Supervised machine learning for the prediction of post-operative clinical outcomes of hip and knee replacements: a review

Prediction models are being increasingly used in the medical field to identify risk factors and possible outcomes. Some of these are presently being used to develop guidelines for improving clinical practice. The application of machine learning (ML), comprising a powerful set of computational tools for analysing data, has been clearly expanding in the role of predictive modelling. This paper reviews the latest developments of supervised ML techniques that have been used to analyse data related to post-operative total hip and knee replacements. The aim was to review the most recent findings of relevant published studies by outlining the methodologies employed (most-widely used supervised ML techniques), data sources, domains, limitations of predictive analytics and the quality of predictions.

Deep Learning-based Thigh Muscle Investigation Using MRI For Prosthetic Development for Patients Undergoing Total Knee Replacement (TKR)

BACKGROUND

A prosthetic device is designed based on the quantitative analysis of muscle MRI which will improve the muscle control achieved with functional electrical stimulation/ guided robotic exoskeletons. Electromyography (EMG) provides muscle functionality information while MRI provides the physiological and functionality of muscles. The sensor feedbacks were used for the bionic prosthesis, but the length of muscle using image processing was not correlated.

OBJECTIVE

To investigate and perform qualitative and quantitative assessment of thigh muscle using MRI. The objective of the work is to improve the existing VAG signal classification method to diagnose abnormality using MRI for patients undergoing Total knee replacement (TKR).

METHODS

A deep learning method for qualitative and quantitative assessment of thigh muscle is done using MRI. In existing prosthetic devices, electrical measurements of a person's muscles are obtained using surface or implantable electrodes. Several methods were used for the classification and diagnostic processes. The existing methods have drawbacks in feature extraction and require experts to design the system. This work combines medical image processing and orthopaedic prosthetics to develop a therapeutic method.

RESULTS & DISCUSSION

This design provides much more precise control of prosthetic limbs using the image processing technique. The hybrid CNN swarm-based method measures the muscle structure and functions. Along with the sensor readings, these details are combined for prosthetic control. The implementation was carried out in MATLAB, Sketchuppro, and Arduino IDE.

CONCLUSION

A combined swarm intelligence and deep learning method were proposed for qualitative and quantitative assessment of thigh muscle. The prosthetic device choice was done from the scanned MRI image like Humerus-T prosthetics, segmental prosthesis and arthrodesis prosthesis. The investigation was done for the Total knee replacement (TKR) approach.

Significantly better precision with new machine learning versus manual image registration software in processing images from single-plane fluoroscopy to determine tibiofemoral kinematics following total knee replacement

One common method to determine tibiofemoral kinematics following total knee replacement (TKR) is to capture single-plane fluoroscopic images of a patient activity and determine anterior-posterior (AP) positions of the femoral condyles and internal-external (IE) tibial rotation. Although JointTrack is widely used to analyze such images, precision (i.e. repeatability) in determining AP positions and IE tibial rotations using the two publicly available programs has never been quantified. The objectives were to determine the precision and reproducibility of results using both programs. Fluoroscopic images of 16 patients who performed a weight-bearing deep knee bend following TKR were analyzed. JointTrack Manual (JTM) and JointTrack Machine Learning (JTML) were used to perform 3D model-to-2D image registration after which AP positions of the femoral condyles and IE tibial rotations were determined. Precision in AP positions and IE rotations was quantified. Intraclass correlation coefficients (ICCs) for both repeatability (i.e. intraobserver) and reproducibility (i.e. interobserver) also were determined. Precision using JTM was worse than JTML for AP positions of the medial and lateral femoral condyles (1.0 mm and 0.9 mm vs 0.3 mm and 0.4 mm, respectively; p < 0.001 for both). For IE tibial rotation, precision also was worse using JTM versus JTML (1.1º vs 0.9°, p = 0.010). ICC values for JTML indicated good to excellent agreement (range: 0.82-0.98) whereas ICC values for JTM indicated only moderate to good agreement (range: 0.58-0.88). JTML has better precision and reproducibility than JTM and also is more efficient to use. Therefore, use of JTML over JTM is strongly recommended.

Modified Frailty Index as a Predictor of Adverse Outcomes in Elective Primary Hip and Knee Replacement Surgery Patients at a Tertiary Care Hospital in Pakistan: A Cross-Sectional Study

Objective The objective was to evaluate the modified frailty index as a predictor of early (within 30 days) postoperative complications in total joint arthroplasty patients, in a low middle-income country. Material and methods A cross-sectional study was carried out which included patients with ages ranging from 23 to 86 years, who underwent elective primary Total Hip or Knee Arthroplasties (TKA or THA) between December 2021 and February 2023. Modified frailty index (mFI-5) was calculated and 30-day morbidity and mortality were recorded. Post-operative complications were categorized as either surgical or medical and recorded. Results A total of 175 patients were included, amongst whom the majority were females (68.6%, n=120) and the mean age was 60.5 ± 13.2 years. 85 patients (48.6%) had a mFI-5 score of one while 48 patients (27.4%) had a score of two. Superficial surgical site infection was the most common complication overall in 6 patients (3.4%); however, no case of prosthetic joint infection was noted. Deep vein thrombosis (DVT) was the most common medical complication (1.7%, n=3). 5 patients (2.9%) required re-admission and two mortalities were recorded within the 30-day interval. A significant association was noted between post-operative surgical complications and mFI-5 score (p-value = < 0.001), with the risk of complications increasing with a higher mFI-5 score. Smoking was noted to be a risk factor for post-operative medical complications as well as 30-day mortality. Conclusion The current study shows that the mFI-5 index can effectively be used as a predictor of postoperative complications in the South Asian region such as Pakistan. This should be calculated routinely and can be used as a tool for pre-operative assessment and counseling.

Use of patellofemoral digital twins for patellar tracking and treatment prediction: comparison of 3D models and contact detection algorithms

Introduction: Poor patellar tracking can result in painful contact pressures, patella subluxation, or dislocation. The use of musculoskeletal models and simulations in orthopedic surgeries allows for objective predictions of post-treatment function, empowering clinicians to explore diverse treatment options for patients. Although a promising approach for managing knee surgeries, the high computational cost of the Finite Element Method hampers its clinical usability. In anticipation of minimal elastic deformations in the involved bodies, the exploration of the Multibody Dynamics approach emerged as a viable solution, providing a computationally efficient methodology to address clinical concerns related to the knee joint. Methods: This work, with a focus on high-performance computing, achieved the simulation of the patellofemoral joint through rigid-body multibody dynamics formulations. A comparison was made between two collision detection algorithms employed in the simulation of contact between the patellar and femoral implants: a generic mesh-to-mesh collision detection algorithm, which identifies potential collisions between bodies by checking for proximity or overlap between their discretized mesh surface elements, and an analytical contact algorithm, which uses a mathematical model to provide closed-form solutions for specific contact problems, but cannot handle arbitrary geometries. In addition, different digital twins (3D model geometries) of the femoral implant were compared. Results: Computational efficiency was considered, and histories of position, orientation, and contact force of the patella during the motion were compared with experimental measurements obtained from a sensorized 3D-printed test bench under pathological and treatment scenarios. The best results were achieved through a purely analytical contact detection algorithm, allowing for clinical usability and optimization of clinical outcomes.

Near-Infrared Dual-Modal Sensing of Force and Temperature in Total Knee Replacement Using Mechanoluminescent Phosphor of Sr3 Sn2 O7 : Nd, Yb

Knee replacement surgery confronts challenges including patient dissatisfaction and the necessity for secondary procedures. A key requirement lies in dual-modal measurement of force and temperature of artificial joints during postoperative monitoring. Here, a novel non-toxic near-infrared (NIR) phosphor Sr3 Sn2 O7 :Nd, Yb, is designed to realize the dual-modal measurement. The strategy is to entail phonon-assisted upconversion luminescence (UCL) and trap-controlled mechanoluminescence (ML) in a single phosphor well within the NIR biological transmission window. The phosphor is embedded in medical bone cement forming a smart joint in total knee replacements illustrated as a proof-of-concept. The sensing device can be charged in vitro by a commercial X-ray source with a safe dose rate for ML, and excited by a low power 980 nm laser for UCL. It attains impressive force and temperature sensing capabilities, exhibiting a force resolution of 0.5% per 10 N, force detection threshold of 15 N, and a relative temperature sensitive of up to 1.3% K-1 at 309 K. The stability against humidity and thermal shock together with the robustness of the device are attested. This work introduces a novel methodological paradigm, paving the way for innovative research to enhance the functionality of artificial tissues and joints in living organisms.

Effects of kinesiotaping during early post-operative rehabilitation in individuals who underwent a total knee arthroplasty: A systematic review and meta-analysis of randomized control trials

OBJECTIVE

To report the treatment effects of early use kinesiotaping on pain, range of motion, mobility, and edema outcomes following total knee arthroplasty.

DATA SOURCES

Cochrane Central Register of Controlled Trials, PubMED, SPORTDiscus, Biosis Citation Index, and the Cumulative Index to Nursing and Allied Health Literature were searched for potential randomized control trials from inception to 8 January 2024.

