Anatomic correlates of reduced hip extension during walking in individuals with mild-moderate radiographic hip osteoarthritis

Gait compensations, pain, and functional performance during the six minute walk test in individuals with unilateral hip osteoarthritis

BACKGROUND

Individuals with unilateral hip osteoarthritis walk with kinematic and spatiotemporal compensations compared to healthy individuals. Our purpose was to determine associations between gait, pain, and functional performance during the six-minute walk test.

METHODS

Trunk and hip kinematics and spatiotemporal gait outcomes were recorded from individuals with unilateral hip osteoarthritis using inertial sensors (Xsens Technologies). Pain was collected prior to and at the end of the six-minute walk test. Paired t-tests were conducted to evaluate gait between limbs and between the first and final minutes of walking. Correlations were conducted between gait, pain, and six-minute walk test performance.

FINDINGS

Nineteen participants (8 females, age: 63 ± 5 yrs.

, BMI

29.0 ± 4.5 kg/m2) completed the study. Between-limb differences in hip flexion, hip extension, and trunk forward flexion peak angles were observed during the six-minute walk test (P < .05). Participants demonstrated an increase in trunk forward flexion of the osteoarthritis side (t = -2.34, P = .031) and a bilateral decrease in stride length (osteoarthritis limb: t = 2.98, P = .008, non- osteoarthritis limb: t = 3.17, P = .006) from the first to the final minute of walking. Greater pain was associated with greater osteoarthritis limb hip extension (first minute: r = -0.506, P = .027, final minute: r = -0.53, P = .020) and greater hip abduction (r = 0.46, P = .046) during the final minute of walking.

INTERPRETATIONS

Gait compensations increase throughout the six-minute walk test, and pain associates with hip kinematics during the six-minute walk test. Wearable technology may allow for more accurate clinical movement assessments.

Is hip capsule morphology associated with hip pain in patients without another structural correlate?

OBJECTIVE

The goals of this study were (i) to assess the association between hip capsule morphology and pain in patients without any other MRI abnormalities that would correlate with pain and (ii) to investigate whether hip capsule morphology in hip pain patients is different from that of controls.

METHODS

In this study, 76 adults with hip pain who did not show any structural abnormalities on MRI and 46 asymptomatic volunteers were included. Manual segmentation of the anterior and posterior hip capsules was performed. Total and mean anterior hip capsule area, posterior capsule area, anterior-to-posterior capsule area ratio, and medial-to-lateral area ratio in the anterior capsule were quantified. Differences between the pain and control groups were evaluated using logistic regression models.

RESULTS

Patients with hip pain showed a significantly lower anterior-to-posterior area ratio as compared with the control group (p = 0.002). The pain group's posterior hip capsule area was significantly larger than that of controls (p = 0.001). Additionally, the ratio between the medial and lateral sections of the anterior capsule was significantly lower in the pain group (p = 0.004).

CONCLUSIONS

Patients with hip pain are more likely to have thicker posterior capsules and a lower ratio of the anterior-to-posterior capsule area and thinner medial anterior capsules with a lower ratio of the medial-to-lateral anterior hip capsule compartment, compared with controls.

CLINICAL RELEVANCE STATEMENT

During MRI evaluations of patients with hip pain, morphology of the hip capsule should be assessed. This study aims to be a foundation for future analyses to identify thresholds distinguishing normal from abnormal hip capsule measurements.

KEY POINTS

• Even with modern image modalities such as MRI, one of the biggest challenges in handling hip pain patients is finding a structural link for their pain. • Hip capsule morphologies that correlated with hip pain showed a larger posterior hip capsule area and a lower anterior-to-posterior capsule area ratio, as well as a smaller medial anterior capsule area with a lower medial-to-lateral anterior hip capsule ratio. • The hip capsule morphology is correlated with hip pain in patients who do not show other morphology abnormalities in MRI and should get more attention in clinical practice.

The relationship of peak ankle dorsiflexion angle with lower extremity biomechanics during walking

PURPOSE

Abnormal lower limb movement patterns have been observed during walking in individuals with limited ankle dorsiflexion. The purpose of this study was to investigate the relationships of peak ankle dorsiflexion angle during the stance phase of walking with the lower extremity biomechanics at the corresponding moment and to determine a cutoff value of functional limited ankle dorsiflexion during walking.

METHODS

Kinematic and kinetic data of 70 healthy participants were measured during walking. Spearman's correlation coefficients were calculated to establish the association between peak ankle dorsiflexion and angle and moment of ankle, knee, and hip, ground reaction force, and pelvic movement at peak ankle dorsiflexion. All variables significantly related to peak ankle dorsiflexion were extracted as a common factor by factor analysis. Maximally selected Wilcoxon statistic was used to perform a cutoff value analysis.

RESULTS

Peak ankle dorsiflexion positively correlated with ankle plantar flexion moment (r = 0.432; p = 0.001), ankle external rotation moment (r = 0.251; p = 0.036), hip extension angle (r = 0.281; p = 0.018), hip flexion moment (r = 0.341; p = 0.004), pelvic ipsilateral rotation angle (r = 0.284; p = 0.017), and medial, anterior, and vertical ground reaction force (r = 0.324; p = 0.006, r = 0.543; p = 0.001, r = 0.322; p = 0.007), negatively correlated with knee external rotation angle (r = -0.394; p = 0.001) and hip adduction angle (r = -0.256; p = 0.032). The cutoff baseline value for all 70 participants was 9.03°.

CONCLUSIONS

There is a correlation between the peak ankle dorsiflexion angle and the lower extremity biomechanics during walking. If the peak ankle dorsiflexion angle is less than 9.03°, the lower limb movement pattern will change significantly.

Effects of hip osteoarthritis on lower body joint kinematics during locomotion tasks: a systematic review and meta-analysis

Introduction

Motion analysis can be used to gain information needed for disease diagnosis as well as for the design and evaluation of intervention strategies in patients with hip osteoarthritis (HOA). Thereby, joint kinematics might be of great interest due to their discriminative capacity and accessibility, especially with regard to the growing usage of wearable sensors for motion analysis. So far, no comprehensive literature review on lower limb joint kinematics of patients with HOA exists. Thus, the aim of this systematic review and meta-analysis was to synthesise existing literature on lower body joint kinematics of persons with HOA compared to those of healthy controls during locomotion tasks.

Methods

Three databases were searched for studies on pelvis, hip, knee and ankle kinematics in subjects with HOA compared to healthy controls during locomotion tasks. Standardised mean differences were calculated and pooled using a random-effects model. Where possible, subgroup analyses were conducted. Risk of bias was assessed with the Downs and Black checklist.

Results and Discussion

A total of 47 reports from 35 individual studies were included in this review. Most studies analysed walking and only a few studies analysed stair walking or turning while walking. Most group differences were found in ipsi- and contralateral three-dimensional hip and sagittal knee angles with reduced ranges of motion in HOA subjects. Differences between subjects with mild to moderate and severe HOA were found, with larger effects in severe HOA subjects. Additionally, stair walking and turning while walking might be promising extensions in clinical gait analysis due to their elevated requirements for joint mobility. Large between-study heterogeneity was observed, and future studies have to clarify the effects of OA severity, laterality, age, gender, study design and movement execution on lower limb joint kinematics.

Systematic Review Registration

PROSPERO (CRD42021238237).

Sagittal plane ankle kinetics are associated with dynamic hip range of motion and gait efficiency in women with hip osteoarthritis

Loss of sagittal plane hip range of motion (ROM) is a commonly reported walking gait impairment in people with hip osteoarthritis (OA). The purpose of this study was to evaluate whether sagittal plane hip ROM reduction and the resulting altered sagittal plane ankle kinetics during gait influence the energy cost of walking in people with hip OA. We evaluated 24 women with unilateral hip OA (60 ± 9.1 years; 29.4 ± 6.1 kg/m2 ). Sagittal plane hip ROM and peak ankle dorsiflexion moment were assessed by instrumented gait analysis. We also used a portable metabolic system to measure the energy cost of walking. Pearson correlations and regression analyses were performed to test our hypotheses. We found that greater involved limb sagittal plane hip ROM was associated with a larger ankle peak dorsiflexion moment at push-off during gait (R = 0.50, p = 0.01). Greater involved limb peak ankle dorsiflexion moment at push-off was associated with a lower oxygen consumption during gait (R = -0.51, p = 0.01). Involved limb peak ankle dorsiflexion moment at push-off predicted 26% of the variance in O2 cost. Statement of Clinical Significance: Sagittal plane hip ROM was associated with peak ankle dorsiflexion moment at push-off during gait in women with hip OA. Moreover, peak ankle dorsiflexion moment at push-off was associated with the energy cost of walking. Therefore, modifying sagittal plane hip ROM and peak ankle dorsiflexion moment could be a possible rehabilitation strategy to improve gait efficiency in women with hip OA.

