Sagittal standing posture, back pain, and quality of life among adults from the general population: a sex-specific association

The standard posture is a myth: a scoping review

BACKGROUND

The standard posture described in Kendall's manual is commonly used for postural assessment. However, no bibliographic reference was provided to support its use.

OBJECTIVE

To identify the original source and the procedure followed for the design of that posture and to compare it with current literature on the subject.

METHODS

In accordance with the PRISMA Extension for Scoping Reviews recommendations, PubMed and Scopus were searched using the terms "standing posture", "plum line," and "gravity line". Publications in English, French, German, or Spanish that referred to posture in adults without pathology were included.

RESULTS

Six articles and 3 books were included in the final analysis. An identical posture to that described in Kendall's manual was identified in an early 19th-century work carried out with the unrealistic objective of maintaining static bipedal standing without muscular support, and including several anatomical misconceptions. Furthermore, the "ideal alignment" described in Kendall's manual does not correspond to the actual line of gravity, the comfortable posture, or natural postural compensations due to age, gender, or race.

CONCLUSION

The utilization of this standard to ascertain postural deficiencies is not supported by current evidence and may result in numerous false positives, particularly in the elderly.

Comparison between rasterstereographic scan and orthopedic examination for posture assessment: an observational study

Background

Although the relationship between posture and back pain is still under debate, the potential role of body alignment highlights the importance of postural assessment in the health sector. Despite growing concern about musculoskeletal issues, there remains a lack of consensus on effective methods for detecting postural anomalies.

Methods

This observational study compared postural assessments conducted by orthopedic specialists with those obtained through rasterstereographical spine scans using the DIERS formetric system. Fifty-four children from the third grade (mean age 9.4 years) underwent both assessments, allowing for a comprehensive examination of orthopedic abnormalities. Statistical analysis, including McNemar tests, was employed to compare the results of the assessments and evaluate potential discrepancies.

Results

The comparison between the orthopedic examination and the DIERS scan revealed significant differences in assessing trunk imbalance (p < 0.001), thoracic kyphosis (p < 0.001), and lumbar lordosis (p < 0.001). Additionally, the study identified a high prevalence of orthopedic abnormalities, with 79.6% of the examined children exhibiting at least one issue in the orthopedic visual assessment.

Conclusions

The study highlights the divergence between orthopedic evaluations and DIERS scans, emphasizing the challenges in achieving consistent postural assessments. The static analysis provided by the DIERS system, which quantifies posture in angles and distances, contrasts with the dynamic, functionality-focused approach of orthopedic examinations. The findings raise questions about the practicality and significance of integrating rasterstereography into routine pediatric orthopedic practice. The results underscore the complexity of postural evaluations and advocate for a comprehensive approach to address the multifaceted nature of back health in children.

Characterization of Lumbar Lordosis: Influence of Age, Sex, Vertebral Body Wedging, and L4-S1

STUDY DESIGN

Retrospective radiographic review.

OBJECTIVE

The objectives of the study were to determine the contributions to lumbar lordosis (LL) through both the vertebrae and the intervertebral disc (IVD), and to investigate the relationships between lumbar sagittal spine measurements and age and gender.

SUMMARY OF BACKGROUND DATA

A small body of literature exists on the relative contributions of vertebral body and IVD morphology to LL, the effects of L4-S1 on overall LL, and the relationships/correlations between lumbar sagittal spine measurements.

METHODS

Patients who met the inclusion criteria were retrospectively evaluated. Measurements included LL, pelvic incidence (PI), and % contributions of vertebral body wedging/IVD wedging/L4-S1 to LL. Patients were separated into groups by age and sex, demographic data were collected, and statistical analysis was completed.

RESULTS

LL decreased with age, although PI remained similar. Females demonstrated increased LL and vertebral body wedging % than males. Males demonstrated increased L4-S1% than females. Despite a decrease in LL with age, patients maintained L4-S1% and IVD wedging %. There was a significant negative relationship between PI and IVD wedging, PI and L4-S1%, and LL and L4-S1%.

CONCLUSIONS

During aging, the lumbar spine loses LL linearly. This occurs in the IVD and vertebral bodies. Females have increased LL compared with males, because of an increase in vertebral body wedging and IVD/vertebral wedging cranial to L4. In patients with high PI or LL, increased LL occurs from cranial to L4 and from vertebral body wedging.

Breast Hypertrophy: A Real Pain in the Back

BACKGROUND

Bilateral breast hypertrophy comes with signs and symptoms ranging from mild to debilitating. Bilateral breast reduction (BBR) is one of the most frequently performed plastic surgery procedures, and its effects on parameters such as spinal balance, paraspinal muscle function, and physical performance have not been thoroughly evaluated. The objective of this study was to evaluate the effects of BBR using advanced spine imaging modalities, and pain resolution.

METHODS

A prospective, observational, cohort study was carried out at the McGill University Health Centre. The following measures were recorded preoperatively and postoperatively for each patient: patient questionnaires (BREAST-Q and Pain), magnetic resonance imaging, and EOS low-radiation spinal scan.

RESULTS

Significant postoperative pain reduction was recorded, and there was up to 148% improvement in physical tests. Improvement in all questionnaire and BREAST-Q categories was documented. Preoperative and postoperative magnetic resonance imaging did demonstrate a statistically significant absence of permanent anatomical skeletal sequelae. Postoperative improvement in thoracic kyphosis was documented.

CONCLUSIONS

Quality-of-life scores are uniformly improved following BBR. Key findings following BBR include significant pain reduction and no evidence of spinal skeletal change. This is a finding of major importance in view of the practice of many insurance companies/third-party payer and health care systems that use the Schnur scale. The Schnur scale associates a weight for resection with body size that is not directly predictive of pain relief. This may indicate the need for more precise or different guidelines based on these quantitative findings.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

The dynamic postural steadiness and stabilization time between older adults with and without recurrent low back pain

BACKGROUND

Although postural control measures were reported to identify neuromuscular impairments, postural steadiness and stabilization time were not carefully investigated between subjects with and without recurrent low back pain (LBP). Research QuestionAre there group differences in the stabilization time, direction of sway, and dynamic postural steadiness index (DPSI) during one-leg standing?

METHODS

Thirty-four control subjects and 29 subjects with recurrent LBP participated in the study. Each subject stood upright on a single leg with and without visual input. The outcomes were measured for standing duration (sec), direction of sway, and the DPSI, which included the vertical steadiness index (VSI). The VSI assesses fluctuations to standardize the vertical ground reaction forces on the force plate.

