Factors associated with physical activity following total knee arthroplasty for knee osteoarthritis: a longitudinal study.

BACKGROUND: After total knee arthroplasty (TKA), patients' physical activity (PA) levels at 6 months are lower than those of healthy subjects. Few studies have investigated the factors associated with PA at 6 months after TKA by objectively measuring preoperative and postoperative PA intensity using an accelerometer and knee function using a goniometer and dynamometer. The purpose of this study was to determine the factors associated with PA levels at 6 months after TKA based on objective data. METHODS: Eighty-two patients (mean [SD] age 74.5 [6.4] years) with moderate-to-severe knee osteoarthritis (OA) who were scheduled for TKA at the Nagoya Orthopaedic and Joint Replacement Clinic from July 2018 to July 2019 were enrolled in this longitudinal study. All patients underwent evaluations of knee function, including range-of-motion and knee-extension muscle strength; knee pain; performance in the timed up-and-go test; and accelerometer-measured PA both preoperatively and 6 months postoperatively. Factors associated with PA at 6 months after TKA were assessed using a hierarchical multiple linear regression analysis adjusted for age, sex, body mass index, and presence of diabetes mellitus. RESULTS: A higher average daily step count at 6 months after TKA was significantly associated with greater preoperative knee-extension muscle strength on the operated side (ß = 0.155, p = 0.028) as well as a higher preoperative average daily step count (ß = 0.834, p < 0.001). Furthermore, average daily time spent in moderate-to-vigorous-intensity PA postoperatively was significantly associated only with time spent in moderate-to-vigorous-intensity PA preoperatively (ß = 0.723, p < 0.001). CONCLUSION: These findings indicate that a higher preoperative daily step count and greater preoperative knee-extension muscle strength on the operated side may be associated with a higher daily step count at 6 months after TKA. Factors associated with PA differed by the PA intensity level. Rehabilitation and interventions for psychosocial factors before TKA beginning when mild knee OA first occurs are expected to lead to increased PA in TKA patients.

Effects of walking with a "draw-in maneuver" on the knee adduction moment and hip muscle activity.

[Purpose] To investigate the effect of performing a draw-in maneuver (DI) on knee adduction moment (KAM) and hip and trunk muscle activities while walking. [Participants and Methods] We included 30 healthy young adults (21.5 ± 0.6 years, 16 males and 14 females) in this study. We measured the KAM and lever arm while participants walked with either a normal gait or a DI gait. We also performed surface electromyography (EMG) of the hip and trunk muscles (i.e., internal oblique abdominal muscle [IO], external oblique abdominal muscle [EO], multifidus muscle [MF], and gluteus medius muscle [GM]). [Results] The 1st peak of the KAM was significantly lower when walking with a DI gait compared to when walking with a normal gait. The integrated EMG activity of the IO, EO, and GM during the 1st half of the stance phase, and of the IO and EO during the 2nd half of the stance phase was significantly higher during the DI than during normal gait. [Conclusion] Compared with a normal gait, a DI gait leads to a decrease in the 1st peak of the KAM as a result of the shorter lever arm, and an increase in the muscular activity of the GM, IO, and EO.

Disuse Atrophy Accompanied by Intramuscular Ectopic Adipogenesis in Vastus Medialis Muscle of Advanced Osteoarthritis Patients.

Muscle dysfunction is the most important modifiable mediating factor in primary osteoarthritis (OA) because properly contracting muscles are a key absorber of forces acting on a joint. However, the pathological features of disuse muscle atrophy in OA patients have been rarely studied. Vastus medialis muscles of 14 female patients with OA (age range, 69 to 86 years), largely immobile for 1 or more years, were obtained during arthroplastic surgery and analyzed histologically. These were compared with female patients without arthritis, two with patellar fracture and two with patellar subluxation. Areas occupied by myofibers and adipose tissue were quantified. Large numbers of myofibers were lost in the vastus medialis of OA patients. The loss of myofibers was a possible cause of the reduction in muscle strength of the operated on knee. These changes were significantly correlated with an increase in intramuscular ectopic adipose tissue, and not observed in knees of nonarthritic patients. Resident platelet-derived growth factor receptor α-positive mesenchymal progenitor cells contributed to ectopic adipogenesis in vastus medialis muscles of OA patients. The present study suggests that significant loss of myofibers and ectopic adipogenesis in vastus medialis muscles are common pathological features of advanced knee OA patients with long-term loss of mobility. These changes may be related to the loss of joint function in patients with knee OA.

Does the Q - H index show a stronger relationship than the H:Q ratio in regard to knee pain during daily activities in patients with knee osteoarthritis?