REVIEW METHODS

Randomized control trials evaluating the effect of kinesiotaping published in English were included. Reference lists for relevant reviews were searched. Study quality was assessed using the Cochrane Risk of Bias 2 tool. Certainty of evidence was determined using the Grading of Recommendations Assessment, Development, and Evaluation approach.

RESULTS

Seven articles totaling 534 participants were included for meta-analysis. Kinesiotaping with standard rehabilitation when compared to standard rehabilitation alone had very low certainty of evidence in pain and knee flexion range of motion. Kinesiotaping was favored at post-operative days two to four for pain (P = 0.03, standard mean difference = -0.77 [-1.45, -0.09]) and range of motion (P = 0.002, standard mean difference = -0.24 [-0.44, -0.03]). Kinesiotaping was favored at post-operative days six to eight for pain (P = 0.02, standard mean difference = -0.76 [-1.41, -0.12]) and range of motion (P = 0.04, standard mean difference = -0.63 [-1.22, -0.04]). Edema and mobility could not be meta-analyzed.

CONCLUSION

The use of kinesiotaping early in post-operative rehabilitation could be a useful modality for reducing pain and increasing the range of knee flexion, however, the certainty of evidence is very low.

Social risk and patient-reported outcomes after total knee replacement: Implications for Medicare policy

OBJECTIVE

To determine whether county-level or patient-level social risk factors are associated with patient-reported outcomes after total knee replacement when added to the comprehensive joint replacement risk-adjustment model.

DATA SOURCES AND STUDY SETTING

Patient and outcomes data from the Function and Outcomes Research for Comparative Effectiveness in Total Joint Replacement cohort were merged with the Social Vulnerability Index from the Centers for Disease Control and Prevention.

STUDY DESIGN

This prospective longitudinal cohort measured the change in patient-reported pain and physical function from baseline to 12 months after surgery. The cohort included a nationally diverse sample of adult patients who received elective unilateral knee replacement between 2012 and 2015.

DATA COLLECTION/EXTRACTION METHODS

Using a national network of over 230 surgeons in 28 states, the cohort study enrolled patients from diverse settings and collected one-year outcomes after the surgery. Patients <65 years of age or who did not report outcomes were excluded.

PRINCIPAL FINDINGS

After adjusting for clinical and demographic factors, we found patient-reported race, education, and income were associated with patient-reported pain or functional scores. Pain improvement was negatively associated with Black race (CI = -8.71, -3.02) and positively associated with higher annual incomes (≥$45,00) (CI = 0.07, 2.33). Functional improvement was also negatively associated with Black race (CI = -5.81, -0.35). Patients with higher educational attainment (CI = -2.35, -0.06) reported significantly less functional improvement while patients in households with three adults reported greater improvement (CI = 0.11, 4.57). We did not observe any associations between county-level social vulnerability and change in pain or function.

CONCLUSIONS

We found patient-level social factors were associated with patient-reported outcomes after total knee replacement, but county-level social vulnerability was not. Our findings suggest patient-level social factors warrant further investigation to promote health equity in patient-reported outcomes after total knee replacement.

Individual Factors Modifying Postoperative Pain Management in Elective Total Hip and Total Knee Replacement Surgery

Total hip and knee replacements are the most common orthopedic procedures performed due to osteoarthritis. Pain is an intrinsic symptom accompanying osteoarthritis, persisting long before surgery, and continuing during the preoperative and postoperative periods. Appropriate pain management after surgery determines the comfort, duration, and cost of hospitalization, as well as the effectiveness of postoperative rehabilitation. Individual differences in pain perception and tolerance in orthopedic patients remain an important research topic. Therefore, the aim of this study was to investigate the predictors of analgesic requirements (morphine, acetaminophen, and ketoprofen), including individual pain threshold and tolerance, body mass index (BMI), diabetes, and beliefs about pain control in patients undergoing elective hip or knee arthroplasty using a multilevel regression model (N = 147, 85 women, 62 men, 107 after hip replacement, and 40 after knee replacement). Results: Higher pain tolerance was associated with a lower dose of morphine per kg after surgery. Patients undergoing hip surgery received a lower dose of ketoprofen than patients undergoing knee surgery. The more the patient believed in personal pain control, the stronger the negative relationship between pain tolerance and morphine requirement. The lowest doses were given to patients with the highest pain tolerance and the greatest belief in personal control. Factors such as belief in pain control and pain tolerance should be considered in comprehensive postoperative pain management in orthopedic patients to reduce opioid doses and, thus, side effects.

Listeria innocua infection in an old case of total knee replacement - an unusual case report

Prosthetic implant-associated arthritis due to Listeria is mostly reported for Listeria monocytogenes. Here, we describe a patient who underwent total knee replacement 12 years ago and presented with pain, tenderness, redness and local rise in temperature in the right knee. Purulent fluid was aspirated. Upon microbiological analysis, culture yielded Listeria innocua. L. innocua is rare. Listeria is not reported as a contaminant and routine cultures may be negative. Because of the long interval between surgery and the onset of symptoms, clinical suspicion, radiological investigations and analysing multiple samples are of immense help.

Exploring the Performance of an Artificial Intelligence-Based Load Sensor for Total Knee Replacements

Using tibial sensors in total knee replacements (TKRs) can enhance patient outcomes and reduce early revision surgeries, benefitting hospitals, the National Health Services (NHS), stakeholders, biomedical companies, surgeons, and patients. Having a sensor that is accurate, precise (over the whole surface), and includes a wide range of loads is important to the success of joint force tracking. This research aims to investigate the accuracy of a novel intraoperative load sensor for use in TKRs. This research used a self-developed load sensor and artificial intelligence (AI). The sensor is compatible with Zimmer's Persona Knee System and adaptable to other knee systems. Accuracy and precision were assessed, comparing medial/lateral compartments inside/outside the sensing area and below/within the training load range. Five points were tested on both sides (medial and lateral), inside and outside of the sensing region, and with a range of loads. The average accuracy of the sensor was 83.41% and 84.63% for the load and location predictions, respectively. The highest accuracy, 99.20%, was recorded from inside the sensing area within the training load values, suggesting that expanding the training load range could enhance overall accuracy. The main outcomes were that (1) the load and location predictions were similar in accuracy and precision (p > 0.05) in both compartments, (2) the accuracy and precision of both predictions inside versus outside of the triangular sensing area were comparable (p > 0.05), and (3) there was a significant difference in the accuracy of load and location predictions (p < 0.05) when the load applied was below the training loading range. The intraoperative load sensor demonstrated good accuracy and precision over the whole surface and over a wide range of load values. Minor improvements to the software could greatly improve the results of the sensor. Having a reliable and robust sensor could greatly improve advancements in all joint surgeries.

Differences in Trochlear Morphology of a New Femoral Component Designed for Kinematic Alignment from a Mechanical Alignment Design

Because kinematic alignment (KA) aligns femoral components in greater valgus and with less external rotation than mechanical alignment (MA), the trochlear groove of an MA design used in KA is medialized, which can lead to complications. Hence, a KA design has emerged. In this study, our primary objective was to quantify differences in trochlear morphology between the KA design and the MA design from which the KA design evolved. The KA and MA designs were aligned in KA on ten 3D femur-cartilage models. Dependent variables describing the morphology of the trochlea along the anterior flange, which extends proximal to the native trochlea, and along the arc length of the native trochlea, were determined, as was flange coverage. Along the anterior flange, the KA groove was significantly lateral proximally by 10 mm and was significantly wider proximally by 5 mm compared to the MA design (p < 0.0001). Along the arc length of the native trochlea, the KA groove was significantly lateral to the MA design by 4.3 mm proximally (p ≤ 0.0001) and was significantly wider proximally by 19 mm than the MA design. The KA design reduced lateral under-coverage of the flange from 4 mm to 2 mm (p < 0.0001). The KA design potentially mitigates risk of patellofemoral complications by lateralizing and widening the groove to avoid medializing the patella for wide variations in the lateral distal femoral angle, and by widening the flange laterally to reduce under-coverage. This information enables clinicians to make informed decisions regarding use of the KA design.

Functional Outcome of Subvastus versus Medial Parapatellar Approaches for Total Knee Replacement in Patients with Knee Osteoarthritis: A Prospective Cohort Study

Background

Subvastus approach and medial parapatellar approach are two major approaches for total knee replacement (TKR). There is no global consensus on the superiority of either approach in terms of functional outcomes.

Objective

The present study aimed to evaluate the functional outcome of TKR through subvastus approach and medial parapatellar approach by using patient-reported scores at 3-, 6-, and 12-month post-operative follow-ups.

Methods

This prospective cohort follow-up study included patients with knee osteoarthritis who underwent elective primary TKR either through the subvastus or medial parapatellar approaches at King Abdullah Medical City, Makkah city, Kingdom of Saudi Arabia, from January 2019 to December 2022. Scores from the self-reported Oxford Knee Score (OKS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were compared in the two groups of patients at 3-, 6-, and 12-month post-operative follow-ups.