RESULTS

The control group demonstrated significantly longer standing duration compared to the LBP group during the eyes-open condition (t = 3.55, p = 0.001). The LBP group demonstrated significantly faster stabilization time (t = 2.53, p = 0.01) in the sagittal plane. The DPSI demonstrated an excellent relationship with the VSI without visual input in the control group (r = 0.98, p = 0.001). The directions of sway demonstrated a significant interaction between groups (F = 9.29, p = 0.004).

SIGNIFICANCE

Although standing duration in the eyes-open condition decreased in the LBP group, a faster stabilization time in the sagittal plane was evident compared to the control group to adapt postural stability. These results indicated that vertical dynamic steadiness with visual input might be important to enhance compensatory postural control.

The Impact of Spinopelvic Parameters on Hip Degeneration After Spinal Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

This study aimed to investigate the effects of spinopelvic alignment parameters after spinal fusion on the rate of joint space narrowing in nonarthritic hips.

SUMMARY OF BACKGROUND DATA

Spinal fusion affects the forces on the adjacent hip joint. Therefore, hip joint narrowing may be increased after spinal fusion surgery. However, the relationship between spinal alignment and hip degeneration remains unclarified.

METHODS

We retrospectively reviewed data from patients who underwent lumbar spinal fusion from 2011 to 2018 at our institute. Patients with hip osteoarthritis (Kellgren-Lawrence grade ≥II) or hip dysplasia were excluded. The rate of hip joint space narrowing after spinal fusion was measured in 191 patients (382 hips). We assessed the effects of the following spinopelvic alignment parameters on the joint narrowing rate: pelvic tilt, sacral slope (SS), pelvic incidence (PI), lumbar lordosis (LL), PI-LL, sagittal vertical axis, and distance between the C7 plumb line, and the central sacral vertical line (C7-CSVL).

RESULTS

The hip joint narrowing rate was greater when four or more levels were fused compared with single-level fusion. After adjusting for the effects of patient-related factors, the alignment parameters significantly associated with the hip joint narrowing rate were the PI ( P = 0.0002), SS ( P = 0.047), and PI-LL ( P = 0.0022). A subgroup analysis of patients who underwent long fusion (four or more levels combined with iliac screws) also indicated that the PI ( P = 0.013), SS ( P = 0.0054), and PI-LL ( P = 0.046) were associated with the hip joint narrowing rate.

CONCLUSION

The PI, SS, and PI-LL were associated with the progression of hip joint narrowing after spinal fusion, especially after fusion of four or more levels. Surgeons need to be aware of the risk of increased hip joint narrowing in patients with a large PI, SS, and PI-LL after fusion surgery.

The Impact of Childhood Obesity on Joint Alignment: A Systematic Review and Meta-Analysis

OBJECTIVE

It has been suggested that overweight/obesity (OW/OB) impairs the normal alignment of children and adolescents' musculoskeletal system. However, to date, no study has systematically reviewed or quantified the effect of OW/OB on the development of joint malalignments in children and adolescents. The purpose of this study was to systematically review the association between OW/OB and joint alignment in children and adolescents and to quantify the evidence on whether children and adolescents with OW/OB have a higher risk of developing joint malalignments than their peers of normal weight.

METHODS

PubMed and Web of Science databases were systematically searched from inception to March 9, 2020. Studies investigating the association between OW/OB and joint alignment in children and adolescents were selected. Nonoriginal articles, participants with movement pattern diseases, and adolescents studied while pregnant were excluded. Two independent reviewers conducted the study selection and data extraction. Qualitative synthesis of evidence and random effect meta-analyses (risk ratio [RR]) were performed.

RESULTS

Seventy-three studies (5 longitudinal and 68 cross-sectional) met the inclusion criteria involving 1,757,107 children and adolescents. There was consistent evidence supporting associations of OW/OB with rounded shoulder, lumbar hyperlordosis, genu valgum, and flatfoot. Our meta-analysis showed that children and adolescents with OW/OB had a significantly higher risk of lumbar hyperlordosis (RR = 1.41), genu valgum (RR = 5.92), flatfoot (RR = 1.49), and any joint malalignment (RR = 1.68) when compared with their peers of normal weight. The presence of genu valgum and flatfoot were the most robust results.

CONCLUSION

Based on these findings, OW/OB is associated with the presence of joint malalignments in children and adolescents.

IMPACT

This is the first study that has systematically reviewed the effect of OW/OB on the development of joint malalignments in children and adolescents.

Characteristics of the spinopelvic parameters of patients with sacroiliac joint pain

To evaluate the characteristics of the spinopelvic parameters on radiography in patients with sacroiliac joint pain (SIJP). Two hundred fifty patients were included and divided into the SIJP group (those diagnosed with SIJP based on physical findings and response to analgesic periarticular injections; n = 53) and the non-SIJP group (those with low back pain [LBP] because of other reasons; n = 197). We compared their demographic characteristics and spinopelvic parameters using radiography. All differences found in the patients' demographic characteristics and spinopelvic parameters were analyzed. More female participants experienced SIJP than male participants (P = 0.0179). Univariate analyses revealed significant differences in pelvic incidence (PI) (P = 0.0122), sacral slope (SS) (P = 0.0034), and lumbar lordosis (LL) (P = 0.0078) between the groups. The detection powers for PI, SS, and LL were 0.71, 0.84, and 0.66, respectively. Logistic regression analyses, after adjustment for age and sex, revealed significant differences in PI (P = 0.0308) and SS (P = 0.0153) between the groups, with odds ratios of 1.03 and 1.05, respectively. More female participants experienced SIJP than male participants. Higher PI and SS values were related to SIJP among LBP patients.

General method for automated feature extraction and selection and its application for gender classification and biomechanical knowledge discovery of sex differences in spinal posture during stance and gait

Modern technologies enable to capture multiple biomechanical parameters often resulting in relational data. The current work proposes a generally applicable method comprising automated feature extraction, ensemble feature selection and classification to best capture the potentials of the data also for generating new biomechanical knowledge. Its benefits are demonstrated in the concrete biomechanically and medically relevant use case of gender classification based on spinal data for stance and gait. Very good results for accuracy were obtained using gait data. Dynamic movements of the lumbar spine in sagittal and frontal plane and of the pelvis in frontal plane best map gender differences.

