Differences In Joint Space Width Research Articles

Valgus stress radiographs have a minor additional value in detecting lateral cartilage wear when selecting patients for medial partial knee replacement.

A valgus stress radiograph, in addition to the weight-bearing fixed flexion posteroanterior radiograph (e.g., Rosenberg), is deemed useful to assess lateral cartilage wear by measuring lateral joint space width (JSW) in patients with medial knee osteoarthritis. This study aimed to assess: (1) the difference in measured lateral JSW between the Rosenberg and the valgus stress radiograph, and (2) the ability of the valgus stress radiograph to detect lateral cartilage wear (indicated by joint space narrowing) in patients where the Rosenberg radiograph showed full thickness cartilage (i.e., the additional value). The Rosenberg and valgus stress radiographs, obtained between January 1st 2018 and December 31st 2018, of 137 patients with medial knee osteoarthritis prior to total or partial knee replacement were retrospectively collected. The lateral JSW was measured at its midpoint (midJSW) and minimum (minJSW). The differences were tested with a paired-sample t test. The valgus stress radiograph was considered to have an additional value if: (1) JSW ≥ 5mm on the Rosenberg radiograph, (2) JSW < 5mm on valgus stress radiograph, and (3) > 2mm less JSW on the valgus stress than on the Rosenberg radiograph. The mean differences in lateral JSW between the Rosenberg and valgus stress radiographs were 0.53mm (SD = 1.0mm, p < 0.001) for midJSW and 0.66mm (SD = 1.1mm, p < 0.001) for minJSW with both values being lower on the valgus stress radiograph. The valgus stress radiograph was of additional value in 4-6% of the patients. Although the valgus stress radiograph shows more lateral JSW narrowing compared to Rosenberg radiograph, it only has an additional value in 1 out of 17-25 patients with medial osteoarthritis. We, therefore, recommend a Rosenberg radiograph as routine radiographic assessment and only use an additional valgus stress radiograph in case of discrepancy between clinical and radiological findings.

Poster 216: Comparison of Joint Space Narrowing to the Contralateral Side During Hip Arthroscopy: Predictor of Conversion to THA?

Objectives: Reduced joint space at the time of joint-preserving hip arthroscopy has been shown to be correlated with rates of eventual conversion to total hip arthroplasty (THA). With an increasingly aging population and increased utilization of hip arthroscopy, it is important to identify factors that may predict early failure and the eventual need for arthroplasty. For some patients, hip arthroscopy may provide symptomatic relief for years, while others garner limited benefit and require conversion THA soon after their index surgery. This study sought to determine if quantitative differences in joint space width (JSW) between the operative and non-operative hip predicted the likelihood of conversion to THA at the time of hip arthroscopy. Methods: After obtaining institutional review board approval, a retrospective review identified 105 patients treated for labral tears with arthroscopic hip surgery by a single-surgeon with a minimum of 5- year follow-up. Patients were stratified into cohorts based on whether they received a subsequent THA. Preoperative, anteroposterior pelvic radiographs were obtained for each patient and semi-automated, quantitative JSW measurements were performed at 3 predefined fixed locations per hip (10, 30, and 50 degrees with respect to a polar coordinate system; Figure 1). All measurements were obtained by an independent assessor blinded to other radiographic or clinical information, with high reliability (intra- class correlations &gt; 0.8), as previously described in literature. Differences in JSW at each prefixed angle were calculated by subtracting the width (millimeters) of each patient’s operative hip from the measurements obtained from their non-operative hip. Categorical variables were analyzed using chi- square test or Fisher exact test, as appropriate. After assessing for normality with Shapiro-Wilk tests, continuous variables were compared using Student t-tests or Mann-Whitney U tests to determine baseline differences between patients that converted to THA and those that did not. Logistic regression was run for JSW at each prefixed angle, followed by adjusted, multivariable logistic regression to determine independent predictors of conversion to THA. Results: Mean [standard deviation (SD)] follow-up was 8.81 [2.68] years, identifying 16 (15.2%) patients that converted to THA and 89 (84.8%) that did not. When comparing baseline demographic and intraoperative characteristics between cohorts, THA patients were found to have higher mean [SD] age 41.8 [13.4; p=0.003], BMI 29.3 [4.2; p&lt;0.001], Tönnis grade (p&lt;0.001), Outerbridge grade (p=0.002) and higher percentage of males (p=0.014; Tables 1&amp;2). THA patients were found to have a significantly greater difference in JSW at 30° compared to those that did not require subsequent hip arthroplasty (0.566 ± 0.883mm versus 0.038 ± 0.499mm, p=0.035). Differences in JSW between cohorts were not significant at the 10° (p=0.104) or 50° (p=0.096) locations. When adjusting for significantly different covariates, the difference in JSW at 30° was correlated with an increased likelihood of conversion to THA (Adjusted Odds Ratio [AOR]: 4.00; 95% Confidence Interval [CI]: 1.06 to 15.13; p =0.041). Finally, adjusted analysis controlling for differences in JSW at all predefined angles found that narrowing at 30° was significantly associated with increased odds of conversion ([AOR]: 3.88; [CI]: 1.06 to 14.22; p=0.041), while 10° (p=0.630) and 50° (p=0.995) were not. Conclusions: To best educate patients on the risk of THA following hip arthroscopy, identifying objective predictors of early failure is imperative during preoperative evaluation. This study identified that differences in JSW at 30° between the operative and non-operative hip were significantly associated with increased risk of conversion after controlling for demographic and intraoperative factors. Analysis was limited by predetermined locations for JSW and future studies may identify stronger correlations by incorporating additional measurements within the acetabular sourcil. Quantitative differences in JSW comparing the operative hip to the contralateral side predicts patients progressing to THA at the time of hip arthroscopy. [Table: see text] [Table: see text]

