Trajectories of Pain and Function after Primary Hip and Knee Arthroplasty: The ADAPT Cohort Study

Patient-Reported Outcomes Following Periprosthetic Joint Infection of the Hip and Knee: A Longitudinal, Prospective Observational Study

BACKGROUND

The role of patient-reported outcome measures (PROMs) as tools for monitoring the impact and outcomes of periprosthetic joint infection (PJI) is not well described. This study analyzed the Oxford Hip Score (OHS) or Oxford Knee Score (OKS) in a prospective observational cohort of patients with hip or knee PJI.

METHODS

The PIANO (Prosthetic joint Infection in Australia and New Zealand, Observational study) cohort prospectively enrolled patients with newly diagnosed PJI from multiple centers. The OHS and OKS were evaluated at PJI diagnosis (baseline) and at 3, 12, and 24 months. Scores and score changes were examined according to PJI type, patient characteristics, and management. A successful functional outcome at 12 months was defined as an OHS of >38 or OHS of >36 and/or an improvement from baseline of >12 or >9, respectively.

RESULTS

Of the 741 participants, PROMs were available at 12 months for 233 with hip and 342 with knee PJI. Significant improvements (p < 0.0001) were seen at 12 months for both the OHS (24.5 to 36) and OKS (25 to 34), with no further improvement at 24 months. Patients with late-acute PJI had a higher median baseline OHS (35; interquartile range [22 to 46]) and OKS (30 [18 to 41]) than those with early PJI (OHS: 19 [15 to 29]; OKS: 22 [16 to 29.5]) or chronic PJI (OHS: 23 [14 to 34]; OKS 22 [14 to 28]). Logistic regression showed that a clinical cure (adjusted odds ratio [aOR] = 1.88, 95% confidence interval [CI] = 1.28 to 2.76, p = 0.001) and early PJI (aOR = 2.56, 95% CI = 1.64 to 4.07, p < 0.0001) independently predicted a successful functional outcome. Chronic renal impairment (aOR = 0.31, 95% CI = 0.13 to 0.71, p = 0.007), congestive cardiac failure (aOR = 0.41, 95% CI = 0.17 to 0.95, p = 0.04), and clinical signs of inflammation (aOR = 0.53, 95% CI = 0.33 to 0.85, p = 0.009) at diagnosis independently predicted failure to achieve a successful functional outcome.

CONCLUSIONS

The OHS and OKS varied significantly at baseline and 12 months according to PJI type, emphasizing the need to consider the PJI type when evaluating treatment success. This study highlights superior functional outcomes associated with early PJI and with achievement of a clinical cure.

LEVEL OF EVIDENCE

Therapeutic Level II . See Instructions for Authors for a complete description of levels of evidence.

Predicting Recovery Following Total Hip and Knee Arthroplasty Using a Clustering Algorithm

Background

Recovery following total joint arthroplasty is patient-specific, yet groups of patients tend to fall into certain similar patterns of recovery. The purpose of this study was to identify and characterize recovery patterns following total hip arthroplasty (THA) and total knee arthroplasty (TKA) using patient-reported outcomes that represent distinct health domains. We hypothesized that recovery patterns could be defined and predicted using preoperative data.

Methods

Adult patients were recruited from a large, urban academic center. To model postoperative responses to THA and TKA across domains such as physical health, mental health, and joint-specific measures, we employed a longitudinal clustering algorithm that incorporates each of these health domains. The clustering algorithm from multiple health domains allows the ability to define distinct recovery trajectories, which could then be predicted from preoperative and perioperative factors using a multinomial regression.

Results

Four hundred forty-one of 1134 patients undergoing THA and 346 of 921 undergoing TKA met eligibility criteria and were used to define distinct patterns of recovery. The clustering algorithm was optimized for 3 distinct patterns of recovery that were observed in THA and TKA patients. Patients recovering from THA were divided into 3 groups: standard responders (50.8%), late mental responders (13.2%), and substandard responders (36.1%). Multivariable, multinomial regression suggested that these 3 groups had defined characteristics. Late mental responders tended to be obese (P = .05) and use more opioids (P = .01). Substandard responders had a larger number of comorbidities (P = .02) and used more opioids (P = .001). Patients recovering from TKA were divided among standard responders (55.8%), poor mental responders (24%), and poor physical responders (20.2%). Poor mental responders were more likely to be female (P = .04) and American Society of Anesthesiologists class III/IV (P = .004). Poor physical responders were more likely to be female (P = .03), younger (P = .04), American Society of Anesthesiologists III/IV (P = .04), use more opioids (P = .02), and be discharged to a nursing facility (P = .001). The THA and TKA models demonstrated areas under the curve of 0.67 and 0.72.

Conclusions

This multidomain, longitudinal clustering analysis defines 3 distinct patterns in the recovery of THA and TKA patients, with most patients in both cohorts experiencing robust improvement, while others had equally well defined yet less optimal recovery trajectories that were either delayed in recovery or failed to achieve a desired outcome. Patients in the delayed recovery and poor outcome groups were slightly different between THA and TKA. These groups of patients with similar recovery patterns were defined by patient characteristics that include potentially modifiable comorbid factors. This research suggests that there are multiple defined recovery trajectories after THA and TKA, which provides a new perspective on THA and TKA recovery.

Level of Evidence

III.

The Impact of Acute Postoperative Pain in Developing Chronic Pain after Total Knee Arthroplasty

While total knee arthroplasties (TKAs) are performed with the intent to reduce pain, chronic postsurgical pain (CPSP) is one of the most well-documented complications that can occur following surgery. This study aimed to assess whether perioperative factors, focusing on acute postsurgical pain and perioperative opioid consumption, were associated with the development of chronic postsurgical pain. Under general anesthesia, 108 patients underwent TKA and were treated postoperatively with a multimodal analgesia approach. Numeric Rating Scale (NRS) pain scores at rest and with movement were recorded on postoperative days 0-3, 7, 14, and 30. Patients were sent a survey to assess chronic pain at months 22-66, which was examined as a single-group post hoc analysis. Based on the responses, patients were either classified into the CPSP or non-CPSP patient group. Chronic postsurgical pain was defined as an NRS score ≥ 4 with movement and the presence of resting pain. The primary outcome was a change in NRS. There were no differences in NRS pain scores with movement in the first 30 days postoperatively between patients with CPSP and without CPSP. Each unit increase in resting pain on postoperative days 3 and 14 was associated with significantly greater odds of CPSP presence (OR = 1.52; OR = 1.61, respectively), with a trend towards greater odds of CPSP at days 7 and 30 (OR = 1.33; OR = 1.43, respectively). We found that very intense pain in the initial phase seems to be related to the development of CPSP after TKA.

Peripheral Nerve Stimulation After Total Knee Arthroplasty and Non-Operable Patella Fracture

Chronic knee pain, affecting over 25% of adults in the United States, has surged by 65% over the past two decades leading to rising functional deficits, mobility problems, and a diminished quality of life. While conservative management with pharmacologic and minimally invasive injections are pursued early in the disease process, total knee arthroplasty for refractory osteoarthritis of the knee is often considered. This procedure usually improves pain and functionality within the first three months. However, a significant portion of patients often suffer from postoperative pain that can become chronic and debilitating. We detail the case of a patient with a previous TKA as well as a non-operable patella fracture who obtained significant relief with PNS despite prior conservative and minimally invasive management.

Postoperative pain trajectories in total hip arthroplasty

Aims

Total hip arthroplasty (THA) is a common procedure to address pain and enhance function in hip disorders such as osteoarthritis. Despite its success, postoperative patient recovery exhibits considerable heterogeneity. This study aimed to investigate whether patients follow distinct pain trajectories following THA and identify the patient characteristics linked to suboptimal trajectories.

Methods

This retrospective cohort study analyzed THA patients at a large academic centre (NYU Langone Orthopedic Hospital, New York, USA) from January 2018 to January 2023, who completed the Patient-Reported Outcomes Measurement Information System (PROMIS) pain intensity questionnaires, collected preoperatively at one-, three-, six-, 12-, and 24-month follow-up times. Growth mixture modelling (GMM) was used to model the trajectories. Optimal model fit was determined by Bayesian information criterion (BIC), Vuong-Lo-Mendell-Rubin likelihood ratio test (VLMR-LRT), posterior probabilities, and entropy values. Association between trajectory groups and patient characteristics were measured by multinomial logistic regression using the three-step approach.

Results

Among the 1,249 patients, a piecewise GMM model revealed three distinct pain trajectory groups: 56 patients (4.5%) in group 1; 1,144 patients (91.6%) in group 2; and 49 patients (3.9%) in group 3. Patients in group 2 experienced swift recovery post-THA and minimal preoperative pain. In contrast, groups 1 and 3 initiated with pronounced preoperative pain; however, only group 3 exhibited persistent long-term pain. Multinomial regression indicated African Americans were exceedingly likely to follow trajectory groups 1 (odds ratio (OR) 2.73) and 3 (OR 3.18). Additionally, odds of membership to group 3 increased by 12% for each BMI unit rise, by 19% for each added postoperative day, and by over four if discharged to rehabilitation services (OR 4.07).

Conclusion

This study identified three distinct pain trajectories following THA, highlighting the role of individual patient factors in postoperative recovery. This emphasizes the importance of preoperatively addressing modifiable risk factors associated with suboptimal pain trajectories, particularly in at-risk patients.

