Association between hip muscle strength/function and hip cartilage defects in sub-elite football players with hip/groin pain.

OBJECTIVE: To explore associations between hip muscle strength and cartilage defects (presence and severity) on magnetic resonance imaging (MRI) in young adults with hip/groin pain participating in sub-elite football. DESIGN: Sub-elite football players with hip/groin pain (>6 months) completed assessments of isometric hip strength and functional task performance. Hip cartilage defects were assessed using the Scoring Hip Osteoarthritis with MRI tool. This exploratory, cross-sectional study used logistic and negative binomial models to assess the relationships between hip muscle strength or functional task performance and hip cartilage defects, controlling for body mass index, age, testing site and cam morphology, incorporating sex-specific interaction terms. RESULTS: One hundred and eighty-two (37 women) sub-elite (soccer or Australian football) players with hip/groin pain (age 26 ± 7 years) were included. Greater hip extension strength was associated with higher cartilage total score (adjusted incidence rate ratio [aIRR] 1.01, 95%CI: 1.0 to 1.02, p = 0.013) and superolateral cartilage score (adjusted odds ratio (aOR) 1.03, 95% confidence interval (CI): 1.01 to 1.06, p < 0.01). In female sub-elite football players, greater hip external rotation strength was associated with lateral cartilage defects (aOR 1.61, 95%CI: 1.05 to 2.48, p = 0.03) and higher cartilage total score (aIRR 1.25, 95%CI: 1.01 to 1.66, p = 0.042). A one-repetition increase in one-leg rise performance was related to lower odds of superomedial cartilage defects (aOR 0.96, 95%CI: 0.94 to 0.99, p < 0.01). CONCLUSIONS: Overall, there were few associations between peak isometric hip muscle strength and overall hip cartilage defects. It is possible that other factors may have relevance in sub-elite football players. Additional studies are needed to support or refute our findings that higher one leg rise performance was associated with reduced superomedial cartilage defect severity and greater hip extension strength was related to higher cartilage defect severity scores.

Is running good or bad for your knees? A systematic review and meta-analysis of cartilage morphology and composition changes in the tibiofemoral and patellofemoral joints.

BACKGROUND: The general health benefits of running are well-established, yet concern exists regarding the development and progression of osteoarthritis. AIM: To systematically review the immediate (within 20 min) and delayed (20 min-48 h) effect of running on hip and knee cartilage, as assessed using magnetic resonance imaging (MRI). METHOD: Studies using MRI to measure change in hip or knee cartilage within 48 h pre- and post-running were identified. Risk of bias was assessed using a modified Newcastle-Ottawa Scale. Percentage change in cartilage outcomes were estimated using random-effects meta-analysis. Certainty of evidence was evaluated with the Grading of Recommendations Assessment, Development and Evaluation tool. RESULTS: Twenty-four studies were included, evaluating 446 knees only. One third of studies were low risk of bias. Knee cartilage thickness and volume decreased immediately after running, with declines ranging from 3.3% (95% confidence interval [CI]: 2.6%, 4.1%) for weight-bearing femoral cartilage volume to 4.9% (95% CI: 4.43.6%, 6.2%) for patellar cartilage volume. T1ρ and T2 relaxation times were also reduced immediately after running, with the largest decline being 13.1% (95% CI: -14.4%, -11.7%) in femoral trochlear cartilage. Tibiofemoral cartilage T2 relaxation times recovered to baseline levels within 91 min. Existing cartilage defects were unchanged within 48 h post-run. CONCLUSIONS: There is very low certainty evidence that running immediately decreases the thickness, volume, and relaxation times of patellofemoral and tibiofemoral cartilage. Hip cartilage changes are unknown, but knee changes are small and appear transient suggesting that a single bout of running is not detrimental to knee cartilage.

Importance of patellofemoral and tibiofemoral cartilage lesions on trajectory of self-reported outcomes in patients at high risk of knee OA: 4-6 years follow-up of patients undergoing meniscal surgery.

