, and 9% in females and 40%, 22%, and 6% in males, respectively). Weak negative correlations were observed between the number of fractures and bone mineral density in females for all fracture grades (Spearman's rho: 0.23 to 0.36, P < 0.05). Our study showed that Grade 1 mild vertebral fractures in males lacked pathological significance, while in females they potentially indicated fragility fractures and were related to poor lumbopelvic alignment.

Sagittal Alignment in the Degenerative Lumbar Spine: Surgical Planning

➤ Sagittal alignment of the spine has gained attention in the field of spinal deformity surgery for decades. However, emerging data support the importance of restoring segmental lumbar lordosis and lumbar spinal shape according to the pelvic morphology when surgically addressing degenerative lumbar pathologies such as degenerative disc disease and spondylolisthesis.➤ The distribution of caudal lordosis (L4-S1) and cranial lordosis (L1-L4) as a percentage of global lordosis varies by pelvic incidence (PI), with cephalad lordosis increasing its contribution to total lordosis as PI increases.➤ Spinal fusion may lead to iatrogenic deformity if performed without attention to lordosis magnitude and location in the lumbar spine.➤ A solid foundation of knowledge with regard to optimal spinal sagittal alignment is beneficial when performing lumbar spinal surgery, and thoughtful planning and execution of lumbar fusions with a focus on alignment may improve patient outcomes.

Factors associated with cam deformity in Japanese local residents

Femoroacetabular impingement has increasingly been recognized as a cause of primary hip osteoarthritis; however, its epidemiological indications remain unclear. We aimed to clarify the epidemiological indications and factors associated with cam deformity in a large-scale population-based cohort in Japan. Overall, 1480 participants (2960 hips) (491 men, 989 women; mean age, 65.3 years) analyzed in the third survey of the Research on Osteoarthritis/Osteoporosis Against Disability study were included. The α angle and spinopelvic parameters (lumbar lordosis, sacral slope, pelvic tilt, and pelvic incidence) were radiographically measured. Cam deformity was defined as α angle ≥ 60°. Overall, the cam deformity prevalence was 147/2960 (5.0%). Cam deformity prevalence tended to increase with age; in the univariate analysis, a higher percentage of men was observed in the group with cam deformity than in the group without it. No relationship was observed between cam deformity and hip pain. Factors associated with α angle were examined via multiple regression analysis for each gender; α angle was significantly associated with age and BMI in each gender. The α angle and PT were correlated in women. Thus, α angle and cam deformity prevalence increase with age in Japanese individuals. Accordingly, cam deformity can be considered a developmental disease.

Thoracolumbar Sagittal Shape Varies With Pelvic Morphology and Aging

STUDY DESIGN

Retrospective study of a multicenter prospective database.

OBJECTIVE

The objective of this study was to determine the organization and correlations between different spinal segments according to pelvic incidence (PI) and age.

SUMMARY OF BACKGROUND DATA

When planning surgery for the correction of adult spinal deformities, considering lumbar lordosis (LL) as a uniform segment is an approximation that can lead to planning errors.

MATERIALS AND METHODS

Radiographs of 1540 subjects were analyzed and divided into three PI groups: low <45, intermediate 45 to 60, high >60, and stratified by age (<45, 45-70, and >70 yr). The different segments of L1-L4 proximal lumbar lordosis (PLL), L4-S1 distal lumbar lordosis (DLL), and T10-L1 thoracolumbar junction (TLJ) were analyzed.

RESULTS

The mean age was 53.5 years (SD=17, minimum=20, maximum=93). There was a significant correlation between thoracic kyphosis T5-T12 and TLJ segment T10-L1 ( r =0.581, P <0.001). Only the L1-L4 PLL segment correlated with PI ( r =0.47, P <0.001). The T10-L1 TLJ segment was constant regardless of age or PI groups considered (mean=-8, SD=9). PLL did not vary with aging but differed according to PI. The DLL showed significant differences between age and PI groups but without a significant correlation between PI and DLL.

CONCLUSIONS

Pelvic morphology is known to determine the curvatures of the spine, however, the distribution of LL is not homogeneous. Our study provided a normative value reference and showed that T10-L1 is constant regardless of age or PI.

LEVEL OF EVIDENCE

III.

Prevalence of global spinal malalignment and the influence on LBP and HR-QOL in a healthy, nonelderly population. A cross sectional analysis, including bone mineral density, skeletal muscle mass index, and back muscle extensor strength

Background

In healthy, nonelderly populations, prevalence of 3 modifiers of global spinal malalignment (GS-MalAlign) (PT ≧20°, PI-LL≧10°, SVA≧40 mm) remains unknown. The clinical significance has not been determined. The purposes are to disclose the prevalence of the 3 modifiers of GS-MalAlign, and evaluate the influence on LBP, and HR-QOL related to bone mineral density (BMD), skeletal muscle mass index (SMI), and back muscle extensors strength (BMES) in a healthy, nonelderly population.

Methods

A mono-centric, cross-sectional survey. Three hundred and 2 participants (18< age <65 years) without ADL disturbance were consecutively enrolled. Sagittal parameters of the spine and the pelvis were measure on whole spine radiograms. BMD and SMI were determined using DEXA. BMES was defined as a maximum extension force at the T4 to T7 level and measured by a strain-gauge dynamotor. LBP was checked through interview. HR-QOL was ascertained by score of Medical Outcome Study Short-Form 36-Health Survey (SF-36v2).

Results

The final analysis could be done in 84 females and 179 males. PT≧20°, PI-LL≧10°, and SVA≧40 mm were found in 12% (31/263), 11% (31/263), and 6% (16/263), and each mean value was 25.0 ± 4.0°, 15.3 ± 5.9°, and 52.7 ± 12.2 mm (Mean ± S.D.). Prevalence of LBP was significantly higher in the participants with PI-LL≧10° than with PI-LL<10°; 43% (12/28) versus 21% (49/235) (p<.05). PI-LL≧10° only had an association with LBP (OR: 3.0435, 95% CI, 1.1378-8.141, p<.05). Four 2% of participants (4/263) associated with all 3 modifiers had LBP and a significantly lower mental component summary score of SF-36v2 (p<.05).

Conclusions

Some of individuals are associated with GS-MalAlign even in healthy, nonelderly populations. There is a possibility that PI-LL ≧10° results in LBP within a degree of no ADL disturbance, and it is speculated that coexistence of all 3 modifiers of GS-MalAlign would lead to a poor mental HR-QOL.

Differences in imaging and clinical characteristics are associated with higher rates of decompression-fusion versus decompression-alone in women compared to men for lumbar degenerative spondylolisthesis

PURPOSE

The goals were to ascertain if differences in imaging/clinical characteristics between women and men were associated with differences in fusion for lumbar degenerative spondylolisthesis.

METHODS

Patients had preoperative standing radiographs, CT scans, and intraoperative fluoroscopic images. Symptoms and comorbidity were obtained from patients; procedure (fusion-surgery or decompression-alone) was obtained from intraoperative records. With fusion surgery as the dependent variable, men and women were compared in multivariable logistic regression models with clinical/imaging characteristics as independent variables. The sample was dichotomized, and analyses were repeated with separate models for men and women.

RESULTS

For 380 patients (mean age 67, 61% women), women had greater translation, listhesis angle, lordosis, and pelvic incidence, and less diastasis and disc height (all p ≤ 0.03). The rate of fusion was higher for women (78% vs. 65%; OR 1.9, p = 0.008). Clinical/imaging variables were associated with fusion in separate models for men and women. Among women, in the final multivariable model, less comorbidity (OR 0.5, p = 0.05), greater diastasis (OR 1.6, p = 0.03), and less anterior disc height (OR 0.8, p = 0.0007) were associated with fusion. Among men, in the final multivariable model, opioid use (OR 4.1, p = 0.02), greater translation (OR 1.4, p = 0.0003), and greater diastasis (OR 2.4, p = 0.0002) were associated with fusion.

CONCLUSIONS

There were differences in imaging characteristics between men and women, and women were more likely to undergo fusion. Differences in fusion within groups indicate that decisions for fusion were based on composite assessments of clinical and imaging characteristics that varied between men and women.

Do Age-Related Variations Of Sagittal Alignment Rely On SpinoPelvic Organization? An Observational Study Of 1540 Subjects

STUDY DESIGN

Descriptive radiographic analysis of a prospective multi-center database.

OBJECTIVE

This study aims to provide normative values of spinopelvic parameters and their correlations according to age and pelvic incidence (PI) of subjects without spinal deformity.

METHODS

After Institutional Review Board (IRB) approval, 1540 full spine radiographs were analyzed. Subjects were divided into 3 groups of PI: low PI < 45°, intermediate PI 45-60°, high PI > 60°, and then stratified by age (20-34, 35-49, 50-64, > 65 Y.O). Pelvic and spinal parameters were measured. Statistical analysis between parameters was performed using Bayesian inference and correlation.