Quantification of joint space width with different grades of manual traction in patients with adhesive capsulitis-A fluoroscopic study

Adhesive capsulitis causes adaptive shortening of the non-contractile structures around the shoulder joint which may affect the distraction distance or joint space width (JSW) between the glenoid and humeral head. Joint traction is a commonly used manual therapy technique to reduce pain and gain range of motion in patients with adhesive capsulitis. However, changes in JSW with manual traction are not objectively assessed. This study aimed to find differences in shoulder JSW with different grades of traction and made comparisons between the affected and the unaffected side using 2D fluoroscopy. Forty-one subjects (24 males, 17 females; age 53.9±7.9 years) diagnosed with adhesive capsulitis with low to moderate joint irritability were included. Their mean duration of symptoms was 5.25±1.7 months. True anteroposterior view images of the shoulder were taken with the patient in a supine position with their arms held at 75° of abduction. Images of the affected and unaffected side were taken while no traction, grade 2 and grade 3 manual traction were applied. The JSW was determined as the linear distance between the articular surfaces. Repeated measures ANOVA with post hoc testing was used for analysing differences across the sides (affected and unaffected side) and conditions (No, grade 2 and grade 3 traction). There was no significant interaction between conditions and sides (P=0.99). Averaged across sides, the JSW with grade 2 or 3 traction was 0.18 and 0.23 mm more than the no traction condition (P=0.013 and P=0.001, respectively). There were no differences in the JSW with grade 2 or 3 traction. Averaged across the conditions, the JSW on the unaffected side was 0.21 mm more than the affected side (P=0.03). The study demonstrates that adhesive capsulitis causes a reduction in JSW at 75° abducted position and grade 2 or 3 manual traction can significantly increase this JSW. Clinical Trial Registry India: CTRI/2018/12/016657.

WEIGHT BEARING 3-D JOINT SPACE WIDTH DISTRIBUTION AT THE KNEE VARIES ACCORDING TO LOCATION AND EXTENT OF MENISCAL EXTRUSION: A MOST INVESTIGATION

Quantitative 3-D measurement of joint space width (JSW) from weight bearing computed tomography (WBCT) allows analysis of knee tibiofemoral compartments in a loaded stance without subregional constraints on analysis. The relationship between 3-D JSW distribution and meniscal extrusion is yet to be established. To demonstrate topographic variations in 3-D JSW distribution at the knee derived from WBCT imaging data according to meniscal extrusion location and extent. WBCT knee imaging was acquired at the 144-month visit of the Multicenter Osteoarthritis Study (MOST). A subset of individuals had medial and lateral meniscal extrusion grading according to the MRI Osteoarthritis Knee Score to identify medial extrusion of the medial meniscus (MMmed), anterior extrusion of the medial meniscus (MMant), anterior extrusion of the lateral meniscus (LMant), and lateral extrusion of the lateral meniscus (LMlat). The extent of extrusion was graded as 0: <2 mm; 1: 2 to 2.9 mm, 2: 3 to 4.9 mm; and 3: >5 mm. After semi-automatic segmentation of 663 baseline knees, joint space mapping was performed to create 3-D JSW maps for each knee registered to a template surface. Statistical parametric mapping (SPM) was performed using a general linear model to test the dependence of 3-D JSW distribution on each of meniscal extrusion type in turn. SPM results were plotted on the canonical joint surface, with unmasked regions demonstrating the topographic difference in JSW for each increment in extrusion score. 568 knees from 330 participants had meniscal extrusion grading available. Participants (178 female) had mean ± SD age 62.0 ± 9.3 years, body mass 82.2 ± 17.4 kg, height 170 ± 9.5 cm, and BMI 28.3 ± 4.8 kg/m2. Analysed knees were bilateral for 238 participants and unilateral for 92 participants. For MMmed (cohort score range 0-3), the central-to-posterior medial compartment had significantly lower JSW by up to 0.4 mm for each increment in meniscal extrusion grade. Both MMmed and MMant (score range 0-3) were associated with a small region of similarly significantly lower JSW along the medial margin of the lateral compartment, but also with significantly greater JSW at the anterior medial compartment of up to 0.6 mm per grade. The posterior medial joint space was significantly narrower (up to 3 mm) comparing knees with LMant scores of 0 vs 1. This same magnitude of narrowed JSW was detected along the periphery of the lateral joint space comparing grades in the lateral tibiofemoral compartment, but this was not statistically significant. LMlat (score range 0-2) was associated with a trend for greater reduction in JSW in the central lateral compartment of up to 0.5 mm per grade, but this was not statistically significant. Direction of meniscal extrusion is represented by the black arrowhead in the figure. Both medial and anterior extrusion of the medial meniscus are associated with significant reduction in JSW at the medial margin of the lateral joint space and widening of the anterior margin, likely from a posteromedial shift of the femoral condyles with respect to the tibia. Medial extrusion of the medial meniscus is also associated with narrowed JSW in the central to posterior medial joint space, likely as a direct effect of the loss of meniscal hoop tension. Anterior (but not lateral) extrusion of the lateral meniscus is associated with significantly lower JSW in the posterior medial joint space. These findings confirm that the extent and location of meniscal extrusion are key factors in weight bearing 3-D JSW distribution.

