Effects of obesity on inpatient rehabilitation outcomes following total knee arthroplasty

Greater risk of all-cause revisions and complications for obese patients in 3 106 381 total knee arthroplasties: a meta-analysis and systematic review

BACKGROUND

Obesity is a major public health issue and has considerable implications on outcomes of total knee arthroplasty (TKA). However, there has been conflicting evidence and conclusions on the effects of obesity on TKA. This meta-analysis compares the outcomes, complications, and peri-operative parameters of TKA in the obese (body mass index [BMI] ≥ 30 kg/m² ) versus non-obese (BMI < 30 kg/m² ) population as well as subgroup analysis of morbidly obese (BMI ≥ 40 kg/m² ) versus non-obese population.

METHODS

A meta-analysis was conducted with a multi-database search according to PRISMA guidelines on 12 September 2019. Data from all published literature meeting inclusion criteria were extracted and analysed.

RESULTS

Ninety-one studies were included, consisting of 917 447 obese and 2 188 834 non-obese TKA. Obese patients had higher risk of all-cause revisions (odds ratio [OR] = 1.15, 95% CI: 1.08-1.24, p < 0.0001), all complications (OR = 1.21, 95% CI: 1.06-1.38, p = 0.004), deep infections (OR = 1.47, 95% CI: 1.27-1.69, p < 0.0001), superficial infections (OR = 1.59, 95% CI: 1.32-1.91, p < 0.0001), wound dehiscence (OR = 1.46, 95% CI: 1.24-1.72, p < 0.0001) and readmissions (OR = 1.21, 95% CI: 1.05-1.40, p = 0.009). Subgroup analysis of morbidly obese patients revealed greater risks of all-cause revisions (OR = 1.25, 95% CI: 1.10-1.43, p = 0.0009), deep infections (OR = 1.98, 95% CI: 1.05-3.75, p = 0.04), superficial infections (OR = 2.44, 95% CI: 2.08-2.88, p < 0.0001) and readmissions (OR = 1.33, 95% CI: 1.20-1.47, p < 0.0001). No analysis was performed on patient reported outcome measures due to heterogeneous reporting methods.

CONCLUSION

Obese and morbidly obese patients have higher risks of revisions and infections post TKA. Surgeons should counsel patients of these risks during the informed consenting process and adopt preventative strategies into clinical practice to reduce risks where possible. In conclusion, obesity is a significant, modifiable risk factor for increased complications following TKA.

The relationship between obesity and primary Total Knee Replacement: A scoping review of the literature

BACKGROUND

Primary Total Knee Replacement (TKR) is one of the most commonly performed elective orthopaedic procedures globally. Many patients undergoing this type of surgery are overweight or obese. In the UK, clinical commissioning groups have imposed arbitrary Body Mass Index (BMI) thresholds for TKR surgery. Many obese patients undergoing TKR believe they will lose weight following the procedure because of increased mobility.

AIM

This paper aims to present the findings of a scoping literature review about the relationship between obesity and primary TKR and to make recommendations for clinical practice, education and policy.

METHODS

A scoping literature review investigated the impact of BMI/body weight on the need for TKR, the impact of body weight and or BMI on patient outcomes following TKR, weight loss/gain following TKR and the implications of obesity on cost of TKR.

FINDINGS

Seventy-one papers were included in the review. Seven studies reported statistically significant associations between increased BMI/obesity with the need for TKR. Thirty of the studies reported worse outcomes for obese patients compared to non-obese comparisons. Forty of the studies reported no difference between obese and non-obese participants, including some where outcomes of obese patients were better than non-obese comparisons. Eight studies reported on changes to weight before and after TKR, three of the studies reporting a higher percentage losing weight than gaining weight and four studies reporting that obese patients gained weight. The 8th study reported that morbidly obese patients largely returned to their baseline BMI postoperatively.

CONCLUSION

The findings of the review challenge the legitimacy of setting BMI thresholds to control access to TKR surgery. There is an urgent need to develop evidence based approaches to support weight loss and weight management for this group of patients. Obese patients undergoing TKR should receive specific information regarding potential additional risks of complications and poorer outcomes. There is a need for health promotion regarding the association of being overweight/obese in young adulthood and developing osteoarthritis of the knee joints requiring TKR in middle and older age.

The test-retest reliability and concurrent validity of the five times sit to stand test and step test in older adults with total hip arthroplasty

PURPOSE

The aim of the study was to determine the test-retest reliability and concurrent validity of the five times sit to stand test (FTST) and step test (ST) in older adults with total hip arthroplasty (THA).

METHODS

A cross-sectional and prospective study was carried out with 32 unilateral total hip arthroplasty patients. FTST, ST, and Timed Up & Go Test were evaluated at the first evaluation session. The test-retest reliability was evaluated by performing two repetitions of the FTST and ST. Besides, the functional status of the patients was evaluated with the Harris Hip Score (HHS). The test-retest reliability of the FTST and ST were assessed by the intraclass correlation coefficient (ICC). In the concurrent validity analysis, the Pearson correlation coefficient was analyzed. In addition, the standard error of measurement (SEM₉₅) and minimal detectable change (MDC₉₅) values of the FTST and ST were also calculated.