Evaluating the contribution of fat infiltration in anterior gluteus minimus muscle to walking ability in female with unilateral hip osteoarthritis and candidates for total hip arthroplasty

BACKGROUND

The purpose of this study is to investigate the relationship between gait and fat infiltration in anterior and posterior gluteus minimus in the patients with hip osteoarthritis.

METHODS

Ninety-one female patients who were diagnosed as the unilateral hip osteoarthritis, classified into Kellgren-Lawrence global scoring system grades 3 or 4, and candidate for total hip arthroplasty were retrospectively reviewed. The horizontally cross-sectional regions of interest for the gluteus medius and anterior and posterior gluteus minimus were manually circumscribed in a single transaxial computed tomography image and muscle density of those regions were obtained. The gait was assessed as the step and speed with the 10-Meter Walk Test. The multiple regression analysis was used to compare the step and speed with age, height, range of motion in flexion, the muscle density of anterior gluteus minimus in the affected side, and that of gluteus medius muscle in both affected and unaffected sides.

FINDINGS

Multiple regression analysis for step revealed that the muscle density of anterior gluteus minimus in the affected side and height were the independent predictors for step (R² = 0.389, p < 0.001). That for speed identified the muscle density of anterior gluteus minimus in the affected side as the only factor determining speed (R² = 0.287, p < 0.001).

INTERPRETATION

The fatty infiltration of anterior gluteus minimus muscle in affected side can be a predictor for the gait in in female with unilateral hip osteoarthritis and candidates for total hip arthroplasty.

Effects of Hip Bracing on Gait Biomechanics, Pain and Function in Subjects With Mild to Moderate Hip Osteoarthritis

Hip Osteoarthritis (HOA) is a common joint disease with serious impact on the quality of life of the affected persons. Additionally, persons with HOA often show alterations in gait biomechanics. Developing effective conservative treatment strategies is of paramount importance, as joint replacement is only indicated for end-stage HOA. In contrast to knee osteoarthritis, little is known about the effectiveness of hip bracing for the management of HOA. Studies analysing mechanically unloading hip braces partly showed beneficial results. However, methodological limitations of these studies, such as small sample sizes or lack of control groups, limit the applicability of the results. Additionally, mechanically unloading braces might impose restrictions on motion and comfort and thus, might not be suitable for people with only mild or moderate symptoms. The aim of this study was to comprehensively quantify the effects of unilateral HOA as well as functional hip bracing on gait biomechanics, pain, proprioception and functional capacity in people with mild to moderate HOA. Hip and pelvis biomechanics during walking were analysed in 21 subjects with mild to moderate HOA under three bracing conditions: unbraced, immediately after brace application and after 1 week of brace usage. Additionally, pain, hip proprioception and functional capacity were assessed. A matched group of 21 healthy subjects was included as reference. Kinematic and kinetic data were collected using a 16-camera infrared motion capturing system and two force plates. Visual analogue scales, an angle reproduction test and a 6-min walking test were applied to measure pain, hip proprioception and functional capacity, respectively. Subjects with HOA walked slower, with reduced step length, sagittal hip range of motion and peak extension angle and had a reduced functional capacity. After 1 week of brace application step length, walking speed and functional capacity were significantly increased. Additionally, pain perception was significantly lower in the intervention period. These results encourage the application of functional hip braces in the management of mild to moderate HOA. However, as key parameters of HOA gait such as a reduced peak extension angle remained unchanged, the underlying mechanisms remain partly unclear and have to be considered in the future.

A Randomized, Open-Label, Single-Dose Study to Assess Safety and Systemic Exposure of Triamcinolone Acetonide Extended-Release in Patients With Hip Osteoarthritis

Introduction

Intra-articular (IA) corticosteroids, including triamcinolone acetonide (TA), are a recommended treatment for hip osteoarthritis. We compared the safety and systemic exposure of TA extended-release (TA-ER) versus TA crystalline suspension (TAcs) in patients with hip osteoarthritis.

Methods

In this phase 2, randomized, multicenter, open-label, single-dose study (NCT03382262), patients with hip osteoarthritis were randomly assigned 1:1 to receive single IA injections of TA-ER 32 mg or TAcs 40 mg. Safety assessments included treatment-emergent adverse events (TEAEs). Blood samples were collected for pharmacokinetic (PK) analysis up to day 85. PK parameters included area under the concentration–time curve, total body drug clearance, maximum concentration (C_max), mean residence time, half-life, and time to maximum concentration.

Results

Of 30 patients (TA-ER: n = 15; TAcs: n = 15) randomized and included in the Safety Population, 25 patients were evaluated in the PK Population. TEAEs were reported in four of 15 (26.7%) patients who received TA-ER and in seven of 15 (46.7%) patients who received TAcs. The most common TEAEs included arthralgia and headache. All TEAEs were of grade 1 or 2 in severity. TA-ER produced substantially lower peak plasma TA concentrations compared with TAcs (C_max geometric mean: 890.4 vs. 5549.4 pg/ml), and these were less variable with TA-ER versus TAcs. Similarly, overall TA systemic exposure was substantially lower for TA-ER versus TAcs, with gradual elimination from systemic circulation through day 85.

Conclusions

Following a single IA injection in the hip, TA-ER was generally well tolerated, with a safety profile comparable to that of TAcs. Systemic TA exposure was markedly lower in TA-ER-treated patients, consistent with the PK profile observed in knee osteoarthritis.

Clinicaltrials.gov identifier: NCT03382262.

Hip joint kinematics and segment coordination variability according to pain and structural disease severity in hip osteoarthritis

This study aimed to evaluate hip joint kinematic variability and segment coordination variability during walking according to pain and radiographic disease severity in people with hip osteoarthritis. Fifty-five participants with hip osteoarthritis had pain severity assessed during walking using an item on the Western Ontario and McMasters Universities Osteoarthritis Index (no pain = 10; mild pain = 28; moderate pain = 17). Radiographic disease severity was graded by Kellgren and Lawrence scale (KL2 = 29; KL3 = 21; KL4 = 5). Hip kinematics variability was estimated as the curve coefficient of variation. Vector coding was used to calculate coordination variability for select joint couplings. One-way analysis of variances with planned adjusted post hoc comparisons were used to compare hip kinematics variability and coordination variability of select segment couplings (pelvis sagittal vs thigh sagittal; pelvis frontal vs thigh frontal; pelvis transverse vs thigh transverse; thigh sagittal vs shank sagittal; thigh frontal vs shank sagittal; thigh transverse vs shank sagittal) according to pain and radiographic disease severity. No main effect of pain severity was observed for sagittal or transverse plane hip kinematic variability (P ≥ .266), and although there was a main effect for frontal plane hip kinematic variability (P = .035), there were no significant differences when comparing between levels of pain severity (P > .006). There was no main effect of radiographic disease severity on hip kinematic variability in the sagittal (P = .539) or frontal (P = .307) plane. No significant differences in coordination of variability of segment couplings were observed (all P ≥ .229). Movement variability as assessed in this study did not differ according to pain severity during walking or radiographic disease severity.

Extracting Voxel-Based Cartilage Relaxometry Features in Hip Osteoarthritis Subjects Using Principal Component Analysis

BACKGROUND

MRI-based relaxation time measurements provide quantitative assessment of cartilage biochemistry. Identifying distinctive relaxometry features in hip osteoarthritis (OA) might provide important information on regional disease variability.

PURPOSE

First, to incorporate fully automatic voxel-based relaxometry (VBR) with principal component analysis (PCA) to extract distinctive relaxometry features in subjects with radiographic hip OA and nondiseased controls. Second, to use the identified features to further distinguish subjects with cartilage compositional abnormalities.

