Establishing minimum clinically important difference values for the Patient-Reported Outcomes Measurement Information System Physical Function, hip disability and osteoarthritis outcome score for joint reconstruction, and knee injury and osteoarthritis outcome score for joint reconstruction in orthopaedics

Increasing Body Mass Index Not Associated With Worse Patient-Reported Outcomes After Primary THA or TKA

INTRODUCTION

As the US obesity epidemic continues to grow, so too does comorbid hip and knee arthritis. Strict body mass index (BMI) cutoffs for total hip and knee arthroplasty (THA and TKA) in the morbidly obese have been proposed and remain controversial, although current American Academy of Orthopaedic Surgeons guidelines recommend a BMI of less than 40 m/kg 2 before surgery. This study sought to compare patient-reported outcomes and 30-day complication, readmission, and revision surgery rates after THA or TKA between morbidly obese patients and nonmorbidly obese control subjects.

METHODS

All patients undergoing primary THA and TKA at our institution from May 2020 to July 2022 were identified. Patient demographics, surgical time, length of stay and 30-day readmission, revision surgery, and complication rates were prospectively collected. Preoperative and postoperative Hip and Knee Society (Hip Osteoarthritis Outcome Score [HOOS] and Knee Osteoarthritis Outcome Score [KOOS]) were collected. Patients were stratified by BMI as ideal weight (20 to 24.9), overweight (25 to 29.9), class I obese (30 to 34.9), class II obese (35 to 39.9), and morbidly obese (>40 m/kg 2 ).

RESULTS

A total of 1,423 patients were included for final analysis. No difference was observed in 30-day unplanned return to emergency department, readmission, or revision surgery in the morbidly obese cohort. Morbidly obese patients undergoing THA had lower preoperative HOOS (49.5 versus 54.5, P = 0.004); however, there was no difference in postoperative HOOS or KOOS at 12 months across all cohorts.

DISCUSSION

No difference was observed in 30-day return to emergency department, readmission, or revision surgery in the morbidly obese cohort. Despite a lower preoperative HOOS, there was no difference in 12-month HOOS or KOOS when stratified by BMI. These findings suggest that such patients may achieve similar benefit from arthroplasty as their ideal weight counterparts.

Variation in Demographics, Hospital, and Patient-Reported Outcomes Following Total Hip Arthroplasty According to Biological Sex

BACKGROUND

The effect of biological sex on the outcomes of total hip arthroplasty (THA) remains unclear. Accounting for biological sex in research is crucial for reproducibility and accuracy. Average combined data may mask sex-related variation and obscure clinically relevant differences in outcomes. The aim of this study is to investigate hospital and patient-reported outcome measures (PROMs) after THA by biological sex to elucidate differences and ultimately provide more equitable care.

METHODS

We performed a retrospective review of patients undergoing primary THA at a single large academic center between January 2013 and August 2020. Demographics, operative variables, hospital outcomes, and PROMs were compared between men and women patients. The PROMs included preoperative, 6-weeks, 6-months, and 1-year Single Assessment Numeric Evaluation, Visual Analog Scale, Hip Disability and Osteoarthritis Outcome Score Joint Replacement, University of California, Los Angeles, and Patient-Reported Outcomes Measurement Information System mental and physical scores, as well as satisfaction scores.

RESULTS

A total of 6,418 patients were included (55% women). Women were older (P < .001), had a lower body mass index (P < .001), and were more likely to have public insurance (P < .001). Fewer women were discharged to home or self-care (P < .001). Women had higher rates of cementation (P < .001) and fracture within 90 days (P < .001), and these associations remained significant with adjusted multivariable analyses. Women had significantly higher pain and lower functional scores preoperatively; postoperatively, most PROMs were equivalent.

CONCLUSIONS

Important differences were observed in several areas. Demographic parameters differed, and a variable effect of biological sex was observed on surgical and hospital outcomes. Women had an increased incidence of cemented femoral components (indicated for osteoporotic bone) and postoperative fractures. Women's PROMs demonstrated globally lower functional scores and higher pain preoperatively. Differences attributed to sex should continue to be investigated and accounted for in risk-stratification models. Future studies are needed to elucidate the underlying causes of observed biological sex differences and are essential for equitable arthroplasty care.

Evaluating the impact of robotic-assisted total knee arthroplasty on quality of care through patient-reported outcome measures in a third-level hospital in Italy: A prospective cohort study

BACKGROUND

With the shift towards personalized medicine, understanding the impact of robotic-assisted total knee arthroplasty (TKA) on patient-reported outcome measures (PROMs) is essential for evaluating its effectiveness and patient satisfaction. The QUAROB (Quality-assessment-of-ROBotic-orthopedic-surgery) study aims at assessing the impact of robotic surgery on quality of care and joint functionality at 6 months post-surgery among patients undergoing robotic-assisted TKA.

METHODS

This observational, prospective cohort study included patients from Ravenna Hospital, Italy, who underwent elective robotic TKA (2022-2023), and a historical cohort who underwent traditional TKA (2019). PROMs questionnaires (EuropeanQualityofLife-Visual AnalogScale, EQ-VAS, EuropeanQualityofLife-5Dimensions-3Likert, EQ-5D-3L, and KneeinjuryOsteoarthritisOutcomeScore-PatientSatisfaction, KOOS-PS) were administered within 30 days before surgery and 6 months post-surgery. Statistical analysis involved comparing baseline and follow-up PROMs, focusing on patients achieving at least a 10% improvement (Minimal Clinically Important Difference, MCID).

