Predictors of falls in patients during the first year after total hip arthroplasty: A prospective cohort study

Does self-reported physical activity relate to physical function and walking ability in female patients with hip osteoarthritis? A cross-sectional multicenter study

BACKGROUND

The effectiveness of a high level of physical activity in maintaining physical function in patients with hip osteoarthritis has not been adequately examined.

OBJECTIVE

This study aimed to determine whether self-reported physical activity is associated with physical function and walking ability in female patients with hip osteoarthritis.

METHODS

This was a multicenter cross-sectional study. The dependent variables were the lower-limb range of motion and muscle strength, and walking ability. Self-reported physical activity was assessed according to the guidelines of the Japanese Ministry of Health, Labor, and Welfare. Multiple regression models were used to determine whether physical activity was significantly related to the dependent variables after adjusting for confounding factors (age, body mass index, hip pain, comorbidity, and severity of hip osteoarthritis).

RESULTS

A total of 167 participants were included in the study. Physical activity was associated with muscle strength in hip flexion (affected/unaffected, β = 0.18/β = 0.16), abduction (β = 0.19/β = 0.26), knee extension (β = 0.22/β = 0.26), Timed Up-and-Go test (β = -0.16), and 5-m walking time test (β = -0.15).

CONCLUSION

In female patients with hip osteoarthritis, greater physical activity was associated with greater lower extremity muscle strength and walking ability.

Incidences and circumstances of falls among women following total hip arthroplasty on long-term follow-up

BACKGROUND

Patients who undergo total hip arthroplasty have an increased risk of falls during the first postoperative year. However, it is unclear whether patients after total hip arthroplasty will continue to be at high risk of falls more than 1 year postoperatively. To better understand whether the risk of falls changes after a 1-year period, we investigated the incidences and circumstances of falls in women patients for 5 years after total hip arthroplasty.

METHODS

This longitudinal prospective cohort study analyzed 65 women with severe hip osteoarthritis who underwent total hip arthroplasty. The incidences and circumstances of falls before total hip arthroplasty and at 1, 2, and 5 years postoperatively were investigated. We assessed the Harris Hip Score and evaluated hip pain and ambulatory ability using a self-administered questionnaire.

RESULTS

The incidences of at least one fall were 30.8%, 26.2%, 23.1%, and 30.8% before and 1, 2, and 5 years after surgery, respectively. Among the circumstances of falls from pre-surgery to 5 years post-surgery, there was a significant difference in the direction of falls; however, there were no significant differences in the location, time, cause, and type of injury. Most falls occurred indoors by tripping or loss of balance during the daytime. Among the participants who had falls almost half sustained injuries, and approximately 10% of falls resulted in fractures each year. Although self-reported hip pain, ambulation, and the Harris Hip Score significantly improved in women after total hip arthroplasty compared to pre-surgery, there was no significant difference in the incidences of falls from 1 to 5 years post-surgery.

CONCLUSION

Women who underwent total hip arthroplasty continued to have an increased risk of falls and fall-induced injuries for 5 years postoperatively. Preventive measures against falling to reduce fall-induced injuries in the long term are required for women after total hip arthroplasty.

Nutritional Factors Related to Muscle Weakness 1 Year after Total Hip Arthroplasty: A Case-Control Study

OBJECTIVES

Prolonged muscle weakness after total hip arthroplasty (THA) remains a problem. Despite increasing physical activity up to 3 years after surgery, muscle strength was decreased to 80-90% of the healthy side 2 years after THA. The objective of the present study was to identify the nutritional factors related to muscle weakness 1 year after THA.

METHODS

Persons who underwent THA were divided into 2 groups according to the cutoff point of knee extensor strength that represents functional limitation: a normal-strength group of 71 persons and a muscle weakness group of 91 persons. The investigators assessed lower limb isometric strength, the 10-m timed gait test, and daily intakes of energy and nutrients from preoperative to 1 year after THA. The differences in nutrient intakes between the 2 groups (normal-strength group and muscle weakness group) were examined by multiple logistic regression analysis.

RESULTS

There was a significant difference between the groups in energy intake. Daily protein intake was related to knee extension strength gain above the cutoff point 1 year after THA.

CONCLUSIONS AND IMPLICATIONS

The present study suggested that to prevent prolonged muscle weakness after THA, a sufficient protein intake as well as an exercise intervention may be needed even half a year or after.

A predictive model for hip abductor strength and knee extensor strength 12 months after total hip arthroplasty with an interaction term

Background

Identifying populations with poor muscle recovery after total hip arthroplasty (THA) is important for postoperative physical therapy. Preoperative muscle strength is a strong factor that determines postoperative muscle strength. However, this effect may depend on other factors. Thus, predictive models with interaction terms are important for accurately predicting postoperative muscle strength. This study aimed to develop a predictive model for lower muscle strength 12 months after THA which incorporates interaction terms.