Lumbar Muscle Fat Content Has More Correlations with Living Quality than Sagittal Vertical Axis in Elderly Patients with Degenerative Lumbar Disorders

Purpose

As the most poorly tolerated and debilitating form of spinal malalignment, sagittal imbalance is becoming an increasingly recognized cause of pain and disability in adults. However, there is evidence showing that sagittal imbalance has a weak or no correlation with health-related quality-of-life (HRQoL) outcomes. The objective of this study was to describe the direct factor associated with HRQoL in terms of Oswestry Disability Index (ODI) assessment.

Patients and Methods

This study retrospectively evaluated the clinical and radiographic information of 179 elderly patients with degenerative lumbar disorders and suboptimal sagittal standing posture (sagittal vertical axis>50 mm). Patient-reported outcomes were assessed using ODI. Patients with ODI≥40% were assigned to Group D (disability), while those with ODI<40% were assigned to Group ND (non-disability).

Results

Compared with Group ND (n=104), patients in Group D (n=75) had greater thoracolumbar kyphosis, pelvic incidence-lumbar lordosis (PI-LL), sagittal vertical axis (SVA), T1 pelvic angle, and fat infiltration, and smaller LL and muscle mass ratio. Pearson analysis revealed a high correlation between the percentage of fat infiltrated and ODI (r=768, P<0.01) and moderate correlation between SVA and ODI (r=0.408, P<0.001). Linear regression results indicated that fat infiltration was an independent factor associated with ODI. ODI significantly correlated with SVA in patients with major fat infiltration (r=0.328, P=0.001), while having no correlation with SVA in those with moderate or minor fat infiltration (r=0.083, P=0.464).

Conclusion

Lumbar muscle fat infiltration is an independent factor associated with the living quality in terms of ODI assessment in the elderly population with degenerative lumbar disorders, which has more correlations with ODI scores than the sagittal imbalance. The relationship between HRQoL outcomes and sagittal imbalance depends on the quality of lumbar muscle.

Investigating the Correlation Between Anterior-Posterior and Lateral Asymmetric Muscular Balance With Low Back Pain

Objective

The objective of this pilot study was to determine if there is a correlation between the proposed physical testing protocol and low back pain. The proposed physical testing protocol is an attempt to assess muscular asymmetry in the anterior-posterior plane and the lateral plane.

Methods

A total of 96 volunteers were recruited from Touro University after obtaining IRB approval. Volunteers were initially provided a questionnaire regarding demographics and back pain. After ensuring participants satisfied the inclusion criteria, a physical test protocol was performed. After data compilation, odds ratios as well and linear regression models were generated to assess for correlation with back pain.

Results

A total of 96 participants were recruited. The odds ratio for asymmetric anterior-posterior balance in relation to back pain is 3.00 with a 95% confidence interval 1.26-7.12. The odds ratio for total ability to tolerate asymmetric loads greater than 50% of ideal body weight is 0.44 with a 95% confidence interval 0.11-1.77. The linear regression coefficient of anterior-posterior balance greater than 25% of ideal body weight in relation to level of pain is 1.96.

Conclusions

Increased muscular asymmetry in the sagittal plane and lateral plane showed a trend toward increased levels of low back pain; however, there is a weak correlation. This is a correlation and not an association. Future studies to assess the relationship between muscular balance and low back pain are needed to determine if therapy can be targeted to improve muscular sagittal balance, which can improve symmetry and back pain.

Correlations between radiographic spinopelvic parameters and health-related quality of life: A prospective evaluation of 37 patients with facioscapulohumeral muscular dystrophy

OBJECTIVE

The purpose of this study was to evaluate the relationship between spinopelvic parameters and health-related quality of life.

METHODS

Patients with Facioscapulohumeral muscular dystrophy (FSHD) were asked to volunteer to participate in this study from April 2018 to December 2019. Patient data, including age, sex, body mass index (BMI), and duration of the diagnosis of FSHD were obtained. Short Form (SF-36) questionnaire was completed for all patients. All patients underwent lateral radiography of the whole spine. The radiographic parameters examined were pelvic tilt (PT), pelvic incidence (PI), sacral slope (SS), lumbar lordosis (LL), cervical lordosis (CL), T1 spinopelvic inclination (T1 SPI), thoracic kyphosis (TK), Pelvic incidence- lumbar lordosis (PI-LL) and sagittal vertical axis (SVA).

RESULTS

Thirty-seven patients (16 females and 21 males) were included in the study, with a mean age of 39.1 years. The mean duration of diagnosis was 13.5 ± 11.4 years and mean BMI was 24.2 kg/m2. Physical composite score (PCS) was 38.7 and mental composite score (MCS) 60.8 detected. Radiographic analyses included the following: the mean PT was 9.1°, PI 52.1°, SS 43.5°, LL 67.9°, CL 9.8°, T1 SPI -2.5°, TK 23.1°, SVA 37.6 mm. PI-LL was -13.1°. We identified 31 patients with match (left) PI-LL and six patients with mismatch (right) PI-LL.

CONCLUSION

Hyperlordosis inlumbar spine, hypolordosis in cervical spine and negative sagittal balance were the most common spinal misalignments in patients with FSHD. These patients have lower composite PCS than composite MCS. There was a significantly negative correlation between LL, PI-LL and PCS.

LEVEL OF EVIDENCE

Level IV Cross-sectional study.

Classification System of the Sagittal Integral Morphotype in Children from the ISQUIOS Programme (Spain)

The sagittal spinal morphology presents 4 physiological curvatures that increase endurance to axial compression forces and allow adequate postural balance. These curves must remain within normal ranges to achieve a static and dynamic balance, a correct functioning of the muscles and an adequate distribution of the loads, and thus minimize the injury risk. The purpose of this study was to categorize the sagittal spinal alignment according to the different morphotypes obtained for each curve in standing, slump sitting, and trunk forward bending positions in schoolchildren. It was a cross-sectional study. Sagittal spinal curvatures were assessed in 731 students from 16 elementary schools. In the sagittal standing position assessment, 70.45% and 89.06% of schoolchildren presented a “normal” morphotype for both dorsal and lumbar curves, respectively. After the application of the “Sagittal Integral Morphotype” protocol according to the morphotypes obtained in the three positions assessment (standing, slump sitting, and trunk forward bending), it was observed how the frequency of normal morphotypes for the dorsal and lumbar curve decreased considerably (only 32% and 6.6% of children obtained a “normal sagittal integral morphotype” for the thoracic and lumbar curvatures, respectively). These results show how it is necessary to include the slump sitting and trunk forward bending assessment as part of the protocol to define the “integral” sagittal alignment of the spine and establish a correct diagnosis. The use of the diagnostic classification presented in this study will allow early detection of misalignment not identified with the assessment of standing position.