RESULTS

The study enrolled 214 robotic surgery patients, with 208 completing baseline and 103 completing 6-month follow-up questionnaires. Patients undergoing robotic-assisted TKA demonstrated significant improvements in EQ-VAS, EQ-5D-3L, and KOOS-PS scores at 6 months. A significant proportion of patients achieved improvements exceeding the MCID threshold (68.9% for EQ-VAS, 58.3% for EQ-5D-3L, and 68.9% for KOOS-PS). Robotic TKA patients experienced shorter hospital stays (7 vs. 9 days, p < 0.001) and higher engagement in rehabilitation compared to traditional TKA patients.

CONCLUSIONS

The QUAROB study provides evidence of the impact and benefits of robotic-assisted TKA, highlighting significant enhancements in PROMs, reduced hospital stays, and increased rehabilitation engagement. These outcomes reinforce the role of robotic technology in improving surgical precision and patient satisfaction in orthopedic surgery.

How Should We Define Meaningful Improvement? A Commentary on Minimal Clinically Important Difference Assessment for Hip Disability and Osteoarthritis Outcome Score for Joint Replacement and Knee Injury and Osteoarthritis Outcome Score for Joint Replacement in Total Joint Arthroplasty

Minimal clinically important difference (MCID) thresholds guide clinicians and researchers in determining whether changes in patient-reported outcome measures are truly meaningful from the patient's perspective. This article focuses on MCID calculation methods for the Hip Disability and Osteoarthritis Outcome Score for Joint Replacement and the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, two widely used patient-reported outcome measures in total hip and total knee arthroplasty. While distribution-based methods (e.g., the half-standard deviation threshold) are common for their simplicity and lack of extra data requirements, they are limited by reliance on statistical properties rather than patient perception. In contrast, anchor-based methods, endorsed by the Consensus-based Standards for the Selection of Health Measurement Instruments, use external "anchors" such as satisfaction or quality-of-life measures to capture the patient's view of improvement. Predictive modeling, a sophisticated anchor-based technique, is particularly robust, producing smaller confidence intervals and adjusting for various patient characteristics. However, all anchor-based approaches depend heavily on the choice and quality of the anchor, highlighting a need for standardization and validation of these external measures. Moreover, MCID thresholds are population-specific and can vary according to baseline function, comorbidities, demographics, and surgical context. Ceiling effects in both Hip Disability and Osteoarthritis Outcome Score for Joint Replacement and Knee Injury and Osteoarthritis Outcome Score for Joint Replacement further complicate MCID assessment. To address these challenges, the article recommends prioritizing anchor-based methods, standardizing anchors, and interpreting MCID values within each study's clinical context. Comprehensive reporting of baseline characteristics and instrument sensitivity (including ceiling effects) is also essential for reliable comparisons and evidence-based practice.

Evaluating the effectiveness of interlaminar epidural steroid injections for cervical radiculopathy using PROMIS as an outcome measure

Background

Cervical interlaminar epidural steroid injections (CIESI) are frequently used to treat cervical radiculopathy due to cervical nerve root impingement.

Objective

The purpose of this study was to evaluate the therapeutic effect of CIESI for patients with cervical radiculopathy.

Methods

We conducted a retrospective review of consecutive adult patients with cervical radicular pain and corroborative cervical spondylotic foraminal stenosis on MRI that failed at least 6 weeks of conservative management consisting of medication and physical rehabilitation seen at a multidisciplinary, tertiary academic spine center. Patient Reported Outcome Measurement Information System (PROMIS) domains of Physical Function (PF) v1.2/v2.0 and Pain Interference (PI) v1.1 were collected at all patient visits. Scores were recorded at baseline, 3-months, 6-months and 12-months post-procedure. Statistical analysis comparing baseline scores with follow-up postprocedural PROMIS scores was performed. The percentage of patients reporting improvement greater than the minimal clinically important difference (MCID) was calculated for responders and for the worst case scenario.

Results

179 patients met inclusion criteria. PROMIS PI at 3-, 6-, and 12-month follow-up statistically improved by 1.5 (95 % confidence interval [CI] 1.4-1.6; p = 0.02), 1.5 (95 % CI 1.4-1.6; p = 0.03) and 1.7 (95 % CI 1.6-1.8; p = 0.4), respectively. Follow-up PROMIS PF at 3-month follow-up improved by 1.6 (95 % CI 1.5-1.7; p = 0.04) but did not significantly differ at 6- or 12-month follow-up. The percentage of patients that exceeded MCID thresholds of clinical significance was 44 % (95 % CI 36%-53 %) at 3-months, 49 % (95 % CI 39%-59 %) at 6-months, and 54 % (95 % CI 41%-66 %) at 12-months. Worst case scenario analysis demonstrated that 32 % (95 % CI 36%-53 %) of patients exceeded the MCID thresholds at 3-months, 31 % (95 % CI 24%-37 %) at 6-months, and 21 % (95 % CI 15%-27 %) at 12-months.

Discussion/conclusions

Our study demonstrated that CIESI leads to an improvement in function and pain for patients with cervical radiculopathy. This study was limited by retrospective design, loss to follow-up, and variation in steroids used.

