Validation of the Knee Injury and Osteoarthritis Outcome Score subscales for patients with articular cartilage lesions of the knee

Microfragmented adipose tissue injection reduced pain compared to a saline control among patients with symptomatic knee osteoarthritis during one-year follow-up: a randomized, controlled trial

PURPOSE

To evaluate the effectiveness of microfragmented adipose tissue (MFAT) for pain relief and improved joint functionality in knee OA in a randomized, controlled clinical trial with 1-year follow-up.

METHODS

Seventy-five patients were stratified by baseline pain level, and randomized to one of three treatment groups: MFAT, corticosteroid (CS), or saline control (C) injection. Patients 18 years of age or older, diagnosed with symptomatic knee osteoarthritis, with radiographic evidence of knee osteoarthritis and a visual analog pain scale (VAS) score of 3/10 or greater were included. Patients were excluded if they had any prior intra-articular knee injection, current knee ligamentous instability or an allergy to lidocaine/corticosteroid. The VAS pain scale, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Knee Injury and Osteoarthritis Outcome score (KOOS) were recorded pre-procedure and at 2 weeks, 6 weeks, 3 and 6 months, and 1 year follow-up.

RESULTS

MFAT demonstrated consistent and statistically significant improvements across all primary outcome measures for joint pain and functionality compared to C. For MFAT, there was a significant improvement over baseline at each follow-up, with median (95% CI) KOOS Pain score changes of 18.1 (11.1, 26.4) at week 2 to 27.8 (19.4, 37.5) at 1 year. For CS, the median KOOS pain score reached a maximum of 22.2 (15.3, 30.6) at week 2, only to level off to 13.9 (-2.8, 29.2), a level not statistically different from baseline, at 1 year. The median changes for C hovered around 6-11 points, with statistically significant improvements over baseline indicating a placebo effect. Similar trends were seen for the WOMAC Pain score and VAS Pain score.

CONCLUSIONS

In this study, MFAT demonstrated a clinically significant improvement in primary outcome scores compared with a saline control group, while the corticosteroid group only showed statistically significant improvement compared to the control group at 2 and 6 weeks. This finding indicates that MFAT may be a viable alternative treatment for patients with knee OA that fall into the orthopaedic treatment gap.

Factors Influencing Long-term Outcomes After Matrix-Induced Autologous Chondrocyte Implantation: Long-term Results at 10 Years

BACKGROUND

Matrix-induced autologous chondrocyte implantation (MACI), the third-generation of the technique, is an established procedure for the treatment of focal cartilage defects in the knee. However, the literature lacks long-term results of MACI with good statistical power.

PURPOSE

To determine long-term survival and patient-reported outcomes (PROs) in a representative cohort and to identify patient- and surgery-related parameters that may influence long-term clinical outcomes.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 103 patients were clinically evaluated at the current follow-up of 8.1 years (range, 5-11.9 years). PRO measures (PROMs) included the Knee injury and Osteoarthritis Outcome Score (KOOS), EQ-5D, visual analog scale for pain, and Tegner Activity Scale. Magnetic resonance imaging results were evaluated by using the AMADEUS (area measurement and depth and underlying structures) and MOCART (magnetic resonance observation of cartilage repair tissue) 2.0 knee score classification systems. Potential factors influencing PROs were first identified univariately and investigated in a multivariate regression model.

RESULTS

The defects had a mean size of 4.8 cm2 (range, 1.2-12 cm2) and were predominantly femorotibial (66%). The mean Kaplan-Meier survival rate of revision for any reason was 97.2% ± 1.6% at 10 years. In comparison to preoperative values, all PROMs were significantly improved at the current follow-up (P < .05). The MOCART 2.0 score peaked at 12 months (mean, 80.2 ± 15.3 months) and showed no significant change at 96 months (mean, 76.1 ± 19.5 months; P = .142). The linear multivariate regression model identified an association of body mass index (BMI), MOCART 2.0 score, and number of previous knee surgeries with KOOS (R2 = 0.41; f2 = 0.69). Further analysis of the individual determinants revealed an optimal BMI range of 20 to 29 for favorable PROs at 96 months. Significant correlations of MOCART subscores with the overall KOOS were found for graft surface and structure, bony reaction, and subchondral detectable changes. Only 30% of patients with 2 previous surgeries and 20% of patients with 3 previous surgeries achieved a Patient Acceptable Symptom State (χ2 = 10.93; P = .012).

CONCLUSION

The present study shows consistently good long-term clinical outcomes after MACI with a low revision rate and high patient satisfaction. BMI and number of previous knee surgeries may influence clinical outcomes and should be considered in patient selection and education. There is a correlation between graft structure, subchondral bone changes on magnetic resonance imaging, and long-term PROMs.

Autologous Chondrocyte Implantation Is Not Better Than Arthroscopic Debridement for the Treatment of Symptomatic Cartilage Lesions of the Knee: Two-Year Results From a Randomized-Controlled Trial

Purpose

To compare the functional and patient-reported outcome measures after autologous chondrocyte implantation (ACI) and arthroscopic debridement (AD) in symptomatic, isolated cartilage injuries larger than 2 cm2 in patients aged 18 to 50 years.

Methods

Twenty-eight patients were included and randomized to ACI (n = 15) or AD (n = 13) and followed for 2 years. The primary outcome was the change in the Knee injury and Osteoarthritis Outcome Score (KOOS) Quality of Life (QoL) subscale.

Results

The mean age at inclusion was 34.1 (standard deviation [SD] 8.5) years. There were 19 (68%) male patients. The mean size of the lesion was 4.2 (SD 1.7) cm2. There was a statistically significant and clinically meaningful improvement in patient-reported outcome measures from baseline to 2 years in both groups. The improvement from baseline to final follow-up for the primary endpoint (the KOOS QoL subscale) was larger for the AD group (39.8, SD 9.4) compared with the ACI group (23.8, SD 6.7), but this difference was not statistically significant (P = .17). However, according to a mixed linear model there were statistically significantly greater scores in the AD group for several KOOS subscales at several time points, including KOOS QoL, KOOS pain, and KOOS sport and recreation at 2 years.

Conclusions

This study indicates that AD followed by supervised physiotherapy is equal to or better than ACI followed by supervised physiotherapy in patients with isolated cartilage lesions of the knee larger than 2 cm2. The improvement in KOOS QoL score from baseline to 2 years was clinically meaningful for both groups (23.8 points for ACI and 39.8 points AD), and larger for the AD group by 16 points.

Level of Evidence

Level I, prospective randomized controlled trial.

Item-Specific Knee Injury and Osteoarthritis Outcome Score Characterization of Patients With Medial Meniscus Root Tear

Background

Most studies regarding medial meniscus posterior root tear (MMPRT) report total Knee injury and Osteoarthritis Outcome Score (KOOS) subscale values as important patient-reported outcomes, but there are few symptom-specific characterizations of patients with MMPRT.

Purpose/Hypothesis

The purpose of this study was to characterize the prevalence and severity of symptoms and functional limitations among patients with MMPRT based on item-level KOOS responses. It was hypothesized that patients with MMPRT would show similar symptoms to those of other meniscal tear types, with items from the KOOS pain subscale forming a majority of the most severe and prevalent symptoms.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

The records of 1466 patients with medial meniscus root tear between January 2017 and December 2021 at a single institution were reviewed. KOOS subscale scores and item-specific responses from initial evaluation were collected for each patient. Each KOOS item was scored on a scale from 1 (none/least severe) to 5 (extreme/most severe). Median and mean item-level responses were calculated and ranked in order of most to least severe. For statistical analysis, item-level prevalence rates were calculated as the proportion of patients reporting at least mild symptoms and ranked from most to least prevalent.

Results

Included were 61 patients with MMPRT verified on magnetic resonance imaging (MRI). The most severe items according to item-level KOOS response were as follows: awareness of knee problem (mean, 4.62 [95% CI, 4.47-4.78]), difficulty jumping (mean, 4.06 [95% CI, 3.73-4.39]), difficulty twisting or pivoting (mean, 4.04 [95% CI, 3.76-4.32]), difficulty kneeling (mean, 3.98 [95% CI, 3.65-4.31]), and modification of lifestyle (mean, 3.94 [95% CI, 3.69-4.20]). The most prevalent items were knee stiffness later in the day, pain going up- or downstairs, difficulty ascending stairs, difficulty getting in and out of the car, difficulty twisting or pivoting, awareness of knee problem, and modification of lifestyle, with all patients reporting at least mild symptoms for each. Of the 11 most severe and prevalent symptoms, 8 came from the KOOS-Pain item-specific responses.

Conclusion

Pain-related items made up a majority of the most severe and most prevalent symptoms as identified by the item-specific KOOS responses. However, meniscal symptoms commonly seen in other tear types, such as clicking and knee stiffness, were still quite prevalent in patients with MMPRT.

The role of autologous bone grafting in matrix-associated autologous chondrocyte implantation at the knee: Results from the German Cartilage Registry (KnorpelRegister DGOU)

PURPOSE

To investigate whether concomitant autologous bone grafting adversely affects clinical outcome and graft survival after matrix-associated autologous chondrocyte implantation (M-ACI).

METHODS

The present study examines registry data of patients who underwent M-ACI with or without autologous bone grafting for large-sized chondral or osteochondral defects. Propensity score matching was performed to exclude potential confounders. A total of 215 patients with similar baseline characteristics were identified. Clinical outcome was assessed at the time of surgery and at 6, 12, 24, 36 and 60 months using the Knee Injury and Osteoarthritis Outcome Score (KOOS). KOOS change, clinical response rate, KOOS subcomponents and failure rate were determined.

RESULTS

Patients treated with M-ACI and autologous bone grafting achieved comparable clinical outcomes compared with M-ACI alone. At 24 months postoperatively, the patient-reported outcome (PRO) of patients treated with M-ACI and autologous bone grafting was even significantly better as measured by KOOS (74.9 ± 18.8 vs. 79.2 ± 15.4; p = 0.043). However, the difference did not exceed the minimal clinically important difference (MCID). In patients with M-ACI and autologous bone grafting, a greater change in KOOS relative to baseline was observed at 6 (9.3 ± 14.7 vs. 15.0 ± 14.7; p = 0.004) and 12 months (12.6 ± 17.2 vs. 17.7 ± 14.6; p = 0.035). Overall, a high clinical response rate was observed in both groups at 24 months (75.8% vs. 82.0%; p = n.s.). The estimated survival at the endpoint of reoperation for any reason was 82.1% (SD 2.8) at 8.4 years for isolated M-ACI and 88.7% (SD 2.4) at 8.2 years for M-ACI with autologous bone grafting (p = 0.039).

CONCLUSIONS

Even in the challenging cohort of large osteochondral defects, the additional treatment with autologous bone grafting leads to remarkably good clinical outcomes in patients treated with M-ACI. In fact, they tend to benefit more from surgery, have lower revision rates and achieve clinical response rates earlier. Subchondral bone management is critical to the success of M-ACI and should be addressed in the treatment of borderline defects.

LEVEL OF EVIDENCE

Level III.

Previous cartilage surgery is associated with inferior patient-reported outcomes after knee arthroplasty

PURPOSE

The hypothesis of the present study assumed that a history of focal cartilage lesions would not affect Knee Injury and Osteoarthritis Outcome scores (KOOSs) following knee arthroplasty compared to a matched national cohort of knee arthroplasty patients.

