Minimum Joint Space Width Research Articles

Bone changes in early inflammatory arthritis assessed with High-Resolution peripheral Quantitative Computed Tomography (HR-pQCT): A 12-month cohort study.

Erosion development is of crucial significance as it impacts prognosis and therapy decisions in patients with inflammatory joint diseases. Our study aimed to determine the sensitivity of high-resolution peripheral quantitative computed tomography (HR-pQCT) to detect change of bone surface over time and to identify erosion development in early inflammatory arthritis (EIA) patients. Moreover, the contribution of prognostic factors on periarticular bone damage in the first year of diagnosis assessed by HR-pQCT was explored. 46 patients with arthritic symptoms for less than one year, and a clinical diagnosis of inflammatory arthritis were prospectively imaged at baseline and 12-months. HR-pQCT scans of the 2nd and 3rd MCP joints and CR of the hands and feet were performed. Joint space width (JSW), total bone mineral density (Tt.BMD), erosion presence and volume were assessed with HR-pQCT. Scan-rescan precision was assessed to define an individual-level least significant change (LSC) criterion. Regression analyses explored prognostic factors for bone damage progression. We observed no significant group-level changes in JSW, Tt.BMD or erosion volume. 20% or fewer joints demonstrated individual-level changes greater than the LSC criterion for mean JSW, Tt.BMD and erosion volume. HR-pQCT detected more erosions than CR in the 2nd and 3rd MCP. Increased symptom duration at diagnosis was weakly associated (P<0.10) with lower JSW minimum and higher JSW standard deviation. Gradual degradation of JSW, proportional to symptom duration, was detected by HR-pQCT. EIA patients need to be closely monitored for exacerbation of arthritis and progression of periarticular bone damage.

Comparison of Joint Space Measurements between Supine and Weightbearing Anteroposterior Pelvis Radiographs for Patients Undergoing Hip Arthroscopy

Objectives:Osteoarthritis and joint space narrowing of the hip have been correlated with poor outcomes and conversion to arthroplasty after hip arthroscopy. However, a standardized protocol for radiographic measurement of minimal joint space width of the hip has not been developed. We hypothesized that minimal joint space width would be significantly lower on the affected side in weightbearing anteroposterior pelvis radiographs versus supine radiographs. We also hypothesized that radiographs with single-leg stance would show the lowest minimal joint space width.Methods:Thirty-one consecutive adult patients with hip pain were prospectively enrolled and each had single-leg and double-leg weightbearing and supine anteroposterior pelvis radiographs in a standardized position. Two independent investigators determined minimal joint space width. Differences between minimal JSW as well as intra- and interobserver reliability were calculated. One and 2-way analyses of variance (ANOVA) were used to compare the measurements. Power analysis determined that recruitment of 30 patients was necessary to achieve 90% power. P<0.05 was considered significant.Results:No significant differences in joint space width were found between supine or weightbearing radiographs for any pelvis site (Figure 1). Comparing those under 50 years of age to those older than 50 years of age, mean joint space width was 3.5±0.5 vs. 3.0±0.9 in the supine position, 3.2±0.8 vs. 3.0±1.0 during double-leg stance, and 3.5±0.5 vs. 3.0±1.1 during single-leg stance (P=0.002).Conclusion:Our data showed no significant difference in joint space width among anteroposterior single-leg or double-leg weightbearing or supine radiographs at any location measured. These findings suggest that either weightbearing or supine radiographs can be used to evaluate hip joint space width and that all locations provide a similar indication of joint space width. These findings support the use of a single view for the evaluation of JSW in patients with hip pain, which may allow for a less burdensome clinical workflow.Table 1. Supine (mm) WB double-leg stance (mm) WB single-leg stance (mm) P-value Lateral sourcil4.21.04.31.04.31.10.77Middle sourcil4.04.01.03.91.00.91Fovea3.43.41.03.30.90.95

Evaluating the structural effects of intra-articular sprifermin on cartilage and non-cartilaginous tissue alterations, based on sqMRI assessment over 2 years