STUDY TYPE

Cross-sectional.

SUBJECTS

Thirty-three subjects with radiographic hip OA (20 males; age, 50.2 ± 13.3 years) and 55 controls participated (28 males; 41.3 ± 12.0 years).

SEQUENCE

A 3.0T scanner using 3D SPGR, combined T_1ρ /T₂ , and fast spin echo sequences.

ASSESSMENT

Pelvic radiographs, patients' self-reported symptoms, physical function, and cartilage morphology were analyzed. Cartilage relaxation times were quantified using traditional regions of interest and VBR approaches. PCA was performed on VBR data to identify distinctive relaxometry features, and were subsequently used to identify a subgroup of subjects from the controls that exhibited compositional abnormalities.

STATISTICAL TESTS

Chi-square and independent t-tests were used to compare group characteristics. Logistic regression models were used to identify the possible principal components (PCs) that were able to predict OA vs. control classification.

RESULTS

In T_1ρ assessment, OA subjects demonstrated higher T_1ρ values in the posterior hip region and deep cartilage layer when compared with controls (P = 0.012 and 0.001, respectively). In T₂ assessment, OA subjects exhibited higher T₂ values in the posterior hip region (P < 0.001). Based on the PC score classification, 16 subjects without radiographic evidence of OA demonstrated relaxometry patterns similar to OA subjects, and exhibited worse physical function (P = 0.003) and cartilage lesions (P = 0.009-0.032) when compared with the remaining controls.

DATA CONCLUSION

The study identified distinctive cartilage relaxometry features that were able to discriminate subjects with and without radiographic hip OA effectively.

LEVEL OF EVIDENCE

1 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:1708-1719.

Patients with Symptomatic Hip Osteoarthritis Have Altered Kinematics during Stair Ambulation

BACKGROUND

Osteoarthritis (OA) is a degenerative joint disease. Understanding contributing factors to slowing or stopping disease progression is crucial. There has been no research describing lower extremity kinematics of the hip, knee, and ankle during stair ambulation in individuals with hip OA.

OBJECTIVE

To explore the differences in lower extremity kinematics between participants with clinical and morphological findings of hip OA and controls.

DESIGN

A cross-sectional study.

SETTING

Clinical research laboratory.

PARTICIPANTS

Participants with radiographic and symptomatic signs of hip OA (n = 42) and healthy controls (n = 30) were enrolled.

INTERVENTIONS

Participants underwent hip magnetic resonance imaging (MRI). The Scoring Hip Osteoarthritis with MRI (SHOMRI) method was used to assess cartilage abnormalities. Self-reported measures of hip pain and function were obtained using the Hip Disability and Osteoarthritis Outcome Score (HOOS). Participants were assigned into a symptomatic hip osteoarthritis group (HOA) with SHOMRI>0 and HOOS≤80, and a control group (CG) with SHOMRI = 0 and HOOS>90. Patients underwent 3D motion analysis during stair ascent/descent at self-selected speed.

MAIN OUTCOME MEASURES

The primary outcome measurements were peak hip, knee, and ankle kinematics. General Estimation Equations were used to compare kinematics between groups (P ≤ .05).

RESULTS

The HOA group ascended stairs with a more internally rotated hip (CG = 1.77 ± 6.3; HOA = 4.97 ± 4.2; P = .02), more abducted hip (CG = -5 ± 2.7, HOA = -3.5 ± 3; P = .02), and a more externally rotated knee (CG = -8.02 ± 3; HOA = -10.63 ± 6.3; P = .02) and ankle (CG = -11.8 ± 6.1; HOA = -16.3 ± 5.6; P = .01). Similarly, HOA participants descended stairs with a more extended knee (CG = -15.5 ± 4.9; HOA = -12 ± 4.9; P = .01), and more externally rotated knee (CG = -10.1 ± 4.4; HOA = -13.1 ± 6.6; P = .04) and ankle (CG = -13.5 ± 5.3; HOA = -17.9 ± 5.5; P = .002).

CONCLUSION

Participants with hip OA-related morphology and symptoms ambulate stairs utilizing abnormal lower extremity mechanics.

Is the Pelvis-Thorax Coordination a Valuable Outcome Instrument to Assess Patients With Hip Osteoarthritis?

Objective: The evaluation of the disease severity in hip osteoarthritis (OA) patients being currently based on subjective instruments. It would be of interest to develop more objective instruments, for example based on gait analysis. The aims of this study were to explore if pelvis-thorax coordination parameters could be valuable instrument outcomes to achieve this evaluation by assessing their reliability, discriminant capacity and responsiveness.

Methods: Three groups of subjects; healthy, hip OA patients with severe disease (defined as indication to surgery), hip OA patients with less severe disease (no indication to surgery) were included. Hip OA patients with severe disease were evaluated before and 6 months after surgery. Subjects had to perform a gait analysis at comfortable speed, and pelvis-thorax coordination was evaluated. The correlations with clinical and structural parameters, as well as reliability, discriminant capacities and responsiveness, were assessed.

Results: The pelvis-thorax coordination in the coronal plane during walking was correlated to clinical and to structural severity in hip OA patients (R² = 0.13). The coronal plane coordination allowed to discriminate healthy subjects from all hip OA patients (sensibility = 0.86; specificity = 0.59). Moreover, when comparing OA patients only, coronal plane coordination allows to discriminate patients with indication of surgery from those with no indication of surgery (sensibility = 0.72; specificity = 0.72). Moreover, the pelvis-thorax coordination demonstrated an excellent reliability and a good responsiveness.

Conclusion: Changes in the pelvis-thorax coordination might refer to different mechanisms, from analgesia to motor control plasticity, and might be a possible explanation for the weak correlation between structure and symptoms in hip OA patients. Moreover, such parameter might be used as an objective outcome in hip OA clinical trials.

Clinical Trials Registration:www.ClinicalTrials.gov, identifier: NCT02042586 and NCT01907503.

Short term outcomes of hip arthroscopy on hip joint mechanics and cartilage health in patients with femoroacetabular impingement syndrome

BACKGROUND

Femoroacetabular acetabular impingement syndrome consists of abnormal hip joint morphology resulting in painful hip joint impingement. Hip arthroscopy corrects the abnormal morphology and reduces clinical symptoms associated with femoroacetabular impingement syndrome yet the effects of hip arthroscopy on gait mechanics and cartilage health are not well understood.

METHODS

Ten femoroacetabular impingement syndrome patients and 10 matched asymptomatic controls underwent gait analysis consisting of three-dimensional hip joint kinematics and kinetics. Femoroacetabular impingement syndrome patients underwent gait analysis and quantitative magnetic resonance imaging of the surgical hip joint before and seven months post-surgery. Patient reported outcomes were obtained from all study participants and were used to quantify hip joint pain, function and quality of life.

FINDINGS

Prior to surgery, femoroacetabular impingement syndrome patients demonstrated hip joint kinematics or kinetics as the control group. After surgery, femoroacetabular impingement syndrome patients exhibited improved patient reported outcomes, similar hip joint kinematic patterns, increased hip flexion and decreased hip extension moment impulses within the surgical limb. The femoroacetabular impingement syndrome patients that ambulated with increased HFMI post-surgery demonstrated a decrease in femoral cartilage T1ρ and T2 values.

INTERPRETATION

Femoroacetabular impingement syndrome patients exhibited improved clinical symptoms yet ambulated with altered sagittal plane hip joint loading after hip arthroscopy. Increased hip flexion moment impulse post-surgery was associated with improved cartilage health within the surgical limb. These study findings suggest that sagittal plane hip joint loading at short-term follow-up after hip arthroscopy is associated with cartilage health and may be an important biomechanical parameter in post-operative rehabilitation programs.

Abnormal Joint Loading During Gait in Persons With Hip Osteoarthritis Is Associated With Symptoms and Cartilage Lesions

BACKGROUND

Hip joint loading in persons with hip osteoarthritis (OA) is not well studied, and its associations with symptoms and lesions are unknown.

OBJECTIVES

To determine whether hip joint loading differs between people with and without radiographic hip OA, and to identify its associations with patients' symptoms and cartilage morphology.