Spinal shrinkage, sagittal alignment and back discomfort changes in manufacturing company workers during a working day

Prolonged standing and lifting heavy loads are risk factors for the appearance of low back pain in work. The aim of this study was to observe changes in the height, spinal sagittal alignment, and the lumbar and dorsal discomfort perception in assembly line workers. Cross-sectional study, 40 assembly line workers (6 females). Height, sitting height, grades of thoracic kyphosis and lumbar lordosis and perceived spine discomfort, before and after the working day, were determined. Thoracic and lumbar sagittal alignment was compared between discomfort developers and no developers. There was a significant decrease in the height and sitting height of the workers at the end of the day. Thoracic and lumbar curvature increased significantly, as did the perceived lumbar discomfort. Workers on the assembly line, in a prolonged standing work, suffer an increase in lumbar discomfort, and changes in height and thoracic and lumbar curvatures. Practitioner summary: Spinal shrinkage, sagittal alignment and back discomfort (upper and lower back), were analysed in assembly line workers in prolonged standing during a workday. Assembly line workers suffer a decrease in height, an increase in their thoracic and lumbar curvature, and in lumbar discomfort throughout their workday.

Repeat Radiography in Monitoring Structural Changes in the Treatment of Spinal Disorders in Chiropractic and Manual Medicine Practice: Evidence and Safety

There is substantial evidence for normal relationships between spine and postural parameters, as measured from radiographs of standing patients. Sagittal balance, cervical lordosis, thoracic kyphosis, lumbar lordosis, pelvic tilt, and the more complex understanding of the interrelations between these essential components of normal stance have evolved to where there are known, established thresholds for normalcy. These spinal parameters are reliably measured from X-ray images and serve as goals of care in the treatment of spine and postural disorders. Initial and follow-up spinal imaging by X-ray is thus crucial for the practice of contemporary and evidence-based structural rehabilitation. Recent studies have demonstrated that improvement in the spine and posture by nonsurgical methods offers superior long-term patient outcomes versus conventional methods that only temporarily treat pain/dysfunction. Low-dose radiation from repeated X-ray imaging in treating subluxated patients is substantially below the known threshold for harm and is within background radiation exposures. Since alternative imaging methods are not clinically practical at this time, plain radiography remains the standard for spinal imaging. It is safe when used in a repeated fashion for quantifying pre-post spine and postural subluxation and deformity patterns in the practice of structural correction methods by chiropractic and other manual medicine practices.

NATURAL HISTORY OF LUMBAR CANAL STENOSIS: CLINICAL ASPECTS AND SAGITTAL BALANCE

ABSTRACT Objective To compare the sagittal alignment (SA) parameters in individuals with LCS and surgical indication with a control group and to study the correlations between SA parameters and ODI, VAS and EQ-5D in individuals with LCS and surgical indication. Methods In this multicenter cross-sectional case-control study, the individuals were allocated as follows. A stenosis group (SG) composed by patients with LCS confirmed by magnetic resonance imaging with surgical indication, treated between July 2010 and August 2016 and a control group (CG), without LCS. All subjects underwent anamnesis, completed the Health-related Quality of Life (HRQoL) and total spine radiographs were taken. Clinical data, HRQoL and radiographic parameters were correlated. Results Sixty-four individuals formed the SG and 14 the CG. The SG had higher values of mean age, coronal imbalance, sagittal vertical axis (SVA), pelvic tilt (PT), sacrofemoral distance (SFD), overhang (OH), PI-LL mismatch, Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) for pain and smaller thoracic kyphosis (TK), total (TLPL) and regional lumbopelvic lordosis (RLPL) in all vertebrae, sagittal offset (SO) in all evaluated vertebrae and EuroQol-5D (EQ-5D) with p <0.05. In the SG, the only significant correlations (p <0.05) were between TK and ODI and EQ-5D; all the other sagittal parameters did not correlated with VAS, ODI or EQ-5D. Conclusion SG had SA parameters altered in relation to CG. There was a direct correlation between decrease in TK and worsening of ODI and EQ-5D in SG. Level of evidence: III; Case Control Study.

The association between sacroiliac joint-related pain following lumbar spine surgery and spinopelvic parameters: a prospective multicenter study

PURPOSE

To prospectively calculate the incidence of postoperative sacroiliac joint-related pain (SIJP) and investigate the association between spinopelvic parameters and postoperative SIJP after lumbar spine surgery.

METHODS

We prospectively enrolled consecutive patients who underwent lumbar spine surgery. We defined postoperative SIJP as unilateral buttock pain according to fulfillment of the following criteria within 3 months of the surgery: a sacroiliac joint (SIJ) score higher than 4/9 postoperatively; positive response to analgesic periarticular SIJ injection with fluoroscopy; no other complications related to the surgery. The patients were divided into the SIJP group and non-SIJP group. We compared the background information and analyzed the differences in spinopelvic parameters in both groups. Additionally, receiver-operating characteristic curve analyses were performed to evaluate the cutoff values of spinopelvic parameters.

RESULTS

Of the 281 patients enrolled, 265 were included and eight developed postoperative SIJP (3.0%). There were no significant differences in the background information between groups. Preoperative and postoperative radiological evaluations revealed that the pelvic incidence (PI) in the SIJP group was significantly higher than that in the non-SIJP group, and there were no significant differences in lumbar lordosis (LL), pelvic tilt, sacral slope, and PI minus LL. For preoperative PI, the area under the curve, cutoff value, sensitivity, and specificity were 0.73739, 59, 62.5%, and 81.9%, respectively.

CONCLUSIONS

The incidence of postoperative SIJP after lumbar spine surgery was 3.0%. Higher PI values were associated with a higher risk of postoperative SIJP. These slides can be retrieved under Electronic Supplementary Material.

Correlation of Functional Outcomes and Sagittal Alignment After Long Instrumented Fusion for Degenerative Thoracolumbar Spinal Disease

STUDY DESIGN

A retrospective function and radiography study of the patients who have received long instrumented thoracolumbar fusion.