Results

A total of 98 patients were included, of which 37 underwent TKR through the subvastus approach and 61 through the medial parapatellar approach. There was an overall significant change over time in both WOMAC and OKS scores (P < 0.001). Patients who underwent the subvastus approach had significantly higher mean of WOMAC and OKS than patients with the medial parapatellar approach at the 3- and 6-month follow-ups (P < 0.05), but not at the 12-month follow-up.

Conclusions

For TKR, the medial parapatellar approach results in better functional outcomes at the 3- and 6- month follow-up periods compared with the subvastus approach.

Total Knee Replacement in a Young Patient with Valgus Knee Osteoarthritis: A Case Report

Introduction

Valgus deformity is characterized by an outward angulation of the knee joint. The most common cause of valgus deformity is osteoarthritis (OA), a prevalent progressive joint disease that causes chronic pain and functional limitations. Total knee replacement (TKR) is rarely done in patients with grade-I valgus deformity and young age. To the best of our knowledge, this is the first case report of its kind.

Case Report

A 34-year-old man presented to us with 15 years of persistent, progressively worsening right knee pain that was interfering with his daily activities. No non-operative treatment could alleviate his severe pain. Physical examination revealed a positive valgus stress test, limited knee extension, and an asymmetrical gait. He was diagnosed with a grade-I valgus deformity of the right osteoarthritic knee. History, physical examination, and radiological findings confirmed the diagnosis. In consideration of severe pain and impaired quality of life, we opted to perform TKR using a medial parapatellar approach. Regular follow-ups were done after the procedure. He experienced no pain or recurrence of deformity. He was very satisfied with the result. His Western Ontario and McMaster Universities OA Index score at 12 months following surgery was 5, indicating a favorable outcome.

Conclusion

This case exhibits the effectiveness of TKR in treating grade-I valgus deformity of the osteoarthritic knee with severe pain in a young adult, resulting in improved pain alleviation, mobility, joint alignment, and overall quality of life.

Efficacy of Intraoperative Periarticular Local Infiltration for Pain Control and Ambulation in Total Knee Arthroplasty: A Randomized Case-Control Study

INTRODUCTION

Total knee arthroplasty (TKA) is a leading operative procedure for late-stage knee osteoarthritis. The cornerstone of a successful TKA is swift and effective rehabilitation to achieve a pain-free and good range of motion. Pain post-replacement hinders an effective rehabilitation protocol. Reported preoperative, perioperative, and postoperative analgesia modes have undesirable side effects. The purpose of this study is to assess the effect of a unique cocktail injection on immediate postoperative pain using the visual analog score, the need for additional analgesics during the initial period, and the ambulation time between the case and control groups.

MATERIALS AND METHODS

In this randomized case-control study, the periarticular injection consisted of ropivacaine 0.75 mg/ml (28 ml), epinephrine 1 mg/ml (0.5 ml), and ketorolac 30 mg/ml (1 ml) added to 50 ml of normal saline to make 80 ml of solution. Fifty patients were chosen and randomly divided into two groups of 25 each by computer-generated randomization. The case group received the cocktail injection, and the control group was injected locally with normal saline. Visual analog scale (VAS) was assessed at 3, 6, 12, and 24 hr post-surgery, and the amount of additional analgesics used and ambulation time were assessed.

RESULTS

A total of 50 patients who underwent TKA were selected and divided into case and control groups of 25 each. The majority of the patients had osteoarthritis, and a few had rheumatoid arthritis. No significant differences in demographic data (age, gender, body-mass index) or surgical time. The case group had excellent VAS scores between 0 and 3 at 3, 6, 12, and 24 hr (p < .001). The amount of additional analgesia required in the case group was minimal (<3 doses) in 96% of the patients on Day 1. More than 80% of patients could ambulate pain-free on Day 1.

CONCLUSION

Pain reduction with early ambulation was noted in a significant number of individuals with the use of this unique intraoperative local cocktail injection. This pain-free initial period following TKA prepared patients for an effective rehabilitation program.

Association Between Patient and Facility Characteristics and Rehabilitation Outcomes After Joint Replacement Surgery in Different Rehabilitation Settings for Older Adults: A Systematic Review

BACKGROUND AND PURPOSE

In the United States, an exponential increase in total hip arthroplasty (THA) and total knee arthroplasty (TKA) demand has occurred over the last 2 decades. Evidence suggesting patients receiving inpatient rehabilitation following a TKA or THA experience similar outcomes as those with rehabilitation in other settings led to dramatic shifts in postsurgical care settings owing to Centers for Medicare & Medicaid Services (CMS) payment reforms. A contemporary synthesis of evidence about the association between patient and facility factors and outcomes from older adults undergoing THA or TKA in the United States is needed.

METHODS

To identify eligible studies, we searched PubMed, Scopus, and CINAHL. We followed PRISMA guidelines to identify articles evaluating either patient or facility factors associated with outcomes after THA or TKA for older adults who may have been cared for in inpatient settings (ie, inpatient rehabilitation or skilled nursing facility [SNF]). Eligible articles were conducted in the United States and were published between January 1, 2000, and December 31, 2021.

RESULTS

We included 8 articles focused on patient factors and 9 focused on facility factors. Most included older adults and the majority were White (in those reporting race/ethnicity). Most studies evaluated outcomes at discharge and showed that patients admitted to inpatient rehabilitation facilities had either similar or better functional outcomes (mobility, self-care, and functional independence measure (FIM) score) and lower length of stay compared with those in SNFs. Few studies focused on home health care.

CONCLUSIONS

The systematic review focused on older adults showed that findings in these patients are consistent with previous research. Older adults undergoing THA/TKA had acceptable outcomes regardless of postsurgical, inpatient setting of care. Research conducted after CMS payment reforms, in home health care settings, and in more diverse samples is needed. Given the known racial/ethnic disparities in THA/TKA and the shifts to postsurgical home health care with little regulatory oversight of care quality, contemporary research on outcomes of postsurgical THA/TKA outcomes is warranted.

A Prospective Randomized Study on Whether Computer Navigation Is Better Than Conventional Total Knee Replacement in Terms of Short-Term Functional and Clinical Outcomes

INTRODUCTION

 Computer navigation results in better radiological alignment in total knee replacement (TKR). However, functional and clinical outcomes are equally good in conventional TKR. This study aims to compare the functional and clinical outcomes in patients undergoing navigated and conventional TKR.

METHODS

A prospective randomized study between navigated TKR (NKR/Group I) and conventional TKR (CKR/Group II) was carried out. Functional outcome was analyzed using the Oxford Knee Score (OKS) and Western Ontario and McMaster Universities Arthritis Index (WOMAC) score. Clinical outcome was evaluated as knee range of motion.

RESULTS

Thirty-nine patients (68 knees) were randomized into two groups: I and II. The mean follow-up was 26 months. There was no statistically significant difference between the two groups with respect to knee range of motion, OKS, and WOMAC score at the final follow-up.

CONCLUSION

We concluded that there is no difference in clinical and functional outcomes between navigated and conventional TKR.

Does a consumer co-designed infographic increase knowledge of physical activity after total knee joint replacement? A randomised controlled trial

PURPOSE

To determine if a consumer co-designed infographic increased knowledge of physical activity and self-efficacy for exercise after total knee joint replacement surgery.

METHODS

Forty-four adults with primary knee joint replacement surgery were recruited from a public and a private hospital in Melbourne, Australia. Participants were randomly allocated to an experimental or control group. The experimental group received a consumer co-designed infographic. All participants received usual care. Primary outcome measures were knowledge of physical activity and self-efficacy for exercise. Outcomes were administered at baseline, week 1 and week 6. Semi-structured interviews with experimental group participants explored the acceptability, implementation and efficacy of the infographic.

RESULTS

There were no between-group differences for knowledge of physical activity at week 1 (MD -0.02 units, 95% CI -0.9 to 0.9) or week 6 (MD 0.01 units, 95% CI -0.9 to 0.9). Self-efficacy for exercise increased at week 1 (MD 14.2 units, 95% CI 2.9-25.4) but was not sustained. Qualitative data showed that the infographic was embraced by some participants but not by others.

CONCLUSIONS

A consumer co-designed infographic did not improve knowledge of physical activity but may have had a short-term positive effect on self-efficacy for exercise after knee joint replacement. Trial registration ACTRN12621000910808.

Supporting patients to prepare for total knee replacement: Evidence-, theory- and person-based development of a 'Virtual Knee School' digital intervention

INTRODUCTION

Digital delivery of pre-operative total knee replacement (TKR) education and prehabilitation could improve patient outcomes pre- and post-operatively. Rigorously developing digital interventions is vital to help ensure they achieve their intended outcomes whilst mitigating their potential drawbacks.

OBJECTIVE

To develop a pre-operative TKR education and prehabilitation digital intervention, the 'Virtual Knee School' (VKS).

METHODS

The VKS was developed using an evidence-, theory- and person-based approach. This involved a mixed methods design with four phases. The first three focused on planning the VKS. The final phase involved creating a VKS prototype and iteratively refining it through concurrent think-aloud interviews with nine patients who were awaiting/had undergone TKR. Meta-inferences were generated by integrating findings from all the phases. ISRCTN registration of the overall project was obtained on 24 April 2020 (ISRCTN11759773).

