Iliopectineal line: A valuable radiological reference for spino-pelvic parameters

Objectives: Spinopelvic parameters are crucial to address sagittal spinal imbalance; such measurements require standardized lateral radiographs that include spine and hips, which are neither always available, nor readily feasible intra-operatively. The aim of this study was to describe pelvic radiological reference points that could provide reliable sagittal balance estimates from conventional lumbosacral lateral radiographs. Methods: A descriptive, cross-sectional, radiological-based study was conducted. Readings were taken from institute’s digital radiology library, blinded to personal and clinical data. The correlation was made to conventional pelvic incidence (CPI), conventional pelvic tilt (CPT), and sacral slope (SS), measured for the same patients, and from the same standardized standing radiographs that included femoral heads. Results: Radiological images for 140 adult subjects, with suspected or established spine problems were studied. The average lumbar lordosis (LL) of 3 readers was 47 ± 13 (13–81) with an interclass agreement of 0.9, SS was 41 ± 9 with an interclass agreement of 0.9, CPI was 53 ± 10 with an interclass agreement of 0.8, CPT was 14 ± 8 with an interclass agreement of 0.9, iliopectineal inclination (IPI) of 4 readers was 64 ± 8 with an interclass agreement of 0.7 and iliopectineal tilt (IPT) was 24 ± 8 with an interclass agreement of 0.8 LL was with 6° of CPI and 16° of IPI. The CPI was equal to (CPI = SS + [CPT + 1.2]) and (IPI = SS + [IPT + 0.6]). The IPI was negatively correlated with CPI –0.2 P = 0.006, and IPI was negatively correlated with CPT –0.333 P < 0.001. Conclusion: Iliopectineal line provides reproducible readings, closer values to LL, and addresses the center of mass displacement.

The Morphological Changes in Adjacent Segments Amongst Patients Receiving Anterior and Oblique Lumbar Interbody Fusion: A Retrospective Study

Adjacent segment disease (ASD) is troublesome condition that has proved to be highly related to spinal malalignment after spinal surgery. Hence, we aimed to evaluate the morphological changes after anterior lumbar interbody fusion (ALIF) and oblique LIF (OLIF) to establish the differences between the two surgical methods in terms of possible ASD avoidance. Fifty patients, half of whom received ALIF while the other half received OLIF, were analyzed with image studies and functional outcomes during the pre-operative and post-operative periods, and 2 years after surgery. Image measurements obtained included spinal-pelvic parameters, index lordosis (IL), segmental lordosis (SL), anterior disc height (ADH), posterior disc height (PDH) and adjacent segment disc angle (ASDA). The ADH and PDH in the adjacent segment decreased in the two groups while OLIF showed greater decrease without radiological ASD noted at 2-year follow-up. Both groups showed an increase in IL after surgery while ALIF showed greater improvement. No statistical difference was identified in functional outcomes between LIFs. We suggest that both ALIF and OLIF can restore adequate lordosis and prevent ASD after surgery. However, it should be noted that patient selection remains crucial when making any decision involving which of the two methods to use.

Comparative Study of Spino-pelvic Parameters between Scoliotic versus Non-scoliotic Patients with Multi-level Degenerative Lumbar Spondylosis

Degenerative lumbar scoliosis is a multi-planner deformity seen in the aging spine. Important parameters in the evaluation of balance of the degenerative lumbar scoliosis include spino-pelvic parameters such as the LL, SS, PI, and PT besides the coronal Cobb´s angle. In order to minimize the energy associated with maintaining upright posture, sagittal balance is necessary. Significant sagittal abnormality or imbalance is commonly related to poor functional scores across multiple domains. Aim: The aim of this study was to investigate the role of the spino-pelvic parameters in the development of scoliosis in multi-level degenerative lumber spondylosis disease. Patients and Methods: This cross-sectional study was carried out in Tanta University Hospitals. It included the first 100 patients who visited the outpatient orthopedic department clinic from April 2019. Results: There was a statistically significant (p ≤ 0.05) increase in each of the PI, PT and cobb´s angle and a significant decrease in SS in multi-level DLS with scoliosis patients in correlation to multi-level DLS without scoliosis patients. There were no significant differences between LL in both studied groups. Regarding the age, sex, BMI and occupation in the two studied groups, there were no statistically significant differences. There was a significant correlation between the sex and PT in patients with multi-level DLS without scoliosis, but there was no significant correlation between sex and other parameters in both groups. There wasn´t significant correlation between the two groups by increasing the age. Manual workers in scoliotic group show higher PT and smaller SS than in non-scoliotic group, which give a significant correlation between the occupation and these spino-pelvic parameters. Conclusion: Importance of a thorough discussion of the risks of deformity progression weighed against the anticipated benefits with patient’s during clinical consultation return to the spino-pelvic parameters. Measurement of these spino-pelvic parameters can help in monitoring progression of disease in patients and allow physicians to provide better prevention, treatment and control.

