[Gluteal insufficiency: Pathogenesis, Diagnosis and Therapy]

Comparison of gluteus medius strength between individuals with obesity and normal-weight individuals: a cross-sectional study

Background

The hip abductor muscles, primarily the gluteus medius, play an important role in stabilizing the pelvis during gait. Gluteus medius weakness is associated with biomechanical changes and musculoskeletal disorders. Individuals with obesity can have great difficulty maintaining abductor muscular function due to being overweight and possibly experiencing a decrease in muscle mass. However, it is still unclear whether the musculature of person with obesity can compensate for these changes. Therefore, the aim of this study was to compare gluteus medius strength between individuals with obesity and normal-weight individuals using a digital hand-held dynamometer.

Methods

Twenty-five participants with obesity (BMI > 35 kg/m²) were matched for sex, age, and height with normal-weight individuals. Gluteus medius strength was measured by a single examiner using a belt-stabilized hand-held digital dynamometer placed on the knee of the individuals positioned in lateral decubitus. Three measurements were recorded with rest intervals, and only the highest value measured for each limb was used for analysis. The differences between pairs were calculated, and the normality of the data was assessed using the Shapiro-Wilk test (p < 0.05). The matrices of the variables were standardized and analysed using principal component analysis (PCA).

Results

For the strength variables (Newtons) on both sides, no significant differences were detected between the groups (p > 0.05). However, significant differences were detected in these variables between the groups (p < 0.05) when the measurements were normalized to body weight (Newtons/kilograms). PCA indicated that both the absolute and normalized values of strength are lower in participants with obesity than in normal-weight.

Conclusions

These findings suggest that people with obesity could have the same or less strength (PCA) to move more mass, which may imply a relative weakness that induces functional limitations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04470-8.

[Avulsion injuries of the gluteus medius and gluteus minimus muscles]

Avulsion injuries of the gluteus medius and gluteus minimus muscles represent a diagnostic and therapeutic challenge. Such injuries are rarely to be expected in high-energy trauma. Degenerative damage or iatrogenic injuries in the context of hip surgery are more frequently identified as the cause. Clinically, in addition to lateral hip pain, limping is an important finding and depends on the extent of the tendon damage. In addition to the medical history and clinical examination, imaging by means of sonography and, above all, magnetic resonance imaging (MRI, possibly with artifact-reduced sequences in the presence of an endoprosthesis) are diagnostically groundbreaking. Therapeutically, a stepwise approach is indicated according to the extent of rupture and quality of the gluteal tendon and muscle tissues. Specific conservative training regimens, mini-open/endoscopic anatomic reconstruction techniques in cases of gluteal muscle integrity and muscle transfer techniques as salvage option with chronic mass ruptures are available. The common goal is the restoration of everyday occupational and private activities to regain the quality of life.

[Gluteal insufficiency]

Gluteal insufficiency or hip abductor mechanism deficiency mainly following (revision) total hip replacement is associated with highly painful complaints and severe suffering of patients. It represents a great diagnostic and therapeutic challenge. Differentiated conservative treatment pathways, open surgical and endoscopic anatomic repair techniques with intact gluteal musculature and muscle transfer are available as salvage procedures for chronic not anatomically reconstructable mass ruptures. A stepwise diagnostic and therapeutic approach is required for restoration of the quality of life and painless or almost painless mobility of affected patients in occupation and daily life.

Hip abductor tendon pathology visualized by 1.5 versus 3. 0 Tesla MRIs

INTRODUCTION

Hip abductor tendinopathies are becoming increasingly recognized as clinically relevant disorders. However, knowledge about prevalence of abductor tendinopathies and associated disorders of adjacent hip articular and periarticular structures is limited. In this context, the relative diagnostic value of 1.5-T vs. 3.0-T MRI magnets has not been studied yet.

MATERIALS AND METHODS

Pelvic MRI scans of 1000 hips from 500 consecutive unselected patients (341 in 3.0-T/159 in 1.5-T magnets, with standardized scanning protocols over the entire study period) were analysed for the detection of abductor tendinosis, calcifying tendinitis, partial or full-thickness tears of the M. gluteus medius (GMed) and/or -minimus (GMin) and trochanteric bursitis (TB). The occurrence of these lesions was correlated to the presence of muscle atrophy (MA) of GMed/GMin, hip joint effusion (JE) and osteoarthritis (OA).

RESULTS

Peritrochanteric lesions were observed with a prevalence of 31.4% of all patients (22.3% of all hips). TB occurred almost exclusively in the presence of GMed/GMin tendinopathies. Compared to overall prevalence, patients with MA displayed lesions of GMed/GMin or TB in 70%, patients, with OA in 30% and with JE in 23%. These lesions occurred significantly more often ipsilateral to MA and OA than contralateral (MA: 76.8% vs. 23.2%, p < 0.001; OA: 64.4% vs. 35.6%, p = 0.03; JE: 62.7% vs. 37.3%, p = 0.08). Significantly more tendon lesions, in particular specific radiological diagnoses like partial/full-thickness tears, were detected by 3.0-T MRI than by 1.5 T (p = 0.019).

CONCLUSIONS

Peritrochanteric lesions are a prevalent pathology that should specifically be looked for, preferably by 3.0-T MRI, independent of concomitant hip joint pathology.