Current Use of Patient-Reported Outcome Measures Ignores Functional Demand

INTRODUCTION

Patient-reported outcome measures (PROMs) are used in orthopaedic surgery to measure aspects of musculoskeletal function that are important to patients, such as disability and pain. However, current assessments of function using PROMs do not necessarily consider a patient's functional demands in detail. A patient's functional demands could serve as a confounder to their perception of their functional ability. Hence, functional demands may need to be adjusted for when PROMs are used to measure musculoskeletal function.

METHODS

We conducted a cross-sectional study in which new orthopaedic patients completed a questionnaire regarding demographics, function [Patient-Reported Outcomes Measurement Information System], functional demand (Tegner Activity Level Scale), pain self-efficacy, and symptoms of depression. 169 eligible patients with diverse orthopaedic conditions were enrolled in the study from an orthopaedic clinic, and 19 were excluded for incomplete questionnaires.

RESULTS

The mean Patient-Reported Outcomes Measurement Information System score was 36.5 ± 9.1, and the mean Tegner score was 2.6 ± 2.0. In the multivariable regression model, patient-reported function was significantly associated with functional demand (β = 0.17, P < 0.001). Significant associations were observed for pain self-efficacy (β = 0.15, P < 0.001), acuity (β = -0.10, P = 0.004), and age 80 years or older (β = -0.16, P = 0.004). No notable association was observed with depression or age 65 to 79 years.

DISCUSSION

Higher patient-reported physical function is associated with higher levels of functional demand when controlling for psychosocial factors, acuity, and age. Because of its confounding effect on measuring physical function, functional demand should be assessed and included in models using PROMs before and after surgery. For example, payment models using improvements in PROMs, such as the short form of the Hip dysfunction and Osteoarthritis Outcome Score and the Knee injury and Osteoarthritis Outcome Score after joint arthroplasty, should include functional demand in the model when assessing quality of care.

LEVEL OF EVIDENCE

Level II.

Evaluating Patient-Reported Outcome Measure Collection and Attainment of Substantial Clinical Benefit in Total Joint Arthroplasty Patients

BACKGROUND

Patient-reported outcome measures (PROMs) are important markers of postsurgical outcomes following total joint arthroplasty (TJA). Recent policies by the Centers for Medicare & Medicaid Services will require hospitals to achieve at least 50% postoperative PROM collection rates in order to qualify for their full annual payment in fiscal year 2028. This study aimed to: (1) quantify provider PROMs collection rates for TJA patients; (2) compare mean improvements in postoperative PROMs in TJA patients; (3) identify the proportion of TJA patients achieving substantial clinical benefit (SCB); and (4) identify factors associated with TJA patient completion of matched PROMs and achievement of SCB at one year.

METHODS

This retrospective cohort study included 1,493 primary total hip arthroplasty (THA) and 2,959 primary total knee arthroplasty (TKA) patients who underwent surgery at a single institution from May 2019 to December 2023. The primary outcomes were 1-year paired hip or knee PROM collection, measured by the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement and Hip Disability and Osteoarthritis Outcome Score for Joint Replacement surveys, and SCB achievement rates (22 for Hip Disability and Osteoarthritis Outcome Score for Joint Replacement and 20 for Knee Injury and Osteoarthritis Outcome Score for Joint Replacement). Secondary outcomes involved identifying factors associated with PROM completion and SCB achievement. Statistical analyses included descriptive statistics, t-tests, and logistic regression analysis.

RESULTS

There were 61.2% of THA patients and 61.1% of TKA patients who completed 1-year paired PROMs, with 72.8% of THA and 53.3% of TKA patients achieving SCB. Factors associated with higher PROMs completion included technology use (PROMs application, text reminders). For TJA patients, a lower preoperative PROM was associated with achievement of SCB at one year. For THA patients, lower body mass index was associated with SCB attainment. For TKA patients, men were significantly associated with SCB attainment.

CONCLUSIONS

The study indicates compliance with the 50% PROM collection requirement, but this required significant allocation of resources, including the use of a digital care platform. Substantial clinical benefit was achieved in 72.8% of THA patients but only 53.3% of TKA patients at one year, and this was associated with certain patient demographic factors. Achieving compliance with the Centers for Medicare & Medicaid Services requirement may be difficult for many providers and institutions.

Patient-reported outcomes in total hip arthroplasty for patients with anatomically contoured femoral heads

INTRODUCTION

Iliopsoas tendinitis after total hip arthroplasty (THA) has become more prevalent with the increased use of large-diameter femoral heads impinging on native surrounding tissues. Anatomically contoured heads (ACH) are soft-tissue-friendly femoral heads created to minimise this issue. This retrospective study assesses iliopsoas tendinitis prevalence and re-operations in primary THAs with ACH, while determining the minimal clinically important difference (MCID) achievement and improvement with 5 patient-reported outcome measures (PROMs).

METHODS

We conducted a retrospective analysis of 53 ACHs from January 2020 to July 2023. Patients who completed Hip Injury and Osteoarthritis Outcome Score-Physical Function Short Form (HOOS-PS), Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function Short Form 10a (PF SF-10a), PROMIS Global Health (GH)-Mental, or PROMIS GH-Physical, and pain score questionnaires were identified. PROM scores were collected preoperatively and at 3-month and 1-year postoperative intervals. Comparisons using chi-square and ANOVA tests were applied.