Ultrasound-guided thermal radiofrequency ablation of the genicular nerves after total knee replacement

The rate of refractory chronic pain after total knee replacement (TKR) is 20-25%, with no identifiable etiology in 6% of cases. Without an etiologic diagnosis, the surgeon is unlikely to consider revision, but pain poses a therapeutic challenge for achieving satisfaction and an acceptable quality of life. Genicular nerve radiofrequency ablation (GNRFA) was recently developed as a non-drug analgesic option. It is minimally invasive and safe, with few adverse effects, opening a new perspective for management of refractory chronic pain after TKR. LEVEL OF EVIDENCE: IV.

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.

Improvement in functional outcome 1 year after nonsurgical multidisciplinary treatment for chronic pain after total knee arthroplasty: A prospective cohort study

PURPOSE

The purpose of this study was to evaluate a multidisciplinary intervention developed for patients with debilitating chronic pain after total knee arthroplasty (TKA) unresponsive to existing treatment options.

METHODS

A treatment-based prospective cohort study was caried out in 30 TKA patients with debilitating chronic pain at least 1 year after TKA. The treatment was a multidisciplinary intervention. Main inclusion criteria: no indication for surgery. Primary outcome was function measured by KOOS-PS, OKS, OKS-APQ and WORQ. Secondary outcome measures were pain, fear of movement, self-efficacy, quality of life (QoL), health care and pain medication use, work rehabilitation and patient satisfaction. The assessments took place pre- and directly posttreatment, at 1, 3 and 12 months follow-up. The clinical relevance was assessed by predefined minimal important clinical change (MCIC).

RESULTS

At baseline patients were on average 64.7 (±7.9) years old, 67% were female, and they had knee pain for 42 (10-360) months. The results at 12-month follow-up: first, a significant improvement was shown in function, pain, fear of movement, self-efficacy and QoL. Second, in 38.5%-69.2% of patients clinical relevant improvement was shown for functional outcome, 31% for pain, and 50% for self-efficacy. Third, 42% of patients reported 'no healthcare use in the past three months'.

CONCLUSION

One year after a multidisciplinary treatment a clinically relevant improvement was shown in terms of function, pain, self-efficacy and QoL. It seems to be a promising treatment option in this difficult-to-treat patient group with debilitating chronic pain after TKA. Future research should examine the effect of the treatment in a larger study population, considering a control group, and focusing on the working population and evaluating cost-efficacy.

LEVEL OF EVIDENCE

Level II.

Factors associated with pain and functional impairment five years after total knee arthroplasty: a prospective observational study

BACKGROUND

Few studies have evaluated the associations between preoperative factors and pain and physical function outcomes after total knee arthroplasty (TKA) from a mid-term perspective. Identification of such factors is important for optimizing outcomes following surgery. Thus, we examined the associations between selected preoperative factors and moderate to severe pain and pain-related functional impairment as measured using the Brief Pain Inventory (BPI), five years after TKA in patients with knee osteoarthritis.

METHODS

In this prospective observational study, all patients scheduled for primary unilateral TKA for osteoarthritis were consecutively recruited. Preoperative factors identified from previous meta-analyses were included to assess their associations with pain severity and pain-related functional impairment five years after TKA. Pain severity was the primary outcome, while pain-related functional impairment was the secondary outcome. The BPI was used to evaluate outcomes five years post-TKA. Statistically significant factors from univariate regressions were entered into a multiple logistic regression model to identify those with the strongest associations with pain severity or pain-related functional impairment five years after TKA.

RESULTS

A total of 136 patients were included, with a mean age of 67.7 years (SD 9.2) and a majority being female (68%). More severe preoperative pain (OR = 1.34, 95% CI [1.03 to 1.74]), more painful sites (OR = 1.28., 95% CI [1.01 to 1.63]), and more severe anxiety symptoms (OR = 1.14., 95% CI [1.01 to 1.28]) were associated with increased likelihood of moderate to severe pain five years after TKA surgery, while more severe osteoarthritis (OR = 0.13, 95% CI [0.03 to 0.61]) was associated with reduced likelihood of moderate to severe pain five years after TKA. More severe anxiety symptoms (OR = 1.25, 95% CI [1.08 to 1.46]) were also associated with increased likelihood of moderate to severe pain-related functional impairment five years after surgery, while male sex (OR = 0.23, 95% CI [0.05 to 0.98]) was associated with reduced likelihood of pain-related functional impairment five years after surgery.

CONCLUSION

The identified preoperative factors should be included in larger prognostic studies evaluating the associations between preoperative factors and mid-term pain severity and physical function outcomes after TKA surgery.

The Role of Genicular Radiofrequency Ablation in the Management of Persistent Pain after Total Knee Arthroplasty

Persistent pain is one of the most frequent complications following total knee arthroplasty (TKA) and can be devastating for the patient's quality of life. The use of genicular nerve radiofrequency ablation (GNRFA) is prevalent regarding non-surgical treatment of knee osteoarthritis. However, it is controversial when employed for the management of residual pain after TKA. This study aims to evaluate the efficacy of GNRFA for the treatment of post-TKA chronic pain and to assess the potential benefits of its use. Twelve patients sustaining chronic pain after TKA underwent GNRFA treatment. The intervention included the superior medial genicular nerve, the superior lateral genicular nerve and the inferior medial genicular nerve. Visual analog scale (VAS) system was utilized for pain assessment at 1-week, 6-month, and 1-year follow-ups. Patients experiencing chronic knee pain derived from other or unspecified causes were excluded. Mean VAS score before the treatment was 8.3, while it ended up 2.3, 5.7, and 7.9 at the 1-week, 6-month, and 1-year follow-up, respectively. Some patients reported residual pain that they regarded more bearable than before the procedure at the 1-week evaluation, with no significant alterations in the 6-month reassessment. In 2 cases results at the 1-week follow-up were dissatisfying, however, this aided us in distinguishing the cause of the persistent pain. We were not able to conclude that GNRFA used for the treatment of chronic pain after TKA is as efficacious as in knee osteoarthritis pain. However, in some cases, it proved to be beneficial regarding discerning the etiology of the pain.

Postoperative Psychological Predictors for Chronic Postsurgical Pain After a Knee Arthroplasty: A Prospective Observational Study

OBJECTIVE

Chronic postsurgical pain (CPSP) is a significant adverse effect shown in around 20% of people who had undergone a knee arthroplasty (KA). Psychological risk factors have emerged as significant and potentially modifiable risk factors for its development. However, there is still little evidence when assessing these factors during the acute postoperative period. This study aimed to assess the predictive value of postoperative pain catastrophizing, pain-related fear of movement, anxiety, depression, and pain attitudes in developing CPSP after KA.

METHODS

A 6-month follow-up prospective observational study design was used. The study sample comprised 115 people who underwent a KA due to painful primary osteoarthritis. Measures of pain catastrophizing, pain-related fear of movement, anxiety, depression, and pain attitudes were obtained 1 week after surgery. CPSP was set at an intensity of ≥30 using a 100-mm visual analog scale at 3 and 6 months after surgery.

RESULTS

Analysis revealed that baseline pain intensity, pain catastrophizing, pain-related fear of movement, anxiety, depression, and maladaptive pain attitudes were significant predictors of chronic pain at 3 and 6 months after surgery in a univariate analysis. However, at 3 months after surgery, only pain intensity and pain catastrophizing were predictors in the final multivariate model forecasting disturbing pain. Moreover, 6 months after surgery, pain intensity and distrust in medical procedures remained independent predictors. Most of the psychological factors can be grouped into a single dimension defined as pain-related psychological distress.

CONCLUSION

The results suggest that postoperative pain intensity, pain catastrophizing, and pain attitudes are independent predictors for CPSP after KA.

IMPACT

Postoperative cognitive and emotional factors should be considered alongside pain intensity during postoperative rehabilitation after KA because they could influence the development of CPSP.

Effects of Electromyographic Biofeedback-Assisted Exercise on Functional Recovery and Quality of Life in Patients after Total Hip Arthroplasty: A Randomized Controlled Trial

The goal of the trial was to examine the effects of adding electromyographic biofeedback (EMG-BF) to the conventional program of physiotherapy after total hip arthroplasty (THA) on functional recovery and quality of life. The trial was designed as a prospective, interventional, single-blinded randomized controlled study. Ninety patients were randomized into an experimental group (EG) (n = 45; mean age 63.9 ± 8.8) and control group (CG) (n = 45; mean age 63.9 ± 9). All patients received 21 days of physiotherapy which consisted of therapeutic exercise (land-based and aquatic), electrotherapy, and education. Electromyographic biofeedback was added to a portion of the land-based exercise in EG. The Hip Disability and Osteoarthritis Outcome Score (HOOS), Numeric Rating Scale (NRS), Short Form Health Survey-36 (SF-36), use of a walking aid, 30 s chair stand test (CST) as well as the Timed Up and Go (TUG) test were used for outcome measurement. A higher proportion of the participants in both groups did not need a walking aid after the intervention (p < 0.05). All participants improved their 30 s CST and TUG results (p < 0.001), as well as their NRS and HOOS scores (p < 0.05). No significant differences between the groups were found. There were no additional benefits from adding EMG-BF to the conventional physiotherapy protocol.