METHODS

Fifty-eight knee arthroplasty patients with previous surgery for focal cartilage lesions (cartilage cohort) were compared to a matched cohort of 116 knee arthroplasty patients from the Norwegian Arthroplasty Register (control group). Age, sex, primary or revision arthroplasty, type of arthroplasty (total, unicondylar or patellofemoral), year of arthroplasty surgery and arthroplasty brand were used as matching criteria. Demographic data and KOOS were obtained through questionnaires. Regression models were employed to adjust for confounding factors.

RESULTS

Mean follow-up post knee arthroplasty surgery was 7.6 years (range 1.2-20.3) in the cartilage cohort and 8.1 (range 1.0-20.9) in the control group. The responding patients were at the time of surgery 54.3 versus 59.0 years in the cartilage and control group, respectively. At follow-up the control group demonstrated higher adjusted Knee Injury and Osteoarthritis Outcome subscores than the previous focal cartilage patients with a mean adjusted difference (95% confidence interval in parentheses): Symptoms 8.4 (0.3, 16.4), Pain 11.8 (2.2, 21.4), Activities of daily living (ADL) 9.3 (-1.2, 18.6), Sport and recreation 8.9 (-1.6, 19.4) and Quality of Life (QoL) 10.6 (0.2, 21.1). The control group also demonstrated higher odds of reaching the patient-acceptable symptom state threshold for the Knee Injury and Osteoarthritis Outcome subscores with odds ratio: Symptoms 2.7 (1.2, 6.4), Pain 3.0 (1.3, 7.0), ADL 2.1 (0.9, 4.6) and QoL 2.4 (1.0, 5.5).

CONCLUSION

Previous cartilage surgery was associated with inferior patient-reported outcomes after knee arthroplasty. These patients also exhibited significantly lower odds of reaching the patient-acceptable symptom state threshold for the Knee Injury and Osteoarthritis Outcome subscores.

LEVEL OF EVIDENCE

Level III.

The AMADEUS score is not a sufficient predictor for functional outcome after autologous chondrocyte implantation (ACI) of the knee: data from the German Cartilage Registry (KnorpelRegister DGOU)

INTRODUCTION

The AMADEUS (Area Measurement And DEpth and Underlying Structures) score has advanced to a commonly used tool for MRI-based chondral defect severity grading prior to cartilage knee surgery. It was the intention of this study to assess the AMADEUS for a potential correlation with clinical data by patient-reported outcome measures (PROMs).

METHODS

A total of 51 patients undergoing ACI (autologous chondrocyte implantation) between 2016 and 2022 were found eligible and retrospectively analyzed. All patients were registered in the German Cartilage Registry prior to surgery and follow-up data were collected using the Knee Osteoarthritis Outcome score (KOOS), the International Knee Documentation Committee (IKDC) Form and the numeric rating scale (NRS). Pre-operative MRI images were scored by three raters using the AMADEUS classification system, and an overall AMADEUS score was calculated which was subsequently correlated with pre- and post-operative PROMs.

RESULTS

Mean patient age was 32.67 ± 8.37 years and mean defect size area 343.04 mm2 ± 139.45 mm2. No correlative capacity of the pre- and postoperative IKDC, KOOS or NRS scores was found with the AMADEUS final score or any of its subscores. From the pre- to postoperative visit, a significant improvement of the PROMs (IKDC: 45.53 ± 21.00 vs. 59.83 ± 17.93, p = 0.04; KOOS Pain: 58.00 ± 16.70 vs. 76.06 ± 19.20, p = 0.03; KOOS ADL: 64.17 ± 18.76 vs. 82.11 ± 16.68, p < 0.01; KOOS Sports: 26.11 ± 18.52 vs. 50.56 ± 23.94, p = 0.01; KOOS QOL: 25.50 ± 14.26 ± 45.28 ± 19.03, p = 0.00) was found. Intraclass correlation coefficients showed an overall good interrater agreement for the AMADEUS total score (ICC = 0.75).

CONCLUSIONS

Study results suggest no correlative capacity of the AMADEUS with routinely used PROMs in patients undergoing ACI. Therefore, radiographically assessed cartilage defect characteristics poorly translate to pre- and postoperative patient-reported outcome data.

A systematic review demonstrating correlation of MRI compositional parameters with clinical outcomes following articular cartilage repair interventions in the knee

OBJECTIVE

Compositional-MRI parameters enable the assessment of cartilage ultrastructure. Correlation of these parameters with clinical outcomes is unclear. This systematic review investigated the correlation of various compositional- MRI parameters with clinical outcome measures following cartilage repair or regeneration interventions in the knee.

DESIGN

This study was registered with PROSPERO and reported in accordance with PRISMA. PubMed, Institute of Science Index, Scopus, Cochrane Central Register of Controlled Trials, and Embase databases were searched. All studies, regardless of type, that presented correlation of compositional- MRI parameters with clinical outcome measures were included. Two researchers independently performed data extraction and QUADAS-2 analysis. Compositional-MRI parameter change following intervention and correlation with clinical outcome measures were evaluated.

RESULTS

19 studies were included. Risk of bias was generally low. 5 different compositional parameters were observed from the included studies. However, due to the significant variability in the reporting of compositional-MRI parameters across studies, meta-analyses were possible only for T2 values and T2 index values (T2 value of repair cartilage relative to normal cartilage). Correlation of T2 values of repair cartilage with clinical outcome score was r ​= ​0.33 [0.15, 0.52]. Correlation of T2 index with clinical outcome score was r ​= ​0.52 [0.32, 0.77].

CONCLUSIONS

Correlation between T2 values and clinical outcome scores following knee cartilage repair were found. The heterogeneity of the correlations extracted from the included studies limited the scope for the meta-analysis. Thus, standardised, high-quality studies are required for better assessment of correlation between compositional MRI parameters and clinical outcome measures after cartilage repair.

REGISTRATION NUMBER

PROSPERO CRD42021287364.Study protocol available on PROSPERO website.

The simplified Chinese version of the Knee Injury and Osteoarthritis Outcomes Score (KOOS) in individuals with knee osteoarthritis for mainland China: the study of reliability and validity

BACKGROUND

The Knee Injury and Osteoarthritis Outcomes Score (KOOS) is a free clinical tool commonly used to evaluate the symptoms and functional status of patients with knee injury. For people who speak Chinese, the Hong Kong Chinese and Singapore Chinese versions are preferred. However, variations in the Chinese language and culture are influenced by the country's geography. KOOS for Mainland China has not been reported. Therefore, the current study was to cross-culturally translate the original English version into a simplified Chinese version and to investigate its psychometric properties.

METHODS

The simplified Chinese KOOS was obtained through forward-backward translation according to appropriate guidelines. A total of 158 individuals with knee osteoarthritis (KOA) were recruited from 13 hospitals in China to examine the psychometric properties. The test-retest questionnaire was performed at an interval of 5-7 days. Test-retest reliability and internal consistency were evaluated using the intraclass correlation coefficient (ICC) and Cronbach's alpha, respectively. The data of the first test were used to analyse the construct validity of the simplified Chinese KOOS and Chinese SF-36 through convergent and discriminant validity using Spearman's correlation coefficient.

RESULTS

Cross-cultural translation exhibited minor cultural differences, and the questionnaire was well understood by the patients. The data from 128 patients, used for the test-retest reliability study, showed good to excellent reliability, with an ICC of 0.808-0.976 for all KOOS subscales. The Cronbach's alpha for all subscales ranged from 0.757 to 0.970, indicating acceptable internal consistency. There was a low-to-high correlation between the five domains of the simplified Chinese version of the KOOS and all domains of the SF-36 in construct validity.

CONCLUSION

The simplified Chinese KOOS demonstrated acceptable reliability and validity. In clinical practice and research, this version can help provide valuable information on health-related quality of life for Chinese individuals with KOA in mainland China.

Four cases report: Treatment of knee joint cartilage defects using autologous chondrocyte patch implantation

INTRODUCTION

Autologous chondrocyte implantation (ACI) is a crucial method for the treatment of defects in articular cartilage. However, the extant methods for the preparation of autologous chondrocyte patch are relatively complicated and money-consuming. Therefore, an efficient, reliable, easy-to-follow, and cost-effective technique is needed to overcome constraints. This case report aims to introduce an autologous chondrocyte patch fabrication technique to repair knee joint cartilage defects and report our typical cases with a 2-year follow-up.

CASE PRESENTATION

We described four cases in which patients complained of knee joint pain. According to radiological examination, the patients were diagnosed as knee joint cartilage defect. Arthroscopy and autologous chondrocyte patch implantation were performed as well as a 2-year follow up of patients. The autologous chondrocyte patch for knee joint cartilage repair was fabricated using a "sandwich" technique. The preoperative and postoperative knee function was evaluated by four subjective evaluation systems. MRI was performed for all patients to achieve more intuitionistic observation of the postoperative radiological changes of defect sites. The quality of repaired tissue was evaluated by Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART). Postoperative follow-up showed improvement in clinical and MOCART scores for all patients. However, one patient complained of knee joint pain after walking for a long time or recreational activities from 12- to 18-month postoperatively. The location of pain for this patient was not in accordance with the location of cartilage defect.

CONCLUSION

The patients undergoing autologous chondrocyte patch implantation demonstrated clinical improvement and good quality of repaired tissue postoperatively. The procedure is an efficient and cost-effective treatment for knee joint cartilage defect in this report. In addition, patients with osteoarthritis carry the risk of a poor outcome after the procedure, and whether to have a procedure should be considered carefully.

Four of five frequently used orthopedic PROMs possess inadequate content validity: a COSMIN evaluation of the mHHS, HAGOS, IKDC-SKF, KOOS and KNEES-ACL

PURPOSE

Content validity is the most important property of PROMs. The COSMIN initiative has published guidelines for evaluating the content validity of PROMs, but they have only sparsely been applied to relevant PROMs for musculoskeletal conditions. The aim of this study was to use the COSMIN Risk of Bias checklist to evaluate the content validity of five PROMs, that are highly relevant in musculoskeletal research and used by the arthroscopic surgery community: the modified Harris' Hip Score (mHHS), the Copenhagen Hip and Groin Outcome Score (HAGOS), the International Knee Documentation Committee Subjective Knee evaluation Form (IKDC-SKF), the Knee injury and Osteoarthritis Outcome Score (KOOS) and the Knee Numeric-Entity Evaluation Score ACL (KNEES-ACL).

METHODS

The development articles for the five PROMs were identified through searches in PubMed and SCOPUS. A literature search was performed to identify additional studies assessing content validity of the PROMs. Additional information, necessary for the assessments, was obtained from the PROM developers after direct request. To evaluate the quality of the development studies and rate the content validity, the COSMIN Risk of Bias checklist was applied to all studies.

RESULTS

All five development studies were identified. Three subsequent content validity studies were identified, all evaluating KOOS and one also IKDC. One content validity study was of inadequate quality and excluded from further analysis. The development of mHHS, IKDC-SKF, and KOOS was rated inadequate and possess insufficient content validity for their target populations. Due to the irrelevance of multiple items, KOOS was in particular inappropriate to evaluate patients with an ACL injury. The development of HAGOS was also rated inadequate, although the insufficiency aspects can be regarded as minor. KNEES-ACL possessed sufficient content validity.

CONCLUSION

Out of five PROMs, only KNEES-ACL possessed sufficient content validity. Particularly, KOOS should not be used as an outcome for patients with an ACL injury. There is an urgent need for condition-specific PROMs for musculoskeletal conditions, developed with adequate methods.

LEVEL OF EVIDENCE

III.

