Range of Motion Simulation of Hip Joint Movement During Salat Activity

A novel intraoperative acetabular reaming center locating method in total hip arthroplasty for Crowe type IV developmental dysplasia of the hip: a retrospective cohort study

PURPOSE

Although the principles of hip reconstruction are consistent, due to lack of reliable anatomical landmarks, how to decide the acetabular cup reaming centre intraoperatively in Crowe IV patients with developmental dysplasia of the hip (DDH) remains unclear. This study aims to address this question.

METHODS

Fifty-eight Crowe IV patients were enrolled from 2017 to 2019. By examining our previous clinical data, we analyzed the anatomical morphology of Crowe IV acetabulum and proposed a method of locating intraoperative reaming centering for implantation of a standard-sized acetabular cup, which is the upper two thirds of the posterior border of the true acetabulum. All patients included in this study were reamed according to this method. The average postoperative follow-up was 4.1 years (3-5 years). The position of the centre of rotation (COR), cup coverage (CC), and optimal range of joint motion (ROM) were examined by 3D computer simulation measurement. Postoperative complications and hip Harris score were collected and analyzed.

RESULTS

The morphology of the type IV DDH true acetabulum was mostly triangular. The intraoperative reaming centre were centered on the upper two thirds of the posterior border of the true acetabulum. The postoperative 3D CC was 80.20% ± 7.63% (64.68-90.24%, 44-48-mm cup size). The patients' mean Harris score improved from 39.7 ± 20.4 preoperatively to 91.5 ± 8.12 at the last follow-up.

CONCLUSION

Our study demonstrated that satisfactory CC and clinical results could be achieved by implanting a standard-sized cup with the reaming centre on the upper two thirds of the posterior border of the true acetabulum.

Investigation of contact behavior on a model of the dual-mobility artificial hip joint for Asians in different inner liner thicknesses

BACKGROUND

The four components that make up the current dual-mobility artificial hip joint design are the femoral head, the inner liner, the outer liner as a metal cover to prevent wear, and the acetabular cup. The acetabular cup and the outer liner were constructed of 316L stainless steel. At the same time, the inner liner was made of ultra-high-molecular-weight polyethylene (UHMWPE). As this new dual-mobility artificial hip joint has not been researched extensively, more tribological research is needed to predict wear. The thickness of the inner liner is a significant component to consider when calculating the contact pressure.

AIM

To make use of finite element analysis to gain a better understanding of the contact behavior in various inner liner thicknesses on a new model of a dual-mobility artificial hip joint, with the ultimate objective of determining the inner liner thickness that was most suitable for this particular type of dual-mobility artificial hip joint.

METHODS

In this study, the size of the femoral head was compared between two diameters (28 mm and 36 mm) and eight inner liner thicknesses ranging from 5 mm to 12 mm. Using the finite element method, the contact parameters, including the maximum contact pressure and contact area, have been evaluated in light of the Hertzian contact theory. The simulation was performed statically with dissipated energy and asymmetric behavior. The types of interaction were surface-to-surface contact and normal contact behavior.

RESULTS

The maximum contact pressures in the inner liner (UHMWPE) at a head diameter of 28 mm and 36 mm are between 3.7-13.5 MPa and 2.7-10.4 MPa, respectively. The maximum von Mises of the inner liner, outer liner, and acetabular cup are 2.4-11.4 MPa, 15.7-44.3 MPa, and 3.7-12.6 MPa, respectively, for 28 mm head. Then the maximum von Mises stresses of the 36 mm head are 1.9-8.9 MPa for the inner liner, 9.9-32.8 MPa for the outer liner, and 2.6-9.9 MPa for the acetabular cup. A head with a diameter of 28 mm should have an inner liner with a thickness of 12 mm. Whereas the head diameter was 36 mm, an inner liner thickness of 8 mm was suitable.

CONCLUSION

The contact pressures and von Mises stresses generated during this research can potentially be exploited in estimating the wear of dual-mobility artificial hip joints in general. Contact pressure and von Mises stress reduce with an increasing head diameter and inner liner's thickness. Present findings would become one of the references for orthopedic surgery for choosing suitable bearing geometric parameter of hip implant.