RESULTS

The mean age of the participants was 75.4 ± 10.3 years. The ICC score of FTST, ST (right) and ST (left) were 0.987, 0.908 and 0.846, respectively. SEM₉₅ and MDC₉₅ values of the FTST were 1.05 and 2.91, respectively. FTST was correlated with both the HHS and TUG (r₁ = -0.522, r₂ = 0.730, p < 0.01). SEM₉₅ and MDC₉₅ values of the ST (right) were 0.37 and 1.02, respectively. SEM₉₅ and MDC₉₅ values of the ST (left) were 0.55 and 1.52, respectively. Also, ST (right) was only correlated with TUG (r = -0.654, p < 0.01). ST (right) were correlated with both the HHS and TUG (r₁ = 0.503, r₂ = -0.806, p < 0.01). The degree of correlations was strong.

CONCLUSION

The FTST and ST are valid and reliable performance tests in older adults with primary unilateral THA.

Reliability of 4-meter and 10-meter walk tests after lower extremity surgery

PURPOSE

To investigate the test-retest reliability of the 4-meter walk test (4 MWT) and 10-meter walk test (10 MWT) in patients undergoing lower extremity surgery during inpatient rehabilitation.

METHOD

In all, 102 patients with total hip arthroplasty (THA), total knee arthroplasty (TKA), lower extremity fracture (LEF) and soft tissue operation were recruited. Patients performed two 4 MWT and two 10 MWT trials on the same day. The same researcher performed all the measurements to avoid inter-rater variability.

RESULTS

The 4 MWT and 10 MWT were shown to have excellent test-retest reliability. The ICCs for the 4 MWT and 10 MWT were found as 0.94 and 0.95, respectively. The SEMs for the 4 MWT and 10 MWT were 2.0 and 5.5 seconds, respectively. The smallest real difference at the 95% confidence level (SRD95) was 5.5 seconds for the 4 MWT and 12.2 seconds for 10 MWT and SRD95 percentage was 31.2 for the 4 MWT and 28.5 for the 10 MWT.

CONCLUSION

Both the 4 MWT and the 10 MWT have excellent reliability in patients undergoing lower extremity surgery such as TKA, THA, LEF and soft tissue operation during inpatient rehabilitation. Clinicians and researchers can be confident that changes above the SRD95s for the different patient groups, for both sexes and with regard to weight-bearing status, represent a real clinical change in rehabilitation process. Implications for Rehabilitation The 4 MWT and the 10 MWT are simple methods and were also shown to be reliable measurement methods in many patient groups. This study illustrates that the test-retest reliability of the 4 MWT and 10 MWT are excellent in patients undergoing lower extremity surgery during inpatient rehabilitation (ICC: 0.94 for 4 MWT, ICC: 0.95 for 10 MWT). Clinicians and researchers can be confident that changes above the SRD95s for the different patient groups, for both sexes and with regard to weight-bearing status represent a real clinical change in rehabilitation process.

EVALUATION OF FUNCTIONAL CHARACTERISTICS IN PATIENTS WITH KNEE OSTEOARTHRITIS

OBJECTIVE

This study evaluated the physical and functional characteristics of Turkish patients with knee osteoarthritis and how this disease affects their physical and functional status.

METHODS

This study included 320 patients, who were evaluated to assess body mass index (BMI) and Hospital for Special Surgery (HSS) score in terms of age, sex and functional characteristics.

RESULTS

Mean patient age was 66.92±8.89 years and mean BMI was 31.02±5.20 kg/m². Mean patient HSS score was 58.70±11.08. According to their sit-to-stand test results, 33% of the patients (n=104) were found to be independent. There was a significant relationship between BMI and functional activity score (p<0.05).

CONCLUSIONS

The majority of the patients in our study were female and obese, and had low functionality levels. Function in patients with OA is restricted as a result of excess weight, so preventive measures can help Turkish patients with OA maintain their ideal weight. Furthermore, patient education can be help this population acquire the habit of regular exercise in order to reduce pain and improve their physical activity and quality of life. Level of Evidence IV, Case Series.

The Effect of Shoulder Flexion Angles on the Recruitment of Upper-extremity Muscles during Isometric Contraction

The purpose of this study was to investigate the differences in muscle activation patterns of the biceps brachii (BB) and flexor carpi radialis (FCR) muscles, while measuring the resultant force (RF) at different shoulder flexion angles. [Subjects] Thirteen healthy males (age 24.85±3.4 years, weight; 77.8±7.9 kg; height, 1.7±0.05 m) were enrolled in this study. [Methods] The resultant force was measured by a force transducer . The elbow angle remained constant and the flexion shoulder angle was changed (30°, 45°, 60°, 75° and 90°). [Results] The results of the surface EMG show the largest muscle activities occurred at a shoulder flexion of 75° for BB and 90° for FCR. The largest resultant force was measured at a shoulder flexion angle of 75°. We conclude, that when performing the biceps curl exercise using an arm curl machine, the shoulder should be flexed at 75° to maximize the focus of the exercise for the BB. [Conclusion] These results are useful from the perspective of design as they highlight the differences in the muscle activation of BB and FCR with postural change. Ultimately this knowledge can be used in the design of rehabilitation training for the shoulder as they show that posture can affect muscle activation.