RESULTS

The rates of achieving MCID and improvement within the first year were (69.2 vs. 76.9%) for PROMIS GH-Physical, (38.5 vs. 46.2%) for PROMIS GH-Mental, (71.4 vs. 92.9%) for HOOS-PS, (80.0 vs. 80.0%) for PROMIS PF SF-10a, and (74.0 vs. 91.7%) for pain scores. PROM scores at 3 months and 1 year significantly varied across all categories, except for PROMIS GH-Mental. No patients had iliopsoas tendinitis, dislocations, or re-operations.

DISCUSSION

ACH implants may alleviate anterior hip pain, while maintaining comparable strength and bio-compatibility to conventional femoral heads. This study underscores the early safety and potential of ACH implants in reducing iliopsoas tendinitis and impingement.

Clinical relevance of patient-reported outcome measures in patients who have undergone total hip arthroplasty: a systematic review

INTRODUCTION

In orthopaedic research, it is crucial to determine changes that are statistically significant and clinically meaningful. One approach to accomplish this is by calculating the Minimal Clinically Important Difference (MCID), the Clinically Important Differences (CID), the Minimum Detectable Change (MDC), the Minimal Important Change (MIC), and the Patient Acceptable Symptom State (PASS) values. These tools assist medical professionals in comprehending the patient's viewpoint, enabling them to establish treatment objectives that align with patients' desires and expectations. The present systematic review investigated the MCID, MIC, CID, MDC, and PASS of the most used PROMs to assess patients who have undergone THA.

METHODS

This systematic review followed the 2020 PRISMA guidelines. Web of Science, Embase, and PubMed were accessed in March 2024 without time constraints or additional filters. All the clinical investigations which evaluated data tools (MCID, MIC, CID, MDC, and PASS) to assess the clinical relevance of PROMs in THA were accessed. Articles in Spanish, Italian, German, and English were eligible. Studies with levels of evidence I to III were eligible.

RESULTS

Data from 100,824 patients were collected. All relevant demographic data were analysed and summarised. In addition, the MCID, MIC, CID, MDC and PASS of the COMI, HOOS, SF-36, OHS, Oxford-12, PROMIS-PF, SF-12, and WOMAC scores for THA were determined.

CONCLUSION

Current evidence recommends to collect MCIDs based on anchors routinely. These values should be used as complementary tools to determine the clinical effectiveness of a treatment instead of solely relying on statistically significant improvements.

LEVEL OF EVIDENCE

Level IV, systematic review and meta-analysis.

Effect of Race and Socioeconomic Status on the Attainment of Substantial Clinical Benefit on Patient-Reported Outcome Measures Following Total Joint Arthroplasty

BACKGROUND

Utilization of and access to total joint arthroplasty (TJA) are disproportionately skewed in patients who have low socioeconomic status (SES) and in minority populations. Patient-reported outcome measures (PROMs) are critical markers of post-surgical outcomes following TJA. This study aimed to: 1) evaluate differences in race, SES, and demographic factors between TJA patients who achieved substantial clinical benefit (SCB) and those who did not; 2) assess differences between preoperative PROMs in these patients; and 3) identify whether race and SES are associated with SCB achievement at 1-year post-TJA.

METHODS

This retrospective cohort study included 1,154 total hip arthroplasty (THA) and 1,879 total knee arthroplasty (TKA) patients who underwent surgery at a single academic medical center from May 2019 to February 2023. Preoperative and postoperative PROMs were collected using the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement and Hip Disability and Osteoarthritis Outcome Score for Joint Replacement surveys. Demographic and comorbidity data were collected from charts. Multivariable logistic regression analyzed the association between predictive variables and SCB achievement.

RESULTS

No differences in race were found between patients who achieved SCB and those who did not for both TKA and THA (P > 0.05). However, preoperative Knee Injury and Osteoarthritis Outcome Score for Joint Replacement scores were lower in Black (P = 0.004) and Hispanic (P < 0.001) patients and preoperative Hip Disability and Osteoarthritis Outcome Score for Joint Replacement scores were lower in Black patients (P < 0.001) than White patients. A higher proportion of patients in the lowest income category achieved SCB for both THA and TKA than those in other income categories (P = 0.04, P = 0.03, respectively). However, race was not associated with SCB likelihood at one year. For TKA patients, men were negative, and bilateral simultaneous TKA was positively associated with SCB achievement when controlling for race, income, and body mass index (P < 0.001, P = 0.01, respectively).

CONCLUSIONS

Race and income category were not significantly associated with achieving SCB at one year among TJA patients. However, non-White patients had a similar likelihood of achieving SCB as White patients, even with lower preoperative PROMs, indicating that these patients may benefit greatly from TJA despite delays in care. Men were negatively associated with TKA SCB achievement, while bilateral simultaneous TKA was positively associated with SCB.

The Impact of Travel Distance on Patient-Reported Outcomes Following Primary Total Hip Arthroplasty

BACKGROUND

Total hip arthroplasties (THAs) are increasingly being performed at high-volume centers, causing some patients to travel further distances to receive care. Concerns remain that increased travel distance limits follow-up, which may impact outcomes and early return to the hospital. The purpose of this study is to evaluate the impact of travel distance on 90-day patient-reported outcomes (PROs) and 90-day complication rates.