Severe Postoperative Pain in Total Knee Arthroplasty Patients: Risk Factors, Insights and Implications for Pain Management via a Digital Health Approach

Up to 25% of patients undergoing knee arthroplasty report chronic pain postoperatively. Early identification of high-risk individuals can enhance pain management strategies. This retrospective analysis investigates the incidence of severe postoperative pain and its associated risk factors among 740 patients who underwent total knee arthroplasty. Utilizing a digital application, patients provided comprehensive data encompassing pre- and postoperative pain levels, analgesic usage, and completed a chronic pain risk assessment. Participants were categorized into two distinct groups based on their pain status at three months post-op: Group D+ (14%), characterized by pain scores exceeding 40/100 and/or the utilization of level 2 or 3 analgesics, and Group D- (86%), who did not meet these criteria. An analysis of pain trajectories within these groups revealed a non-linear progression, with specific patterns emerging amongst those predisposed to chronic pain. Notably, patients with a trajectory towards chronic pain exhibited a plateau in pain intensity approximately three weeks post-surgery. Significant preoperative risk factors were identified, including elevated initial pain levels, the presence of comorbidities, pain in other body areas, heightened joint sensitivity and stiffness. This study highlights the utility of digital platforms in enhancing patient care, particularly through the continuous monitoring of pain. Such an approach facilitates the early identification of potential complications and enables timely interventions.

Peripheral nerve stimulation for chronic knee pain following total knee arthroplasty: a systematic review

Chronic knee pain following total knee arthroplasty (TKA) affects a subset of patients that is refractory to pharmacological and non-pharmacological modalities. Peripheral nerve stimulation (PNS) has been used in patients with chronic knee pain following TKA and has shown some efficacy. Methods: Comprehensive search of Ovid Medline, Elsevier Embase, Cochrane Central Register of Controlled Trials, CINAHL Plus with Full Text, Scopus, SPORTDiscus with Full Text and the Web of Science platform. From inception to August 2022, for studies using PNS to treat chronic knee pain following TKA. Primary outcomes included pain scores, functional status and medication usage. Results: Nine studies were extrapolated with all demonstrating effectiveness of PNS for patients with chronic knee pain following TKA. Discussion: PNS for chronic knee pain following TKA has been shown to be an efficacious treatment modality. The level of evidence is low and more research is needed to assess its safety and effectiveness.

UK robotic arthroplasty clinical and cost effectiveness randomised controlled trial for hips (RACER-Hip): a study protocol

INTRODUCTION

The number of robotic-assisted hip replacement procedures has expanded globally with the intended aim of improving outcomes. Intraoperative robotic-arm systems add additional costs to total hip replacement (THR) surgery but may improve surgical precision and could contribute to diminished pain and improved function. Additionally, these systems may reduce the need for expensive revision surgery. Surgery with conventional instruments may be just as successful, quick and affordable. There is timely demand for a robust evaluation of this technology.

METHODS AND ANALYSIS

The Robotic Arthroplasty Clinical and cost Effectiveness Randomised controlled trial for Hips (RACER-Hip) is a multicentre (minimum of six UK sites), participant-assessor blinded, randomised controlled trial. 378 participants with hip osteoarthritis requiring THR will be randomised (1:1) to receive robotic-assisted THR, or THR using conventional surgical instruments. The primary outcome is the Forgotten Joint Score at 12 months post-randomisation; a patient-reported outcome measure assessing participants' awareness of their joint when undertaking daily activities. Secondary outcomes will be collected post-operatively (pain, blood loss and opioid usage) and at 3, 6, 12, 24 months, then 5 and 10 years postrandomisation (including function, pain, health-related quality of life, reoperations and satisfaction). Allocation concealment will be accomplished using a computer-based randomisation procedure on the day of surgery. Blinding methods include the use of sham incisions for marker clusters and blinded operation notes. The primary analysis will adhere to the intention-to-treat principle. Results will adhere to Consolidated Standards of Reporting Trials statements.

ETHICS AND DISSEMINATION

The trial was approved by an ethics committee (Solihull Research Ethics Committee, 30 June 2021, IRAS: 295831). Participants will provide informed consent before agreeing to participate. Results will be disseminated using peer-reviewed journal publications, presentations at international conferences and through the use of social media. We will develop plans to disseminate to patients and public with our patient partners.

TRIAL REGISTRATION NUMBER

ISRCTN13374625.

Continuity of primary care and emergency department visits following knee and hip replacement surgery: a retrospective cohort study

BACKGROUND

Continuity of primary care (CPC) improves patient well-being, but the association between CPC and surgical outcomes has not been well studied. The numbers of joint replacement procedures are expected to rise considerably in the coming years, so it is crucial to identify factors related to successful outcomes. The purpose of this study was to examine the association between CPC and emergency department (ED) visits after knee and hip replacement surgery.

METHODS

Physician claims and hospital data from 2005 to 2020 in Nova Scotia were used in this retrospective study. To measure CPC, we used the Modified Modified Continuity Index (MMCI), which is the number of primary care providers adjusted for the total number of visits. The outcome was ED visits within 90 days of discharge. Logistic regression was used to test for associations between MMCI and the probability of an ED visit.

RESULTS

There were 28 574 knee and 16 767 hip procedures in the data set; 13.9% (95% confidence interval [CI] 13.5%-14.3%) and 13.5% (95% CI 13.0%-14.0%) of the patients, respectively, had an ED visit within 90 days. For patients who underwent knee procedures, the mean MMCI was 0.868 (95% CI 0.867-0.870); 10.7% (95% CI 10.4 %-11.1 %) had perfect continuity of care. For patients who underwent hip procedures, the corresponding measures were 0.864 (95% CI 0.862-0.866) and 13.5% (95% CI 13.0%-14.0%). There was a statistically significant negative association between greater continuity of care and the probability of an ED visit after controlling for confounders.

CONCLUSION

Having multiple primary care providers before surgery increased the likelihood of negative outcomes following knee or hip replacement surgery compared with having a single provider. Presurgical conversations should include primary care history to improve postsurgical outcomes.

Trajectory of chronic and neuropathic pain, anxiety and depressive symptoms and pain catastrophizing after total knee replacement. Results of a prospective, single-center study at a mean follow-up of 7.5 years

INTRODUCTION

A considerable number of patients are not satisfied after total knee replacement (TKR) because of persistent pain. This pain can also be neuropathic in origin. Both types of pain have a large impact on function and quality of life. Furthermore, the trajectory of anxiety and depressive symptoms and pain catastrophizing has rarely been studied after TKR surgery. The primary objective of this study was to define the trajectory of knee pain after primary TKR. The secondary objectives were to evaluate how neuropathic pain, anxiety and depressive symptoms and pain catastrophizing change over time.

METHODS

This prospective, single-center study included patients who underwent primary TKR for primary osteoarthritis between July 2011 and December 2012. Personal data (age, sex, body mass index, knee history, operated side, surgical approach, type of implant, operative time, and rehabilitation course) and the responses to seven questionnaires (Numerical pain rating scale, DN4-interview for neuropathic pain, Oxford Knee Scale, Hospital and Anxiety Depression Scale, Beck Depression Inventory, Patient Catastrophizing Scale and Brief Pain Inventory) were determined preoperatively, at 6 months postoperative and at a mean follow-up of 7.5 years.

RESULTS

Preoperatively, 129 patients (35 men, 94 women) filled out all the questionnaires. Subsequently, 32 patients were excluded because of incomplete responses at 6 months postoperative, 6 were excluded because they had undergone revision surgery, 11 patients were lost to follow-up and 5 patients had died. In the end, 65 patients were available for analysis (50% of the initial cohort) who were 74 years old on average at inclusion. Between the preoperative period and 6 months postoperative, pain (p<0.001), function (p<0.001), anxiety symptoms (p<0.001) and catastrophizing (p<0.001) had improved. Depressive symptoms did not change (p=0.63). Between 6 months postoperative and the latest follow-up, none of the parameters changed further (p>0.05). Of the 65 patients analyzed, 21% had chronic pain of undefined origin at 6 months postoperative and 26% had chronic pain at the end of follow-up, with 50% also having neuropathic pain. Preoperatively, 40% of the 65 patients had neuropathic pain, 30% at 6 months (p=0.27) and 18% at 7.5 years after TKR (p=0.01).

CONCLUSION

The number of patients who have chronic pain after TKR is considerable, especially since knee pain stabilized at 6 months postoperative. Early detection is vital to prevent the pain from becoming chronic, which makes it more difficult to treat. Half the patients with persistent pain also had neuropathic pain, which should be detected before surgery so the patients can be referred to a specialized pain management center. The presence of anxiety and depressive symptoms and pain catastrophizing is not a contraindication to TKR, but these patients should be referred to specialists for treatment before surgery.

LEVEL OF EVIDENCE

IV, prospective cohort study.

Current Approaches to Four Challenging Pain Syndromes

During a conference of pain specialists, some of the experts addressed the potential management of four prevalent but difficult painful conditions, namely, chronic postsurgical pain (CPSP), knee osteoarthritis, chest trauma, and facet joint arthropathy. In all cases, the conditions posed challenges in accurate diagnoses as well as safe, effective treatments, especially using locoregional blocks. It is not clear why some surgical patients develop CPSP and others do not, although some risk factors have been identified. More importantly, the transitional phase of pain from acute to chronic deserves greater scrutiny. It appears as if more aggressive and more effective perioperative and postoperative analgesia could help mitigate or possibly prevent CPSP. Knee osteoarthritis is prevalent but is often managed pharmacologically and then with joint replacement; many patients simply live with the condition which can be viewed as a disease of the entire joint. New approaches with intra-articular injections of hyaluronic acid, platelet-rich plasma, and botulinum toxin may provide safe, effective, and durable pain control. Chest trauma can be extremely painful and a source of morbidity, but its management tends to rely on watchful waiting and drug therapy. New approaches to regional nerve blocks can be beneficial and may reduce troublesome symptoms such as the inability to cough or clear the lungs. Facet joint arthropathy is very prevalent among older people but is not completely clarified. It may be the source of intense pain with limited management strategies. The role of nerve blocks in facet joint arthropathy is an important new addition to the armamentarium of pain management, particularly for geriatric patients.