A finite element study on the interactive effect between the damage of the cup-bone interface and the bone strain of hip implants under various fixation conditions

Interfacial damage has a high impact on the loosening of the acetabular cup. However, monitoring this damage induced by the variations in loading conditions, such as the angle, amplitude, and frequency in vivo, is challenging. In this study, we evaluated the risk of loosening of the acetabular cup due to interfacial damages induced by the deviation in loading conditions and amplitudes. A three-dimensional model of the acetabular cup component was developed, and the interfacial crack growth between the cup and the bone was modeled using a fracture mechanics approach, which simulated the extent of interfacial damage and associated cup displacement. The interfacial delamination mechanism changed with the increasing inclination angle, wherein a fixation angle of 60° exhibited the largest area of contact loss. The compressive strain of embedding the simulated bone at the remaining bonding area accumulated as the lost contact area widened. Such interfacial damages, namely, the growth of the lost contact area and accumulated compressive strain in the simulated bone, promoted both embedding and rotational displacement of the acetabular cup. In the worst case of a fixation angle of 60°, the total displacement of the acetabular cup exceeded the limit of the modified safe zone, suggesting a quantitative risk of dislocation of the acetabular cup induced by the accumulated interfacial damage. Furthermore, nonlinear regression analyses between the degree of displacement of the acetabular cup and the extent of the two types of interfacial damage demonstrated that the interactive effect of the fixation angle with the loading amplitude showed a significant effect on increasing cup displacement. These findings suggest that proper control of the fixation angle during operation is useful in preventing the loosening of the hip joint.

Morbidity and Mortality Analysis in the Treatment of Intertrochanteric Hip Fracture with Two Fixation Systems: Dynamic Hip Screw (DHS) or Trochanteric Fixation Nail Advance (TFNA)

BACKGROUND

The aim of this study was to compare the clinical outcomes, complications, and mortality of patients with intertrochanteric hip fracture treated with dynamic hip screw (DHS) vs. trochanteric fixation nail advance (TFNA).

METHODS

We evaluated 152 patients with intertrochanteric fractures concerning age, sex, comorbidity, Charlson Index, preoperative gait, OTA/AO classification, time from fracture to surgery, blood loss, amount of blood replacement, changes in gait, full weight-bearing at hospital discharge, complications, and mortality. The final indicators encompassed the adverse effects linked to implants, postoperative complications, clinical healing or bone healing duration, and functional score.

RESULTS

The study included a total of 152 patients, out of which 78 (51%) received DHS treatment and 74 (49%) received TFNA treatment. The results of this study show that the TFNA group demonstrated superiority (p < 0.001). However, it should be noted that the TFNA group had a higher frequency of the most unstable fractures (AO 31 A3, p < 0.005). Full weight-bearing at discharge also decreased in patients with more unstable fractures (p = 0.005) and severe dementia (p = 0.027). Mortality was higher in the DHS group; however, a longer time from diagnosis to surgery was also observed in this group (p < 0.005).

CONCLUSIONS

The TFNA group has shown a higher success rate in achieving full weight-bearing at hospital discharge when treating trochanteric hip fractures. This makes it the preferred choice for treating unstable fractures in this region of the hip. Additionally, it is important to note that a longer time to surgery is associated with increased mortality in patients with hip fractures.

Database covering the prayer movements which were not available previously

Lower body implants are designed according to the boundary conditions of gait data and tested against. However, due to diversity in cultural backgrounds, religious rituals might cause different ranges of motion and different loading patterns. Especially in the Eastern part of the world, diverse Activities of Daily Living (ADL) consist of salat, yoga rituals, and different style sitting postures. A database covering these diverse activities of the Eastern world is non-existent. This study focuses on data collection protocol and the creation of an online database of previously excluded ADL activities, targeting 200 healthy subjects via Qualisys and IMU motion capture systems, and force plates, from West and Middle East Asian populations with a special focus on the lower body joints. The current version of the database covers 50 volunteers for 13 different activities. The tasks are defined and listed in a table to create a database to search based on age, gender, BMI, type of activity, and motion capture system. The collected data is to be used for designing implants to allow these sorts of activities to be performed.

