Quality of life after total knee arthroplasty: systematic review

Predictors of health-related quality of life after total knee arthroplasty: a case-control study

Total knee arthroplasty (TKA) improves patients' Health-related quality of life (HRQoL) compared to before surgery. However, based on our knowledge, the improvement in HRQoL after TKA, which depends on various factors, has yet to be investigated compared to healthy people. This study aimed to evaluate the HRQoL of patients compared to healthy people and the factors affecting the HRQoL after TKA. In this matched case-control study (1002 participants), HRQoL in 501 patients who underwent TKA between 2015 and 2022 at Shafa Yahyainan Hospital affiliated with Iran University of Medical Sciences were compared with 501 healthy controls. HRQoL was evaluated in two parts (before compared to 12 months after TKA and 12 months after TKA compared to the healthy population). The 36-item short-form health survey (SF-36) was used to evaluate HRQoL 12 months after surgery. The influencing factors on HRQoL were evaluated by multivariate logistic regression analysis. No significant difference was observed in the demographic characteristics of the participants in the two groups. The mean overall SF-36 score, 12 months after surgery, significantly improved compared to before surgery (64.21 ± 22.2 vs. 37.55 ± 15.13, p:0.001). The mean total score of SF-36 was statistically similar between the case and control groups (64.21 ± 22.2 VS 72.53 ± 25.3). The multivariate analysis showed that sex, BMI, number of comorbidities, postoperative compliance, and complications were significantly related to the decrease in patients' HRQoL (P < 0.001).TKA can improve the HRQoL except for two subscales of happiness/vitality and physical performance, similar to the healthy population. Female gender, obesity and overweight, comorbidity, bilateral TKA, non-adherence to postoperative physiotherapy, and complications were associated with decreased HRQoL.

How effective is proximal fibular osteotomy in redistributing joint pressures? Insights from an HTO comparative in-silico study

BACKGROUND

Knee osteoarthritis (KOA) represents a widespread degenerative condition among adults that significantly affects quality of life. This study aims to elucidate the biomechanical implications of proximal fibular osteotomy (PFO), a proposed cost-effective and straightforward intervention for KOA, comparing its effects against traditional high tibial osteotomy (HTO) through in-silico analysis.

METHODS

Using medical imaging and finite element analysis (FEA), this research quantitatively evaluates the biomechanical outcomes of a simulated PFO procedure in patients with severe medial compartment genu-varum, who have undergone surgical correction with HTO. The study focused on evaluating changes in knee joint contact pressures, stress distribution, and anatomical positioning of the center of pressure (CoP). Three models are generated for each of the five patients investigated in this study, a preoperative original condition model, an in-silico PFO based on the same original condition data, and a reversed-engineered HTO in-silico model.

RESULTS

The novel contribution of this investigation is the quantitative analysis of the impact of PFO on the biomechanics of the knee joint. The results provide mechanical evidence that PFO can effectively redistribute and homogenize joint stresses, while also repositioning the CoP towards the center of the knee, similar to what is observed post HTO. The findings propose PFO as a potentially viable and simpler alternative to conventional surgical methods for managing severe KOA, specifically in patients with medial compartment genu-varum.

CONCLUSION

This research also marks the first application of FEA that may support one of the underlying biomechanical theories of PFO, providing a foundation for future clinical and in-silico studies.

High pain reported at 3 months post-total knee arthroplasty often persists for the next 3 years and is associated with reduced function and quality of life

BACKGROUND AND AIMS

Five to ten percent of people having a knee arthroplasty for osteoarthritis continue to experience high pain levels more than 3 months after surgery. The primary aim of this study was to determine the relative risk (RR) of having high pain at 12 and 36 months based on the presence of high pain at 3 and 12 months, respectively.

METHODS

A retrospective analysis of data from a prospective study of participants who had a total knee arthroplasty for osteoarthritis. A score of ≤14 on the Oxford Knee Pain Subscale was defined as 'High Pain', and RRs were calculated comparing those with high or low pain.

RESULTS

There were 718 participants and 13.8% reported high pain at any time point, 2.5% reported high pain at all time points and 10.3% and 4.7% and 6.6% reported high pain at 3-, 12- and 36-months, respectively, post-surgery. For participants with high pain at 3 months, 33.8% had high pain at 12 months with a RR of 24.2 (95% CI 11.7-49.8, p < 0.001) and 35.1% had high pain at 36 months with a RR of 10.8 (95% CI 6.4-18.2, p < 0.001). For participants with high pain at 12 months, 67.6% had high pain at 36 months, with a RR of 19.3 (95% CI 12.2-30.4, p < 0.01).

CONCLUSIONS

Although high pain rates are low overall following knee arthroplasty, once high pain is established there is an elevated RR of it persisting at 12- and 36 months post-surgery.

TRIAL REGISTRATION

The data were collected in the Evidence-based Processes and Outcomes of Care (EPOC) study, ClinicalTrials.gov Identifier: NCT01899443.

Factors Correlated with the Quality of Life after Total Knee Arthroplasties: A Literature Review

Introduction

Total Knee Arthroplasty (TKA) has been widely reported to improve outcomes and quality of life (QoL) in patients with knee osteoarthritis (KOA), but there are still 15 - 20% of patients still experience pain, physical limitations, and other complications after TKA. Therefore, it is necessary to identify various factors that correlate with QoL from current evidence. The objective is to review the literature on factors that correlate with QoL in patients who underwent TKA.

Materials and methods

A literature search was conducted on five databases, i.e. ProQuest, CINAHL, Medline, Embase, and Scopus, using the following keywords: total knee arthroplasty (TKA), post-operative, quality of life (QoL), and outcome. There were no restrictions on the research design.

Results

This review found 14 articles (7 prospective studies and 7 retrospective studies) involving 15,972 patients who underwent TKA, with an age range of 32 - 94 years. All articles reported improvement in QoL after TKA. The review revealed 30 factors, of which 15 factors were significantly correlated with QoL after TKA. The factors were grouped into four types: demographic, socioeconomic, clinical, and psychosocial factors.

Conclusion

Information regarding factors that correlate with QoL after TKA can be used for directing treatment and discharge planning according to the patient's factors.

A Study on Distinguishing ChatGPT-Generated and Human-Written Orthopaedic Abstracts by Reviewers: Decoding the Discrepancies

BACKGROUND

ChatGPT (OpenAI Incorporated, Mission District, San Francisco, United States) is an artificial intelligence (AI)-based language model that generates human-resembling texts. This AI-generated literary work is comprehensible and contextually relevant and it is really difficult to differentiate from human-written content. ChatGPT has risen in popularity lately and is widely utilized in scholarly manuscript drafting. The aim of this study is to identify if 1) human reviewers can differentiate between AI-generated and human-written abstracts and 2) AI detectors are currently reliable in detecting AI-generated abstracts.

METHODS

Seven blinded reviewers were asked to read 21 abstracts and differentiate which were AI-generated and which were human-written. The first group consisted of three orthopaedic residents with limited research experience (OR). The second group included three orthopaedic professors with extensive research experience (OP). The seventh reviewer was a non-orthopaedic doctor and acted as a control in terms of expertise. All abstracts were scanned by a plagiarism detector program. The performance of detecting AI-generated abstracts of two different AI detectors was also analyzed. A structured interview was conducted at the end of the survey in order to evaluate the decision-making process utilized by each reviewer.

RESULTS

The OR group managed to identify correctly 34.9% of the abstracts' authorship and the OP group 31.7%. The non-orthopaedic control identified correctly 76.2%. All AI-generated abstracts were 100% unique (0% plagiarism). The first AI detector managed to identify correctly only 9/21 (42.9%) of the abstracts' authors, whereas the second AI detector identified 14/21 (66.6%).

CONCLUSION

Inability to correctly identify AI-generated context poses a significant scientific risk as "false" abstracts can end up in scientific conferences or publications. Neither expertise nor research background was shown to have any meaningful impact on the predictive outcome. Focus on statistical data presentation may help the differentiation process. Further research is warranted in order to highlight which elements could help reveal an AI-generated abstract.

Relationships of cross-sectional area of the thigh muscles before or after total knee arthroplasty with postoperative pain or patient satisfaction: A retrospective, exploratory study

Background

It has been suggested that lower limb strength related to persistent postsurgical pain. The aim of the present study was to investigate the relationships of pre-operative or postoperative cross-sectional area (CSA) of the thigh muscles with knee pain or patient satisfaction after total knee arthroplasty (TKA).

Methods

Twenty patients who had undergone TKA (3 men and 17 women; mean age 75.2 ± 8.7 years) were included. CSAs of the thigh muscle (THIGH) and quadriceps muscle (QUAD) were retrospectively measured at the CT slice 10-cm superior to the quadriceps tendon insertion at the proximal pole of the patella. THIGH CSA and QUAD CSA to body weight ratios (mm2/kg), THIGH/W and QUAD/W ratios, respectively, were calculated. Knee pain and patient satisfaction postoperatively were also quantified by patient-reported measurements based on the 2011 Knee Society Score (KSS). The correlations between the THIGH/W and QUAD/W ratios and the KSS were evaluated using Spearman's rank correlation coefficient.

Results

The preoperative THIGH/W ratio was positively correlated with KSS-pain, (r = 0.58, p < 0.05). The preoperative QUAD/W ratio was positively correlated with KSS-pain (r = 0.52, p < 0.05) and KSS-satisfaction (r = 0.44, p < 0.05). The postoperative THIGH/W ratio was positively correlated with KSS-pain (r = 0.45, p < 0.05). The postoperative QUAD/W ratio was positively correlated with KSS-pain (r = 0.49, p < 0.05) and KSS-satisfaction (r = 0.48, p < 0.05).