METHODS

Forty-eight patients (28 male; mean ± SD age, 56.0 ± 12.2 years) with hip OA and 95 controls (40 male; age, 43.2 ± 13.6 years) participated in this cross-sectional analysis. Pelvic radiographs, questionnaires, magnetic resonance imaging (MRI), and gait analysis were conducted. The Hip disability and Osteoarthritis Outcome Score (HOOS) was used to assess symptoms. Cartilage morphology was graded on MRI scans using the Scoring Hip Osteoarthritis with Magnetic Resonance Imaging (SHOMRI) system. Biomechanical variables included peak external hip joint moment (Newton meters per kilogram) and moment impulses (Newton meters times milliseconds per kilogram) in all planes. Generalized estimating equations were used to compare the biomechanical characteristics between groups. In the patients with OA, associations of moment impulses with HOOS and SHOMRI scores were assessed with partial correlations.

RESULTS

The OA group exhibited higher peak external hip flexion and adduction moments (P<.001) and higher hip flexion, adduction, and external rotation moment impulses (P = .001-.039). Increased hip flexion moment impulses were correlated with worse HOOS subscale scores (r = -0.361 to -0.424, P<.05) and worse femoral SHOMRI grades (ρ = 0.256-0.315, P<.05). Increased hip external rotation moment impulses were correlated with worse femoral SHOMRI grades (ρ = 0.283-0.372, P<.05).

CONCLUSION

Persons with hip OA exhibited abnormally high hip joint loads during walking, and high loads were associated with worse self-reported symptoms and cartilage morphology. J Orthop Sports Phys Ther 2019;49(12):917-924. Epub 14 Oct 2019. doi:10.2519/jospt.2019.8945.

Descriptions of movement experiences in the Body Awareness Rating Scale - Movement Quality and Experience evaluation. A qualitative study of patients diagnosed with hip osteoarthritis

Background: Patients' access to movement experiences is implemented in the evaluation tool Body Awareness Rating Scale - Movement Quality and Experience, with its two intertwined parts: 1) the physiotherapist's observations of movement quality; and 2) the patient's descriptions of immediate movement experiences.Objective: To study movement experiences and reflections described by patients diagnosed with hip osteoarthritis when guided to explore simple daily-life movements in this particular evaluation context.Design: An explorative qualitative study with open-ended questions following each of the 12 movements integrated into the evaluation.Methods: 35 participants diagnosed with hip osteoarthritis were included; 28 women and 7 men, aged 23-78 years. Their descriptions were audiotaped, transcribed verbatim and analyzed in accordance with qualitative content analysis.Results: The patients described experiences of a dynamic adaptation of movement strategies based on sensations from the moving body. Two interrelated categories of movement awareness were identified: 1) Experienced movement challenges, including three sub-categories; a) Lack of contact, b) Movement changed by symptoms, and c) Compensational movement habits, and 2) Movement components promoting well-being, including three sub-categories; a) Integrating balance, breathing and awareness into movement, b) Small, simple, soft and safe movements, and c) A taste of own movement resources for daily life.Conclusions: The Body Awareness Rating Scale - Movement Quality and Experience provides a platform for patients to become aware of and describe their movement habits and resources in own words, intertwined with the physiotherapist movement observations. Derived descriptions reflect a patient perspective to be implemented in therapy.

Gait- and Posture-Related Factors Associated With Changes in Hip Pain and Physical Function in Patients With Secondary Hip Osteoarthritis: A Prospective Cohort Study

OBJECTIVE

To identify gait- and posture-related factors associated with changes in hip pain and physical function in patients with hip osteoarthritis (OA).

DESIGN

Prospective cohort study.

SETTING

Clinical biomechanics laboratory of a university.

PARTICIPANTS

Consecutive sampling of female patients with mild-to-moderate secondary hip OA (N=30).

MAIN OUTCOME MEASURES

Hip pain (visual analog scale) and physical function (physical component summary of the Medical Outcomes Study 36-Item Short-Form Health Survey) were measured at baseline and 12 months later. With changes in hip pain and physical function as dependent variables, linear regression analyses were performed with gait- and posture-related factors as independent variables with and without adjustment for age, joint space width, and hip pain or physical function at baseline. Posture-related factors included angles of thoracic kyphosis, lumbar lordosis, sacral inclination, spinal inclination, and spinal mobility. Gait-related factors were walking speed, steps per day, joint angles, external hip joint moment impulses, and daily cumulative hip moments.

RESULTS

Multiple linear regression analyses showed that limited hip extension (adjusted standardized B coefficient [95% confidence interval]: -0.52 [-0.88 to -0.17]) and limited external rotation angles (-0.51 [-0.85 to -0.18]) during walking were associated with the worsening of hip pain. An increased thoracic kyphosis (-0.54 [-0.99 to -0.09]), less sacral anterior tilt (0.40 [0.01-0.79]), reduced thoracic spine mobility (0.59 [0.23-0.94]), less steps per day (0.53 [0.13-0.92]), and a slower walking speed (0.45 [0.04-0.86]) were associated with deterioration in physical function.

CONCLUSIONS

Gait- and posture-related factors should be considered when assessing risk and designing preventive interventions for the clinical progression of secondary hip OA.

Hip joint moments during walking in people with hip osteoarthritis: a systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis investigated surrogate measures of hip joint loading during walking in people with hip osteoarthritis (OA).

METHODS

Five databases were searched up to January 14^th, 2018. Studies that measured hip joint moments in the frontal or sagittal plane during walking in people with hip OA and used either a healthy control group or the unaffected leg to compare hip joint moments were included. Standardised mean differences (SMD) in sagittal and frontal plane moments were pooled as appropriate, using a random effect approach. Methodological quality was assessed using the Downs and Black checklist.

RESULTS

Thirteen studies with 1,141 participants were eligible and suitable for meta-analyses. Overall, people with hip OA had lower sagittal (SMD -0.55 (95% confidence interval (CI) -1.00 to -0.10) and frontal plane moments (SMD -0.63 (95% CI -0.92, -0.34) compared to controls. However, substantial heterogeneity was observed (I² ≤ 89%). Results by disease stage suggest that people with end-stage hip OA have lower sagittal (SMD -0.96; -1.30, -0.61; I² = 69%) and frontal (SMD -1.17; 95% CI -1.71, -0.64; I² = 85%) plane moments compared to controls. People with less severe hip OA than end-stage disease have comparable sagittal (SMD 0.37; 95% CI -0.17, 0.90; I² = 69%) and frontal (SMD -0.24; 95% CI -0.76, 0.27; I² = 51%) plane moments compared to controls.

CONCLUSION

Hip joint loading may be dependent on disease stage. People with end-stage hip OA under-loaded compared to controls, while those who were not awaiting hip joint replacement had comparable hip joint loads to controls.

Balance performance in older adults with hip osteoarthritis: A systematic review

BACKGROUND

The hip is one of the most common joints affected by osteoarthritis (OA) and it has been identified as a key risk factors for falls. Physical impairments associated with OA, such as joint pain, muscle weakness, joint stiffness and sensory dysfunction, can all negatively affect balance and increase risk of falling.

QUESTION

Is balance performance altered in older adults with hip osteoarthritis? To determine whether static, dynamic, reactive or functional balance performance is altered in older people with hip osteoarthritis.

METHODS

Quantitative measures of postural control, including clinical and lab-based assessment of static, dynamic, reactive and/or functional balance performance, compared with a healthy control group or to the asymptomatic limb.

RESULTS

A total of 5407 articles were identified and 14 papers were included (10 with standardised mean different (SMD) data, four without SMD data). Based on data from single studies, there were medium/large effects for increased medio-lateral displacement when standing with eyes open, increased anterior-posterior and total sway path length when standing with eyes closed, greater overall instability when standing on an unstable surface, and increased displacement toward the stance leg in a lateral step in hip OA compared with controls.

CONCLUSION

Balance impairments were identified in some measures, limiting the conclusions as to whether balance deficits are a problem in hip OA. Inconsistent findings suggest that balance may not be a primary contributor to increased falls risk in older adults with hip OA. Other factors, such as musculoskeletal deficits, may contribute to higher falls rate in this population.

