Spine, Pelvis and Hip Kinematics—Characterizing the Axial Plane in Healthy and Osteoarthritic Hips

Abnormal spinopelvic movements are associated with inferior outcomes following total hip arthroplasty (THA). This study aims to (1) characterize the agreement between dynamic motion and radiographic sagittal assessments of the spine, pelvis, and hip; (2) determine the effect of hip osteoarthritis (OA) on kinematics by comparing healthy individuals with pre-THA patients suffering from uni- or bilateral hip OA. Twenty-four OA patients pre-THA and eight healthy controls underwent lateral spinopelvic radiographs in standing and seated bend-and-reach (SBR) positions. Lumbar-lordosis (LL), sacral-slope (SS), and pelvic–femoral (PFA) angles were measured in both positions, and the differences (Δ) between SBR and standing were computed to assess spine flexion (SF), pelvic tilt (PT), and hip flexion (HF), respectively. Dynamic SBR and seated maximal trunk rotation (STR) tasks were performed at the biomechanics laboratory. Peak sagittal and axial kinematics for spine, pelvis, and hip, and range of motion (ROM), were calculated for SBR and STR. Radiograph readings correlated with sagittal kinematics during SBR for ΔLL and SFmax (r = 0.66, p < 0.001), ΔPT and PTmax (r = 0.44, p = 0.014), and ΔPFA and HFmax (r = 0.70, p < 0.001), with a satisfactory agreement in Bland–Altman analyses. Sagittal SBR spinal (r = 0.33, p = 0.022) and pelvic (r =0.35, p = 0.018) flexions correlated with the axial STR rotations. All axial spinopelvic parameters were different between the OA patients and controls, with the latter exhibiting significantly greater mobility and less variability. Bilaterally affected patients exhibited lower peak and ROM compared to controls. The biomechanics laboratory performed reliable assessments of spinopelvic and hip characteristics, in which the axial plane can be included. The sagittal and axial pelvic kinematics correlate, illustrating that pelvic rotation abnormalities are likely also contributing to the inferior outcomes seen in patients with abnormal spinopelvic flexion characteristics. Axial rotations of the pelvis and spine were least in patients with bilateral hip disease, further emphasizing the importance of the hip–pelvic–spine interaction.

Do patients with well-functioning total hip arthroplasty achieve typical sagittal plane hip kinematics? A proof of concept study

Background: Total hip arthroplasty (THA) patients have been shown to not achieve normal sagittal plane hip kinematics. However, previous studies have only conducted group level analysis and as such lack the sensitivity to highlight whether individual patients do achieve normal hip kinematics. As such this study looked to determine whether some patients with well-functioning THA achieve typical sagittal plane hip kinematics. Methods: Sagittal plane hip kinematics were collected on 11 well-functioning THA patients (Oxford Hip Score = 46 ± 3) and 10 asymptomatic controls using a 3-dimensional motion analysis system during self-paced walking. High-functioning THA patients were identified as those who displayed sagittal plane hip kinematics that were within the variance of the control group on average, and low-functioning patients as those who did not. Results: 5 THA patients were identified as high-functioning, displaying hip kinematics within the variance of the control group. High-functioning THA patients displayed peak hip flexion and extension values more closely aligned to asymptomatic control group than low-functioning patients. However, hip range of motion was comparable between high- and low-functioning total hip arthroplasty patients and reduced compared to controls. Conclusion: The presence of high-functioning THA patients who display comparable sagittal plane hip kinematics to controls suggests these patients do achieve normative function and challenges the conclusions of previous group level analysis. Understanding why some patients achieve better function post-operatively will aid pre- and post-operative practices to maximise functional recovery.

Assessing Site Specificity of Osteoarthritic Gait Kinematics with Wearable Sensors and Their Association with Patient Reported Outcome Measures (PROMs): Knee versus Hip Osteoarthritis

There is a great need for quantitative outcomes reflecting the functional status in patients with knee or hip osteoarthritis (OA) to advance the development and investigation of interventions for OA. The purpose of this study was to determine if gait kinematics specific to the disease—i.e., knee versus hip OA—can be identified using wearable sensors and statistical parametric mapping (SPM) and whether disease-related gait deviations are associated with patient reported outcome measures. 113 participants (N = 29 unilateral knee OA; N = 30 unilateral hip OA; N = 54 age-matched asymptomatic persons) completed gait analysis with wearable sensors and the Knee/Hip Osteoarthritis Outcome Score (KOOS/HOOS). Data were analyzed using SPM. Knee and hip kinematics differed between patients with knee OA and patients with hip OA (up to 14°, p < 0.001 for knee and 8°, p = 0.003 for hip kinematics), and differences from controls were more pronounced in the affected than unaffected leg of patients. The observed deviations in ankle, knee and hip kinematic trajectories from controls were associated with KOOS/HOOS in both groups. Capturing gait kinematics using wearables has a large potential for application as outcome in clinical trials and for monitoring treatment success in patients with knee or hip OA and in large cohorts representing a major advancement in research on musculoskeletal diseases.