Conclusion

There were significant correlations between quadriceps or thigh muscle CSA and pain or patient satisfaction after TKA. This research may help relieve pain and increase patient satisfaction after TKA in the future.

Knee Loading With Blood Flow Restriction Can Enhance Recovery After Total Knee Arthroplasty

Total knee arthroplasty (TKA) is one of the most performed operations in the world, especially in the elderly. Aging has a significant effect on joint cartilage, muscle strength, and muscle mass. Following a TKA, despite the significant reduction of symptoms and the improvement in mobility, muscle strength and muscle mass recovery remains a significant challenge. Restrictions that arise from the surgical procedure include joint loading, functional activities, and range of motion, along with limitations related to the age of the individual and their previous loading history, these are the significant restrictions, at least in the early stages of rehabilitation. Evidence indicates that blood flow restriction (BFR) training has significant potential to enhance recovery via implementation of low-load or low-intensity exercise. While respecting the indications and contraindications related to BFR application, the optimization of metabolic stress seems to offer a bridging therapy to heavy load while reducing pain and inflammation. Thus, the combination of BFR and low loads may improve muscular recovery (strength and mass), and aerobic training protocols appear to show significant enhancement of multiple cardiopulmonary parameters. Mounting evidence, direct and indirect, indicate that BFR training may have the potential to benefit the pre-operative and post-operative TKA rehabilitation phases and enhance functional recovery and physical abilities in the elderly.

[Knee flexion after hospitalisation is no predictor for functional outcome one year after total knee arthroplasty]

OBJECTIVE

In total knee arthroplasty (TKA), range of motion has become established as an important factor. The criterion of quality is set to flexion of 90° after hospitalisation. Currently, it is supposed to be a predictor for 1‑year postoperative outcome. However, as this correlation has not been proven, this clinical trial was performed.

METHODS

A total of 182 TKA recipients were analysed retrospectively. Outcomes were assessed before surgery, after hospitalization, 6 weeks and 1 year post surgery. They included knee range of motion (ROM) to answer the main hypothesis, but also KSS, SF-36, WOMAC, EQ-5D and VAS to evaluate knee function and quality of life. The patients were divided into two groups differing in achieving 90° flexion after hospitalisation and compared 6 weeks and 1 year after surgery.

RESULTS

Knee flexion differed significantly between groups from 91 to 70° in the group without the aim of 90° flexion after hospitalisation (E) (p < 0.001). After 6 weeks, flexion was improved to 112° ± 13° (E > 90°) vs. 106° ± 14° (E < 90°; p = 0.001). One year post surgery, knee flexion averaged 122° ± 10° (E > 90°) vs. 120° ± 10° (E < 90°) with no difference between the groups (p = 0.57) and no significant difference in all other scores concerning knee function and quality of life.

CONCLUSION

Flexion of 90° after hospitalisation is not adequate to predict medium-term outcomes after TKA. There is no advantage or disadvantage regarding whether the aim of 90° flexion is achieved.

Patient-Reported Outcome on Quality of Life and Pain after Revision Arthroplasty for Periprosthetic Joint Infection: A Cross-Sectional Study

This study aims to explore the quality of life (QOL) and pain after revision surgery for periprosthetic joint infection (PJI) based on patients' reported outcomes. A cross-sectional questionnaire survey was conducted and 137 valid responses were included (response rate 64.0%). A total of 42 patients underwent debridement with implant retention (DAIR), 31 underwent one-stage revision, and 64 underwent two-stage revision. The average overall SF-36 score was 70.3. The DAIR group had significantly higher SF-36 than the two-stage revision group (p = 0.01). There was no significant difference between the one-stage revision group and the other two groups. A total of 74.5% of patients reported pain with an average McGill Pain Questionnaire (MPQ) score of 8.6. There was no significant difference in the MPQ scores among the three groups. Simple linear regression analyses demonstrated that higher preoperative PMN%, VAS, and shorter hospital stay were associated with pain (adjusted R² = 4%, p = 0.020; adjusted R² = 2.1%, p = 0.048; adjusted R² = 2.1%, p = 0.049; respectively). We concluded that the overall QOL of patients after revision surgery for PJI is generally satisfactory. Persistent pain is prevalent, but the severity was mostly mild. Preoperative PMN%, VAS, and hospital stay were associated with postoperative pain.

Goals, challenges and strategies for wound and bleeding management in total knee arthroplasty: A modified Delphi method

BACKGROUND

Surgical techniques related to soft tissue management play critical roles in optimizing surgical outcomes and patient satisfaction in total knee arthroplasty (TKA). Despite the importance of wound closure and bleeding management approaches, no published guidelines/consensus are available.

METHODS

Twelve orthopedic surgeons participated in a modified Delphi panel consisting of 2 parts (each part comprising two rounds) from September-October 2018. Questionnaires were developed based on published evidence and guidelines on surgical techniques/materials. Questionnaires were administered via email (Round 1) or at a face-to-face meeting (subsequent rounds). Panelists ranked their agreement with each statement on a five-point Likert scale. Consensus was achieved if ≥70% of panelists selected 4/5, or 1/2. Statements not reaching consensus in Round 1 were discussed and repeated or modified in Round 2. Statements not reaching consensus in Round 2 were excluded from the final consensus framework.

RESULTS

Consensus was reached on 13 goals of wound management. Panelists agreed on 38 challenges and 71 strategies addressing surgical techniques or wound closure materials for each tissue layer, and management strategies for blood loss reduction or deep vein thrombosis prophylaxis in TKA. Statements on closure of capsular and skin layers, wound irrigation, dressings and drains required repeat voting or modification to reach consensus.

CONCLUSION

Consensus from Asia-Pacific TKA experts highlights the importance of wound management in optimizing TKA outcomes. The consensus framework provides a basis for future research, guidance to reduce variability in patient outcomes, and can help inform recommendations for wound management in TKA.

Association between VTE and antibiotic prophylaxis guideline compliance and patient-reported outcomes after total hip and knee arthroplasty: an observational study

BACKGROUND

Surgical site infection (SSI) and venous thromboembolism (VTE) are associated with high burden and cost and are considered largely preventable following total knee or hip arthroplasty (TKA, THA). The risk of developing VTE and SSI is reduced when prophylaxis is compliant with evidence-based clinical guidelines. However, the association between VTE and antibiotic prophylaxis clinical guideline compliance and patient-reported outcome measures (PROMs) after THA/TKA is unknown. This study aims to explore whether care that is non-compliant with VTE and antibiotic guideline recommendations is associated with PROMs (Oxford Hip/Knee Score and EQ-5D Index scores) at 90- and 365-days after surgery.

METHODS

This prospective observational study included high-volume arthroplasty public and private sites and consenting eligible participants undergoing elective primary THA/TKA. We conducted multiple linear regression and linear mixed-effects modelling to explore the associations between non-compliance with VTE and antibiotic guidelines, and PROMs.

RESULTS

The sample included 1838 participants. Compliance with VTE and antibiotic guidelines was 35% and 13.2% respectively. In adjusted modelling, non-compliance with VTE guidelines was not associated with 90-day Oxford score (β = - 0.54, standard error [SE] = 0.34, p = 0.112) but was significantly associated with lower (worse) 365-day Oxford score (β = - 0.76, SE = 0.29, p = 0.009), lower EQ-5D Index scores at 90- (β = - 0.02 SE = 0.008, p = 0.011) and 365-days (β = - 0.03, SE = 0.008, p = 0.002).. The changes in Oxford and EQ-5D Index scores were not clinically important. Noncompliance with antibiotic guidelines was not associated with either PROM at 90- (Oxford: β = - 0.45, standard error [SE] = 0.47, p = 0.341; EQ-5D: β = - 0.001, SE = 0.011, p = 0.891) or 365-days (Oxford score: β = - 0.06, SE = 0.41, p = 0.880 EQ-5D: β = - 0.010, SE = 0.012, p = 0.383). Results were consistent when complications were included in the model and in linear mixed-effects modelling with the insurance sector as a random effect.

CONCLUSIONS

Non-compliance with VTE prophylaxis guidelines, but not antibiotic guidelines, is associated with statistically significant but not clinically meaningful differences in Oxford scores and EQ-5D Index scores at 365 days.

Quality of life assessment after total knee arthroplasty in patients with Parkinson's disease

Background

The number of Parkinson’s patients (PD) undergoing total knee arthroplasty (TKA) is increasing. The purpose of the study was to characterize quality of life (QOL) outcomes for patients with coexisting PD and knee osteoarthritis (KOA) following TKA.

Methods

Patients with coexisting PD and KOA undergoing TKA between June 2014 and June 2020 were included. These patients were matched to controls with KOA alone by age, gender, basic social background information and Knee society score (KSS). The primary measure was to assess the QOL by the absolute changes in the EuroQOL5-Dimensions (EQ-5D), Pain and Disability Questionnaire (PDQ), and Patient Health Questionnaire-9(PHQ-9) at the last follow-up (LFU). Secondary measures were changes in QOL that exceeded the minimum clinically important difference value (MCID). Data on the health status and QOL of all patients were collected. Simple and multivariate regression analysis was used to evaluate the impact of PD on their QOL.

Results

Twelve KOA patients with PD were compared with 48 controls. Control patients experienced QOL improvement across all three measures:EQ-5D index (0.545–0.717, P < 0.01), PDQ (81.1–52.3, P < 0.01) and PHQ-9(8.22–5.91, P < 0.01) were significantly improved at the LFU; while in patients with PD, only PDQ (91.0–81.4, P = 0.03) slightly improved. There were significant differences in the improvement of QOL between PD patients and the control group through EQ-5D (0.531 vs.0.717, P < 0.01) and PDQ (81.4vs.52.3, P < 0.01) at the LFU.