Comparison of Radiologic Results after Lateral Meniscal Allograft Transplantation with or without Capsulodesis Using an All-Soft Suture Anchor.

Background and Objectives: Studies analyzing magnetic resonance imaging (MRI) after simultaneously performing lateral meniscal allograft transplantation (MAT) and capsulodesis are currently rare. This study aimed to compare the MRI results between the group that performed lateral MAT alone and the group that performed both lateral MAT and capsulodesis simultaneously. Materials and Methods: A total of 55 patients who underwent lateral MAT with a 1-year follow-up MRI were included. The patients were divided into two groups according to the surgical procedure: group I (isolated lateral MAT, n = 26) and group C (combined lateral MAT and capsulodesis, n = 29). Differences between groups were compared regarding subjective knee scores, graft extrusion, graft signal, articular cartilage loss, and joint space width (JSW). Results: The subjective knee scores improved significantly in both groups (all, p < 0.001), and there were no significant differences in these scores between both groups at the 1-year follow-up. Group C showed less coronal graft extrusion at the 1-year follow-up (1.1 ± 1.7 mm vs. 2.4 ± 1.8 mm, p < 0.001). Pathologic coronal graft extrusion (≥3 mm) was found in seven (26.9%) patients in group I and three (10.3%) in group C. Concerning the graft signal, group C showed less grade 3 signal intensity in the posterior root of the graft. There were no significant differences in preoperative and postoperative cartilage status between groups. Regarding JSW, there were no significant differences in postoperative JSW between both groups. However, in group C, JSW significantly increased from 3.9 ± 0.4 mm to 4.5 ± 1.4 mm (p = 0.031). Conclusions: In lateral MAT, capsulodesis (open decortication and suture anchor fixation) could reduce graft extrusion without complications. In the future, large-volume and long-term prospective comparative studies are needed to confirm the clinical effects following capsulodesis.

RADIOLOGICAL ASSESSMENT OF KNEE JOINT WIDTH DIFFERENCES IN OLDER ADULTS WITH SYMPTOMATIC MEDIAL KNEE OSTEOARTHRITIS

Knee osteoarthritis (OA) is a degenerative articular disease. The knee joint space width (JSW) is used for grading the severity of knee OA. However, there is a lack of research on differences in the widths of knee joints between both lower limbs in unilateral OA. The purpose of this research was to examine the radiological difference in the affected knee joint and contralateral knee joint by analyzing unilateral older adults with medial knee OA using both knees’ JSW differences. Twenty-five subjects with unilateral medial knee OA participated. X-ray radiographs were used to assess knee JSW, and the paired [Formula: see text]-test was performed to assess the knee joint gap width between the affected side and the unaffected side in the respective medial and lateral sides. The independent [Formula: see text]-test compared the differences between the lateral and medial knee JSWs on the affected side and unaffected side. The paired [Formula: see text]-test did not show a significant difference in the medial and lateral knee JSW on the affected side compared to the unaffected side ([Formula: see text]; 0.11). Meanwhile, the independent [Formula: see text]-test revealed a significant difference between the affected and unaffected sides ([Formula: see text]). This study showed no significant changes in affected knee JSWs compared to unaffected sides, but the difference between the lateral and medial JSWs was significant between the knees affected and unaffected by OA in the older adults with medial knee OA.