Sprifermin (recombinant human fibroblast growth factor-18), a potential disease-modifying osteoarthritis (OA) drug, demonstrated dose-dependent effects on femorotibial cartilage thickness (by quantitative magnetic resonance imaging [MRI]) in the phase II FORWARD study. This post-hoc analysis evaluated the potential effects of sprifermin on several articular structures in the whole joint over 24 months using semi-quantitative MRI assessment. Patients aged 40-85 years with symptomatic radiographic knee OA, Kellgren-Lawrence grade 2 or 3, and medial minimum joint space width ≥2.5mm in the target knee were randomized (1:1:1:1:1) to receive three double-blinded, once-weekly, intra-articular injections of sprifermin 30μg or 100μg or placebo every 6 (q6mo) or 12 months. 1.5- or 3T MRIs were read using the Whole-Organ Magnetic Resonance Imaging Score (WORMS) system at baseline and 24 months. Change from baseline at 24 months on compartment and/or whole knee level was assessed for cartilage morphology, bone marrow lesions (BMLs), and osteophytes by delta-subregional and delta-sum (DSM) approaches. Menisci, Hoffa-synovitis, and effusion-synovitis were also evaluated for worsening. 549 patients were included. Dose-dependent treatment effects from baseline to 24 months were observed on cartilage morphology (sprifermin 100μg q6mo vs placebo; mean DSM (95% confidence interval [CI])-0.6 (-1.5, 0.2); less cartilage worsening) in the entire knee and BMLs sprifermin 100μg q6mo vs placebo; mean DSM (95% CI)-0.2 (-0.5, 0.1) in the patellofemoral compartment. No effects over 24 months were observed on osteophytes, menisci, Hoffa-synovitis or effusion-synovitis. Positive effects associated with sprifermin were observed for cartilage morphology changes, and BML improvement. There were no meaningful negative or positive effects associated with sprifermin in the other joint tissues examined.

Radiographic evaluation of knee osteoarthritis in predicting outcomes after arthroscopic partial meniscectomy

BackgroundKnee osteoarthritis (OA) severity is a predictor of outcomes after arthroscopic partial meniscectomy (APM). Magnetic resonance imaging (MRI) grading of OA is predictive of postoperative outcomes; this prospective study assessed whether radiographic grading is also predictive of outcomes. MethodsPatients who underwent APM between February 2015 and January 2016, underwent radiography and MRI ≤6 months before surgery, and had outcomes from the surgery date and one year later were included. Surgical failure was defined as <10-point improvement in the Knee Osteoarthritis Outcome Score pain subscore. Radiographs were evaluated using Kellgren-Lawrence (KL) grading and continuous and ordinal minimum joint space width (mJSW) measurements; cartilage loss on MRI was evaluated using a modified Outerbridge system. Predictive abilities were estimated using area under the receiver operating characteristic curve (AUC) with 95% confidence intervals (CIs). ResultsThe study cohort included 66 knees from 64 patients (32 women; mean age, 57.1 years; range, 45–77). Radiographic grading was not predictive of outcomes (KL, AUC = 0.541 [95% CI: 0.358, 0.724]; continuous mJSW, AUC = 0.482 [95% CI: 0.305, 0.659]; ordinal mJSW, AUC = 0.534 [95% CI: 0.433, 0.634]). Comparison of radiographs showing no joint space narrowing (KL grade 0–2) with corresponding MR images demonstrated that 48% of radiographs missed a clinically significant lesion (modified Outerbridge grade ≥ 3). MRI grading was predictive of outcomes (AUC = 0.720 [95% CI: 0.581, 0.859]). ConclusionsRadiographic grading of OA is not predictive of outcomes after APM; radiographs may miss clinically significant lesions. For outcome prediction, MRI should be used.

Intra-articular pathology affects outcomes after joint preserving surgery for osteonecrosis of the femoral head.

Currently, knowledge regarding the intra-articular pathology and its relationship to outcomes after joint-preserving surgery in patients with osteonecrosis of the femoral head (ONFH) is lacking. The purposes were to evaluate the intra-articular pathology and its relationship with outcomes of joint-preserving surgery in ONFH. We reviewed 41 hips with ONFH in 41 patients (27 women; mean age, 34.9years old) who underwent intertrochanteric curved varus osteotomy. Radiographic evaluations were based on pre-operative imaging studies, including radiographs, computed tomography (CT), and magnetic resonance imaging (MRI). Intra-articular pathology was evaluated by arthroscopic inspection of the femoral head, labrum, and acetabular cartilage during surgery. In addition, we performed radiographic measurements of the hip, including the collapse of the femoral head and minimal joint space width at threeyears post-operatively and at final follow-up. Arthroscopy revealed damage to the acetabular cartilage and labrum in 22 (54%) and 13 patients (32%), respectively. However, these lesions could be detected on imaging in only 13 (32%) and ten patients (24%), respectively. The change in joint space width after surgery was significantly higher in patients with cartilage degeneration and labral injury (P = 0.02, P = 0.02). Logistic regression analysis for subsequent progression of osteoarthritis showed an association with degenerative changes of articular cartilage and the labral tear as independent predictors (P = 0.001, P = 0.03). Our data demonstrate the presence of labral and acetabular cartilage lesions in ONFH patients, while images do not reveal the full extent of the tissue damage. These intra-articular pathologies can be associated with the outcomes after joint-preserving surgery.