RESULTS

Mean age was 53.5 years (845 females, 695 males, range 20-93 years).In low PI group, lumbar lordosis (LL) decrease was mainly observed in the 2 younger age groups.In medium and high PI groups, loss of lordosis was linear during aging and occurred mainly on the distal arch of lordosis. Moderate PI group had a stable lordosis apex and thoracolumbar inflection point. High PI group had a stable thoracolumbar inflection point and a more distal lordosis apex in elderly subjects.For all subjects, kyphosis and pelvic tilt (PT) increased with age.There was a constant chain of correlation between PI and age groups. Proximal lumbar lordosis (PLL) was correlated with kyphosis and sagittal vertical axis (SVA C7), while the distal lumbar lordosis (DLL) was correlated with PI and PT.

CONCLUSION

This study provides a detailed repository of sagittal spinopelvic parameters normative values with detailed analysis of segmental kyphosis and lordosis distribution according to gender, age, and PI.

Spinopelvic Alignment: Importance in Spinal Pathologies and Realignment Strategies

Sagittal spinal malalignment can lead to pain, decreased function, dynamic imbalance, and compromise of patient-reported health status. The goal of reconstructive spine surgery is to restore spinal alignment parameters, and an understanding of appropriate patient-specific alignment is important for surgical planning and approaches. Radiographic spinopelvic parameters are strongly correlated with pain and function. The relationship between spinopelvic parameters and disability in adult spinal deformity patients is well-established, and optimal correction of sagittal alignment results in improved outcomes regarding patient health status and mechanical complications of surgery.

Racial differences in whole-body sagittal alignment between Asians and Caucasians based on international multicenter data

PURPOSE

To examine inherent differences adjusted for age and clinical score in whole-body sagittal (WBS) alignment involving the lower extremities between Asians and Caucasians, and to determine the relationship between age and WBS parameters by race and sex.

METHODS

A total of 317 individuals consisting of 206 Asians and 111 Caucasians participated. WBS parameters including C2-7 lordotic angle, lower lumbar lordosis (lower LL, L4-S), pelvic incidence (PI), pelvic thickness, knee flexion (KF), sagittal vertical axis (SVA), and T1 pelvic angle (TPA) were evaluated radiologically. Propensity score-matching adjustments for age and the Oswestry Disability Index scores for comparative analysis between the two race cohorts and correlation analysis between age and WBS parameters for all subjects by race and sex were conducted.

RESULTS

The comparative analysis included 136 subjects (age: Asians 41.1 ± 13.5, Caucasians 42.3 ± 16.2 years, p = 0.936). Racial differences in WBS parameters were observed in C2-7 lordotic angle (-1.8 ± 12.3 vs. 6.3 ± 12.2 degrees, p = 0.001), and lower LL (34.0 ± 6.6 vs. 38.0 ± 6.1 degrees, p < .001). In correlation analysis with age, moderate or more significant correlations with age were found in KF for all groups, and in SVA and TPA for females of both racial groups. Age-related changes in pelvic parameters of PI and pelvic thickness were more significant in Caucasian females.

CONCLUSION

Analysis of the correlation between age and WBS parameters suggested that age-related WBS changes vary between races and should be considered during corrective spinal surgery.

Reliability and validity of gait dynamic balance assessment in adult spinal deformity patients using a two-point trunk motion measuring device

BACKGROUND CONTEXT

Adult spinal deformity (ASD) patients often complain of walking discomfort. However, dynamic balance evaluation methods of gait in ASD have not been well established.

DESIGN

Case series study.

PURPOSE

Characterize the gait of ASD patients using a novel two-point trunk motion measuring device.

PATIENT SAMPLE

Sixteen ASD patients scheduled for surgery and 16 healthy control subjects.

OUTCOME MEASURES

Trunk swing width and track length of the upper back and sacrum.

METHODS

Gait analysis was performed using a two-point trunk motion measuring device on 16 ASD patients and 16 healthy control subjects. Three measurements were taken for each subject, and the coefficient of variation was determined to compare measurement accuracy between the ASD and control groups. Trunk swing width and track length were measured in three dimensions for comparisons between the groups. The relationship among output indices, sagittal spinal alignment parameters, and quality of life (QOL) questionnaire scores was examined as well.

RESULTS

No significant difference was found for the precision of the device between the ASD and control groups. Compared with controls, the walking style of ASD patients tended to have larger right-left swing of the trunk (+14.0 cm and +23.3 cm at the sacrum and upper back, respectively), larger horizontal plane movement of the upper body (+36.4 cm), less vertical movement (-5.9 cm and -8.2 cm up-down swing at the sacrum and upper back, respectively), and longer gait cycle (+0.13 sec). Regarding QOL in ASD patients, greater right-left/front-back swing of the trunk, greater movement in the horizontal plane, and longer gait cycle were associated with lower QOL scores. Conversely, greater vertical movement was associated with higher QOL.

CONCLUSIONS

ASD patients had unique gait characteristics, the intensity of which were associated with diminished QOL. The two-point trunk motion measuring device may be reliable and useful for the clinical assessment of balance during gait in ASD patients.

Sagittal Spinal Alignment in People with Chronic Spinal Cord Injury and Normal Individual: A Comparison Study Using 3D Ultrasound Imaging

The aim of this study was to compare the sagittal spinal alignment of people with chronic spinal cord injury (SCI) with normal individuals and to determine whether transcutaneous electrical spinal cord stimulation (TSCS) could cause a change in the thoracic kyphosis (TK) and lumbar lordosis (LL) to re-establish normal sagittal spinal alignment. A case series study was conducted, wherein twelve individuals with SCI and ten neurologically intact subjects were scanned using 3D ultrasonography. In addition, three people with SCI having complete tetraplegia participated further to receive a 12-week treatment (TSCS with task-specific rehabilitation) after evaluation of sagittal spinal profile. Pre- and post-assessments were conducted to evaluate the differences in sagittal spinal alignment. The results showed that the TK and LL values for a person with SCI in a dependent seated posture were greater than those of normal subjects for: standing (by TK: 6.8° ± 1.6°; LL: 21.2° ± 1.9°), sitting straight (by TK: 10.0° ± 4.0°; LL: 1.7° ± 2.6°), and relaxed sitting (by TK: 3.9° ± 0.3°; LL: 7.7° ± 1.4°), respectively, indicating an increased risk for spinal deformity. In addition, TK decreased by 10.3° ± 2.3° after the TSCS treatment, showing a reversible change. These results suggest that the TSCS treatment could be used to restore normal sagittal spinal alignment for individuals with chronic SCI.

Association between modic changes, disc degeneration, and pelvic incidence-lumbar lordosis mismatch in a large population based cohort: the Wakayama spine study

PURPOSE

Sagittal plane alignment is crucial for treating spinal malalignment and low back pain. Pelvic incidence-lumbar lordosis (PI-LL) mismatch is commonly used to evaluate clinical outcomes in patients with sagittal malalignment. The association between PI-LL mismatch and changes surrounding the intervertebral disc is very important to understand the compensatory mechanisms involved. This study aimed to examine the association between PI-LL mismatch and magnetic resonance imaging (MRI) changes surrounding the intervertebral disc in a large population-based cohort.

METHODS

We evaluated participants from the second Wakayama Spine Study, recruiting the general population aged 20 years or older, irrespective of sex, who were registered residents in one region in 2014. In total, 857 individuals underwent an MRI of the whole spine; however, 43 MRI results were not included due to incomplete or inadequate quality images. PI-LL mismatch was defined as > 11°. We compared the MRI changes, such as Modic change (MC), disc degeneration (DD), and high-intensity zones (HIZ), between PI-LL mismatch and non-PI-LL mismatch groups. Multivariate logistic regression analysis was conducted to determine the association between the MRI changes and PI-LL mismatch with adjustment for age, sex, and body mass index in the lumbar region and at each level.

RESULTS

A total of 795 participants (243 men, 552 women, mean age 63.5 ± 13.1 years old) were evaluated; 181 were included in the PI-LL mismatch group. MC and DD in the lumbar region were significantly higher in the PI-LL mismatch group. MC in the lumbar region was significantly associated with PI-LL mismatch (odds ratio (OR); 1.81, 95% confidence interval (CI) 1.2-2.7). MC at each level was significantly associated with PI-LL mismatch (OR; 1.7-1.9, 95%CI 1.1-3.2), and DD at L1/2, L3/4, and L4/5 was associated with PI-LL mismatch (OR; 2.0- 2.4. 95%CI 1.2-3.9).

CONCLUSION

MC and DD were significantly associated with PI-LL mismatch. Therefore, profiling MC may be helpful in improving the targeted treatment of LBP associated with the adult spinal deformity.

The effect of ethnicity on the age-related changes of spinopelvic characteristics: a systematic review

Aims

Spinopelvic characteristics influence the hip’s biomechanical behaviour. However, to date there is little knowledge defining what ‘normal’ spinopelvic characteristics are. This study aims to determine how static spinopelvic characteristics change with age and ethnicity among asymptomatic, healthy individuals.