RESULTS

Most participants found the VKS prototype acceptable overall and considered it a valuable resource. Conversely, a minority of participants felt the prototype's digital format or content did not meet their individual needs. Participants' feedback was used to refine the prototype's information architecture, design and content. Two meta-inferences were generated and recommend: 1. Comprehensive pre-operative TKR education and prehabilitation support should be rapidly accessible in digital and non-digital formats. 2. Pre-operative TKR digital interventions should employ computer- and self-tailoring to account for patients' individual needs and preferences.

CONCLUSIONS

Integrating evidence, theory and stakeholders' perspectives enabled the development of a promising VKS digital intervention for patients awaiting TKR. The findings suggest future research evaluating the VKS is warranted and provide recommendations for optimising pre-operative TKR care.

PATIENT OR PUBLIC CONTRIBUTION

Patient and Public Involvement (PPI) was central throughout the project. For example, PPI representatives contributed to the project planning, were valued members of the Project Advisory Group, had key roles in developing the VKS prototype and helped disseminate the project findings.

Effect of Low-Level Laser Therapy on Knee Range of Motion and Functional Abilities After Total Knee Arthroplasty

OBJECTIVE

The aim of this study was to determine the effectiveness of combined low-level laser therapy (LLL) and rehabilitation in patients following recent total knee replacement (TKR).

METHODS

A double-blind randomized controlled study was conducted at the Orthopedic Department of Mansoura University Hospital. Forty-four patients were chosen from a total of 58 patients who met the inclusion criteria and were assigned randomly into control and experimental groups of equal size. Ultimately, 40 patients completed the study (20 from each group). Both groups participated in an intensive functional rehabilitation program, and the experimental group also received LLL therapy around the knee at the incisional line, the medial and lateral intra-articular space, above and below the patella, and at the popliteal fossa at low fluence (6 J/cm2, 650 nm continuous wave) and 60 s per point with a total dose of 48 J per session over 12 treatment sessions for six weeks. Knee range of motion (ROM) was measured with a digital goniometer, and functional abilities were assessed with the Arabic version of the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index.

RESULTS

There were significant differences in all variables pre- and post-treatment within each group. Before treatment, there was no significant difference in any of the measured variables between the groups (P>0.05). After treatment, there were significant differences in knee flexion ROM and WOMAC index (P<0.05) but no significant difference in knee extension ROM between the groups (P>0.05).

CONCLUSION

The addition of low-level laser therapy to a rehabilitation program post-TKR resulted in substantial enhancements in knee flexion range of motion and the WOMAC index.

Validation of the Finite Element Model versus Biomechanical Assessments of Dental Implants and Total Knee Replacements

Computer modeling and simulation (CM&S) technology is widely used in the medical device industry due to its advantages such as reducing testing time and costs. However, the developer's parameter settings during the modeling and simulation process can have a significant impact on the results. This study developed a test model for the rotational shear strength of dental implants and the constraint force of total knee replacements based on CM&S technology and proposes ideal parameters to ensure reliability. For dental implants, the load area and sliding contact conditions were considered, and for total knee replacements, the friction coefficient, medial-lateral displacement, valgus-varus rotation, and elastic modulus were considered. By comparing the simulation results and mechanical tests, boundary conditions with an error rate of less than 1.5% were selected. When a jig (gripper and collector) was applied with the same boundary conditions, an error rate of 48~22% occurred; otherwise, it was confirmed that the error rate was within 10~0.2%. The FE model was verified with an error of 2.49 to 3% compared to the mechanical test. The friction coefficient variable had the greatest influence on the results, accounting for 10 to 13%, and it was confirmed that valgus-varus rotation had a greater influence on the results than medial-lateral displacement. Relatively, the elastic modulus of the insert had the least effect on the results. These research results are expected to make CM&S techniques useful as a medical device digital development tool (M3DT) in the development of total knee replacements and dental implants.

The incidence and risk factors for abnormal postoperative blood tests following primary total joint replacement

Aims

We aim to evaluate the usefulness of postoperative blood tests by investigating the incidence of abnormal results following total joint replacement (TJR), as well as identifying preoperative risk factors for abnormal blood test results postoperatively, especially pertaining to anaemia and acute kidney injury (AKI).

Methods

This is a retrospective cohort study of patients who had elective TJR between January and December 2019 at a tertiary centre. Data gathered included age at time of surgery, sex, BMI, American Society of Anesthesiologists (ASA) grade, preoperative and postoperative laboratory test results, haemoglobin (Hgb), white blood count (WBC), haematocrit (Hct), platelets (Plts), sodium (Na+), potassium (K+), creatinine (Cr), estimated glomerular filtration rate (eGFR), and Ferritin (ug/l). Abnormal blood tests, AKI, electrolyte imbalance, anaemia, transfusion, reoperation, and readmission within one year were reported.

Results

The study included 2,721 patients with a mean age of 69 years, of whom 1,266 (46.6%) were male. Abnormal postoperative bloods were identified in 444 (16.3%) patients. We identified age (≥ 65 years), female sex, and ASA grade ≥ III as risk factors for developing abnormal postoperative blood tests. Preoperative haemoglobin (≤ 127 g/dl) and packed cell volume (≤ 0.395 l/l) were noted to be significant risk factors for postoperative anaemia, and potassium (≤ 3.7 mmol/l) was noted to be a significant risk factor for AKI.

Conclusion

The costs outweigh the benefits of ordering routine postoperative blood tests in TJR patients. Clinicians should risk-stratify their patients and have a lower threshold for ordering blood tests in patients with abnormal preoperative haemoglobin (≤ 127 g/l), blood loss > 300 ml, chronic kidney disease, ASA grade ≥ III, and clinical concern.

Proximal versus distal adductor canal catheters for total knee arthroplasty: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

Total knee arthroplasty (TKA) is associated with severe postoperative pain. Continuous adductor canal blockade provides analgesia while preserving quadriceps muscle strength. Nevertheless, uncertainty still exists as to the optimal adductor canal catheter placement approach. We sought to conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing the analgesic effects of proximal vs distal adductor canal catheters in patients undergoing TKA.

SOURCE

We systematically searched PubMed, EMBASE, and Cochrane for RCTs comparing distal and proximal adductor canal catheters for TKA regarding critical clinical outcomes in adult patients. Statistical analysis was performed using R version 4.1.2 (R Foundation for Statistical Computing, Vienna, Austria). Heterogeneity was assessed using the Cochran Q test and I2 statistics. Trial sequential analysis (TSA) was performed to evaluate the risk of random errors and the uncertainty of our results. The risk of bias was appraised according to the RoB-2 tool.

PRINCIPAL FINDINGS

Six RCTs and 352 patients were included, of whom 151 (42.9%) were male, and 175 (49.7%) were randomized to undergo proximal adductor canal catheter placement. Due to the randomized nature of the studies, baseline characteristics were similar between groups. There were no statistical differences between proximal and distal adductor canal catheters regarding cumulative opioid consumption in the first 24 hr (mean difference [MD], -4.86; 95% confidence interval [CI], -15.19 to 5.47; P = 0.36; four RCTs; 240 patients); pain scores at rest (MD, 0.41; 95% CI, -1.23 to 0.40; P = 0.32; six RCTs; 350 patients); and pain scores with movement for the first 24 hr (MD, -0.25; 95% CI, -0.85 to 0.35; P = 0.42; four RCTs; 246 patients). In the TSA, the required information size was not reached, and the Z-curve did not cross the monitoring boundaries in any of the endpoints.

CONCLUSION

These findings suggest that proximal vs distal adductor canal catheter placement in patients undergoing TKA may be equally effective for the outcomes of opioid consumption in the first 24 hr, pain scores at rest, and pain scores with movement in the first 24 hr. Nevertheless, TSA findings suggest insufficient power to definitively conclude no differences between the two techniques.

STUDY REGISTRATION

PROSPERO (CRD42022353576); registered 25 August 2022.

Physiotherapy Intervention for Grade 4 Rheumatoid Arthritis Managed With Total Knee Replacement: A Case Report

Inflammatory arthritis and extra-articular involvement remain characteristic features of the systemic autoimmune disease rheumatoid arthritis (RA). Metatarsophalangeal joints, wrists, shoulders, elbows, hips, knees, and ankles are among the joints that are most commonly infected. The patient in this case report is a 30-year-old woman with a history of deformities in both hands and legs. She approached the hospital for an examination, where she was confirmed with grade 4 RA. As the condition was severe in the bilateral knee joint, she was first managed with total knee replacement of the left side. Due to this, there was pain around the left knee joint, and also, there was a restriction in the range of motion of the knee joint; for this, the patient was advised for physiotherapy. The patient was regularly treated for 15 days. We report that physical therapy following the surgery significantly reduced pain intensity, improved the knee joint's range of motion, and increased the strength of the muscles around the knee.