OBJECTIVE: We evaluated whether patient-reported outcome trajectories (i.e., changes over time) differed by intraoperative compartmental cartilage lesion pattern over 4-6 years following arthroscopic meniscal surgery. METHODS: In this ancillary study of the Knee Arthroscopy Cohort Southern Denmark cohort, we intraoperatively categorized cartilage lesions as isolated patellofemoral, isolated tibiofemoral, or combined patellofemoral/tibiofemoral. Participants completed the Knee injury and Osteoarthritis Outcome Score (KOOS) pre-operatively, at 3 and 12 months, and at 4-6 years post-operatively and reported overall satisfaction at final follow-up. Our main outcome was KOOS4 (grand mean of four subscale means). We evaluated whether KOOS4 scores changed over time according to cartilage lesion patterns using adjusted mixed linear regression. We also estimated probability of treatment satisfaction using logistic regression. RESULTS: Of 630 participants with complete cartilage scores, 280 (44%) were women, mean (standard deviation) age was 49 (13) years, and BMI was 27.3 (4.4) kg/m2. KOOS4 scores at baseline were slightly lower in all lesion groups compared to the no lesion group, yet only the combined group was statistically significantly lower. KOOS4 trajectories were similar across cartilage lesion patterns, but by final follow-up, adjusted mean KOOS4 scores were 6.8 (95% CI 2.2, 11.4) to 9.8 (1.1, 18.5) points lower in groups with cartilage lesions compared to the no lesion group. Probability of patient-reported satisfaction did not differ statistically by group. CONCLUSIONS: Though KOOS4 scores were slightly lower in groups with arthroscopically assessed cartilage lesions compared to the no lesion group, trajectories were similar across all groups.

Should return to pivoting sport be avoided for the secondary prevention of osteoarthritis after anterior cruciate ligament reconstruction? A prospective cohort study with MRI, radiographic and symptomatic outcomes.

OBJECTIVE: To evaluate if returning to pivoting sport following anterior cruciate ligament reconstruction (ACLR) is associated with longitudinal structural and symptomatic osteoarthritis outcomes. DESIGN: Eighty-one adults aged 18-50 years were followed prospectively 1- to 5-years post-ACLR. Return to pivoting sport was assessed at 1-, 3- and 5-years. Longitudinal changes in osteoarthritis features were evaluated from 1- and 5-year magnetic resonance imaging (MRI)s using MRI Osteoarthritis Knee Score (MOAKS). Radiographic osteoarthritis and self-reported knee symptoms, function and quality of life were assessed using the Osteoarthritis Research Society International (OARSI) atlas and Knee injury Osteoarthritis Outcome Score (KOOS), respectively, at 5 years post-ACLR. Generalised linear models (adjusted for baseline characteristics) assessed whether returning to pivoting sport was associated with risk of worsening osteoarthritis features on MRI, radiographic osteoarthritis and KOOS. RESULTS: Thirty participants returned to pivoting sport 1-year post-ACLR and 50 returned at any time (i.e., 1-, 3- or 5-years). Returning to pivoting sport was not associated with worsening of any MRI osteoarthritis feature (risk ratio (RR) range: 0.59-2.91) or 5-year KOOS (ß range: -2.73-3.69). Returning to pivoting sport at 1-year and up to 5-years post-ACLR was associated with a 50% (RR 0.49, 95%CI 0.10-2.37) and 40% (RR 0.60, 95%CI 0.16-2.17) reduced risk of radiographic osteoarthritis, respectively, but these risk reductions were inconclusive due to wide confidence intervals. CONCLUSION: After ACLR, returning to pivoting sport was not associated with increased risk of worsening knee osteoarthritis features on MRI, radiographic osteoarthritis or knee symptoms. Participation in pivoting sport need not be avoided as part of osteoarthritis secondary prevention strategies.

Early anterior cruciate ligament reconstruction does not affect 5 year change in knee cartilage thickness: secondary analysis of a randomized clinical trial.