Predicting knee replacement in participants eligible for disease-modifying osteoarthritis drug treatment with structural endpoints

Evaluate associations between 2-year change in radiographic or quantitative magnetic resonance imaging (qMRI) structural measures, and knee replacement (KR), within a subsequent 7-year follow-up period. Participants from the Osteoarthritis Initiative were selected based on potential eligibility criteria for a disease-modifying osteoarthritis (OA) drug trial: Kellgren-Lawrence grade 2 or 3; medial minimum joint space width (mJSW) ≥2.5mm; knee pain at worst 4-9 in the past 30 days on an 11-point scale, or 0-3 if medication was taken for joint pain; and availability of structural measures over 2 years. Mean 2-year change in structural measures was estimated and compared with two-sample independent t-tests for KR and no KR. Area under the receiver operating characteristic curve (AUC) was estimated using 2-year change in structural measures for prediction of future KR outcomes. Among 627 participants, 107 knees underwent KR during a median follow-up of 6.7 years after the 2-year imaging period. Knees that received KR during follow-up had a greater mean loss of cartilage thickness in the total femorotibial joint and medial femorotibial compartment on qMRI, as well as decline in medial fixed joint space width on radiographs, compared with knees that did not receive KR. These imaging measures had similar, although modest discrimination for future KR (AUC 0.62, 0.60, and 0.61, respectively). 2-year changes in qMRI femorotibial cartilage thickness and radiographic JSW measures had similar ability to discriminate future KR in participants with knee OA, suggesting that these measures are comparable biomarkers/surrogate endpoints of structural progression.

Knee joint distraction as treatment for osteoarthritis: a systematic review and meta-analysis

Purpose: Knee osteoarthritis (OA) is a common cause of invalidity and is often treated with a total knee arthroplasty (TKA). While TKA is considered cost-effective, reduces pain and improves function, it brings a greater risk of a future revision surgery when performed in younger patients. Knee joint distraction (KJD) is a joint-preserving OA treatment that may postpone TKA and with that possibly prevent a revision. In the past years, multiple studies have investigated this surgical treatment.The goal of this systematic review and meta-analysis is to evaluate short- and long-term clinical benefit and tissue structure changes after KJD treatment for knee OA. Methods: MEDLINE, EMBASE and Web of Science were searched for eligible clinical studies evaluating a change in at least one of: Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Visual Analogue Score of pain (VAS-pain), Knee injury and Osteoarthritis Outcome Score (KOOS), EuroQol-5D (EQ5D), radiographic joint space width (JSW) or MRI cartilage thickness after KJD. The primary clinical and structural outcome parameters were the WOMAC and minimum JSW, respectively. Random effects models were applied on all outcome parameters and outcomes were compared with control groups found in the included studies. For continuous data the mean difference (MD) and 95% confidence interval (95%CI) were calculated and for dichotomous data the risk difference and 95%CI, following the Cochrane handbook. Results: In total 11 articles reporting on 7 different KJD cohorts with in total 127 patients and 5 control groups at multiple follow-up moments were included, with 2 of the studies being randomized controlled trials (RCTs). The WOMAC (figure 1) was compared to pre-treatment in 3 cohorts after 1 year (patients n=62) and 2 years (n=59) and in 1 cohort after 5 years (n=20) and 9 years (n=8), showing a significant increase at all time points (all p<0.001). The VAS-pain showed similar results at the same 4 time points, as did the KOOS and EQ5D, which were evaluated only after 1 (n=42) and 2 (n=39) years. The minimum (figure 2) and mean JSW are reported in 3 cohorts after 1 (n=59) and 2 (n=59) years and in 1 cohort after 5 (n=20) and 7 (n=8) years. Both JSW measures were statistically significantly increased after 1 and 2 years, but after 5 and 7 years the JSW increase was no longer statistically significant. Similarly, the MRI cartilage thickness showed an increase at 1 and 2 years, but not at 5 years (all n=20). Complications were reported in 5 studies with 87 patients, with 57 patients developing one or more pin tract skin infections, giving a risk of pin tract infections of 63% (95%CI 45-81), the majority of which could be treated with oral antibiotics. Only a small amount of other complications occurred and were all treated successfully. Overall, clinical and structural outcomes were comparable with control groups, including high tibial osteotomy and TKA as compared after 1 and 2 years in the two RCTs. Apart from pin tract infections, complications were not different in severity and number between control groups and KJD. Conclusions: KJD causes clear benefit in clinical and structural parameters over time, both short- and long-term. Although the total number of patients is still limited, the effect sizes are large. Longer follow-up with more patients is necessary and could improve patient selection for this intensive treatment, while preventing pin tract infections could lighten the patients’ treatment burden. Irrespectively, KJD provides for an additional option in joint-preserving treatments for OA and a viable alternative to joint replacement, especially in younger patients.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Unravelling the role of WWP2 in the development and progression of osteoarthritis