Coronal and Sagittal Balance of Spine in Patients with Developmental Dysplasia of the Hip

Objective: To explore the spino-pelvic alignment changes in patients with Developmental dysplasia of the hip (DDH) and the effect of Total hip arthroplasty (THA) on the spino-pelvic alignment.Methods: In this study, patients with DDH are selected as the study group and healthy adults are selected as the control group. The differences of sagittal spino-pelvic parameters between patients with DDH and healthy adults are compared by independent sample t-test. Paired sample t-test is performed for spine-pelvis parameters before and after THA. Pearson correlation analysis is used to analyze the correlation about coronal spine-pelvic parameters. SPSS 22.0 software is used for statistical analysis, and p < 0.05 is the result of statistical significance.Results: In this study, there are 48 patients with DDH in study group, with an average age of 43.1±10.3 years old, consist of 42 females and 6 males. SVA =-4.1±33.9 mm, PI=42.9±18.9°, PT=4.6±15.6°, SS=38.2±13.9°, LL=53.3±12.6°, TK=22.8±9.2°, TLK=6.7±5.7°. There are 214 subjects in control group, SVA=-11.3±28.9mm, PI=45.6±9.4°, PT=9.9±6.8°, SS=35.5±7.1°, LL=48.4±10.8°, TK=27.7±10.4°，TLK=5.7±10°. The differences of SVA, PT, LL and TK were statistically significant. Before THA, IO = 6.7 ± 4.6°, SO = 6.4 ± 5.4°, HO = 5.3 ± 5.8°, L5O = 6.1 ± 5.5°, Cobb angle = 11.0 ± 10.7°; After THA, IO=3.5 ± 3°, SO=3.7 ± 3.4°, HO=3.7 ± 3.6°, L5O= 4.3 ± 4.7°, Cobb angle = 6.8±7.7°. The Cobb angle is related to SO and IO respectively (r=0.610, r=0.570). Conclusions: Due to acetabular dysplasia and dislocation of hip joint, patients with DDH will have changes in sagittal and coronal spino-pelvic alignment. In sagittal plane, PT is decreased, TK is decreased and LL is increased. And THA cannot correct the sagittal spino-pelvic alignment in patients with DDH. In coronal plane, there are Leg length discrepancy (LLD) and hip dislocation in patients with DDH, which together lead to coronal pelvic obliquity (PO). The overall coronal imbalance tendency caused by PO leads to compensatory scoliosis. And THA can significantly improve the degree of PO and compensatory scoliosis in patients with DDH.

1450 Relationship between Spinopelvic Parameters and Symptomatic Femoroacetabular Impingment: A Scoping Review

Aim Reports have shown that spinopelvic mobility influences the outcome following total hip arthroplasty. The aim of this scoping review was to investigate the relationship between spinopelvic parameters (SPP) and symptomatic femoroacetabluar impingement (FAI). Method A systematic computer search of EMBASE, PubMed and Cochrane for literature related to SPPs and FAI was undertaken as per PRISMA guidelines. Clinical outcome studies and prospective/retrospective studies that investigated the role of SPPs in symptomatic FAI were included. Review articles, case reports and book chapters were excluded. Information extracted pertained to symptomatic cam deformities, pelvic tilt, deviations in acetabular version, decreases in pain-free hip range of motion (ROM) on dynamic hip movements and radiological signs of FAI. Results The literature search identified 46 papers out of 1168 investigating the link between SPPs and pathological processes characteristic of FAI. Anteior pelvic tilt was associated with radiographic over-coverage parameters of FAI. Three studies associated FAI pathology with a greater pelvic incidence (PI), while four associated it with a smaller PI. In dynamic movements, decreased posterior pelvic tilt and reduced saggital pelvic ROM was found in symptomatic FAI patients during hip flexion. Conclusions Our study shows that spinopelvic parameters can influence radiological and clinical manifestations of FAI, with pelvic incidence, acetabular version and muscular imbalances being aetiologically implicated. Individual spinopelvic mobility may predispose to the development of FAI, which may be amenable to non-surgical management. If FAI pathoanatomy already exists however, sagittal pelvic parameters can influence whether FAI symptoms develop, and the extent to which they do so.