[Purpose] The purpose of this study was to elucidate the relationship between knee muscle strength and knee pain in activities of daily living, based on consideration of the difference between extension and flexion strength (Q - H) and the hamstring:quadriceps (H:Q) ratio in patients with knee osteoarthritis. [Subjects and Methods] The participants were 78 females with knee osteoarthritis, and a total of 133 knees that had not been treated surgically were the targets of this research. The legs were divided according to dominance. Isometric knee extension and flexion muscle strength and knee pain during activities of daily living were measured. The H:Q ratio (flexion/extension muscle strength) and the difference between extension and flexion strength, (extension muscle strength/weight) minus (flexion muscle strength/weight), that is, Q - H, were calculated. The correlation between these indices and the knee pain score during activities of daily living was investigated. [Results] Greater knee pain during activities of daily living was related to lower knee extension muscle strength and Q - H in both the dominant and nondominant legs. Knee flexion muscle strength and the H:Q ratio were not significantly correlated with knee pain during any activities of daily living. [Conclusion] Knee extension muscle strength and Q - H were found to be significantly correlated with knee pain during activities of daily living, whereas the H:Q ratio was not.

Influencing Factors on Independent Walking in Children With Lumbosacral Lipomas: A Retrospective Cohort Study Based on a 5-Year Untethering Series.

Background: Caregivers are deeply concerned about children achieving independent walking, and evidence-based rehabilitation support is beneficial. However, current research is confined to a single study on spina bifida aperta, leaving a gap in understanding the timing of independent walking for lumbosacral lipomas. Objectives: This study aimed to examine the factors influencing independent walking in children with lumbosacral lipomas. Design: Retrospective cohort study. Methods: This retrospective cohort study included 124 children who underwent untethering surgery for lumbosacral lipomas. The age (in months) at which the children walked independently was used as the primary endpoint, and potential influencing factors, including the type of spinal lipoma, extent of lipoma removal, magnetic resonance imaging features, congenital anomaly complications, urinary/defecation management requirements, foot/toe symptoms, and orthotic device fabrications were analyzed. Results: Multiple logistic regression analysis showed that the most significant influencing factor for delayed independent walking was the presence of systemic combined anomalies (adjusted odds ratio = 15.5, P < .001), while non-systemic malformations, such as suburethral cleft, had limited effects. A subgroup analysis of 94 patients without systemic combined anomalies showed that the presence of a malformed conus medullaris was significantly associated with delayed independent walking (P = .014). The median age of independent walking in children with Morota's classification type 2 was 14 months, which is 1 month later compared to other types, although this difference was not significant (P = .055). Conclusion: Our findings suggest that complications arising from systemic combined anomalies and the presence of malformed conus medullaris are influencing factors in delays in independent walking in children with untethered lumbosacral lipomas.

[Participant characteristics and intervention effects of a program to improve the physical function in community-dwelling frail elderly subjects].

AIM: To examine the intervention effects of a physical function improvement program for community-dwelling frail elderly subjects. METHODS: The subjects included 309 participants (108 males, 224 females) who took part in "Iki Iki Health Classes," an exercise training program for frail elderly individuals conducted over three years from April 2008 to March 2011. The average participant age was 75.4±5.8 years in the males and 74.6±5.6 years in the females. RESULTS: Many participants had bone and joint disease with hypertension. The proportion of those with a history of falls (49.0%) was high. Significant improvements from the program were seen in the motor function and in the total scores for the Kihon checklist, grip strength, standing on one leg, timed up-and-go test (TUG), 5-m walking time and 5-m walking maximum time, fear of falling (77.5→70.1%) and subjective health ("good/well good/usually," increased from 73.6% to 89.1%). A new care-needs certification was issued in 21.6% of the subjects during the period spanning to March 31, 2013. A logistic regression analysis revealed that the deterioration of subjective health was significantly related to the presence of risk factors for new care-needs certification (odds ratio and 95% confidence interval: 4.99 (1.04-23.9), p=0.04). CONCLUSIONS: These results suggest that the interventions used in the program to improve the physical function contributed to improving the subjects' mental and physical functions. We speculate that whether improvements in subjective health are linked to roles in normal life and/or social activity participation is important for care prevention.

Effect of diabetes mellitus on physical activity in patients with knee osteoarthritis: A cross-sectional study.

PURPOSE: Knee osteoarthritis (OA) may be comorbid with diabetes mellitus (DM), and physical activity is a recommended lifestyle strategy for both diseases. The present study investigated the physical activity differences by intensity between knee OA patients with or without DM, and evaluated if physical activity was associated with the presence of DM in knee OA patients. METHODS: A total of 183 patients (mean age 74.9 ± 6.4 years) with moderate-to-severe knee OA underwent evaluation of knee function (i.e., knee flexion/extension range-of-motion, knee-extension muscle strength, and knee pain), the timed up-and-go (TUG) test, and physical activity measurement using an accelerometer. Physical activity by intensity was compared between knee OA patients with and without DM. The association between physical activity, including knee function and the TUG test time, and DM was assessed. RESULTS: The 2 groups (with or without DM) did not differ significantly in knee OA severity or age. Compared to knee OA patients without DM, knee OA patients with DM had a significantly lower average daily step count (p < 0.001), and significantly shorter times spent performing light-intensity physical activity (LPA; p < 0.001) and moderate-to-vigorous-intensity physical activity (MVPA; p = 0.006). After adjusting for age, sex, and body mass index, we found that a lower average daily step count and shorter LPA time significantly correlated with DM (ß = -0.200, p = 0.006; ß = -0.216, p = 0.004, respectively) and a longer TUG test time (ß = -0.196, p = 0.014; ß = -0.208, p = 0.011, respectively). A shorter MVPA time significantly correlated with lower contralateral knee-extension muscle strength (ß = 0.187, p = 0.032). CONCLUSION: Knee OA patients with DM had significantly lower physical activity levels than those without DM. Furthermore, the presence of DM correlated with a lower step count and a shorter LPA time in knee OA patients.