Purpose: By applying a genome wide screen on allelic imbalanced (AI) expression of genes in cartilage, we identified rs1052429, located in the 3’UTR of WWP2, that showed highly significant AI with allele rs1052429-A (frequency∼0.7) marking higher expression of WWP2 relative to rs1052429-G. Moreover, rs1052429-A conferred risk to reduced minimal joint space width (P=0.0028). Notably, in a recent large meta-analyse of Icelandic and UK datasets WWP2 was also identified as OA susceptibility gene with a SNP in high LD (r2=0.60) with genome wide significance.

Quantitative 3D imaging parameters improve prediction of hip osteoarthritis outcome

Osteoarthritis is an increasingly important health problem for which the main treatment remains joint replacement. Therapy developments have been hampered by a lack of biomarkers that can reliably predict disease, while 2D radiographs interpreted by human observers are still the gold standard for clinical trial imaging assessment. We propose a 3D approach using computed tomography—a fast, readily available clinical technique—that can be applied in the assessment of osteoarthritis using a new quantitative 3D analysis technique called joint space mapping (JSM). We demonstrate the application of JSM at the hip in 263 healthy older adults from the AGES-Reykjavík cohort, examining relationships between 3D joint space width, 3D joint shape, and future joint replacement. Using JSM, statistical shape modelling, and statistical parametric mapping, we show an 18% improvement in prediction of joint replacement using 3D metrics combined with radiographic Kellgren & Lawrence grade (AUC 0.86) over the existing 2D FDA-approved gold standard of minimum 2D joint space width (AUC 0.73). We also show that assessment of joint asymmetry can reveal significant differences between individuals destined for joint replacement versus controls at regions of the joint that are not captured by radiographs. This technique is immediately implementable with standard imaging technologies.

Clinical phenotypes based on clinical prognostic factors in patients with secondary hip osteoarthritis: preliminary findings from a prospective cohort study.

Recently, several clinical prognostic factors for hip osteoarthritis (OA) progression such as spinal malalignment, reduced spinal mobility, and excessive daily cumulative hip loading have been identified. This study aimed to identify clinical phenotypes based on clinical prognostic factors in patients with secondary hip OA using data from prospective cohort studies and to define the clinical features of each phenotype. Fifty patients participated. Two-step cluster analysis was performed to identify the phenotypes using the following potential prognostic factors for hip OA progression: spinal inclination in standing, thoracolumbar spine mobility, daily cumulative hip moment, and minimum joint space width (JSW) at baseline. Comprehensive basic and clinical features (age, body mass index, hip pain, Harris hip score, JSW, radiographic hip morphology, hip impairments, spinal alignment and mobility, and gait-related variables) and ratio of progressors in 12months were compared among the phenotypes using bootstrap method (unadjusted and adjusted for age). Three phenotypes were identified and each phenotype was characterized as follows (P < 0.05): phenotype 1 (30%)-relatively young age and higher daily cumulative hip loading; phenotype 2 (42.0%)-relatively older age, reduced JSW, and less spinal mobility; and phenotype 3 (28.0%)-changed thoracic spine alignment and less spinal (especially in the thoracic spine) mobility. The ratio of progressors among the phenotypes was not statistically significantly different. These characteristics remained after adjustment for age. Three phenotypes with similar progression risk were identified. This finding will help in designing treatment tailored to each phenotype for hip OA progression prevention.Key Points• Three phenotypes with similar progression risk were identified based on clinical prognostic factors.• Phenotype 1 was characterized by young age and higher daily cumulative hip loading.• Phenotype 2 was relatively old age and had reduced JSW and less spinal mobility.• Phenotype 3 had changed thoracic spine alignment and less thoracic spine mobility.

Consensus approach for 3D joint space width of metacarpophalangeal joints of rheumatoid arthritis patients using high-resolution peripheral quantitative computed tomography.