Conclusion

TKA has no benefit of QOL beyond a slight improvement in pain-related disability in the KOA patients with PD.

Acute pain after total hip and knee arthroplasty does not affect chronic pain during the first postoperative year: observational cohort study of 389 patients

Chronic pain is frequently reported after total hip and knee arthroplasties (THA/TKA) in osteoarthritis (OA) patients. We investigated if severity of acute postoperative pain following THA/TKA in OA patients was associated with pain during the first postoperative year. From an observational study, OA patients scheduled for primary THA/TKA (June 2012–December 2017) were included from two hospitals in the Netherlands. Acute postoperative pain scores were collected within 72 h postoperatively and categorized as no/mild (NRS ≤ 4) or moderate/severe (NRS > 4). Pain was assessed preoperatively, 3, 6 and 12 months postoperatively using the HOOS/KOOS subscale pain. With Multilevel Mixed-effects-analyses, we estimated associations between acute and chronic pain until one year postoperative, adjusted for confounders and including an interaction term (Time*Acute pain). 193 THA and 196 TKA patients were included, 29% of THA and 51% of TKA patients reported moderate/severe pain acutely after surgery. In the THA group, the difference in pain at 3 months between the no/mild and moderate/severe groups, was approximately six points, in favor of the no/mild group (95% CI [−12.4 to 0.9]) this difference became smaller over time. In the TKA group we found similar differences, with approximately four points (95% CI [−9.6 to 1.3]) difference between the no/mild and moderate/severe group at 6 months, this difference attenuated at 12 months. No association between severity of acute postoperative pain and pain during the first postoperative year was found. These findings suggest that measures to limit acute postoperative pain will likely not impact development of chronic pain.

Recovery patterns in patients undergoing revision surgery of the primary knee prosthesis

Purpose

Despite good survival rates of revised knee prostheses, little is known about recovery trajectories within the first 12 months after surgery. This retrospective observational study explored recovery trajectories in terms of pain, function and quality of life in patients after revision knee arthroplasty over 12 months.

Methods

Eighty-eight revision knee arthroplasty patients rated changes in daily physical functioning using the anchor question (0: very much worsened; 7: very much improved). Patient reported outcome measures (PROMs) of pain (range 0–10), function (Oxford Knee Score) and quality of life (EQ-5D-3L) were assessed preoperatively, at 3 and 12 months postoperatively. Four recovery trajectories were identified using the anchor question at 3 and 12 months postoperatively: no improvement, late improvement, early improvement, and prolonged improvement. Repeated measures ANOVA was conducted with recovery trajectories as dependent variable and PROM assessments as independent variables.

Results

Sixty percent reported improvement in daily physical functioning at 12 months postoperatively. Age and reason for revision differed between groups. Pain, function and EQ-5D-3L differed between groups over time. Late and prolonged improvement groups improved on all PROMs at 12 months. The early improvement group did not report improvement in daily physical functioning at 12 months, while improvements in function and pain during activity were observed.

Conclusions

Different recovery trajectories seem to exist and mostly match PROMs scores over time. Not all patients may experience beneficial outcome of revision knee arthroplasty. These findings are of importance to provide appropriate information on possible recovery trajectories after revision knee arthroplasty to patients.

Level of evidence

III

Supplementary Information

The online version contains supplementary material available at 10.1186/s40634-021-00436-w.

Health-Related Quality of Life and Outcome after Total Knee Replacement: Results from a Cross-Sectional Survey in Jordan

Total knee replacement (TKR) is a common procedure that is considered cost-effective with excellent long-term survivorship. This cross-sectional study, which includes 118 selected patients in Jordan from January 2020 to January 2021, aims to assess health-related quality of life (HQOL), functional status, and associated factors before and after 3 to 12 months of TKR. Furthermore, several demographical factors were included in this study to evaluate the potential association with the procedure's outcome. Western Ontario and McMaster Universities Osteoarthritis Index scale (WOMAC) and Short Form-36 (SF-36) scale were used in this study. It was found that the main change occurred 6–12 months after the procedure. Gender and age were found to be the primary predictor of quality of life among TKR patients. Patients before the TKR procedure experienced severe pain, joint stiffness, physical impairment, and psychological demand issues. After the TKR procedure, all symptoms were improved significantly. The TKR procedure can improve the quality of life for patients, which can be detected for several months after the procedure. Function and pain are the most critical indicators of improvement in quality of life. Assessing the quality of life is a key indicator for identifying patients without improvement, as well as improving the health care process and comparing other alternative interventions.

Evaluation and Management of a Painful Knee After Total Knee Arthroplasty

Pain after total knee arthroplasty (TKA) is not infrequent and may be indicative of a broad spectrum of prosthesis-related, intra-articular, or extra-articular pathologies. To diagnose and treat the underlying cause of a painful TKA, systematic evaluation of the patient is critical to ensure that they are managed appropriately and expeditiously. This evidence-based review presents current concepts regarding the pathophysiology, etiology, and diagnosis of painful TKA and our recommended approach for management. [Orthopedics. 2021;44(6):341-352.].

Evaluation of wound healing in patients with hip prosthesis according to nursing outcome classification

PURPOSE

The purpose of this study is to perform Turkish adaptation and validation of NOC (1102) Wound Healing: Primary Intent and examine wound healing in patients with hip prosthesis diagnosed with impaired tissue integrity.

METHOD

The study was carried out in methodological and descriptive design, and the sample of the study consisted of 55 patients. Introductory Characteristics Form and Wound Healing: Primary Intention NOC Form were used for data collection. Ethical consent was obtained before initiating the study.

FINDINGS

In the study, content validity index value of the NOC scale was calculated was 95.71%. Looking at NOC scale indicators for postoperative day 1, 2, and 7 and the distribution of the total mean scores, it was determined that there was a statistically significant difference between the mean scores over time (p = 0.000). It was found that patients with chronic disease had lower NOC scale scores and wound healing was slower on the postoperative first day compared to the patients with no chronic diseases (p < 0.05).

CONCLUSIONS

As a result of the study, it was concluded that the Turkish version of the Wound Healing: Primary Intention NOC (1102) scale was a valid tool for evaluating the location of the wound in patients with hip prosthesis, the presence of chronic diseases affected wound healing, and mean scores obtained by the patients in NOC scale increased over time with a good progress in terms of wound healing.

IMPLICATIONS OF NURSING PRACTICE

With the use of Wound Healing: Primary Intention NOC (1102) scale, a common language will be formed in the evaluation of the wound site of patients undergoing hip prosthesis.

The impact of self-efficacy for physical activity on health-related quality of life in total knee arthroplasty recipients

BACKGROUND

Some patients with end-stage osteoarthritis of the knee remain unsatisfied after total knee arthroplasty (TKA). We postulated that to increase satisfaction, self-efficacy (SE) for physical activity should receive more attention in rehabilitative intervention, alongside the management of patient expectations, pain, and function.

OBJECTIVE

We examined the relative impact of Physical Activity SE on Health-Related Quality of Life (HRQOL) alongside other factors such as pain and physical function which are well-addressed by current interventions.

METHODS

One hundred and six first-TKA recipients (15 Male/91 Female, age 73.6 ± 7.2) were evaluated at 3 and 6 months post-operatively using the Medical Outcomes Study 36-Item Health Survey (SF-36v2) for HRQOL, knee extension strength measurement, Timed Up and Go test (TUG), One Leg Standing time test (OLS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) for pain and function, and an instrument for measuring Physical Activity SE among the frail elderly in Japan.

RESULTS

Significant improvement over pre-operative values was found at 3 and 6 months in TUG, OLS, WOMAC Pain and Function, and the 8 subscales of the SF-36v2. Factors found to significantly impact SF-36v2 subscale scores at 6 months post-operatively were found to be knee pain, knee function, and SE for physical activity.

CONCLUSION

These results support our postulation that interventions to improve SE for physical activity could have comparable impact alongside interventions for knee pain and knee function, on the advancement of HRQOL among TKA recipients.

A Qualitative Study of Patient Themes for the Quality of the Total Joint Arthroplasty Experience

Patients have limited involvement in the development of quality measures that address the experience of undergoing total joint arthroplasty (TJA). Current quality measures may not fully assess the aspects of care that are important to patients. The goal of this study was to understand quality of care in TJA from the patient perspective by exploring patients' knowledge gaps, experiences, and goals. The authors completed a prospective qualitative analysis of patients who had undergone hip or knee TJA. Patients completed an open-ended, structured questionnaire about the surgical and recovery process as it relates to quality of care. The authors used a phenomenologic approach and purposeful sampling to enroll 74 patients 6 to 8 weeks after TJA. Responses underwent thematic analysis. Codes were used to identify themes that were important to patients in quality of care in TJA. The authors identified 3 themes: (1) returning to activity without pain or complication, which included psychological, functional, and complication-related goals; (2) negotiating the physical and psychological challenges of recovery, which encompassed the need for assistance from the caregiver as well as psychological and physical barriers to recovery; and (3) being prepared and informed for the process of surgery, including physical, logistical, and psychological preparation. Both patients and health systems may benefit from efforts to address these patient-centered themes of quality care through quality measures for TJA (eg, improving the psychological challenges of recovery). Future quality measures, such as assessment of patient experience, may be made more patient centered if they measure and improve aspects of care that matter to patients. [Orthopedics. 2021;44(2):117-122.].