Establishing Clinically Significant Outcomes After Anterior Cruciate Ligament Reconstruction in Pediatric Patients

PURPOSE

The purpose of this study was to establish clinically significant outcome values for the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) after anterior cruciate ligament reconstruction (ACLR) in the pediatric and adolescent populations and to assess factors that were associated with achieving these outcomes.

METHODS

Patients between the age of 10 to 21 who underwent ACLR between 2016 and 2018 were identified and patient-reported outcomes (PROs) were collected preoperatively and postoperatively. Intraoperative variables collected included graft choice, graft size (diameter), graft fixation method, and concomitant procedures. PROs collected for analysis were the International Knee Documentation Committee Score (IKDC) and Knee Injury and Osteoarthritis Outcome Score (KOOS). MCID and PASS were calculated using receiver operating characteristic with area under the curve analyses for delta (ie, baseline-to-postoperative change) and absolute postoperative PRO scores, respectively.

RESULTS

A total of 59 patients were included in the analysis. Of the entire study population, 53 (89.8%) reported satisfaction with their surgical outcome. The established MCID threshold values based on the study population were 33.3 for IKDC, 28.6 for (KOOS) Symptoms, 19.4 for Pain, 2.9 for activities of daily living (ADL), 45.0 for Sport, and 25.0 for Quality of Life (QoL). Postoperative scores greater than the following values corresponded to the PASS: 80.5 for IKDC, 75.0 (KOOS) Symptoms, 88.9 for Pain, 98.5 for ADL, 75.0 for Sport, and 68.8 for QoL.

CONCLUSION

Clinically meaningful outcomes including MCID and PASS were established for pediatric ACLR surgery using selected PRO measures, IKDC, and KOOS. Patient age, sex, graft type, and graft size were not associated with greater achievement of these outcomes. In contrast, collision sports, fixed-object high-impact rotational landing sports, and concomitant meniscectomy surgery were associated with a decreased likelihood of achieving clinically significant improvement. However, findings must be interpreted with caution due to limitations in follow-up and sample size.

LEVEL OF EVIDENCE

Level IV: case series.

The subjective knee value is a valid single-item survey to assess knee function in common knee disorders

INTRODUCTION

The patient's perspective plays a key role in judging the effect of knee disorders on physical function. We have introduced the Subjective Knee Value (SKV) to simplify the evaluation of individual's knee function by providing one simple question. The purpose of this prospective study was to validate the SKV with accepted multiple-item knee surveys across patients with orthopaedic knee disorders.

MATERIALS AND METHODS

Between January through March 2020, consecutive patients (n = 160; mean age 51 ± 18 years, range from 18 to 85 years, 54% women) attending the outpatient clinic for knee complaints caused by osteoarthritis (n = 69), meniscal lesion (n = 45), tear of the anterior cruciate ligament (n = 23) and focal chondral defect (n = 23) were invited to complete a knee-specific survey including the SKV along with the Knee Injury Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee subjective knee form (IKDC-S). The Pearson correlation coefficient was used to evaluate external validity between the SKV and each patient-reported outcome measure (PROM) separately. Furthermore, patient's compliance was assessed by comparing responding rates.

RESULTS

Overall, the SKV highly correlated with both the KOOS (R = 0.758, p < 0.05) and the IKDC-S (R = 0.802, p < 0.05). This was also demonstrated across all investigated diagnosis- and demographic-specific (gender, age) subgroups (range 0.509-0.936). No relevant floor/ceiling effects were noticed. The responding rate for the SKV (96%) was significantly higher when compared with those for the KOOS (81%) and the IKDC-S (83%) (p < 0.05).

CONCLUSION

At baseline, the SKV exhibits acceptable validity across all investigated knee-specific PROMs in a broad patient population with a wide array of knee disorders. The simplified survey format without compromising the precision to evaluate individual's knee function justifies implementation in daily clinical practice.

LEVEL OF EVIDENCE

II, cohort study (diagnosis).

Concomitant full-thickness cartilage lesions do not affect patient-reported outcomes at minimum 10-year follow-up after ACL reconstruction

PURPOSE

To compare patients with a concomitant full-thickness cartilage lesion and anterior cruciate ligament (ACL) injury to patients with an isolated ACL injury at 10-15 years post ACL reconstruction.

METHODS

This is a longitudinal follow-up of a cohort of 89 patients that were identified in the Norwegian National Knee Ligament Registry and included in the index study in 2007. The study group consisted of 30 patients that underwent ACL reconstruction and had a concomitant, isolated full-thickness cartilage lesion (International Cartilage Repair Society [ICRS] grade 3-4). Each study patient was matched with two control patients who underwent ACL reconstruction but had no cartilage lesions (ICRS grade 1-4) (n = 59). At a median follow-up of 10.2 years (range 9.9-15.6), 65 patients (74%) completed the Knee Injury and Osteoarthritis Outcome Score (KOOS), which was the main outcome measure, resulting in 23 pairs after matching.

RESULTS

At a follow-up of 10-15 years after ACL reconstruction, no significant differences in KOOS were found between patients with a concomitant full-thickness cartilage lesion and patients without cartilage lesions. There was also no significant difference between the two groups when comparing the change over time in KOOS scores from preoperative to follow-up. Both groups showed significant improvement in all KOOS subscales from preoperative to follow-up, except for in the Symptoms subscale for the control group. The greatest improvement was in the QoL subscale for the study group.

CONCLUSION

ACL-reconstructed patients with a full-thickness cartilage lesion did not report worse outcomes at 10-15 years after surgery compared with patients with an isolated ACL injury. Our findings support that there is no long-term negative effect of a concomitant cartilage lesion in an ACL-reconstructed knee. These findings should be considered when discussing treatment and informing about the expected long-term outcome after ACL reconstruction to patients with such combined injuries.

LEVEL OF EVIDENCE

II.

Matrix-Associated Autologous Chondrocyte Implantation with Spheroid Technology Is Superior to Arthroscopic Microfracture at 36 Months Regarding Activities of Daily Living and Sporting Activities after Treatment

OBJECTIVE

Matrix-associated autologous chondrocyte implantation (ACI) and microfracture (MF) are well-established treatments for cartilage defects of the knee. However, high-level evidence comparing microfracture and spheroid technology ACI is limited.

DESIGN

Prospective, phase III clinical trial with patients randomized to ACI (N = 52) or MF (N = 50). Level of evidence: 1, randomized controlled trial. Both procedures followed standard protocols. For ACI 10 to 70 spheroids/cm² were administered. Primary outcome measure was the Knee Injury and Osteoarthritis Outcome Score (KOOS). This report presents results for 36 months after treatment.

RESULTS

Both ACI and MF showed significant improvement over the entire 3-year observation period. For the overall KOOS, noninferiority of ACI (the intended primary goal of the study) was formally confirmed; additionally, for the subscores "Activities of Daily Living" and "Sport and Recreation," superiority of ACI over MF was shown at descriptive level. Occurrence of adverse events were not different between both treatments (ACI 77%; MF 74%). Four patients in the MF group required reoperation which was defined as treatment failure. No treatment failure was reported for the ACI group.

CONCLUSIONS

Patients treated with matrix-associated ACI with spheroid technology showed substantial improvement in various clinical outcomes after 36 months. The advantages of ACI compared with microfracture was underlined by demonstrating noninferiority, in overall KOOS and superiority in the KOOS subscores "Activities of Daily Living" and "Sport and Recreation." In the present study, subgroups comparing different age groups and defect sizes showed comparable clinical outcomes.

The use of manual lymphatic drainage on clinical presentation of musculoskeletal injuries: A systematic review

The aim of this study was to provide a systematic review on the applicability of manual lymphatic drainage (MLD) in improving edema and clinical presentation postmusculoskeletal injuries. A review of the literature was performed in CINAHL, MANTIS, Medline, SPORTDiscus and Google Scholar, yielding a total of 8 articles. Half of the studies showed a strong quality assessment. Results from our work support the use of MLD for reducing edema reduction and pain as well as enhancing range of motion and patients' quality of life and satisfaction. Further research is needed to apply these findings to a broader range of musculoskeletal injuries and conditions.

Measuring Outcomes in Knee Articular Cartilage Pathology

Measuring outcomes following treatment of knee articular cartilage lesions is crucial to determine the natural history of disease and the efficacy of treatments. Outcome assessments for articular cartilage treatments can be clinical (based on failure, lack of healing, reoperation, need for arthroplasty), radiographic (X-ray, MRI), histologic, or patient reported and functional. The purpose of this review is to discuss the application and properties of patient-reported outcomes (PROs) with a focus on articular cartilage injuries and surgery in the knee. The most frequently used and validated PROs for knee articular cartilage studies include: the Knee injury and Osteoarthritis and Outcome Score, International Knee Documentation Committee Subjective Knee Form, and Lysholm score as knee-specific measures; the Marx Activity Rating Scale and Tegner Activity Scale as activity measures; and EQ-5D and SF-36/12 as generic quality-of-life measures. Incorporating these validated PROs in studies pertaining to knee articular cartilage lesions will allow researchers to fully capture clinically relevant outcomes that are most important to patients.

The Minimal Clinically Important Difference and Substantial Clinical Benefit in the Patient-Reported Outcome Measures of Patients Undergoing Osteochondral Allograft Transplantation in the Knee

OBJECTIVE

Little is known regarding the minimal clinically important difference (MCID) and substantial clinical benefit (SCB) with regard to the Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Lysholm score, and Short Form 12 (SF-12) score of patients who undergo osteochondral allograft transplantation (OCA). We aimed to determine the MCID and SCB associated with those patient-reported outcome measures (PROMs) after OCA.

DESIGN

We analyzed the data of 86 consecutive patients who underwent OCA and who completed satisfaction surveys at a minimum of 1 year postoperatively and had at least one repeated PROM. MCID was determined using an anchor-based method: the optimal cutoff point for receiver operative characteristic (ROC) curves. If an anchor-based method was inapplicable, distribution-based methods were employed. SCB was determined using ROC curve analysis.

RESULTS

Based on the ROC curve analysis, MCID was 16.7 for KOOS pain, 25 for KOOS sports/recreation, and 9.8 for IKDC. SCB was 27.7 for KOOS pain, 10.7 for KOOS symptom, 30 for KOOS sports/recreation, 31.3 for KOOS quality of life, 26.9 for IKDC, 25 for Lysholm, and 12.1 for SF-12 physical component summary. No significant association was noted between SCB achievement and the baseline patient factors and baseline PROMs.

CONCLUSION

We demonstrated the MCIDs and SCBs of several PROMs in patients undergoing OCA. These results will aid the interpretation of the effect of treatment and clinical trial settings. Moreover, the SCBs will help surgeons in the counseling of patients, where patients expect optimal results rather than minimal improvement.

High kinesiophobia and pain catastrophizing in people with articular cartilage defects in the knee and associations with knee function

PURPOSE

The purpose of this study was to evaluate the extent to which individuals with knee articular cartilage defects (ACDs) have kinesiophobia and pain catastrophizing, and how these psychological factors relate to self-reported knee outcomes.

METHODS

Thirty-five individuals seeking surgical consultation for an ACD in the knee confirmed with 3.0T MRI and 18 controls without history of knee injury participated in the study. Kinesiophobia was measured with the Tampa Scale of Kinesiophobia (TSK), and scored using the modified 11-item (TSK-11) methods. Pain catastrophizing was measured with the Pain Catastrophizing Scale (PCS). Data were analyzed using descriptive statistics, independent t-tests, chi-squared tests and Spearman's correlation coefficients, as appropriate (α = 0.05).