Quantitative Three-dimensional Assessment of Knee Joint Space Width from Weight-bearing CT.

Background Imaging of structural disease in osteoarthritis has traditionally relied on MRI and radiography. Joint space mapping (JSM) can be used to quantitatively map joint space width (JSW) in three dimensions from CT images. Purpose To demonstrate the reproducibility, repeatability, and feasibility of JSM of the knee using weight-bearing CT images. Materials and Methods Two convenience samples of weight-bearing CT images of left and right knees with radiographic Kellgren-Lawrence grades (KLGs) less than or equal to 2 were acquired from 2014 to 2018 and were analyzed retrospectively with JSM to deliver three-dimensional JSW maps. For reproducibility, images of three sets of knees were used for novice training, and then the JSM output was compared against an expert's assessment. JSM was also performed on 2-week follow-up images in the second cohort, yielding three-dimensional JSW difference maps for repeatability. Statistical parametric mapping was performed on all knee imaging data (KLG, 0-4) to show the feasibility of a surface-based analysis in three dimensions. Results Reproducibility (in 20 individuals; mean age, 58 years ± 7 [standard deviation]; mean body mass index, 28 kg/m2 ± 6; 14 women) and repeatability (in nine individuals; mean age, 53 years ± 6; mean body mass index, 26 kg/m2 ± 4; seven women) reached their lowest performance at a smallest detectable difference less than ±0.1 mm in the central medial tibiofemoral joint space for individuals without radiographically demonstrated disease. The average root mean square coefficient of variation was less than 5% across all groups. Statistical parametric mapping (33 individuals; mean age, 57 years ± 7; mean body mass index, 27 kg/m2 ± 6; 23 women) showed that the central-to-posterior medial joint space was significantly narrower by 0.5 mm for each incremental increase in the KLG (threshold P < .05). One knee (KLG, 2) demonstrated a baseline versus 24-month change in its three-dimensional JSW distribution that was beyond the smallest detectable difference across the lateral joint space. Conclusion Joint space mapping of the knee using weight-bearing CT images is feasible, demonstrating a relationship between the three-dimensional joint space width distribution and structural joint disease. It is reliably learned by novice users, can be personalized for disease phenotypes, and can be used to achieve a smallest detectable difference that is at least 50% smaller than that reported to be achieved at the highest performance level in radiography. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Roemer in this issue.

Meniscal Deficiency Period and High Body Mass Index Are Preoperative Risk Factors for Joint Space Narrowing After Meniscal Allograft Transplantation

Background: Several studies have reported further reduction in joint space width (JSW) after meniscal allograft transplantation; some contributing postoperative factors are known, although preoperative factors remain unclear. This study is the first to analyze the preoperative risk factors for reduced JSW in patients after lateral meniscal allograft transplantation (LMAT). Hypothesis: Poor cartilage status and high preoperative body mass index (BMI) influence the postoperative progression of joint space narrowing. Study Design: Case-control study; Level of evidence, 3. Methods: We retrospectively studied 79 patients after LMAT who were observed for at least 5 years. JSWs on weightbearing flexion posteroanterior radiographs were measured preoperatively and at the 5-year mark. Differences in JSW were divided into more progression and less progression groups. The modified Outerbridge cartilage grades based on magnetic resonance imaging assessments were compared at subtotal/total meniscectomy and at LMAT to determine the difference between time points. Preoperative between-group differences in sex, age, surgical side, follow-up period, weight, height, BMI, and meniscal deficiency period were analyzed. Clinical outcomes were evaluated using the Lysholm score. Data were examined using univariate and multivariate logistic regressions. Results: Radiographically, the overall change in JSW from preoperative to follow-up was 0.58 mm (range, –0.23 to 1.83 mm). Reductions in JSW in the more progression and less progression groups were 0.94 ± 0.32 and 0.22 ± 0.21 mm (mean ± SD), respectively. There was no difference in cartilage status between the groups at meniscectomy or LMAT; however, changes between time points were significant on the lateral femoral condyle and lateral tibial plateau. Clinically, there were significant differences in weight, BMI, and meniscal deficiency period between the 2 groups. Postoperative Lysholm scores increased as compared with the preoperative scores, but there was no difference among the postoperative time points. In the univariate logistic regression risk analysis, weight, BMI, meniscal deficiency period, and the difference in cartilage status between time points for the lateral femoral condyle and lateral tibial plateau were identified as significant. In the subsequent multivariate logistic regression, BMI (odds ratio, 1.45; P = .016) and meniscal deficiency period (odds ratio, 1.21; P = .037) were the statistically significant factors. Conclusion: BMI and meniscal deficiency period were preoperative risk factors for JSW narrowing after LMAT. This suggests that the meniscal deficiency period from meniscectomy to LMAT may be shortened and that proper weight management can lead to successful LMAT.