Evaluation of Disease Severity and Health-Related Quality of Life in Patients with Rheumatoid Arthritis Undergoing Total Knee Arthroplasty

;Background: The Total Knee Arthroplasty (TKA) is one of the most common surgical intervention in patients with osteoarthritis (OA) and rheumatoid arthritis (RA). Previous studies suggested a significant improvement in health status after TKA surgery. But we have little data about the Iranian population undergone TKA. In the current clinical study, we evaluated postoperatively health status using reliable tools of MOS SF-36 and WOMAC in OA and RA patients undergoing TKA.

METHODS

In this cohort study, patients with OA and/or RA who were candidates for TKA surgery were included. Using two reliable questionnaires, i.e., WOMAC and SF-36, the quality of life of patients was examined during a period of six months (three monthly intervals) after the surgery. All data were analyzed using IBM SPSS Statistics. Kolmogrov-Smirnov, Kendall's tau, chi-square test and K-related Non-parametric tests were used.

RESULTS

Of the 2126 patients who underwent TKA, there were 2024 diagnosed osteoarthritis and 102 validated RA over one year. The mean ± SD of age and the average BMI were 68.0 ± 7.0 BMI 28.5 kg/m2, respectively. Regarding comorbidities and concurrent disorders, about 14% of cases were diabetic, 42% had cardiovascular diseases, 3% had respiratory diseases, and 12% involved with gastrointestinal diseases. The result of SF-36 dramatically increased during follow up. The central distributions of all domains in the SF-36 questionnaire indicated that most scores increased during the time after surgery. As a consequence, WOMAC and MOS FS-36 indicated statistically significant changes after TKA for those who are suffering from RA or OA.

CONCLUSION

TKA is an effective surgical process, which improves the quality of life in OA and/or RA. In addition, WOMAC and SF-36 examining tools are likely reliable tools with similar results to assess patients' quality of life after TKA surgery.

Physical rehabilitation versus no physical rehabilitation after total hip and knee arthroplasties: Protocol for a pragmatic, randomized, controlled, superiority trial (The DRAW1 trial)

Background: Following total hip- and knee arthroplasty (THA and TKA), post-discharge physical rehabilitation is common practice, but varies significantly regarding content, duration, intensity and mode of delivery. Recent systematic reviews have found home-based rehabilitation to be as good as outpatient rehabilitation in terms of pain and physical function. We therefore wonder if physical rehabilitation "works" at all when compared to no physical rehabilitation after THA and TKA - "no rehabilitation" defined as no prescribed therapeutic rehabilitation exercises. The purpose of this trial is to compare the effectiveness of home-based telerehabilitation, home-based rehabilitation and no physical rehabilitation following THA and TKA.  Methods: This pragmatic, randomized controlled trial will include 168 patients following discharge after THA or TKA, in Bornholm Denmark. Patients will be randomized into one of the three 6-week rehabilitation strategies: home-based telerehabilitation, home-based rehabilitation or no physical rehabilitation. The trial is designed as a superiority trial to test the hypothesis that rehabilitation (home-based telerehabilitation and home-based rehabilitation) is superior to no physical rehabilitation. The primary outcome will be the hip disability and osteoarthritis outcome score (HOOS)/ the knee injury and osteoarthritis outcome score (KOOS)-subscale: function of daily living at first follow-up (end of the 6-weeks' intervention). Additional follow-ups are scheduled at 3 and 12 months. Outcome assessors and data analysts are blinded to group allocation. Conclusions: Knowledge about the effectiveness of the three investigated rehabilitation strategies will help guide the future organization of post-discharge rehabilitation after THA and TKA. Trial registration: Clinicaltrials.gov NCT03750448 (23/11/2018).

Mid-term survivorship and clinical outcomes of the medial stabilized systems in primary total knee arthroplasty: A systematic review

Introduction

Medial Pivot Total Knee Arthroplasty was introduced in clinical practice in 1990s to reproduce the in vivo-natural knee kinematics. This design is characterized by an asymmetric constraint profile, with aa highly congruent medial compartment, and a less congruent lateral compartment. Short-term outcomes of the medial pivot systems in primary knee arthroplasty have been widely reported in the current literature, however, only few studies have described results beyond 5-year follow-up.

Objectives

The primary objectives of this systematic review of the literature is to analyze the mid-term studies on medial pivot total knee arthroplasty focusing on the reoperation rate, survivorship and clinical outcome scores.

Methods

The US National Library of Medicine (PubMed/MEDLINE), EMBASE, and the Cochrane Database of Systematic Reviews were queried for publications from January 1980 to December 2019 utilizing the following keywords: "medial pivot", "medial stabilized", "medial rotating", "medial congruent", medial ball and socket", "arthroplasty", "TKA", "TKR", and "knee surgery".

Results

18 articles met the inclusion criteria for the present study. The average quality was 11.4 for non-comparative studies and 21.7 for comparative studies based on MINORS criteria. A total 2832 knee arthroplasties were included for the final analysis with an average age of 69 years, and an average follow-up of 8.1 years (minimum 5 years). The overall reoperation rate was 2.4%, with periprosthetic joint infection as the leading cause of revision in 0.9% of cases, followed by aseptic loosening in 0.4% of cases. The average Knee Society Score improved to a mean preoperative score of 40.1 to a mean postoperative score of 89.2. The functional knee society score improved from a mean preoperative score of 44.8 to an average postoperative score of 82.9. The global range of motion improved from 104.8° preoperatively to 115.6° postoperatively.

Conclusion

We found that medial pivot system in primary total knee arthroplasty provide overall mid-term survivorship comparable to other standard implasnts. In addition, medial pivot system is associated with better high-end function compared to standard implants.

Correlation of quality of life with instrumented analysis of a total knee arthroplasty series at the long-term follow-up

PURPOSE

The relationship between instrumented knee measurements and patient-reported outcome measures is a newer field that continues to evolve. The aim of this study was to evaluate long-term quality of life (QoL) post-total knee arthroplasty (TKA) surgery correlating validated self-reported questionnaires, clinical examination and instrumented analysis, using baropodometry and accelerometry.

METHODS

Thirty-six patients who underwent primary unilateral TKA between 1999 and 2006 were evaluated at 11.3 ± 2.3 years following surgery. Clinical examination included range of motion (ROM) and instrumented knee laxity measurements with the Rolimeter device. The visual analogue scale (VAS) for pain was also recorded. The utilised subjective outcome scores were the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the short form of World Health Organisation Quality of Life (WHOQOL-BREF). Instrumented analysis was performed with baropodometry and accelerometry. QoL was assessed correlating clinical, subjective and instrumented results. Univariate analysis included the Spearman's Rho correlation coefficient and Mann-Whitney tests.

RESULTS

At the long-term follow-up all patients had relatively high quality of life measurements, as well as functional scores, except for the Sport/Rec dimension of the KOOS score. Only cadence (p = 0.008) and velocity (p = 0.026) affected the WHOQOL psychology domain no matter the age, follow-up and gender of the patients. The domain was unaffected by VAS and Rolimeter measurements. WHOQOL Social domain was unaffected by all instrumentation measurements except for stance phase (p = 0.025), VAS (p = 0.005) and ROM (p = 0.028). KOOS physical domain was not affected by any parameter. KOOS pain was reversely affected by VAS (p = 0.004), KOOS symptom by ROM (p = 0.000 and median maximum pressure (p = 0.033).

CONCLUSION

Quality of life for the TKA patient can be correlated and assessed reliably with instrumented analysis using pedobarography and accelerometry, at the long-term follow-up.

LEVEL OF EVIDENCE

III.

End-stage knee osteoarthritis with and without sarcopenia and the effect of knee arthroplasty - a prospective cohort study

Background

Sarcopenia often accompanies osteoarthritis (OA), which is managed by total knee arthroplasty (TKA) in the late stage. Recent studies have suggested a higher risk of post-operative complications after TKA in sarcopenic OA subjects, but whether TKA can benefit them similar to non-sarcopenic subjects remains unexplored. This study aimed to examine the dynamic, mutual impact of sarcopenia and TKA in a one-year post-operative period.

Methods

This prospective cohort study was conducted between 2015 to 2018 at our hospital. Patients with end-stage OA of the knee waiting for TKA were recruited into the study. Primary outcome measures were change in muscle strength, mass and function. Secondary outcome measures were quality of life (QOL) measurements for pain, psychological and physical health.

Results

Fifty-eight patients were recruited, of which 79.3% were female and 32.8% already had sarcopenia at baseline. The average age of sarcopenic subjects and non-sarcopenic subjects was comparable (67.89 ± 7.07 vs. 67.92 ± 6.85; p = 0.99), but sarcopenic subjects had a lower body mass index (BMI) (25.64 ± 2.64 vs. 28.57 ± 4.04; p = 0.01). There was a statistically significant improvement in walking speed (10.24 ± 5.35 vs. 7.69 ± 2.68, p < 0.01) and muscle strength in both sarcopenic and non-sarcopenic patients after TKA. This was accompanied by an improvement trend in muscle mass in all subjects. There was no change in handgrip power before and after TKA and subsequent follow-up (19.31 ± 5.92 vs. 18.98 ± 6.37 vs. 19.36 ± 7.66; p = 0.97). QOL measured before, after and at follow-up with WOMAC (total: 42.27 ± 15.98 vs. 20.65 ± 15.24 vs. 16.65 ± 18.13) and SF12v2 (PCS: 33.06 ± 8.55 vs. 38.96 ± 8.01 vs. 40.67 ± 7.93) revealed progressive significant improvement (both comparisons p ≤ 0.01). Further analysis with the IPAQ also found increased engagement of high-intensity activities.

