SAM

Global Sagittal Angle and T9-tilt seem to be the most clinically and functionally relevant global alignment parameters in patients with Adult Spinal Deformity

NASSIM, Nabil — Mon, 01 Apr 2024 00:00:00 GMT

Global Sagittal Angle and T9-tilt seem to be the most clinically and functionally relevant global alignment parameters in patients with Adult Spinal Deformity NASSIM, Nabil; MEKHAEL, Elio; RACHKIDI, Rami El; SAADE, Maria; AYOUB, Elma; RTEIL, Ali; JABER, Elena; CHAAYA, Celine; REHAYEM, Rami; ABI NAHED, Julien; KARAM, Mohamad; GHANEM, Ismat; MASSAAD, Abir; ASSI, Ayman Introduction Radiographic analysis is necessary for the assessment and the surgical planning in adults with spinal deformity (ASD). Restoration of global alignment is key to improving patient's quality of life. However, the large number of existing global alignment parameters can be confusing for surgeons. Research question To determine the most clinically and functionally relevant global alignment parameters in ASD. Material and methods ASD and controls underwent full body biplanar X-ray to calculate global alignment parameters: odontoid to hip axis angle (OD-HA), global sagittal angle (GSA), global tilt (GT), SVA, center of auditory meatus to hip axis (CAM-HA), SSA, T1-tilt and T9-tilt. All subjects filled HRQoL questionnaires: ODI, SF-36, VAS for pain and BDI (Beck's Depression Inventory). 3D gait analysis was performed to calculate kinematic and spatio-temporal parameters. A machine learning model predicted gait parameters and HRQoL scores from global alignment parameters. Results 124 primary ASD and 47 controls were enrolled. T9 tilt predicted the most BDI (31%), hip flexion/extension during gait (36%), and double support time (39%). GSA predicted the most ODI (26%), thorax flexion/extension during gait (33%), and cadence (36%). Discussion and conclusion Among all global alignment parameters, GSA, evaluating both trunk shift and knee flexion, and T9 tilt, evaluating the shift of the center of mass, were the best predictors for most of HRQoL scores and gait kinematics. Therefore, we recommend using GSA and T9 tilt in clinical practice when evaluating ASD because they represent the most quality of life and functional kinematic of these patients.

Kinematic limitations during stair ascent and descent in patients with adult spinal deformity

FAKHOURY, Marc — Sun, 01 Dec 2024 00:00:00 GMT

Kinematic limitations during stair ascent and descent in patients with adult spinal deformity FAKHOURY, Marc; RACHKIDI, Rami; SEMAAN, Karl; ABI KARAM, Krystel; SAADÉ, Maria; AYOUB, Elma; CHAAYA, Celine; RTEIL, Ali; JABER, Elena; MEKHAEL, Elio; NASSIM, Nabil; KARAM, Mohamad; ABINAHED, Julien; GHANEM, Ismat; MASSAAD, Abir; ASSI, Ayman Background: Adults with spinal deformity (ASD) are known to have spinal malalignment, which can impact their quality of life and their autonomy in daily life activities. Among these tasks, ascending and descending stairs is a common activity of daily life that might be affected. Research question: What are the main kinematic alterations in ASD during stair ascent and descent? Methods: 112 primary ASD patients and 34 controls filled HRQoL questionnaires and underwent biplanar X-from which spino-pelvic radiographic parameters were calculated. Patients were divided into 3 groups: 44 with sagittal malalignment (ASD-Sag: PT > 25°, SVA>5 cm or PI-LL>10°), 42 with isolated thoracic hyperkyphosis (ASD-HyperTK: TK > 60°), 26 with isolated frontal spine deformity (ASD-Front: Cobb>20°). All participants underwent 3D motion analysis of the whole body while ascending and descending a stair step from which kinematic waveforms were extracted. Results: During stair ascent, ASD-Sag exhibited an increased thorax flexion (20 vs 5°), a decreased lumbar lordosis L1L3-L3L5 (7 vs 14°), and an increased ROM of lumbo-pelvic joint (15 vs 10°, all p < 0.05), compared to controls. Similar compensations were shown while descending the stairstep. ASD-HyperTK had similar kinematic limitations as ASD-Sag but to a lesser extent. ASD-Front had normal kinematic patterns. PCS-SF36 correlated to thorax flexion (r = -0.45) and ODI was correlated to pelvic tilt ROM (r = 0.46). Discussion and conclusion: ASD subjects with sagittal malalignment tend to ascend and descend stairs with increased thorax flexion, making them more prone to falls. Compensation mechanisms occur at the head and lumbo-pelvic levels to maintain balance and avoid falling forward.