RESULTS

Participants with ACDs reported higher TSK-11 scores (median 27 [IQR 25-29]) and higher PCS scores (median 10 [IQR 4-18]) than controls (median TSK-11 16 [IQR 14-17], p < 0.001; median PCS 0 [IQR 0-9], p < 0.001). Within those with knee ACDs, higher TSK-11 scores were associated with worse knee pain, function on activities of daily living, sports/recreation, and knee-related quality of life scores (rho = -0.38 to -0.61). Higher pain catastrophizing was associated with worse function with activities of daily living and knee-related quality of life (rho = -0.37 to -0.40).

CONCLUSIONS

Kinesiophobia and pain catastrophizing in people with knee ACDs were higher than controls. Higher kinesiophobia and pain catastrophizing were associated with worse function and quality of life. Further study of the impact of these psychological factors on outcomes and prognosis in people with knee ACDs is warranted.

Minimal Clinically Important Differences and Substantial Clinical Benefit in Patient-Reported Outcome Measures after Autologous Chondrocyte Implantation

OBJECTIVE

We sought to determine the minimal clinically important difference (MCID) and substantial clinical benefit (SCB) associated with the Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Lysholm, and Short Form-12 (SF-12) after autologous chondrocyte implantation (ACI).

DESIGN

Ninety-two patients with satisfaction surveys at a minimum of 2 years postoperatively and at least 1 repeated patient-reported outcome measure (PROM) were analysed. The MCID was determined using 4 anchor-based methods: average change, mean change, minimally detectable change, and the optimal cutoff point for receiver operating characteristic (ROC) curves. If an anchor-based method was not applicable, standard deviation-based and effect size-based estimates were used. SCB was determined using ROC curve analysis.

RESULTS

The 4 anchor-based methods provided a range of MCID values for each PROM (11-18.8 for the KOOS pain, 9.2-17.3 for the KOOS activities of daily living, 12.5-18.6 for the KOOS sport/recreation, 12.8-19.6 for the KOOS quality of life, 10.8-16.4 for the IKDC, and 6.2-8.2 for the SF-12 physical component summary). Using the 2 distribution-based methods, the following MCID value ranges were obtained: KOOS symptom, 3.6 to 8.4; the Lysholm, 4.2 to 10.5; and the SF-12 mental component summary, 1.9 to 4.6. SCB was 30 for the KOOS sport/recreation and 34.4 for the IKDC, which most accurately predict substantial improvement. No significant association was noted between SCB achievement and the baseline PROMs.

CONCLUSION

The MCID and SCB determined in our study will allow interpretation of the effects of treatment in clinical practice and trials. Given the varied MCID values in this study, standardisation of the most appropriate calculation methods is warranted.

The effectiveness of Kinesio Taping® for mobility and functioning improvement in knee osteoarthritis: a randomized, double-blind, controlled trial

OBJECTIVE

To evaluate the effectiveness of the Kinesio Taping® method for mobility and functioning improvement for patients with knee osteoarthritis (KO).

DESIGN

Randomized, double-blinded, controlled trial.

SETTING

Outpatient rehabilitation department.

SUBJECTS

A total of 187 subjects with symptomatic I-III grade KO participated; of these, 157 subjects were included in the analyses (intervention group, n = 81 (123 knees); control group, n = 76 (114 knees).

INTERVENTION

The intervention group received a specific Kinesio Taping application, and the control group received non-specific knee taping for a month.

MAIN MEASURES

Changes in Knee injury and Osteoarthritis Outcome Scores (KOOS), knee active range of motion, 10-Meter Walk, and the five times sit to stand tests (5xSST) were assessed at baseline, after four weeks of taping, and a month post taping intervention. Subjective participants' experiences and opinions on the effect of knee taping were evaluated. The chosen level of significance was p < 0.05.

RESULTS

The mean age of participants was 68.7 ± 9.9 in intervention group and 70.6 ± 8.3 in control group (p > 0.05). The change from baseline in gait speed in the intervention group after taping month was +0.04 ± 0.1 m/s, at follow-up +0.06 ± 0.1 m/s; in control group +0.07 ± 0.1 m/s, and +0.09 ± 0.1 m/s; the change in time needed to accomplish 5xSST was -2.2 ± 3.2 seconds, at follow-up -2.4 ± 3.1 seconds; in control group -2.8 ± 3.6 seconds, and -2.4 ± 4 seconds. Improved knee flexion and enhancement in functioning assessed by KOOS were noticed in both groups, with lasting improvement to follow up. No difference in the change in the above-mentioned outcomes was found between groups (p > 0.05). Fewer subjects (6.2% (5) vs. 21.1% (16), χ2 = 7.5, df = 2, p = 0.024) from Kinesio Taping group were unsure if taping alleviated their mobility and more intervention group patients indicated higher subjective satisfaction with the effect of knee taping to symptom and mobility alleviation than control group (p < 0.005).

CONCLUSION

Investigated Kinesio Taping technique did not produce better results in mobility and functioning improvement over non-specific knee taping; however, it had higher patient-reported subjective value for symptom attenuation and experienced mobility enhancement.

[Effects of knee pain on postural control excluding the musculature of the craniomandibular system]

BACKGROUND

Knee pain can influence postural control in addition to changes in the anatomical structure of the knee joints.

OBJECTIVE

Because the influence of imbalances in the craniomandibular system has been proven multiple times, it is the aim of the present work to investigate the influence of various knee diagnoses on postural control excluding occlusal information by means of symmetrical packing using cotton rolls.

MATERIALS AND METHODS

One hundred and fifteen patients (74 male/41 female) aged 18-75 years with an average BMI of 25.13 ± 3.66 kg/m² took part in the study, among them 34 patients (26 male/8 female) with cruciate ligament injury, 26 (16 male/10 female) with meniscal lesions, 24 (13 male/11 female) with arthrosis, 21 (11 male/10 female) with patellar pain, and 10 (8 male/2 female) with other painful knee complaints. Postural control was increased using a force platform, the degree of severity of the disorder was recorded using the "Knee Injury and Osteoarthritis Outcome" questionnaire, and the occlusion packed on both sides with cotton rolls in the premolar area.

RESULTS

With increasing age, patients with knee arthrosis are more likely to stand on the hindfoot. In those with patellar disorder, increased weight-bearing on the forefoot correlates with increasing BMI. An increase in weight-bearing on the forefoot on the side of the uninjured knee in people with patellar disorder results not only in a reduction in quality of life but also level of daily activity.

DISCUSSION

The percentage weight-bearing on the zones of the feet differs in unilateral knee injuries (in particular, comparison of the side with the knee injury and the uninjured side). Age, BMI or gender are influencing factors. Because various correlations and/or effects in the subgroups of knee injuries are generated, an injury-specific analysis should be carried out. These effects are also identifiable in the subjective assessment of quality of life.

Safety and efficacy of matrix-associated autologous chondrocyte implantation with spheroid technology is independent of spheroid dose after 4 years

PURPOSE

The aim of this study was to investigate the effect of product dose in autologous chondrocyte implantation (ACI) for the treatment of full-thickness cartilage defects of the knee and to assess its influence on clinical and morphological mid-term outcome.

METHODS

Seventy-five patients were included in this single-blind, randomised, prospective, controlled clinical trial. Patients were assigned randomly to three different dose groups [low (3-7 spheroids/cm²), medium (10-30 spheroids/cm²), or high (40-70 spheroids/cm²)] and assessed using standardised clinical and morphological scoring systems (KOOS, IKDC, MOCART) for 4 years following the intervention.

RESULTS

The analysis population comprised 75 patients (22 women, 53 men) aged 34 ± 9 years. Defect sizes ranged from 2 to 10 cm² following intraoperative debridement. The assessment of the primary variable 'overall KOOS' showed a statistically significant improvement, compared with baseline, for each dose group, i.e., at baseline the mean 'overall KOOS' scores were 60.4 ± 13.6, 59.6 ± 15.4, and 51.1 ± 15.4 for the low-, medium-, and high-dose groups, respectively, and 57.0 ± 15.2 for 'all patients'. After 48 months those values improved to 80.0 ± 14.7, 84.0 ± 14.9, and 66.9 ± 21.5 in the respective dose groups and 77.1 ± 18.6 for 'all patients'. Pairwise comparisons of these dose groups did not reveal any statistically significant differences. Likewise, assessment of the subjective IKDC score revealed no statistically significant differences between the three dose groups up to the 48-month visit. However, between 12 and 48 months there was a low, but steady, improvement in the low-dose group and a substantial amelioration in the medium-dose group. The mean MOCART total scores 3 months after treatment were 59.8 ± 10.9, 64.5 ± 10.3, and 64.7 ± 9.4 for the low-, medium-, and high-dose groups, and 62.9 ± 10.3 for 'all patients'; 48 months after treatment these were 73.9 ± 13.1, 78.0 ± 12.4, and 74.3 ± 14.0 for the respective dose groups and 75.5 ± 13.1 for 'all patients'.

CONCLUSIONS

Results of this study confirm the efficacy and safety of the applied "advanced therapy medicinal product"; no dose dependence was found either for the incidence or for the severity of any adverse reactions. All doses applied in the present study led to significant clinical improvement over time and can therefore be regarded as effective doses. The influence of product doses in the range investigated seems to be low and can be neglected. Thus, the authorised dose range of 10-70 spheroids/cm² confirmed by this clinical trial offers a broad therapeutic window for the surgeon applying the product, thereby reducing the risk of over- or underdosing.

LEVEL OF EVIDENCE

I.

Is debridement beneficial for focal cartilage defects of the knee: data from the German Cartilage Registry (KnorpelRegister DGOU)

INTRODUCTION

Focal cartilage defects of the knee are often treated with arthroscopic debridement. Existing literature discussing the benefit of debridement for small articular cartilage lesions is scarce, especially if the debridement was not part of a combined operative cartilage procedure including meniscal and ligament repair. The purpose of this study was to examine the patients´ benefit after arthroscopic debridement for the treatment of isolated focal chondral defects with or without partial meniscus resection.

MATERIALS AND METHODS

Baseline (preoperative data) and 12-month follow-up of the five Knee Osteoarthritis Outcome Score (KOOS) subscores and the Numeric Rating Scale (NRS) for pain were analyzed in 126 patients undergoing debridement for focal chondral defects of the knee from the German Cartilage Registry. Sub-analysis for patients receiving isolated debridement and debridement with concomitant partial resection of meniscal pathologies was performed. Thus, four subgroups were created according to the treated defect size and presence of meniscal pathologies: "debridement-only < 2 cm²", "debridement-only > 2 cm²", "debridement and partial meniscus resection < 2 cm²" and "debridement and partial meniscus resection > 2 cm²".

RESULTS

KOOS-subscores showed a significant increase from baseline to follow-up evaluation (p = 0.017-0.037) within the 126 patients. Sub-analysis showed significant improvement of all five KOOS-subscores in all three subgroups, except for the "debridement and partial meniscus resection > 2 cm²"-group: in this group the KOOS subscores symptoms and sports showed no significant improvement. The NRS scores revealed no significant changes from baseline to 12-month follow-up within the four subgroups.

CONCLUSION

An overall benefit of arthroscopic debridement for focal cartilage lesions of the knee could be conducted. Isolated cartilage defects seem to benefit from debridement irrespectively of size. In patients with large cartilage defects (> 2 cm²) and concurrent meniscal pathology expectation to improvement should be humbled. Effective reduction of pain by arthroscopic debridement remains unclear.