Subject-Specific Modeling of Femoral Torsion Influences the Prediction of Hip Loading During Gait in Asymptomatic Adults

Hip osteoarthritis may be caused by increased or abnormal intra-articular forces, which are known to be related to structural articular cartilage damage. Femoral torsional deformities have previously been correlated with hip pain and labral damage, and they may contribute to the onset of hip osteoarthritis by exacerbating the effects of existing pathoanatomies, such as cam and pincer morphologies. A comprehensive understanding of the influence of femoral morphotypes on hip joint loading requires subject-specific morphometric and biomechanical data on the movement characteristics of individuals exhibiting varying degrees of femoral torsion. The aim of this study was to evaluate hip kinematics and kinetics as well as muscle and joint loads during gait in a group of adult subjects presenting a heterogeneous range of femoral torsion by means of personalized musculoskeletal models. Thirty-seven healthy volunteers underwent a 3D gait analysis at a self-selected walking speed. Femoral torsion was evaluated with low-dosage biplanar radiography. The collected motion capture data were used as input for an inverse dynamics analysis. Personalized musculoskeletal models were created by including femoral geometries that matched each subject’s radiographically measured femoral torsion. Correlations between femoral torsion and hip kinematics and kinetics, hip contact forces (HCFs), and muscle forces were analyzed. Within the investigated cohort, higher femoral antetorsion led to significantly higher anteromedial HCFs during gait (medial during loaded stance phase and anterior during swing phase). Most of the loads during gait are transmitted through the anterior/superolateral quadrant of the acetabulum. Correlations with hip kinematics and muscle forces were also observed. Femoral antetorsion, through altered kinematic strategies and different muscle activations and forces, may therefore lead to altered joint mechanics and pose a risk for articular damage. The method proposed in this study, which accounts for both morphological and kinematic characteristics, might help in identifying in a clinical setting patients who, as a consequence of altered femoral torsional alignment, present more severe functional impairments and altered joint mechanics and are therefore at a higher risk for cartilage damage and early onset of hip osteoarthritis.

Comparison of 3D Hip Joint Kinematics in People with Asymptomatic Pronation of the Foot and Non-Pronation Controls

Background: The impact of asymptomatic pronation on proximal joints during motion has not been well understood, and research on it remains limited. Therefore, the current study determines the effect of asymptomatic pronation of the foot on hip joint kinematics during gait. Methods: Forty participants were recruited for the study (20 with asymptomatic pronated feet and 20 with non-pronated feet). Foot assessment was conducted by navicular drop and rear- foot angle tests. Hip joint kinematics were measured via MVN Xsens system 3D-motion capture from sagittal, frontal and transverse planes during gait. An independent t-test was used to identify differences in kinematic variables. Results: Both groups were similar in characteristics, and there were no significant differences between the groups in age (P = 0.674) and BMI (P = 0.459). However, there was a significant difference in arch height (P = 0.001) and rear-foot angle (P = 0.001). Our findings showed there were insignificant differences between the asymptomatic pronated foot and non- pronated foot control groups in hip joint kinematics of sagittal (P = 0.618), frontal (P = 0.276), and transverse (P = 0.337) planes during a full gait cycle. Conclusion: Patients with asymptomatic pronation of the foot and non-pronation of the foot showed similar movement patterns of hip kinematics in all three planes. The findings of the present study highlight the need for clinicians to consider foot alignment when examining patients with asymptomatic pronation of the foot and non-pronation of the foot.

Sex-Specific Hip Movement Is Correlated With Pelvis and Upper Body Rotation During Running

There is a sex bias for common overuse running injuries that are associated with sex-specific hip kinematics. Gait retraining programs aimed at altering hip kinematics may be more efficient if they incorporated an understanding of how hip kinematics are correlated with the movement of the remaining body segments. We applied a principal component analysis to structure the whole-body running kinematics of 23 runners (12 ♀) into k = 12 principal movements (PMk), describing correlated patterns of upper and lower body movements. We compared the time-dependent movement amplitudes with respect to each PMk between males and females using a waveform analysis and interpreted our findings according to stick figure animations. The movement amplitudes of two PMs (PM6 and PM8) showed statistically significant effects of “sex,” which were independent of running speed. According to PM8, females showed more hip adduction, which correlated with increased transverse rotation of the pelvis and upper body compared to men. We propose that increased hip adduction and upper body rotation in female runners may be a strategy to compensate for a less efficient arm and upper body swing compared to men. Gait interventions aimed at reducing hip adduction and running-related injuries in female runners should consider instructions for both upper and lower body to maximize training efficacy.

Comparison of Knee and Hip Kinematics during Landing and Cutting between Elite Male Football and Futsal Players

To design an accurate sport injury prevention program, alterations in the knee and hip kinematic variables involved in injury mechanisms should be known. The main purpose of the current study was to compare knee and hip kinematic variables during landing and cutting among male football and futsal players, and to discuss them within an injury description frame. Twenty football (20.5 ± 2.1 years., 74.5 ± 6.9 kg and 1.79 ± 0.07 m) and twenty futsal players (20.3 ± 2.0 years., 73.5 ± 7.1 kg and 1.78 ± 0.07 m), with at least three years’ experience of playing in the Kerman Province League, participated in this study. Hip flexion, knee flexion and knee valgus angle during two main movements with risk of injury, such as landing and cutting, were measured using a motion capture system with passive markers at 120-Hz sampling frequency. Landing and cutting maneuvers were administered in as natural way as possible. Results showed significant differences in landing and cutting maneuvers between groups in hip flexion, knee flexion and knee valgus angle. Results indicated that footballers have less extension of hip and knee joints than futsal players in landing maneuvers, which may be due to the higher requirement of jumping−landing maneuvers when playing football. In cutting maneuvers, footballers showed less hip and knee flexion than futsal players, whereas the knee valgus angle in cutting maneuvers was lower in futsal players. More information on the injury mechanisms of landing and cutting in football and futsal are needed to improve the design of injury prevention programs.