METHODS

Patients undergoing inpatient primary THA at a single center by one of three surgeons between 2017 and 2021 were retrospectively reviewed. Patients whose local and distant medical records were available were included. Patients who lived ≥ 40 miles from the location or follow-up were labeled as "travelers," and those < 40 miles were "locals." Primary outcomes included PROs as measured by Veterans Rand 12 Item Health Survey, Harris Hip Score, and Hip Dysfunction and Osteoarthritis Outcome Score for Joint Replacement. Secondary outcomes included rates of 90-day medical complications, emergency department visits, unplanned readmissions, and reoperations.

RESULTS

A total of 413 patients were analyzed at a mean of 897.1 days (range, 92 to 2,196) including 96 travelers. Travelers averaged 96.1 miles for follow-up (range, 40.1 to 678 miles), and locals averaged 14.1 miles for follow-up (range, 0.3 to 39.8 miles). There were no differences in the percentage of patients achieving minimal clinically important difference in PROs. There was no difference in the rate of 90-day medical complications, 90-day readmissions, and reoperations. Local patients were significantly more likely to have unplanned postoperative emergency department visits (travelers = 0%, locals = 7.4%, P = 0.003).

CONCLUSIONS

Travelers did not demonstrate any significant differences with respect to rates of achieving minimal clinically important difference in PROs or 90-day complication rates. These data suggest that increased travel distance to treatment centers does not impact outcomes following primary THA.

MCID achievement in staged bilateral total knee arthroplasty: Are both joints created equal?

BACKGROUND

A notable portion of unilateral total knee arthroplasty (TKA) patients undergo arthroplasty of the contralateral knee. The aims of this study were to describe the Minimal Clinically Important Difference for Improvement (MCID-I) and Worsening (MCID-W) in staged bilateral TKAs (BTKAs) and identify factors associated with these outcomes.

METHODS

Patients with staged BTKA were retrospectively reviewed. Demographics, surgery details, and Patient-Reported Outcome Measurement Information System Physical Function Short Form 10a (PROMIS PF10a) were collected. MCID-I and MCID-W were defined for PROMIS PF10a. Patients were stratified into nine groups based on the MCID achievement of the first and second TKA: (A) MCID-I, MCID- I, (B) MCID-I, Neutral, (C) MCID-I, MCID-W, (D) Neutral, MCID-I, (E) Neutral, Neutral, (F) Neutral, MCID-W, (G) MCID- W, MCID-I, (H) MCID-W, Neutral, (I) MCID-W, MCID-W. Neutral patients did not achieve either MCID-I or MCID-W.

RESULTS

The final cohort consisted of 59 staged BTKA patients. In patients who achieved MCID-I in the first TKA, 39.1% achieved MCID-I again in the second TKA (A), 39.1% were neutral (B), and 21.7% achieved MCID-W (C) in the second TKA. However, 77.8% of those who achieved MCID-W in the first joint (n = 9) went on to achieve MCID-I (G) in the second TKA. Those who achieved MCID-I after both TKAs (A) had a longer staged interval than those who achieved first MCID-I, then MCID-W (C) (15 months vs 8 months, P = 0.0113).

CONCLUSION

In staged BTKA, MCID achievement of the first TKA may not be associated with the outcome of the second TKA.

Functional Outcomes of Robotic-Assisted Total Knee Arthroplasty in Severe Varus Deformities of the Knee in the Indian Population

PURPOSE

Correction of severe coronal plane deformities while performing a total knee arthroplasty (TKA) is challenging. The use of functional alignment (FA) strategy along with image-based robotic technology during TKA makes it possible to restore a patient's constitutional alignment with minimal or no soft tissue release. The present study aims to report the functional outcomes of robotic-assisted TKA in Indian patients with severe varus deformity.

METHODS

This retrospective study included 82 primary TKA performed by a single senior arthroplasty surgeon from January 2022 to December 2022. The Visual Analogue Score for Pain (VAS-P) and the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS-JR) were used to assess functional outcomes. A comparison between mild and severe varus deformities was done using Student's t-test.

RESULTS

The mean age was 66.35 ± 9.21 years. There were 79 (96.34%) knees with a mean preoperative varus hip-knee-ankle angle (HKA) of 12.85° ± 6.03° (range = 177°-148°). Postoperative limb alignment was achieved in the range of HKA 174° to 180°, with mean HKA being 175.78° ± 1.35°. The VAS-P improved significantly from a mean of 7.87 ± 0.81 preoperatively to 1.96 ± 1.43 at 18 months. KOOS-JR improved from 41.22 ± 7.6 preoperatively to 88.44 ± 8.23 at 18 months. A total of 73 (89.02%) cases achieved the minimal clinically important difference (MCID) for VAS-P and 77 (93.9%) cases achieved the MCID for KOOS-JR in our study. Functional outcomes were comparable among the mild (<10°) and severe (>10°) varus deformity cases at 18 months follow-up (p-value > 0.05). There was a significant difference in bone resection from the medial tibial and medial distal femoral condyle (p-value < 0.05) with less bone resected in the severe varus group. The amount of bone resected from the lateral tibial, distal lateral femoral, and posterior femoral condyles was comparable among the two groups (p-value > 0.05). FA was more bone conserving even in severe varus-deformed knees when compared to mechanical alignment (MA).

CONCLUSION

The use of FA with robotic assistance to correct severe varus deformities in TKA showed a significant reduction in VAS-P scores and an improvement in KOOS-JR scores. The functional outcomes were comparable with TKA in mild varus deformities. FA helps in preserving bone from the lateral tibial condyle and distal femur.

