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.     

Subject-specific hip geometry and hip joint centre location affects calculated contact forces at the hip during gait

Hip loading affects the development of hip osteoarthritis, bone remodelling and osseointegration of implants. In this study, we analyzed the effect of subject-specific modelling of hip geometry and hip joint centre (HJC) location on the quantification of hip joint moments, muscle moments and hip contact forces during gait, using musculoskeletal modelling, inverse dynamic analysis and static optimization. For 10 subjects, hip joint moments, muscle moments and hip loading in terms of magnitude and orientation were quantified using three different model types, each including a different amount of subject-specific detail: (1) a generic scaled musculoskeletal model, (2) a generic scaled musculoskeletal model with subject-specific hip geometry (femoral anteversion, neck-length and neck-shaft angle) and (3) a generic scaled musculoskeletal model with subject-specific hip geometry including HJC location. Subject-specific geometry and HJC location were derived from CT. Significant differences were found between the three model types in HJC location, hip flexion–extension moment and inclination angle of the total contact force in the frontal plane. No model agreement was found between the three model types for the calculation of contact forces in terms of magnitude and orientations, and muscle moments. Therefore, we suggest that personalized models with individualized hip joint geometry and HJC location should be used for the quantification of hip loading. For biomechanical analyses aiming to understand modified hip joint loading, and planning hip surgery in patients with osteoarthritis, the amount of subject-specific detail, related to bone geometry and joint centre location in the musculoskeletal models used, needs to be considered.     

Concentrations of trace elements in bones of the hip joint from patients after hip replacement surgery

The aim of this research was to determine the concentrations of two essential elements (copper (Cu) and zinc (Zn)) and three toxic elements (lead (Pb), cadmium (Cd) and mercury (Hg)) in the hip joint bones of patients from the Chair and Clinic of Orthopaedics and Traumatology at the Pomeranian Medical University in Szczecin. We examined 111 samples of hip joint bones obtained from patients from north-western Poland who had undergone arthroplasty of the femoral head. In cartilage with the adjacent compact bone, and in spongy bone from the examined patients, the concentrations (medians) determined were placed in the following descending sequence Zn>Pb>Cu>Cd>Hg. The concentrations ranged from 86 mg Zn/kg to 0.0020 mg Hg/kg dw. It was found that the concentration of lead in the cartilage with adjacent compact bone was higher in men than in women. In conclusion, it seems that in addition to routine monitoring of the abiotic environment, it is essential to monitor concentrations of heavy metals having a long-term impact in humans.     

Congenital dislocation of the hip

In surgical skin planing steel wire brushes have been largely replaced by the less hazardous diamond chip burs or "fraises" and serrated steel wheels. In addition to acne pits and wrinkling, multiple actinic (senile) keratoses are an important indication for planing. Planing provides a nonscarring method for the treatment of existing keratoses, as well as a prophylaxis against skin cancer by replacing the sun-damaged, precancerous epidermis with new epidermal cells derived from the cutaneous adnexa (pilosebaceous and sweat gland units). There are clinical landmarks indicating the depth of planing which can serve as a guide to the operator and can be correlated with microscopic findings. The results of experiments on the comparative effects of refrigerants on animal and human skin indicate that human facial skin can tolerate considerable freezing with ethyl chloride or dichlorotetrafluoroethane (Freon 114) but that mixtures containing large proportions of the much colder dichlorodifluoromethane (Freon 12) may be undesirable. Refreezing an area of the skin in order to perform a more adequate planing is not considered hazardous.THE REGENERATION OF THE SKIN FOLLOWING PLANING HAS THREE COMPONENTS: Epidermal, adnexal and dermal. The cells of the epidermis and the adnexa are equipotential. A knowledge of the anatomy of the acne pit enables the operator to decide which pits can be benefited by planing and which should be excised before planing. The successful treatment of acne pits of the face by planing in patients having keloids elsewhere on the body is reported.     

Different hip rotations influence hip abductor muscles activity during isometric side-lying hip abduction in subjects with gluteus medius weakness

The purpose of this study was to establish the effects of different hip rotations during isometric side-lying hip abduction (SHA) in subjects with gluteus medius (Gmed) weakness by investigating the electromyographic (EMG) amplitude of the Gmed, tensor fasciae latae (TFL) activity, and gluteus maximus (Gmax), and the activity ratio of the Gmed/TFL, Gmax/TFL, and Gmed/Gmax. Nineteen subjects with Gmed weakness were recruited for this study. Subjects performed three isometric hip abductions: frontal SHA with neutral hips (SHA-N), frontal SHA with hip medial rotation (SHA-MR), and frontal SHA with hip lateral rotation (SHA-LR). Surface EMG amplitude was measured to collect the EMG data from the Gmed, TFL, and Gmax. A one-way repeated-measures analysis of variance was used to determine the statistical significance of the Gmed, TFL, and Gmax EMG activity and the Gmed/TFL, Gmax/TFL, and Gmed/Gmax EMG activity ratios. Gmed EMG activity was significantly greater in SHA-MR than in SHA-N. TFL EMG activity was significantly greater in SHA-LR than in SHA-N. The Gmed/TFL and Gmed/Gmax EMG activity ratios were also significantly greater in SHA-MR than in SHA-N or SHA-LR. The results of this study suggest that SHA-MR can be used as an effective method to increase Gmed activation and to decrease TFL activity during SHA exercises.     

Soft tissue stiffness over the hip increases with age and its implication in hip fracture risk in older adults

Risk of hip fracture depends on the bone strength as well as the impact force delivered to the proximal femur during falls, and femoral soft tissue may help to reduce the hip fracture risk by attenuating the impact force. Femoral soft tissue stiffness was measured from a large sample, and compared how this was affected by age, gender and site.One hundred fifty healthy individuals (fifty-two young (aged between 19 and 29), forty-eight middle-aged (30–64), and fifty old (over 65)) participated. Each age group included an equal number of males and females. Using an automated hand-held indentation device, soft tissue stiffness was measured over twelve sites with respect to the greater trochanter (GT).For both left and right hips, the stiffness was associated with age (p < 0.0005), gender (p < 0.0005), and site (p < 0.0005). On average, the stiffness was 26% greater in older than young adults (321.5 versus 254.3 N/m). On average across twelve sites, the regression analysis indicated that the stiffness increases 1.33 N/m every year (“soft tissue stiffness over the hip = 1.33*age + 221.8”; R = 0.518, p < 0.0005). Furthermore, the stiffness was 18% greater in male than female (308.8 versus 262.6 N/m), and differed across twelve sites over the hip, being greatest (424.2 N/m) at the GT, and least (206.3 N/m) at the superior gluteal region.The results provide insights into the shock absorbing property of soft tissue over the hip, and inform the improvement of fall-related injury prevention interventions (i.e., hip protector, safe landing strategies) in older adults.