Weak trunk extensors in adult spinal deformity patients are related to sagittal malalignment and kinematic limitations

SAADÉ, Maria — Wed, 01 Jan 2025 00:00:00 GMT

Weak trunk extensors in adult spinal deformity patients are related to sagittal malalignment and kinematic limitations SAADÉ, Maria; RACHKIDI, Rami; RTEIL, Ali; AYOUB, Elma; JABER, Elena; CHAAYA, Celine; NASSIM, Nabil; MEKHAEL, Elio; REHAYEM, Rami; NAHED, Julien Abi; RAMADAN, Bilal; KARAM, Mohamad; GHANEM, Ismat; MASSAAD, Abir; ASSI, Ayman Background: Adult spinal deformity (ASD) is associated with muscles' degeneration that affects postural control and outcomes of an eventual corrective surgery. Evaluation of ASD is usually based on static radiographs and more recently on functional assessment. However, there has been limited exploration of muscle strength weakness in ASD. The aim was to investigate the relationship between trunk muscles' strength in ASD and its relationship with radiographic and kinematic alterations and quality-of-life decline. Methods: 28 ASD and 18 asymptomatic subjects underwent biplanar radiographs with 3D calculation of spino-pelvic and global postural parameters. 3D movement analysis of gait, sitting to standing and stair ascent, was studied allowing the calculation of head, trunk and lower limbs 3D kinematics. Participants filled out health related quality of life questionnaires. A single operator measured 4 times the strength of the trunk muscles, using a hand-held dynamometer, to assess measurements' reliability. ASD population was divided into two groups based on the strength of trunk extensors: ASD-weak extensors (N = 11 patients having trunk extensors strength0.94). On standing radiographs, the ASD-weak extensors group showed an increased positive sagittal malalignment compared to the other groups (SVA=61 mm vs ASD-normal extensors: 18 mm, controls: -4 mm, p < 0.001). This sagittal malalignment remained during movement (kinematic-SVA=223 mm vs ASD-normal extensors:178 mm, controls:138 mm, p < 0.001). Muscle strength weakness was correlated to the decline of quality-of-life scores (PCS-SF36: r = 0.48, VAS for pain: ρ=-0.39). Conclusions: This study showed that weak trunk extensors are associated with sagittal malalignment in static position, kinematic limitations during daily life activities and reduced quality of life scores. Future studies will investigate the effect of muscle strengthening on both static and dynamic alignment in ASD and their quality of life.

ASD with high pelvic retroversion develop changes in their acetabular orientation during walking