Different reliability of instrumented gait analysis between patients with unilateral hip osteoarthritis, unilateral hip prosthesis and healthy controls

BACKGROUND

The gait pattern varies within the population and between patient groups with different musculoskeletal diseases. It also varies over time due to various reasons. Three-dimensional gait analysis (3DGA) is frequently used to measure these changes, but the precision of this methodology may vary.

METHODS

We primarily aimed to study the repeatability of hip motion measurements in patients with unilateral osteoarthritis (OA), patients with unilateral total hip arthroplasty (THA) and healthy controls. A secondary aim was to delineate any differences in hip motion during walking between these groups. Ten males and 10 females in each group were recruited. All patients underwent gait assessments using 3DGA recorded by 2 examiners. Data was analysed with comparison of variance and linear regression.

RESULTS

The variability of the extension-flexion recordings was smallest in healthy controls (SD < 7.7°), increased in patients with THA (SD < 11.1°) and was most pronounced in the OA patients (SD < 12.2°). The degree of hip extension-flexion turned out to be the variable that most effectively could separate the controls from the 2 patient groups and the patient groups from each other. One to 2 years after THA the gait pattern was improved but still differed comparing a group of THA from a group of healthy controls.

CONCLUSIONS

Patients with hip osteoarthritis showed the poorest repeatability between gait recordings collected by different examiners, as compared to patients operated with a THA and healthy controls. The walking pattern after THA still differed from healthy controls 1-2 years after the operation.

Sagittal plane walking patterns are related to MRI changes over 18-months in people with and without mild-moderate hip osteoarthritis

The purpose was to evaluate the association of sagittal plane gait mechanics with MRI changes in the hip joint over 18-months. Subjects with and without radiographic hip OA (n = 57) underwent MRI at baseline and 18 months for grading of cartilage lesions, bone marrow lesions (BML), cysts, and labral tears. 3D gait analyses at baseline were used for sagittal plane hip kinematics and kinetics during the stance phase. Subjects were classified as progressors or non-progressors based on increase in any MRI OA parameter. Multivariate ANOVA were used for differences in sagittal gait parameters between progressors and non-progressors at baseline while adjusting for age. Logistic regression was used to estimate the probability of being classified as a progressor or non-progressor with increasing hip flexion while adjusting for age, BMI, sex, and presence of radiographic hip OA. Of the 57, 35 were classified as non-progressors and 22 were classified as progressors. At baseline, the progressors walked with 4.5° greater hip flexion during early stance (p = 0.021) and 3.5° lesser hip extension in late stance that was nearly significant (p = 0.059). Walking with greater hip flexion at baseline was associated with a greater risk of increase in MRI defined structural changes in the hip joint (Odds Ratio = 1.1, p = 0.038). Greater hip flexion during walking was associated with a risk of structural progression of hip OA. The results may guide future interventions to alter the walking patterns and slow structural hip OA progression.© 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1472-1477, 2018.

Acetabular labrum of hip joint in osteoarthritis: A qualitative original study and short review of the literature

PURPOSE

Histological architecture of normal acetabular labrum regarding free nerve endings (FNEs) and mechanoreceptors (MRs) has been satisfactorily described in the literature. However, the presence of FNEs and MRs in acetabular labrum of hip joint has been analyzed only once in patients with osteoarthritis (OA). Aim of this article is to report histological distribution pattern of FNEs and MRs in acetabular labrum of patients with severe OA, at the same time conducting a comparison with normal acetabular labrum described in the literature.

METHODS

Seven patients with severe hip OA were enrolled in this study. Patient selection was assisted by the utilization of specific clinical scales delineated by the American College of Rheumatology. After successful total hip arthroplasty, tissue samples of acetabular labra of seven patients were histologically processed and stained with the gold standard chloride method, which was subsequently examined under a compound microscope.

RESULTS

FNEs and MRs constituted the major histological structures. Identified MRs included Pacini corpuscles, Ruffini corpuscles, and Golgi-Mazzoni corpuscles. The presence of FNEs was predominant in the middle part of the acetabular labrum, featuring a remarkable decrease in peripheral parts. In contrast, MRs were detected basically in peripheral parts and less in the middle part.

CONCLUSIONS

Differentiation of the distribution pattern of MRs and FNEs in acetabular labrum of hip joint is remarkable between normal patients and patients with severe OA. The abundance of FNEs in the middle part of the pathologic labrum is mainly responsible for the observed discrimination. A "conversion" of MRs to FNEs may occur during OA progression, modulating therefore this pattern as well as the upcoming clinical manifestations.

Abnormal loading of the hip and knee joints in unilateral hip osteoarthritis persists two years after total hip replacement

A total hip replacement (THR) is a common and routine procedure to reduce pain and restore normal activity. Gait analysis can provide insights into functional characteristics and dynamic joint loading situation not identifiable by clinical examination or static radiographic measures. The present prospective longitudinal study tested whether 2 years after surgery a THR would restore dynamic loading of the knee and hip joints in the frontal plane to normal. Instrumented gait analysis was performed shortly before surgery and approximately 2 years after THR on 15 unilateral hip osteoarthritis (OA) patients. 15 asymptomatic matched individuals were recruited as healthy controls. Results showed that abnormal joint loading persisted 2 years after THR. The 2nd external knee adduction moment in terminal stance in the affected (-34%, p = 0.002, d = 1.22) and non-affected limb (-25%, p = 0.035, d = 0.81) was lower compared to controls and thus indicated a shift in the knee joint load distribution from medial to lateral. A correlation analysis revealed that a smaller hip range of motion explained 46% of 2nd knee adduction moment alterations. In contrast, the 2nd external hip adduction moment in terminal stance was postoperatively higher in the affected (+22%, p = 0.007, d = 1.04) and non-affected limb (+22%, p = 0.005, d = 1.05). Here, 51% of 2nd hip adduction moment alterations can be explained with a greater hip adduction angle. Patients with a THR may therefore be at higher risk for abnormal joint loading and thus for the development of OA in other joints of the lower extremities. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Gluteal tendinopathy and hip osteoarthritis: Different pathologies, different hip biomechanics

BACKGROUND

Gluteal tendinopathy (GT) and hip osteoarthritis (OA) are the most common causes of hip pain and associated disability in older adults. Pain and altered walking biomechanics are common to both conditions. This study aimed to compare three-dimensional walking biomechanics between individuals with unilateral, symptomatic GT and HOA.

METHODS

Sixty individuals with symptomatic unilateral GT confirmed by magnetic-resonance-imaging and 73 individuals with symptomatic unilateral HOA (Kellgren-Lawrence Grade ≥ 2) underwent three-dimensional gait analysis. Maximum and minimum values of the external sagittal hip moment, the first peak, second peak and mid-stance minimum of the hip adduction moment (HAM), sagittal plane hip excursion and hip joint angles, pelvic obliquity and trunk lean, at the three HAM time points during stance phase of walking were compared between groups.

RESULTS

Compared to individuals with HOA, those with GT exhibited a greater hip peak extension moment (P < 0.001) and greater HAM throughout the stance phase of walking (P = 0.01-P < 0.001), greater hip adduction (P < 0.001) and internal rotation (P < 0.01-P < 0.001) angles and lower hip flexion angles and excursion (P = 0.02 - P < 0.001). Individuals with HOA exhibited a greater forward trunk lean (P ≤ 0.001) throughout stance, and greater ipsilateral trunk lean in the frontal plane (P < 0.001) than those with GT.

CONCLUSION

Despite presence of pain in both conditions, hip kinematics and kinetics differ between individuals with symptomatic unilateral GT and those with symptomatic unilateral HOA. These condition-specific impairments may be targets for optimization of management of HOA and GT.