Joint space assessment for rheumatoid arthritis (RA) by ordinal conventional radiographic scales is susceptible to floor and ceiling effects. High-resolution peripheral quantitative computed tomography (HR-pQCT) provides superior resolution, and may detect earlier changes. The goal of this work was to compare existing 3D methods to calculate joint space width (JSW) metrics in human metacarpophalangeal (MCP) joints with HR-pQCT and reach consensus for future studies. Using the consensus method, we established reproducibility with repositioning as well as feasibility for use in second-generation HR-pQCT scanners. Three published JSW methods were compared using datasets from individuals with RA from three research centers. A SPECTRA consensus method was developed to take advantage of strengths of the individual methods. Using the SPECTRA method, reproducibility after repositioning was tested and agreement between scanner generations was also established. When comparing existing JSW methods, excellent agreement was shown for JSW minimum and mean (ICC 0.987-0.996) but not maximum and volume (ICC 0.000-0.897). Differences were identified as variations in volume definitions and algorithmic differences that generated high sensitivity to boundary conditions. The SPECTRA consensus method reduced this sensitivity, demonstrating good scan-rescan reliability (ICC >0.911) except for minimum JSW (ICC 0.656). There was strong agreement between results from first- and second-generation HR-pQCT (ICC >0.833). The SPECTRA consensus method combines unique strengths of three independently-developed algorithms and leverages underlying software updates to provide a mature analysis to measure 3D JSW. This method is robust with respect to repositioning and scanner generations, suggesting its suitability for detecting change.

The posterior-anterior-flexed view is essential for the evaluation of valgus osteoarthritis. A prospective study on 134 valgus knees

BackgroundRadiographic imaging is an important tool to assess osteoarthritis (OA). Lateral compartment osteoarthritis (valgus OA) usually starts with cartilage degeneration along the posterior aspect of the lateral femoral condyle. There is evidence that the posterior-anterior (PA)-flexed view is more sensitive when diagnosing early stages of valgus OA compared to the anterior-posterior (AP) view. The current paper analyzes the value of the PA-flexed view for patients scheduled for total knee arthroplasty (TKA).MethodsRadiographs of 134 valgus knees were assessed prior to TKA. The minimal joint space width (minJSW) was measured on AP and PA-flexed views. The extent of mechanical deformity was measured on hip to ankle standing films.Results49 (36.6%) AP views showed Kellgren and Lawrence (K/L)-grade 4 osteoarthritis in the lateral compartment, 82 (63.4%) showed grade 3 or less. The PA-flexed view resulted in an increased K/L-grading to grade 4 for 53 knees (62.4%) that were considered grade 3 or less on standard AP-radiographs. There was a significant differences between lateral minJSW on AP and PA-flexed view for patients with up to 10 degrees of mechanical valgus deformity (p < 0.001), as well as 11 to 15 degrees of mechanical deformity (p = 0.021). Only knees with severe deformity of more than 15 degrees did not show a difference in minJSW between PA-flexed view and AP view (p = 0.345).ConclusionsThe PA-flexed view is superior to the standard AP view in quantifying the extent of valgus OA in patients with zero to fifteen degrees of valgus deformity. It is recommended for the initial assessment of patients with valgus osteoarthritis and better documents the extent of osteoarthritis prior to TKA.

Patellofemoral Chondromalacia Does Not Influence Radiographic and Clinical Outcomes following High Tibial Osteotomy.

Effect of patellofemoral (PF) chondromalacia on results of high tibial osteotomy (HTO) has not been identified. Therefore, the objective of the present study was to analyze the effect of PF chondromalacia on relatively short-term radiographic and clinical outcomes of HTO. Patients who underwent open wedge HTO (OWHTO) from February 2010 to January 2015 were enrolled. A total of 101 knees were divided into two groups: 56 knees without PF chondromalacia in group A, while 45 knees with PF chondromalacia extended to subchondral bone in group B. Radiologic outcomes were compared using mechanical tibiofemoral angle, ratio of weight-bearing line (WBL), and minimal joint space width of the lateral compartment. Clinical outcomes were compared using range of motion in affected knee, visual analog scale, modified Lysholm score, and Kujala score. The mean mechanical tibiofemoral angle was 4.6 degree in group A and 4.8 degree in group B. The mean ratio of WBL was 63.8% in group A and 63.6% in group B at final. The mean minimum joint space width of the lateral compartment was 5.8 mm in group A and 5.8 mm in group B on standing AP radiograph. It was 5.3 mm in group A and 5.4 mm in group B on Rosenburg view at final. The mean ROM was 137.2 degree in group A and 137.5 degree in group B. The mean visual analog scale was 2.1 in group A and 2.3 in group B at final. The mean modified Lysholm score was 90.6 in group A and 89.1 in group B at final. The mean Kujala score was 90.2 in group A and 89.1 in group B at final. PF chondromalacia does not influence short-term radiographic and clinical outcomes following OWHTO.

In vivo analysis of subchondral trabecular bone in patients with osteoarthritis of the knee using second-generation high-resolution peripheral quantitative computed tomography (HR-pQCT).