Methods

This systematic review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines to identify English studies, including ≥ 18-year-old participants, without evidence of hip or spine pathology or a history of previous surgery or interventional treatment, documenting lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI). From a total of 2,543 articles retrieved after the initial database search, 61 articles were eventually selected for data extraction.

Results

When all ethnicities were combined the mean values for LL, SS, PT, and PI were: 47.4° (SD 11.0°), 35.8° (SD 7.8°), 14.0° (SD 7.2°), and 48.8° (SD 10°), respectively. LL, SS, and PT had statistically significant (p < 0.001) changes per decade at: −1.5° (SD 0.3°), −1.3° (SD 0.3°), and 1.4° (SD 0.1°). Asian populations had the largest age-dependent change in LL, SS, and PT compared to any other ethnicity per decade at: −1.3° (SD 0.3°) to −0.5° (SD 1.3°), –1.2° (SD 0.2°) to −0.3° (SD 0.3°), and 1.7° (SD 0.2°) versus 1.1° (SD 0.1°), respectively.

Conclusion

Ageing alters the orientation between the spine and pelvis, causing LL, SS, and PT to modify their orientations in a compensatory mechanism to maintain sagittal alignment for balance when standing. Asian populations have the largest degree of age-dependent change to their spinopelvic parameters compared to any other ethnicity, likely due to their lower PI.

Cite this article: Bone Joint Res 2023;12(4):231–244.

The prevalence of locomotive syndrome and its associated factors in patients with Type 2 diabetes mellitus

OBJECTIVES

We investigated the prevalence of locomotive syndrome (LS) and related musculoskeletal diseases [osteoarthritis (OA), lumbar spondylosis, and spinal alignment] in Type 2 diabetes mellitus (DM) patients.

METHODS

Clinical data were collected from 101 patients (55 males; 46 females) admitted to our hospital for diabetes education from October 2018 to April 2021. Patients underwent full-spine and whole-legs standing radiography and physical measurements (10-m walking and grip strength tests and three LS risk tests).

RESULTS

The estimated prevalence of LS was 86.1% (Stage 1: 44.5%, Stage 2: 41.6%), lumbar spondylosis was 11.9%, and hip, knee, and ankle OA were 16.9%, 51.5%, and 12.9%, respectively. Multiple logistic regression analysis identified grip strength [odds ratio (OR) = 0.89, confidence interval (CI) = 0.83-0.94], diabetic retinopathy (OR = 5.85, CI = 1.64-20.78), knee OA (OR = 3.34, CI = 1.11-10.02), and a sagittal vertical axis >40 mm (OR = 3.42, CI = 1.13-10.39) as significantly associated risk factors for worsening LS in Type 2 DM patients.

CONCLUSIONS

This study clarified the epidemiological indicators of LS and associated factors in DM patients. Exercise therapy and DM management are effective strategies to reduce the occurrence and progression of LS.

Impact of Spino-Pelvic Parameters on the Prediction of Lumbar and Thoraco-Lumbar Segment Angles in the Supine Position

Background: The correction of malposition according to vertebral fractures is difficult because the alignment at the time before the fracture is unclear. Therefore, we investigate whether the spinal alignment can be determined by the spino-pelvic parameters. Methods: Pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), adjacent endplate angles (EPA), age, sex, body weight, body size, BMI, and age were used to predict mono- and bisegmental EPA (mEPA, bEPA) in the supine position using linear regression models. This study was approved by the Ethics Committee of the Medical Association of Saxony-Anhalt Germany on 20 August 2020, under number 46/20. Results: Using data from 287 patients, the prediction showed R2 from 0.092 up to 0.972. The adjacent cranial and caudal EPA showed by far the most frequently significance in the prediction of all parameters used. Anthropometric and spino-pelvic parameters showed sparse impact, which was frequently in the lower lumbar regions. On average, a very good prediction was found. For two mEPA (L3/4 R2 = 0.914, L4/5 R2 = 0.953) and two bEPA (L3 R2 = 0.899, L4 R2 = 0.972), the R2 was >0.8. However, the predicted EPA differed for individual patients, even in these very effective prediction models—roughly around ±10° as compared to the measured EPA. Conclusions: In general, the prediction showed good to perfect results. In the supine position, the spinopelvic and anthropometric parameters show sparse impact on the prediction of mEPA or bEPA.

Alignment of the Sternum and Sacrum as a Marker of Sitting Body Posture in Children

An analysis of literature on the methods of assuming a sitting position and the results of our own research indicated the need to search for biomechanical parameters and existing relationships that would enable a description of sitting body posture. The purpose of this paper is to analyze the relationship between the alignment of the body of sternum and sacrum and the changes in the thoracic and lumbar spine curvatures in children. The study involved 113 subjects aged 9-13 years. A planned simultaneous measurement of the angle parameters of the alignment of the body of sternum and sacrum relative to the body's sagittal axis and the angle parameters of the thoracic and lumbar spine curvatures was performed during a single examination session. The proposed markers of alignment in the corrected sitting body posture are characterized by homogeneous results. A high measurement repeatability was observed when determining the corrected body posture in the study setting. It was noted that changes in the alignment of the body of sternum and sacrum resulted in changes in the thoracic kyphosis and lumbar lordosis angle values, which may be an important component of clinical observations of sitting body posture in children. Implementing the body of sternum alignment angle of about 64° relative to the body's sagittal axis in clinical practice as one of the objectives of postural education may be the target solution for sitting body posture correction in children.

Preoperative Association Between Quantitative Lumbar Muscle Parameters and Spinal Sagittal Alignment in Lumbar Fusion Patients

STUDY DESIGN

A retrospective cross-sectional study.

OBJECTIVE

To assess the association between spinal muscle morphology and spinopelvic parameters in lumbar fusion patients, with a special emphasis on lumbar lordosis (LL).

SUMMARY OF BACKGROUND DATA

Maintenance of sagittal alignment relies on muscle forces, but the basic association between spinal muscles and spinopelvic parameters is poorly understood.

MATERIALS AND METHODS

Patients operated between 2014 and 2017 who had both lumbar magnetic resonance imaging scan and standing whole-spine radiographs within six months before surgery were included. Muscle measurements were conducted on axial T2-weighted magnetic resonance images at the superior endplate L3-L5 for the psoas and L3-S1 for combined multifidus and erector spinae (paraspinal) muscles. A pixel intensity threshold method was used to calculate the total cross-sectional area (TCSA) and the functional cross-sectional area (FCSA). Spinopelvic parameters were measured on lateral standing whole-spine radiographs and included LL, pelvic incidence (PI), PI-LL mismatch, pelvic tilt, sacral slope, thoracic kyphosis, and sagittal vertical axis. Analyses were stratified by biological sex. Multivariable linear regression analyses with adjustments for age and body mass index (BMI) were performed.

RESULTS

A total of 104 patients (62.5% female) were included in the analysis. The patient population was 90.4% White with a median age at surgery of 69 years and a median BMI of 27.8 kg/m 2 . All muscle measurements were significantly smaller in women. PI, pelvic tilt, and thoracic kyphosis were significantly greater in women. PI-LL mismatch was 6.1° (10.6°) in men and 10.2° (13.5°) in women ( P =0.106), and sagittal vertical axis was 45.3 (40.8) mm in men and 35.7 (40.8) mm in women ( P =0.251). After adjusting for age and BMI, paraspinal TCSA at L3-L5, and paraspinal FCSA at L4 showed significant positive associations with LL in women. In men, psoas TCSA at L5 and psoas FCSA at L5 showed significant negative associations with LL, but none of the paraspinal muscle measurements.

CONCLUSION

Our findings indicate that psoas and lumbar spine extensor muscles interact differently on LL among men and women, creating a unique mechanical environment.

LEVEL OF EVIDENCE

Level 4.

Spinal stability analysis of lumbar interbody fusion according to pelvic type and cage angle based on simplified spinal model with various pelvic indices

Recently, the objectives of lumbar interbody fusion (LIF) have been extended to include the correction of broader/relative indications in addition to spinal fixation. Accordingly, LIF must be optimized for sagittal alignment while simultaneously achieving decompression. Therefore, a representative model classified into three pelvic types, i.e., neutral pelvis (NP), anterior pelvis (AP), and retroverted pelvis (RP), was selected according to the pelvic index, and LIF was performed on each representative model to analyze Lumbar lordosis (LL) and the corresponding equivalent stress. The finite element (FE) model was based on a sagittal 2D X-ray image. The calculation efficiency and convergence were improved by simplifying the modeling of the vertebral body in general and its posterior portion in particular. Based on the position of the pelvis, according to the pelvic shape, images of patients were classified into three types: AP, RP, and NP. Subsequently, representative images were selected for each type. The fixation device used in the fusion model was a pedicle screw and a spinal rod of a general type. PEEK was used as the cage material, and the cage shape was varied by using three different cage angles: 0°, 4°, and 8°. Spinal mobility: The pelvic type with the highest range of motion (ROM) for the spine was the NP type; the AP type had the highest LL. Under a combination load, the NP type exhibited the highest lumbar flexibility (LF), which was 2.46° lower on average compared to the case where a pure moment was applied. Equivalent stress on the spinal fixation device: The equivalent stress acting on the vertebrae was lowest when cage 0 was used for the NP and AP type. For the RP type, the lowest equivalent stress on the vertebrae was observed when cage 4 was used. Finally, for the L5 upper endplate, the stress did not vary significantly for a given type of cage. In conclusion, there was no significant difference in ROM according to cage angle, and the highest ROM, LL and LF were shown in the pelvic shape of NP type. However, when comparing the results with other pelvic types, it was not possible to confirm that LF is completely dependent on LL and ROM.