Evolution of somatosensory processing signs after nociceptive targeted surgery in patients with musculoskeletal disorders: a systematic review

ABSTRACT

Surgery is often advised when conservative treatment fails in musculoskeletal pain conditions, but a substantial proportion still suffers chronic pain after surgery. Somatosensory processing system (SPS) signs were previously studied as potential predictors for chronic postsurgical pain, but results are inconsistent. Therefore, studying the evolution of SPS signs could be of added value. The aim was to summarize all studies that measured how SPS signs evolved after nociceptive targeted surgery in musculoskeletal disorders and to find preoperative, perioperative, and postoperative predictors for the evolution of these SPS signs. Data were summarized, and risk of bias and level of evidence and recommendation were determined. Twenty-one studies were included. Five scored a low, 3 a moderate, and 13 a high risk of bias. In general, no consistent evolution of SPS signs comparing preoperative and postoperative values and predictors for this evolution in musculoskeletal disorders could be found. In most cases, static quantitative sensory testing (QST) did not change or conflicting results were found. On the other hand, dynamic QST mostly improved after surgery. Worthfully mentioning is that worsening of SPS signs was only seen at a follow-up of <3 months after surgery, that conclusions are stronger when evaluating dynamic QST with a follow-up of ≥3 months after surgery, and that pain improvement postsurgery was an important predictor. Future high-quality research should focus on the evolution of SPS signs after nociceptive targeted surgery, accounting for pain improvement groups and focusing on preoperative, perioperative, and postoperative predictors of this evolution.

A prospective study of chronic postsurgical pain in elderly patients: incidence, characteristics and risk factors

BACKGROUND

Due to the continued growth of surgical procedures in older adults and the significant impact of chronic postsurgical pain (CPSP), it is crucial to improve our understanding of the occurrence of CPSP as well as the appropriate prevention and treatment. We therefore conducted this study to determine the incidence, characteristics and risk factors of CPSP in elderly patients at both 3 and 6 months after surgery.

METHODS

Elderly patients (aged ≥ 60 years) undergoing elective surgery in our institution between April 2018 and March 2020 were prospectively enrolled in this study. Data on demographics, preoperative psychological well-being, intraoperative surgical and anesthesia management, and acute postoperative pain intensity were collected. At 3 and 6 months after surgery, patients received telephone interview and completed the questionnaires regarding chronic pain characteristics, analgesic consumption, and interference of the pain with activities of daily living (ADL).

RESULTS

A total of 1065 elderly patients were followed up for 6 postoperative months and included in final analysis. At 3 and 6 months after operation, the incidence of CPSP was 35.6% [95% confidence interval (95% CI) 32.7 - 38.8%] and 21.5% (95% CI 19.0% - 23.9%), respectively. CPSP cause negative impacts on patient's ADL and most particularly on mood. Neuropathic features were found in 45.1% of the patients with CPSP at 3 months. At 6 months, 31.0% of those with CPSP reported that the pain had neuropathic features. Preoperative anxiety [3 months: Odds ratio (OR) 2.244, 95% CI 1.693 to 2.973; 6 months: OR 2.397, 95% CI 1.745 to 3.294], preoperative depression (3 months: OR 1.709, 95% CI 1.292 to 2.261; 6 months: OR 1.565, 95% CI 1.136-2.156), orthopedic surgery (3 months: OR 1.927, 95% CI 1.112 to 3.341; 6 months: OR 2.484, 95% CI 1.220 to 5.061), higher pain severity on movement within postoperative 24 h (3 months: OR 1.317, 95% CI 1.191 to 1.457; 6 months: OR 1.317, 95% CI 1.177 to 1.475) were associated with a higher risk for CPSP independently at both 3 and 6 months after surgery.

CONCLUSIONS

CPSP is a common postoperative complication in elderly surgical patients. Preoperative anxiety and depression, orthopedic surgery, and greater intensity of acute postoperative pain on movement are associated with an increased risk for CPSP. It should be kept in mind that developing psychological interventions to reduce anxiety and depression and optimizing the management of acute postoperative pain will be effective in reducing the development of CPSP in this population.

Wireless High-Frequency Peripheral Nerve Stimulation for Chronic Refractory Knee Pain Post-total Knee Replacement

The number of joint replacement surgeries, especially knee replacement surgeries, is rising with the rising geriatric population. Chronic unremitting knee pain post-total knee replacement surgery is a common phenomenon. Usually, the pain responds to conservative measures, including physical therapy and medical management. In some patients, the pain post-knee replacement surgery can be refractory and unremitting. In such scenarios, peripheral nerve stimulation, or neuromodulation, can be an effective option.

Do patient-reported outcome measures improve after aseptic revision total hip arthroplasty?

BACKGROUND

The purpose of this study was to determine patient-reported outcome measures (PROMs) changes in: (1) pain, function and global health; and (2) predictors of PROMs in patients undergoing aseptic revision total hip arthroplasty (rTHA) using a multilevel model with patients nested within surgeon.

METHODS

A prospective cohort of 216 patients with baseline and 1-year PROMs who underwent aseptic rTHA between January 2016 and December 2017 were analysed. The most common indication for rTHA was aseptic loosening, instability, and implant failure. The PROMs included in this study were HOOS Pain and HOOS Physical Function Short-form (PS), Veterans RAND-12 Physical Component Score (VR-12 PCS), and VR-12 Mental Component Score (MCS). Multivariable linear regression models were constructed for predicting 1-year PROMs.

RESULTS

Mean 1-year PROMs improvement for aseptic revisions were 30.4 points for HOOS Pain and 22.1 points for HOOS PS. Predictors of better pain relief were patients with higher baseline pain scores. Predictors of better 1-year function were patients with higher baseline function and patients with a posterolateral hip surgical approach during revision. Although VR-12 PCS scores had an overall improvement, nearly 50% of patients saw no improvement or had worse physical component scores. Only 30.7% of patients reported improvements in VR-12 MCS.

CONCLUSIONS

Overall, patients undergoing aseptic rTHA improved in pain and function PROMs at 1 year. Although global health assessment improved overall, nearly half of aseptic rTHA patients reported no change in physical/mental health status. The associations highlighted in this study can help guide the shared decision-making process by setting expectations before aseptic revision THA.

Trajectories of Pain and Function Outcomes up to 5 to 8 Years Following Total Knee Arthroplasty

BACKGROUND

There appears to be substantial variability in outcomes > 2 years following total knee arthroplasty (TKA) that is masked by whole group analyses. The goal of the study was to identify trajectories of pain and function outcomes up to 5 to 8 years post-TKA and to identify baseline factors that are associated with different trajectories of recovery.

METHODS

Baseline, 6-month, and 12-month pain and function data were collected in a previous study investigating predictors of outcome following primary TKA (n = 286), along with a variety of baseline predictor variables. The present study obtained pain and function data at 5 to 8 years following TKA in the same cohort (n = 201). Latent class linear mixed models were used to identify different classes of pain and functional trajectories over time. The extent to which differences across latent classes were explained by baseline predictor variables was determined.

RESULTS

Three classes of pain and two classes of function trajectory were identified. While most patients (84% to 93%) followed a trajectory that showed an initial rapid gain following surgery that was sustained through 5 to 8 years, both pain and function included at least one trajectory class that showed a meaningful change after 12 months. No predictor variables were significantly associated with either the pain or function classes.

CONCLUSIONS

Most patients follow a traditional trajectory of recovery in knee pain and function over 5 to 8 years. However, alternative trajectories are observed in an important minority of patients such that knee pain and function at 12 months after surgery does not always reflect outcomes at 5 to 8 years.

Factors associated with persistent postsurgical pain after total knee or hip joint replacement: a systematic review and meta-analysis

Studies have identified demographic, clinical, psychosocial, and perioperative variables associated with persistent pain after a variety of surgeries. This study aimed to perform a systematic review and meta-analysis of factors associated with persistent pain after total knee replacement (TKR) and total hip replacement (THR) surgeries. To meet the inclusion criteria, studies were required to assess variables before or at the time of surgery, include a persistent postsurgical pain (PPSP) outcome measure at least 2 months after a TKR or THR surgery, and include a statistical analysis of the effect of the risk factor(s) on the outcome measure. Outcomes from studies implementing univariate and multivariable statistical models were analyzed separately. Where possible, data from univariate analyses on the same factors were combined in a meta-analysis. Eighty-one studies involving 171,354 patients were included in the review. Because of the heterogeneity of assessment methods, only 44% of the studies allowed meaningful meta-analysis. In meta-analyses, state anxiety (but not trait anxiety) scores and higher depression scores on the Beck Depression Inventory were associated with an increased risk of PPSP after TKR. In the qualitative summary of multivariable analyses, higher preoperative pain scores were associated with PPSP after TKR or THR. This review systematically assessed factors associated with an increased risk of PPSP after TKR and THR and highlights current knowledge gaps that can be addressed by future research.

Function and employment after total hip replacement in older adults: A narrative review

The burden of osteoarthritis (OA) has increased steadily due to an aging population, increasing life expectancy, obesity and lifestyle factors. Total hip replacement has become one of the most prevalent and successful operations globally and it is projected that demand will continue to grow as the incidence of OA continues to increase. Patients undergoing the operation expect much-improved function and pain relief but also increasingly need to return to work postoperatively, especially given the growing demand for the procedure and the encouragement of older people to continue working by most governments in the developed world. This review provides an overview of function and employment outcomes after hip arthroplasty. Despite the generally good success rate, some patients do not attain good functional outcomes and it is important that we develop ways to identify these patients preoperatively. We describe the effect of demographic, clinical and other factors on functional outcomes, as well as trajectories of physical function and pain recovery beyond the first few weeks after total hip replacement. Regarding employment outcomes, many people in work preoperatively are likely to resume to work after recovery; however, patients feel that they lack guidance from clinicians about returning to work postoperatively. Our review encompasses factors associated with return to work, timing of return to work, and potential temporary or permanent limitations that people might experience at work depending on type of employment.