Subchondral bone plays an important role in the pathological mechanisms of knee osteoarthritis (OA). High-resolution peripheral quantitative computed tomography (HR-pQCT) is an imaging modality allowing noninvasive microstructural analysis of human bone, and the second generation enables scanning of the knee. The purpose of this study was to perform in vivo analysis of subchondral trabecular bone in patients with medial knee OA, to elucidate features of bone microstructure in medial knee OA, and to investigate relationships between bone microstructure and both stage of disease and lower limb alignment. Subjects were 20 women, including both patients with medial knee OA (Kellgren-Lawrence (KL) grade 2, n = 5, KL grade 3, n = 7, and KL grade 4, n = 4; mean age: 63.0 years; body mass index (BMI): 23.8 kg/m2) and volunteers without knee OA (KL grade 1, n = 4, mean age: 66.0 years; BMI: 23.8 kg/m2). The proximal tibia (20-mm length) was scanned by second-generation HR-pQCT at a voxel size of 60.7 μm. A subchondral trabecular bone volume of 5 mm length was extracted from the medial and lateral plateaus. They were then divided into 4 regions: anterior, central, medial or lateral, and posterior. Finally, subchondral bone microstructure parameters were analyzed and compared, between each plateau and region. Relationships between microstructural parameters and disease stage (KL grade, minimum joint space width), and between those parameters and lower limb alignment (femorotibial angle: FTA, mechanical axis deviation: MAD) were also investigated. In the medial plateau, volumetric bone mineral density (vBMD), bone volume fraction (BV/TV), and trabecular thickness were significantly higher and structure model index (SMI) was significantly lower than in the lateral plateau, particularly in the anterior, central, and medial regions (p < .01 each). In the anterior region of the medial plateau, vBMD, BV/TV, and connectivity density showed strong positive correlations with KL grade, FTA, and MAD (r-range: 0.61 to 0.83), while trabecular separation and SMI exhibited strong negative correlations with KL grade, FTA, and MAD (r-range: -0.60 to -0.83). Higher bone volume, trabecular thickness, and a more plate-like structure were observed in the medial tibial plateau than in the lateral. Subchondral bone microstructure at the anterior region in the medial plateau showed strong relationships with KL grade and lower limb alignment. These results indicate that subchondral bone microstructure in this region may provide representative indices, particularly in medial knee OA. Although this study involved a specifically Asian cohort with a lower BMI distribution than other ethnic groups, the technique presented may be useful in studying the pathogenesis of OA or evaluating treatment effects.

Predictive value of digital radiographic characteristics in combination with clinical evaluation scores in assessing the need for knee replacement

To investigate the possibility of a combination of knee digital radiography (DR) characteristics and pain numerical rating scale (NRS) scores in predicting the need for knee replacement (KR). This follow-up study was approved by the local medical ethics review boards, and informed consent was obtained from the participants. Knee osteoarthritis (KOA) patients who underwent KR (n = 106; 90 females) and those who did not (n = 103; 78 females) along with normal controls (n = 104; 81 females) were followed up from December 2016 to March 2018. The minimum knee joint space width (MJSW) on radiographs, Kellgren–Lawrence (KL) grade, NRS scores, age at operation, and body weight were statistically analysed by binary logistic regression, ROC curves, and Kaplan–Meier analysis. Measurement reliability was assessed by using intraclass correlation coefficient (ICC) values. The results showed a high reliability (ICC > 0.98). NRS and MJSW showed a higher value for predicting KR (odds ratios 2.76 and 2.21, respectively). The combination of MJSW ≤ 2.08 mm and NRS score > 3.75 had better predictive value than either index alone. The MJSW, an imaging characteristic derived from DR, and NRS scores have some predictive value for determining the need for KR in patients with KOA.

Relationships between Morphological Changes of Lower Limbs and Gender During Medial Compartment Knee Osteoarthritis

ObjectivesTo evaluate the dynamic changes of key morphology indicators of the lower extremities in the coronal plane with progressing medial compartment knee osteoarthritis (KOA) with an emphasis on gender‐dependent regional differences.MethodsThe radiographs of patients with non‐traumatic knee pain and varying degrees of genu varus were reviewed. Radiographs were studied in 1538 lower limbs of 883 consecutive patients who visited our hospital from January to July 2017; all patients had long‐standing anteroposterior image‐splicing radiographs taken of their lower limbs. Morphological indicators of bones and joints that can change the alignment of lower limbs or reflect cartilage wear and soft‐tissue relaxation were selected and measured with the help of picture archiving and communication systems. After comparing the data of different genders, the data of males and females was separated into three age groups, <40 years, 40–60 years, >60 years respectively, and then compared among age groups using the Kruskal‐Wallis and Mann–Whitney U tests. Scatterplots of age and all the measurements were drawn to determine the strength of the relations. The Pearson correlation test was performed to reveal correlations of measurements and age.ResultsFemoral bowing angle (FBA) and joint line convergence angle (JLCA) have obvious differences between different genders (P = 0.001, 0.000, respectively). This suggests that females have greater femoral curvature and joint space angle than males. Significant differences were found in hip‐knee‐ankle angle (HKA), FBA, distal femoral valgus resection angle (DFVRA), medial proximal tibial angle (MPTA), JLCA, and minimum joint space width (min‐JSW) by age groups in females (P = 0.000, 0.000, 0.000, 0.000, 0.003, 0.002, respectively). The difference of mechanical medial distal femoral angle (mMDFA) was significant with P values less than 0.05 deemed significant (P = 0.030). Significant correlations were found between age and all measurements (r = −0.166, 0.253, 0.270, −0.147, 0.089, −0.105, −0.076, respectively, P < 0.01). Whereas, the difference in min‐JSW by age group was the only significant one in males (P = 0.001), and no significant correlation was found between age and measurements (r = −0.107, 0.041, 0.134, −0.067, 0.079, −0.134, −0.098, respectively, P > 0.01).ConclusionsAs KOA progressed, both dynamic deformation of lower extremities and degeneration of articular cartilage could be found in females, while no obvious dynamic deformations were found in males. Dynamic deformation of lower extremities was the important feature and the major causative factor of KOA in females.