ASSI, Ayman — Mon, 01 May 2023 00:00:00 GMT

ASD with high pelvic retroversion develop changes in their acetabular orientation during walking ASSI, Ayman; REBEYRAT, Guillaume; EL RACHKIDI, Rami; SEMAAN, Karl; SAAD, Eddy; MEKHAEL, Elio; NASSIM, Nabil; MASSAAD, Abir; LAFAGE, Virginie; GHANEM, Ismat; PILLET, Helene; SKALLI, Wafa Introduction: It was hypothesized that pelvic retroversion in Adult Spinal Deformity (ASD) can be related to an increased hip loading explaining the occurrence of hip-spine syndrome. Research question: How pelvic retroversion can modify acetabular orientation in ASD during walking? Methods: 89 primary ASD and 37 controls underwent 3D gait analysis and full-body biplanar X-rays. Classic spinopelvic parameters were calculated from 3D skeletal reconstructions in addition to acetabular anteversion, abduction, tilt, and coverage. Then, 3D bones were registered on each gait frame to compute the dynamic value of the radiographic parameters during walking. ASD patients having a high PT were grouped as ASD-highPT, otherwise as ASD-normPT. Control group was divided in: C-aged and C-young, age matched to ASD-hightPT and ASD-normPT respectively. Results: 25/89 patients were classified as ASD-highPT having a radiographic PT of 31° (vs 12° in other groups, p < 0.001). On static radiograph, ASD-highPT showed more severe postural malalignment than the other groups: ODHA = 5°, L1L5 = 17°, SVA = 57.4 mm (vs 2°, 48° and 5 mm resp. in other groups,all p < 0.001). During gait, ASD-highPT presented a higher dynamic pelvic retroversion of 30° (vs 15° in C-aged), along with a higher acetabular anteversion of 24° (vs 20°), external coverage of 38° (vs 29°) and a lower anterior coverage of 52° (vs 58°,all p < 0.05). Conclusion: ASD patients with severe pelvic retroversion showed an increased acetabular anteversion, external coverage and lower anterior coverage during gait. These changes in acetabular orientation, computed during walking, were shown to be related to hip osteoarthritis.

Kinematic adaptations from self-selected to fast speed walking in patients with adult spinal deformity

ABI KARAM, Krystel — Mon, 01 Jan 2024 00:00:00 GMT

Kinematic adaptations from self-selected to fast speed walking in patients with adult spinal deformity ABI KARAM, Krystel; EL RACHKIDI, Rami; SEMAAN, Karl; SAAD, Eddy; FAKHOURY, Marc; SAADE, Maria; AYOUB, Elma; RTEIL, Ali; JABER, Elena; MEKHAEL, Elio; NASSIM, Nabil; MASSAAD, Abir; GHANEM, Ismat; ASSI, Ayman Purpose To investigate kinematic adaptations from self-selected to fast speed walking in ASD patients. Methods 115 primary ASD and 66 controls underwent biplanar radiographic X-rays and 3D gait analysis to calculate trunk, segmental spine and lower limb kinematics during self-selected and fast speed walking. Kinematic adaptation was calculated as the difference (Δ) between fast and self-selected speed walking. ASD with 7 or more limited kinematic adaptation parameters were classified as ASD-limited-KA, while those with less than 7 limited kinematic adaptation parameters were classified as ASD-mild-KA. Results 25 patients were classified as ASD-limited-KA and 90 as ASD-mild-KA. ASD-limited-KA patients walked with a lesser increase of pelvic rotation (Δ = 1.7 vs 5.5°), sagittal hip movement (Δ = 3.1 vs 7.4°) and shoulder–pelvis axial rotation (Δ = 3.4 vs 6.4°) compared to controls (all p < 0.05). ASD-limited-KA had an increased SVA (60.6 vs − 5.7 mm), PT (23.7 vs 11.9°), PI–LL (9.7 vs − 11.7°), knee flexion (9.2 vs − 0.4°) and a decreased LL (44.0 vs 61.4°) compared to controls (all p < 0.05). Kinematic and radiographic alterations were less pronounced in ASD-mild-KA. The limited increase of walking speed was correlated to the deteriorated physical component summary score of SF-36 (r = 0.37). Discussion Kinematic limitations during adaptation from self-selected to fast speed walking highlight an alteration of a daily life activity in ASD patients. ASD with limited kinematic adaptations showed more severe sagittal malalignment with an increased SVA, PT, PI–LL, and knee flexion, a decreased LL and the most deteriorated quality of life. This highlights the importance of 3D movement analysis in the evaluation of ASD.

