Cross-cultural consensus for waist–hip ratio and women's attractiveness

In women of reproductive age, a gynoid body fat distribution as measured by the size of waist–hip ratio (WHR) is a reliable indicator of their sex hormone profile, greater success in pregnancy and less risk for major diseases. According to evolutionary mate selection theory, such indicators of health and fertility should be judged as attractive. Previous research has confirmed this prediction. In this current research, we use the same stimulus for diverse racial groups (Bakossiland, Cameroon, Africa; Komodo Island, Indonesia; Samoa; and New Zealand) to examine the universality of relationships between WHR and attractiveness. As WHR is positively correlated with body mass index (BMI), we controlled BMI by using photographs of women who have gone through micrograft surgery for cosmetic reasons. Results show that in each culture participants selected women with low WHR as attractive, regardless of increases or decreases in BMI. This cross-cultural consensus suggests that the link between WHR and female attractiveness is due to adaptation shaped by the selection process.     

Does gender influence neuromotor control of the knee and hip?

Patellofemoral pain (PFP) is a common condition that occurs more frequently in females. Anatomical, hormonal and neuromuscular factors have been proposed to contribute to the increased incidence of PFP in females, with neuromuscular factors considered to be of particular importance. This cross-sectional study aimed to evaluate differences in the neuromotor control of the knee and hip muscles between genders and to investigate whether clinical measures of hip rotation range and strength were associated with EMG measures of hip and thigh motor control. Twenty-nine (16 female and 13 male) asymptomatic participants completed a visual choice reaction-time stair stepping task. EMG activity was recorded from vastus medialis oblique, vastus lateralis, anterior and posterior gluteus medius muscles. In addition hip rotation range of motion and hip external rotation, abduction and trunk strength were assessed. There were no differences in the timing or peak of EMG activation of the vasti or gluteus medius muscle between genders during the stepping task. There were however significant associations between EMG measures of motor control of the vasti and hip strength in both females and males. These findings are suggestive of a link between hip muscle control and vasti neuromotor control.     

Implant–bone interface healing and adaptation in resurfacing hip replacement

Hip resurfacing demonstrates good survivorship as a treatment for young patients with osteoarthritis, but occasional implant loosening failures occur. On the femoral side there is radiographic evidence suggesting that the implant stem bears load, which is thought to lead to proximal stress shielding and adaptive bone remodelling. Previous attempts aimed at reproducing clinically observed bone adaptations in response to the implant have not recreated the full set of common radiographic changes, so a modified bone adaptation algorithm was developed in an attempt to replicate more closely the effects of the prosthesis on the host bone. The algorithm features combined implant–bone interface healing and continuum bone remodelling. It was observed that remodelling simulations that accounted for progressive gap filling at the implant–bone interface predicted the closest periprosthetic bone density changes to clinical X-rays and DEXA data. This model may contribute to improved understanding of clinical failure mechanisms with traditional hip resurfacing designs and enable more detailed pre-clinical analysis of new designs.     

Trunk and hip muscle activity in early walkers with and without cerebral palsy – A frequency analysis

Poor control of postural muscles is a primary impairment in cerebral palsy (CP), yet core trunk and hip muscle activity has not been thoroughly investigated. Frequency analysis of electromyographic (EMG) signals provides insight about the intensity and pattern of muscle activation, correlates with functional measures in CP, and is sensitive to change after intervention. The objective of this study was to investigate differences in trunk and hip muscle activation frequency in children with CP compared to children with similar amounts of walking experience and typical development (TD). EMG data from 31 children (15 with CP, 16 with TD) were recorded from 16 trunk and hip muscles bilaterally. A time–frequency pattern was generated using the continuous wavelet transform and instantaneous mean frequency (IMNF) was calculated at each interval of the gait cycle. Functional principal component analysis (PCA) revealed that IMNF was significantly higher in the CP group throughout the gait cycle for all muscles. Additionally, stride-to-stride variability was higher in the CP group. This evidence demonstrated altered patterns of trunk and hip muscle activation in CP, including increased rates of motor unit firing, increased number of recruited motor units, and/or decreased synchrony of motor units. These altered muscle activation patterns likely contribute to muscle fatigue and decreased biomechanical efficiency in children with CP.     