Quantification of Joint Space Width Difference on Radiography Via Phase-Only Correlation (POC) Analysis: a Phantom Study Comparing with Various Tomographical Modalities Using Conventional Margin-Contouring.

Several visual scoring methods are currently used to assess progression of rheumatoid arthritis (RA) on radiography. However, they are limited by its subjectivity and insufficient sensitivity. We have developed an original measurement system which uses a technique called phase-only correlation (POC). The purpose of this study is to validate the system by using a phantom simulating the joint of RA patients.A micrometer measurement apparatus that can adjust arbitrary joint space width (JSW) in a phantom joint was developed to define true JSW. The phantom was scanned with radiography, 320 multi detector CT (MDCT), high-resolution peripheral quantitative CT (HR-pQCT), cone beam CT (CBCT), and tomosynthesis. The width was adjusted to the average size of a women's metacarpophalangeal joint, from 1.2 to 2.2mm with increments of 0.1mm and 0.01mm. Radiographical images were analyzed by the POC-based system and manual method, and images from various tomographical modalities were measured via the automatic margin detection method. Correlation coefficients between true JSW difference and measured JSW difference were all strong at 0.1mm intervals with radiography (POC-based system and manual method), CBCT, 320MDCT, HR-pQCT, and tomosynthesis. At 0.01mm intervals, radiography (POC-based system), 320MDCT, and HR-pQCT had strong correlations, while radiography (manual method) and CBCT had low correlations, and tomosynthesis had no statistically significant correlation. The smallest detectable changes for radiography (POC-based system), radiography (manual method), 320MDCT, HR-pQCT, CBCT, and tomosynthesis were 0.020mm, 0.041mm, 0.076mm, 0.077mm, 0.057mm, and 0.087mm, respectively. We conclude that radiography analyzed with the POC-based system might sensitively detect minute joint space changes of the finger joint.

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

The change of joint space width after medial open wedge high tibial osteotomy

Purpose: After medial open wedge high tibial osteotomy (MOWHTO), an increase in the joint space width(JSW) of the medial compartment of the knee joint is commonly observed in clinical practice. Since the JSW is regarded as a surrogate measure for cartilage thickness, it has been suggested that the increment of the medial JSW observed after MOWHTO would have resulted from the cartilage regeneration. However, the association between the change of medial JSW after MOWHTO and cartilage regeneration has not investigated with the second-look arthroscopic examination, which could provide an actual status of the cartilage status. Moreover, the possibility that change in JSW is due to the shift of the weight-bearing axis of the lower limb cannot be excluded. The aim of the present study was to investigate the relevant factors that affect the change of JSW after MOWHTO. It was hypothesized that the change of JSW after MOWHTO would be associated with the change of the weight-bearing condition. Methods: A total of 100 patients who underwent MOWHTO and a following second-look arthroscopic assessment were included in this study. The patients were classified into two groups according to the change of medial JSW between at the time of primary operation(MOWHTO) and at the time of second-look operation: group 1(the patients with increased medial JSW) and group 2 (the patients with maintained or reduced medial JSW). Comparative analysis was performed regarding clinical scores, radiographic parameters, and arthroscopic measurements between the two groups. In addition, for the statistically significant variables, the characteristics of JSW of the knee were further evaluated. Results: There were no differences between the two groups in the preoperative clinical scores as well as the postoperative clinical scores evaluated at the time of second-look operation. Furthermore, there were no significant differences between the two groups regarding the change of cartilage lesion size between the two-time points as well as the cartilage regeneration status. However, the postoperative load-axis deviation and the postoperative medial proximal tibial angle were significantly higher in group 1, suggesting that the increase in medial JSW is possibly related to the postoperative weight-bearing condition. Accordingly, an additional analysis was performed to evaluate whether there were differences in JSW characteristics (medial JSW, lateral JSW, and joint-line convergence angle) according to the position of the postoperative load-axis deviation. The patients were further divided into three groups (group U, under-correction group; group A; acceptable correction group; group O; over-correction group). As a result, there was a statistically significant difference in the postoperative medial JSW and the degree of change in medial JSW, in which the medial JSW increased as the postoperative load-axis deviation located laterally. Medial JSW increased over time in group A and O, whereas it showed a tendency to decrease in group U. On the contrary, there were no differences in lateral JSW and joint-line convergence angle between the groups. Conclusions: The increase in the medial JSW observed after MOWHTO was affected by the postoperative weight-bearing condition, rather than the cartilage regeneration status. Therefore, changes in JSW observed after MOWHTO should not be used as a surrogate measure for cartilage thickness. In addition, for a clinical perspective, it could be recommended to aim the post-operative weight-bearing line to be located at 60-70% of the tibial articular surface from the medial border of the tibia, considering postoperative medial JSW as well as other biomechanical aspects of the knee.