Study of the interactions between proximal femur 3d bone shape, cartilage health, and biomechanics in patients with hip Osteoarthritis

In this study quantitative MRI and gait analysis were used to investigate the relationships between proximal femur 3D bone shape, cartilage morphology, cartilage biochemical composition, and joint biomechanics in subject with hip Osteoarthritis (OA). Eighty subjects underwent unilateral hip MR-imaging: T1ρ and T2 relaxation times were extracted through voxel based relaxometry and bone shape was assessed with 3D MRI-based statistical shape modeling. In addition, 3D gait analysis was performed in seventy-six of the studied subjects. Associations between shape, cartilage lesion presence, severity, and cartilage T1ρ and T2 were analyzed with linear regression and statistical parametric mapping. An ad hoc analysis was performed to investigate biomechanics and shape associations. Our results showed that subjects with a higher neck shaft angle in the coronal plane (higher mode 1, coxa valga), thicker femoral neck and a less spherical femoral head (higher mode 5, pistol grip) exhibited more severe acetabular and femoral cartilage abnormalities, showing different interactions with demographics factors. Subjects with coxa valga also demonstrated a prolongation of T1ρ and T2. Subjects with pistol grip deformity exhibited reduced hip internal rotation angles and subjects with coxa valga exhibited higher peak hip adduction moment and moment impulse. The results of this study establish a clear relationship between 3D proximal femur shape variations and markers of hip joint degeneration-morphological, compositional, well as insight on the possible interactions with demographics and biomechanics, suggesting that 3D MRI-based bone shape maybe a promising biomarker of early hip joint degeneration. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:330-341, 2018.

Positive outcomes following gait therapy intervention for hip osteoarthritis: A longitudinal study

Footwear-generated biomechanical manipulation of lower-limb joints was shown to beneficially impact gait and quality of life in knee osteoarthritis patients, but has not been tested in hip osteoarthritis patients. We examined a customized gait treatment program using a biomechanical device shown in previous investigations to be capable of manipulating hip biomechanics via foot center of pressure (COP) modulation. The objective of this study was to assess the treatment program for hip osteoarthritis patients, enrolled in a 1-year prospective investigation, by means of objective gait and spatiotemporal parameters, and subjective quality of life measures. Gait analysis and completion of questionnaires were performed at the start of the treatment (baseline), and after 3, 6, and 12 months. Outcome parameters were evaluated over time using linear mixed effects models, and association between improvement in quality of life measures and change in objective outcomes was tested using mixed effect linear regression models. Quality of life measures improved compared to baseline, accompanied by increased gait speed and cadence. Sagittal-plane hip joint kinetics, kinematics, and spatiotemporal parameters changed throughout the study compared to baseline, in a manner suggesting improvement of gait. The most substantial improvement occurred within 3 months after treatment initiation, after which improvement approximately plateaued, but was sustained at 12 months. Speed and cadence, as well as several sagittal-plane gait parameters, were significant predictors of improvement in quality of life.

CLINICAL SIGNIFICANCE

Evidence suggests that a biomechanical gait therapy program improves subjective and objective outcomes measures and is a valid treatment option for hip osteoarthritis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2222-2232, 2017.

Sex-specific hip osteoarthritis-associated gait abnormalities: Alterations in dynamic hip abductor function differ in men and women

BACKGROUND

Hip osteoarthritis results in abnormal gait mechanics, but it is not known whether abnormalities are the same in men and women. The hypothesis tested was that gait abnormalities are different in men and women with hip osteoarthritis vs. sex-specific asymptomatic groups.

METHODS

150 subjects with mild through severe radiographic hip osteoarthritis and 159 asymptomatic subjects were identified from an Institutional Review Board-approved motion analysis data repository. Sagittal plane hip range of motion and peak external moments about the hip, in all three planes, averaged from normal speed walking trials, were compared for men and women, with and without hip osteoarthritis using analysis of variance.

FINDINGS

There were significant sex by group interactions for the external peak hip adduction and external rotation moments (P=0.009-0.045). Although asymptomatic women had peak adduction and external rotation moments that were respectively 12% higher and 23% lower than asymptomatic men (P=0.026-0.037), these variables did not differ between men and women with hip osteoarthritis (P≥0.684). The osteoarthritis vs. asymptomatic group difference in the peak hip adduction moment was 45% larger in women than in men. The osteoarthritis vs. asymptomatic group difference in the peak hip external rotation moment was 55% larger for men than for women (P<0.001). Sex did not influence the association between radiographic severity and gait variables.

INTERPRETATION

Normal sex differences in gait were not seen in hip osteoarthritis. Sex-specific adaptations may reflect different aspects of hip abductor function. Men and women with hip osteoarthritis may require different interventions to improve function.

Hip biomechanics during stair ascent and descent in people with and without hip osteoarthritis

Hip osteoarthritis (OA) is often associated with pain and impaired function. Understanding biomechanical alterations in patients with hip OA during challenging activities such as stair use is important to inform treatments. The aim of this study was to determine whether kinematics and kinetics during stair ambulation differed between people with hip OA and healthy controls. Fifteen participants with symptomatic and radiographic hip OA and 15 asymptomatic healthy controls underwent 3-D motion analysis during stair ascent and descent. Trunk, pelvis, and hip kinematics as well as hip kinetics were evaluated. Analyses were performed unadjusted and adjusted for speed and leg length. In both the unadjusted and adjusted analyses, participants with hip OA ascended stairs with less hip range of motion in all three planes and a lower peak external rotation moment compared to controls. In the unadjusted analysis, hip OA participants descended stairs with greater ipsilateral trunk lean, less sagittal plane range of motion, lower peak extension moment, lower peak external rotation moment, and greater hip adduction moment impulse compared to controls. In the adjusted results, peak internal rotation moment and hip adduction moment impulse were greater in hip OA participants compared to controls. Findings show that individuals with hip OA display limited range of hip joint movement, particularly during stair ascent, and overall indicate the use of strategies (e.g., trunk lean; lower peak external rotation moment; higher adduction moment impulse) that implicate altered hip abductor function. Future research is required to further understand the implications of these findings on hip OA. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1505-1514, 2017.

Roussouly's sagittal spino-pelvic morphotypes as determinants of gait in asymptomatic adult subjects

Sagittal alignment is known to greatly vary between asymptomatic adult subjects; however, there are no studies on the possible effect of these differences on gait. The aim of this study is to investigate whether asymptomatic adults with different Roussouly sagittal alignment morphotypes walk differently. Ninety-one asymptomatic young adults (46M & 45W), aged 21.6±2.2years underwent 3D gait analysis and full body biplanar X-rays with three-dimensional (3D) reconstructions of their spines and pelvises and generation of sagittal alignment parameters. Subjects were divided according to Roussouly's sagittal alignment classification. Sagittal alignment and kinematic parameters were compared between Roussouly types. 17 subjects were classified as type 2, 47 as type 3, 26 as type 4 but only 1 as type 1. Type 2 subjects had significantly more mean pelvic retroversion (less mean pelvic tilt) during gait compared to type 3 and 4 subjects (type 2: 8.2°; type 3:11.2°, type 4: 11.3°) and significantly larger ROM pelvic obliquity compared to type 4 subjects (type 2: 11.0°; type 4: 9.1°). Type 2 subjects also had significantly larger maximal hip extension during stance compared to subjects of types 3 and 4 (type 2: -11.9°; type 3: -8.8°; type 4: -7.9°) and a larger ROM of ankle plantar/dorsiflexion compared to type 4 subjects (type 2: 31.1°; type 4: 27.9°). Subjects with type 2 sagittal alignment were shown to have a gait pattern involving both increased hip extension and pelvic retroversion which could predispose to posterior femoroacetabular impingement and consequently osteoarthritis.

Hip joint mechanics during walking in individuals with mild-to-moderate hip osteoarthritis

The purpose of this case-control study was to characterise hip joint kinematics and moments during gait in people with mild-to-moderate hip osteoarthritis (OA). Eligible participants were allocated to the hip OA group (n=27) or the age-matched control group (n=26) based on radiographic and symptomatically defined inclusion criteria. Participants walked barefoot along a 10-m walkway at their self-selected gait speed. Trajectories of 43 markers attached to the trunk, pelvis, upper and lower limbs were recorded using a 12-camera motion capture system. Ground reaction force data were simultaneously collected. Individuals in the hip OA group had a 10% higher body mass, 13% slower self-selected walking speed, 10% shorter step length, 2% and 9% longer relative stance and double support duration (% stride) respectively, 41% lower sagittal plane hip range of motion, and 28% and 45% lower peak sagittal and transverse plane hip joint moments respectively during gait compared to controls (p<0.05). The finding that individuals with mild-to-moderate hip OA experienced less net hip joint loading over a reduced range of hip motion for a longer proportion of the gait cycle when walking at their preferred gait speed suggest that the mechanics of the hip joint are altered in hip OA, and could have implications for disease progression through altered mechano-biological processes within the joint.