The compensatory mechanisms for global sagittal balance in degenerative spinal kyphosis patients: a radiological analysis of muscle-skeletal associations

Background The position of the head relative to the spine can be used to evaluate the true global balance in patients with degenerative spinal kyphosis (DSK). However, it is still not clear how the position of the head is related to the spinal-pelvic parameters and lumbar muscles, which are most commonly considered. Methods Sixty-seven patients with DSK admitted in the hospital from January 2017 to January 2019 were retrospectively analyzed. All patients had whole spine X-ray and lumbar MRI. The head position parameters include: the angles of both lines joining the center of acoustic meati (CAM) to the center of the bi-coxofemoral axis (BA) (CAM-BA) and the most superior point of dentiform apophyse of C2 odontoid (OD) to BA (OD-BA) with the vertical line; the distance between the vertical line passing CAM and the posterior upper edge of the S1 (CAM-SVA). The spinal parameters include: C7 sagittal vertical axis (C7-SVA), thoracic kyphosis (TK), thoracolumbar kyphosis (TLK), and lumbar lordosis (LL). The pelvic parameters include: pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS). The relative cross-sectional area (RCSA) of bilateral multifidus, erector spinae and psoas muscle at L3/4 and L4/5 segments were measured. The correlations between head position parameters and the spinal-pelvic parameters and RCSA of lumbar muscles were analyzed, respectively. Results Significant positive correlations were found between each two of CAM-SVA, C7-SVA, CAM-BA and OD-BA (p < 0.001). SS was found to be significantly positively correlated with CAM-BA (r = 0.377, p = 0.034) and OD-BA (r = 0.402, p = 0.023). CAM-BA was found to be significantly negatively correlated with TK (r = − 0.367, p = 0.039). Significant positive correlations were found between RCSA of multifidus at L3/4 level and CAM-SVA (r = 0.413, p = 0.021), CAM-BA (r = 0.412, p = 0.019) and OD-BA (r = 0.366, p = 0.04). Conclusions Our study showed that the head position relative to the spine were significantly correlated to some spinal-pelvic parameters, and the lower lumbar multifidus muscle. The compensatory mechanisms of the global sagittal balance status should also involve the head position area.

Stature estimation study based on pelvic and sacral morphometric among Malaysian population

Background Virtual anthropology in estimating stature through multislice computed tomography scanning is important for forensic cases and mass disasters. Regression formulae generated directly from other post-cranial skeleton parts can be applied for estimating stature. Literatures have revealed that scoring of pelvic shape in both sexes is significantly correlated with stature. Hereafter, this study aims to correlate the pelvic and sacral morphometric with stature based on sex and ancestry among the Malaysian population from the selected samples of 373 CT images at Kuala Lumpur Hospital. The three-dimensional pelvic girdles were first segmented from CT images through Mimics Research 17.0 software. Inter-landmark distances were measured with Microsoft 3D Builder and their respective indexes were computed. Results This study showed that the auricular lengths, ilium dimension and acetabulum were the most useful stature estimator at R > 0.5. The combination of pelvic parameters, sacral parameters and indexes had contributed to a higher R2 value of the regression models. Conclusions Pelvic morphometric was generally a better stature estimator compared to sacral morphometric. The population-specific formula produced from this study should only be realistic within the Malaysian population. This helps to enhance the existing references for stature estimation especially when incomplete human remains are discovered.

The radiographic assessments of spino-pelvic compensation using IoT-based real-time ischial pressure adjustment: clinical research study

Background: In malalignment syndrome, the spino-pelvic alignment correction with foot orthotics can be applied only to a standing position in the coronal plane. Considering the fact that the average time Koreans spend sitting in a chair is 7.5 hours per day, studies on spino-pelvic correction in sitting position is needed. The purpose of this study is to investigate the pressure changes and radiographic assessment of spino-pelvic alignment using a chair equipped with a height-adjustable seat-plate.Methods: Experiments were conducted on 30 research participants. The inclusion criteria for the participants were as follows: The volunteers of nonstructural malignment syndrome with shoulder height differences (SHDs) or iliac flea height differences (ICHDs) greater than 5 mm in radiographic images excluding participants with structural deformity. All participants were subjected to measure buttocks interface pressure while seated using a smart chair in three consecutive steps: (1) on initial seated, (2) on balancing seated, and then (3) on 1hr balancing seated. Radiographically, the five spino-pelvic parameters such as SHD, ICHD, LLD, POA, and coronal imbalance were analyzed to investigate the effect of pelvic imbalance compensation on spino-pelvic alignment.Results: Pelvic imbalance was compensated with seat plate height adjustment in average of 3.6 ± 1.8 mm, so that the pressure discrepancy improvement between buttocks from 36.4 ± 32.3 on initial seated to 15.7 ± 20.3 on balancing, 12.7 ± 10.9 on 1hr balancing seated (Ω, p=0.008). The radiographic changes before and after pelvic imbalance compensation demonstrated a statistically significant improvements of spino-pelvic parameters on sitting and standing: at the average value of -0.9 to -0.8 and 9.5 to 2.5, SHD and ICHD, respectively (mm, p=0.005, 0.037) and -3.0 to -1.0, 1.8 to 0.8, and 0.8 to 0.1, SHD, ICHD, and LLD, respectively (mm, p=0.005, 0.016, 0.033).Conclusions: Spino-pelvic malalignment can be improved by individually customized pelvic compensation using balanced seat plate height adjustments under the real-time pressure sensing and monitoring on the buttocks while seated.