Prehabilitation before total knee arthroplasty: A systematic review on the use and efficacy of stratified care

BACKGROUND

Preoperative rehabilitation (hereafter called "prehabilitation") has been proposed as a potentially effective treatment to target preoperative risk factors to prevent insufficient outcome after total knee arthroplasty (TKA).

PURPOSE

We aimed to assess whether previous clinical trials of non-surgical, non-pharmacological prehabilitation in individuals with knee osteoarthritis (KOA) awaiting TKA focused on specific clinical phenotypes or specific individual characteristics and whether the content of the prehabilitation was stratified accordingly. Second, we aimed to summarize and compare the long-term effects of stratified and non-stratified care on pain, satisfaction, function and quality of life.

METHODS

A systematic literature search of PubMed, Web of Science, Scopus and Embase was performed. All relevant articles published up to April 19, 2021 reporting "(randomized controlled) clinical trials or prospective cohort studies" (S) related to the key words "total knee arthroplasty" (P), "preoperative conservative interventions" (I), "pain, function, quality of life and/or satisfaction" (O) were included.

RESULTS

After screening 3498 potentially eligible records, 18 studies were assessed for risk of bias. Twelve studies had low, 2 moderate, 3 serious, and one high risk of bias. The latter study was excluded, resulting in 17 included studies. Five studies investigated a"stratified prehabilitation care" and 12 "non-stratified prehabilitation care". Stratified prehabilitation in 4 studies meant that the study sample was chosen considering a predefined intervention, and in the fifth study, the prehabilitation was stratified to individuals' needs. No direct comparison between the 2 approaches was possible. We found weak evidence for a positive effect of biopsychosocial prehabilitation compared to no prehabilitation on function (stratified studies) and pain neuroscience education prehabilitation compared to biomedical education on satisfaction (non-stratified studies) at 6 months post-TKA. We found strong evidence for positive effects of exercise prehabilitation compared to no prehabilitation on pain at 6 months and on function at 12 months post-TKA (non-stratified studies).

CONCLUSION

More research is needed of stratified prehabilitation care focusing on individual characteristics in people with KOA awaiting TKA.

REGISTRATION NUMBER

This systematic review was prospectively registered at PROSPERO on March 22, 2021 (no. CRD42021221098).

The impact of waiting time for orthopaedic consultation on pain levels in individuals with osteoarthritis: a systematic review and meta-analysis

OBJECTIVE

Time spent waiting for access to orthopaedic specialist health services has been suggested to result in increased pain in individuals with osteoarthritis (OA). We assessed whether time spent on an orthopaedic waiting list resulted in a detrimental effect on pain levels in patients with knee or hip OA.

METHODS

We searched Ovid MEDLINE, EMBASE and EBSCOhost databases from inception until September 2021. Eligible articles included individuals with OA on an orthopaedic waitlist and not receiving active treatment, and reported pain measures at two or more time points. Random-effects meta-analysis was used to estimate the pooled effect of waiting time on pain levels. Meta-regression was used to determine predictors of effect size.

RESULTS

Thirty-three articles were included (n = 2,490 participants, 67 ± 3 years and 62% female). The range of waiting time was 2 weeks to 2 years (20.8 ± 18.8 weeks). There was no significant change in pain over time (effect size = 0.082, 95% CI = -0.009, 0.172), nor was the length of time associated with longitudinal changes in pain over time (β = 0.004, 95% CI = -0.005, 0.012). Body mass index was a significant predictor of pain (β = -0.043, 95% CI = -0.079, 0.006), whereas age and sex were not.

CONCLUSIONS

Pain remained stable for up to 1 year in patients with OA on an orthopaedic waitlist. Future research is required to understand whether pain increases in patients waiting longer than 1 year.

Chronic pain after surgery and trauma: current situation and future directions

Chronic post-surgical pain (CPSP) stands as a major health issue. The unchanged incidence over the last two decades underlines both the failure of predictive models developed until now and the lack of efficacy of common “preventive” strategies (pharmacotherapy and regional analgesic techniques) applied in current clinical practice. The recognition of CPSP as a disease and the release of a common definition of the condition is an important progress in the field. CPSP predictive scores exist but none has presently demonstrated an impact on patient care. New clinical directions based on the resolution of postoperative pain, a complex and highly dynamic process supported by individual pain trajectories, argue for predictive models and preventive strategies extended to the subacute pain period i.e. after hospital discharge.

How long do revised and multiply revised hip replacements last? A retrospective observational study of the National Joint Registry

Background

Hip replacements are common and effective operations but patients that undergo this intervention are at risk of the replacements failing, requiring costly and often complex revision surgery with poorer outcomes than primary surgery. There is paucity of reliable data examining the treatment pathway for hip replacements over the life of the patient in terms of risk of revision and re-revisions. We aim to provide detailed information on the longevity of hip revision surgery.

Methods

We did a retrospective observational registry-based study of the National Joint Registry, using data on hip replacements from all participating hospitals in England and Wales, UK. We included data on all first revisions, with an identifiable primary procedure, with osteoarthritis as the sole indication for the original primary procedure. Kaplan-Meier estimates were used to determine the cumulative probability of revision and subsequent re-revision after primary hip replacement. Analyses were stratified by age and gender, and the influence of time from first to second revision on the risk of further revision was explored.

Findings

Between April 1, 2003, and Dec 31, 2019, there were 29 010 revision hip replacements with a linked primary episode. Revision rates of revision hip replacements were higher in patients younger than 55 years than in older age groups. After revision of primary total hip replacement, 21·3% (95% CI 18·6-24·4) of first revisions were revised again within 15 years, 22·3% (20·3-24·4) of second revisions were revised again within 7 years, and 22·3% (18·3-27·0) of third revisions were revised again within 3 years. After revision of hip resurfacing, 23·7% (95% CI 19·6-28·5) of these revisions were revised again within 15 years, 21·0% (17·0-25·8) of second revisions were revised again within 7 years, and 19·3% (11·9-30·4) of third revisions were revised again within 3 years. A shorter time between revision episodes was associated with earlier subsequent revision.

Interpretation

Younger patients are at an increased risk of multiple revisions. Patients who undergo a revision have a steadily increasing risk of further revision the more procedures they undergo, and each subsequent revision lasts for approximately half the time of the previous one. Although hip replacements are effective for improving pain and function and usually last a remarkably long time, if they are revised, successive revisions are progressively and markedly less successful.

Funding

NIHR Biomedical Research Centre at the University Hospitals Bristol and Weston NHS Foundation Trust and the University of Bristol, Healthcare Quality Improvement Partnership; and the National Joint Registry.

Patient-reported outcome of 95% of young patients improves after primary total hip arthroplasty: identification of 3 recovery trajectories in 3,207 patients younger than 55 years from the Dutch Arthroplasty Register

BACKGROUND AND PURPOSE

Little is known about the outcome after receiving total hip arthroplasty (THA), specifically in young patients. We identified different recovery trajectories in young patients using data from the Dutch Arthroplasty Register (LROI). We also explored whether risk factors commonly associated with functional outcome were associated with recovery trajectory.

PATIENTS AND METHODS

We used HOOS-PS score data up to 1 year postoperatively from the LROI from all patients younger than 55 years who received a primary THA between 2014 and 2019. To investigate whether different recovery trajectories could be distinguished, we performed latent class growth analysis (LCGA). Subsequently, we used multinomial logistic regression analyses to explore factors associated with class membership.

RESULTS

3,207 patients were included. LCGA identified 3 groups of patients: optimal responders (75%), good responders (21%), and poor responders (4.7%). Female sex (RR 1.1; 95% CI 1.1-1.1), ASA II (RR 1.1; CI 1.0-1.1), ASA III-IV (RR 1.1; CI 1.0-1.2), smoking (RR 1.1; CI 1.0-1.1), cemented fixation (RR 1.2; CI 1.1-1.2), and a 22-28 mm head diameter (RR 1.1; CI 1.0-1.2) were associated with "good responder" class membership. ASA II (RR 1.1; 1.0-1.2), ASA III-IV (RR 1.2; 1.1-1.3), smoking (RR 1.2; CI 1.1-1.2), and hybrid fixation (RR 1.2; CI 1.0-1.2) were associated with "poor responder" class membership.

INTERPRETATION

3 recovery trajectories could be identified. Female sex, higher ASA classifications, smoking, cemented or hybrid fixation, and small head diameter were associated with a suboptimal result after primary THA in young patients. These findings can aid in the process to determine which patients are at risk of a suboptimal outcome.

Primary care consultations and pain medicine prescriptions: a comparison between patients with and without chronic pain after total knee replacement

BACKGROUND

Approximately 20% of patients experience chronic pain after total knee replacement (TKR). The impact of chronic pain after TKR on primary care services in the UK is currently unknown. The aim of this study was to compare primary care consultations and pain medicine prescriptions between patients with and without chronic pain after TKR.

METHODS

Data from 5,055 patients who received TKR between 2009 and 2016 with anonymised linked data from the Clinical Practice Research Datalink Gold (CPRD) and English Hospital Episode Statistics (HES) Patient Reported Outcome Measures (PROMs) programme were analysed. The exposure time was from 10 years pre-operative to eight years post-operative. Patients with a score ≤ 14 on the Oxford Knee Score pain component scale at 6 months post-operative were classified as having chronic pain after TKR. Primary care consultations and prescribed pain medicines were quantified, and costs calculated based on national cost data.