Validation of the Spanish Version of the Knee Injury and Osteoarthritis Outcome Score (KOOS) for Elderly Patients With Total Knee Replacement

The purpose of this study was to validate the Knee Injury and Osteoarthritis Outcome Score (KOOS) for elderly patients who undergo total knee replacement (TKR). The validated Spanish versions of the KOOS and Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) questionnaires were applied to 137 patients (mean age 72.3, SD 7.5 years). Test-retest data were collected with an intermediate period of 1-2 weeks. To evaluate the clinimetric properties of the KOOS, internal consistency (Cronbach's α), reproducibility (intraclass correlation coefficient [ICC]), construct validity (Spearman's correlation), responsiveness (effect sizes [ES], and standardized response mean [SRM]), and floor and ceiling effects (<15%) were assessed. As result, Cronbach's coefficients of the KOOS subscales ranged from 0.78 to 0.93, and ICC from 0.76 to 0.91. Construct validity was supported by the confirmation of the three predefined hypotheses involving expected correlations between KOOS subscale and SF-36 physical health subscales. Spearman's correlations were strong between KOOS Pain and SF-36 Bodily Pain (r = 0.81), KOOS Pain and SF-36 Physical Functioning (r = 0.67), KOOS activities of daily living (ADL) and SF-36 Bodily Pain (r = 0.69), KOOS ADL and SF-36 Physical Functioning (r = 0.74), and KOOS Sports/Recreation and SF-36 Physical Functioning (r = 0.76). Responsiveness at 1 year after TKR was large with the ES ranging from 0.81 to 2.12, and the SRM from 0.70 to 1.91. Floor and ceiling effects were low. In conclusion, the Spanish version of KOOS has successful psychometric characteristics and is a reliable and valid instrument for assessment of patient-relevant outcomes in elderly patients with advanced OA who undergo TKR. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2157-2162, 2019.

The effectiveness of Kinesio Taping® for pain management in knee osteoarthritis: a randomized, double-blind, controlled clinical trial

Background:

Kinesio Taping® method is a nonpharmacological alternative for pain management in musculoskeletal disorders. However, the existing evidence is insufficient to assess its full effectiveness for pain management in knee osteoarthritis (KO). Our aim was to evaluate the effectiveness of the Kinesio Taping method in reducing knee pain for KO patients.

Methods:

In this randomized, double blind, controlled trial, we recruited 187 patients with grade I-III KO who were allocated to either the Kinesio Taping or control group. The study was carried out in outpatient facility. Either Kinesio Taping or nonspecific taping was applied on the affected knee area for 4 weeks. Pain evaluation was performed at baseline, after 1 month of taping and after 1 further month without taping. The data on usage of painkillers were collected; Numeric Pain Rating Scale; an algometer, and Knee injury and Osteoarthritis Outcome Scores (KOOS) pain subscale were used to assess pain. Tolerance and subjective opinions toward the effectiveness of taping were evaluated. The chosen level of significance was p < 0.05, ß ⩽ 0.2.

Results:

The majority (>70%) of both groups’ patients indicated that tapes reduced the knee pain. The reported use of painkillers decreased, in addition to self-reported increase in the KOOS subscale, thereby indicating pain alleviation. All self-reported improvement remained at the 1-month follow up (p < 0.05). Significantly higher and clinically meaningful reduction of pain intensity was found in the Kinesio Taping group after the treatment month, in comparison with the control group (p < 0.05). More pain reduction was reported in the daytime for participants in the Kinesio Taping group at the follow up (p = 0.022). No changes in algometry results were observed.

Conclusions:

Elastic taping can safely relieve knee pain and reduce the need for pharmacological management in KO. A specific Kinesio Taping technique is clinically more beneficial for knee-pain alleviation in comparison with nonspecific taping.

[ClinicalTrials.gov identifier: NCT03076177.]

A Prospective, Randomized, Open-Label, Multicenter, Phase III Noninferiority Trial to Compare the Clinical Efficacy of Matrix-Associated Autologous Chondrocyte Implantation With Spheroid Technology Versus Arthroscopic Microfracture for Cartilage Defects of the Knee

Background:

Autologous chondrocyte implantation (ACI) and microfracture are established treatments for large, full-thickness cartilage defects, but there is still a need to expand the clinical and health economic knowledge of these procedures.

Purpose:

To confirm the noninferiority of ACI compared with microfracture.

Study Design:

Randomized controlled trial; Level of evidence, 2.

Methods:

Patients were randomized to be treated with matrix-associated ACI using spheroid technology (n = 52) or microfracture (n = 50). Both procedures followed standard methods. Patients were assessed by the Knee injury and Osteoarthritis Outcome Score (KOOS), MOCART (magnetic resonance observation of cartilage repair tissue) scoring system, Bern score, modified Lysholm score, International Cartilage Repair Society (ICRS) rating (histological and immunochemical scoring after rebiopsy 24 months after implantation), and International Knee Documentation Committee (IKDC) examination form. The main assessments were conducted 24 months after study treatment.

Results:

In the primary intention-to-treat analysis, the overall KOOS score for both ACI and microfracture yielded a statistically significant improvement relative to baseline. According to the between-group analysis, ACI passed the test of noninferiority compared with microfracture; thus, the primary goal of the study was achieved. The KOOS subscores yielded the same qualitative results as the overall KOOS score (ie, for each of these, noninferiority was demonstrated), and in 1 case (Activities of Daily Living subscore), the threshold for superiority was passed. The subgroup analyses did not yield any clear evidence of an association between treatment effect and any of the categories investigated (age, diagnosis, defect localization, sex). A histological analysis of biopsies from 16 patients (ACI: n = 9; microfracture: n = 7) suggested a better quality of repair in the patients treated with ACI.

Conclusion:

The efficacy of both ACI and microfracture was demonstrated with respect to both functional outcomes and morphological repair. The primary analysis confirmed the statistical hypothesis of the noninferiority of ACI, even for relatively small cartilage defects (1-4 cm²) treated in this study, the indication for which microfracture is generally accepted as the standard of care. ACI showed significant superiority in the KOOS subscores of Activities of Daily Living at 24 months and Knee-related Quality of Life at 12 months.

Registration:

NCT01222559 (ClinicalTrials.gov identifier).

Predictors of Pain and Function Before Knee Arthroscopy

BACKGROUND

Patient-reported outcome measures are commonly used to measure knee pain and functional impairment. When structural abnormality is identified on examination and imaging, arthroscopic partial meniscectomy and chondroplasty are commonly indicated for treatment in the setting of pain and decreased function.

PURPOSE

To evaluate the relationship between patient characteristics, mental health, intraoperative findings, and patient-reported outcome measures at the time of knee arthroscopy.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Between February 2015 and October 2016, patients aged 40 years and older who were undergoing routine knee arthroscopy for meniscal and cartilage abnormality, without reconstructive or restorative procedures, were prospectively enrolled in this study. Routine demographic information was collected, and the Knee injury and Osteoarthritis Outcome Score (KOOS) Pain, Quality of Life (QoL), and Physical Function Short Form (PS) subscales and the mental and physical component subscales of the Veterans RAND 12-Item Health Survey (VR-12 MCS and VR-12 PCS) were administered preoperatively on the day of surgery. Intraoperative findings were collected in a standardized format. Patient demographics, intraoperative findings, and the VR-12 MCS were used as predictor values, and a multivariate analysis was conducted to assess for relationships with the KOOS and VR-12 as dependent variables.

RESULTS

Of 661 eligible patients, baseline patient-reported outcomes and surgical data were used for 638 patients (97%). Lower scores on both subscales of the VR-12 were predicted by female sex, positive smoking history, fewer years of education, and higher body mass index (BMI). All KOOS subscales were negatively affected by lower VR-12 MCS scores, female sex, lower education level, and higher BMI in a statistically meaningful way. Positive smoking history was associated with worse scores on the KOOS-PS. Abnormal synovial status was associated with worse KOOS-Pain.

CONCLUSION

The demographic factors of sex, smoking status, BMI, and education level had an overwhelming impact on preoperative KOOS and VR-12 scores. Of interest, mental health as assessed by the VR-12 MCS was also a consistent predictor of KOOS scores. The only intraoperative finding with a significant association was abnormal synovial status and its effect on KOOS-Pain scores.

Listening to Patients' Voices: Workarounds Patients Use to Construct Pain Intensity Ratings

This study analyzed patients' perspectives about a measure of current, usual, and extreme pain and a measure of activity-related pain. Thirty-one patients with osteoarthritis participated in focus groups. Researchers completed thematic analysis of transcripts using coding software and an inductive approach. Three emerging themes were that many factors affected patients' perceptions and ratings of pain intensity, patients used different approaches to construct pain ratings, and patients interpreted maximal response anchors differently. Particularly, novel findings were that patients evaluated pain fluctuation, location, duration, and quality when constructing pain intensity ratings. Also, activity items helped patients to remember pain and provided a valued context for communicating pain experiences. However, the activities needed to be sufficiently described and personally relevant. These findings further clarify the challenges patients face and the workarounds they use when rating pain intensity. The patients' suggestions for improved administration methods and items warrant future investigation.

Mental Health Has No Predictive Association With Self-Assessed Knee Outcome Scores in Patients After Osteochondral Allograft Transplantation of the Knee

Background:

Patient-reported outcome (PRO) measures are progressively utilized as evaluation tools in preoperative and postoperative assessments in orthopaedic practice. Identifying the potential utility of psychosocial factors to predict patient-reported pain and functional outcomes is of increasing interest to determine which patients will derive the greatest benefit from surgical treatment.

Purpose/Hypothesis:

The purpose of this study was to determine potential predictive associations between the preoperative 12-Item Short Form Health Survey Mental Component Summary (SF-12 MCS) score, patient characteristics or osteochondral allograft (OCA) morphology, and PROs in patients who underwent OCA transplantation. We hypothesized that poor preoperative mental health is associated with diminished PROs at final follow-up.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

A total of 67 patients with a mean follow-up of 2.7 ± 1.0 years (range, 2-6 years) with complete preoperative and at least 24-month postoperative SF-12 MCS, Knee injury and Osteoarthritis Outcome Score (KOOS), Tegner, Lysholm, and International Knee Documentation Committee (IKDC) scores were included in this study. Pearson correlation coefficients and linear regression models were used to distinguish associations between age, sex, smoking status, body mass index, workers’ compensation, previous surgery, concomitant surgery, number of grafts, defect location, total graft size, SF-12 MCS score, and postoperative PRO scores as well as their improvement from baseline (delta).

Results:

The SF-12 MCS showed significant correlation with the KOOS Activities of Daily Living subscale (P = .015), KOOS Sport/Recreation subscale (P = .024), and IKDC (P = .039). In the multivariable linear regression models, the SF-12 MCS had no predictive association with any PRO measure. Patient sex contributed significantly to the final regression models of the KOOS Sport/Recreation (P = .042), Tegner score (P = .024), and Lysholm score (P = .031). The SF-12 MCS showed no bivariate correlation with changes in any PRO score (delta) (P > .05).

Conclusion:

Preoperative mental health status did not predict perceived functional outcomes as assessed by PRO measures at final follow-up. Female sex was negatively correlated with KOOS Sport/Recreation, Tegner, and Lysholm scores.