OBJECTIVE: To compare 5-year change in femorotibial cartilage thickness in 121 young, active adults with an acute anterior cruciate ligament (ACL) tear randomized to a strategy of structured rehabilitation plus early ACL reconstruction (ACLR) or structured rehabilitation plus optional delayed ACLR. DESIGN: 62 patients were randomized to early ACLR, 59 to optional delayed ACLR. Magnetic resonance imaging (MRI) was acquired within 4 weeks of injury, at two- and 5-years follow-up. Main outcome was 5-year change in overall femorotibial cartilage thickness. Secondary outcomes included the location-independent cartilage ChangeScore, summarizing thinning and thickening in 16 femorotibial subregions. An exploratory as-treated comparison was performed additionally. RESULTS: Baseline and at least one follow-up MRI were available for 117 patients. Over 5 years, a comparable increase in overall femorotibial cartilage thickness was observed for patients randomized to early ACLR (n = 59) and patients randomized to optional delayed ACLR (n = 58, adjusted mean difference: -5 µm, 95% CI: [-118, 108]µm). However, the location-independent cartilage ChangeScore was greater in those treated with early ACLR than in patients treated with optional delayed ACLR (adjusted mean difference: 403 µm [119, 687]µm). As-treated analysis showed no between-group differences for the main outcome, while the location-independent cartilage ChangeScore was greater for patients treated with early (adjusted mean difference: 632 µm [268, 996]µm) or delayed ACLR (adjusted mean difference: 449 µm [108, 791]µm) than for patients treated with rehabilitation alone. CONCLUSIONS: In young active adults with acute ACL-injury, choice of treatment strategy for the injured ACL did not modify the magnitude of 5-year change in overall femorotibial cartilage thickness. TRIAL REGISTRATION: ISRCTN84752559.

Osteoarthritis year in review 2020: imaging.

This narrative "Year in Review" highlights a selection of articles published between January 2019 and April 2020, to be presented at the OARSI World Congress 2020 within the field of osteoarthritis (OA) imaging. Articles were obtained from a PubMed search covering the above period, utilizing a variety of relevant search terms. We then selected original and review studies on OA-related imaging in humans, particularly those with direct clinical relevance, with a focus on the knee. Topics selected encompassed clinically relevant models of early OA, particularly imaging applications on cruciate ligament rupture, as these are of direct clinical interest and provide potential opportunity to evaluate preventive therapy. Further, imaging applications on structural modification of articular tissues in patients with established OA, by non-pharmacological, pharmacological and surgical interventions are summarized. Finally, novel deep learning approaches to imaging are reviewed, as these facilitate implementation and scaling of quantitative imaging application in clinical trials and clinical practice. Methodological or observational studies outside these key focus areas were not included. Studies focused on biology, biomechanics, biomarkers, genetics and epigenetics, and clinical studies that did not contain an imaging component are covered in other articles within the OARSI "Year in Review" series. In conclusion, exciting progress has been made in clinically validating human models of early OA, and the field of automated articular tissue segmentation. Most importantly though, it has been shown that structure modification of articular cartilage is possible, and future research should focus on the translation of these structural findings to clinical benefit.

The role of thigh muscle and adipose tissue in knee osteoarthritis progression in women: data from the Osteoarthritis Initiative.

OBJECTIVE: To determine whether loss in thigh muscle strength in women concurrent with knee osteoarthritis progression is associated with reductions of muscle anatomical cross-sectional area (ACSA) or specific-strength (i.e., isometric force÷ACSA), and to explore relationships with local adiposity. DESIGN: Female participants from the Osteoarthritis Initiative with Kellgren-Lawrence grade ≤3, thigh isometric strength measurements, and thigh magnetic resonance images at year-two (Y2) and year-four (Y4) (n = 739, age 62 ± 9 years; body mass index measurements (BMI) 28.8 ± 5.9 kg/m2) were grouped into: (1) those with vs without symptomatic progression (≥9 increase in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)-pain [scale: 0-100]); and (2) those with vs without radiographic progression (≥0.7 mm reduction in minimum joint space width). The change in knee extensor and flexor ACSA and specific-strength, and subcutaneous and intermuscular fat (IMF) ACSAs were compared between progressors and non-progressors using analysis of covariance. RESULTS: Symptomatic progression was associated with a significantly greater loss (p < 0.001) of knee extensor ACSA (-2.0%, 95%CI -2.5, -1.5) compared to those without progression (-0.7%, 95%CI -1.0, -0.4), and greater loss (p = 0.020) of knee flexor specific-strength (-7.6%, 95%CI -11.5, -3.7; vs -2.4%, 95%CI -4.8, 0.0). Radiographic progression was associated with a significantly greater increase (p = 0.023) in IMF (+1.7%, 95%CI -0.1, +3.6) compared to those without progression (-0.6%, 95%CI -1.6, +0.3). CONCLUSION: The significant reduction in thigh muscle strength concurrent with symptomatic progression in women appears to be associated with loss of extensor muscle ACSA and flexor specific-strength. In contrast, radiographic progression appears to be unrelated to muscle properties, but to be associated with local (intermuscular) adiposity gains.