Salat dhuha effect on oxidative stress in elderly women: A randomized controlled trial

Background

The aging process and a chronic sedentary lifestyle in the elderly as a result of physical restrictions during the COVID-19 pandemic, induces oxidative stress through oxygen supply and antioxidant activity imbalance which in turn induce degenerative diseases. Salat dhuha as a prayer and mind-body medicine which is practiced by the Muslim community can hopefully be a solution to decrease oxidative stress in the elderly.

Objective

To evaluate the acute physiological effects of salat dhuha on Glutathione Peroxidase activity (GPx) as an antioxidant and Malondialdehyde (MDA) as an oxidant in healthy elderly Muslim women population who have done salat dhuha regularly.

Method

A randomized controlled study was done on elderly women (aged 60-74 years old) who are treated in the North Sumatra Government's Nursing Home in Binjai and who routinely do 2 rakaat of salat dhuha every day. Several physical, clinical, and blood examinations were done pre and post-intervention. 101 elderly Muslim women in the nursing home were selected, 26 met the study criteria and were included in the study. The volunteers were randomized into 2 groups using lottery papers, the "2-rakaat salat dhuha group" (n = 13) and the "8-rakaat salat dhuha group" (n = 13). All volunteers did salat dhuha for at least 5 days per week for 6 weeks.

Result

24 elderly women completed the study, and one volunteer from each group dropped out. The characteristics of participants from both groups were homogenous. Results of the t-independent analysis showed that MDA concentrations in both groups in the pre and post-test were not significantly different (p > 0,05). Mann Whitney analysis showed that GPx on both groups in the pre and post-test were not significantly different (p > 0,05). Paired sample t-test analysis on the MDA concentrations pre and post-test in the 8-rakaat group showed a significant difference in MDA levels (p < 0,05). The 8-rakaat salat dhuha group showed that GPx activity increases as much as 8,9% and MDA levels decrease as much as 48,35 % after 6 weeks.

Conclusion

Salat dhuha promotes redox homeostasis and has the potential to prevent oxidative stress in elderly women.

Analysis of contact pressure in a 3D model of dual-mobility hip joint prosthesis under a gait cycle

Hip joint prostheses are used to replace hip joint function in the human body. The latest dual-mobility hip joint prosthesis has an additional component of an outer liner that acts as a cover for the liner component. Research on the contact pressure generated on the latest model of a dual-mobility hip joint prosthesis under a gait cycle has never been done before. The model is made of ultrahigh molecular weight polyethylene (UHMWPE) on the inner liner and 316L stainless steel (SS 316L) on the outer liner and acetabular cup. Simulation modeling using the finite element method is considered static loading with an implicit solver for studying the geometric parameter design of dual-mobility hip joint prostheses. In this study, simulation modeling was carried out by applying varying inclination angles of 30°, 40°, 45°, 50°, 60°, and 70° to the acetabular cup component. Three-dimensional loads were placed on femoral head reference points with variations of femoral head diameter used at 22 mm, 28 mm, and 32 mm. The results in the inner surface of the inner liner, the outer surface of the outer liner, and the inner surface of the acetabular cup showed that the variations in inclination angle do not have a major effect on the maximum contact pressure value on the liner component, where the acetabular cup with an inclination angle of 45° can reduce contact pressure more than the other studied inclination angle variations. In addition, it was found that the 22 mm diameter of the femoral head increases the contact pressure. The use of a larger diameter femoral head with an acetabular cup configuration at a 45° inclination can minimize the risk of implant failure due to wear.

Effects of Interactive Dynamic Scalp Acupuncture on Motor Function and Gait of Lower Limbs after Stroke: A Multicenter, Randomized, Controlled Clinical Trial

OBJECTIVE

To evaluate the effects of interactive dynamic scalp acupuncture (IDSA), simple combination therapy (SCT), and traditional scalp acupuncture (TSA) on motor function and gait of the lower limbs in post-stroke hemiplegia patients.