OBJECTIVE

To investigate the correlation between the sagittal spinopelvic alignment and the functional outcomes after long instrumented fusion for degenerative thoracolumbar spinal disease.

SUMMARY OF BACKGROUND DATA

Restoring better sagittal alignment is known as a key factor to spine fusion surgeries. The relationship between function and radiographic results in the elderly group is barely known.

METHODS

Between 2009 and 2013, data of 120 patients with multilevel degenerative thoracolumbar spinal disease who underwent long instrumented fusion were collected retrospectively. Perioperative radiographic and functional parameters were measured and analyzed for their correlations. Receiver operating characteristic (ROC) method was used to define ideal cutoff points of postoperative spinopelvic alignment to avoid poor outcome.

RESULTS

Oswestry disability index (ODI) more than or equal to 20 or Visual analogue scale (VAS) more than or equal to 4 were defined as poor functional outcomes. The optimal cutoff points of the radiographic parameters were found as below: the mismatch between pelvic incidence and lumbar lordosis was 16.2°, sagittal vertical axis was 38.5 mm, and pelvic tilt was 23.4°. Poor functional outcomes were significantly correlated with bad sagittal alignment, older age, and poor preoperative function.

CONCLUSION

Postoperative functional outcomes were highly impacted by the spinopelvic sagittal alignment.

LEVEL OF EVIDENCE

4.

Sagittal lumbopelvic alignment in patients with low back pain and the effects of a high-load lifting exercise and individualized low-load motor control exercises-a randomized controlled trial

BACKGROUND CONTEXT

Assessment of posture and lumbopelvic alignment is often the main focus in the classification and treatment of patients with low back pain (LBP). However, little is known regarding the effects of motor control interventions on objective measures of lumbopelvic alignment.

PURPOSE

The primary aim of this study was to describe the variation of sagittal lumbopelvic alignment in patients with nociceptive mechanical LBP. The secondary aim was to compare the effects of a high-load lifting exercise (HLL) and low-load motor control exercises (LMC) on the change in lumbopelvic alignment with a special emphasis on patients with high and low degrees of lumbar lordosis (lu) and sacral angle (sa).

STUDY DESIGN

This study is a secondary analysis of a randomized controlled trial evaluating the effects of HLL and LMC.

PATIENT SAMPLE

Patients from the primary study, that is, patients categorized with nociceptive mechanical LBP, who agreed to participate in the radiographic examination were included (n=66).

OUTCOME MEASURES

Lateral plain radiographic images were used to evaluate lumbopelvic alignment regarding the lumbar lordosis and the sacral angle as outcomes, with posterior bend as an explanatory variable.

MATERIALS AND METHODS

The participants were recruited to the study from two occupational health-care facilities. They were randomized to either the HLL or the LMC intervention group and offered 12 supervised exercise sessions. Outcome measures were collected at baseline and following the end of intervention period 2 months after baseline. Between- and within-group analyses of intervention groups and subgroups based on the distribution of the baseline values for the lumbar lordosis and the sacral angle, respectively (LOW, MID, and HIGH), were performed using both parametric and non-parametric statistics.

RESULTS

The ranges of values for the present sample were 26.9-91.6° (M=59.0°, standard deviation [SD]=11.5°) for the lumbar lordosis and 18.2-72.1° (M=42.0°, SD=9.6°) for the sacral angle. There were no significant differences between the intervention groups in the percent change of eitheroutcome measure. Neither did any outcome change significantly over time within the intervention groups. In the subgroups, based on the distribution of respective baseline values, LOW_lu showed a significantly increased lumbar lordosis, whereas HIGH_sa showed a significantly decreased sacral angle following intervention.

CONCLUSIONS

This study describes the wide distribution of values for lumbopelvic alignment for patients with nociceptive mechanical LBP. Further research is needed to investigate subgroups of other types of LBP and contrast findings to those presented in this study. Our results also suggest that retraining of the lumbopelvic alignment could be possible for patients with LBP.

How does the sagittal spinal balance of the scoliotic population deviate from the asymptomatic population?

Background

Previously, the sagittal spinal balance in both asymptomatic and scoliotic Caucasian people has been characterized and compared. Very recently, the sagittal spino-pelvic parameters among asymptomatic Chinese adults have been studied, and the results were compared with Caucasian adults, indicating that a difference did exist. Unfortunately, the distribution of sagittal standing posture patterns among the Chinese population has not been characterized in either asymptomatic or scoliotic groups.

Methods

We conducted a radiographic comparison study to define the deviation of sagittal balance in scoliotic patients from that of an asymptomatic population. A total of 126 asymptomatic and 117 idiopathic scoliotic (IS) young adults were recruited. Radiographic data from each subject were reviewed, and sagittal spinopelvic parameters were measured. The Roussouly type was then determined, as well as the relative position of the C7 plumbline with respect to the sacrum and hip axis. Comparison analyses were undertaken between the two different groups.

Results

The IS group had a larger pelvic incidence, pelvic tilt and sacral slope, but a smaller spinal tilt than the asymptomatic group (P < 0.05), while other sagittal parameters were similar. The distribution of Roussouly types was similar between the asymptomatic and IS groups, of which 49.2% and 45.3% belonged to Roussouly Type 3, respectively. Asymptomatic males and females had a similar distribution, which was different between the two genders in the IS group (P < 0.05), with more females possessing a neutral sagittal standing posture. In addition, more IS subjects had forward displacement of the C7 plumbline than asymptomatic ones (P < 0.05), while there was no difference between the two genders in either group.

Conclusions

Although sagittal pelvic parameters were greater in the IS population, their sagittal spinal balance was maintained and there was no sagittal standing posture pattern correlated with IS. The occurrence of anterior displacement of the C7 plumbline was more common in IS patients than asymptomatic adults, but did not appear to be correlated with gender in both populations.

The association of kyphosis assessed in supine and standing positions with future activities of daily living dependence: the Kurabuchi Study

We investigated the longitudinal association of noninvasively evaluated kyphotic posture with future dependence in activities of daily living and death in a community-dwelling older Japanese. We found that the association with outcomes varied according to the types of kyphotic posture.

INTRODUCTION

We have previously found an association between severe kyphosis and future dependence in activities of daily living (ADL) in people who manifest the condition in the supine position (structural curvature). However, because some people show severe kyphosis only in the standing position (postural curvature), we combined our noninvasively obtained kyphosis measurements from participants in the supine position (block method) with those obtained from participants in the standing position (kyphosis index) to determine whether not only structural curvature but also postural curvature is associated with ADL dependence and death.