Is local or central adiposity more strongly associated with incident knee osteoarthritis than the body mass index in men or women?

OBJECTIVE: To determine whether central (abdominal) or peripheral (thigh) adiposity measures are associated with incident radiographic knee osteoarthritis (RKOA) independent of body mass index (BMI) and whether their relation to RKOA was stronger than that of BMI. DESIGN: 161 Osteoarthritis Initiative (OAI) participants (62% female) with incident RKOA (Kellgren/Lawrence grade 0/1 at baseline, developing an osteophyte and joint space narrowing (JSN) grade ≥1 by year-4) were matched to 186 controls (58% female) without incident RKOA. Baseline waist-height-ratio (WHtR), and anatomical cross-sectional areas of thigh subcutaneous (SCF) and intermuscular fat (IMF) were measured, the latter using axial magnetic resonance images. Logistic regression assessed the relationship between each adiposity measure and incident RKOA before and after adjustment for BMI, and area under receiver operating characteristic curves (AUC) for each adiposity measure was compared to that of BMI using chi-squared tests. RESULTS: BMI, WHtR, subcutaneous fat (SCF) and IMF were all significantly associated with incident RKOA when analysed separately, with similar effect sizes (odds ratio range 1.30-1.53). After adjusting for BMI, odds ratios (ORs) for WHtR, SCF and IMF were attenuated and no longer statistically significant. No measure of central or peripheral adiposity was significantly more strongly associated with incident RKOA than BMI. Results were similar for men and women. CONCLUSIONS: Although both central (WHtR) and peripheral (SCF and IMF) adiposity were significantly associated with incident RKOA, neither was more strongly associated with incident RKOA than BMI. The simple measure of BMI appears sufficient to capture the elevated risk of RKOA associated with greater amounts of localised adiposity.

Longitudinal change in thigh muscle strength prior to and concurrent with symptomatic and radiographic knee osteoarthritis progression: data from the Osteoarthritis Initiative.

OBJECTIVE: To investigate whether symptomatic and/or radiographic knee osteoarthritis (KOA) progression is associated with prior and/or concurrent change in thigh muscle strength in men or women. DESIGN: Osteoarthritis Initiative (OAI) participants with isometric muscle strength measurements at baseline, 2- and 4-year follow-up (n = 1785: 1016 women) were grouped into 1) those with vs without symptomatic progression (i.e., increase ≥9 in WOMAC-pain [scale: 0-100]); and 2) those with vs without radiographic progression (i.e., decrease in minimum joint space width (JSW) ≥0.7 mm) between year-two and year-four follow-up. Sex-specific changes in thigh muscle strength concurrent (between year-two and year-four follow-up) and prior to (between baseline and year-two follow-up) symptomatic and radiographic progression were compared between groups (progression vs no progression) using analysis of covariance, with adjustment for age and body mass index. RESULTS: In women, but not in men, loss in knee extensor and flexor strength was greater concurrent with symptomatic progression (extensors: -3.7%, 95% confidence interval [CI] -6.4, -0.9; flexors: -7.2% 95% CI -10.7, -3.7) than in women without symptomatic progression (extensors: -0.3%, 95% CI -1.9, 1.3, P = 0.030; flexors: -2.6%, 95% CI -4.7, -0.6, P = 0.018). No association was found between extensor or flexor strength loss concurrent to radiographic progression, in either men or women, nor any statistically significant association between prior change in muscle strength with symptomatic or radiographic progression. CONCLUSION: These findings suggest that there is concurrent but not prior longitudinal association between loss in muscle strength and symptomatic KOA progression that is specific to women.