What Preoperative Factors are Associated With Not Achieving a Minimum Clinically Important Difference After THA? Findings from an International Multicenter Study.

AbstractBackgroundDespite innovations in THA, there remains a subgroup of patients who experience only modest pain relief and/or functional improvement after the procedure. Although several studies have previously sought to identify factors before surgery that were associated with achieving or not a

Knee Joint Distraction Compared with High Tibial Osteotomy and Total Knee Arthroplasty: Two-Year Clinical, Radiographic, and Biochemical Marker Outcomes of Two Randomized Controlled Trials.

ObjectiveBoth, knee joint distraction (KJD) and high tibial osteotomy (HTO) are joint-preserving surgeries that postpone total knee arthroplasty (TKA) in younger osteoarthritis (OA) patients. Here we evaluate the 2-year follow-up of KJD versus TKA and KJD versus HTO in 2 noninferiority studies.DesignKnee OA patients indicated for TKA were randomized to KJD (n = 20; KJDTKA) or TKA (n = 40). Medial compartmental knee OA patients considered for HTO were randomized to KJD (n = 23; KJDHTO) or HTO (n = 46). Patient-reported outcome measures were assessed over 2 years of follow-up. The radiographic joint space width (JSW) was measured yearly. In the KJD groups, serum-PIIANP and urinary-CTXII levels were measured as collagen type-II synthesis and breakdown markers. It was hypothesized that there was no clinically important difference in the primary outcome, the total WOMAC, when comparing KJD with HTO and with TKA.ResultsBoth trials were completed, with 114 patients (19 KJDTKA; 34 TKA; 20 KJDHTO; 41 HTO) available for 2-year analyses. At 2 years, the total WOMAC score (KJDTKA: +38.9 [95%CI 28.8-48.9] points; TKA: +42.1 [34.5-49.7]; KJDHTO: +26.8 [17.1-36.6]; HTO: +34.4 [28.0-40.7]; all: P < 0.05) and radiographic minimum JSW (KJDTKA: +0.9 [0.2-1.6] mm; KJDHTO: +0.9 [0.5-1.4]; HTO: +0.6 [0.3-0.9]; all: P < 0.05) were still increased for all groups. The net collagen type-II synthesis 2 years after KJD was increased (P < 0.05). Half of KJD patients experienced pin tract infections, successfully treated with oral antibiotics.ConclusionsSustained improvement of clinical benefit and (hyaline) cartilage thickness increase after KJD is demonstrated. KJD was clinically noninferior to HTO and TKA in the primary outcome.

What Is the Prevalence of Cam Deformity After Prophylactic Pinning of the Contralateral Asymptomatic Hip in Unilateral Slipped Capital Femoral Epiphysis? A 10-year Minimum Followup Study.