Coupling reaction on gold nanoparticle to yield polythiophene/gold nanoparticle alternate network film.

The novel gold nanoparticle, which was stabilized with pi-conjugated molecules bearing functional groups at the terminals, was prepared via conventional procedure by using 5-bromo-2,2'-bithiophene-5'-thiol as a stabilizer. The gold nanoparticle (ca. 3 nm-diameter) showed good dispersion stability in various organic solvents, and its electrochemical and spectroscopic study revealed peculiar properties originated in the pi-conjugated molecular stabilizer, bithiophene derivative. The Pd-catalyzed coupling reaction on the gold nanoparticle was first achieved by using the gold nanoparticle bearing bromo groups at the particle surface and the model boronic acid molecule, 5-formyl-2-thiopheneboronic acid, to yield the terthiophene derivatives on the gold nanoparticle. The 1H-NMR, UV, and TGA analysis supported the progress of the coupling reaction on the gold nanoparticle. This Pd-catalyzed coupling reaction was applied with the borate-terminated polythiophene to form polythiophene/gold nanoparticle alternate network film. The electron microscopic images supported the formation of the network structure. The high electric conductivity on the network film suggested that the conductive characteristic of the film originated from that of the pi-conjugated polythiophene backbone connected with the gold nanoparticle.

Relationship between standing postural alignments and physical function among elderly women using day service centers in Japan.

BACKGROUND: Posture and physical function have been quantified in mature adults, but not in elderly females. OBJECTIVE: To quantify standing posture and measures of physical function in community-dwelling women over the age of 65 years, and to examine relationships between these variables. METHODS: Fifty-three women were recruited from day care service users (average age: 83.7 ±6.3 years old). Standing postural alignments were assessed using 2-dimensional analyses with a digital video camera. The time up and go test (TUG) and other physical function tests were conducted. RESULTS: Decreased lower cervical angle (increased forward head position) was significantly correlated with increased upper cervical angle (increased chin-up, r = −0.45), increased thoracic spine angle (increased kyphosis, r = −0.38), and decreased lumbar spine angle (thoracolumbar segments backward relative to the pelvis, r = 0.48). The decreased lumbar spine angle was significantly correlated with increased thoracic angle (increased kyphosis, r = −0.37), increased pelvic plane angle (increased anterior pelvic tilt, r = −0.49), and decreased knee flexion angle (r = 0.46). Increased TUG time (slower walking speed) was correlated to increased forward head position (r = 0.30) and thoracolumbar segments forward relative to the pelvis (r = 0.34). CONCLUSIONS: Posture and physical function measures were provided for community-dwelling females who were >65 years of age. They did not demonstrate any correlation between measured knee strength, back strength or single leg standing with measures of postural alignment, but TUG showed a moderate correlation with the lower cervical and lumbar spine posture measures.

Association of grip strength and related indices with independence of activities of daily living in older adults, investigated by a newly-developed grip strength measuring device.

AIM: To investigate the association of grip strength and activities of daily living independence in older adults, using a newly-developed grip strength measuring device. METHODS: Patients who visited the clinic for memory disorders at the National Center for Geriatrics and Gerontology (142 men and 205 women, mean age 74.8 ± 8.8 years) were included in the present study. Their strength during gripping performance is described in detail, and following the indices were calculated: maximum strength (MS), response time (RT), time to MS, time to reach turning point (TP), strength at TP, inclination from start to TP, time from TP to reach MS, inclination from TP to MS and ratio of strength (TP/MS). Barthel Index (BI), total scores and scores of each subclass were used for evaluating activities of daily living independence. MS was compared between the independent and dependent groups. Correlations, using partial Pearson's coefficient adjusted for age, and Mini-Mental State Examination total score were analyzed between indices and BI by sex, side, and age groups. RESULTS: MS was significantly higher in the independent group. MS and RT were significantly related with BI total and certain subclasses in both hands, TP/MS was significantly related in the right hand of either sex, and strength at TP was significantly related in both hands in women and in the left hand in men. Time to reach TP was particularly correlated in both hands and time from TP to reach MS in the right hand, in men. The correlation of indices varied by sex, hand side and age group, especially in men aged in their 70s, and in women aged less than 70 years and women aged in their 80s. CONCLUSION: MS was shown to be useful, but some of the newly defined indices, such as RT, strength at TP, and elements regarding before and after TP until reaching MS, were also suggested to be useful.