A Systematic Review and Meta-Analysis of Conventional Versus Robotic-Assisted Total Knee Arthroplasty

This study aims to compare the outcomes and advantages of total knee arthroplasty (TKA) performed using conventional surgical techniques with those conducted using robotic-assisted methods in terms of operation time, Oxford knee score, range of motion, tourniquet time, and Western Ontario and McMaster Universities Arthritis index. We performed a literature search through five databases, namely, PubMed, Cochrane Central, Scopus, Embase, and Web of Science, from inception until July 3, 2023. Randomized clinical trials (RCTs) and cohorts comparing conventional TKA with robotic-assisted TKA were included. The risk of bias of the included RCTs was determined using the Cochrane risk of bias tool and the National Institutes of Health tool for cohort studies. We conducted a meta-analysis using Review Manager 5.4. To analyze continuous data, we calculated the mean difference (MD) along with its corresponding 95% confidence interval (CI). By synthesizing data from a comprehensive analysis, the study unveiled noteworthy distinctions between robotic-assisted arthroplasty and conventional arthroplasty across critical parameters. First, a substantial alteration in the hip-knee-ankle (HKA) angle was observed, with the robotic-assisted approach demonstrating a significant difference (MD = 0.84, 95% CI = 0.25-1.43, p = 0.005). Second, in terms of operative time, a notable reduction in surgical duration was noted with conventional TKA (MD = 16.85, 95% CI = 8.08-25.63, p = 0.0002). The assessment of tourniquet time exhibited a significantly longer duration for robotic-assisted arthroplasty (MD = 35.70, 95% CI = 27.80-43.61, p < 0.001). Our findings indicate that conventional TKA outperforms robotic-assisted TKA, primarily due to its shorter operative and tourniquet times, along with a more favorable change in the HKA angle. However, it is worth noting that robotic-assisted TKA showed a slight advantage in pain outcomes, although this advantage was not statistically significant. To gain a more comprehensive understanding, we recommend conducting a large-scale randomized controlled trial that directly compares both TKA methods. This trial should evaluate costs and long-term outcomes while ensuring consistent follow-up durations among studies. Such an approach would greatly assist orthopedic decision-making and contribute to improved TKA outcomes.

Treatment of Bifocal Periprosthetic Fractures above and below a Knee after Tumor using Spanning Ilizarov Device: A Case Report

Introduction

Multiple treatment options and internal and external devices have been recommended for periprosthetic fractures management around total knee arthroplasty.

Case Report

We present the case of the high-energy bifocal periprosthetic fractures of the femur and the tibia after total knee prosthesis following excision of a tumor. One of the fractures was an open tibial fracture Gustilo Type IIIB and the other - comminuted subtrochanteric fracture of the femur with extrusion of periprosthetic cement pieces out from the bone defect. The Ilizarov circular external fixator was used for the skeletal stabilization and early functional treatment in this compound case.

Conclusion

The use of Ilizarov external fixator for patients with complex periprosthetic fractures, who present severe technical difficulties in bone stabilization, especially by concomitant severe soft-tissue damage after high-energy injuries, is a good surgical alternative.

Intrathecal Morphine versus Morphine-Dexmedetomidine Combination for Postoperative Pain Control After Total Knee Replacement: A Randomized Controlled Trial

Objective

This prospective study aimed to compare the analgesic efficacy and adverse effects of intrathecal morphine, dexmedetomidine, and a combination of both in patients undergoing total knee replacement (TKR).

Patients and Methods

This randomized prospective study was carried out in Tanta university hospital in orthopedic surgery for 6 months on 105 adult patients with American Society of Anesthesiologists Physical Status Class II and III, aged > 50 years, and scheduled for total knee replacement surgery randomly allocated into morphine group received 0.5% heavy bupivacaine plus 0.1 mg of morphine, morphine/ dexmedetomidine group, received 0.5% heavy bupivacaine plus 0.1 mg of morphine and 5 mcg of dexmedetomidine and dexmedetomidine group received 0.5% heavy bupivacaine plus 5 mcg of dexmedetomidine. The time of the first required analgesia, postoperative pain severity, the total dose of morphine, postoperative complication, and the patient's level of sedation were recorded.

Results

About half of the patients in the dexmedetomidine group requested first rescue analgesia 6 hours after the operation, significantly shorter than the other two groups. On the other hand, the other two groups show no significant difference between them regarding the first required analgesia. At rest, the dexmedetomidine group have significantly higher VAS with a significant increase in patients who required morphine as rescue analgesia than the other two groups. While at movement, patients in the dexmedetomidine group felt pain at 4 hrs postoperatively with significantly higher VAS than the other two groups. At the same time, the sedation score was significantly lower in the dexmedetomidine group than in the other two groups. 22.2% of cases in the morphine group developed nausea and vomiting with a significant difference between the three groups.

Conclusion

Despite the absence of substantial side effects, our findings did not suggest enhanced analgesia with the combination of intrathecal morphine and dexmedetomidine.

Incidence of Surgical Site Infection Despite Preoperative Cefazolin Administration in Total Knee Arthroplasty Patients: A Tertiary Hospital Experience

INTRODUCTION

Surgical site infection (SSI) is an infection that occurs after surgery on the incision site. Cefazolin is an old-generation antibiotic that decreases the risk of SSI. This study aimed to determine the relationship between the incidence of SSI, cefazolin administration, and the factors contributing to the relationship between them.

METHODS

This is a retrospective study that used a data collection sheet to collect variables from the medical records of patients who underwent total knee arthroplasty (TKA) between 2016 and 2020. We looked mainly for the type of antibiotics given preoperatively, the number of doses given, discontinuation of antibiotics postoperatively, length of hospital stay, intensive care unit (ICU) admission, and SSI occurrence.  Results: A total of 195 patients were included. The majority (87.8%) were given two grams of cefazolin. Patients who have taken one gram of cefazolin had a slightly higher hospital stay than those who took two grams. However, all the patients did not develop an SSI.

CONCLUSION

There was no incidence of SSI despite preoperative cefazolin administration in TKA patients. Patients who received higher doses of cefazolin had a shorter length of hospital stay.

Effective VTE prophylaxis with enoxaparin after elective THR or TKR: a retrospective observational study

Background

Orthopedic patients are at the highest risk for venous thromboembolism (VTE). Nowadays, with VTE prophylaxis as a routine in patients undergoing total hip replacement (THR) and total knee replacement (TKR), fatal pulmonary embolism (PE) is rare and the rates of symptomatic VTE within 3 months dropped to 1.3%-10%, compared with the rates of 50%-70% before VTE prophylaxis implementation. In this study, we aim to evaluate the VTE prophylaxis and incidence in patients who underwent THR and TKR in Centro Hospitalar Universitário de Santo António (CHUdSA).

Methods

We included 483 patients who underwent elective THR or TKR in CHUdSA from March 2019 to February 2020 and who were under enoxaparin as a VTE prophylaxis drug. All data related to prescribed enoxaparin were collected from the nationwide common electronic drug prescription system (PEM).

Results

Of the 483 eligible patients, 192 (39.75%) underwent elective THR and 291 (60.25%) underwent TKR. Enoxaparin was prescribed for 31.86 ± 5.98 and 30.28 ± 5.97 days, on average, for the THR and TKR groups, respectively (P = .005). Patients completed, on average, 29.38 ± 8.12 days and 28.20 ± 7.32 days of VTE prophylaxis with enoxaparin in the THR and TKR groups, respectively (P = .098). The incidence of VTE was approximately 3.13% and 0.69% in the THR and TKR groups, respectively (P = .064).

Conclusion

In CHUdSA, we usually prescribe enoxaparin 40 mg once daily for up to 35 days for VTE prophylaxis after THR or TKR. High therapeutic compliance rates resulted in very few events.

Analysis of Short-Term Clinical and Functional Outcomes in Patients Undergoing Total Knee Arthroplasty with Kinematic Alignment Technique

BACKGROUND

Surgery remains the best option for more advanced stages of knee osteoarthritis (OA). Kinematic alignment (KA) is an innovative surgical technique that aims to co-align the rotational axes of the femoral, tibial, and patella components with the three kinematic axes of the knee. This study aims to evaluate and analyze short-term clinical, psychological, and functional outcomes in patients undergoing total knee replacement with the KA technique.

METHODS

Twelve patients who underwent total knee replacement surgery with kinematic alignment from May 2022 until July 2022 were prospectively followed and interviewed. Before surgery, the day after surgery, and postoperative day 14, the following tests were evaluated: VAS, SF-12 PS, SF-12 MS, KSS, KSS-F, PHQ-9, and KOOS-PS.

RESULTS

The mean BMI value of 30.4 (±3.4) Kg/m², mean age of 71.8 (±7.2) years. All the scores on the various tests administered consistently showed statistically significant improvement, not only immediately after surgery but also comparing the first to the fourteenth postoperative day.

CONCLUSION

Kinematic alignment technique as a surgical treatment for KO allows the patient a fast postoperative recovery and good clinical, psychological, and functional results in a short time. Further studies are needed with a larger sample size, and prospective randomized studies are essential to compare these results with mechanical alignment.