Detection of Fine Radiographic Progression in Finger Joint Space Narrowing Beyond Human Eyes: Phantom Experiment and Clinical Study with Rheumatoid Arthritis Patients

The visual assessment of joint space narrowing (JSN) on radiographs of rheumatoid arthritis (RA) patients such as the Genant-modified Sharp score (GSS) is widely accepted but limited by its subjectivity and insufficient sensitivity. We developed a software application which can assess JSN quantitatively using a temporal subtraction technique for radiographs, in which the chronological change in JSN between two radiographs was defined as the joint space difference index (JSDI). The aim of this study is to prove the superiority of the software in terms of detecting fine radiographic progression in finger JSN over human observers. A micrometer measurement apparatus that can adjust arbitrary joint space width (JSW) in a phantom joint was developed to define true JSW. We compared the smallest detectable changes in JSW between the JSDI and visual assessment using phantom images. In a clinical study, 222 finger joints without interval score change on GSS in 15 RA patients were examined. We compared the JSDI between joints with and without synovial vascularity (SV) on power Doppler ultrasonography during the follow-up period. True JSW difference was correlated with JSDI for JSW differences ranging from 0.10 to 1.00 mm at increments of 0.10 mm (R2 = 0.986 and P < 0.001). Rheumatologists were difficult to detect JSW difference of 0.30 mm or less. The JSDI of finger joints with SV was significantly higher than those without SV (P = 0.030). The software can detect fine differences in JSW that are visually unrecognizable.

Long-term Outcomes of Meniscal Allograft Transplantation With and Without Extrusion: Mean 12.3-Year Follow-up Study

Background: Meniscal allograft transplantation (MAT) is a widely performed surgical technique used to reconstruct meniscal deficiencies after meniscectomy. However, the long-term effects of extrusion on clinical and radiologic outcomes are unclear. Hypothesis: In long-term follow-up, extrusion after MAT would show poorer outcomes than nonextrusion and would lead to faster progression of arthritic changes. Study Design: Cohort study; Level of evidence, 3. Methods: Forty-five MAT cases (lateral, n = 36; medial meniscal, n = 9) with a minimum 8-year follow-up period were selected. The mean follow-up period was 12.3 years (range, 8.0-19.6 years). Data were collected on patients’ sex, age, surgical side, and mechanical axis deviation. Patients were categorized into 2 groups: extrusion (≥3 mm) and nonextrusion (<3 mm). Categories were based on extrusion length measured via magnetic resonance imaging taken 1 year after surgery. Joint space width (JSW) on the affected and contralateral sides was measured on bilateral weightbearing posterior-anterior radiographs at 45° of flexion at 3 time points (preoperative, 4-6 years postoperative, and >8 years postoperative). Differences of the measured and relative JSW values between the groups and differences at different time points were analyzed. The Lysholm score was used to evaluate clinical function. Results: Mean ± SD extrusion was 3.07 ± 0.82 mm. The extrusion and nonextrusion groups were composed of 19 (42.2%) and 26 (57.8%) patients, respectively. Analysis of JSW showed a difference in relative JSW between the groups at >8 years (P = .017). At the point of transition from 4 to 6 years to >8 years, the differences in absolute JSW values were −1.25 ± 0.78 mm (extrusion group) and −0.58 ± 0.66 mm (nonextrusion group; P < .001). Relative JSW values also differed between groups (extrusion group, −0.22 ± 0.13; nonextrusion group, −0.04 ± 0.18; P < .001). No differences were observed in the Lysholm scores between the groups at each time point. Conclusion: Long-term follow-up after MAT revealed a greater decrease in JSW in the extrusion group than in the nonextrusion group. However, no significant differences in clinical outcomes were observed.

Standardizing the Prearthritic Hip Joint Space Width: An Analysis of 994 Hips

The purposes of this study were (1) to define a normal prearthritic hip joint space width (JSW) in symptomatic and asymptomatic patients with various degrees of acetabular coverage based on the lateral center edge angle (LCEA) and (2) to determine predictors of JSW using patient-specific variables. In a consecutive series of patients presenting to a hip preservation clinic between July 2012 and April 2016, a standard weight-bearing anteroposterior pelvic view was obtained. JSW was defined as the distance between the bony contour of the acetabular rim and femoral head in 2 locations (lateral and medial weight-bearing zone). Hips with severe anatomic deformity, a Tönnis grade >0, or a lateral or medial JSW <2.5mm were excluded. A linear mixed model analysis was performed in order to determine which variables (age, sex, side, height, weight, symptomatic/asymptomatic, LCEA, and clinical diagnosis) were significantly related to JSW. A total of 994 hips were included. LCEA was found to be a significant predictor of both the lateral and medial JSW, with a decreased JSW associated with increasing degrees of acetabular bony coverage (P < .02). A mean 0.9mm (20%) difference in medial JSW was found between patients with frank dysplasia (LCEA <20°) compared with those with pincer-type FAI (LCEA ≥40°). There was no difference between symptomatic and asymptomatic hips, either for lateral (asymptomatic: 4.51 ± 0.83mm; symptomatic: 4.52 ± 0.85mm; P= .58) or medial JSW (asymptomatic: 4.02±0.96mm; symptomatic: 3.97 ± 0.84mm; P= .49). The LCEA is a significant predictor of hip JSW, with the mean JSW decreasing with increasing degrees of acetabular bony coverage. Joint space is not a major factor in symptomatology in adults with prearthritic hip pain. Level III, retrospective comparative study.