MRI grading of spinal stenosis is not associated with the severity of low back pain in patients with lumbar spinal stenosis

Background

Although lumbar spinal stenosis (LSS) often coexists with other degenerative conditions, few studies have fully assessed possible contributing factors for low back pain (LBP) in patients with LSS. The purpose of this study was to identify factors associated with the severity of LBP in patients with LSS.

Methods

The patients with neurogenic claudication caused by LSS, which was confirmed by magnetic resonance imaging (MRI) were included in this cross-sectional study. Data included ratings of LBP, buttock and leg pain, and numbness on a numerical rating scale (NRS), 36-item Short-Form Survey (SF-36) scores, muscle mass measured by bioelectrical impedance analysis, and radiographic measurements including lumbopelvic alignment and slippage. The severity of LSS, endplate defects, Modic endplate changes, intervertebral disc degeneration, and facet joint osteoarthritis were evaluated on MRI. Spearman correlation and multivariate linear regression analyses were used to examine the factors associated with the severity of LBP (NRS score).

Results

A total of 293 patients (135 male and 158 female, average age 72.6 years) were analyzed. LBP was moderately correlated with buttock and leg pain, and buttock and leg numbness. Significant but weak correlations were observed between LBP and body mass index, appendicular and trunk muscle mass, all domains of SF-36, pelvic tilt, total number of endplate defects and Modic endplate changes, and summary score of disc degeneration grading, but not severity or number of spinal stenoses. In the multivariate regression analysis, age, female sex, trunk muscle mass, diabetes, NRS buttock and leg pain, NRS buttock and leg numbness, SF-36 vitality, pelvic tilt, and total number of endplate defects were associated with the severity of LBP.

Conclusions

Trunk muscle mass, lumbopelvic alignment, and endplate defects, but not severity of stenosis are partly associated with severity of LBP, but buttock and leg pain and buttock and leg numbness have strongest relationships with LBP in patients with LSS.

Introduction of a Novel “Segmentation Line” to Analyze the Variations in Segmental Lordosis, Location of the Lumbar Apex, and Their Correlation with Spinopelvic Parameters in Asymptomatic Adults

Study Design

Cross-sectional study.

Purpose

This study aimed to understand the sagittal spinopelvic parameters, segmental lumbar parameters, and lumbar apex location in asymptomatic adults and analyze their correlations with each other.

Overview of Literature

Roussouly and his colleagues reported that pelvic incidence (PI) influences the lower arc of lumbar lordosis, whereas Pesenti and his colleagues reported that PI influences only the proximal part of lordosis and not the distal part. Both studies have their shortcomings.

Methods

One hundred asymptomatic adult volunteers (mean age, 29.1±7.9 years; 69 males, 31 females) who satisfied the selection criteria were enrolled in this study. Standing antero-posterior and lateral whole spine and pelvis X-rays were performed, and the radiographic parameters were analyzed. We introduced a “segmentation line” bisecting the apical vertebra/disk to divide the upper arc of lumbar lordosis (ULL) and lower arc of lumbar lordosis (LLL).

Results

The mean PI was 48.02°, ULL 29.12°, LLL 16.02°, total lumbar lordosis (TLL) 45.14°, lumbar tilt angle 4.73°, and location of the apex of lumbar lordosis (LLA) 4.11°. The location of the lumbar apex moved higher as the PI increased. The PI was strongly positively correlated with the LLL (r =0.582, p <0.001) and TLL (r =0.579, p <0.001) but not with the ULL (r =0.196, p =0.05). The LLA was strongly positively correlated with the ULL (r =0.349, p <0.001), negatively with the LLL (r =−0.63, p <0.001), and not correlated with the TLL (r =−0.177, p =0.078).

Conclusions

The PI influences the location of the lumbar apex, the LLL, and the TLL but not the ULL. The location of the lumbar apex significantly influences the segmental lordosis but not the TLL.

Association between acetabular dysplasia and sagittal spino-pelvic alignment in a population-based cohort in Japan

The relationship between acetabular dysplasia and spino-pelvic alignment remains unclear. The aim of this study was to clarify the association between acetabular dysplasia and spino-pelvic alignment, based on a large-scale population-based cohort in Japan. From the third survey of the Research on Osteoarthritis/Osteoporosis Against Disability (ROAD) study, 1,481 participants (491 men and 990 women; mean age, 65.3 years) were analyzed. Center-edge (CE) angle and spino-pelvic parameters (lumbar lordosis, LL; sacral slope, SS; pelvic tilt, PT; pelvic incidence, PI) were measured radiographically. Acetabular dysplasia was defined as a CE angle < 20°, and associations between acetabular dysplasia and spino-pelvic parameters were assessed. The group with acetabular dysplasia had significantly higher age, higher percentage of female, higher SS and higher PI than the group without acetabular dysplasia in a univariate analysis. On the other hand, acetabular dysplasia was not significantly associated with spino-pelvic parameters in a multiple logistic regression analysis that include age, sex, SS and PI as explanatory variables; however, PI demonstrated a positive odds ratio (odds ratio, 1.02; 95% CI 1.00–1.04). In conclusion, acetabular dysplasia was not significantly associated with spino-pelvic parameters, but higher PI may be an associated factor for acetabular dysplasia.

Effects of integrative neuromuscular training on the gait biomechanics of children with overweight and obesity

Objective

To analyze whether 13 weeks of integrative neuromuscular training can benefit spatiotemporal and kinematic parameters of gait in children with overweight/obesity.

Methods

This is a non‐randomized controlled trial. Fifty children (10.77 ± 1.24 years, 31 girls) with overweight/obesity were allocated to an exercise group (EG) (n = 25) that carried out a 13‐week exercise program based on fundamental movement skills, strength activities and aerobic training, and a control group (CG) (n = 25) that followed their normal lifestyle. Spatiotemporal (i.e., cadence, stance and support times, step length, and stride width) and kinematic (i.e., hip, pelvis, knee, and ankle angles) parameters were evaluated under laboratory conditions through a 3D analysis. ANCOVA was used to test raw and z‐score differences between the EG and CG at post‐exercise, adjusting for pre‐exercise values.

Results

The EG maintained their baseline stance and single‐limb support times while the CG increased them during walking (groups’ difference: 3.1 and 1.9 centiseconds). The EG maintained baseline maximum foot abduction angle during the stance phase whereas the CG showed an increase (groups’ difference: 3.9º). Additional analyses on kinematic profiles demonstrated that the EG walked with similar pelvic tilt and ankle abduction angles at post‐exercise, while the CG increased the pelvic anterior tilt in the whole stance phase (mean groups’ difference: 7.7º) and the ankle abduction angles in early‐ and mid‐stance phases (mean groups’ difference: 4.6º). No changes were observed in the rest of spatiotemporal and kinematic parameters.

Conclusions

The integrative neuromuscular training stopped the progression of some biomechanical alterations during walking in children with overweight/obesity. These findings could contribute to preventing common movement‐derived musculoskeletal disorders in this population, as well as preserving an optimal mechanical efficiency during walking.

Relationship between the Accuracy of the Acetabular Cup Angle and BMI in Posterolateral Total Hip Arthroplasty with CT-Based Navigation

Background and Objectives: Precise acetabular cup placement is essential for successful total hip arthroplasty (THA). In obese patients, its accuracy is often difficult to achieve because of the thickness of the soft tissues. This study aimed to determine the relationship between the accuracy of acetabular cup angle and body mass index (BMI) in posterolateral THA using the computed tomography-based navigation (CT-navi) system. Materials and Methods: We retrospectively reviewed 145 consecutive primary THAs using the CT-navi system between January 2015 and January 2018. All surgeries were performed using cementless cups employing the posterolateral approach with the patient in the decubitus position. We compared the radiographic inclination and anteversion obtained intraoperatively from the CT-navi with those measured by postoperative CT using three-dimensional templating software. We evaluated the relationship between the extent of errors and correlation with BMI. Results: In non-overweight patients (BMI < 25, 88 hips), the mean navigation errors for inclination were 2.8 ± 2.2° and for anteversion were 2.6 ± 2.3°. Meanwhile, in overweight patients (BMI ≥ 25, 57 hips), the mean navigation errors were 2.6 ± 2.4° for inclination and 2.4 ± 2.4° for anteversion. We found no significant difference between overweight and non-overweight patients in both inclination and anteversion. There was no correlation between the extent of errors and BMI. Conclusions: In posterolateral THA, CT-navi can aid the precise placement of the acetabular cup irrespective of a patient’s BMI.