Orthobiologics in the treatment of hip disorders

Orthobiologics are biological materials that are intended for the regeneration or healing of bone,cartilage and soft tissues.In this review we discuss the use of orthobiologics for hip disorders providing an update.The orthobiologics included in this article are hyaluronic acid,platelet rich plasma,bone marrow,adipose tissue and expanded mesenchymal stem cells.We explain the concepts and definitions of each orthobiological product,and the literature regarding its use in the hip joint.The paucity of guidelines for the production and characterization of the biological products leads to uneven results across the literature.Each biologic therapy has indications and benefits;however,noteworthy are the characterization of the orthobiologics,the application method and outcome analysis for further improvement of each technique.     

Serum prolidase activity and oxidative–antioxidative status in patients with developmental dysplasia of the hip and its relationship with radiographic severity

Background: We aimed to investigate serum prolidase activity and to investigate its association with oxidative–antioxidative status in patients with developmental dysplasia of the hip (DDH).

Methods: Oxidative status parameters, including lipid hydroperoxide (LOOH), total oxidant status (TOS), and the oxidative stress index (OSI), and antioxidative status parameters, free sulfhydryl groups (Total –SH), and total antioxidative capacity (TAC), as well as serum prolidase activity were assessed in patients with DDH (n?=?93), and in healthy controls (n?=?82). The severity of dysplasia was evaluated according to the Tonnis grading system.

Results: Serum prolidase activity and the oxidant parameters (LOOH, TOS, and OSI) were significantly higher and the antioxidant parameters (Total –SH and TAC) were significantly lower in patients with DDH compared to the controls (P?P?P?Conclusion: Increased levels of serum prolidase activity, LOOH, TOS, and OSI, and decreased levels of total –SH and TAC, may be associated with DDH, and these parameters may be useful adjunctive tools to assess the severity of DDH.     

Gene-environment interaction between body mass index and transforming growth factor beta 1 (TGFβ1) gene in knee and hip osteoarthritis

Introduction

The objective was to investigate potential gene-environment interaction between body mass index (BMI) and each of eight TGFβ1 polymorphisms in knee and hip osteoarthritis (OA).

Methods

We conducted a case-control study of Caucasian men and women aged 45 to 86 years from Nottingham, United Kingdom (Genetics of OA and Lifestyle (GOAL) study). Cases had clinically severe symptoms and radiographic knee or hip OA; controls had no symptoms and no radiographic knee/hip OA. We used logistic regression to investigate the association of TGFβ1 polymorphisms and OA when stratifying by BMI. Knee and hip OA were analyzed separately with adjustment for potential confounders. Additive and multiplicative interactions were examined.

Results

2,048 cases (1,042 knee OA, 1,006 hip OA) and 967 controls were studied. For hip OA, the highest risk was in overweight (BMI ≥25 kg/m²) individuals with the variant allele of single-nucleotide polymorphism (SNP) rs1800468 (odds ratio (OR) 2.21, 95% confidence interval (CI) 1.55, 3.15). Evaluation of gene-environment interaction indicated significant synergetic interaction (relative excess risk due to interaction (RERI) = 0.93, synergy index (SI) = 4.33) with an attributable proportion due to interaction (AP) of 42% (AP = 0.42; 95% CI 0.16, 0.68). Multiplicative interaction was also significant (OR for interaction (ORINT) = 2.27, P = 0.015). For knee OA, the highest risk was in overweight individuals with homozygous genotype 11 of SNP rs2278422 (OR = 6.95, P <0.001). In contrast, the variant allele indicated slightly lower risks (OR = 4.72, P <0.001), a significant antagonistic interaction (RERI = -2.66, SI = 0.59), AP = -0.56 (95%CI -0.94, -0.17) and a significant multiplicative interaction (ORINT = 0.47, P = 0.013).