METHODS

Between 2005 and 2006, we carried out health evaluations of adults aged 65 years or older in Kurabuchi Town, Japan: 792 participants (337 males, 455 females) who were independent in ADL at baseline and underwent evaluation of kyphotic posture were followed up until March 2014 (mean follow-up: 7.5 years). Participants who experienced one or more admissions to a nursing home, certification of a need for long-term care/support, or a decline in the Katz ADL Index during the follow-up period were defined as being dependent in ADL.

RESULTS

A flat back (straight spine in a standing position) and structural curvature were associated with future ADL dependence, but postural curvature was not. The multivariate-adjusted odds ratios (95% confidence interval) compared with physiological curvature (physiological curvature in a standing position) as the reference were 1.72 (1.04-2.86) for a flat back and 2.76 (1.59-4.79) for structural curvature. A weak association with death was observed in those with structural curvature.

CONCLUSIONS

Our results suggest that the prognoses of people with kyphosis differ according to the type of kyphotic posture.

The distribution of lumbar intervertebral angles in upright standing and extension is related to low back pain developed during standing

BACKGROUND

Lumbar lordosis measures are poorly related to clinical low back pain, however using a controlled exposure such as prolonged standing to identify pain groups may clarify this relationship. The purpose of this study was to determine the distribution of lumbar intervertebral angles in asymptomatic persons who do (pain developers) and do not (non-pain developers) develop low back pain during standing.

METHODS

Sagittal plane lumbar spine radiographs of eight pain developers and eight non-pain developers were taken in three poses: upright standing, full extension and full flexion. Measures of vertebral end plate orientations from L1 to S1 were taken in each pose to compute: intervertebral angles, contribution of each level to the total curve, total lordosis, ranges of motion, relative pose positioning within the range of motion, vertebral shape, and lumbar spine recurve. Measures were compared between pain groups and lumbar levels.

FINDINGS

Pain group differences in intervertebral angles and level contributions were greatest in the full extension pose, with pain developers having greater contributions from higher lumbar levels and fewer contributions from lower levels than non-pain developers. Pain group differences in intervertebral angle distributions were less pronounced in upright standing and non-existent in full flexion. No other measures differentiated pain groups.

INTERPRETATIONS

Although participants had similar gross-lumbar spine curvature characteristics, non-pain developers have more curvature at lower levels in upright standing and full extension. These differences in regional vertebral kinematics may partially be responsible for standing-induced low back pain.

Pelvic Incidence Can Be Changed not only by Age and Sex, but also by Posture Used during Imaging

OBJECTIVE

Computed tomography (CT), rather than conventional 2-dimensional radiography, was used to scan and measure pelvic parameters. The results were compared with measurements using X-ray.

METHODS

Pelvic parameters were measured using both CT and X-ray in 254 patients who underwent both abdomino-pelvic CT and X-ray at the pelvic site. We assessed the similarity of the pelvic parameters between the 2 exams, as well as the correlations of pelvic parameters with sex and age.

RESULTS

The mean values of the subjects' pelvic parameters measured on X-ray were: sacral slope (SS), 31.6°; pelvic tilt (PT), 18.6°; and pelvic incidence (PI), 50.2°. The mean values measured on CT were: SS, 35.1°; PT, 11.9°; and PI, 47.0°. PT was found to be 4.07° higher on X-ray and 2.98° higher on CT in women, with these differences being statistically significant (p<0.001, p<0.001). PI was 4.10° higher on X-ray and 2.78° higher on CT in women, with these differences also being statistically significant (p<0.001, p=0.009). We also observed a correlation between age and PI. For men, this correlation coefficient was 0.199 measured using X-ray and 0.184 measured using CT. For women, this correlation coefficient was 0.423 measured using X-ray and 0.372 measured using CT.

CONCLUSION

When measured using CT compared to X-ray, SS increased by 3.5°, PT decreased by 6.7°, and PI decreased by 3.2°. There were also statistically significant differences in PT and PI between male and female subjects, while PI was found to increase with age.

Associations of anthropometry since birth with sagittal posture at age 7 in a prospective birth cohort: the Generation XXI Study

OBJECTIVES

Adult sagittal posture is established during childhood and adolescence. A flattened or hypercurved spine is associated with poorer musculoskeletal health in adulthood. Although anthropometry from birth onwards is expected to be a key influence on sagittal posture design, this has never been assessed during childhood. Our aim was to estimate the association between body size throughout childhood with sagittal postural patterns at age 7.

DESIGN

Prospective cohort study.

SETTING AND PARTICIPANTS

A subsample of 1029 girls and 1101 boys taking part in the 7-year-old follow-up of the birth cohort Generation XXI (Porto, Portugal) was included. We assessed the associations between anthropometric measurements (weight, height and body mass index) at birth, 4 and 7 years of age and postural patterns at age 7. Postural patterns were defined using latent profile analysis, a probabilistic model-based technique which allows for simultaneously including anthropometrics as predictors of latent profiles by means of logistic regression.

RESULTS

Postural patterns identified were sway, flat and "neutral to hyperlordotic"in girls, and "sway to neutral", flat and hyperlordotic in boys; with flat and hyperlordotic postures representing a straightened and a rounded spine, respectively. In both girls and boys, higher weight was associated with lower odds of a flat pattern compared with a sway/"sway to neutral"pattern, with stronger associations at older ages: for example, ORs were 0.68 (95% CI 0.53 to 0.88) per SD increase in birth weight and 0.36 (95% CI 0.19 to 0.68) per SD increase in weight at age 7 in girls, with similar findings in boys. Boys with higher ponderal index at birth were more frequently assigned to the hyperlordotic pattern (OR=1.44 per SD; p=0.043).

CONCLUSIONS

Our findings support a prospective sculpting role of body size and therefore of load on musculoskeletal spinopelvic structures, with stronger associations as children get older.

Global tilt and lumbar lordosis index: two parameters correlating with health-related quality of life scores-but how do they truly impact disability?

BACKGROUND CONTEXT

Many radiological parameters have been reported to correlate with patient's disability including sagittal vertical axis (SVA), pelvic tilt (PT), and pelvic incidence minus lumbar lordosis (PI-LL). European literature reports other parameters such as lumbar lordosis index (LLI) and the global tilt (GT). If most parameters correlate with health-related quality of life scores (HRQLs), their impact on disability remains unclear.