Conclusions

This study showed that sarcopenia among patients with end-stage OA of the knee is not uncommon, but both sarcopenic and non-sarcopenic OA patients achieved significant clinical and functional improvement after TKA. Further studies with a larger sample size and different ethnicities could help ascertain a beneficial role of TKA in sarcopenic OA subjects.

Trial registration

Registry: ClinicalTrials.gov, Registration number: NCT03579329. Date of registration: 6 July 2018. Retrospectively registered.

Risk factors of pain, physical function, and health-related quality of life in elderly people with knee osteoarthritis: A cross-sectional study

Data on the precise mechanisms of the complex interactions of factors related to clinical impact of knee osteoarthritis (KOA) in the elderly population remain limited. To find predictors that explain pain intensity, physical function, and quality of life in elderly KOA subjects, we performed a cross-sectional analysis of the baseline data from a randomized trial. The trial included 104 subjects (aged ≥60) with KOA pain and dysfunctional endogenous pain-inhibitory system activity assessed by conditioned pain modulation (CPM). Three multiple linear regression models were performed to understand the independent predictors of Brief Pain Inventory (BPI), WOMAC function subscale (WOMACFunc), and SF-12 physical subscale (SF12-PCS). Model 1 showed that BPI pain score was predicted by low CPM response, high von-Frey light touch threshold, worse radiological severity as indexed by Kellgren-Lawrence grade (KL), high von-Frey punctate pain intensity and high levels of anxiety (adjusted R2 = 27.1%, F (6,95) = 7.27, P < 0.0001). In model 2, von-Frey light touch threshold, KL, depressive symptoms indexed by Beck Depression Inventory (BDI), level of sleepiness and pain pressure threshold were risk factors for SF12-PCS (adjusted R2 = 31.9%, F (5,96) = 10.5, P < 0.0001). Finally, model 3 showed that WOMACFunc was predicted by BDI, KL and BPI (adjusted R2 = 41%, F (3,98) = 24.42, P < 0.0001). Our data provides an interesting framework to understand the predictors of KOA pain in the elderly and highlights how its related outcomes are affected by disease-specific factors, somatosensory dysfunction and emotional factors.

[A Structural Equation Model of Health-Related Quality of Life among Older Women Following Bilateral Total Knee Replacement]

PURPOSE

This study aimed to develop and test a structural equation model of health-related quality of life among older women following bilateral total knee replacement based on a literature review and Wilson and Cleary's model of health-related quality of life.

METHODS

One hundred ninety three women who were diagnosed with osteoarthritis, were older than 65 years, and were between 13 weeks and 12 months of having a bilateral total knee replacement were recruited from an outpatient clinic. Data were collected from July 2017 to April 2018 using a structured questionnaire and medical records. Data were analyzed using SPSS/WIN 22.0, AMOS 22.0, and Smart PLS 3.2.4.

RESULTS

The fitness of the hypothetical model was good, with coefficients of determination (R²) ranging between .28 and .75 and predictive relevance (Q²) between .26 and .73. The standardized root mean square residual of the model fit indices for the hypothetical model was .04; which explained 64.2% of physical and 62.5% of mental health-related quality of life. Self-efficacy, symptom status, functional status, and general health perceptions had a significant direct effect on physical health-related quality of life, while social support, symptom status, and general health perceptions had a significant direct effect on participants' mental-health-related quality of life.

CONCLUSION

To improve the physical and mental quality of life of older women who receive bilateral knee replacement, nursing-based intervention strategies that reduce symptoms, improve functional status, and increase health perceptions, self-efficacy, and social support are needed. The most important factor is the symptom status.

RELATIONSHIP BETWEEN THE KNEE AND HINDFOOT AXES IN PATIENTS WITH SEVERE KNEE OSTEOARTHRITIS

OBJECTIVE

To evaluate the correlation between knee axis and hindfoot axis in patients with advanced gonarthrosis, and the association between ankle function and angular deformities.

METHODS

72 patients were enrolled in the study: 66% were women, and mean age was 58.7 years. The anatomical axis of the knee and hindfoot were measured by short knee radiographs and long axial view of the hindfoot.

RESULTS

Among the study group, 79.2% presented varus knee (mean 15º ± 7.69º) and 20.8% valgus (mean 15.9º ± 7.7º). 63.9% had hindfoot varus (mean 8.5º ± 6.07º) and 36.1% valgus (mean 3.9º ± 3.92º) (p < 0.05). The mean value for the American Orthopaedic Foot and Ankle Society (AOFAS) score was 74.26 points, and values were significantly higher among patients with hindfoot varus (p < 0.05). We found no correlation between gender or AOFAS score and knee and hindfoot axes, nor between deformities in the knee and hindfoot axes (p > 0.05). The subgroup genu valgum - hindfoot varus presented a moderate correlation (r = 0.564; p < 0.05).

CONCLUSION

We found no association between the anatomical axes of the knee and hindfoot. Patients with gonarthrosis and hindfoot varus presented a better ankle function. Level of Evidence II, Prognostic Studies - Investigating the Effect of a Patient Characteristic on the Outcome of Disease.

Should Oral Corticosteroids be Used in Medical Therapy for Chronic Rhinosinusitis? A Risk Analysis

OBJECTIVES

Oral corticosteroid (OCS) as a part of appropriate medical therapy (AMT) (formerly maximal medical therapy) in chronic rhinosinusitis remains controversial. While the risks of OCS are well known, the benefit remains unclear due the absence of a standardized prescribing regimen. Consequently, it is difficult to characterize whether the risks of OCS and its ability to avert endoscopic sinus surgery (ESS) are helpful in AMT. When OCS is highly effective at averting surgery, the lesser risks of OCS would be justified because it can avoid the greater risks of ESS. When OCS is poorly effective at averting ESS, the risks of OCS would not be justified because many patients will be exposed to both risks. This study seeks to identify the threshold effectiveness of OCS at averting ESS that would minimize risk exposure to patients.

METHODS

A probabilistic risks-based decision analysis was constructed from literature reported incidences and impacts of adverse events of OCS and ESS. Monte Carlo analysis was performed to identify the minimum effectiveness required to avoid further intervention (MERAFI) for chronic sinusitis without nasal polyp (CRSsNP) and chronic sinusitis with nasal polyp (CRSwNP).

RESULTS

The analysis showed MERAFI results of 20.8% (95% CI 20.7-20.9%) for CRSsNP and 16.8% (95% CI 16.7-16.9%) for CRSwNP.

CONCLUSIONS

Given reported OCS effectiveness in the range of 34-71% in CRSsNP and 46-63% in CRSwNP, this analysis suggests that the inclusion of OCS in AMT may be the lower risk strategy.

LEVEL OF EVIDENCE

N/A Laryngoscope, 131:473-481, 2021.

Opposing needling for analgesia and rehabilitation after unilateral total knee arthroplasty: a randomized, sham-controlled trial protocol

Background

This randomized controlled clinical trial aims to evaluate the efficacy and safety of opposing needling in patients undergoing unilateral total knee arthroplasty (TKA). Opposing needling is one of the special needling methods used in acupuncture and moxibustion therapy. It involves needling acupoints on the contralateral side for pain management. Although, opposing needling is used for pain management in clinics, evidence to support its effectiveness as an analgesic after total knee arthroplasty is scant. We designed a randomized controlled clinical trial to evaluate efficacy and safety of opposing electroacupuncture (EA) in alleviating pain associated with unilateral total knee arthroplasty.

Methods/design

This is a protocol for a randomized controlled patient- and assessor-blinded trial with three parallel arms (A, opposing EA; B, operated side EA; C, sham EA). Yinlingquan (SP9), Yanglingquan (GB34), Futu (ST32), and Zusanli (ST36) acupoints are selected for all three groups. In group A, the healthy side will be treated with EA, while the operated side will be administered sham EA. In group B, the operated side will be treated with EA while on the healthy side sham EA will be used. For group C, sham EA will be used on both sides. All patients in the three groups will receive treatment once a day for 3 days. The post-operative pain measured using a visual analogue scale score (including pain while resting and being active) and the additional dose of the patient-controlled analgesic pump after operation will be recorded as the primary outcomes. Secondary outcomes such as knee function and swelling, range of motion (including active and passive range of motion), post-operative anxiety, and acupuncture tolerance will also be assessed.

Discussion

Opposing needling is a potential non-pharmacological treatment for relieving pain and improving functional rehabilitation after TKA, during which patients receive acupuncture on the healthy side rather than on the operated side. This sham controlled clinical trial, designed to evaluate efficacy and safety of opposing needling for patients after TKA, will provide evidence for pain management and functional rehabilitation after unilateral TKA.

Trial registration

ChiCTR, ChiCTR1800020297 (http://www.chictr.org.cn/edit.aspx?pid=34231&htm=4). Registered 22 December 2018.

Patient characteristics and valuation changes impact quality of life and satisfaction in total knee arthroplasty - results from a German prospective cohort study

Background

Evaluation of variations in pre- and postoperative patient reported outcomes (PRO) and the association between preoperative patient characteristics and health and satisfaction outcomes after total knee arthroplasty (TKA) may support shared decision-making in Germany. Since previous research on TKA health outcomes indicated valuation differences in longitudinal data, experienced-based population weights were used for the first time as an external valuation system to measure discrepancies between patient and average population valuation of HRQoL.

Methods

Baseline data (n = 203) included sociodemographic and clinical characteristics and PROs, measured by the EQ-5D-3 L and WOMAC. Six-month follow-up data (n = 161) included medical changes since hospital discharge, PROs and satisfaction. A multivariate linear regression analysis was performed to evaluate the relationship between preoperative patient characteristics and PRO scores. Patient acceptable symptom state (PASS) was calculated to provide a satisfaction threshold. Patient-reported health-related quality of life (HRQoL) valuations were compared with average experienced-based population values to detect changes in valuation.