Preoperative KOOS and SF-36 Scores Are Associated With the Development of Symptomatic Knee Osteoarthritis at 7 Years After Anterior Cruciate Ligament Reconstruction

Background: Anterior cruciate ligament (ACL) tears are associated with the development of knee osteoarthritis despite ACL reconstruction surgery. However, little evidence is available to determine which patients will develop symptomatic knee osteoarthritis. Purpose: To determine if preoperative outcome measures—KOOS (Knee injury and Osteoarthritis Outcome Score) and SF-36 (36-item Short Form Health Survey)—were associated with the development of a symptomatic knee 7 years after ACL reconstruction. A secondary goal was to examine the relationship between imaging evidence of knee osteoarthritis and development of knee pain. Study Design: Case-control study; Level of evidence, 3. Methods: Prospectively collected data from 72 patients were reviewed with 7-year follow-up after unilateral ACL reconstruction. Patients were divided into symptomatic and asymptomatic groups based on the previously defined KOOS pain ≤72. Demographic variables and preoperative KOOS and SF-36 scores were compared between groups. Radiographic and magnetic resonance imaging data were used to evaluate differences in joint space width, Osteoarthritis Research Society International radiographic score, and the Whole-Organ Magnetic Resonance Imaging Score between groups. Univariate and multivariate analyses were performed to identify potential predictors of pain at 7-year follow-up. Wilcoxon sum rank and t tests were used to compare imaging findings between the symptomatic and asymptomatic patients at 7 years. Results: According to KOOS pain, 7 of the 72 patients available at 7-year follow-up formed the symptomatic group. No differences were found between groups in regard to demographic variables or intraoperative findings. In multivariate analysis, lower preoperative scores for KOOS sports/recreation (P = .005) and SF-36 mental health (P = .025) were associated with a painful knee at 7 years, with increased odds of 82% and 68% per 10-unit decrease, respectively. The Whole-Organ Magnetic Resonance Imaging Score at 7 years showed evidence of osteoarthritic changes in the symptomatic group as compared with the asymptomatic group (P = .047). However, there were no significant differences in the Osteoarthritis Research Society International radiographic score (P = .051) or joint space width (P = .488) between groups. Conclusion: Lower preoperative KOOS and SF-36 scores were associated with those patients who developed symptomatic knee osteoarthritis 7 years after ACL reconstruction.

Fully automated joint space width measurement and digital X-ray radiogrammetry in early RA

ObjectivesTo study fully automated digital joint space width (JSW) and bone mineral density (BMD) in relation to a conventional radiographic scoring method in early rheumatoid arthritis (eRA).MethodsRadiographs scored by the...

Diagnostic performance of bilateral false profile radiographs in early hip osteoarthritis

Objectives1. To show that the anterior hip joint space is profiled only on the contralateral false profile radiograph. 2. To provide normal values of hip joint space width on anteroposterior and false profile radiographs. 3. To identify the best sites for joint space radiographic measurements to depict early hip osteoarthritis. MethodsAnteroposterior and bilateral false profile radiographs of a cadaveric pelvis with markers around the anterior part of the hip joint were obtained. Joint space width was measured at ten sites on anteroposterior pelvis and bilateral hip false profile radiographs in 37 patients without hip pain (mean age, 59 years) and 65 patients with hip pain (mean age, 57.5 years), including 30 with and 35 without radiographic osteoarthritic subchondral bone changes. Between-groups differences in joint space width at each site were evaluated using ANOVA. The ability of joint space width at each site to discriminate between patients groups was investigated using logistic regression. ResultsThe anterior joint space was only profiled on a contralateral false profile radiograph. Presumably, normal joint space widths were obtained in the group without hip pain. Joint space widths measured on the false profile radiographs differed significantly between the patient groups while measurements on the anteroposterior pelvis radiograph did not. ConclusionsBilateral false profile radiographs profile the entire hip joint space, including its anterior part, and discriminate better between patients with and without hip pain than the anteroposterior pelvis radiograph. The AS/P joint space width ratio (anterosuperior/posterior) was the best parameter.

Validation of automatic joint space width measurements in hand radiographs in rheumatoid arthritis.