RESULTS

721 patients (14%) had chronic pain after TKR. The prevalence and costs of primary care consultations and pain medicine prescriptions per year were consistently higher for patients with chronic pain after TKR compared with those without chronic pain after TKR; these differences were observed both before and after surgery. There was a substantial and sustained increase in the cost of opioid prescriptions after surgery for patients with chronic pain after TKR, peaking at seven years post-operative.

CONCLUSIONS

Increased primary care consultations and pain medicine prescriptions associated with chronic pain after TKR represent a considerable financial cost to primary care services. Evaluation of interventions to reduce the risk of developing this pain condition and improve the early management of pain after TKR are needed to improve outcomes for patients and reduce costs to healthcare services.

Diagnosis of Central Sensitization and Its Effects on Postoperative Outcomes following Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

Central sensitization (CS) has been extensively researched as a cause of persistent pain after total knee arthroplasty (TKA). This systematic review study sought to investigate the diagnosis of CS in patients who underwent TKA for knee osteoarthritis (OA) and the effect of CS on clinical outcomes after TKA. Three comprehensive databases, including MEDLINE, EMBASE, and the Cochrane Library, were searched for studies that evaluated the outcomes of TKA in knee OA patients with CS. Data extraction, risk of bias assessment, and (where appropriate) meta-analysis were performed. The standardized mean difference (SMD) with a 95% confidence interval was used to assess the different scales of pain. A total of eight studies were selected, including two retrospective studies and five prospective observational studies. One study used additional randomized controlled trial data. Five studies were finally included in the meta-analysis. All studies had a minimum follow-up period of 3 months. The Central Sensitization Inventory (CSI), whole-body pain diagram, and quantitative sensory testing (QST) were used for measuring CS. The pooled analysis showed that patients with CS had more severe postoperative pain after TKA (SMD, 0.65; 95% CI, 0.40−0.90; p < 0.01) with moderate heterogeneity (I2 = 60%). In patients who underwent TKA with knee OA, CSI is most often used for the diagnosis of CS, and the QST and whole-body pain diagram are also used. CS is closely associated with more severe and persistent pain after TKA.

Experiences of recovery and a new care pathway for people with pain after total knee replacement: qualitative research embedded in the STAR trial

Background

Approximately 20% of people experience chronic postsurgical pain after total knee replacement. The STAR randomised controlled trial (ISCRTN92545361) evaluated the clinical- and cost-effectiveness of a new multifaceted and personalised care pathway, compared with usual care, for people with pain at three months after total knee replacement. We report trial participants’ experiences of postoperative pain and the acceptability of the STAR care pathway, which consisted of an assessment clinic at three months, and up to six follow-up telephone calls over 12 months.

Methods

Semi-structured interviews were conducted with 27 people (10 men, 17 women) between February 2018 and January 2020. Participants were sampled purposively from the care pathway intervention group and interviewed after completion of the final postoperative trial questionnaire at approximately 15 months after knee replacement. Interviews were audio-recorded, transcribed, anonymised and analysed using inductive thematic analysis.

Findings

Many participants were unprepared for the severity and impact of postoperative pain, which they described as extreme and constant and that tested their physical and mental endurance. Participants identified ‘low points’ during their recovery, triggered by stiffening, pain or swelling that caused feelings of anxiety, depression, and pain catastrophising. Participants described the STAR assessment clinic as something that seemed “perfectly normal” suggesting it was seamlessly integrated into NHS care. Even in the context of some ongoing pain, the STAR care pathway had provided a source of support and an opportunity to discuss concerns about their ongoing recovery.

Conclusions

People who have knee replacement may be unprepared for the severity and impact of postoperative pain, and the hard work of recovery afterwards. This highlights the challenges of preparing patients for total knee replacement and suggests that clinical attention is needed if exercise and mobilising is painful beyond the three month postoperative period. The STAR care pathway is acceptable to people with pain after total knee replacement.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05423-5.

Immediate Postoperative Improvement in Gait Parameters following Primary Total Knee Arthroplasty Can Be Measured with an Insole Sensor Device

Total knee arthroplasty (TKA) improves the quality of life in those suffering from debilitating arthritis of the knee. However, little is known about the influence of TKA on restoring physical function. Prior studies have used artificial means, such as instrumented treadmills, to assess physical function after TKA. In this study an insole sensor device was used to quantify parameters of gait. The purpose of this study was to evaluate the ability of a wearable insole sensor device to measure immediate postoperative gait parameters at 2 weeks and 6 weeks following primary TKA and to determine if the device was suitable and sensitive enough to identify and measure potentially subtle changes in these measures at these early postoperative time periods. Twenty-nine patients with unilateral TKA, without contralateral knee pain, and aid-free walking before surgery were evaluated. An insole force sensor measured the postoperative parameters while walking a distance of 40 m on level ground at 2 and 6 weeks after TKA. The loading rate of the operated lower extremity was an average of 68.7% of the contralateral side at 2 weeks post-surgery and increased to 82.1% at 6 weeks post-surgery (p < 0.001). The mean gait speed increased from 0.75 to 1.02 m/s, (p < 0.001) and cadence increased from 82.9 to 99.9 steps/min (p < 0.001), while the numeric pain scale at rest decreased from 3.5/10 to 2.2/10, (p < 0.001) and the pain while walking from 3.9/10 to 2.4/10, (p < 0.001) from 2 to 6 weeks post-surgery. A significant improvement in gait parameters is detectable in the first 6 weeks after surgery with the use of a wearable insole device. As the gait speed and cadence increase and the VAS pain level decreases, the loading rate and average peak force begin to normalize. This device may allow for early gait analysis and have potential clinical utility in detecting early differences in patients' functional status following TKA.

Progression of chronic pain and associated health-related quality of life and healthcare resource use over 5 years after total knee replacement: evidence from a cohort study

OBJECTIVE

As part of the STAR Programme, a comprehensive study exploring long-term pain after surgery, we investigated how pain and function, health-related quality of life (HRQL), and healthcare resource use evolved over 5 years after total knee replacement (TKR) for those with and without chronic pain 1 year after their primary surgery.

METHODS

We used data from the Clinical Outcomes in Arthroplasty Study prospective cohort study, which followed patients undergoing TKR from two English hospitals for 5 years. Chronic pain was defined using the Oxford Knee Score Pain Subscale (OKS-PS) where participants reporting a score of 14 or lower were classified as having chronic pain 1-year postsurgery. Pain and function were measured with the OKS, HRQL using the EuroQoL-5 Dimension, resource use from yearly questionnaires, and costs estimated from a healthcare system perspective. We analysed the changes in OKS-PS, HRQL and resource use over a 5-year follow-up period. Multiple imputation accounted for missing data.

RESULTS

Chronic pain was reported in 70/552 operated knees (12.7%) 1 year after surgery. The chronic pain group had worse pain, function and HRQL presurgery and postsurgery than the non-chronic pain group. Those without chronic pain markedly improved right after surgery, then plateaued. Those with chronic pain improved slowly but steadily. Participants with chronic pain reported greater healthcare resource use and costs than those without, especially 1 year after surgery, and mostly from hospital readmissions. 64.7% of those in chronic pain recovered during the following 4 years, while 30.9% fluctuated in and out of chronic pain.

CONCLUSION

Although TKR is often highly beneficial, some patients experienced chronic pain postsurgery. Although many fluctuated in their pain levels and most recovered over time, identifying people most likely to have chronic pain and supporting their recovery would benefit patients and healthcare systems.

Preoperative Factors and Patient-Reported Outcomes After Total Hip Arthroplasty: Multivariable Prediction Modeling

BACKGROUND

Although total hip arthroplasty (THA) has been established as a cost-effective intervention, some patients experience ongoing pain and dissatisfaction. There is interest in predicting postoperative outcomes based on preoperative data, but the relative contribution of different preoperative factors is unclear. The study's aim was to develop multivariable prediction models for the assessment of patient-reported outcomes.

METHOD

Registry data on 1412 patients undergoing THA for osteoarthritis at two hospitals between 2013 and 2018 was used. Potential predictors included age, sex, body mass index, spoken language, education level, previous THA, American Society of Anaesthesiologists (ASA) score, lower back pain, depression/anxiety, other lower limb arthritis, number of other comorbidities, the preoperative expectation of pain and function, EuroQol Visual Analogue Scale (EQ-VAS) and preoperative OHS. Radiographic scores were also used: joint space narrowing (JSN), osteophytes, sclerosis, and an overall grade based on the Kellgren-Lawrence (KL) classification. Outcomes assessed were the patient-rated improvement, satisfaction, and OHS at six months.

RESULTS

JSN or overall KL scores were the most important predictors (P < .001) for all outcomes, with better radiographic scores associated with worse outcomes. Other predictors associated with poorer outcomes were lower back pain and lower expectation (predicting poor improvement), lower education and higher ASA (predicting lower satisfaction) and younger age, female sex, non-English speakers, lower preoperative EQ-VAS, lower education, back pain, and anxiety/depression (predicting lower OHS).

CONCLUSION

Preoperative radiological scores are an important predictor of patient-reported outcomes at six months postoperatively. Understanding the relative strengths and significance of different factors in predicting outcomes will help the clinician and patient decision-making for THA.

MRI for an Acute Secondary Site Complication in Post-arthroplasty Management: Narrative Review of Safety Concerns for an Implanted Hip and Knee Joint

Arthroplasty in the elderly may present with acute or late-onset complications unrelated to an implanted arthroplasty joint. Magnetic resonance imaging (MRI) evaluation of an acute onset complication in the immediate post-arthroplasty scenario presents safety concerns. An arthroplasty surgeon's dilemma relates to the loosening, heating, or migration of implanted hip or knee joints.

