Relationship between the Hip Abductor Muscles and Abduction Strength in Patients with Hip Osteoarthritis

This study aimed to determine which muscle the gluteus maximus, gluteus medius, gluteus minimus (Gmin), or tensor fasciae latae (TFL) contributes most to hip abduction strength and to identify effective sites for cross-sectional area (CSA) Gmin and TFL measurement in hip osteoarthritis (OAhip) patients. Twenty-eight patients with OAhip were included. The muscle CSA and volume were determined using magnetic resonance imaging. Peak isometric strength was determined using hand-held dynamometry. Muscle volumes were normalized to the total muscle volume of hip abductors. Multiple regression analysis was performed. The difference between the CSA of Gmin and TFL was calculated, and correlations with volume and muscle strength were determined. Gmin volume was related to abductor muscle strength (p=0.042). The peak CSA of the Gmin correlated with muscle volume and strength. The CSA of the TFL correlated with volume, with no difference between the CSA of the most protruding part of the lesser trochanter and peak CSA. Gmin volume was strongly related to abductor muscle strength. Peak CSA is a useful parameter for assessing the CSA of the Gmin among patients with OAhip. The CSA of the TFL should be measured at the most protruding part of the lesser trochanter

The Long-Term Efficacy of Computed Tomography-Navigated Total Hip Arthroplasty: An 18-Year Follow-Up Study

Backgroumd: There have been few reports on the long-term survival of computed tomography (CT)-navigated total hip arthroplasty (THA), which should lead to a lower incidence of dislocation and loosening. In this study, we examined survivorship, dislocation, and loosening incidence using plain radiographs over a minimum 15-year follow-up after CT-navigated THA.Methods: We retrospectively reviewed 145 consecutive CT-navigated THAs for >15 years. We surveyed the angles placed in both the acetabular and femoral components, survivorship, the occurrence of dislocation, the revision rate, and the fixation grade of the acetabular component. Results: The mean follow-up duration was 18.4 years. Overall, 73.8% of THAs were within the safe zone of Lewinnek. There were four dislocations (2.8%), with three occurring within 1 month after surgery and the other within 7 years after surgery. Revision THA was performed in one case (0.69%); consequently, the survival rate was 99.3%. The fixation grade was evaluated in 144 hips, and those were evaluated as having “no loosening”. Conclusions: CT-navigated THA was speculated to contribute to long-term survivorship, with a low rate of loosening, even after 18 years of follow-up. It was speculated that the acetabular component was placed at an acceptable insertion angle and a suitable position for stable initial fixation

Accuracy of ZedView, the Software for Three-Dimensional Measurement and Preoperative Planning: A Basic Study

Background and Objectives: In the field of orthopedic surgery, novel techniques of three-dimensional shape modeling using two-dimensional tomographic images are used for bone-shape measurements, preoperative planning in joint-replacement surgery, and postoperative evaluation. ZedView® (three-dimensional measurement instrument and preoperative-planning software) had previously been developed. Our group is also using ZedView® for preoperative planning and postoperative evaluation for more accurate implant placement and osteotomy. This study aimed to evaluate the measurement error in this software in comparison to a three-dimensional measuring instrument (3DMI) using human bones. Materials and Methods: The study was conducted using three bones from cadavers: the pelvic bone, femur, and tibia. Three markers were attached to each bone. Study 1: The bones with markers were fixed on the 3DMI. For each bone, the coordinates of the center point of the markers were measured, and the distances and angles between these three points were calculated and defined as “true values.” Study 2: The posterior surface of the femur was placed face down on the 3DMI, and the distances from the table to the center of each marker were measured and defined as “true values.” In each study, the same bone was imaged using computed tomography, measured with this software, and the measurement error from the corresponding “true values” was calculated. Results: Study 1: The mean diameter of the same marker using the 3DMI was 23.951 ± 0.055 mm. Comparisons between measurements using the 3DMI and this software revealed that the mean error in length was Conclusion: This surgical planning software could measure the distance and angle between the centers of the markers with high accuracy; therefore, this is very useful for pre- and postoperative evaluation