Results

One hundred thirty-seven subjects met inclusion criteria. All PRO measures improved significantly. Preoperative WOMAC and EQ-5D VAS, housing situation, marital status, age and asthma were found to be predictors of postoperative outcomes. 73% of study participants valued their preoperative HRQoL higher than the general population valuation, indicating response shift. Preoperatively, patient-reported EQ-5D VAS was substantially higher than average experienced-based population values. Postoperatively, this difference declined sharply.

Approximately 61% of the patients reported satisfactory postoperative health, being mainly satisfied with results if postoperative WOMAC was ≥82.49 (change ≥20.25) and postoperative EQ-5D VAS was ≥75 (change ≥6).

Conclusion

On average, patients benefited from TKA. Preoperative WOMAC and EQ-5D VAS were predictors of postoperative outcomes after TKA. Particularly patients with high absolute preoperative PRO scores were more likely to remain unsatisfied. Therefore, outcome prediction can contribute to shared-decision making. Using general population valuations as a reference, this study underlined a discrepancy between population and patient valuation of HRQoL before, but not after surgery, thus indicating a potential temporary response shift before surgery.

Validation of a Novel Device for the Knee Monitoring of Orthopaedic Patients

Fast-track surgery is becoming increasingly popular, whereas the monitoring of postoperative rehabilitation remains a matter of considerable debate. The aim of this study was to validate a newly developed wearable system intended to monitor knee function and mobility. A sensor system with a nine-degree-of-freedom (DOF) inertial measurement unit (IMU) was developed. Thirteen healthy volunteers performed five 10-meter walking trials with simultaneous sensor and motion capture data collection. The obtained kinematic waveforms were analysed using root mean square error (RMSE) and correlation coefficient (CC) calculations. The Bland–Altman method was used for the agreement of discrete parameters consisting of peak knee angles between systems. To test the reliability, 10 other subjects with sensors walked a track of 10 metres on two consecutive days. The Pearson CC was excellent for the walking data set between both systems (r = 0.96) and very good (r = 0.95) within the sensor system. The RMSE during walking was 5.17° between systems and 6.82° within sensor measurements. No significant differences were detected between the mean values observed, except for the extension angle during the stance phase (E1). Similar results were obtained for the repeatability test. Intra-class correlation coefficients (ICCs) between systems were excellent for the flexion angle during the swing phase (F1); good for the flexion angle during the stance phase (F2) and the re-extension angle, which was calculated by subtracting the extension angle at swing phase (E2) from F2; and moderate for the extension angle during the stance phase (E1), E2 and the range of motion (ROM). ICCs within the sensor measurements were good for the ROM, F2 and re-extension, and moderate for F1, E1 and E2. The study shows that the novel sensor system can record sagittal knee kinematics during walking in healthy subjects comparable to those of a motion capture system.

Assessment of functional recovery after total hip and knee arthroplasty: An observational study of 95 patients

BACKGROUND

A significant proportion of patients experience functional limitations following total hip and knee arthroplasty (THA and TKA). The purpose of this study was to investigate prospectively the patient-reported and objectively assessed functional recovery following THA and TKA.

METHODS

Patients were recruited at a regional Danish hospital, using a prospective, observational hypothesis-generating cohort design. Primary outcome measures were performance-based function (30-s chair-stand test) and self-reported physical function measured by the Hip Disability and Osteoarthritis Outcome Score (HOOS) for those who had undergone THA, and the Knee Injury and Osteoarthritis Outcome Score (KOOS) for those who had undergone TKA. In addition, patient expectations, the "forgotten joint" scale and pain catastrophizing were measured. Outcome measures were collected at baseline (preoperatively) and at follow-up (4 months postoperatively).

RESULTS

A total of 95 patients (59 who had undergone THA and 36 who had undergone TKA) were recruited. Performance-based function improved only slightly, with a mean difference of 2.9 (95% confidence interval [CI] 1.9, 4.0) for THAs and 1.6 (95% CI 0.4, 2.8) for TKAs. Self-reported physical function improved significantly, with a mean difference of 37.9 (95% CI 31.5, 44.3) for THAs and 28.6 (95% CI 22.7, 34.4) for TKAs. However, dividing the cohort into "improved" and "non-improved" groups based on changes in performance-based function, no clinically relevant predictors for poor performance-based outcome could be found.

CONCLUSIONS

Self-reported outcome measures improved significantly following THA and TKA, whereas performance-based function improved only slightly by the 4-month follow-up. The subgroup that did not improve in performance-based function still reported significant improvements in self-reported outcome measures, demonstrating the difficulty in predicting optimal rehabilitation strategies after THA and TKA.

Effects of low-intensity pulsed ultrasound on recovery of physical impairments, functional performance and quality of life after total knee arthroplasty: Protocol for a quasi-experimental study

INTRODUCTION

The presence of significant pain and swelling during the acute stage following total knee arthroplasty (TKA) may limit the patients' ability to cooperate in intensive physiotherapy interventions. Low-intensity pulsed ultrasound is one of the modalities that can be used for acute pain and swelling management. However, only one study investigated the effect of this modality in patients with TKA. There is limited documentation of the effects of combining low-intensity pulsed ultrasound in TKA rehabilitation in the recovery of physical impairments and how these influence the recovery of function after TKA. Therefore, this study is proposed with the aim to evaluate the effects of low-intensity pulsed ultrasound as an adjunct to conventional physiotherapy on the recovery of physical impairments, functional performance and quality of life after TKA surgery.

METHODS

This is an assessor-blinded quasi-experimental study comparing two approaches of physiotherapy, namely pulsed ultrasound-added physiotherapy and conventional physiotherapy. Total number of participants with TKA required for this study will be calculated based on the result of a pilot study. Participants will be alternately allocated into either pulsed ultrasound-added physiotherapy group (low-intensity pulsed ultrasound and conventional physiotherapy) or control group (conventional physiotherapy). Pulsed ultrasound-added physiotherapy group will receive low-intensity pulsed ultrasound starting at post-operative day 2 (4-5 times for the first-week after surgery and 2-3 times a week for a further 2 weeks). Both groups will receive conventional physiotherapy 4 to 5 times for the first-week after surgery and 2 to 3 times a week for a further 11 weeks. This procedure and process will be tested and established in a pilot study. Primary outcomes of interest are pain level, swelling, active range of knee motion, and quadriceps strength. The secondary outcomes are functional performance and quality of life.

DISCUSSION

This study will fill the gaps in knowledge relating the benefits of including low-intensity pulsed ultrasound into conventional physiotherapy for patients with TKA.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry, ACTRN12618001226291.

Differential item functioning of the SF-12 in a population-based regional joint replacement registry

Background

Joint replacement, an increasingly common procedure amongst older adults, can substantially improve health-related quality of life (HRQoL). However, differential item functioning (DIF) may affect the accurate interpretation of differences in HRQoL amongst patients with different demographic and health status characteristics but the same underlying (i.e., latent) level of the investigated construct. This study tested for DIF in pre-operative SF-12 physical health (PH) and mental health (MH) sub-scale items amongst patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA).

Methods

Data were from a population-based joint replacement registry from the Canadian province of Manitoba. TKA and THA patients who had surgery between 2009 and 2015 and completed a pre-operative assessment were included. DIF was tested using the multiple indicators multiple causes (MIMIC) method with sex, age group, body weight status, and presence of multiple comorbid conditions (i.e., multimorbidity) as covariates. Analyses were stratified by joint type.

Results

The study cohort included 8820 patients; 42.1% underwent THA, 57.3% were female, 32.7% were 70+ years, and 52.8% were obese. For each sub-scale, four of the six items exhibited DIF in both THA and TKA groups. Differences in the covariate effect estimates for DIF and No-DIF models on the MH latent variable were largest for age and body weight status for the THA group, and for sex and multimorbidity for the TKA group. All of the differences were small for PH. Multimorbidity had the strongest association with PH and age and sex had the strongest association with MH in the DIF models.

Conclusions

Demographic and health status characteristics influenced SF-12 PH and MH item responses in joint replacement populations, although the size of the effects were not large for PH. We recommend testing and adjusting for DIF effects to ensure comparability of HRQoL measures in joint replacement populations.

Electronic supplementary material

The online version of this article (10.1186/s12955-019-1166-1) contains supplementary material, which is available to authorized users.

Evaluation of Surgical Wound Healing in Orthopedic Patients with Impaired Tissue Integrity According to Nursing Outcomes Classification

PURPOSE

To assess the surgical wound (SW) healing in orthopedic patients with Impaired tissue integrity according to the Nursing Outcomes Classification (NOC).

METHODS

A prospective longitudinal study performed with 24 patients. Data collection was performed through an instrument containing the NOC indicators.

FINDINGS

The indicators skin approximation, drainage, surrounding skin erythema, periwound edema, increased skin temperature, and foul wound odor presented a statistically significant increase when compared the means between the first and the last day of evaluation.

CONCLUSION

The NOC indicators allowed to monitor the SW healing indicating an improvement.

IMPLICATIONS FOR NURSING PRACTICE

The NOC can favor an earlier identification of the degree of commitment for each patient and enables implementation of care to achieve target outcomes.

Balance and quality of life after total knee arthroplasty

OBJECTIVE

To evaluate the change in balance and quality of life in patients undergoing total knee arthroplasty for primary gonarthrosis.