A Randomized Controlled Trial of Kinematically and Mechanically Aligned Total Knee Arthroplasties: Long-Term Follow-Up

BACKGROUND

The optimal alignment technique for total knee arthroplasty (TKA) remains controversial. We previously reported 6-month and 2-year results of a randomized controlled trial comparing kinematically versus mechanically aligned TKA. In the present study, we report the mean 13-year (range, 12.6-14.4) follow-up results from this trial.

METHODS

The original cohort included 88 TKAs (44 kinematically aligned using patient-specific guides and 44 mechanically aligned using conventional instrumentation), performed from 2008 to 2009. After institutional review board approval, the health records of the original 88 patients were queried. Revisions, reoperations, and complications were recorded. There were 26 patients who died, leaving 62 patients for follow-up. Of these, 48 patients (77%) were successfully contacted via phone. Reoperations and complications were documented. Furthermore, a battery of patient-reported outcome measures (PROMs) (including Western Ontario and McMaster University Index, Oxford Knee Score, Knee Injury and Osteoarthritis Outcome Score Junior, Forgotten Joint Score, Modified-Single Assessment Numerical Evaluation, and patient satisfaction) were obtained.

RESULTS

Of the original 88 patients in the study, 15 patients had at least one reoperation (17%) and 5 patients had undergone complete revision surgery (6%). There was no difference between the 2 alignment methods for major and minor reoperations (P = .66). The kinematically aligned total knees self-reported a nonstatistically significant (P = .16) improved satisfaction (96% versus 82%), but no difference in other PROMs compared to mechanically aligned TKAs.

CONCLUSION

Kinematically aligned TKA demonstrates excellent mean 13-year results, comparable to mechanically aligned TKA with similar reoperations, complications, and PROMs.

Learning curve of the 67 steps of conventional total knee replacement: an experimental study

The instrumentation system for total knee replacement (TKR) has been there since the 1970s. The many steps and instruments are the main features despite several modifications over the last 50 years. This may lead to the accumulation of errors as certain steps are dependent on others. This study aimed to identify the errors while performing TKR by three trainees at different levels of training.

Methods

Three trainees with different expertise performed the steps of TKR on bone models. One senior supervisor recorded the outcomes, including operative time and errors made during the experiment. Errors were further categorized into correctable and uncorrectable ones.

Results

Most of the errors were made by the trainee with the least experience during the stages of femoral cutting, sizing, and rotation. The first-year resident has taken 1.25 times longer than the fellow in preparing the femur and 1.11 times in preparing the tibia. The recorded mistakes were 28, 8, and 3 for the first-year resident, the second-year resident, and the fellow surgeon, respectively. Fifteen of the mistakes were uncorrectable, and none of them were from the senior surgeon.

Conclusion

The results of this study highlight the type of errors made by different trainees. This shows the steep learning curve of conventional instrumentation systems for trainees. Increasing cognitive skills and applying computer-assisted technologies may help trainees overcome this steep learning curve.

Pie-Crusting Technique of Medial Collateral Ligament for Total Knee Arthroplasty in Varus Deformity: A Systematic Review

Background

We aimed to better understand the outcomes/complications of pie-crusting technique using blade knife during total knee arthroplasty (TKA) in patients with knee genu varum deformity.

Materials and Methods

A systematic search was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. English and Persian language articles were considered on the use of pie-crusting technique during TKA in patients with knee genu varum/varus deformity using related keywords and Medical Subject Headings terms with reported postoperative complications and outcomes.

Results

Primary search resulted in 81 studies of them 9 included in our study (ages ranged: 19 years to 62 years). No perioperative complications and/or any significant differences between pie-crusting and control group were observed. Except for two studies that found no significant positive effect for the use of pie-crusting, other studies found pie-crusting a useful and promising technique. Four studies found significant improvement in pie-crusting group compared to control in terms of functional Knee Society Score (KSS), range of motion (ROM), medial gap, and the knee-specific KKS. Three records found no significant differences in terms of functional KSS, ROM; however, they reported fewer use of constrained inserts or a reasonable correction of femoral tibial angle. No serious complications were reported.

Conclusions

Due to the inconsistency of the results on the efficiency and outcomes of pie-crusting, we cannot make a firm conclusion and more high-quality studies are needed in this regard. However, this method can be considered as a safe method which depends on the skill of surgeon.

A Retrospective Analysis of the Association Between Male Facial Hair and the Incidence of Peri-Prosthetic Infections

Abstract Background: The wearing of male facial hair has been undergoing something of a renaissance for a number of years, with medical colleagues in the surgical disciplines being no exception. Meanwhile, there are a few reports in the literature that beards might have an increased bacterial colonization. This study aims to determine if wearing a beard leads to an increased rate of infection in total hip or knee arthroplasty. Patients and Methods: A retrospective analysis was performed on 20,394 primary hip and knee replacements that were implanted at a single university hospital. The rate of infections that occurred within one year after surgery and the surgeons performing the surgery were recorded. The surgeons were classified into clean-shaven and beard wearers. The beard wearers were further classified by individual facial hair styles, namely a moustache, chin beard, round beard, or full beard. Results: The overall rate of surgical site infections 365 days after surgery is 0.75%. There was no statistically significant association between surgical site infection and the presence of facial hair (p = 0.774) or specific beard types (p = 0.298). Conclusions: The results presented in this study show no differences in infection rates across different facial hair styles of male surgeons.

Prognostic Factors in Staged Bilateral Total Knee Arthroplasty-A Retrospective Case Series Analysis

BACKGROUND

Bilateral osteoarthritis of the knee is an indication for a bilateral total knee replacement (TKR) procedure. The goal of our study was to assess the sizes of the implants used during the first and second stages of TKR procedures in order to compare their size and identify the prognostic factors for the second procedure.

METHODS

We evaluated 44 patients who underwent staged bilateral TKR procedures. We assess the following prognostic factors from the first and second surgery: duration of anesthesia, femoral component size, tibial component size, duration of hospital stay, tibial polyethylene insert size, and the number of complications.

RESULTS

All assessed prognostic factors did not differ statistically between the first and second TKR. A strong correlation was found between the size of femoral components and the size of tibial components used during the first and second total knee arthroplasty. The mean duration of the hospital stay associated with the first TKR surgery was 6.43 days, whereas the mean duration of the second hospital stay was 5.5 days (p = 0.211). The mean sizes of the femoral components used during the first and second procedures were 5.43 and 5.2, respectively (p = 0.54). The mean sizes of the tibial components used during the first and second TKR procedures were 5.36 and 5.25, respectively (p = 0.382). The mean sizes of the tibial polyethylene inserts used during the first and second procedures were 9.45 and 9.34 (p = 0.422), respectively. The mean duration of anesthesia during the first and second knee arthroplasty was 117.04 min and 118.06 min, respectively (p = 0.457). The mean rates of recorded complications associated with the first and second TKR procedures were 0.13 and 0.06 per patient (p = 0.371).

CONCLUSIONS

We observed no differences between the two stages of treatment in terms of all analyzed parameters. We observed a strong correlation between the size of femoral components used during the first and second total knee arthroplasty. We noted a strong correlation between the size of tibial components used during the first and second procedure. Slightly weaker prognostic factors include the number of complications, duration of anesthesia and tibial polyethylene insert size.

Prognostic models of quality of life after total knee replacement: A systematic review

OBJECTIVE

To systematically review and critically appraise prognostic models for quality of life (QOL) in patients with total knee replacement (TKA).

METHODS

Subjects were TKA recipients recruited from inpatient postoperative settings. Searches were made on June 2022 and updated on April 2023. Databases included PubMed.gov, CINAHL, The Cochrane Library, Web of Science. Two authors performed all review stages independently. Risk of bias assessments on participants, predictors, outcomes and analysis methods followed the Prediction study Risk Of Bias ASsessment Tool (PROBAST).

RESULTS

After screening 2204 studies, 9 were eligible for inclusion. Twelve prognostic models were reported, of which 10 models were developed from data without validation and 2 were both developed and validated. The most frequently applied predictor was the pre-TKA QOL score. Discriminatory measures were reported for 9 (75.0%) models with areas under the curve values of 0.66-0.95. All models showed a high risk of bias, mostly due to limitations in statistical methods and outcome assessments.

CONCLUSION

Several prognostic models have been developed for QOL in patients with TKA, but all models show a high risk of bias and are unreliable in clinical practice. Future, prognostic models overcoming the risk of bias identified in this study are needed.