Quantifying Patient Expectations for Total Knee Arthroplasty: Expectations for Improvement Are Greater Than Minimal Clinically Important Difference

BACKGROUND

Achieving a minimal clinically important difference (MCID) in patient-reported outcomes following total knee arthroplasty (TKA) is common, yet up to 20% patient dissatisfaction persists. Unmet expectations may explain post-TKA dissatisfaction. No prior studies have quantified patient expectations using the same patient-reported outcome metric as used for MCID to allow direct comparison.

METHODS

This was a prospective study of patients undergoing TKA with 5 fellowship-trained arthroplasty surgeons at one academic center. Baseline Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) and Pain Interference (PI) domains were assessed. Expected PROMIS scores were determined by asking patients to indicate the outcomes they were expecting at 12 months postoperatively. Predicted scores were generated from a predictive model validated in the Function and Outcomes Research for Comparative Effectiveness in Total Joint Replacement (FORCE-TJR) dataset. T-tests were used to compare baseline, expected, and predicted PROMIS scores. Expected scores were compared to PROMIS MCID values obtained from the literature. Regression models were used to identify patient characteristics associated with high expectations.

RESULTS

There were 93 patients included. Mean age was 67 years (range, 30 to 85) and 55% were women. Mean baseline PROMIS PF and PI was 34.4 ± 6.7 and 62.2 ± 6.4, respectively. Patients expected significant improvement for PF of 1.9 times the MCID (MCID = 11.3; mean expected improvement = 21.6, 95% confidence interval [CI] 19.6 to 23.5, P < .001) and for PI of 2.3 times the MCID (MCID = 8.9; mean expected improvement = 20.6, 95% CI 19.1-22.2, P < .001). Predicted scores were significantly lower than expected scores (mean difference = 9.5, 95% CI 7.7 to 11.3, P < .001). No unique patient characteristics were associated with high expectations (P > .05).

CONCLUSIONS

To our knowledge, this study is the first to quantify preoperative patient expectations using the same metric as MCID to allow for direct comparison. Patient expectations for improvement following TKA are ∼2× greater than MCID and are significantly greater than predicted outcome scores. This discrepancy challenges currently accepted standards of success after TKA and indicates a need for improved expectation setting prior to surgery.

Utilization of Blood Flow Restriction Therapy with a Former Triathlete After Total Knee Arthroplasty: A Case Report

Introduction and Purpose

Knee osteoarthritis (OA) is a common condition that limits function and reduces quality of life. Total knee arthroplasty (TKA) is a surgical procedure that replaces the joint surfaces to address anatomical changes due to knee OA. While TKA improves symptoms and function, postoperative impairments are common, including reduced quadriceps strength. Blood flow restriction (BFR) may be a viable option for patients following TKA, as it can improve strength with a minimal amount of joint loading compared to traditional strength training. The purpose of this case report is to describe the impact of BFR use in an individual after TKA, employing pain measurements, quantitative sensory testing, patient-reported outcome measures, physical performance tests, and muscle strength and power testing to explore potential treatment effects and identify potential predictors of response for future studies.

Case Description

A 49-year-old former female triathlete with a history of knee injury and arthroscopic surgery underwent a right TKA and sought physical therapy (PT) due to pain, limited range of motion (ROM), and knee instability during weight bearing activity. PT interventions included manual therapy, gait training, and a home program. Despite participating in supervised PT, she had persistent pain, ROM deficits, and muscle weakness 16 weeks following TKA. BFR was incorporated into her home program, 16-weeks postoperatively. The Short Form McGill Pain Questionnaire-2 (SF-MPQ-2) and Numeric Pain Rating Scale (NPRS) were used to measure pain. Quantitative sensory testing included pressure pain threshold (PPT) and two-point discrimination (TPD) to measure change in sensory perception. Patient-reported outcome measures to assess perceived physical function were the Knee injury and Osteoarthritis Outcome Score (KOOS) and the KOOS- Joint Replacement (KOOS-JR). Physical performance was measured through the 30-second fast walk test (30SFW), timed stair climb test (SCT), 30-second chair standing test (CST), and the timed up and go (TUG). Knee ROM was assessed through standard goniometry. Knee extensor and flexor muscle strength and power were measured with an instrumented dynamometer for isokinetic and isometric testing, generating a limb symmetry index (LSI).

Outcomes

Pain and quantitative sensory testing achieved clinically meaningful improvement suggesting reduced sensitivity during and after BFR utilization. Perceived physical function and symptoms significantly improved, particularly in sports and recreation activities, and were best captured in the KOOS, not the KOOS-JR. Physical performance reached clinically meaningful improvement in walking speed, chair stand repetitions, and timed stair climb tests after BFR. Isokinetic and isometric strength and power in knee extensors and flexors increased significantly after BFR compared to the uninvolved leg as determined by LSI.

Discussion

In this case, BFR appeared to be a safe and well-tolerated intervention. The results suggest potential benefits in terms of increased function, strength, power, and reduced pain in this specific person after TKA. Comprehensive pain and sensory assessments alongside clinical measures may help identify suitable patients for BFR after TKA. The KOOS-Sport & Recreation subscale may be more responsive to monitor functional recovery compared to the KOOS-JR, possibly due to the subject's athletic background.

Level of Evidence

4.