Comparison of three validated systems to analyse spinal shape and motion

The assessment of spinal shape and mobility is of great importance for long-term therapy evaluation. As frequent radiation should be avoided, especially in children, non-invasive measurements have gained increasing importance. Their comparability between each other however stays elusive. Three non-invasive measurement tools have been compared to each other: Idiag M360, raster stereography and Epionics SPINE. 30 volunteers (15 females/15 males) have each been assessed by each system, investigating lumbar lordosis, thoracic kyphosis and spinal range-of-motion in the sagittal plane. Lumbar lordosis differed significantly (p < 0.001) between measurement devices but correlated significant to each other (Pearson’s r 0.5–0.6). Regarding thoracic kyphosis no significant difference and a high correlation (r = 0.8) could be shown between Idiag M360 and raster stereography. For lumbar mobility resulting measurements differed significantly and correlated only moderate between Idiag M360 and Epionics SPINE. Although the different measurement systems are moderate to high correlated to each other, their absolute agreement is limited. This might be explained by differences in their angle definition for lordotic and kyphotic angle, their measurement placement, or their capturing of mobility (static vs. dynamic assessment). Therefore, for long-term evaluation of the back profile, inter-modal comparison of values between different non-invasive devices should be avoided.

Decreased muscle mass and strength affected spinal sagittal malalignment

PURPOSE

Correction surgeries for spinal malalignment showed good clinical outcomes; however, there were concerns including increased invasiveness, complications, and impact on medico-economics. Ideally, an early intervention is needed. To better understand the patho-mechanism and natural course of spinal alignment, the effect of factors such as muscle mass and strength on spinal sagittal imbalance were determined in a multicenter cross-sectional study.

METHODS

After excluding metal implant recipients, 1823 of 2551 patients (mean age: 69.2 ± 13.8 years; men 768, women 1055) were enrolled. Age, sex, past medical history (Charlson comorbidity index), body mass index (BMI), grip strength (GS), and trunk muscle mass (TM) were reviewed. Spinal sagittal imbalance was determined by the SRS-Schwab classification. Multiple comparison analysis among four groups (Normal, Mild, Moderate, Severe) and multinomial logistic regression analysis were performed.

RESULTS

On multiple comparison analysis, with progressing spinal malalignment, age in both sexes tended to be higher; further, TM in women and GS in both sexes tended to be low. On multinomial logistic regression analysis, age and BMI were positively associated with spinal sagittal malalignment in Mild, Moderate, and Severe groups. TM in Moderate and Severe groups and GS in the Moderate group were negatively associated with spinal sagittal malalignment.

CONCLUSION

Aging, obesity, low TM, and low GS are potential risk factors for spinal sagittal malalignment. Especially, low TM and low GS are potentially associated with more progressed spinal sagittal malalignment. Thus, early intervention for muscles, such as exercise therapy, is needed, while the spinal sagittal alignment is normal or mildly affected.

Detection of cognitive decline by spinal posture assessment in health exams of the general older population

The recent increase in the older adult population has led to a higher prevalence of cognitive impairment, which is often overlooked in routine health examinations. Citizens aged 50-89 years were targeted for this cohort survey by random sampling from the resident registry of a cooperating town in 2014. A total of 411 participants (202 male and 209 female) were enrolled. We analyzed the distribution of cognitive function test scores as determined by Montreal Cognitive Assessment and Mini-Mental State Examination tests in each age (50's, 60's, 70's and 80's) and sex group to examine whether cognitive decline could be detected by sagittal spinal balance measurement based on a radiological approach. Sagittal spinal balance was quantitatively measured as sagittal vertical axis (SVA). We observed significant associations for higher age and/or SVA anteriorization with lower cognitive function. In males, spinal balance anteriorization was associated with cognitive decline independently of age, with combinations of age and SVA also making valid cognitive decline determinations; male cases of SVA ≥ 100 mm at any age, SVA ≥ 90 mm at ≥ 70 years, and SVA ≥ 70 mm at ≥ 80 years were all more likely to have cognitive decline than cases below those values. For females, cognitive decline was more likely in cases of SVA ≥ 70 mm, regardless of age. Thus, spinal balance anteriorization can be regarded as an easily visible indicator of latent cognitive decline in community-dwelling older people.

Relationship between the locomotive syndrome and kinetic and kinematic parameters during static standing and level walking

BACKGROUND

Individuals experiencing age-related decline in locomotor functions are at high-risk of developing locomotive syndrome (LS). LS requires long-term care and greatly influences the quality of life and activities of daily living. The LS risk test was established as a diagnostic criterion by the Japanese Orthopedic Association. Although the relationship between the test and motor function has been established, few studies have reported on the characteristics of LS kinematically and kinetically.

RESEARCH QUESTION

Do elderly with LS show different kinetic and kinematic characteristics compared with healthy elderly during static standing and level walking?

METHODS

Forty-four Participants were divided into an LS group and a non-LS group based on the scores of the LS risk test. The standing posture and walking of the participants were measured using a three-dimensional motion capture system. The results of the groups were compared using an unpaired t-test, and then the characteristics of the LS group were extracted using logistic regression analysis.

RESULTS

LS group exhibited trunk flexion during both standing and gait. A higher intervertebral disc compressive force, which is the index of the low-back mechanical stress, during standing and an increase in ankle plantarflexion angle during walking were observed in LS group.

SIGNIFICANCE

This study determined the kinematic and kinetic features of elderly with LS. The findings suggest that parameters related to the trunk and ankle could be associated with LS. Further studying the characteristics of LS in older adults via motion analysis can help develop prevention and intervention methods for LS.

Relationship Between Age-Related Spinopelvic Sagittal Alignment and Low Back Pain in Adults of Population-Based Cohorts: The ROAD Study

Purpose

The demand for surgical correction in elderly patients with adult spinal deformity (ASD) has recently increased with the growth of the aging population. Age-related changes in spinopelvic sagittal alignment have been recently reported; thus, sagittal realignment should consider age-related changes. This study aimed to investigate the relationship between age-specific sagittal spinopelvic radiographic parameters and low back pain (LBP) to support the establishment of age-specific realignment targets for patients with ASD.

Materials and Methods

A population-based cohort consisting of 1461 subjects (466 men and 995 women) was used. The participants were divided into five groups based on their age: (1) younger than 50 years, (2) 50–59 years, (3) 60–69 years, (4) 70–79 years, and (5) 80 years and older. Standing lateral whole-spine radiographs were assessed to measure lumbar lordosis (LL), pelvic tilt (PT), pelvic incidence (PI), and sagittal vertical axis (SVA). In addition, all participants were asked if they had LBP or not, using the following question: “Have you experienced LBP on most days during the past month and/or now?”.

Results

The crucial parameter associated with LBP was the mismatch between PI and LL (PI-LL). The mean values of all the radiographic parameters increased with age. PI-LL and PT reached 11.5° and 25.6°, respectively, for women without LBP in the super-aged group (age >80 years), which did not lie in the range of optimal values reported in the previous literature.

Conclusion

A new optimal age-related target may be needed for the management of patients with ASD.

Sagittal spine disposition and pelvic tilt during outdoor fitness equipment use and their associations with kinanthropometry proportions in middle-aged and older adults

BACKGROUND

Outdoor fitness training has become popular as a tool for improving the health, especially middle-aged and older adults. For this purpose, outdoor fitness equipment (OFE) have been installed in public areas. However, their safety and effectiveness are still unknown. The aim of the present research was to analyze the sagittal disposition of the spine and pelvic tilt during the use of OFE, and to determine the influence of anthropometric variables on these factors in middle-aged and older adults.

METHODS

Seventy healthy volunteers, 56 women and 14 men (age: 63.14 ± 8.19 years) participated in the study. Sagittal spine disposition and pelvic tilt were measured using a Spinal Mouse®, in the relaxed standing position, and during the use of the OFE. In addition, kinanthropometry variables were also measured according to the guidelines of the International Society for the Advancement of Kinanthropometry.

RESULTS

Regarding thoracic kyphosis, a significant decrease was found in thoracic kyphosis in the initial position (IP) in single bonny rider (SBR) (p = 0.006) and row (p = 0.046), and a significant increase in the final position (FP) in the row (p = 0.011), surfboard (p < 0.001) and air walker (p = 0.027) machines. In relation to the lumbar curvature and pelvic tilt, a significant decrease in lumbar lordosis and a decrease in pelvic anteversion were observed in the IP and FP in SBR and row; and in the bike (p < 0.001) machine. In the surfboard machine, a significant decrease in lumbar lordosis was found (p = 0.002), with no changes in pelvic tilt. According to the multiple linear regression analysis, the subjects with a higher cormic index and height were more at risk of increasing their thoracic kyphosis, decreasing lumbar lordosis and/or decreasing pelvic anteversion towards pelvic retroversion.