Comparison of Femoral Component Rotation between Robotic-Assisted vs. Soft-Tissue Tensor Total Knee Arthroplasty with Anatomic Implants

Background and Objectives: Total knee arthroplasty (TKA) is the most effective treatment method for end-stage osteoarthritis. One of the most important aspects of this surgery is adequate implant positioning, as it guarantees the desired outcome of restoring limb biomechanics. Surgical technique is being continuously improved along with hardware development. There are two novel devices designed to help establish proper femoral component rotation: soft-tissue tensor and robotic-assisted TKA (RATKA). This study compared the femoral component rotation achieved with the use of three methods: RATKA, soft tissue tensioner and the conventional measured-resection technique, all of them utilizing anatomical design prosthesis components. Materials and Methods: A total of 139 patients diagnosed with end-stage osteoarthritis underwent total knee arthroplasty between December 2020 and June 2021. After the surgery, they were divided into three groups depending on procedure technique and implant type: Persona (Zimmer Biomet) + Fuzion Balancer, RATKA + Journey II BCS or conventional TKA + Persona/Journey. Postoperatively, a computed tomography examination was performed in order to measure femoral component rotation. All three groups were compared independently during statistical analysis. Fisher's exact, Kruskal-Wallis and Dwass-Steel-Crichtlow-Fligner tests were used for particular calculations. Results: Statistically significant differences in femoral component rotation between groups were noticed. However, in terms of values other than 0° in external rotation, no significant variance was revealed. Conclusions: Additional total knee arthroplasty instruments seem to improve the outcomes of the surgery, providing better component positioning than in the conventional measured-resection technique based only on bone landmarks.

Posterior Compartment Debridement and Varus Deformity Correction in Total Knee Arthroplasty

BACKGROUND

Restoration of joint-line position and deformity correction remain important tenets for preserving stability and function after total knee arthroplasty (TKA). We sought to characterize the role of posterior osteophytes in the correction of alignment deformity during TKA.

METHODS

We evaluated 57 patients (57 TKAs) who participated in a trial of robotic-arm assisted TKA outcomes. Weight-bearing and fixed preoperative alignment was measured using long-standing radiographs and tools of the robotic-arm tracking system, respectively. Total volume (cm²) of posterior osteophytes was quantified using preoperative planning computed tomography scans. Joint line position was evaluated using bone resection thicknesses measured using a caliper.

RESULTS

The mean (minimum to maximum) initial fixed deformity was 4 degrees (range, 0 to 11) of varus. All patients showed asymmetric posterior osteophytes. Mean total osteophyte volume was 3 cm³ (range, 1 to 9). Total osteophyte volume was positively correlated with severity of fixed deformity (r=0.48, P=0.0001). Removal of osteophytes allowed for the correction of functional alignment to within three degrees of neutral in all cases (mean 0 deg), with none requiring release of the superficial medial collateral ligament. Tibial joint line position was restored to within 3 millimeters in all but 2 cases (mean increase of height, 0.6 (range, -4 to +5)).

CONCLUSION

In the end-stage diseased knee, posterior osteophytes typically occupy space in the posterior capsule on the concave side of the deformity. Thorough debridement of posterior osteophytes may help facilitate management of modest varus deformity with decreased need for soft-tissue releases or adjustments to planned bone resection.

Reasons and Risk Factors for Failed Same-Day Discharge After Primary Total Knee Arthroplasty

BACKGROUND

As ambulatory total knee arthroplasty (TKA) becomes increasingly common, unplanned admission after surgery presents a challenge for the health care system. Studies evaluating the reasons and risk factors for this occurrence are limited. We sought to evaluate the reasons for unplanned admission after surgery and identify risk factors associated with this occurrence.

METHODS

Patients registered in an institutional ambulatory joint arthroplasty program who underwent a TKA from 2017-2020 were retrospectively reviewed. The criteria for enrollment include candidates for unilateral TKA between the ages of 18 and 70 years, with a body mass index (BMI) of less than 35, and appropriate social and material support at home. Patients who had certain comorbidities including coronary artery disease, valvular heart disease, and opioid dependence were not eligible. A total of 274 patients who underwent TKA with planned same-day discharge (SDD) were identified in the medical record and reviewed. In this cohort, 140 patients (51.1%) were discharged on the day of surgery and 134 patients (48.9%) required a minimum 1-night admission. Demographics, comorbidities, and perioperative data were collected. Factors associated with failed SDD were identified using multivariate logistic regression.

RESULTS

The most common reasons for failed SDD were failure to meet ambulation goals (25%) and logistical issues related to a late-day case (19%). Risk factors for failed SDD include general anesthesia (odds ratio (OR) 12.60, P = .047), procedure start time after 11:00 am (OR 5.16, P < .001), highest postoperative pain score >8 (visual analogue scale, OR 5.78, P = .001). Willingness to accept a higher pain threshold before discharge (visual analogue scale 4 to 10) was associated with successful SDD (OR 3.0, P < .001). Age and American Society of Anesthesiologists (ASA) classification were not associated with failed SDD.

CONCLUSIONS

The most common reasons for failed SDD were related to logistical issues and postoperative mobilization. Risk factors for failed SDD involve case timing and pain control. Modifiable perioperative factors may play an important role in successful SDD after TKA.

[Effects of a Hybrid Health Education Program on Pain and Knee Angle in Elderly Patients After Total Knee Replacement Surgery]

BACKGROUND

Patients experience pain and limited knee angle after total knee replacement (TKR) surgery. The effectiveness of routine discharge health education remains limited.

PURPOSE

This study was designed to assess the effect of hybrid health education on postoperative pain and knee angle in patients with TKR.

METHODS

A single blind and randomized controlled trial study was used. Fifty-two patients with TKR were randomly assigned to either the experimental group (n = 26), which received standard care with hybrid health education and performed the multimedia-guided intervention for 30 min per day for 16 weeks, or the control group (n = 26), which received routine care only. The data collection times were at pretest (preoperative) and at the 1st week, 6th week, 12th week, 16th week after surgery.

RESULTS

A total of 22 patients in the experimental group and 26 patients in the control group completed this study. After the 16-week hybrid health education intervention, the results of generalized estimating equations analysis showed that pain in the experimental and control groups differed significantly at week 12 (β = -1.43, p = .025) and week 16 (β = -1.52, p = .014); worst pain in the past week had significantly improved at week 12 (β = -1.40, p = .041) and week 16 (β = -1.55, p = .024); average pain over the past 1 week had significantly improved at week 16 (β = -1.24, p = .035); and knee extension angle had significantly improved at week 16 (β = -5.52, p = .033).

CONCLUSIONS / IMPLICATIONS FOR PRACTICE

The results of this study showed that elderly patients who received hybrid health education after TKR had significantly improved postoperative pain and knee angle and that degree of improvement in the experimental group was better than in the control group. It is recommended that the content and methods of hybrid health education developed in this study be incorporated into discharge interventions and that long-term outcomes be tracked for reference.

Racial/Ethnic Disparities in Physical Therapy Utilization After Total Knee Arthroplasty

BACKGROUND

Total knee arthroplasty (TKA) is a common orthopaedic procedure, after which many patients benefit from physical therapy (PT). However, such services may not be uniformly accessible and used. To that end, disparities in access to care such as PT after interventions may be a factor for those of varying race/ethnicities.

METHODS

TKAs were abstracted from the 2014 to 2016 Standard Analytic Files PearlDiver data set-a large national health administrative data set containing information on more than 60 million Medicare patients. Occurrences of home or outpatient PT within 90 days after TKA were identified. Patient demographic factors were extracted, including age, sex, Elixhauser Comorbidity Index, estimated average household income of patient based on zip code (low average household income [<75k/year] or high average household income [>75k/year]), and patient race/ethnicity (White, Hispanic, Asian, Native American, Black, or Other). Predictive factors for PT utilization were determined and compared with univariate and multivariate analyses.

RESULTS

Of 23,953 TKA patients identified, PT within 90 days after TKA was used by 18,837 (78.8%). Patients self-identified as White (21,824 [91.1%]), Black (1,250 [5.2%]), Hispanic (268 [1.1%]), Asian (241 [1.0%]), Native American (90 [0.4%]), or "Other" (280 [1.2%]) and were of low household income (19,957 [83.3%]) or high household income (3,994 [16.7%]). When controlling for age, sex, and ECI, PT was less likely to be received by those of low household income (relative to high household income OR 0.79) or by those of defined race/ethnicity (relative to White or Black OR 0.81, Native American OR 0.58, Asian OR 0.50, or Hispanic OR 0.44) ( P < 0.05 for each).

DISCUSSION

In a large Medicare data set, disparities in utilization of PT after TKA were identified based on patient's estimated household income and race/ethnicity. Identification of such factors may help facilitate the expansion of care to meet the needs of all groups adequately.

LEVEL OF EVIDENCE

Level III.

How Back Pain Affects Patient Satisfaction After Primary Total Knee Arthroplasty

BACKGROUND

Although back pain (BP) has been shown to be a predictor of dissatisfaction after total knee arthroplasty (TKA) in some reports, these studies did not use a scale to quantify the degree of pain. The purpose of this study was to quantify the effect of BP intensity on patient satisfaction reported at 1 year after TKA.

METHODS

A multicenter prospective cohort was taken in which 9,057 patients undergoing primary unilateral TKA were enrolled in FORCE-TJR and demographic and clinical data were collected. Back pain (BP) intensity was assessed using the Oswestry back disability index (ODI) pain intensity questionnaire. Patients were classified into 4 categories based on the severity of BP. Patient-reported outcomes (PROs) were collected preoperatively and postoperatively after 1 year including the Knee injury and Osteoarthritis Outcome Score (KOOS) (total score, pain, Activities of Daily Living (ADL), and Quality of Life (QOL), Short-Form health survey 36-item (SF-36) Physical Component Score (PCS), and Mental Component Score (MCS)). We used a validated 5-point Likert satisfaction scale. Univariate analyses of the difference between the satisfied and dissatisfied patients' groups was performed. Multivariate logistic regression models with 95% confidence interval (CI) were used to quantify the effect of BP intensity on patient dissatisfaction at 1 year. Receiver operating characteristic (ROC) analyses were performed with measurement of area under curve (AUC).