Joint Loading in the Sagittal Plane During Gait Is Associated With Hip Joint Abnormalities in Patients With Femoroacetabular Impingement

BACKGROUND

Femoroacetabular impingement (FAI) is a morphological abnormality of the hip joint that results in functional impairments during various activities of daily living (ADL) such as walking. Purpose/Hypothesis: The purpose of this study was to determine if lower extremity joint loading differed between patients with FAI and controls and to determine whether these altered biomechanical parameters were associated with intra-articular abnormalities. It was hypothesized that patients with FAI would exhibit altered lower extremity joint loading during walking when compared with healthy controls and that these altered joint loading patterns would be associated with intra-articular abnormalities.

STUDY DESIGN

Controlled laboratory study.

METHODS

Lower extremity kinetics was assessed during walking at a self-selected speed in 15 presurgical patients with FAI and 34 healthy controls matched for age and body mass index. All participants underwent unilateral hip magnetic resonance imaging (MRI) to assess hip joint abnormalities. Hip joint abnormalities were assessed using a semiquantitative MRI-based scoring system. Self-reported outcomes of pain and function were obtained using the Hip disability and Osteoarthritis Outcome Score (HOOS), and physical performance was measured using the 6-minute walk test (6MWT). Group differences were assessed using an independent t test and analysis of variance. In the patients with FAI, associations of joint kinetics with HOOS subscores and intra-articular abnormalities were assessed using the Pearson ( r) and Spearman (ρ) correlation coefficients, respectively.

RESULTS

Compared with the control group, the FAI group exhibited a significantly increased severity of acetabular (FAI: 1.87 ± 1.55; control: 0.47 ± 0.79; P < .001) and femoral (FAI: 3.27 ± 2.79; control: 1.21 ± 1.55; P = .002) cartilage abnormalities, increased levels of pain (FAI: 65.0 ± 18.8; control: 98.2 ± 3.4; P = .001), and reduced function (FAI: 67.2 ± 21.5; control: 98.9 ± 3.4; P < .001) but similar walking speeds (FAI: 1.55 ± 0.19 m/s; control: 1.63 ± 0.22 m/s; P = .20) and 6MWT performance (FAI: 628.0 ± 91.2 m; control: 667.2 ± 73.4 m; P = .13). The FAI group demonstrated increased hip flexion moment impulses (FAI: 0.14 ± 0.04 N·m·s/kg; control: 0.11 ± 0.03 N·m·s/kg; P = .03), peak ankle dorsiflexion moments (FAI: 1.64 ± 0.16 N·m/kg; control: 1.46 ± 0.31 N·m/kg; P = .04), and ankle dorsiflexion moment impulses (FAI: 0.39 ± 0.07 N·m·s/kg; control: 0.31 ± 0.07 N·m·s/kg; P = .01) compared with the control group. Within the FAI group, an increased hip flexion moment impulse during walking was significantly correlated with increased pain ( r = -0.60, P = .03), decreased ADL ( r = -0.57, P = .04), and increased severity of acetabular cartilage abnormalities (ρ = 0.82, P < .01).

CONCLUSION

Patients with FAI exhibited altered hip and ankle joint loading patterns during walking. These data suggest that patients with FAI demonstrate both local and distal joint alterations during walking and that hip joint loading is directly related to hip joint abnormalities.

CLINICAL RELEVANCE

The results of this study suggest that the hip flexion moment impulse may be an important biomechanical parameter to understand FAI, as the hip flexion moment impulse during walking was shown to be directly related to hip joint abnormalities on MRI.

Associations of radiographic degeneration and pain with daily cumulative hip loading in patients with secondary hip osteoarthritis

The purpose of this study was to investigate the associations of radiographic and clinical variables of hip osteoarthritis (OA) with alterations in gait and joint loading in patients with secondary hip OA. Fifty females with secondary hip OA were participated. The minimum joint space width (mJSW) of the hip as a degenerative sign and Sharp and center edge (CE) angles as morphological variables were measured radiographically. Hip joint pain was assessed using a visual analog scale. As gait variables, walking speed, range of hip motion, hip moment peak, and hip moment impulse were calculated. Daily cumulative hip loading was calculated as the hip moment impulse multiplied by the mean number of steps per day. After bivariate correlation analyses between dependent (mJSW and pain) and independent variables (age, body mass index, sharp/CE angles, steps per day, and gait variables), separate forward-backward stepwise multiple regression analyses were performed for each dependent variable. Daily cumulative hip loading in the sagittal plane (β = 0.30, p = 0.021) and age (β = -0.36, p = 0.007) were significantly associated with the mJSW. Walking speed (β = -0.36, p = 0.008) and age (β = 0.29, p = 0.031) were significantly associated with hip joint pain. Decrease in daily cumulative hip loading in the sagittal plane was associated with mJSW independently of age. Although the causal relationship was not clear, patients with hip OA reduced total exposure to hip joint loading adaptively rather than lowering the hip moment peak concerning worsening of hip degeneration. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1977-1983, 2016.

Abnormal Joint Moment Distributions and Functional Performance During Sit-to-Stand in Femoroacetabular Impingement Patients

BACKGROUND

Femoroacetabular impingement (FAI) is a morphological abnormality of the hip joint that causes pain when performing a mechanically demanding activity of daily living such as the sit-to-stand (STS) task. Previous studies have assessed lower extremity joint mechanics during an STS task in various pathologies, yet the STS task has not been studied in FAI patients.

OBJECTIVE

The objective of this study was to identify differences in joint kinetics and performance between FAI patients and healthy controls during a STS task. It was hypothesized that FAI patients would exhibit altered time needed to complete the STS task, as well as altered lower extremity biomechanics, when compared to healthy controls.

DESIGN

This was a cross-sectional cohort study.

SETTING

The study took place at a motion capture laboratory at an institutional orthopedic facility.

PARTICIPANTS

Biomechanical analysis was performed in 17 FAI patients and 31 age- and body mass index (BMI)-matched healthy controls during the STS task.

METHODS

Sagittal plane joint moments, total support moment (TSM), joint contributions to the TSM, and functional measures during the STS task were compared between groups.

MAIN OUTCOME MEASUREMENTS

Peak joint moments, TSM and joint contributions to the TSM were assessed during the STS task. In addition, the time to and value of the peak vertical ground reaction force (vGRF), limb symmetry index at peak vGRF, loading rate, and total time needed to perform the STS task were determined.

RESULTS

Compared to the control participants, the FAI patients exhibited worse Hip Disability and Osteoarthritis Outcome Score (HOOS) pain and function subscores. No group differences were observed in peak sagittal joint moments during the STS task. However, when compared to controls, the FAI patients demonstrated reduced knee joint contributions to the TSM. In addition, the FAI patients exhibited increased time needed to perform the STS task, increased time to reach peak vGRF, and reduced lower extremity loading rate during the STS task.

CONCLUSIONS

FAI patients demonstrated abnormal joint contributions to TSM and altered functional performance during the STS task. These altered movement patterns during the STS task may be compensatory mechanisms used by the FAI patients to reduce pain and to improve function.

LEVEL OF EVIDENCE

Not applicable.

Radiographic and clinical factors associated with one-leg standing and gait in patients with mild-to-moderate secondary hip osteoarthritis

A decline in physical function associated with secondary hip osteoarthritis (OA) may be caused by both radiographic and clinical factors; however, the underlying mechanism remains unclear. The purpose of this study was to determine how joint degeneration, hip morphology, pain, hip range of motion (ROM), and hip muscle strength relate to one-leg standing (OLS) and gait in patients with mild-to-moderate secondary hip osteoarthritis. Fifty-five female patients (ages 22-65 years) with mild-to-moderate hip OA secondary to hip dysplasia were consecutively enrolled. Balance during OLS and three-dimensional hip angle changes while maintaining the OLS and at foot-off of the raised leg were measured. Gait speed and peak three-dimensional hip joint angles during gait were also measured. The associations between dependent variables (balance, gait speed, and hip kinematic changes) and independent variables (age, body mass index, pain, joint degeneration, hip morphologic abnormality, passive hip ROM, and hip muscle strength) were determined. While lower hip muscle strength was associated with hip kinematic changes such as flexion and internal rotation while maintaining OLS, decreased acetabular head index (AHI) and increased pain were associated with hip extension and abduction at foot-off in OLS. Decreased passive hip ROM was associated with decreased peak hip angles (extension, adduction, and external and internal rotation) during gait, although increased pain and decreased hip extension muscle strength were associated with slower gait speed. In this study of patients with secondary hip OA, AHI, pain, and hip impairments were associated with OLS and gait independently from age and radiographic degeneration.