Conclusion

TGFβ1 gene polymorphisms interact with being overweight to influence the risk of large joint OA.     

Spontaneous whole body rotations and classical dance expertise: How shoulder–hip coordination influences supporting leg displacements

The link between supporting leg stability and individual trunk strategies used during spontaneous whole-body rotations was studied according to visual and kinesthetic imagery styles for classical dancers and untrained female participants. Shoulders–hip angles in the horizontal plane and supporting leg (SL) displacements were analyzed with three-dimensional kinematic at the beginning and end of the four turns, identified according to their SL (left vs. right) and turn direction (clockwise, CW vs. counterclockwise, CCW). To begin a turn in CCW on left SL, all the participants turned shoulders before hips (?25° angle), p < 0.01. Untrained participants yielded the reverse (+30° angle) in CW – their non-preferred turn - whereas dancers maintained their trunk en bloc. In the turn slow down, in their preferred direction all the participants adopted en bloc behavior to avoid imbalance. Dancers kept this pattern in CCW but untrained participants separated shoulders and hips, p < 0.01; on left SL (+20° angle) hips finished before shoulders and on right SL (?25° angle), shoulders finished before hips. Both mental imagery styles and spatial context link reduction of shoulder–hip angle and stability of SL. Daily expertise, not only dance training, facilitates the en bloc shoulder–hip coordination to maintain equilibrium.     

Do capsular pressure and implant motion interact to cause high pressure in the periprosthetic bone in total hip replacement?

When there is a debonding at the bone-implant interface, the difference in stiffness between the implant and the bone can result in micromotion, allowing existing gaps to open further or new gaps to be created during physiological loading. It has been suggested that periprosthetic fluid flow and high pressure may play an important role in osteolysis development in the proximity of these gaps. To explain this phenomenon, the concepts of "effective joint space" and "pumping stem" have been cited in many studies. However, there is no clear understanding of the factors causing, or contributing to, these mechanisms. It is likely that capsular pressure, gap dimensions, and micromotion of the gap during cyclic loading of an implant can play a defining role in inducing periprosthetic flow. In order to obtain a better understanding of the main influences on periprosthetic flows and the development of osteolysis, steady state and transient 2D computational fluid dynamic simulations were performed for the joint capsule of the lateral side of a stem-femur system, and a gap in communication with the capsule and the surrounding bone. It was shown that high capsular pressure may be the main driving force for high fluid pressure and flow in the bone surrounding the gap, while micromotion of only very long and narrow gaps can cause significant pressure and flow in the bone. At low capsular pressure, micromotion induced large flows in the gap region; however, the flow in the bone tissue was almost unaffected. The results also revealed the existence of high velocity spikes in the bone region at the bottom of the gap. These velocity spikes can exert excessive fluid shear stress on the bone cells and disturb the local biological balance of the surrounding interstitial fluid which can result in osteolysis development. High capsular pressure was observed to be the main cause of these velocity spikes whereas, at low capsular pressure, gap micromotion of only very long and narrow gaps generated significant velocity spikes in the bone at the bottom of the gaps.     