CONCLUSIONS

Middle-aged and older adults show spinal misalignments when using the OFE with respect to the standing position, showing a decrease in the thoracic kyphosis in IP of SBR and ROW, and a significant increase in the surfboard and air walker, and in the FP of Row, in the lumbar lordosis in all the OFE in sitting and some in standing, and in the pelvic anteversion in all the OFE in sitting. The variables height and the cormic index explained most of the changes in sagittal spine disposition.

Cervical Spinal Alignment Change Accompanying Spondylosis Exposes Harmonization Failure with Total Spinal Balance: A Japanese Cohort Survey Randomly Sampled from a Basic Resident Registry

The relationship between spinal posture and quality of life has garnered considerable attention with the increase in older community-dwelling residents. However, details of this association remain insufficient. A recent Japanese population cohort epidemiological locomotion survey (the Obuse study) revealed that the C2–C7 cervical sagittal vertical axis (CSVA) began to increase in males from their 60s, but not in females. This study aimed to clarify the pathology of these cervical spondylotic changes. A total of 411 participants (202 male and 209 female) aged between 50 and 89 years were selected by random sampling from a cooperating town’s resident registry. All participants underwent lateral X-ray photography in a standing position for the measurement of several sagittal spinal alignment parameters, including CSVA, C2–C7 cervical lordosis (CL), T1 slope (T1S), and sagittal vertical axis (SVA). The presence of cervical spondylotic changes was also recorded. Associations of cervical sagittal spinal alignment with cervical spondylosis and between cervical and total sagittal spinal alignment were examined. The prevalence of cervical spondylosis was significantly higher in males (81%) than in females (70%) (p = 0.01). CL was significantly smaller in cervical spondylosis subjects when adjusted by age (3.4 degrees less; p = 0.01). T1S minus CL displayed a moderate positive correlation with CSVA in both males and females (r = 0.49 and 0.48, respectively, both p < 0.01). In males only, CSVA and CL showed weak positive correlations with SVA (r = 0.31 and 0.22, respectively, both p < 0.01) independently of age. Cervical spinal misalignment was more clearly associated with diminished SF-8^TM scores in females than in males. In community-dwelling elderly residents, cervical sagittal spinal alignment change accompanying cervical spondylosis manifested as hypofunction to compensate for whole-spine imbalance.

Association of frailty with regional sagittal spinal alignment in the elderly

The degenerative changes in the spine of the frail elderly gradually exacerbate the alignment of the spine as the degeneration progresses. This study was conducted to assess the relationship between frailty and spine sagittal alignment measured in terms of global, cervical, thoracic, and lumbo-pelvic parameters. In total, 101 patients aged 75 years and older hospitalized for spine surgery were prospectively enrolled. We evaluated spinal sagittal parameters by dividing them into global (C7 sagittal vertical axis [SVA] and T1 pelvic angle [T1PA]), cervical (the C2-7 Cobb angle, Jackson line, and C2-7 plumb line), thoracic (thoracic kyphosis [TK]), and lumbo-pelvic (pelvic tilt [PT] and pelvic incidence minus lumbar lordosis value [PI-LL]). Patient characteristics; the Fatigue, Resistance, Ambulation, Illness, Loss of Weight (FRAIL) scale; and sagittal spinal parameters were included in the analysis. Multiple regression analysis was performed to identify associations between the FRAIL scale and sagittal spinal parameters. The FRAIL scale showed correlations with global sagittal parameters (C7 SVA [β = 0.225, p = 0.029] and T1PA [β = 0.273, p = 0.008]) and lumbo-pelvic parameters (PT [β = 0.294, p = 0.004] and PI-LL [β = 0.323, p = 0.001). Cervical and thoracic parameters were not directly associated with the FRAIL scale. LL and PI-LL were associated with TK, and TK was associated with cervical parameters (the C2-7 Cobb angle, Jackson line and C2-7 plumb line). In conclusion, frailty status could be an important factor that influences sagittal spinal alignment in the elderly. In this study, it was found that frailty mainly affected the balance of lumbo-pelvic alignment, and consequently affected the balance of the whole spine.

Sagittal imbalance of the spine-pelvis-lower extremity axis associated with back-related disability

BACKGROUND

The impact of sagittal imbalance in patients has been reported in LBP and LBP-related disabilities due to spinopelvic imbalance. However, no reports investigating the spine-pelvis-lower extremity axis using lateral images have been reported thus far. This study introduced a novel parameter of the spine-pelvis-lower extremity axis and evaluated whether this parameter was related to symptoms.

METHODS

A total of 343 subjects were included in this cross-sectional study. Standing spine-pelvis and pelvis-lower extremity radiographs were obtained to assess the sagittal vertical axis (SVA), pelvic tilt (PT), pelvic incidence (PI), sacral slope (SS), lumbar lordosis, and thoracic kyphosis. The sacral-knee distance (SKD) (i.e., distance from the anterior femoral condyle to the vertical axis at the upper posterior edge of S1 body) was measured. Furthermore, the SVA/SKD ratio was calculated for global balance. Subjects were divided into leg compensated (LC; SVA/SKD ratio <0.8) and decompensated (LD; SVA/SKD ratio ≥0.8) groups. The SVA was divided into balanced spine (BS; SVA ≤40 mm) and imbalanced spine (IS; SVA >40 mm) groups. All individuals were classified into LC + BS, LC + IS, LD + BS, and LD + IS groups. The relationships among the four groups and low back pain (LBP), Oswestry Disability Index (ODI), and knee pain were examined.

RESULTS

SKD was significantly correlated with SVA, SS, PI, PT, and knee-femoral angle. ODI was significantly higher in the LC + IS group than in the LD + BS group (p < 0.05). Knee pain prevalence was significantly higher in the LC + IS and LC + BS groups than in the LD + IS group (p < 0.05).

CONCLUSION

SVA/SKD ratio is useful for evaluating global alignment. Our findings are significant because they highlight the importance of SKD with respect to knee pain, LBP, and LBP- related disabilities.

Acetabular Morphology and Spinopelvic Characteristics: What Predominantly Determines Functional Acetabular Version?

Background:

In addition to the relative size of the acetabular rim and how the pelvis is positioned in space, the plane in which the acetabular version is calculated also affects its measurement.

Purpose:

To determine the relative contribution of pelvic and acetabular characteristics on morphological version (measured relative to the anterior pelvic plane angle [APPA]) and functional version (measured relative to the horizontal table).

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

Included were 50 acetabular dysplasia patients and 109 asymptomatic controls. Using image analysis software, morphological parameters of the pelvis and acetabulum were determined from 2-dimensional computed topography: pelvic incidence, pelvic tilt angle, sacral slope, APPA, morphological and functional acetabular versions, and subtended angles (measure of acetabular rim prominence relative to the femoral head center) around the acetabular clockface in 30° increments. Correlation and multivariable regression analyses were performed with morphological and functional version as dependent variables and spinopelvic and acetabular parameters as independent variables.

Results:

Morphological version was moderately associated with differences between anterior and posterior subtended angles (R = 0.68 [P < .001] and R = 0.57 [P < .001] for differences at 165° and 15° and 135° and 45°, respectively). Functional version was moderately associated with pelvic tilt angle (R = 0.56; P <.001) and the difference in subtended angles between anterior and posterior rims (R = 0.61 [P < .001] and R = 0.50 [P < .001] for differences at 165° and 15° and 135° and 45°, respectively). Multivariate analysis revealed a good model for predicting morphological version (R² = 0.44; P < .01) and functional version (R² = 0.58; P < .01). Subtended angle difference between 165° and 15° (B = 0.36 [95% CI, 0.24-0.49]; P < .001) was most strongly related to morphological version, and pelvic tilt angle (B = 0.57 [95% CI, 0.46-0.68]; P < .001) was most strongly related to functional version.

Conclusion:

Functional acetabular version was influenced most strongly by pelvic tilt angle rather than the relative prominence of the acetabular rims. Before determining surgical management for version abnormalities, it would be prudent to assess pelvic mobility and characteristics in different functional positions. In patients with minimal pelvic tilt change dynamically, corrective osteotomy would be the treatment of choice to improve functional version.

Marked Increase in Spinal Deformity Surgery Throughout the United States

STUDY DESIGN

Retrospective cohort database study.

OBJECTIVE

The aim of this study was to investigate trends in utilization and demographics in Spinal Deformity Surgery.

SUMMARY OF BACKGROUND DATA

The aging population in the United States will likely result in increased incidence of adult degenerative scoliosis. With a national focus on resource utilization and value-based care, it is essential for surgeons, researchers, and health care policy makers to know utilization and demographic trends of spinal surgery with long fusion construct.

METHODS

The National Inpatient Sample (NIS) database was queried for patients who underwent fusion or refusion of nine or more vertebrae (ICD-9-CM 81.64) between 2004 and 2015 across 44 states. Demographic and economic data include annual number of surgeries, incidence, patient age, sex, region, insurance type, charge, routine discharge, length of stay, and data. The NIS database represents a 20% sample of discharges from US hospitals, excluding rehabilitation and long-term acute care hospitals, which is weighted to provide national estimates.