High Area Deprivation Index is Associated With Not Achieving the Patient-acceptable Symptom State After TKA

BACKGROUND

The Area Deprivation Index (ADI) approximates a patient's relative socioeconomic deprivation. The ADI has been associated with increased healthcare use after TKA, but it is unknown whether there is an association with patient-reported outcome measures (PROMs). Given that a high proportion of patients are dissatisfied with their results after TKA, and the large number of these procedures performed, knowledge of factors associated with PROMs may indicate opportunities to provide support to patients who might benefit from it.

QUESTIONS/PURPOSES

(1) Is the ADI associated with achieving the minimum clinically important difference (MCID) for the Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain, Joint Replacement (JR), and Physical Function (PS) short forms after TKA? (2) Is the ADI associated with achieving the patient-acceptable symptom state (PASS) thresholds for the KOOS pain, JR, and PS short forms?

METHODS

This was a retrospective study of data drawn from a longitudinally maintained database. Between January 2016 and July 2021, a total of 12,239 patients underwent unilateral TKA at a tertiary healthcare center. Of these, 92% (11,213) had available baseline PROM data and were potentially eligible. An additional 21% (2400) of patients were lost before the minimum study follow-up of 1 year or had incomplete data, leaving 79% (8813) for analysis here. The MCID is the smallest change in an outcome score that a patient is likely to perceive as a clinically important improvement, and the PASS refers to the threshold beyond which patients consider their symptoms acceptable and consistent with adequate functioning and well-being. MCIDs were calculated using a distribution-based method. Multivariable logistic regression models were created to investigate the association of ADI with 1-year PROMs while controlling for patient demographic variables. ADI was stratified into quintiles based on their distribution in our sample. Achievement of MCID and PASS thresholds was determined by the improvement between preoperative and 1-year PROMs.

RESULTS

After controlling for patient demographic factors, ADI was not associated with an inability to achieve the MCID for the KOOS pain, KOOS PS, or KOOS JR. A higher ADI was independently associated with an increased risk of inability to achieve the PASS for KOOS pain (for example, the odds ratio of those in the ADI category of 83 to 100 compared with those in the 1 to 32 category was 1.34 [95% confidence interval 1.13 to 1.58]) and KOOS JR (for example, the OR of those in the ADI category of 83 to 100 compared with those in the 1 the 32 category was 1.29 [95% CI 1.10 to 1.53]), but not KOOS PS (for example, the OR of those in the ADI category of 83 to 100 compared with those in the 1 the 32 category was 1.09 [95% CI 0.92 to 1.29]).

CONCLUSION

Our findings suggest that social and economic factors are associated with patients' perceptions of their overall pain and function after TKA, but such factors are not associated with patients' perceptions of their improvement in symptoms. Patients from areas with higher deprivation may be an at-risk population and could benefit from targeted interventions to improve their perception of their healthcare experience, such as through referrals to nonemergent medical transportation and supporting applications to local care coordination services before proceeding with TKA. Future research should investigate the mechanisms underlying why socioeconomic disadvantage is associated with inability to achieve the PASS, but not the MCID, after TKA.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Staged Bilateral Total Knee Arthroplasty: Differing Results Comparing the First and Second Knees

BACKGROUND

Patients often prefer one knee over the other following staged bilateral total knee arthroplasty (BTKA). Our study compared patient-reported outcomes scores of each knee following BTKA and identified factors that may contribute to the identified discrepancies.

METHODS

All patients who underwent staged BTKA between July 2014 and August 2022 were identified. The patient-reported outcomes were collected preoperatively and at 2 weeks, 6 weeks, 1 year, and 2 years postoperatively. Each knee's results were compared using paired t-tests and McNemar tests. Preoperative Kellgren-Lawrence Grade (KLG), postoperative range of motion (ROM), reoperation rates, and manipulations under anesthesia (MUAs) were collected. Results were stratified based on time between TKAs (< 3 months, 3 to 12 months, 1 to 2 years, and > 2 years).

RESULTS

There were 911 patients who underwent staged BTKA, with a mean 4.1-year follow-up. The ROM, patient satisfaction, MUAs, and reoperations were not significantly different between knees. Comparing the KLG of the first and second knees, 71% had the same KLG for both knees, 21% had a lower KLG, and 7% of the second knees had a higher KLG. The first knee had greater pain reduction (-10.6 at 2 weeks, -27.4 at 6 weeks) compared to the second (9.3 at 2 weeks, -8.1 at 6 weeks) (P < .0001) and better improvement in Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) score (8.5 at 2 weeks, 16.9 at 6 weeks) compared to the second (-5.8 at 2 weeks, 5.0 at 6 weeks) (P < .0001). The 1-year outcomes between first and second knees, or recovery curves, were not different when stratifying by time between TKAs.

CONCLUSIONS

The second knee in a staged BTKA has less delta improvement in KOOS JR and pain scores at early follow-up, likely due to higher starting KOOS JR and Patient-Reported Outcomes Measurement Information System scores, despite similar final patient satisfaction and clinical outcome measures. Lower KLG in the second total knee arthroplasty (TKA) may contribute to these findings. An MUA after the first TKA is highly predictive of an MUA after the second TKA.

Outcomes following open acetabular labrum reconstruction: Comparing fresh-frozen tendon with fresh meniscus allograft transplantation

Background

Symptomatic acetabular labral insufficiency in young, active patients is often treated with labral repair or reconstruction using fresh-frozen allografts. However, fresh-frozen tendon allografts do not have tissue or material properties that closely mimic acetabular labral fibrocartilage. Recent studies suggest meniscal allografts may be a better biomechanical, geometric, and material alternative for acetabular labrum reconstruction (ALR).