Early cartilage abnormalities at the hip are associated with obesity and body composition measures – a 3.0T MRI community-based study

IntroductionAlthough obesity is a risk factor for hip osteoarthritis (OA), the role of body composition, if any, is unclear. This study examines whether the body mass index (BMI) and body composition are associated with hip cartilage changes using magnetic resonance imaging (MRI) in community-based adults.Methods141 community-based participants with no clinical hip disease, including OA, had BMI and body composition (fat mass and fat free mass) measured at baseline (1990 to 1994), and BMI measured and 3.0 T MRI performed at follow-up (2009–2010). Femoral head cartilage volume was measured and femoral head cartilage defects were scored in the different hip regions.ResultsFor females, baseline BMI (β = −26 mm³, 95% Confidence interval (CI) -47 to −6 mm³, p = 0.01) and fat mass (β = −11 mm³, 95% CI −21 to −1 mm³, p = 0.03) were negatively associated with femoral head cartilage volume. Also, while increased baseline fat mass was associated with an increased risk of cartilage defects in the central superolateral region of the femoral head (Odds Ratio (OR) = 1.08, 95% CI 1.00–1.15, p = 0.04), increased baseline fat free mass was associated with a reduced risk of cartilage defects in this region (OR = 0.82, 95% CI 0.67–0.99; p = 0.04). For males, baseline fat free mass was associated with increased femoral head cartilage volume (β = 40 mm³, 95% CI 6 to 74 mm³, p = 0.02).ConclusionsIncreased fat mass was associated with adverse hip cartilage changes for females, while increased fat free mass was associated with beneficial cartilage changes for both genders. Further work is required to determine whether modifying body composition alters the development of hip OA.     

Radiotherapy induced hip joint avascular necrosis—Two cases report

Background

Avascular necrosis (AVN) refers to the death of osteocytes and osteoblasts. Sites such as the femoral head, the head of the humerus and the mandibula with restricted access to local blood supply are particularly vulnerable to osteonecrosis.A combination of several factors is responsible for ischaemia and is associated with AVN: corticosteroids, alcohol abuse, Cushing''s syndrome, SLE, systemic vasculitis, RA, scleroderma, haemoglobinopathies, radiotherapy. Management is based on proper diagnosis and treatment – conservative, pharmacological or surgical.Radiotherapy has become an integral part of the therapeutic programme of cancer patients. However, early and late after-effects of irradiation still constitute a significant issue in clinical practice.

Aim

The aim of this report is to present two cases of acetabular protrusion and femoral head deformities after a therapeutic pelvic irradiation and draw physicians’ attention to that clinical problem which continues to be underestimated.

Materials and methods

This report documents two cases of acetabular protrusion and femoral head deformities after a therapeutic pelvic radiation.

Results

Avascular necrosis (AVN) constitutes a severe and challenging long-term complication in radiation oncology.

Conclusion

It is necessary to take into account bone structures among organ at risk (OAR) involved in irradiation fields. The detailed analysis of the dose distribution and the use of collimators allow to decrease the total dose to OAR.An adequate management, early diagnosis and prompt, proper treatment may protect patients from long-term morbidities.     

Are geriatric units needed for elderly patients with hip fractures?

To assess the need for a multidisciplinary geriatric unit in the treatment of elderly patients with hip fractures, we reviewed the charts of all patients aged 60 years or older who were treated for hip fractures in five hospitals in Hamilton, Ont., between August 1982 and September 1983. We hypothesized that discharge to a different location from that before admission would indicate reduced functional status and classified the reasons for a change in residence as poor patient motivation, need for rehabilitation, compromised ambulation, postoperative complications and inevitable deterioration. We believed that geriatric care would be most beneficial to those in the first three groups. Of the 327 patients with hip fractures 40 (12%) died before discharge. Of the 287 surviving patients 149 (52%) had been discharged by 4 weeks, and only 29 (10%) remained in hospital by 12 weeks. Of the 287, 44 (15%) were discharged to a different location from that before admission: in 75% the cause appeared to be inevitable deterioration (57%) or postoperative complications (18%). The remaining 25% needed rehabilitation and were all sent to appropriate facilities. None of the patients with ambulation problems or poor motivation required an increased level of care. We could not show a need for geriatric care in our population; possible explanations are discussed.     