Subjects with medial and lateral tibiofemoral articular cartilage defects do not alter compartmental loading during walking

BACKGROUND

Healthy cartilage is essential for optimal joint function. Although, articular cartilage defects are highly prevalent in the active population and hamper joint function, the effect of articular cartilage defects on knee loading is not yet documented. Therefore, the present study compared knee contact forces and pressures between patients with tibiofemoral cartilage defects and healthy controls. Potentially this provides additional insights in movement adaptations and the role of altered loading in the progression from defect towards OA.

METHODS

Experimental gait data collected in 15 patients with isolated cartilage defects (8 medial involvement, 7 lateral-involvement) and 19 healthy asymptomatic controls was processed using a musculoskeletal model to calculate contact forces and pressures. Differences between two patient groups and controls were evaluated using Kruskal-Wallis tests and individually compared using Mann-Whitney-U tests (alpha <0.05).

FINDINGS

The patients with lateral involvement walked significantly slower compared to the healthy controls. No movement adaptations to decrease the loading on the injured condyle were observed. Additionally, the location of loading was not significantly affected.

INTERPRETATION

The current results suggest that isolated cartilage defects do not induce significant changes in the knee joint loading distribution. Consequently, the involved condyle will capture a physiological loading magnitude that should however be distributed over the cartilage surrounding the defect. This may cause local degenerative changes in the cartilage and in combination with inflammatory responses, might play a key role in the progression from articular cartilage defect to a more severe OA phenotype.

A Controlled Comparison of Microfracture, Debridement, and No Treatment of Concomitant Full-Thickness Cartilage Lesions in Anterior Cruciate Ligament-Reconstructed Knees: A Nationwide Prospective Cohort Study From Norway and Sweden of 368 Patients With 5-Year Follow-up

Background

The effect of microfracture (MF) or surgical debridement of concomitant full-thickness cartilage lesions in anterior cruciate ligament-reconstructed knees on patient-reported outcomes remains to be determined.

Purpose

To evaluate the effect of debridement or MF compared with no surgical treatment of concomitant full-thickness cartilage lesions on patient-reported outcomes 5 years after anterior cruciate ligament reconstruction (ACLR).

Study Design

Cohort study; Level of evidence, 2.

Methods

Included in this study were 644 patients who were registered in the Norwegian and the Swedish National Knee Ligament Registries from 2005 to 2008 as having undergone unilateral primary ACLR and having a concomitant full-thickness cartilage lesion (International Cartilage Repair Society [ICRS] grades 3-4). Of these patients, 129 were treated with debridement, 164 were treated with MF, and 351 received no surgical treatment simultaneously with ACLR. At 5-year follow-up, 368 (57%) patients completed results on the Knee injury and Osteoarthritis Outcome Score (KOOS). Multivariable linear regression was used to estimate the effect of surgical debridement or MF of concomitant full-thickness cartilage lesions on patient-reported outcomes 5 years after ACLR.

Results

Compared with no surgical treatment, there were no unadjusted or adjusted effects of debridement or MF of concomitant full-thickness cartilage lesions on KOOS scores at 5-year follow-up.

Conclusion

Compared with leaving concomitant full-thickness cartilage lesions untreated at the time of ACLR, debridement and MF showed no effect on patient-reported outcomes 5 years after surgery.

Effect of Concomitant Cartilage Lesions on Patient-Reported Outcomes After Anterior Cruciate Ligament Reconstruction: A Nationwide Cohort Study From Norway and Sweden of 8470 Patients With 5-Year Follow-up

Background:

The effect of concomitant focal cartilage lesions on patient-reported outcomes after anterior cruciate ligament reconstruction (ACLR) remains to be determined.

Purpose:

To evaluate the effect of concomitant partial-thickness (International Cartilage Repair Society [ICRS] grades 1-2) and full-thickness (ICRS grades 3-4) cartilage lesions on patient-reported outcomes 5 years after ACLR.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

All patients who underwent unilateral primary ACLR registered in the Norwegian and Swedish National Knee Ligament Registries from 2005 to 2008 (n = 15,783) were included in the study. At 5-year follow-up, 8470 (54%) patients completed the Knee injury and Osteoarthritis Outcome Score (KOOS). Multivariable linear regression models were used to estimate the effect of concomitant partial-thickness and full-thickness cartilage lesions on patient-reported outcomes (KOOS) 5 years after ACLR.

Results:

Compared with no concomitant cartilage lesions, both partial-thickness and full-thickness cartilage lesions were indicators of statistically significant adverse effects on the KOOS in the adjusted regression analysis at 5-year follow-up after ACLR.

Conclusion:

ACL-injured patients with concomitant cartilage lesions reported worse outcomes and less improvement than those without cartilage lesions 5 years after ACLR.

How Does the Presence of Unstable Chondral Lesions Affect Patient Outcomes After Partial Meniscectomy? The ChAMP Randomized Controlled Trial

BACKGROUND

Chondral lesions are commonly encountered during arthroscopic partial meniscectomy (APM); however, it is unknown how these lesions affect postoperative outcomes.

PURPOSE

The authors compared postoperative outcomes among patients with and without unstable chondral lesions 1 year after APM.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The authors conducted a secondary analysis of data from the ChAMP (Chondral Lesions and Meniscus Procedures) randomized controlled trial. They compared the following outcomes for patients with unstable chondral lesions that were left in situ and observed (CL-noDeb) versus patients without unstable chondral lesions (NoCL) at 1 year after APM: Western Ontario and McMaster Universities Osteoarthritis Index, Knee injury and Osteoarthritis Outcome Score, visual analog scale for pain, the Short Form Health Survey, range of motion, quadriceps circumference, and effusion. Multivariate linear regression was used to obtain mean differences (MDs) with corresponding 95% CIs adjusted for age, body mass index, and preoperative score (for postoperative scores).

RESULTS

Compared with the CL-noDeb group, the NoCL group had greater improvement in Western Ontario and McMaster Universities Osteoarthritis Index for pain (MD, 7.9, 95% CI: 2.7-13.1), stiffness (MD, 9.1, 95% CI: 1.9-16.3), and physical function (MD, 4.6, 95% CI: 0.1-9.0) and Knee injury and Osteoarthritis Outcome Score for pain (MD, 8.4, 95% CI: 2.7-14.0), function in sport and recreation (MD, 11, 95% CI: 3.0-19.1), and quality of life (MD, 10.4, 95% CI: 2.3-18.5). The NoCL group was less likely than the CL-noDeb group to have an effusion ( P = .02) 1 year after surgery.

CONCLUSION

Patients undergoing APM without unstable chondral lesions had better outcomes than patients with unstable chondral lesions.

Knee Pain and Mobility Impairments: Meniscal and Articular Cartilage Lesions Revision 2018

The Orthopaedic Section of the American Physical Therapy Association (APTA) has an ongoing effort to create evidence-based practice guidelines for orthopaedic physical therapy management of patients with musculoskeletal impairments described in the World Health Organization's International Classification of Functioning, Disability, and Health (ICF). The purpose of these revised clinical practice guidelines is to review recent peer-reviewed literature and make recommendations related to meniscus and articular cartilage lesions. J Orthop Sports Phys Ther. 2018;48(2):A1-A50. doi:10.2519/jospt.2018.0301.

A multilayer biomaterial for osteochondral regeneration shows superiority vs microfractures for the treatment of osteochondral lesions in a multicentre randomized trial at 2 years

PURPOSE

The increasing awareness on the role of subchondral bone in the etiopathology of articular surface lesions led to the development of osteochondral scaffolds. While safety and promising results have been suggested, there are no trials proving the real potential of the osteochondral regenerative approach. Aim was to assess the benefit provided by a nanostructured collagen-hydroxyapatite (coll-HA) multilayer scaffold for the treatment of chondral and osteochondral knee lesions.

METHODS

In this multicentre randomized controlled clinical trial, 100 patients affected by symptomatic chondral and osteochondral lesions were treated and evaluated for up to 2 years (51 study group and 49 control group). A biomimetic coll-HA scaffold was studied, and bone marrow stimulation (BMS) was used as reference intervention. Primary efficacy measurement was IKDC subjective score at 2 years. Secondary efficacy measurements were: KOOS, IKDC Knee Examination Form, Tegner and VAS Pain scores evaluated at 6, 12 and 24 months. Tissue regeneration was evaluated with MRI MOCART scoring system at 6, 12 and 24 months. An external independent agency was involved to ensure data correctness and objectiveness.

RESULTS

A statistically significant improvement of all clinical scores was obtained from basal evaluation to 2-year follow-up in both groups, although no overall statistically significant differences were detected between the two treatments. Conversely, the subgroup of patients affected by deep osteochondral lesions (i.e. Outerbridge grade IV and OCD) showed a statistically significant better IKDC subjective outcome (+12.4 points, p = 0.036) in the coll-HA group. Statistically significant better results were also found for another challenging group: sport active patients (+16.0, p = 0.027). Severe adverse events related to treatment were documented only in three patients in the coll-HA group and in one in the BMS group. The MOCART score showed no statistical difference between the two groups.

CONCLUSIONS

This study highlighted the safety and potential of a biomimetic implant. While no statistically significant differences were found compared to BMS for chondral lesions, this procedure can be considered a suitable option for the treatment of osteochondral lesions.

LEVEL OF EVIDENCE

I.

Joint awareness in posttraumatic osteoarthritis of the knee: validation of the forgotten joint score in long term condition after tibial plateau fracture

Background

Evaluating patient-reported outcomes (PRO) in early osteoarthritis (OA) of the knee is difficult. Established measurement tools are focused on one of the two major patient groups in knee surgery: young, highly active patients, or older patients with advanced degenerative OA of the knee. Joint awareness in everyday life is a crucial criterion in measuring PRO. The purpose of this study was to validate a German version of the “Forgotten Joint Score” (FJS) in patients after surgical treatment of tibial plateau fractures.

Methods

In this prospective cohort study, clinical and radiological outcomes data were collected from patients after surgical treatment of tibial plateau fractures following a skiing accident. Functional outcome questionnaires were administered including the FJS, the Lysholm-Score, the Tegner-Activity Scale (TAS), the EuroQol-5D (EQ 5-D), and a subjective rating of change. The validation study was carried out according to the COSMIN checklist protocol. The KLS was used to measure the presence and severity of OA on knee radiographs, and correlation with the FJS was measured.

Results

Cronbach‘s alpha was .96 (95%-CI .92, .99) confirming good internal consistency. Test-retest reliability of the FJS was high with an ICC₍₆₇₎ = .91 (95%-CI .85,.95). Furthermore, no relevant floor or ceiling effects were observed. FJS significantly differed in patients with different OA degrees (p = .041). Symptomatic patients had significant lower FJS than asymptomatic patients (p < .001).

Conclusions

This is the first study validating a disease-specific PRO, the FJS, in long-term outcomes after joint fracture. We demonstrated good psychometric properties and a significant correlation between the FJS and the radiologic degree of OA in patients with a history of tibial plateau fracture.

Trial registration

Clinical Trial Registry University of Regensburg Z-2015-0872-2. Registered 01. October 2015.

Human iPSC-derived chondrocytes mimic juvenile chondrocyte function for the dual advantage of increased proliferation and resistance to IL-1β

Background

Induced pluripotent stem cells (iPSC) provide an unlimited patient-specific cell source for regenerative medicine. Adult cells have had limited success in cartilage repair, but juvenile chondrocytes (from donors younger than 13 years of age) have been identified to generate superior cartilage. With this perspective, the aim of these studies was to compare the human iPSC-derived chondrocytes (hiChondrocytes) to adult and juvenile chondrocytes and identify common molecular factors that govern their function.