PURPOSE

This study aimed to validate these parameters by investigating their correlation with HRQLs. It also aimed to evaluate the relationship between each of these sagittal parameters and HRQLs to fully understand the impact in adult spinal deformity management.

STUDY DESIGN

A retrospective review of a multicenter, prospective database was carried out.

PATIENT SAMPLE

The database inclusion criteria were adults (>18 years old) presenting any of the following radiographic parameters: scoliosis (Cobb ≥20°), SVA ≥5 cm, thoracic kyphosis ≥60° or PT ≥25°. All patients with complete data at baseline were included.

OUTCOME MEASURES

Health-related quality of life scores, demographic variables (DVs), and radiographic parameters were collected at baseline.

METHODS

Differences in HRQLs among groups of each DV were assessed with analyses of variance. Correlations between radiographic variables and HRQLs were assessed using the Spearman rank correlation. Multivariate linear regression models were fitted for each of the HRQLs (Oswestry Disability Index [ODI], Scoliosis Research Society-22 subtotal score, or physical component summaries) with sagittal parameters and covariants as independent variables. A p<.05 value was considered statistically significant.

RESULTS

Among a total of 755 included patients (mean age, 52.1 years), 431 were non-surgical candidates and 324 were surgical candidates. Global tilt and LLI significantly correlated with HRQLs (r=0.4 and -0.3, respectively) for univariate analysis. Demographic variables such as age, gender, body mass index, past surgery, and surgical or non-surgical candidate were significant predictors of ODI score. The likelihood ratio tests for the addition of the sagittal parameters showed that SVA, GT, T1 sagittal tilt, PI-LL, and LLI were statistically significant predictors for ODI score even adjusted for covariates. The differences of R² values from Model 1 were 1.5% at maximum, indicating that the addition of sagittal parameters to the reference model increased only 1.5% of the variance of ODI explained by the models.

CONCLUSION

GT and LLI appear to be independent radiographic parameters impacting ODI variance. If most of the parameters described in the literature are correlated with ODI, the impact of these radiographic parameters is less than 2% of ODI variance, whereas 40% are explained by DVs. The importance of radiographic parameters lies more on their purpose to describe and understand the malalignment mechanisms than their univariate correlation with HRQLs.

Lack of improvement in health-related quality of life (HRQOL) scores 6 months after surgery for adult spinal deformity (ASD) predicts high revision rate in the second postoperative year

PURPOSE

ASD is assessed radiologically with the spinopelvic parameters and clinically with HRQOL scores. The revision rate after ASD surgery is high and usually occurs during the first or second postoperative year. The aim of this study is to find clinical or radiological factors that could predict revision surgery in the second postoperative year.

MATERIALS AND METHODS

Inclusion criterion: ASD patients operated on by instrumented posterior fusion with more than 2 years follow-up were enrolled prospectively. Additional criterion was no revision surgery during the first postoperative year. From a multicenter database of 560 operated ASD patients, 164 patients met these criteria. The patients were divided into two groups depending on the need of revision surgery during the second postoperative year. Preoperative, 6-month, 1-year and 2-year data were collected and compared for both groups.

RESULTS

A total of 22 patients needed revision surgery and 142 did not. All revisions were for mechanical complications (non-fusion and implant related). Preoperatively, there was a significant difference between the groups (no revision vs. revision) for age (48 vs. 60 years), ODI (37 vs. 53), and SVA (29 vs. 76 mm), respectively. At 6 months, a significant difference in sagittal alignment was found, though HRQOL scores were similar. At 1 year, the no revision group scores improved, whereas the revision group scores remained stable or worsened. At 2 years, the no revision group scores remained stable. Comparing 6- and 12-month data, patients with improved, stable and worsened HRQOL scores had 8, 15 and 28% revision rates, respectively.

CONCLUSION

The revision rate at the second-year post-surgery (13.4%) remains high and demonstrated that a 2-year follow-up is mandatory. In addition to usual risk factors for mechanical complications in ASD surgery, stabilization or worsening of the HRQOL scores between the 6th and 12th month postop was highly predictive of revision rate. This observation is beneficial for ASD patient follow-up as clinical symptoms clearly precede mechanical failure.

Magnetic resonance spectroscopic analysis of multifidus muscles lipid content and association with spinopelvic malalignment in chronic low back pain

OBJECTIVE

To analyze intramyocellular lipids (IMCLs) and extramyocellular lipids (EMCLs) of the multifidus muscle (Mm) using MR spectroscopy in chronic low back pain (CLBP) and control groups and to identify correlations with spinopelvic alignment.

METHODS

40 patients (16 males, 24 females; mean age, 62.9 ± 1.9 years) whose visual analogue scale scores were >30 mm for CLBP were included. Furthermore, 40 control participants matched with the CLBP group subjects by sample size, gender and age (17 males, 23 females; mean age, 65.0 ± 1.2 years) were included. We compared the body mass index, physical workload, leisure time physical activity level, spinopelvic parameters, and IMCLs and EMCLs of the Mm between the groups. We also evaluated possible correlations of spinopelvic parameters with IMCLs and EMCLs of the Mm in the groups.

RESULTS

There were no statistically significant differences in body mass index, physical workload, exercise intensity level, spinopelvic parameters and EMCLs between the groups. The IMCLs were significantly higher in the CLBP group than in the control group (p < 0.01). In the CLBP group, there was a significantly negative correlation between IMCLs and lumbar lordosis (r = -0.64, p < 0.01) and a significantly positive correlation between IMCLs and sagittal vertical axis (r = 0.43, p < 0.01).

CONCLUSION

The measurement of IMCLs might be a characteristic finding of CLBP as well as a precursor to spinal deformity. Advances in knowledge: IMCLs of the Mm may be a useful prognostic marker in rehabilitation strategies for patients with CLBP.

Defining Patterns of Sagittal Standing Posture in Girls and Boys of School Age

Background

Sagittal postural patterns are associated with back pain in adolescents and adults. However, whether postural patterns are already observable during childhood is unknown. Such a finding would confirm childhood as a key period for posture differentiation and thus for chronic pain etiology.

Objective

The aims of this study were to identify and describe postural patterns in girls and boys of school age.

Design

This was a cross-sectional study.