Anterior knee pain following anterior cruciate ligament reconstruction does not increase the risk of patellofemoral osteoarthritis at 15- and 20-year follow-ups.

OBJECTIVE: To prospectively evaluate the relationship between the presence or persistence of anterior knee pain (AKP) during the first 2-years following anterior cruciate ligament reconstruction (ACLR) and patellofemoral osteoarthritis (PFOA) at 15- and 20-years. DESIGN: This study was ancillary to a long-term prospective cohort study of 221 participants following bone-patellar-tendon-bone ACLR. AKP was assessed at 1- and 2-years post-ACLR using part of the Cincinnati knee score with an additional pain location question (persistence defined as presence at both follow-ups). Radiographic PFOA (definite patellofemoral osteophyte) and symptomatic PFOA (patellofemoral osteophyte, with knee pain during past 4 weeks) was assessed at 15- and 20-years follow-up. We used generalized linear models with Poisson regression to assess the relationship between AKP and PFOA. RESULTS: Of the 181 participants (82%) who were assessed at 15-years post-ACLR (age 39 ± 9 years; 42% female), 36 (24%) and 33 (22%) had AKP at 1- and 2-years, respectively, while 14 (8%) reported persistent AKP. Radiographic and symptomatic PFOA was observed at 15-years in 130 (72%) and 70 (39%) participants, respectively, and at 20-years in 115 (80%) and 60 (42%) participants, respectively. Neither the presence nor persistence of AKP at 1- and/or 2-years post-ACLR was associated with significantly higher risk of radiographic or symptomatic PFOA at 15- or 20-years (risk ratios <2.1). CONCLUSIONS: Although AKP and PFOA were prevalent, AKP does not appear to be associated with long-term PFOA following ACLR.

Longitudinal bone, muscle and adipose tissue changes in physically active subjects - sex differences during adolescence and maturity.

OBJECTIVES: To explore changes in bone, muscle and adipose tissue composition in athletes with high physical activity levels at different stages of life. METHODS: Thigh MRIs were acquired at baseline and 2-year follow-up for 20 young (16±1 years) and 20 mature (46±5 years) athletes (10 males, 10 females, respectively). Longitudinal changes in cross-sectional areas (CSAs) of femoral bone, quadriceps muscle, and thigh subcutaneous (SCF) and intermuscular (IMF) adipose tissue were evaluated. RESULTS: Adolescent males displayed significant muscle (+5.0%, 95%CI: 0.8, 9.2) and bone growth (+2.9%, 95%CI: 1.3, 4.5), whereas adolescent females did not (muscle: +0.8%, 95%CI: -2.2, 3.8; bone: +1.9%, 95%CI: -2.1, 5.6). Adolescent and mature females showed significant SCF increases (+11.0%, 95%CI: 0.9, 21.1 and +6.0%, 95%CI: 0.6, 11.4, respectively), whereas adolescent and mature males did not (+7.2%, 95%CI: -8.0, 22.5 and +1.5%, 95%CI: -9.7, 11.8, respectively). Muscle and bone changes were highly correlated in adolescent males (r=0.66), mature males (r=0.75) and mature females (r=0.68) but not in adolescent females (r=-0.11). CONCLUSIONS: The results suggest sex-specific patterns of age-related change in bone, muscle and adipose tissue, and tight coupling of bone and muscle growth. Sex-specific bone-muscle-adipose tissue relationships may have implications for understanding sex differences in fracture risk.

Knee kinematics and kinetics are associated with early patellofemoral osteoarthritis following anterior cruciate ligament reconstruction.