Head and pelvis are the key segments recruited by adult spinal deformity patients during daily life activities

AYOUB, Elma — Sun, 01 Sep 2024 00:00:00 GMT

Head and pelvis are the key segments recruited by adult spinal deformity patients during daily life activities AYOUB, Elma; RTEIL, Ali; CHAAYA, Celine; RACHKIDI, Rami; SAADE, Maria; JABER, Elena; MEKHAEL, Elio; NASSIM, Nabil; REHAYEM, Rami; KARAM, Mohammad; BIZDIKIAN, Aren Joe; GHANEM, Ismat; SKALLI, Wafa; MASSAAD, Abir; ASSI, Ayman Functional assessment is a key element in evaluating adult spinal deformity (ASD) patients. The multitude of 3D kinematic parameters provided by movement analysis can be confusing for spine surgeons. The aim was to investigate movement patterns of ASD based on key kinematic parameters. 115 primary ASD and 36 controls underwent biplanar radiographs and 3D movement analysis during walking, sit-to-stand and stair ascent to calculate joint and segment kinematics. Principal component analysis was applied to identify the most relevant kinematic parameters that define movement strategies adopted by ASD. Pelvis and head relative to pelvis kinematics were the most relevant parameters. ASD patients adopted four different movement strategies. Class 1: normative head and pelvis kinematics. Class 2: persistent pelvic backward tilt. Class 3: persistent forward shift of the head. Class 4: both pelvic backward tilt and forward shift of the head. Patients in class 3 and 4 presented sagittal malalignment on static radiographs with increased pelvic tilt, pelvic incidence-lumbar lordosis mismatch and sagittal vertical axis. Surprisingly, patients in class 3 had normal pelvic kinematics during movement, showing the importance of functional evaluation. In addition to being key segments in maintaining static global posture, head and pelvis were found to define movement patterns.

Different kinematic strategies are adopted by AIS patients during walking depending on Lenke type

R KARAM, Maria — Wed, 01 Jan 2025 00:00:00 GMT

Different kinematic strategies are adopted by AIS patients during walking depending on Lenke type R KARAM, Maria; ASMAR, Maria; EL RACHKIDI, Rami; WAKIM, Emmanuelle; MASSAAD, Abir; KARAM, Mohamad; EL HADDAD, Georges; BOUTROS, MARC; MRAD, Marc; HAMATI, Ibrahim; PRINCE, Gilles; RTEIL, Moustapha; AWAD, Guy; AZAR, Joe; RASSAM, Maria; HOYEK, Karim; EL HAYEK, Rony; MEKHAEL, Elio; NASSIM, Nabil; VERGARI, Claudio; PILLET, Helene; GHANEM, Ismat; ASSI, Ayman Introduction Adolescent Idiopathic Scoliosis (AIS) is classically evaluated through static X-rays and health-related quality of life questionnaires that do not reflect the functional limitations of patients during daily life activities, such as walking. The aim was to investigate kinematic strategies in non-operated AIS with different types of curvature during walking using 3D gait analysis. Methods 13 AIS with Lenke 5 (major Cobb: 23 ± 8°), 30 AIS with Lenke 1 (major Cobb: 40 ± 14°) in addition to 24 controls underwent biplanar X-rays followed by 3D gait analysis. The kinematic parameters of the head, trunk, spinal segments, pelvis and lower limbs were compared between groups. Results AIS Lenke 5 had a lumbar segment bending while walking (T12L3-L3L5: 5 ± 7° vs. -3 ± 7° in controls) to the concave side of the scoliosis. They walked with an increased pelvic frontal mobility (12 ± 3° vs. 9 ± 3°) and internal rotation of the right foot (-2 ± 6° vs. -11 ± 8°; all p < 0.05). AIS Lenke 1 increased their thoracic & lumbar segment bending to the concave and to the opposite side respectively (T6T9-T9T12: -4 ± 9° vs. 1 ± 4°; T12L3-L3L5: 8 ± 12° vs. -2 ± 7°). However, they tended to reduce their lumbo-pelvic mobility (7 ± 5° vs. 12 ± 5°; all p < 0.05). Conclusion In response to their inherent lumbar stiffness and bending, AIS Lenke 5 patients tended to increase their pelvic frontal mobility and to develop a homolateral internal foot rotation, ensuring a dynamic alignment during gait. AIS Lenke 1, by producing opposite bending movement at the thoracic and lumbar segments, tended to reduce their lumbo-pelvic mobility and ensure coronal dynamic alignment.