Methods

Subjects were female patients with hip osteoarthritis who underwent unilateral THA. Patients with locomotor disorders, neurological disorders, or postoperative complications were excluded. Hip abductor and knee extensor strength were measured, and a generalized linear model approach with preoperative muscle strength, age, body weight, height, disease duration, physical activity, and leg extension as explanatory variables was used to identify factors that determine muscle strength 12 months after THA. Models with interaction terms between preoperative muscle strength and other explanatory variables were also examined.

Results

A total of 82 patients were analyzed. Preoperative muscle strength, age, body weight, physical activity, and disease duration were extracted as factors that significantly and independently determine hip abductor and knee extensor strength. The interaction term between preoperative muscle strength and age was identified as a factor that significantly determines knee extensor strength. Regression coefficients for preoperative knee extensor strength and postoperative muscle strength were significant when age was +1 SD, but not when age was -1 SD.

Conclusions

The predictive model demonstrated that lower muscle strength 12 months after THA is determined by preoperative muscle strength, age, weight, physical activity, disease duration, and preoperative muscle strength, with the effect of preoperative muscle strength on knee extensor strength being dependent on age. When predicting postoperative knee extensor strength using preoperative muscle strength, it is important to consider the effect of age.

Prevalence of frailty and associated factors among community-dwelling older adults after total hip arthroplasty

OBJECTIVE

To evaluate the prevalence of frailty and associated factors among community-dwelling older adults who have undergone total hip arthroplasty (THA).

MATERIALS AND METHODS

This study, which employed a cross-sectional, observational design, was conducted between April and November 2020. The participants were older adults (⩾65 years) who had undergone primary THA at the study hospital. Based on Fried's modified phenotype, frailty was stratified into 3 degrees according to the presence of 3 or more of the following components: weight loss, weakness, exhaustion, low activity level, and slow walking speed. Multinomial logistic regression was used to analyse the associations of frailty with its potential risk factors.

RESULTS

The data of 518 participants were analysed. The overall prevalence of frailty and prefrailty was 11.4% and 51.0%, respectively. The multinomial logistic regression analysis showed that calf circumference (odds ratio [OR] 0.716, 95% confidence interval [CI], 0.611-0.839; p < 0.001), fall history (OR 2.435, 95% CI, 1.114-5.322; p = 0.026), hip abductor muscle strength (OR 0.962, 95% CI, 0.938-0.987; p = 0.003), knee extensor muscle strength (OR 0.980, 95% CI, 0.964-0.996; p = 0.013), and Timed Up and Go test (TUG) performance (OR 1.802, 95% CI, 1.458-2.228; p < 0.001) were associated with frailty.

CONCLUSIONS

Frailty was highly prevalent in community-dwelling older adults after THA. Further, its potential associations with calf circumference, hip abductor and knee extensor muscle strength, TUG performance, and fall history highlight the significance of these factors for interventions.

Perioperative amino acid infusion reestablishes muscle net balance during total hip arthroplasty

Surgery and anesthesia induce a catabolic response that leads to skeletal muscle protein loss. Previous investigations have observed positive effects of perioperative nutrition. Furthermore, the benefits of exogenous amino acids on muscle protein kinetics are well established. However, no investigation has focused on muscle protein kinetics with and without perioperative amino acid infusion. Thus, we aimed to assess the effect of perioperative amino acid (AA) infusion on muscle protein balance in individuals undergoing elective total hip arthroplasty (THA). Elective THA patients were randomized to undergo a metabolic study prior to surgery (n = 5; control [CON]), intraoperative AA infusion (n = 9), or no AA (n = 13; standard of care [SC]). The CON group was studied prior to surgery to provide nonoperative/non-anesthesia muscle protein kinetic reference values. The bolus infusion method with 13 C6 -phenylalanine injected at time 0, and [15 N]-phenylalanine 30 min later was used to calculate muscle protein synthesis (MPS), protein breakdown (MPB), and net balance (MPS-MPB). Perioperative AA significantly improved muscle net balance as compared to SC (-0.005 ± 0.018%/h vs. -0.052 ± 0.011%/h) but not CON (0.003 ± 0.013%/h). The AA infusion significantly increased muscle net balance via a significant increase in MPS (AA = 0.062 ± 0.007%/h; SC = 0.037 ± 0.004%/h; CON = 0.072% ± 0.005%/h), and a nonsignificant attenuation of MPB (AA = 0.067 ± 0.012%/h; SC = 0.089 ± 0.014%/h; CON = 0.075 ± 0.011%/h). Our data support the use of perioperative AA infusion during elective THA as pragmatic strategy to offset the loss of surgically induced skeletal muscle protein.