OBJECTIVE: Patellofemoral osteoarthritis (PFOA) commonly occurs following anterior cruciate ligament reconstruction (ACLR). Our study aimed to compare knee kinematics and kinetics during a hop-landing task between individuals with and without early PFOA post-ACLR. DESIGN: Forty-five individuals (mean ± SD 26 ± 5 years) 1-2 years post-ACLR underwent 3T isotropic MRI scans and 3D biomechanical assessment of a standardised forward hop task. Knee kinematics (initial contact, peak, excursion) in all three planes and sagittal plane kinetics (peak) were compared between 15 participants with early PFOA (MRI-defined patellofemoral cartilage lesion) and 30 participants with no PFOA (absence of patellofemoral cartilage lesion on MRI) using analysis of covariance (ANCOVA), adjusted for age, BMI, sex and the presence of early tibiofemoral OA. RESULTS: Compared to participants without PFOA, those with early PFOA exhibited smaller peak knee flexion angles (mean difference, 95% confidence interval [CI]: -5.2°, -9.9 to -0.4; P = 0.035) and moments (-4.2 Nm/kg.m, -7.8 to -0.6; P = 0.024), and greater knee internal rotation excursion (5.3°, 2.0 to 8.6; P = 0.002). CONCLUSIONS: Individuals with early PFOA within the first 2-years following ACLR exhibit distinct kinematic and kinetic features during a high-load landing task. These findings provide new information regarding common post-ACLR biomechanical patterns and PFOA. Since management strategies, such as altering knee load, are more effective during the early stages of disease, this knowledge will help to inform clinical management of early PFOA post-ACLR.

Quality of life in anterior cruciate ligament-deficient individuals: a systematic review and meta-analysis.

BACKGROUND: Physical and psychological impairments impacting quality of life (QOL) are common following ACL reconstruction. Rehabilitation alone is an effective alternative to reconstruction for some patients, warranting the investigation of QOL in ACL-deficient individuals. PURPOSE: To report and compare QOL in ACL-deficient individuals with population norms and ACL-reconstructed groups, and investigate relationships between participant characteristics and QOL. STUDY DESIGN: Systematic review and meta-analysis. METHODS: We systematically identified and methodologically appraised all studies reporting QOL in ACL-deficient individuals ≥5 years following ACL rupture. Knee-related and health-related QOL scores in ACL-deficient cohorts were compared to ACL-reconstructed groups using a random-effects meta-analysis. Descriptive comparisons were made with population norms. RESULTS: Eleven studies reported QOL in 473 ACL-deficient individuals, a mean of 10 (range 5-23) years following ACL rupture. Eight studies reported knee-related QOL using the Knee injury and Osteoarthritis Outcome Score QOL subscale (KOOS-QOL); scores (mean±SD) ranging from 54±17 to 77±22 were impaired compared to population norms. Health-related QOL, measured with the SF-36 domain scores in five studies, was similar to population norms, but impaired compared to physically active populations. Meta-analysis revealed no significant differences in KOOS-QOL (mean difference (95% CI) 2.9 (-3.3 to 9.1)) and SF-36 scores (for all SF-36 domains except Vitality) between ACL-deficient and ACL-reconstructed groups. CONCLUSIONS: This systematic review found impaired knee-related QOL in ACL-deficient individuals ≥5 years after ACL rupture, compared to population norms. Meta-analysis revealed similar knee-related QOL in ACL-deficient and ACL-reconstructed groups, and no difference in health-related QOL scores for seven of the eight SF-36 domains.

Infrapatellar fat pad size, but not patellar alignment, is associated with patellar tendinopathy.

Patellar tendinopathy (PT) is one of the most common overuse injuries of the knee. Recent reports indicate that increased body mass is frequently associated with tendinopathy, not only biomechanically but biochemically. Abnormalities of other structures within the knee extensor mechanism [patellofemoral joint (PFJ) alignment and patellar tendon length] that can directly influence the strain distribution of the patellar tendon are inconsistently implicated in PT. The aim of this study was to compare the infrapatellar fat pad volume, patellar tendon length and PFJ alignment in people with chronic PT and a group of age-, gender-, height-, and activity-matched controls with normal tendons. Axial magnetic resonance (MR) images, from 26 participants with PT and 28 control participants were obtained. Fat pad size, patellar tendon length and PFJ alignment were measured digitally from the MR images, using measurement software, and the results compared between the PT group and control group. People with PT had a significantly larger fat pad than healthy controls when controlled for height (P=0.04). Patellar tendon length was not significantly different between groups (P=0.16), nor were there between-group differences for the measures of PFJ alignment (P=0.07-0.76). Thus, the infrapatellar fat pad may play an important role in PT.