RESULT

In 2014, there were 14,615 fusions involving nine or more vertebrae across the United States. The number of fusions involving nine or more levels has increased 141% from 6072 in 2004. Long fusion constructs increased 460% from 2004 to 2014 among patients 65 to 84 years' old. The mean hospital cost associated with long fusion spine surgery was $69,546 per case in 2015. Between 2004 and 2014, the payer breakdown for individuals receiving spinal deformity surgery is as follows: 54.2% private insurance, 18% Medicare, and 21.2% Medicaid.

CONCLUSION

The massive increase (141%) in utilization of long construct spine fusion was primarily driven by 460% rise in incidence of the surgery among those aged 65 to 84. Although the cause is unknown, it is possible that this rise was, at least in part, driven by the implementation of the affordable care act, improved surgical safety, and better knowledge of spinopelvic parameters.Level of Evidence: 3.

Clinical, Radiographic, and Genetic Analyses in a Population-Based Cohort of Adult Spinal Deformity in the Older Population

OBJECTIVE

This study aimed to identify the sagittal parameters associated with health-related quality of life and genetic variations that increase the risk of adult spinal deformity (ASD) onset in the older population.

METHODS

We recruited 120 participants who had a sagittal vertical axis > 50 mm in a sagittal imbalance study. Sagittal radiographic parameters, cross-sectional area, and intramuscular fatty infiltration using the Goutallier classification in the paraspinal lumbar muscles were evaluated. Functional scales included the self-reported Oswestry Disability Index (ODI), 36-item Short Form Health Survey (SF-36), and visual analogue scales (VAS) for back and leg pain. We performed whole-exome sequencing and an exome-wide association study using the 100 control subjects and 63 individuals with severe phenotypes of sagittal imbalance.

RESULTS

Pelvic incidence minus lumbar lordosis (PI-LL) mismatch was negatively associated with the SF-36 and positively correlated with ODI and VAS for back and leg pain. PI-LL was related to the quality and size of the paraspinal muscles, especially the multifidus muscle. We identified common individual variants that reached exome-wide significance using single-variant analysis. The most significant single-nucleotide polymorphism was rs78773460, situated in an exon of the SVIL gene (odds ratio, 9.61; p = 1.15 × 10-9).

CONCLUSION

Older age, higher body mass index, and a more significant PI-LL mismatch were associated with unfavorable results on functional scales. We found a genetic variation in the SVIL gene, which has been associated with the integrity of the cytoskeleton and the development of skeletal muscles, in severe ASD phenotypes. Our results help to elucidate the pathogenesis of ASD.

Dose-response relationship between spino-pelvic alignment determined by sagittal modifiers and back pain-specific quality of life

PURPOSE

To determine whether abnormalities of the sagittal modifiers (SMs) of the Scoliosis Research Society (SRS)-Schwab classification truly reflect back pain (BP)-specific quality of life (QOL), it is necessary to examine their dose-response relationships and to determine clinically impactful thresholds for declines in BP-specific QOL. This study aimed to analyse the continuous dose-response relationship between each SM and BP-specific QOL.

METHODS

This cross-sectional study, using data from a Japanese population-based cohort study, included 519 community-dwelling residents aged ≥ 50 years who participated in the annual health examination. The participants completed the Roland-Morris Disability Questionnaire (RDQ) on BP-specific QOL. Spino-pelvic alignment based on SMs was assessed by whole-spine X-ray examinations. We fitted general linear models with or without nonlinear terms to estimate the dose-response relationship between each SM and BP-specific QOL.

RESULTS

Pelvic tilt, pelvic incidence minus lumbar lordosis (PI-LL), and sagittal vertical axis showed dose-response relationships with BP-specific QOL measured as the RDQ score. PI-LL was most likely to predict a minimally clinically important RDQ score when its value exceeded the 90th percentile. A nonlinear relationship between PI-LL and the BP-specific QOL score was found. RDQ increased when PI-LL exceeded 10°.

CONCLUSION

PI-LL might be the most sensitive of the three modifiers of the SRS-Schwab classification for determining BP-specific QOL. Moreover, BP-specific QOL worsens rapidly when the compensatory mechanism against malalignment exceeds a critical value. Therefore, we suggest that traditional classifications and surgical strategies should be re-examined regarding the dose-dependent abnormalities of the SMs to develop a more reliable classification strategy.

How Do Pelvic Parameters Correlate With Postoperative Outcomes When the Parameters Are Not Measured Preoperatively in Patients Undergoing Instrumented Lumbar Fusion?

Objective: A normal age-adjusted sagittal alignment is an important factor in achieving long-term functional results after lumbar spinal fusion. We aim to determine if the changes in spino-pelvic alignment (SPA) correlate with post-operative functional outcomes in patients who underwent instrumented lumbar spine surgery when the parameters were not measured before.

Method: A retrospective review of medical records from 2012 to 2016, and radiographs of the patients who underwent instrumented fusion of the lumbar spine. The X-rays of the available preoperative lumbar spine were reviewed for SPA and compared with the last follow-up postoperative images. The patients were contacted by telephone to complete the EuroQoL 5 Dimensions 5-level questionnaire and visual analog scale for evaluation of their functional outcomes during 2017. Correlation studies were performed using Pearson’s coefficient.

Results: Forty-six patients were included with a mean age of 53 years and a follow-up of 47 months. There was a significant improvement in the functional outcomes and pain in the whole group. All the patients showed improvement in their SPA, and those who underwent more than two levels of fusion showed a significant improvement (P<0.05). Lumbar lordosis and sacral slope had a significant correlation with postoperative clinical improvement (R=0.8).

Conclusion: The study showed that single or double fusion has significant improvement in pain and functional outcome with a significant change in SPA.

Diagnosis of vertebral column pathologies using concatenated resampling with machine learning algorithms

Medical diagnosis through the classification of biomedical attributes is one of the exponentially growing fields in bioinformatics. Although a large number of approaches have been presented in the past, wide use and superior performance of the machine learning (ML) methods in medical diagnosis necessitates significant consideration for automatic diagnostic methods. This study proposes a novel approach called concatenated resampling (CR) to increase the efficacy of traditional ML algorithms. The performance is analyzed leveraging four ML approaches like tree-based ensemble approaches, and linear machine learning approach for automatic diagnosis of inter-vertebral pathologies with increased. Besides, undersampling, over-sampling, and proposed CR techniques have been applied to unbalanced training dataset to analyze the impact of these techniques on the accuracy of each of the classification model. Extensive experiments have been conducted to make comparisons among different classification models using several metrics including accuracy, precision, recall, and F ₁ score. Comparative analysis has been performed on the experimental results to identify the best performing classifier along with the application of the re-sampling technique. The results show that the extra tree classifier achieves an accuracy of 0.99 in association with the proposed CR technique.

Age-related degenerative changes and sex-specific differences in osseous anatomy and intervertebral disc height of the thoracolumbar spine

The aim of this study was to determine age-related changes and sex-specific differences in sagittal alignment, range of motion (ROM), and intervertebral disc height of the thoracolumbar spine in healthy subjects. Lateral neutral and flexion-extension radiographs of the thoracolumbar spine of 627 asymptomatic subjects (307 males and 320 females; average age, 49.6 ± 16.5 years) were evaluated. We included at least 50 males and 50 females in each decade of life between the 20s and the 70s. Intervertebral disc height from T10/T11 to L5/S1, local lordotic alignment, and ROM from T10-T11 to L5-S1 were measured. T10-L2 kyphosis and T12-S1 lordosis as well as flexion, extension, and total ROM were measured. T10-L2 kyphosis did not markedly change with age in subjects of either sex but a sudden increase was noted in the 70s females. T12-S1 lordosis increased with age in both sexes, except the 70s. Flexion, extension, and total ROM at T10-L2 and T12-S1 decreased with age in most subjects. The levels from L3-L4 to L5-S1 were conspicuous as mobile segments. Intervertebral disc height gradually increased from T10/T11 to L4/L5; the shortest was at T10/T11 and the longest at L3/L4 or L4/L5 in all subjects. Age-related decreases in intervertebral disc height were most prominent at L4/L5 in middle-aged and elderly individuals of both sexes. Normative values of sagittal alignment, ROM, and intervertebral disc height at each segmental level were established in both sexes and all age groups in healthy subjects.

Assessment of sagittal spinopelvic parameters in a Taiwanese population with spondylolysis by the EOS imaging system: a retrospective radiological analysis

Background

The impact of sagittal spinopelvic alignment on spondylolysis is well established in Caucasian populations. However, prior studies suggest that people from different ethnological backgrounds showed divergence, and a few studies that focused on Asian populations reported conflicting results. The aim of this study is to use the EOS imaging system to evaluate the spinopelvic parameters of spondylolysis patients, and their relationship with spondylolisthesis, disc degeneration, and age in a Taiwanese population.