METHOD

Patients aged 60 years or older were evaluated in relation to the balance and quality of life before total knee arthroplasty and six months after surgery. To assess balance, this study used the Motor Scale Test for the Elderly; quality of life was assessed using the Western Ontario and McMaster Universities Osteoarthritis Index questionnaire and the Short Form Health Survey. A control group consisting of healthy adults, age- and gender-paired, was used to compare the balance after surgery results.

RESULTS

Twenty-eight patients completed the study, of a total of 37 arthroplasties. The mean age was 70.18 ± 6.17 years. All variables were statistically significant (p ≤ 0.05) for improved balance and quality of life after arthroplasty. It was observed that, after knee arthroplasty, the level of balance does not reach that expected for healthy individuals (p ≤ 0.05).

CONCLUSION

Total knee arthroplasty is effective at improving balance six months after surgery, as well as all domains of quality of life. However, it is not able to restore balance to a level comparable to that of healthy individuals.

Quality of life after staged bilateral total knee arthroplasty: a minimum five-year follow-up study of seventy-eight patients

PURPOSE

Although many studies have been performed to evaluate the quality of life (QOL) and patient satisfaction after total knee arthroplasty (TKA), almost all evaluations were performed in patients after unilateral TKA or in patients after mixed unilateral and bilateral TKA. Accordingly, this study aimed to evaluate QOL after staged bilateral TKA.

METHODS

A total of 78 patients who underwent staged bilateral TKA for varus knee osteoarthritis were included in this study. All patients had longitudinal follow-up evaluations for at least five years. QOL was assessed by the Japanese Knee Osteoarthritis Measure (JKOM), a disease-specific and patient-derived QOL measure for Japanese patients. Conventional objective outcome scales, including the Knee Society Score and the Timed Up and Go test, were also assessed. In addition, QOL and objective outcomes were compared between the younger (≤ 80 years, average 75.8 years) and older (> 80 years, average 84.7 years) age groups at the final follow-up.

RESULTS

Improvements in both JKOM and objective outcomes reached a plateau one year after staged bilateral TKA. Improvements were prolonged for more than five years. There were no statistically significant differences in JKOM or objective outcomes between the younger and older age groups, despite an 8.9-year difference in the average age.

CONCLUSIONS

This was the first longitudinal study to evaluate QOL and objective outcomes after staged bilateral TKA for a period of at least five years. Improvements in QOL and objective outcomes reached a plateau one year after staged bilateral TKA and were prolonged for more than five years. No significant differences were observed in outcome scores between the younger and older age groups.

Impact of a tailored activity counselling intervention during inpatient rehabilitation after knee and hip arthroplasty - an explorative RCT

Background

The aim of the study was to improve physical activity (PA), well-being and clinical outcome after total knee and hip arthroplasty through tailored activity counselling during inpatient rehabilitation.

Methods

65 patients (aged 70.4 ± 7.3 years, BMI 28.5 ± 4.3) starting inpatient rehabilitation after primary knee or hip arthroplasty due to osteoarthritis were recruited and pseudo-randomized into an intervention (IG) and a control group (CG). Twice a week, the IG was encouraged to increase their daily step count by 5%. PA, e. g. number of steps, step frequency, or active minutes, was measured by step activity monitoring. Well-being and clinical outcome were assessed using the SF-36, Oxford Knee/Hip Score and Global rating of Change. Procedures were conducted at the onset of inpatient rehabilitation, and repeated one and 6 months after inpatient rehabilitation.

Results

Data sets were obtained from 49 patients (IG: n = 23, CG: n = 26). Both groups significantly increased their number of daily steps from the 1 month to the 6 months follow up after rehabilitation: CG: 9019 (95%CI: 7812, 10,226), IG: 9280 (7972, 10,588) and CG: 10921 (9571, 12,271), IG: 11326 (9862, 12,791) respectively. Additionally, well-being and clinical outcome improved significantly in both groups. No significant differences in physical activity, clinical outcome and well-being were found between the groups.

Conclusions

PA counselling during inpatient rehabilitation does not improve PA, well-being and clinical outcome in patients with primary knee or hip arthroplasty in addition to the rehabilitation program. PA interventions may be more effective after the completion of the inpatient rehabilitation phase.

Trial registration

DRKS DRKS00012682. Registered retrospectively on 03–07- 2017.

The prognostic value of pain catastrophizing in health-related quality of life judgments after Total knee arthroplasty

Background

Total knee arthroplasty (TKA) is a highly effective procedure that yields reductions in pain and disability associated with end stage osteoarthritis (OA) of the knee. Quality of life instruments are frequently used to gauge the outcomes of total knee arthroplasty (TKA). However, research suggests that post-TKA reductions in symptom severity may not be the sole predictors of quality of life post-TKA. The primary objective of the present study was to examine the prognostic value of catastrophic thinking in health-related quality of life (HRQoL) judgments in patients with severe OA after TKA.

Methods

In this study we used a prospective cohort design to examine the value of pain catastrophizing in predicting HRQoL 1 year after TKA. Participants with advanced OA of the knee who were scheduled for TKA were recruited at one of three hospitals in Canada. The study sample consisted of 116 individuals (71 women, 45 men) who completed study questionnaires at their pre-surgical evaluation and 1 year after surgery. Hierarchical regression analysis was used to assess the unique contribution of pre-surgical pain catastrophizing to the prediction of post-surgical HRQoL judgments.

Results

The results of the hierarchical regression equation revealed that the overall model was significant, F (9,106) = 8.3, p < 001, and accounted for 36.4% of the variance in the prediction of post-surgical physical component score of HRQoL. Pain catastrophizing was entered in the last step of the equation and contributed significant unique variance (β = −.35, p < .001) to the prediction of post-surgical physical component score of HRQoL above and beyond the variance accounted for by demographic variables, co-morbid health conditions, baseline HRQoL, and post-surgical reductions in pain, joint stiffness and physical disability.

Conclusions

The current findings highlight the importance of pre-surgical catastrophic cognitions in influencing HRQoL judgments after TKA. The findings suggest that psychosocial interventions designed to reduce pain catastrophizing before TKA might contribute to better quality of life outcomes following surgery.

Development of a clinical risk score for pain and function following total knee arthroplasty: results from the TRIO study

Objectives

The aim was to develop and validate a simple clinical prediction model, based on easily collected preoperative information, to identify patients at high risk of pain and functional disability 6 months after total knee arthroplasty (TKA).

Methods

This was a multicentre cohort study of patients from nine centres across the UK, who were undergoing a primary TKA for OA. Information on sociodemographic, psychosocial, clinical and quality-of-life measures were collected at recruitment. The primary outcome measure for this analysis was the Oxford knee score (OKS), measured 6 months postoperatively by postal questionnaire. Multivariable logistic regression was used to develop the model. Model performance (discrimination and calibration) and internal validity were assessed, and a simple clinical risk score was developed.

Results

Seven hundred and twenty-one participants (mean age 68.3 years; 53% female) provided data for the present analysis, and 14% had a poor outcome at 6 months. Key predictors were poor clinical status, widespread body pain, high expectation of postoperative pain and lack of active coping. The developed model based on these variables demonstrated good discrimination. At the optimal cut-off, the final model had a sensitivity of 83%, specificity of 61% and positive likelihood ratio of 2.11. Excellent agreement was found between observed and predicted outcomes, and there was no evidence of overfitting in the model.

Conclusion

We have developed and validated a clinical prediction model that can be used to identify patients at high risk of a poor outcome after TKA. This clinical risk score may be an aid to shared decision-making between patient and clinician.

Sports activity is maintained or increased following total knee arthroplasty

PURPOSE

The purpose of this study was to investigate sports activities and functional abilities in patients following total knee arthroplasty (TKA). It was hypothesized that patients who had undergone TKA would return to a higher activity level as that experienced preoperatively.

METHODS

Two hundred patients were included in this prospective single-cohort study. All the patients completed subjective questionnaires (Tegner Activity Level, Oxford Knee Score, Visual Analog Scale for pain) prior to surgery as well as at 6, 12, and 24 months postoperatively. Additionally, sports behaviour was evaluated. Sports frequency was divided into four categories: more than 5 times a week, 2-3 times a week, occasionally, and no sports activities. Additionally, the patients were asked to state their three favourite summer and winter sports.

RESULTS

All patient-reported outcome scores improved significantly over time (p ≤ 0.005). The Tegner Activity Level increased significantly from the preoperative state to 24 months postsurgery (p = 0.005). Six months after surgery, 43% of the patients returned to the same and 35% to a higher Tegner Activity Level than prior to surgery. Gender-related differences were observed for the Tegner Activity Level showing a higher activity level for the male than for the female patients. Overall, 24 months postsurgery 83% of the patients practiced sports in comparison with 79% prior to surgery.

CONCLUSIONS

Following TKA, the patients were able to increase sports performance, while pain was reduced. Therefore, patients who want to continue their desired sports may safely consider TKA.

LEVEL OF EVIDENCE

II.

Effects of sex and obesity on gait biomechanics before and six months after total knee arthroplasty: A longitudinal cohort study

BACKGROUND

Gait biomechanics, sex, and obesity can contribute to suboptimal outcomes from primary total knee arthroplasty. The aims of this study were to i) determine if sex and/or obesity influence the amount of change in gait biomechanics from pre-surgery to six months post-surgery and; ii) assess if gait returns to normal in men and women.

METHODS

Three-dimensional gait analysis was performed on 43 patients undergoing primary total knee arthroplasty for knee osteoarthritis (pre- and six months post-operative) and 40 asymptomatic controls. Mixed linear regression models were fit to assess which factors influenced change in gait biomechanics within the arthroplasty cohort, and interaction terms were included to assess if biomechanics returned to normal following surgery.