RESULTS

At 1 year, a total of 1,657 TKA patients (18.3%) were dissatisfied. A total of 4,765 patients (52.6%) reported back pain at the time of surgery, including mild BP in 2,264 patients (24.9%), moderate BP in 1,844 patients (20.3%), and severe BP in 657 patients (7.2%). Severe back pain was significantly associated with patient dissatisfaction at 1 year after TKA (P = .0006). The multivariate regressions showed that patients who had severe BP were 1.6 times more likely to be dissatisfied when compared to patients who had no BP [odds ratio (OR) 1.63; 95% confidence interval (CI) (1.23-2.16), P = .0006]. While patients who had mild BP [OR 0.98; 95% CI (0.82-1.17), P = .87] or moderate BP [OR 0.97; 95% CI (0.80-1.18), P = .78] were not associated with an increased likelihood of dissatisfaction. Other predictive variables for dissatisfaction, include age [OR for younger patients <65 years versus older patients ≥65 years, 0.74; 95% CI (0.59-0.92)], educational level [OR for post high school versus less, 0.83; 95% CI (0.71, 0.97)], smoking [OR for nonsmoker versus current smoker, 0.63; 95% CI (0.45, 0.87)], and Charlson comorbidity index [OR for CCI ≥2 versus 0, 1.25; 95% CI (1.05, 1.49)].

CONCLUSION

Increased BP intensity was associated with increased risk of dissatisfaction 1 year after TKA. Only patients who had severe BP were 1.6 times more likely to be dissatisfied. The data presented here can help to improve shared decision-making and patient counseling before surgery. Surgeons should consider a spine evaluation in patients who have severe BP prior to TKA.

Total Joint Arthroplasty Utilization After Orthopaedic Surgery Referral: Identifying Disparities Along the Care Pathway

BACKGROUND

Although racial and ethnic disparities in total joint arthroplasty (TJA) have been thoroughly described, only a few studies have sought to determine exactly where along the care pathway these disparities are perpetuated. The purpose of this study was to investigate disparities in TJA utilization occurring after patients who had diagnosed hip or knee osteoarthritis were referred to a group of orthopaedic providers within an integrated academic institution.

METHODS

A retrospective, multi-institutional study evaluating patients with diagnosed hip or knee osteoarthritis was conducted between 2015 and 2019. Information pertaining to patient demographics, timing of clinic visits, and subsequent surgical intervention was collected. Utilization rates and time to surgery from the initial clinic visit were calculated by race, and logistic regressions were performed to control for various demographic as well as health related variables.

RESULTS

White patients diagnosed with knee osteoarthritis were significantly more likely to receive total knee arthroplasty (TKA) than Black and Hispanic patients, even after adjusting for various demographic variables (Black patients: odds ratio [OR] = 0.63, 95% CI = 0.55-0.72, P = .002; Hispanic patients: OR = 0.69, 95% CI = 0.57-0.83, P = .039). Similar disparities were found among patients diagnosed with hip osteoarthritis who underwent total hip arthroplasty (THA; Black patients: OR = 0.73, 95% CI = 0.60-0.89, P = <.001; Hispanic patients: OR = 0.72, 95% CI = 0.53-0.98, P <.001). There were no differences in time to surgery between races (P > .05 for all).

CONCLUSION

In this study, racial and ethnic disparities in TJA utilization were found to exist even after referral to an orthopaedic surgeon, highlighting a critical point along the care pathway during which inequalities in TJA care can emerge. Similar time to surgery between White, Black, and Hispanic patients suggest that these disparities in TJA utilization may largely be perpetuated before surgical planning while patients are deciding whether to undergo surgery. Further studies are needed to better elucidate which patient and provider-specific factors may be preventing these patients from pursuing surgery during this part of the care pathway.

LEVEL OF EVIDENCE

Level IV.

Shear wave tensiometry tracks reductions in collateral ligament tension due to incremental releases

Surgeons routinely perform incremental releases on overly tight ligaments during total knee arthroplasty (TKA) to reduce ligament tension and achieve their desired implant alignment. However, current methods to assess whether the surgeon achieved their desired reduction in the tension of a released ligament are subjective and/or do not provide a quantitative metric of tension in an individual ligament. Accordingly, the purpose of this study was to determine whether shear wave tensiometry, a novel method to assess tension in individual ligaments based on the speed of shear wave propagation, can detect changes in ligament tension following incremental releases. In seven medial and eight lateral collateral porcine ligaments (MCL and LCL, respectively), we measured shear wave speeds and ligament tensions before and after incremental releases consisting of punctures with an 18-gauge needle. We found that shear wave speed squared decreased linearly with decreasing tension in both the MCL (average coefficient of determination (R2 avg ) = 0.76) and LCL (R2 avg  = 0.94). We determined that errors in predicting tension following incremental releases were 26.2 and 14.2 N in the MCL and LCL, respectively, using ligament-specific calibrations. These results suggest shear wave tensiometry is a promising method to objectively measure the tension reduction in released structures. Clinical Significance: Direct, objective measurements of the tension changes in individual ligaments following release could enhance surgical precision during soft tissue balancing in total knee arthroplasty. Thus, shear wave tensiometry could help surgeons reduce the risk of poor outcomes associated with overly tight ligaments, including residual knee pain and stiffness.

Are 20% of Patients Actually Dissatisfied Following Total Knee Arthroplasty? A Systematic Review of the Literature

BACKGROUND

Total knee arthroplasty (TKA) is among the most performed orthopaedic surgeries in the United States with at least 1,000,000 cases performed per year. Dissatisfaction following TKA has often been reported as 20% or more, with a multitude of causes including sociodemographic, preoperative, and postoperative factors. The purpose of this study was to re-examine the rate and causes of dissatisfaction following TKA.

METHODS

A systematic review of the literature was performed searching databases from 2010 to 2022. Only primary TKA cases were included and all cases of unicompartmental arthroplasty and revisions were excluded. After abstracts were reviewed, 35 articles were selected for a full-length review, which was ultimately reduced to 21 articles for final inclusion.

RESULTS

The average rate of patient dissatisfaction was 10%. Excluding complications, the average rate of dissatisfaction was 7.3%. The most common sociodemographic factors for dissatisfaction were age < 65 years, lower income, and non-White patients. Preoperative factors included lower Kellgren-Lawrence scores, depression/anxiety, and pain catastrophizing. Postoperatively, most dissatisfaction was due to complications, unmet expectations, persistent pain, and stiffness.

CONCLUSION

Based on our review, the average rate of patient dissatisfaction following TKA is 10%. Improved counseling for known risk factors may have reduced dissatisfaction rates by increasing preoperative patient optimization. Many studies in recent years have demonstrated the issue of poor patient coping skills, such as pain catastrophizing and anxiety/depression as a common cause of dissatisfaction. Ultimately, dissatisfaction following TKA still continues to affect a high portion of patients but less than historical reports of 20%.

Patient-Reported Outcomes following Total Knee Replacement in Patients Aged 65 Years and Over-A Systematic Review

A previous systematic review showed positive patient-reported outcomes following total knee replacement (TKR) in patients aged < 65 years. However, the question remains as to whether these results are replicated for older individuals. This systematic review evaluated the patient-reported outcomes following TKR in individuals aged ≥ 65 years. A systematic search of Ovid MEDLINE, EMBASE, and Cochrane library were performed to identify studies examining disease-specific or health-related quality of life outcomes following TKR. Qualitative evidence synthesis was performed. Eighteen studies with low (n = 1), moderate (n = 6), or serious (n = 11) overall risk of bias were included, with evidence syntheses derived from 20,826 patients. Four studies reported on pain scales, showing improvement of pain from 6 months to 10 years postoperatively. Nine studies examined functional outcomes, showing significant improvements from 6 months to 10 years after TKR. Improvement in health-related quality of life was evident in six studies over 6 months to 2 years. All four studies examining satisfaction reported overall satisfaction with TKR results. TKR results in reduced pain, improved function, and increased quality of life for individuals aged ≥ 65 years. The improvement in patient-reported outcomes needs to be utilised in conjunction with physician expertise to determine what would comprise clinically significant differences.

A Rare Presentation of Patella Button Aseptic Loosening After a Total Knee Replacement Without Evidence of Radiographic Loosening

Patella resurfacing in total knee replacement (TKR) has been shown to reduce the rate of anterior knee pain, but there are complications from patella resurfacing. A 54-year-old male underwent a left primary TKR with patella resurfacing 15 years ago. He developed spontaneous progressive anterior knee pain for six months. At revision surgery, his patella button was found to be loose. Loosening of a three-peg patella button is rare. A high index of suspicion of patella button loosening should be suspected in patients who present with anterior knee pain after patella resurfacing.