Kinematic gait patterns and their relationship to pain in mild-to-moderate hip osteoarthritis

BACKGROUND

Mild-to-moderate hip osteoarthritis is often managed clinically in a non-surgical manner. Effective non-surgical management of this population requires characterizing the specific impairments within this group. To date, a complete description of all lower extremity kinematics in mild-to-moderate hip osteoarthritis patients has not been presented. The aim of the present study is to describe the lower extremity gait kinematics in mild-to-moderate hip osteoarthritis patients and explore the relationship between kinematics and pain.

METHODS

22 subjects with mild-to-moderate radiographic hip osteoarthritis (Kellgren-Lawrence grade 2-3) and 22 healthy age and BMI matched control subjects participated. Kinematic treadmill walking data were collected across all lower extremity joints. A two-way repeated measures analysis of variance estimated mean differences in gait kinematics between groups. Correlations between gait kinematics and pain were assessed using a Spearman correlation coefficient.

FINDINGS

Hip osteoarthritis subjects hiked their unsupported hemi-pelvis 1.40° (P<0.001) more than controls and tilted their pelvis 4.65° more anteriorly (P=0.01). Osteoarthritis subjects walked with 4.30° more peak hip abduction (P<0.001), 8.57° less peak hip extension (P<0.001), and 10.54° more peak hip external rotation (P<0.001). Kinematics were related to pain in the ankle frontal plane only (r=-0.43, P<0.05).

INTERPRETATION

Individuals with mild-to-moderate hip osteoarthritis demonstrate altered gait biomechanics not related to pain. These altered biomechanics may represent effective therapeutic targets by clinicians working with this population. Understanding the underlying patho-anatomic changes that lead to these biomechanical changes requires further investigation.

Longitudinal assessment of MRI in hip osteoarthritis using SHOMRI and correlation with clinical progression

PURPOSE

To assess the evolution of MR imaging findings in normal volunteers and subjects with hip osteoarthritis (OA) over 1.5 years described by the semi-quantitative Scoring Hip OA with MRI (SHOMRI) scoring system and their correlation with the evolution of clinical parameters.

MATERIALS AND METHODS

Hip MRI studies of 18 subjects with [Kellgren-Lawrence (KL) score = 2/3; mean age = 54.4 ± 11.2 years; 27.8% women] and 36 controls without radiographic OA [KL = 0/1; mean age = 43.7 ± 12.8 years; 50.0% women] were assessed at baseline and after 1.5 years by using SHOMRI, and their clinical status was evaluated by using Harris Hip Score and Hip Disability and Osteoarthritis Outcome Score (HOOS). Imaging and clinical parameters at baseline and their change over time were compared between groups using Mann-Whitney U and Fisher׳s exact tests. Spearman׳s rank correlations and generalized linear models adjusted for age, sex, BMI, and KL were used to assess associations between imaging and clinical findings.

RESULTS

At baseline, OA subjects had significantly higher SHOMRI total scores than controls [median (IQR): 12.5 (6-19.5) vs. 7 (4-13.5); p = 0.024]. Over 1.5 years, only the progression rate of subchondral cysts was significantly higher in OA subjects than in controls (16.7% vs. 0.0%; p = 0.033), while no significant differences were found for any of the other SHOMRI subscales. Baseline bone-marrow edema pattern (BMEP) was significantly associated with worsening pain (HOOS subscale; p = 0.018) and hip-related quality of life (HOOS subscale; p = 0.044). Progression of subchondral cysts was significantly associated with worsening symptoms other than pain (HOOS subscale, p = 0.030). Baseline KL did not significantly correlate with worsening of any clinical symptoms (each, p > 0.05).

CONCLUSION

In this relatively young study population without or with mild to moderate radiographic hip OA, only minimal differences were found between groups regarding the progression of hip abnormalities as assessed by SHOMRI over 1.5 years. However, BMEP predicted clinical worsening and subchondral cyst progression was associated with worsening symptoms. Although longer follow-up periods are required, this suggests that SHOMRI is a useful tool to monitor hip abnormalities and their progression longitudinally.

Association of hip pain with radiographic evidence of hip osteoarthritis: diagnostic test study

STUDY QUESTION

Is there concordance between hip pain and radiographic hip osteoarthritis?

METHODS

In this diagnostic test study, pelvic radiographs were assessed for hip osteoarthritis in two cohorts: the Framingham Osteoarthritis Study (community of Framingham, Massachusetts) and the Osteoarthritis Initiative (a multicenter longitudinal cohort study of osteoarthritis in the United States). Using visual representation of the hip joint, participants reported whether they had hip pain on most days and the location of the pain: anterior, groin, lateral, buttocks, or low back. In the Framingham study, participants with hip pain were also examined for hip pain with internal rotation. The authors analysed the agreement between radiographic hip osteoarthritis and hip pain, and for those with hip pain suggestive of hip osteoarthritis they calculated the sensitivity, specificity, positive predictive value, and negative predictive value of radiographs as the diagnostic test.

STUDY ANSWER AND LIMITATIONS

In the Framingham study (n=946), only 15.6% of hips in patients with frequent hip pain showed radiographic evidence of hip osteoarthritis, and 20.7% of hips with radiographic hip osteoarthritis were frequently painful. The sensitivity of radiographic hip osteoarthritis for hip pain localised to the groin was 36.7%, specificity 90.5%, positive predictive value 6.0%, and negative predictive value 98.9%. Results did not differ much for hip pain at other locations or for painful internal rotation. In the Osteoarthritis Initiative study (n=4366), only 9.1% of hips in patients with frequent pain showed radiographic hip osteoarthritis, and 23.8% of hips with radiographic hip osteoarthritis were frequently painful. The sensitivity of definite radiographic hip osteoarthritis for hip pain localised to the groin was 16.5%, specificity 94.0%, positive predictive value 7.1%, and negative predictive value 97.6%. Results also did not differ much for hip pain at other locations.

WHAT THIS STUDY ADDS

Hip pain was not present in many hips with radiographic osteoarthritis, and many hips with pain did not show radiographic hip osteoarthritis. Most older participants with a high suspicion for clinical hip osteoarthritis (groin or anterior pain and/or painful internal rotation) did not have radiographic hip osteoarthritis, suggesting that in many cases, hip osteoarthritis might be missed if diagnosticians relied solely on hip radiographs.

FUNDING, COMPETING INTERESTS, DATA SHARING

See the full paper on thebmj.com for funding. The authors have no competing interests. Additional data are available from bevochan@bu.edu.

Acetabular cartilage defects cause altered hip and knee joint coordination variability during gait

BACKGROUND

Patients with acetabular cartilage defects reported increased pain and disability compared to those without acetabular cartilage defects. The specific effects of acetabular cartilage defects on lower extremity coordination patterns are unclear. The purpose of this study was to determine hip and knee joint coordination variability during gait in those with and without acetabular cartilage defects.

METHODS

A combined approach, consisting of a semi-quantitative MRI-based quantification method and vector coding, was used to assess hip and knee joint coordination variability during gait in those with and without acetabular cartilage lesions.

FINDINGS

The coordination variability of the hip flexion-extension/knee rotation, hip abduction-adduction/knee rotation, and hip rotation/knee rotation joint couplings were reduced in the acetabular lesion group compared to the control group during loading response of the gait cycle. The lesion group demonstrated increased variability in the hip flexion-extension/knee rotation and hip abduction-adduction/knee rotation joint couplings, compared to the control group, during the terminal stance/pre-swing phase of gait.

INTERPRETATION

Reduced variability during loading response in the lesion group may suggest reduced movement strategies and a possible compensation mechanism for lower extremity instability during this phase of the gait cycle. During terminal stance/pre-swing, a larger variability in the lesion group may suggest increased movement strategies and represent a compensation or pain avoidance mechanism caused by the load applied to the hip joint.