Hypothesis

Patients undergoing open ALR using fresh meniscus allograft transplants (MAT) will have better outcomes than those using fresh-frozen tendon allografts transplants (TAT) when comparing initial treatment success, diagnostic imaging assessments, and patient-reported pain and function scores.

Study design

Cohort Study.

Methods

With IRB approval, patients undergoing ALR with either TAT or MAT were included when initial (>1-year) outcomes data related to treatment success, pain, and function were available. In addition, a subcohort of patients underwent magnetic resonance imaging at least 6-months after surgery to evaluate allograft healing.

Results

Initial success rate, defined as no need for ALR revision or conversion to total hip arthroplasty (THA), was 88.9% for the entire group (n = 27, TAT = 5, MAT = 22) with 1 (20%) patient in the TAT cohort and 2 patients (9.9%) in the MAT cohort undergoing THA. In the MAT cohort, significant improvements were documented for physical function and pain scores at 1 year and final follow-up (FFU)(mean 26.8 months). Improvements in pain and function were noted at 1-year, but not at FFU (mean 59.6 months) in the TAT group. MRIs completed at least 6 months after labrum reconstruction showed improved allograft integrity and integration in the MAT cohort over the TAT cohort.

Conclusion

For acetabular labrum reconstructions, MAT was associated with a higher initial success rate, superior patient reported outcomes, and subjectively better MRI findings when compared to TAT.

Gluteal Tendinopathy Is Associated With Lower Patient-Reported Outcome Measures in Total Hip Arthroplasty With a Posterior Approach: A Prospective Cohort Study of 1,538 Patients

BACKGROUND

Gluteal tendinopathy (GT) is found in 20 to 25% of patients undergoing total hip arthroplasty (THA). Despite this, there is a scarcity of literature assessing the association between GT and THA outcomes. The aim of this study was to evaluate whether intraoperative diagnosis of GT negatively affected postoperative outcomes.

METHODS

Consecutive patients undergoing primary THA for osteoarthritis via a posterior approach over 5 years were recruited in a prospective study. Gluteal tendinopathy was assessed and graded at the time of surgery, but not repaired. A total of 1,538 (93%) completed the patient-reported outcome measures (PROMs) at 1 year after surgery and were included in the analysis. The PROMs included the Oxford Hip Score (OHS), Hip Disability and Osteoarthritis Outcome Score Joint Replacement (HOOS JR), and EuroQol 5-Dimension, and were collected preoperatively and one year after THA.

RESULTS

The gluteal tendons were graded as 4 distinct grades: normal (n = 1,023, 66%), tendinopathy but no tear (n = 337, 22%), partial thickness tear (n = 131, 9%), and full thickness tear (n = 47, 3%). The occurrence of GT was associated with age, body mass index, and sex. There was no significant difference in baseline OHS or HOOS JR scores according to GT grade. As GT grade increased, lower median 1-year OHS (P = .001) and HOOS JR (P = .016) were observed. This association was confirmed by linear regression analysis with 1-year OHS (B = 0.5, 95% CI = -0.9 to -0.1, P = .011) when controlled for age and sex.

CONCLUSIONS

Gluteal tendinopathy was commonly observed and was associated with inferior 1-year PROMs in patients undergoing THA via posterior approach. Increasing degree of tendinopathy was a negative prognostic factor for outcomes and patient satisfaction.

LEVEL OF EVIDENCE

Level 2 (High quality prospective cohort study).

Functional Articulating Antibiotic Spacers for Chronic Native Septic Knee Arthritis

Background

Semipermanent functional spacers are now utilized for prosthetic joint infection in an attempt to avoid another surgery with 2-stage treatment. This study evaluates the results of metal-on-polyethylene articulating spacers for the treatment of chronic native septic knee arthritis.

Methods

This is a retrospective review of 18 patients treated with metal-on-polyethylene articulating antibiotic spacers constructed with all-polyethylene tibial components or with polyethylene inserts (PIs) with Steinmann pins or screws for chronic native knee infection. Demographic information, spacer construct type, prior knee surgery, complications, infecting organisms, infection eradication, and functional results were analyzed.

Results

Of 18, 8 (44%) spacers were all-polyethylene tibial components and 10 (56%) were PI. Of 18 patients, 5 (28%) experienced spacer complications. Of 18 patients, 12 (67%) underwent a second reimplantation surgery (mean 106 days), while 6 (33%) retained their spacer (average duration 425 days). The PI group performed better in Knee Injury and Osteoarthritis Outcome score for Joint Replacement according to minimum clinically important difference and patient acceptable symptom state (PASS) criteria. The overall reimplantation group achieved Knee Injury and Osteoarthritis Outcome score for Joint Replacement PASS criteria and minimum clinically important difference criteria, while the maintained articulating spacer group did not achieve PASS criteria; however, they did reach minimum clinically important difference.

Conclusions

Functional articulating spacers are a viable treatment for chronic, native knee septic arthritis. The PI patient group had a greater improvement in Knee Injury and Osteoarthritis Outcome score for Joint Replacement scores and had no significant difference in reimplantation rate as the all-polyethylene tibial components patient group. Both planned 2-stage reimplantation and longer-term spacer retention show promising results for this difficult clinical problem.

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.