Prophylactic pinning of the asymptomatic and normal-appearing contralateral hip in patients with unilateral slipped capital femoral epiphysis (SCFE) remains controversial. Understanding the minimal 10-year clinical, functional, and radiographic outcomes of the contralateral asymptomatic hip in unilateral SCFE may be helpful in the decision regarding whether the benefits associated with potentially preventing a SCFE are outweighed by the risk of additional surgery. Among patients with SCFE treated with prophylactic pinning of the asymptomatic and contralateral hip, we sought (1) to determine the complications and reoperations; (2) to evaluate the development of cam deformities and the frequency and severity of osteoarthritis progression; and (3) to characterize hip pain and function as measured by the Harris hip score (HHS) and the Hip Disability and Osteoarthritis Outcome Score (HOOS) at minimal 10-year followup. Between 1998 and 2005 all patients with SCFE seen at our institution were treated with the modified Dunn procedure and all were offered prophylactic pinning of the contralateral asymptomatic hip. Of the 41 patients who underwent the unilateral modified Dunn procedure and who had an asymptomatic contralateral hip, 37 patients (90%) underwent pinning of that contralateral hip. Of those, 33 patients (80%) were available for clinical and radiographic evaluation for this retrospective study at a minimum of 10 years (mean followup 12 ± 2 years) after surgery. Three patients of the 37 patients only had 10-year clinical followup, including questionnaires sent by mail and telephone, because they refused further radiographic followup and one patient was lost to followup. The group included 19 males and 17 females whose age at surgery was a mean of 13 ± 2 years. Medical charts were reviewed and patients were asked about complications and additional surgical procedures. Most recent postoperative radiographs were evaluated for measurement of the alpha angle, head-neck offset, epiphysis orientation, and osteoarthritis grading according to Tönnis classification and minimum joint space width. The presence of a cam deformity was defined by an alpha angle measurement > 60° on the AP radiograph and/or > 55° on the lateral radiograph. Hip function and pain were assessed by the HHS and HOOS outcome measures. No complications with prophylactic in situ pinning were recorded. Four of 36 (11%) patients underwent subsequent surgical treatment for cam-type femoroacetabular impingement (FAI), and hardware removal was performed in four hips (11%). The mean alpha angle was 53° ± 8° on the AP radiograph and 49° ± 8° on the lateral view at followup. In total, 10 of 33 hips (30%) had a cam morphology at the femoral head-neck junction and four (12%) were symptomatic and underwent FAI surgery. Six of 33 patients (18%) developed an asymptomatic cam morphology at the femoral head-neck junction; in three of 33 hips (9%), the cam deformity instead of lesion were visible only on the lateral projection, and 9% were visible on both the AP and lateral projections. The preoperative offset of the femoral head-neck junction was 10 ± 3 mm on the AP view and 11 ± 4 mm on the lateral view. At followup, the AP offset was 7 ± 3 mm and the lateral offset was 6 ± 3 mm, and on the lateral view, the offset was < 10 mm in eight hips (22%). No patient had radiographic signs of hip osteoarthritis (Tönnis Grade 0). The mean minimum joint space width was 4 ± 0.4 mm. The mean HHS for the 32 patients who did not undergo subsequent surgery was 97 ± 5 at latest followup. The mean postoperative HOOS was 94 ± 8 for the 32 patients at latest followup. At a minimum followup of 10 years after prophylactic pinning of a contralateral asymptomatic hip, most patients achieve excellent hip scores; however, a substantial proportion will develop a symptomatic cam deformity despite prophylactic pinning. No patient had signs of osteoarthritis at a minimum of 10 years, but almost one-third of the patients who underwent prophylactic pinning developed a cam deformity. Level IV, therapeutic study.

Patient satisfaction after total knee arthroplasty is better in patients with pre-operative complete joint space collapse

Aim of the studyTo determine if pre-operative radiologic minimal joint space width (mJSW) is related to the outcome of total knee arthroplasty (TKA) (primary hypothesis). Likewise, the aim was to test if pre-operative mJSW is related to prosthesis survival (secondary hypothesis).MethodsA retrospective comparative analysis was performed. Group 1 was comprised of patients with pre-operative mJSW 0–1 mm. Group 2 were patients with pre-operative mJSW ≥ 2 mm. The clinical outcome was determined with the Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC) score pre-operatively and one year after TKA. Only patients with pre-operative weight-bearing radiographs and complete WOMAC score data were accepted.ResultsAvailable for analysis were 377 patients, of whom 188 were allocated to Group 1 (118 female, 70 male, age 70 ± 11 years) and 189 to Group 2 (118 female, 71 male, age 70 ± 13 years). Pre-operative WOMAC total and WOMAC subscores showed no significant differences between groups. Post-operatively, the WOMAC total was significantly better in Group 1 than in Group 2, 10 ± 22 and 19 ± 31, respectively (p < 0.001, Power 97.5%). Similarly, the WOMAC subscores for pain, stiffness, and function were also significantly better in Group 1 than in Group 2. Five-year prosthesis survival was 94.2 and 91.6% in Groups 1 and 2, respectively (p = 0.07, Power 71%).DiscussionPatients with pre-operative complete joint space collapse (0 to 1 mm mJSW) achieve a significantly better WOMAC result from TKA than do those with a mJSW equal to or greater than 2 mm. From our findings, it is recommended that “complete joint space collapse” especially be used as an indication for TKA surgery.ConclusionOur study was underpowered to sufficiently show an effect of pre-operative mJSW on prosthesis survival.