Determining factors that maintain physical function or increase frailty using the Kihon checklist among community-dwelling older adults: a six-year longitudinal study in Agano, Japan

Abstract Background A significant increase in the older adult population in Japan will significantly increase healthcare costs. This study aimed to examine the risk factors contributing to robustness transitioning to frailty in older residents. Methods Participants were aged 70 in 2016 and 76 in 2022. Participants were evaluated using the Kihon Checklist (KCL). Results Participants for this longitudinal study included 444 older persons who completed the KCL surveys in 2016 and 2022. The follow-up rate was 80.6%; therefore, 358 participants were included in the analysis. The median KCL score increased significantly from 2 to 2016 to 3 in 2022 (p < 0.001). The prevalence of robustness significantly decreased from 60.9 to 48.6% (p = 0.042). In a stepwise logistic regression analysis, robustness was independently associated with regular continuous walks for 15 min and a body mass index of above 18.5%. The following variables were associated with the transition to prefrailty: experiencing a fall in the past year and not going out at least once a week. For the transition to frailty, the variables were turned to family or friends for advice, experienced a fall in the past year, and felt helpless in the last two weeks. The independent factor for the transition from prefrailty to frailty was having a BMI of less than 18.5. In contrast, the independent factor for improving from frailty to robustness or prefrailty was going out at least once a week. Conclusions We recommend maintaining continuous walking for more than 15 min, maintaining a BMI of at least 18.5, and going out more than once a week to improve being house-bounded and depressive mood, not only to prevent the transition to prefrailty or frailty but also to improve frailty

Analysis of Phase Angle and Balance and Gait Functions in Pre-Frail Individuals: A Cross-Sectional Observational Study

We measured the muscle mass and phase angle of each body part to evaluate the relationship between balance and gait functions in individuals with a pre-frailty status. This cross-sectional observational study determined the skeletal muscle mass-to-body weight ratio and phase angles of 21 control (robust) and 29 pre-frail subjects. Their Brief-Balance Evaluation Systems Test, Timed Up-and-Go (TUG) test, Life-Space Assessment, and Modified Fall Efficacy Scale scores plus the relationship between muscle mass, phase angle, and motor function were evaluated. In the pre-frailty group (three males, 26 females, aged 75.58±7.60 years), significant correlations were noted between the Brief-Balance Evaluation Systems Test score and lower-limb (r=0.614) and wholebody (r=0.557) phase angles, and between the TUG test score and lower-limb muscle mass-to-body weight ratio (r=−0.616), lower-limb phase angle (r=−0.616), and whole-body phase angle (r=−0.527). Evaluating the phase angle of the lower extremities of pre-frail patients and intervening accordingly may help clinicians maintain and improve these patients’ balance and gait functions

Three-dimensional Evaluation of Abnormal Gait in Patients with Hip Osteoarthritis

Indexes for objectively evaluating abnormal gait in hip osteoarthritis (OA) patients and determining effective interventions are unclear. We analyzed the abnormal gait of hip OA patients by focusing on movements of the trunk and pelvis to establish an effective evaluation index for each direction of motion. We studied 28 patients with secondary hip OA due to developmental dysplasia of the hip and 16 controls. The trunk and pelvic movements during gait were measured in the medial-lateral (x), vertical (y), and back-and-forth (z) directions by a triaxial angular accelerometer. Gait speed, steps, step length, muscle strength, range of motion, and timed up-and-go (TUG) test performance were measured. We determined the correlations between physical function and the index of abnormal gait in the hip OA patients. Movements other than trunk and pelvic motions in the y-direction indicated abnormal gait in the patients. Significant correlations were found between abnormal gait and range of motions (extension, internal rotation), TUG score, stride length, and steps. The TUG test, stride length and steps were important for evaluating abnormal gait in hip OA patients. Individual interventions for each movement direction are required