Bone geometry of the hip is associated with obesity and early structural damage – a 3.0 T magnetic resonance imaging study of community-based adults

IntroductionThe mechanism by which obesity increases the risk of hip osteoarthritis is unclear. One possibility may be by mediating abnormalities in bony geometry, which may in turn be associated with early structural abnormalities, such as cartilage defects and bone marrow lesions.MethodsOne hundred and forty one older adults with no diagnosed hip osteoarthritis had weight and body mass index measured between 1990 and 1994 and again in 2009 to 2010. Acetabular depth and lateral centre edge angle, both measures of acetabular over-coverage, as well as femoral head cartilage volume, cartilage defects and bone marrow lesions were assessed with 3.0 T magnetic resonance imaging performed in 2009 to 2010.ResultsCurrent body mass index, weight and weight gain were associated with increased acetabular depth and lateral centre edge angle (all P ≤ 0.01). For every 1 mm increase in acetabular depth, femoral head cartilage volume reduced by 59 mm³ (95% confidence interval (CI) 20 mm³ to 98 mm³, P < 0.01). Greater acetabular depth was associated with an increased risk of cartilage defects (odds ratio (OR) 1.22, 95% CI 1.03 to 1.44, P = 0.02) and bone marrow lesions (OR 1.29, 95% CI 1.01 to 1.64, P = 0.04) in the central region of the femoral head. Lateral centre edge angle was not associated with hip structure.ConclusionsObesity is associated with acetabular over-coverage. Increased acetabular depth, but not the lateral centre edge angle, is associated with reduced femoral head cartilage volume and an increased risk of cartilage defects and bone marrow lesions. Minimising any deepening of the acetabulum (for example, through weight management) might help to reduce the incidence of hip osteoarthritis.     

Assessment of the validity of the Biering-Sørensen test for measuring back muscle fatigue based on EMG median frequency characteristics of back and hip muscles

The aims of the present study were (1) to investigate the differences in median frequency characteristics between back and hip muscles of healthy subjects during a Biering-Sørensen test, (2) to determine if the Biering-Sørensen test is a valid test for measuring back muscle fatigue, and (3) to standardise the Biering-Sørensen test by using objective movement analysis when defining endurance time, and compare this to the original method based on tactile feedback. Twenty healthy subjects participated in this experiment. The electromyographic activity of eight back and hip muscles was bilaterally measured. In addition three-dimensional data of the lumbar region were collected with an ultrasound movement analysis system. Median frequencies were computed from the EMG power spectra. Two methods of determining the endurance time of the Biering-Sørensen test yielded highly correlated but significantly different normalized median frequency slope values (NMF_slope). Significant differences in NMF_slope values between several back and hip muscles could be demonstrated. Low to moderate correlation coefficients were shown between NMF_slope values and endurance time. Multiple stepwise linear regression analyses revealed that only NMF_slope of the thoracic part of the iliocostalis lumborum muscle could significantly predict the test endurance time. The findings of the present study support the validity of the Biering-Sørensen test for measuring back muscle fatigue.     

How symmetric are metal-on-metal hip resurfacing patients during gait? Insights for the rehabilitation

Metal-on-metal hip resurfacing patients demonstrate hip biomechanics closer to normal in comparison to total hip arthroplasty during gait. However, it is not clear how symmetric is the gait of hip resurfacing patients. Biomechanical data of 12 unilateral metal-on-metal hip resurfacing participants were collected during gait at a mean time of 45 months (SD 24) after surgery. Ankle, knee, hip, pelvis and trunk kinematics and kinetics of both sides were measured with a motion and force-capture system. Principal component analysis and mean hypothesis’ tests were used to compare the operated and healthy sides. The operated side had prolonged ankle eversion angle during late stance and delayed increased ankle inversion angle during early swing (p = 0.008; effect size = 0.70), increased ankle inversion moment during late stance (p = 0.001; effect size = 0.78), increased knee adduction angle during swing (p = 0.044; effect size = 0.57), decreased knee abduction moment during stance (p = 0.05; effect size = 0.40), decreased hip range of motion in the sagittal plane (p = 0.046; effect size = 0.56), decreased range of hip abduction moment during stance (p = 0.02; effect size = 0.63), increased hip range of motion in the transverse plane (p = 0.02; effect size = 0.62), decreased hip internal rotation moment during the transition from loading response to midstance (p = 0.001; effect size = 0.81) and increased trunk ipsilateral lean (p = 0.03; effect size = 0.60). Therefore, hip resurfacing patients have some degree of asymmetry in long term, which may be related to hip weakness and decreased range of motion, to foot misalignments and to strategies implemented to reduce loading on the operated hip. Interventions such as muscle strengthening and stretching, insoles and gait feedback training may help improving symmetry following hip resurfacing.     