Methods

Radiographic sagittal spinopelvic parameters for 45 spondylolysis patients and 32 healthy people were evaluated, including pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), thoracic kyphosis (TK), and lumbar lordosis (LL). The spinopelvic parameters were compared between spondylolytic and control groups. These parameters were further compared between spondylolytic subjects with and without spondylolisthesis, with and without high-grade disc degeneration, and young (< 30 years old) and middle-aged.

Results

The PI and LL of the spondylolytic group (52.6°±12.0° and 41.3°±15.2°) were significantly higher than those of the healthy control group (47.16°±7.95° and 28.22°±10.65°). Further analysis of the spondylolytic patients revealed that those with high-grade disc degeneration were more prone to spondylolisthesis (92.3 %) compared to those without (50 %; p = 0.001). The middle-aged group had significantly higher rates of spondylolisthesis (80 %) and high-grade disc degeneration (52.4 %) compared with those for the young group (45 and 16.7 %, respectively; p = 0.017 and 0.047, respectively). No statistically significant difference in the sagittal spinopelvic parameters was found when spondylolytic patients were divided according to the occurrence of spondylolisthesis or high-grade disc degeneration.

Conclusions

In a Taiwanese population, PI and LL were significantly larger in spondylolytic patients. Disc degeneration and age were associated with the occurrence of spondylolisthesis. Ethnological differences should thus be taken into account when making clinical decisions regarding spondylolysis in a Taiwanese population.

Correlation between thoracolumbar disc degeneration and anatomical spinopelvic parameters in supine position on MRI

Objective

This study aims to investigate the correlation between spinopelvic parameters in supine position (pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL)), disc degeneration and herniation of the thoracolumbar spine, as well as cardiovascular risk factors and back pain in a southern German cohort from the general population.

Methods

This study is a cross-sectional, case–control study drawn from a prospective cohort of the “Cooperative Health Research in the Region of Augsburg/Kooperative Gesundheitsforschung in der Region Augsburg” study (KORA). In total, 374 participants (mean age 56.4 ± 9.2 years; 57.8% male) from the whole-body MRI cohort (FF4) were included. All participants underwent a standardized whole-body MRI on which disc degeneration of the thoracic and lumbar spine was evaluated using a sequence adapted Pfirrmann score. PI, PT, SS and LL were measured according to the description in the literature, using sagittal imaging. Furthermore, disc bulging and protrusion were assessed. Correlations were estimated by logistic regression models providing odds ratios.

Results

Mean PI was 54.0° ± 11.1°, PT 13.0° ± 5.8°, SS 40.2° ± 8.8° and LL 36.2° ± 9.6°. SS was greater in men (p<0.05) and lumbar lordosis in women (p<0.001). PT increased by 0.09° per age-year with rising age. Age was not associated with PI, SS and LL. Neither BMI, hypertension, cholesterol, lipid levels, nor physical activity were associated with PI, PT, SS or LL. Diabetes mellitus negatively correlated with SS (β = -4.19; 95%CI -7.31–1.06, p<0.01). Smaller spinopelvic parameters (PI, SS and LL) where significantly (p<0.05) correlated with an increased frequency of disc bulging, as well as a local clustering in the lumbar, but not the thoracic spine.

Conclusion

In conclusion, spinopelvic parameters, measured in supine position, are significantly correlated with disc bulging alone; there is no significant correlation between supine spinopelvic parameters and disc degeneration, back pain or cardiovascular risk factors.

Computed tomography study of the relationship between pelvic incidence and bony contribution to lumbar lordosis in children

There is little data regarding the relationship in children and how it may change with aging. The aim of this radiographic study was to define the relationship between pelvic incidence (PI) and segmental vertebral body lordosis through childhood. In 150 children, CT scans of the lumbar spine and pelvis were analyzed measuring PI, sacral table angle (STA), sacral kyphosis (SK), and segmental lordosis (SL) individually L1-L5. Children were grouped by age: (1) 0-60 months; (2) 61-120 months; (3) 121-185 months. Mean PI for the entire cohort was 40.4, mean SL for L1-0.6, L2 0.0, L3 1.8, L4, 4.7, and L5 11.4. There were 40 children in Group 1, 63 in Group 2 and 37 in Group 3. SL differed between age groups at all levels except at L2. L1 and L2 became more kyphotic with increasing age; L3, L4, and L5 became more lordotic with increasing age. The correlation between PI and SL at each level became stronger with increasing age. Similarly, the correlation between PI and STA and between PI and SK also became stronger with increasing age. As children mature, the relationship between PI and segmental lordosis at each level of the lumbar spine becomes stronger-the relationship between PI and lordosis trends toward that seen in the adult. Future work should aim to define when the adult PI-LL relationship is realized.

Effect of lumbar laminectomy on spinal sagittal alignment: a systematic review

PURPOSE

Positive spinal sagittal alignment is known to correlate with pain and disability. The association between lumbar spinal stenosis and spinal sagittal alignment is less known, as is the effect of lumbar decompressive surgery on the change in that alignment. The objective was to study the evidence on the effect of lumbar decompressive surgery on sagittal spinopelvic alignment.

METHODS

The Cochrane Controlled Trials Register (CENTRAL), Medline, Embase, Scopus and Web of Science databases were searched in October 2019, unrestricted by date of publication. The study selection was performed by two independent reviewers. The risk of systematic bias was assessed according to the NIH Quality Assessment Tool. The data were extracted using a pre-defined standardized form.

RESULTS

The search resulted in 807 records. Of these, 18 were considered relevant for the qualitative analysis and 15 for the meta-synthesis. The sample size varied from 21 to 89 and the average age was around 70 years. Decompression was mostly performed on one or two levels and the surgical techniques varied widely. The pooled effect sizes were most statistically significant but small. For lumbar lordosis, the effect size was 3.0 (95% CI 2.2 to 3.7) degrees. Respectively, for pelvic tilt and sagittal vertical axis, the effect sizes were - 1.6 (95% CI .2.6 to - 0.5) degrees and - 9.6 (95% CI - 16.0 to - 3.3) mm.

CONCLUSIONS

It appears that decompression may have a small, statistically significant but probably clinically insignificant effect on lumbar lordosis, sagittal vertical axis and pelvic tilt.

Radiologic prognostic factors of curve progression in early degenerative lumbar scoliosis

OBJECTIVE

Several radiological parameters related to the aging spine have been reported as progression factors of early degenerative lumbar scoliosis (DLS). However, it has not been determined which factors are the most important. In this study the authors aimed to determine the risk factors associated with curve progression in early DLS.

METHODS

Fifty-one patients with early DLS and Cobb angles of 5°-15° were investigated. In total, 7 men and 44 women (mean age 61.6 years) were observed for a mean period of 13.7 years. The subjects were divided into two groups according to Cobb angle progression (≥ 15° or < 15°) at the final follow-up, and radiological parameters were compared. The direction of scoliosis, apical vertebral level and rotational grade, lateral subluxation, disc space difference, osteophyte difference, upper and lower disc wedging angles, and relationship between the intercrest line and L5 vertebra were evaluated.

RESULTS

During the follow-up period, the mean curve progression increased from 8.8° ± 3.2° to 19.4° ± 8.9°. The Cobb angle had progressed by ≥ 15° in 17 patients (33.3%) at the final follow-up. In these patients the mean Cobb angle increased from 9.4° ± 3.4° to 28.8° ± 7.5°, and in the 34 remaining patients it increased from 8.5° ± 3.1° to 14.7° ± 4.8°. The baseline lateral subluxation, disc space difference, and upper and lower disc wedging angles significantly differed between the groups. In multivariate logistic regression analysis, only the upper and lower disc wedging angles were significantly correlated with curve progression (OR 1.55, p = 0.035, and OR 1.89, p = 0.004, respectively).

CONCLUSIONS

Asymmetrical degenerative change in the lower apical vertebral disc, which leads to upper and lower disc wedging angles, is the most substantial factor in predicting early DLS progression.

Prevalence and associated factors of pistol grip deformity in Japanese local residents

Pistol grip deformity (PGD) may be the main factor in femoroacetabular impingement development. This study aimed to clarify the epidemiological indices and factors related to PGD in Japanese people. This population-based cohort study included 1575 local Japanese residents. PGD, center edge angle, and joint space width were measured radiographically. We investigated the relationship between PGD and spino-pelvic parameters. Factors associated with PGD were examined using multiple logistic regression analysis, with the presence/absence of PGD as an objective variable, and sex, age, body mass index (BMI), and the presence/absence of hip pain or spino-pelvic parameters as explanatory variables. In the entire cohort, 4.9% (10.6% men, 2.1% women) had PGD on at least one side. A trend was observed between PGD and increasing age in both men and women (men: p < 0.0001, women: p = 0.0004). No relationship was observed between PGD and hip pain (risk ratio 1.0 [95% confidence interval 0.97–1.03]). Factors significantly associated with PGD were age, sex, and BMI in the multivariate model. Acquired factors may be related to PGD in Japanese people as the PGD prevalence increased with age and PGD was not significantly associated with hip pain. This study provides new insights into the etiology and clinical significance of PGD.