METHODS

A total of 231 patients with post-stroke hemiplegia was randomly divided into IDSA (78 cases), SCT (78 cases), and TSA (75 cases) groups by a random number table. Scalp acupuncture (SA) and lower-limb robot training (LLRT) were both performed in the IDSA and SCT groups. The patients in the TSA group underwent SA and did not receive LLRT. The treatment was administered once daily and 6 times weekly for 8 continuous weeks, each session lasted for 30 min. The primary outcome measures included Fugl-Meyer assessment of the lower extremity (FMA-LE), berg balance scale (BBS), modified barthel index (MBI), and 6-min walking test (6MWT). The secondary outcome measures included stride frequency (SF), stride length (SL), stride width (SW), affected side foot angle (ASFA), passive range of motion (PROM) of the affected hip (PROM-H), knee (PROM-K) and ankle (PROM-A) joints. The patients were evaluated before treatment, at 1- and 2-month treatment, and 1-, and 2-month follow-up visits, respectively. Adverse events during 2-month treatment were observed.

RESULTS

Nineteen patients withdrew from the trial, with 8 in the IDSA and 5 in the SCT groups, 6 in the TSA group. The FMA-LE, BBS, 6MWT and MBI scores in the IDSA group were significantly increased after 8-week treatment and 2 follow-up visits compared with the SCT and TSA groups (P<0.05 or P<0.01). Compared with pre-treatment, the grade distribution of BBS and MBI scores in the 3 groups were significantly improved at 1, 2-month treatment and 2 follow-up visits (P<0.05 or P<0.01). The SF, PROM-H, PROM-K and PROM-A in the IDSA group was significantly increased compared with the SCT and TSA groups after 8-week of treatment (P<0.05 or P<0.01). Compared with the SCT group, ASFA of the IDSA group was significantly reduced after 8-week of treatment (P<0.05). SF, SL, PROM-K and PROM-A were significantly increased at the 2nd follow-up visit whereas the ASFA was significantly reduced in the IDSA group compared with the SCT groups at 1st follow-up visit (P<0.05 or P<0.01). The SF was significantly increased in the SCT group compared with the TSA group after 8-week treatment (P<0.05). Compared with the TSA group, PROM-K, PROM-A were significantly increased at the 2nd follow-up visit (P<0.05).

CONCLUSIONS

The effects of IDSA on lower-limb motor function and walking ability of post-stroke patients were superior to SCT and TSA. The SCT was comparable to TSA treatment, and appeared to be superior in improving the motion range of the lower extremities. (Registration No. ChiCTR1900027206).

Personalized Cup Positioning Guides Improved Cup Positioning and Hip Ranges of Motion in Robotic Assisted Total Hip Arthroplasty

Objective

Precise hip cup positioning is essential for the prevention of component impingement and dislocation in robotic assisted total hip arthroplasty (THA). Currently, the robotic system uses a mechanical alignment guide (MAG) for cup placement, which is one-size-fits-all, and the optimal cup positioning is controversial. Robotic assisted THA has not used any personalized cup positioning guides. The goal of this study was to identify an optimal guide for cup placement in robotic assisted THA to improve prognosis and life quality after THA.

Materials and Methods

Pelvis and femoral CT data of 47 participants were retrospectively collected for preoperative planning of robotic THA. The universal MAG guide and three personalized guides, including acetabular rim labrum guide (ARLG), transverse acetabular ligament guide (TALG), and ischiatic-pubis line guide (IPLG), were used to pose cups in the acetabulum of each participant. The position of cups was evaluated by inclination and anteversion; the function of hip joints was evaluated by hip ranges of motion, including abduction, adduction, extension, flexion, internal rotation, and external rotation.

Results

In terms of cup positioning, ARLG provided a bigger cup inclination (p < 0.0001), while IPLG and TALG provided smaller cup inclination (p < 0.001) than MAG; the three personalized guides provided larger cup anteversion (p < 0.0001) than MAG. In terms of HROMs, compared with the use of MAG, the use of three personalized guides significantly decreased abduction (p < 0.0001), extension (p < 0.0001), and external rotation (p < 0.0001), but increased significantly flexion (p < 0.0001) and internal rotation (p < 0.0001); the use of ARLG significantly reduced adduction (p < 0.0001), but the use of IPLG and TALG increased adduction (p < 0.0001).

Conclusion

Compared with MAG, personalized guides provided greater flexion and internal rotation, which may reduce the risk of posterior dislocation. Among the three personalized guides, IPLG is the most reliable one for the preoperative planning of robotic assisted THA.