We present a representational case scenario for discussion. A hip arthroplasty patient presenting with hemiplegia in the immediate postoperative period necessitated an MRI evaluation for the brain with an additional angiogram. A knee arthroplasty patient presenting with lower limb weakness in the immediate postoperative period necessitated an MRI evaluation of the brain. Loosening of surgical metallic clips used for wound closure and the instability or loosening of recently implanted hip and knee joints pose significant safety concerns for the arthroplasty surgeon. The confirmatory diagnosis of the secondary site complication in the acute post-arthroplasty perioperative period, however, allowed the allied super-specialist to plan the management protocol.

A review of the literature suggests that the use of nonferromagnetic elements in implanted joints with the use of cement or the press-fit method of implantation during arthroplasty has high safety margins. The staples used for wound closure have significant strength to hold the wound without any disruption or dehiscence during the MRI imaging. The metallic artifacts associated with an implanted joint do not interfere in the evaluation of the secondary site MRI.

MRI can be safely done in a well-fixed joint of non-ferromagnetic elements. The review of literature also suggests that MRI can be done even in the presence of skin staples for the assessment of an acute secondary site complication in a post-arthroplasty patient. The risk-to-benefit ratio though needs to be applied for imaging a secondary site.

Safety and Efficacy of Genicular Nerve Radiofrequency Ablation for Management of Painful Total Knee Replacement: A Systematic Review

Painful total knee replacement (TKR) without an obvious underlying identifiable pathology is not uncommon. Dissatisfaction after TKR can be up to 20%. Different treatment modalities, including non-operative and operative procedures, have been described in the literature. Radiofrequency ablation of genicular nerves (GNRFA) is emerging as a newer treatment modality for painful TKR without an obvious underlying identifiable pathology. Despite a modest number of publications demonstrating the usefulness of GNRFA in managing pain in knee osteoarthritis, the efficacy of GNRFA has not been completely established in the management of residual pain after TKR. This systematic review aimed to analyze all published studies (nine studies) on GNRFA as an option to manage residual pain after TKR. Based on this current systematic review, we noted that GNRFA is a modality to treat post residual pain and patients can anticipate improvement in pain up to three months with minimal complications. This article provides an overview of the currently available knowledge and techniques employed for this procedure, as well as the expected outcome and safety profile of GNRFA in painful TKR.

Peripheral Nerve Stimulation of the Saphenous and Superior Lateral Genicular Nerves for Chronic Pain After Knee Surgery

Total knee arthroplasty (TKA) is one of the most commonly conducted surgeries in the United States. Typically, TKA is conducted to relieve pain from patients with long-standing osteoarthritis. Postoperative knee pain is a common issue after TKA. For some patients, postoperative knee pain exceeds the normal 3-6-month phase and becomes chronic. Pain is typically managed with the use of medications and physical therapy. In this case, we describe the use of peripheral nerve stimulation (PNS) of the saphenous and superior lateral genicular nerves for a patient experiencing chronic postoperative knee pain utilizing SPRINT PNS technology.

Surgery-related predictors of kneeling ability following total knee arthroplasty: a systematic review and meta-analysis

Purpose

Kneeling ability is among the poorest outcomes following total knee arthroplasty (TKA). The purpose of this meta-analysis was to: (1) quantify kneeling ability after TKA; (2) identify surgical approaches and prosthesis designs that improve kneeling ability following TKA; and (3) quantify the effectiveness of these approaches.

Methods

We performed a systematic review in accordance with the PRISMA guidelines of multiple medical databases. Data relating to demographics, TKA technique, prosthesis design, and kneeling-specific outcomes were extracted. Comparative outcomes data were pooled using a random effects model.

Results

Thirty-six studies met the eligibility criteria. The proportion of patients able to kneel increased with longer follow-up (36.8% at a minimum of 1 year follow-up versus 47.6% after a minimum of 3 years follow-up, p < 0.001). The odds of kneeling were greater for patients undergoing an anterolateral incision compared with an anteromedial incision (OR 3.0, 95% CI 1.3–6.9, p = 0.02); a transverse incision compared with a longitudinal incision (OR 3.5, 95% CI 1.4–8.7, p = 0.008); and a shorter incision compared with a longer incision (OR 8.5, 95% CI 2.3–30.9, p = 0.001). The odds of kneeling were worse for a mobile prosthesis compared with a fixed platform design (OR 0.3, 95% CI 0.1–0.7, p = 0.005).

Conclusion

A large majority of patients are unable to kneel following TKA, although the ability to kneel improves over time. This evidence may facilitate preoperative patient counseling. Variations in choice of incision location and length may affect ability to kneel; however, high-quality randomized trials are needed to corroborate our findings.

The effect of surgical approach in total knee replacement on outcomes. An analysis of 875,166 elective operations from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man

BACKGROUND

Total knee replacement (TKR) is clinically and cost-effective. The surgical approach employed influences the outcome, however there is little generalisable and robust evidence to guide practice. We compared outcomes between the common primary TKR surgical approaches.

METHODS

875,166 primary TKRs captured in the National Joint Registry, linked to hospital inpatient, mortality and patient reported outcome measures (PROMs) data, with up to 15.75 years follow-up were analysed. There were 10 surgical approach groups: medial parapatellar, midvastus, subvastus, lateral parapatellar, 'other' and their minimally invasive versions. Survival methods were used to compare revision rates and 45-day mortality. Groups were compared using Cox proportional hazards regression and Flexible Parametric Survival Modelling (FPM). Confounders included age at surgery, sex, risk group (indications additional to osteoarthritis), American Society of Anesthesiologists grade, TKR fixation, year of primary, body mass index, and for mortality, deprivation and Charlson comorbidity subgroups. PROMs were analysed with regression modelling or non-parametric methods.

RESULTS

The conventional midvastus approach was associated with lower revision rates (Hazard Rate Ratio (HRR) 0.80 (95% CI 0.71-0.91) P = 0.001) and the lateral parapatellar with higher revision rates (HRR 1.35 (95% CI 1.12-1.63) P = 0.002) compared to the conventional medial parapatellar approach. Mortality rates were similar between approaches. PROMs showed statistically significant, but not clinically important, differences.

CONCLUSIONS

There is little difference in PROMs between the various surgical approaches in TKR with all resulting in good outcomes. However, the conventional midvastus approach (used in 3% of cases) was associated with a 20% reduced risk of revision surgery compared to the most commonly used knee approach (the conventional medial parapatellar: used in 91.9% of cases). This data supports the use of the midvastus approach and thus surgeons should consider utilising this approach more frequently. Minimally invasive approaches did not appear to convey any clinical advantage in this study over conventional approaches for primary TKR.

Is There an Association Between Negative Patient-Experience Comments and Perioperative Outcomes After Primary Total Hip Arthroplasty?

BACKGROUND

Multiple stakeholders are interested in improving patient experience after primary total hip arthroplasty due to shifts toward patient-centered care. Patient free-text narratives are a potentially valuable but largely unexplored source of data.

METHODS

The records of 383 patients who underwent primary total hip arthroplasty between August 2016 and August 2019 were combined with vendor-supplied patient satisfaction data, which included patient free-text comments and the Press Ganey satisfaction survey. A total of 1295 patient comments were analyzed for sentiment, and negative comments were categorized into nine themes. Postoperative outcomes, patient-reported outcome measures, and traditional measures of satisfaction were compared between patients who provided a negative comment vs those who did not. Multivariable regression was used to determine perioperative variables associated with providing a negative comment.

RESULTS

Of the 1295 patient comments: 54% were positive, 24% were negative, 10% were mixed, and 12% were neutral. Top two themes of negative comments were room condition (25%) and inefficient communication (23%). There were no differences in studied outcomes (eg. peak pain intensity, length of stay, or improvements in hip injury and osteoarthritis outcome scores Jr. and pain visual analog scale scores at 6-week follow-up) between those who provided negative comments vs those who did not (P > .05). However, patients who made negative comments were less likely to recommend their hospital care to peers (P < .001). Finally, patients who had >2 allergies (P = .024) were more likely to provide negative comments.

CONCLUSION

The present study demonstrates that patient satisfaction appears not to be a reliable sole proxy for traditional objective outcome measures of pain relief and functional improvement.

AAAPT: Assessment of the Acute Pain Trajectory

OBJECTIVE

Define and contrast acute pain trajectories vs. the aggregate pain measurements, summarize appropriate linear and nonlinear statistical analyses for pain trajectories at the patient level, and present methods to classify individual pain trajectories. Clinical applications of acute pain trajectories are also discussed.

SETTING

In 2016, an expert panel involving the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION), American Pain Society (APS), and American Academy of Pain Medicine (AAPM) established an initiative to create a pain taxonomy, named the ACTTION-APS-AAPM Pain Taxonomy (AAAPT), for the multidimensional classification of acute pain. The AAAPT panel commissioned the present report to provide further details on analysis of the individual acute pain trajectory as an important component of comprehensive pain assessment.

METHODS

Linear mixed models and nonlinear models (e.g., regression splines and polynomial models) can be applied to analyze the acute pain trajectory. Alternatively, methods for classifying individual pain trajectories (e.g., using the 50% confidence interval of the random slope approach or using latent class analyses) can be applied in the clinical context to identify different trajectories of resolving pain (e.g., rapid reduction or slow reduction) or persisting pain. Each approach has advantages and disadvantages that may guide selection. Assessment of the acute pain trajectory may guide treatment and tailoring to anticipated symptom recovery. The acute pain trajectory can also serve as a treatment outcome measure, informing further management.