Methods

Phenotypic and functional characteristics of hiChondrocytes were compared to juvenile and adult chondrocytes. Analyses of global gene expression profiling, independent gene expression, and loss-of-function studies were utilized to test molecular factors having a regulatory effect on hiChondrocytes and juvenile chondrocyte function.

Results

Here, we report that the iPSC-derived chondrocytes mimic juvenile chondrocytes in faster cell proliferation and resistance to IL-1β compared to adult chondrocytes. Whole genome transcriptome analyses revealed unique ECM factors and immune response pathways to be enriched in both juvenile and iPSC-derived chondrocytes as compared to adult chondrocytes. Loss-of-function studies demonstrated that CD24, a cell surface receptor enriched in both juvenile chondrocytes and hiChondrocytes, is a regulatory factor in both faster proliferation and resistance to proinflammatory cues in these chondrocyte populations.

Conclusions

Our studies identify that hiChondrocytes mimic juvenile chondrocytes for the dual advantage of faster proliferation and a reduced response to the inflammatory cytokine IL-1β. While developmental immaturity of iPSC-derived cells can be a challenge for tissues like muscle and brain, our studies demonstrate that it is advantageous for a tissue like cartilage that has limited regenerative ability in adulthood.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-017-0696-x) contains supplementary material, which is available to authorized users.

The Effect of Body Mass Index on Clinical Outcomes in Patients Without Radiographic Evidence of Degenerative Joint Disease After Arthroscopic Partial Meniscectomy

PURPOSE

To examine the effect of obesity on clinical outcomes at 1 year after arthroscopic partial meniscectomy.

METHODS

We conducted a secondary analysis of the ChAMP (Chondral Lesions and Meniscus Procedures) randomized controlled trial (N = 256). The visual analog scale for pain, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), range of motion, and presence of effusion were assessed preoperatively and at 1 year after arthroscopic partial meniscectomy. Body mass index was categorized as normal weight, 24.99 or less; overweight, 25 to 29.99; or obese, 30 or greater. Analysis of variance or the Cochran-Mantel-Haenszel test was used to examine differences in clinical outcomes between body mass index categories, and mean ± standard deviation or number (percentage) is reported.

RESULTS

Preoperatively, obese patients had worse WOMAC pain (56.2 ± 17.2 vs 61.3 ± 17.2, P = .02), WOMAC physical function (55.8 ± 17.1 vs 62.8 ± 17.1, P = .004), pain visual analog scale (4.9 ± 2.1 vs 4.2 ± 1.9, P = .01), KOOS pain (49.5 ± 14.9 vs 54.0 ± 15.1, P = .02), and KOOS quality-of-life (27.9 ± 18.3 vs 36.9 ± 17.0, P = .001) scores, as well as decreased flexion (121.8° ± 22.6° vs 132.3° ± 16.5°, P = .003), compared with normal-weight patients. Overweight patients (n = 51 [51.5%], P = .03) and obese patients (n = 56 [52.8%], P = .002) were more likely to have knee effusion before surgery than normal-weight patients (n = 17 [34%]). At 1 year after surgery, overweight (130.2° ± 7.7°, P = .03) and obese (128.1° ± 7.1°, P = .003) patients had decreased flexion compared with normal-weight patients (134.5° ± 8.3°).

CONCLUSIONS

Obese patients had worse pain, physical functioning, and quality-of-life scores, as well as decreased flexion, compared with normal-weight patients before arthroscopic partial meniscectomy. At 1 year after arthroscopic partial meniscectomy, there were no statistically significant differences in clinical outcomes but obesity was associated with decreased knee flexion.

LEVEL OF EVIDENCE

Level II, prospective comparative trial.

Patient Outcomes After Observation Versus Debridement of Unstable Chondral Lesions During Partial Meniscectomy: The Chondral Lesions And Meniscus Procedures (ChAMP) Randomized Controlled Trial

BACKGROUND

It is unknown whether unstable chondral lesions observed during arthroscopic partial meniscectomy (APM) require treatment. We examined differences at 1 year with respect to knee pain and other outcomes between patients who had debridement (CL-Deb) and those who had observation (CL-noDeb) of unstable chondral lesions encountered during APM.

METHODS

Patients who were ≥30 years old and undergoing APM were randomized to receive debridement (CL-Deb group; n = 98) or observation (CL-noDeb; n = 92) of unstable Outerbridge grade-II, III, or IV chondral lesions. Outcomes were evaluated preoperatively and at 8 to 12 days, 6 weeks, 3 months, 6 months, and 1 year postoperatively. Outcome measures included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), visual analog scale (VAS) pain score, Short Form-36 (SF-36) health survey, range of motion, quadriceps circumference, and effusion. The primary outcome was the WOMAC pain score at 1 year. T tests were used to examine group differences in outcomes, and the means and standard deviations are reported.

RESULTS

There were no significant differences between the groups with respect to any of the 1-year outcome scores. Compared with the CL-Deb group, the CL-noDeb group had improvement in the KOOS quality-of-life (p = 0.04) and SF-36 physical functioning scores (p = 0.01) as well as increased quadriceps circumference at 8 to 12 days (p = 0.02); had improvement in the pain score on the WOMAC (p = 0.02) and KOOS (p = 0.04) at 6 weeks; had improvement in SF-36 physical functioning scores at 3 months (p = 0.01); and had increased quadriceps circumference at 6 months (p = 0.02).

CONCLUSIONS

Outcomes for the CL-Deb and CL-noDeb groups did not differ at 1 year postoperatively. This suggests that there is no benefit to arthroscopic debridement of unstable chondral lesions encountered during APM, and it is recommended that these lesions be left in situ.

LEVEL OF EVIDENCE

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

Differential knee joint loading patterns during gait for individuals with tibiofemoral and patellofemoral articular cartilage defects in the knee

OBJECTIVE

To determine compartment-specific loading patterns during gait, quantified as joint reaction forces (JRF), of individuals with knee articular cartilage defects (ACD) compared to healthy controls (HC).

METHODS

Individuals with ACDs and HC participated. Individuals with ACDs were divided into groups according to ACD location: PF (only a patellofemoral ACD), TF (only a tibiofemoral ACD), and MIX (both PF and TF ACDs). Participants underwent three-dimensional gait analysis at self-selected speed. TF joint reaction force (TF-JRF) was calculated using inverse dynamics. PF joint reaction force (PF-JRF) was derived from estimated quadriceps force (F_QUAD) and knee flexion angle. Primary variables of interest were the PF- and TF-JRF peaks (body weight [×BW]). Related secondary variables (gait speed, quadriceps strength, knee function, activity level) were evaluated as covariates.

RESULTS

First peak PF-JRF and TF-JRF were similar in the TF and MIX groups (0.75-1.0 ×BW, P = 0.6-0.9). Both peaks were also similar in the PF and HC groups (1.1-1.3 ×BW, P = 0.7-0.8), and higher than the TF and MIX groups (P = 0.004-0.02). For the second peak PF-JRF, only the HC group was higher than the TF group (P = 0.02). The PF group walked at a similar speed as the HC group; both groups walked faster than the TF and MIX groups (P < 0.001). With gait speed and quadriceps strength as covariates, no differences were observed in JRF peaks.

CONCLUSIONS

The results suggest the presence of a TF ACD (TF and MIX groups), but not a PF ACD (PF group), may affect joint loading patterns during walking. Walking slower may be a protective gait modification to reduce load.

Development of a pilot cartilage surgery register

Background

Norway has no prospective surveillance system to monitor the outcome of knee cartilage surgery. In 2004 the Norwegian Registry of Knee Ligament (NKLR) was successfully established, and has yielded useful information on the treatment of patients with both knee ligament and combined knee injuries. Patients with focal cartilage defects (FCDs) in their knees have reduced function and the treatment is difficult. There are geographical variations in treatment, and the generalizability from randomized controlled studies is low. These patients would benefit from a standardized long-time follow-up through a cartilage surgery register.

The aim of the present study was to describe the development and report baseline challenges during the setting up of a pilot of a knee cartilage surgery register.

Methods

The study was designed as a prospective cohort study in the form of a register. Patients with full-thickness FCDs in the knee with International Cartilage Repair Society (ICRS) grade 3–4 on arthroscopy were included. The pilot included two hospitals; Oslo University Hospital (OUS), Ullevål and Akershus University Hospital (Ahus).

Results

We registered 58 patients with isolated FCDs, whereas 16 additional patients with full-thickness FCDs were registered through the NKLR. The patient cohort of patients with isolated FCDs consisted of 65% men and had a mean age of 29.8 years. The data are incomplete and the compliance varies from 18 to 73%. The distribution of mean KOOS scores were similar to previous patient cohorts with FCDs, with low scores for the KOOS Sport/Recreation and Quality of Life subscales.

Conclusion

The level of compliance demonstrated a large difference between the two participating hospitals. The compliance for the isolated FCDs were low in both locations, although it reached an acceptable level in one hospital when patients with combined injuries from the NKLR were included. The forms were incompletely filled out by the surgeons postoperatively and need to be revised prior the establishment of a nation-wide register.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-017-1638-6) contains supplementary material, which is available to authorized users.

Return to running following knee osteochondral repair using an anti-gravity treadmill: A case report

BACKGROUND

The purpose of this study was to assess the impact of an anti-gravity treadmill return to running programme on self-efficacy and subjective knee function following knee osteochondral surgery.

CASE DESCRIPTION

A 39-year-old otherwise healthy female endurance runner with a left knee femoral cartilage grade 3-4 defect 3 cm². The patient underwent single step arthroscopic microfracture with Bone Marrow Aspirate Concentrate. An AlterG^® anti-gravity treadmill was used to manipulate loading during a graduated phased return to running over 8 weeks. Self-efficacy was evaluated using the Self-Efficacy for Rehabilitation outcomes scale (SER) and the Knee Self-Efficacy Scale (K-SES). Subjective knee function was evaluated using the Knee injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee Subjective Knee Form (IKDC).

OUTCOMES

The programme resulted in improvements in SER (57%), K-SES present (89%) and K-SES future (65%) self-efficacy domains. The IKDC score demonstrated a clinically important improvement with an increase from 62.1 in week 1-86.2 in week 8 (39%). Only the KOOS Sport/Rec subscale showed a clinically important improvement from week 1 to week 8.

DISCUSSION

The programme resulted in improved knee and rehabilitation self-efficacy and subjective knee function following osteochondral repair of the knee. This case report illustrates the importance of considering self-efficacy in rehabilitation after knee osteochondral surgery and highlights the potential role for anti-gravity treadmills in enhancing self-efficacy and subjective knee function in preparation for a return to sport.

Validity and Responsiveness of the Knee Injury and Osteoarthritis Outcome Score: A Comparative Study Among Total Knee Replacement Patients

OBJECTIVE

To evaluate validity and responsiveness of the Knee Injury and Osteoarthritis Outcome Score (KOOS) in relation to other patient-reported outcome measures before and after total knee replacement (TKR).

METHODS

Pre-TKR and 6-month post-TKR data from 1,143 patients in a US joint replacement cohort were used to compare the KOOS, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the SF-36 Health Survey (SF-36). Validity was evaluated with multiple methods, including correlations of pre-TKR scale scores and analysis of variance models that used pre-TKR data to compare the relative validity of scales in discriminating between groups differing in assistive walking device use and number of comorbid conditions. Validity was also evaluated by using post-TKR minus pre-TKR change scores to assess relative validity of scales in discriminating between groups rating themselves as better, same, or worse (BSW) in their capability to do activities at 6 months. Responsiveness also was described using effect sizes and standardized response means.