FINDINGS

Male peak knee adduction moment (p < 0.001) and impulse (p < 0.001) decreased six months following arthroplasty, whilst gait in women remained unchanged after surgery. Obesity did not influence gait changes in men or women. Gait of female arthroplasty participants did not differ from female controls after surgery except for sagittal plane knee range of motion (p = 0.003), whilst men differed from controls for peak knee adduction moment (p = 0.011), knee range of motion (p < 0.001), and peak knee flexion moment (p < 0.001).

INTERPRETATION

Sex, but not obesity, influenced changes in gait biomechanics after arthroplasty. Men retained abnormal gait patterns after surgery, whilst women did not. Further research should determine the long-term implications of gait abnormalities seen in men after arthroplasty.

Total knee arthroplasty status and patient-reported, knee-related quality of life over a 4-year follow-up period: data from the osteoarthritis initiative

PURPOSE

To examine the relationship between baseline total knee arthroplasty (TKA) status and patient-reported, knee-related quality of life (QoL) over a 4-year follow-up relative to no knee osteoarthritis (OA).

PATIENTS AND METHODS

Data from the Osteoarthritis Initiative were included, comprising 4,674 adults aged 45-79 years at baseline. Patients were categorized into four groups: no knee OA (n=3,711), non-TKA (n=902), pre-TKA (n=36), and post-TKA (n=25). QoL was measured using the Knee Injury Osteoarthritis Outcome Score-QoL subscale. General linear mixed models were used for the relationship between TKA and QoL.

RESULTS

After adjusting for covariates, a reduced QoL was noted for patients in the non-TKA (mean [standard error], -13.97 [0.73]; P<0.0001), pre-TKA (-21.34 [3.57]; P<0.0001), and post-TKA (-9.68 [3.94]; P=0.0143) groups compared with the no knee OA group. QoL in the non-TKA group also decreased over time (-0.16 [0.07]; P=0.226).

CONCLUSION

Non-, pre-, and post-TKA status is associated with a lower QoL.

Impact of total knee replacement practice: cost effectiveness analysis of data from the Osteoarthritis Initiative

Objectives To evaluate the impact of total knee replacement on quality of life in people with knee osteoarthritis and to estimate associated differences in lifetime costs and quality adjusted life years (QALYs) according to use by level of symptoms.Design Marginal structural modeling and cost effectiveness analysis based on lifetime predictions for total knee replacement and death from population based cohort data.Setting Data from two studies-Osteoarthritis Initiative (OAI) and the Multicenter Osteoarthritis Study (MOST)-within the US health system.Participants 4498 participants with or at high risk for knee osteoarthritis aged 45-79 from the OAI with no previous knee replacement (confirmed by baseline radiography) followed up for nine years. Validation cohort comprised 2907 patients from MOST with two year follow-up.Intervention Scenarios ranging from current practice, defined as total knee replacement practice as performed in the OAI (with procedural rates estimated by a prediction model), to practice limited to patients with severe symptoms to no surgery.Main outcome measures Generic (SF-12) and osteoarthritis specific quality of life measured over 96 months, model based QALYs, costs, and incremental cost effectiveness ratios over a lifetime horizon.Results In the OAI, total knee replacement showed improvements in quality of life with small absolute changes when averaged across levels of confounding variables: 1.70 (95% uncertainty interval 0.26 to 3.57) for SF-12 physical component summary (PCS); -10.69 (-13.39 to -8.01) for Western Ontario and McMaster Universities arthritis index (WOMAC); and 9.16 (6.35 to 12.49) for knee injury and osteoarthritis outcome score (KOOS) quality of life subscale. These improvements became larger with decreasing functional status at baseline. Provision of total knee replacement to patients with SF-12 PCS scores <35 was the optimal scenario given a cost effectiveness threshold of $200 000/QALY, with cost savings of $6974 ($5789 to $8269) and a minimal loss of 0.008 (-0.056 to 0.043) QALYs compared with current practice. These findings were reproduced among patients with knee osteoarthritis from the MOST cohort and were robust against various scenarios including increased rates of total knee replacement and mortality and inclusion of non-healthcare costs but were sensitive to increased deterioration in quality of life without surgery. In a threshold analysis, total knee replacement would become cost effective in patients with SF-12 PCS scores ≤40 if the associated hospital admission costs fell below $14 000 given a cost effectiveness threshold of $200 000/QALY.Conclusion Current practice of total knee replacement as performed in a recent US cohort of patients with knee osteoarthritis had minimal effects on quality of life and QALYs at the group level. If the procedure were restricted to more severely affected patients, its effectiveness would rise, with practice becoming economically more attractive than its current use.

The relationship between pain with walking and self-rated health 12 months following total knee arthroplasty: a longitudinal study

BACKGROUND

A subgroup of patients continue to report pain with walking 12 months after total knee arthroplasty (TKA). The association between walking pain and self-rated health (SRH) after TKA is not known. This prospective longitudinal study aimed to investigate the association between a comprehensive list of preoperative factors, postoperative pain with walking, and SRH 12 months after TKA.

METHODS

Patients (N = 156) scheduled for TKA completed questionnaires that evaluated demographic and clinical characteristics, symptoms, psychological factors, and SRH. SRH was re-assessed 12 months after TKA. Clinical variables were retrieved from medical records. Pain with walking was assessed before surgery, at 6 weeks, 3, and 12 months after TKA. Subgroups with distinct trajectories of pain with walking over time were identified using growth mixture modeling. Multiple linear regression was used to investigate the relationships between pain with walking and other factors on SRH.

RESULTS

Higher body mass index, a higher number of painful sites at 12 months, recurrent pain with walking group membership, ketamine use, higher depression scores, and poorer preoperative self-rated health were associated with poorer SRH 12 months after TKA. The final model was statistically significant (p = 0.005) and explained 56.1% of the variance in SRH 12 months after surgery. SRH improved significantly over time. Higher C-reactive protein levels, higher number of painful sites before surgery, higher fatigue severity, and more illness concern was associated with poorer preoperative SRH.

CONCLUSIONS

In patients whose walking ability decreases over time, clinicians need to assess for unreleaved pain and decreases in SRH. Additional research is needed on interventions to improve walking ability and SRH.

Greater pre-operative anxiety, pain and poorer function predict a worse outcome of a total knee arthroplasty

PURPOSE

Around 10-30 % of patients are dissatisfied with the results of their total knee arthroplasty (TKA). This review aimed to identify and evaluate the predictors of outcome measured by the three domains of health-related quality of life (pain, stiffness and function). The focus was on pre-operative psychological factors as related to other patient-related variables.

METHODS

A systematic search was performed using the following databases: MEDLINE, PubMed, AMED, CINAHL, PsychINFO, SciFinder, Scopus, EMBASE, Cochrane, Lilacs, Web of Science and ScienceDirect. The quality of identified studies was assessed using the Critical Appraisal Skills Programme Cohort checklist.

RESULTS

Ten studies met the eligibility criteria. From these, nine patient-related predictors of outcome were identified (depression, anxiety, age at surgery, gender (being female), medical co-morbidities, BMI, level of education, pre-operative pain severity and pre-operative knee function). Greater anxiety, pre-operative pain and function were the most significant factors to predict a poorer outcome of a TKA. The results of depression, gender (female), medical co-morbidities, BMI and level of education were variable among the included studies. There was very little evidence to support older age at operation as a predictor of poorer outcome.

CONCLUSION

Patients experiencing high levels of pain before surgery should be informed of the chances of improvement by having a TKA. A validated psychological screening tool that separates depression and anxiety is recommended as part of the pre-operative assessment stage. Patients presenting with symptoms of depression and anxiety should be identified and consulted before a TKA.

LEVEL OF EVIDENCE

II.

Psychiatric disease as a risk factor in fast-track hip and knee replacement

Recent studies suggest that patients with psychiatric disorders tend to do worse than patients without a psychiatric diagnosis when undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA). Whether this is due to their psychiatric condition, pharmacological treatment, a combination of the two, or something else has not been thoroughly analyzed-and there are no internationally accepted guidelines for perioperative management of psychiatric patients. This overview summarizes our current knowledge on perioperative risks in patients with preoperative psychiatric disorders and the possible role of psychotropic drugs in the perioperative course. This will be useful when planning future strategies for improvement of surgical outcome following hip and knee arthroplasty.

Comparison of Antagonist Muscle Activity During Walking Between Total Knee Replacement and Control Subjects Using Unnormalized Electromyography

BACKGROUND

Although satisfactory outcomes have been reported after total knee replacement (TKR), full recovery of muscle strength and physical function is rare. We developed a relative activation index (RAI) to compare leg muscle activity from unnormalized surface electromyography (sEMG) between TKR and control subjects.

METHODS

Nineteen TKR and 19 control subjects underwent gait analysis and sEMG. RAIs were calculated by dividing the average sEMG for 2 consecutive subphases of stance defined by the direction of the external sagittal plane moment (flexion or extension).

RESULTS

RAIs and external moments indicate TKR subjects have less initial stance antagonist rectus femoris activity (P = .004), greater middle stance antagonist biceps femoris activity (P < .001), and less late stance agonist biceps femoris activity (P < .001) than control subjects. Individuals with TKR demonstrate increased flexor muscle activation during weight bearing, potentially contributing to altered gait patterns found during the stance phase of gait.

CONCLUSION

The RAI helps detail whether decreased external moments correspond to less agonist or more antagonist muscle activity to determine true muscle activity differences between subject groups. Identifying the mechanisms underlying altered muscle function both before and after TKR is critical for developing rehabilitation strategies to address functional deficits and disability found in this patient population.