Methods

Eligible children were evaluated at age 7 in the population-based birth cohort Generation XXI in Portugal. Posture was assessed through right-side photographs during habitual standing with retroreflective markers placed on body landmarks. Postural patterns were defined from trunk, lumbar, and sway angles with model-based clusters, and associations with anthropometric measures were assessed by multinomial logistic regression.

Results

Posture was evaluated in 1,147 girls and 1,266 boys. Three postural patterns were identified: sway (26.9%), flat (20.9%), and neutral to hyperlordotic (52.1%) in girls and sway to neutral (58.8%), flat (36.3%), and hyperlordotic (4.9%) in boys. In girls, a higher body mass index was associated with a sway pattern (versus a flat pattern: odds ratio = 1.21; 95% CI = 1.12, 1.29), whereas in boys, a higher body mass index was associated with a hyperlordotic pattern (versus a flat pattern: odds ratio = 1.30; 95% CI = 1.17, 1.44).

Limitations

Photogrammetry as a noninvasive method for posture assessment may have introduced some postural misclassifications.

Conclusions

Postural patterns in 7-year-old children were consistent with those previously found in adults, suggesting that childhood is a sensitive period for posture differentiation. Sagittal morphology differed between girls and boys, emphasizing sex-specific biomechanical loads during a habitual upright position even in prepubertal ages.

Reliability and Validity Measurement of Sagittal Lumbosacral Quiet Standing Posture with a Smartphone Application in a Mixed Population of 183 College Students and Personnel

Accurate recording of spinal posture with simple and accessible measurement devices in clinical practice may lead to spinal loading optimization in occupations related to prolonged sitting and standing postures. Therefore, the purpose of this study was to establish the level of reliability of sagittal lumbosacral posture in quiet standing and the validity of the method in differentiating between male and female subjects, establishing in parallel a normative database. 183 participants (83 males and 100 females), with no current low back or pelvic pain, were assessed using the “iHandy Level” smartphone application. Intrarater reliability (3 same-day sequential measurements) was high for both the lumbar curve (ICC_2,1: 0.96, SEM: 2.13°, and MDC_95%: 5.9°) and the sacral slope (ICC_2,1: 0.97, SEM: 1.61°, and MDC_95%: 4.46°) sagittal alignment. Data analysis for each gender separately confirmed equally high reliability for both male and female participants. Correlation between lumbar curve and sacral slope was high (Pearson's r = 0.86, p < 0.001). Between-gender comparisons confirmed the validity of the method to differentiate between male and female lumbar curve and sacral slope angles, with females generally demonstrating greater lumbosacral values (p < 0.001). The “iHandy Level” application is a reliable and valid tool in the measurement of lumbosacral quiet standing spinal posture in the sagittal plane.

Increased low back pain prevalence in females than in males after menopause age: evidences based on synthetic literature review

Female sex hormones play an important role in the etiology and pathophysiology of a variety of musculoskeletal degenerative diseases. Postmenopausal women show accelerated disc degeneration due to relative estrogen deficiency. This literature review aims to validate or falsify this hypothesis, i.e., while overall females have higher prevalence of low back pain (LBP) across all age groups, this male vs. female difference in LBP prevalence further increases after female menopause age. The literature search was performed on PubMed on January 2, 2016. The search word combination was (low back pain) AND prevalence AND [(males OR men) AND (females OR women)]. The following criteria were taken to include the papers for synthetic analysis: (I) only English primary literatures on nonspecific pain; (II) only prospective studies on general population, but not population with occupational LBP causes, of both males and female subjects studied using the same LBP criterion, ages-specific information available, and males and female subjects were age-matched; (III) studies without major quality flaws. In total 98 studies with 772,927 subjects were analyzed. According to the information in the literature, participant subjects were divided into four age groups: (I) school age children group: 6-19 years; (II) young and middle aged group: 20-50 years; (III) mixed age group: data from studies did not differentiate age groups; (IV) elderly group: ≥50 years old. When individual studies were not weighted by participant number and each individual study is represented as one entry regardless of their sample size, the median LBP prevalence ratio of female vs. males was 1.310, 1.140, 1.220, and 1.270 respectively for the four age groups. When individual studies were weighted by participant number, the LBP prevalence ratio of female vs. males was 1.360, 1.127, 1.185, and 1.280 respectively for the four groups. The higher LBP prevalence in school age girls than in school age boys is likely due to psychological factors, female hormone fluctuation, and menstruation. Compared with young and middle aged subjects, a further increased LBP prevalence in females than in males was noted after menopause age.

Analysis of Global Sagittal Postural Patterns in Asymptomatic Chinese Adults

Study Design

A prospective imaging study.

Purpose

To characterize the distribution of the global sagittal postural patterns in asymptomatic Chinese adults using Roussouly classification.

Overview of Literature

The norms of sagittal parameters in asymptomatic Chinese population have been previously described, but no report described their global sagittal postural patterns as characterized by Roussouly classification.

Methods

A cohort of 272 asymptomatic Chinese adults was recruited. Data was assimilated by reviewing the films for each subject. Sagittal parameters were measured and sagittal postural patterns were then determined according to Roussouly classification. The pattern distributions were compared across genders within the study cohort. We also compared the data across different ethnicities from our study and a previous study to further characterize Chinese sagittal postures.

Results

The cohort included 161 males and 111 females, with mean age of 23.2±4.4 years. The average descriptive results were as below: pelvic incidence (PI) 46.4°±9.6°, thoracic kyphosis (TK) 24.2°±9.0°, lumbar lordosis (LL) 50.6°±10.6°, sacral slope (SS) 37.2°±7.6°, pelvic tilt (PT) 9.4°±6.8°, spinosacral angle (SSA) 131.1°±7.5° and sagittal vertical axis (SVA) 17.24±32.36 mm. Despite a significant difference between two genders in LL, PI, SSA, and SVA, no difference was found in the distribution of Roussouly types among them. 47.8% of our cohort belonged to Roussouly type 3, while type 1, 2 and 4 comprised 23.2%, 14.0% and 15.1% of the subjects, respectively. Roussouly classification was capable of categorizing sagittal parameters except for the PT. This study also found that 4.4% of the recruited subjects belonged to the C7-anterior subgroup.

Conclusions

From a characterization of the sagittal postural patterns of asymptomatic Chinese adults using Roussouly classification, the distribution was similar between Chinese males and females; however, from a cross-study comparison, it was different between asymptomatic Chinese and Caucasian adults, with a higher proportion of Roussouly type 3 in Chinese adults.