Mcconnell’s patellar taping does not alter knee and hip muscle activation differences during proprioceptive exercises: A randomized placebo-controlled trial in women with patellofemoral pain syndrome

The purpose of this study was to assess the effect of patellar taping on muscle activation of the knee and hip muscles in women with Patellofemoral Pain Syndrome during five proprioceptive exercises. Forty sedentary women with syndrome were randomly allocated in two groups: Patellar Taping (based in McConnell) and Placebo (vertical taping on patella without any stretching of lateral structures of the knee). Volunteers performed five proprioceptive exercises randomly: Swing apparatus, Mini-trampoline, Bosu balance ball, Anteroposterior sway on a rectangular board and Mediolateral sway on a rectangular board. All exercises were performed in one-leg stance position with injured knee at flexion of 30° during 15 s. Muscle activation was measured by surface electromyography across Vastus Medialis, Vastus Lateralis and Gluteus medius muscles. Maximal voluntary contraction was performed for both hip and knee muscles in order to normalize electromyography signal relative to maximum effort during the exercises. ANOVA results reported no significant interaction (P > 0.05) and no significant differences (P > 0.05) between groups and intervention effects in all exercise conditions. Significant differences (P < 0.01) were only reported between muscles, where hip presented higher activity than knee muscles. Patellar taping is not better than placebo for changes in the muscular activity of both hip and knee muscles during proprioceptive exercises. Trial registration number: ClinicalTrials.gov NCT02322515.     

Is excessive running predictive of degenerative hip disease? Controlled study of former elite athletes.

OBJECTIVE--To determine the effects of regular long distance running on the state of the hips in later life. DESIGN--Retrospective study of a cohort of elite athletes and a group of normal, healthy, untrained controls examined 15 years after initial testing. SETTING--Research project at school for physical education and sports. SUBJECTS--27 Former long distance runners (mean age 42), nine former bobsleigh riders (mean age 42), and 23 normal, healthy, untrained men (mean age 35) who had been examined in 1973 and who agreed to re-examination in 1988. MAIN OUTCOME MEASURE--Radiological evidence of degenerative hip disease in 1988. RESULTS--Physiological and exercise characteristics of all subjects had been recorded in 1973, and in 1988 these measurements were repeated together with radiological examination of the hips. An additive radiological index of hip disease based on grades of subchondral sclerosis, osteophyte formation, and joint space narrowing was significantly increased among runners as compared with bobsleigh riders and untrained controls. After adjustment for age the significant effect of type of sports activity remained (p = 0.032). In multivariate analyses age and milage run in 1973 (97 km/week) emerged as independent, significant, and positive predictors of radiological signs of degenerative hip disease in 1988 (p = 0.017 and p = 0.024 respectively). Among runners alone running pace in 1973 rather than milage run was the stronger predictor of subsequent degenerative hip disease. The milage run in 1988 was not particularly predictive of the radiological index, but endurance in 1988 was inversely related to degenerative hip disease seen radiologically. CONCLUSION--Long term, high intensity, high milage running should not be dismissed as a potential risk factor for premature osteoarthritis of the hip.