CONCLUSIONS

Application of trajectory approaches to acute pain assessments enables more comprehensive measurement of acute pain, which forms the cornerstone of accurate classification and treatment of pain.

Implementing fast-track in total hip arthroplasty: rapid mobilization with low need for pain medication and low pain values : Retrospective analysis of 102 consecutive patients

Introduction

Total hip arthroplasty (THA) is reported to be one of the most painful surgical procedures. Perioperative management and rehabilitation patterns are of great importance for the success of the procedure. The aim of this cohort study was the evaluation of function, mobilization and pain scores during the inpatient stay (6 days postoperatively) and 4 weeks after fast-track THA.

Materials and methods

A total of 102 consecutive patients were included in this retrospective cohort trial after minimally invasive cementless total hip arthroplasty under spinal anesthesia in a fast-track setup. The extent of mobilization under full-weight-bearing with crutches (walking distance in meters and necessity of nurse aid) and pain values using a numerical rating scale (NRS) were measured. Function was evaluated measuring the range of motion (ROM) and the ability of sitting on a chair, walking and personal hygiene. Furthermore, circumferences of thighs were measured to evaluate the extent of postoperative swelling. The widespread Harris Hip Score (HHS) was used to compare results pre- and 4 weeks postoperatively.

Results

Evaluation of pain scores in the postoperative course showed a constant decrease in the first postoperative week (days 1–6 postoperatively). The pain scores before surgery were significantly higher than surgery (day 6), during mobilization (p < 0.001), at rest (p < 0.001) and at night (p < 0.001). All patients were able to mobilize on the day of surgery. In addition, there was a significant improvement in independent activities within the first 6 days postoperatively: sitting on a chair (p < 0.001), walking (p < 0.001) and personal hygiene (p < 0.001). There was no significant difference between the measured preoperative and postoperative (day 6 after surgery) thigh circumferences above the knee joint. Compared to preoperatively, there was a significant (p < 0.001) improvement of the HHS 4 weeks after surgery. In 100% of the cases, the operation was reported to be successful and all of the treated patients would choose a fast-track setup again.

Conclusion

Application of a fast-track scheme is effective regarding function and mobilization of patients. Low pain values and rapid improvement of walking distance confirms the success of the fast-track concept in the immediate postoperative course. Future prospective studies have to confirm the results comparing a conventional and a fast-track pathway.

Natural Language Processing of Patient-Experience Comments After Primary Total Knee Arthroplasty

BACKGROUND

There is interest in improving patient experience after total knee arthroplasty (TKA) due to recent shifts toward value-based medicine. Patient narratives are a valuable but unexplored source of information.

METHODS

Records of 319 patients who had undergone primary TKA between August 2016 and August 2019 were linked with vendor-supplied patient satisfaction data, which included patient comments and the Press Ganey satisfaction survey. Using machine-learning-based natural language processing, 1048 patient comments were analyzed for sentiment and classified into themes. Postoperative outcomes, patient-reported outcome measures, and traditional measures of satisfaction were compared between patients who provided a negative comment vs those who did not (positive, neutral, mixed grouped together). Multivariable regression was used to determine perioperative variables associated with providing a negative comment.

RESULTS

Of the 1048 patient comments, 25% were negative, 58% were positive, 8% were mixed, and 9% were neutral. Top 2 themes of negative comments were room condition (25%) and inefficient communication (23%). There were no differences in most of the studied outcomes (eg, peak pain intensity, length of stay, or Knee Injury and Osteoarthritis Outcome Score Junior and pain scores at 6-week follow-up) between the 2 cohorts (P > .05). However, patients who made negative comments were less likely to highly recommend their hospital care to peers (P < .001). Finally, patients who had higher American Society of Anesthesiologists Score and those who received a scopolamine patch were more likely to provide negative comments (P < .05).

CONCLUSION

Although the current study showed that patient satisfaction might not be a proxy for traditional objective perioperative outcomes, efforts to improve the nontechnical aspects of medicine are still crucial in providing patient-centered care.

Effectiveness of Perineural Injections Combined with Standard Postoperative Total Knee Arthroplasty Protocols in the Management of Chronic Postsurgical Pain After Total Knee Arthroplasty

Background

Despite increased experience and technical developments in total knee arthroplasty (TKA), chronic postsurgical pain (CPSP) remains one of physicians’ biggest challenges. The aim of the present study was to evaluate the effectiveness of perineural injection therapy (PIT) in the management of CPSP after TKA.

Material/Methods

A total of 60 patients who had been surgically treated with TKA because of advanced knee osteoarthritis was included in the present study. The study included 2 groups. Group A consisted of patients who received 3 rounds of PIT combined with standard postoperative TKA protocol during the same period. Group B received standard postoperative TKA protocols (rehabilitation programs, oral and intravenous analgesics). Clinical effectiveness was evaluated via Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Visual Analog Scale (VAS) at baseline and 1-, 3-, and 6-month follow-ups.

Results

All repeated measures showed significant improvements (P<0.001) in both groups for VAS and WOMAC scores. These scores were significantly better in group A in all follow-up periods compared with group B (P<0.001). Twenty-nine patients (93.5%) in group A reported excellent or good outcomes compared with 26 patients (89.6%) in group B.

Conclusions

PIT is a promising approach in CPSP with minimal cost, simple and secure injection procedures, minimal side effects, and higher clinical efficacy.

A novel behavioural INTErvention to REduce Sitting Time in older adults undergoing orthopaedic surgery (INTEREST): results of a randomised-controlled feasibility study

BACKGROUND

Osteoarthritis is a prevalent condition in older adults that causes many patients to require a hip or knee replacement. Reducing patients' sedentariness prior to surgery may improve physical function and post-operative outcomes.

METHODS

We conducted a pragmatic randomised-controlled feasibility study with 2:1 allocation into intervention or usual care groups. The intervention, based on Self-Determination Theory, involved techniques to reduce sedentary behaviour, including motivational interviewing, setting of behavioural goals, and more. The primary outcome was feasibility, assessed using mixed methods. We included exploratory measures to inform a future definitive trial, such as ActivPal3 accelerometry to measure movement, the Short Physical Performance Battery (SPPB), Basic Psychological Needs, and cardiometabolic biomarkers. Assessments were at baseline, 1-week pre-surgery, and 6-week post-surgery.

RESULTS

We recruited 35 participants aged ≥ 60 years approximately 8 weeks before hip or knee arthroplasty. Participant uptake rate was 14.2%, and retention rate 85.7%. Participants were very satisfied with the study which was found to be feasible with some modifications. Exploratory within-group comparisons found that the intervention has potential to improve SPPB by 0.71 points from baseline to pre-surgery, a clinically significant increase, and reduce sedentary time by up to 66 min d-1.

CONCLUSION

In this older surgical population, it is feasible to use behavioural techniques to displace sedentary time to activity and to conduct a trial spanning the period of surgical intervention. This may improve physical function and surgical outcomes. The INTEREST intervention is now ready for evaluation in a full-scale randomised-controlled trial.

REGISTRATION

This trial was registered on Clinicaltrials.gov on 13/11/2018. ID: NCT03740412.

Complications to 6 months following total hip or knee arthroplasty: observations from an Australian clinical outcomes registry

Background

Total hip and total knee arthroplasty (THA/TKA) are increasing in incidence annually. While these procedures are effective in improving pain and function, there is a risk of complications.

Methods

Using data from an arthroplasty registry, we described complication rates including reasons for reoperation and readmission from the acute period to six months following THA and TKA in an Australian context. Data collection at 6 months was conducted via telephone interview, and included patient-reported complications such as joint stiffness, swelling and paraesthesia. We used logistic regression to identify risk factors for complications.

Results

In the 8444 procedures included for analysis, major complications were reported by 9.5 and 14.4% of THA and TKA patients, respectively, whilst minor complications were reported by 34.0 and 46.6% of THA and TKA patients, respectively. Overall complications rates were 39.7 and 53.6% for THA and TKA patients, respectively. In THA patients, factors associated with increased risk for complications included increased BMI, previous THA and bilateral surgery, whereas in TKA patient factors were heart disease, neurological disease, and pre-operative back pain and arthritis in a separate joint. Female gender and previous TKA were identified as protective factors for minor complications in TKA patients.

Conclusion

We found moderate rates of major and high rates of minor postoperative complications following THA and TKA in Australia and have identified several patient factors associated with these complications. Efforts should be focused on identifying patients with higher risk and optimising pre- and post-operative care to reduce the rates of these complications.

Five years' trajectories of functionality and pain in patients after hip or knee replacement and association with long-term patient survival

To describe the 5 years’ trajectories in functionality and pain of patients with hip or knee osteoarthritis and arthroplasty and analyze the association of these with long-term patients survival. Patients with OA receiving total hip or knee arthroplasty were recruited and completed two sets of standardized questionnaires for functionality and pain 6, 12, and 60 months postoperatively. Multivariate mixed models were conducted to assess trajectories over time and the resulting improvement per month during the last time period was included in a landmark-model to estimate adjusted hazard ratios for mortality. In total 809 patients with joint replacement were included (mean age 65.0 years, 62.2% female), 407 patients died (median follow-up 18.4 years). Both instruments of functionality and pain showed extensive improvement during the first 6 months. Baseline and change in functionality (both p < 0.001) and pain (p = 0.02) during the first 6 months were associated with mortality. Better values in functionality corresponded with improved survival whereas the association with the pain scores was inverse. In patients with hip and knee OA, an explicit improvement in function is seen within the first 6 months after arthroplasty. In addition, especially the functionality scores at baseline as well as their improvement showed an association with long-term patient survival.