RESULTS

In support of convergent and discriminant validity, KOOS scale scores were worse for patients using an assistive device but only declined weakly with increasing comorbid conditions. While all knee-specific scales discriminated between BSW groups, the KOOS quality of life (QOL) scale was significantly better (P < 0.05) than all measures except the SF-36 physical component summary. KOOS QOL also had the highest effect size, while SF-36 measures had lower effect sizes and standardized response means. KOOS pain and symptoms scales discriminated better than WOMAC pain and stiffness scales among BSW groups.

CONCLUSION

KOOS scales were valid and responsive in this cohort of US TKR patients. KOOS QOL performed particularly well in capturing aggregate knee-specific outcomes.

No negative effect on patient-reported outcome of concomitant cartilage lesions 5-9 years after ACL reconstruction

PURPOSE

To compare patient-reported outcome 5-9 years after anterior cruciate ligament (ACL) reconstruction in patients with and without a concomitant full-thickness [International Cartilage Repair Society (ICRS) grade 3-4] cartilage lesion.

METHODS

This is a prospective follow-up of a cohort of 89 patients that were identified in the Norwegian National Knee Ligament Registry and included in the current study in 2007, consisting of 30 primary ACL-reconstructed patients with a concomitant, isolated full-thickness cartilage lesion (ICRS grade 3 and 4) and 59 matched controls without cartilage lesions (ICRS grade 1-4). At a median follow-up of 6.3 years (range 4.9-9.1) after ACL reconstruction, 74 (84 %) patients completed the Knee Injury and Osteoarthritis Outcome Score (KOOS), which was used as the main outcome measure. Secondary outcomes included radiographic evaluation according to the Kellgren-Lawrence criteria of knee osteoarthritis (OA).

RESULTS

At follow-up, 5-9 years after ACL reconstruction, no statistically significant differences in KOOS were detected between patients with a concomitant full-thickness cartilage lesion and patients without concomitant cartilage lesions. Radiographic knee OA of the affected knee, defined as Kellgren and Lawrence ≥2, was significantly more frequent in subjects without a concomitant cartilage lesion (p = 0.016).

CONCLUSION

ACL reconstruction performed in patients with an isolated concomitant full-thickness cartilage lesion restored patient-reported knee function to the same level as ACL reconstruction performed in patients without concomitant cartilage lesions, 5-9 years after surgery. This should be considered in the preoperative information given to patients with such combined injuries, in terms of the expected outcome after ACL reconstruction and in the counselling and decision-making on the subject of surgical treatment of the concomitant cartilage lesion.

LEVEL OF EVIDENCE

Prognostic; prospective cohort study, Level I.

How are we measuring clinically important outcome for operative treatments in sports medicine?

OBJECTIVES

Minimal clinically important difference (MCID) and other measures of minimum clinical importance are increasingly recognized as important clinical considerations for evaluating the efficacy of an intervention. As our interpretation of clinical outcome evolves beyond statistical significance, psychometric properties such as MCID will be increasingly important to various stakeholders in the orthopaedic community. The purpose of this study was to: 1) describe the state of clinically important outcome reporting and 2) describe the methods used to derive these psychometric values for sports medicine patients undergoing operative treatments.

METHODS

A review of the MEDLINE database was performed. Studies primarily deriving and reporting clinically important outcome measures for operative interventions in sports medicine were included. Demographic, methodological and psychometric properties of included studies were extracted. Level of Evidence and the Newcastle Ottawa Scale (NOS) were used to assess study quality. Statistical analysis was primarily descriptive.

RESULTS

Fifteen studies met inclusion criteria; 10 of the 15 studies were Level II evidence and mean NOS score was 5.3/9. Minimal detectable change (MDC) was the most commonly derived measure of clinical importance, calculated in 53.3% of studies, followed by MCID, calculated in 40.0% of studies. A combination of distribution and anchor-based methods was the most commonly used method to determine clinical importance (N = 7, 46.7%) followed by distribution only (N = 5, 33.3%). Predictors of clinically important change were reported in four studies and were most commonly related to pre-operative functional score.

CONCLUSIONS

MDC and the MCID are the most commonly reported measures of clinically important outcome after operative treatment in sports medicine. A combination of both distribution and anchor-based methods is commonly used to derive these values. More attention should be paid to reporting outcomes that are clinically important and developing guidelines for reporting clinical meaningful outcome.

Knee Injury and Osteoarthritis Outcome Score (KOOS): systematic review and meta-analysis of measurement properties

OBJECTIVE

To conduct a systematic review and meta-analysis to synthesize evidence regarding measurement properties of the Knee injury and Osteoarthritis Outcome Score (KOOS).

DESIGN

A comprehensive literature search identified 37 eligible papers evaluating KOOS measurement properties in participants with knee injuries and/or osteoarthritis (OA). Methodological quality was evaluated using the COSMIN checklist. Where possible, meta-analysis of extracted data was conducted for all studies and stratified by age and knee condition; otherwise narrative synthesis was performed.

RESULTS

KOOS has adequate internal consistency, test-retest reliability and construct validity in young and old adults with knee injuries and/or OA. The ADL subscale has better content validity for older patients and Sport/Rec for younger patients with knee injuries, while the Pain subscale is more relevant for painful knee conditions. The five-factor structure of the original KOOS is unclear. There is some evidence that the KOOS subscales demonstrate sufficient unidimensionality, but this requires confirmation. Although measurement error requires further evaluation, the minimal detectable change for KOOS subscales ranges from 14.3 to 19.6 for younger individuals, and ≥20 for older individuals. Evidence of responsiveness comes from larger effect sizes following surgical (especially total knee replacement) than non-surgical interventions.

CONCLUSIONS

KOOS demonstrates adequate content validity, internal consistency, test-retest reliability, construct validity and responsiveness for age- and condition-relevant subscales. Structural validity, cross-cultural validity and measurement error require further evaluation, as well as construct validity of KOOS Physical function Short form. Suggested order of subscales for different knee conditions can be applied in hierarchical testing of endpoints in clinical trials.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO (CRD42011001603).

Norwegican Cartilage Project - a study protocol for a double-blinded randomized controlled trial comparing arthroscopic microfracture with arthroscopic debridement in focal cartilage defects in the knee

Background

Focal lesions to the articular cartilage in the knee might have demolishing consequences to the knee. There exists a wide range of possible surgical procedures targeting these injuries, however no significant differences have been found between these procedures. This may support that the improvement is a result of rehabilitation, and not the surgery itself. Arthroscopic microfracture (MF) treatment has gained popularity, and has become the treatment of choice in patients with knee cartilage defects globally. In this study we want to increase knowledge, both clinical and economic, about arthroscopic microfracture (AF) compared to arthroscopic debridement (AD) and physical rehabilitation both in the short run, and in the long run.

Methods/Design

To compare arthroscopic microfracture with arthroscopic debridement and physiotherapy for the treatment of focal cartilage lesions in the knee, a long-term, double-blinded, randomized controlled multicenter trial will be conducted. A total of 114 men and non-pregnant women with a symptomatic focal full thickness cartilage lesion in the knee less than 2 cm2 will be included in the study. The two treatment allocations will receive identical rehabilitation, which is made up of 3 phases: accommodation, rehabilitation and return to activity. Follow up is 24 months, where all will be invited to participate in late follow ups after 5 and 10 years.

The Knee Injury and Osteoarthritis Outcome Score (KOOS) knee-related quality of life (QoL) subscore is the primary endpoint. Clinical parameters, questionnaires and radiologic modalities (Magnetic Resonance Imaging (MRI) and x-ray) will be used as secondary endpoints.

Discussion

This is an ongoing multicenter study with a high level of evidence to compare arthroscopic microfracture with arthroscopic debridement and physiotherapy for the treatment of isolated symptomatic full thickness cartilage lesions in the knee joint.

Trial registration

ClinicalTrials.gov ID: NCT02637505 (December 15, 2015).

Muscle co-contraction during gait in individuals with articular cartilage defects in the knee

Increased muscle co-contraction during gait is common in individuals with knee pathology, and worrisome as it is known to amplify tibiofemoral compressive forces. While knees with articular cartilage defects (ACD) are more vulnerable to compressive forces, muscle co-contraction has never been reported in this population. The purpose of this study was to evaluate the extent to which individuals with ACDs in the knee demonstrate elevated quadriceps to hamstrings muscle co-contraction on the involved limb during gait compared to the uninvolved limb and to healthy controls. We also explored the impact of participant characteristics and knee impairments on co-contraction. Twenty-nine individuals with full-thickness knee ACDs (ACD group) and 19 healthy adults (control group) participated in this study. Participants performed five gait trials at self-selected speed, during which activity of the quadriceps and hamstrings muscles were collected with surface electromyography. Three-dimensional motion capture was used to define phases of gait. Quadriceps strength and self-reported outcomes were also assessed in the same session. There were no differences in quadriceps: hamstrings co-contraction between the ACD and control groups, or between the involved and uninvolved limb for the ACD group. For both ACD and control groups, co-contraction was highest in early stance and lowest in late stance. Quadriceps strength was consistently the strongest predictor of muscle co-contraction in both the ACD and the control groups, with individuals with lower strength demonstrating greater co-contraction. Further study is needed to understand the effect of increased muscle co-contraction on joint compressive forces in the presence of varied quadriceps strength.

Focal cartilage defects in the knee - a randomized controlled trial comparing autologous chondrocyte implantation with arthroscopic debridement

BACKGROUND

Focal cartilage injuries in the knee might have devastating effect due to the predisposition of early onset osteoarthritis. Various surgical treatment options are available, however no statistically significant differences have been found between the different surgical treatments. This supports the suggestion that the improvement might be a result of the post-operative rehabilitation rather than the surgery itself. Autologous chondrocyte implantation (ACI) has become a recognized treatment option for larger cartilage lesions in the knee. Although ACI has been compared to other surgical treatment such as microfracture and mosaicplasty, it has never been directly compared to simple arthroscopic debridement and rehabilitation alone. In this study we want to increase clinical and economic knowledge about autologous chondrocyte implantation compared to arthroscopic debridement and physical rehabilitation in the short and long run.

METHODS/DESIGN

We will conduct a randomized controlled trial to compare ACI with simple arthroscopic debridement (AD) and physiotherapy for the treatment of cartilage lesions in the knee. The study will include a total of 82 patients, both men and non-pregnant women, with a full thickness cartilage defect in the weight bearing area of the femoral condyles or trochlea larger than 2 cm2. The lesion must be symptomatic, with a Lysholm score less than 75. The two treatment groups will receive identical rehabilitation protocol according to a modification of Wondrasch et al., which is an active rehabilitation and education program divided into 3 phases: accommodation, rehabilitation and return to activity. The patients will be followed for 24 months, with additional late follow-ups at 5 and 10 years to monitor the potential onset of osteoarthtitis. The primary outcome measure will be the difference in the KOOS knee-related quality of life (QoL) subscore in the ACI group compared to the AD group at 2 years. A combination of self-explanatory questionnaires, clinical parameters, clinical hop tests and radiographs and Magnetic Resonance Imaging (MRI) will be used as secondary endpoints.

DISCUSSION

This is the first study with a high level of evidence to compare ACI with simple debridement and physiotherapy for the treatment of isolated symptomatic full thickness lesions of the knee.

TRIAL REGISTRATION

ClinicalTrial NCT02636881 (21 December 2015).