Computerized methods promise quick, objective, and sensitive tools to quantify progression of radiological damage in rheumatoid arthritis (RA). Measurement of joint space width (JSW) in finger and wrist joints with these systems performed comparable to the Sharp-van der Heijde score (SHS). A next step toward clinical use, validation of precision and accuracy in hand joints with minimal damage, is described with a close scrutiny of sources of error. A recently developed system to measure metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints was validated in consecutive hand images of RA patients. To assess the impact of image acquisition, measurements on radiographs from a multicenter trial and from a recent prospective cohort in a single hospital were compared. Precision of the system was tested by comparing the joint space in mm in pairs of subsequent images with a short interval without progression of SHS. In case of incorrect measurements, the source of error was analyzed with a review by human experts. Accuracy was assessed by comparison with reported measurements with other systems. In the two series of radiographs, the system could automatically locate and measure 1003/1088 (92.2%) and 1143/1200 (95.3%) individual joints, respectively. In joints with a normal SHS, the average (SD) size of MCP joints was [Formula: see text] and [Formula: see text] in the two series of radiographs, and of PIP joints [Formula: see text] and [Formula: see text]. The difference in JSW between two serial radiographs with an interval of 6 to 12 months and unchanged SHS was [Formula: see text], indicating very good precision. Errors occurred more often in radiographs from the multicenter cohort than in a more recent series from a single hospital. Detailed analysis of the 55/1125 (4.9%) measurements that had a discrepant paired measurement revealed that variation in the process of image acquisition (exposure in 15% and repositioning in 57%) was a more frequent source of error than incorrect delineation by the software (25%). Various steps in the validation of an automated measurement system for JSW of MCP and PIP joints are described. The use of serial radiographs from different sources, with a short interval and limited damage, is helpful to detect sources of error. Image acquisition, in particular repositioning, is a dominant source of error.

Effects of Axial Traction during Direct MR-Arthrography of the Wrist in Sports Injuries.

Purpose:To evaluate the degree of joint distraction during direct MR arthrography with axial traction in sports injuries. To confirm the effect of axial traction on the quality of wrist opacification.Patients and methods:Seventeen patients (11 male, 6 female) underwent wrist MR arthrography without (mean: 39 years (SD 11.6))., and 20 patients (16 male, 4 female) with axial traction (mean: 28 years (SD 7.1)). Subgroups were defined according to pathology: degenerative, ligamentous, traumatic, normal (ie patients without MR-arthrography lesions). Radioscaphoid, radiolunate, lunocapitate, ulna Triangular Fibrocartilage (TFC), scapho-lunate, luno-triquetral, ulnocarpal, Carpo-Metacarpal (CMC) I and III and distal radio-ulnar spaces were measured for all patients. Differences in joint space width were compared between subgroups. Joint space opacification was subjectively scored from 0 (no opacification) to 3 (fully opacified), and compared between the groups with and without traction.Results:The difference in joint space was statistically significant (p<0.05) for radioscaphoid, radiolunate, lunocapitate and ulnocarpal spaces, but only in patients with ligamentous tears. Opacification score was significantly higher for ulnocarpal (p=0.0275) and CMC III joint spaces (p=0.0272) with axial traction.Conclusion:Axial traction resulted in a significantly higher radioscaphoid, radio-lunate, lunocapitate and ulnocarpal joint spaces width. This positive effect of axial traction raises the suspicion of sports ligamentous lesions.

Predictors of Lateral Compartment Joint Space Difference at a Minimum of Two Years after ACL Reconstruction

Objectives:ACL reconstruction effectively restores knee stability and allows a return to athletic activities after ACL injury, but patients are still at higher risk of developing post-traumatic OA. Patient reported outcomes from the Multicenter Orthopaedic Outcomes Network (MOON) prospective longitudinal cohort of over 1500 patients undergoing ACL reconstruction showed no increase in OA symptoms (KOOS subscale) at 2 or 6 years after surgery. Therefore, identification of structural changes of OA that may precede the onset of symptoms is of critical importance for determining risk factors for the initiation and progression of post-traumatic OA in addition to measuring the effectiveness of potential disease-modifying treatments. One structural measure of OA is radiographic joint space width (JSW). We previously demonstrated that meniscus treatment and age predict narrower medial compartment JSW.Methods:335 patients from the MOON cohort (154 males, 181 females, median age 18 years at the time of surgery) were recruited at a minimum of 2 years following surgery for on-site evaluations including bilateral metatarsophalangeal joint (MTP) radiographs to assess JSW. To minimize bias related to pre-existing knee injury or OA, subjects were 35 years or younger, were injured playing a sport, had primary ACL reconstruction without prior meniscus or articular cartilage surgery, did not undergo subsequent ACL revision, and had a surgically normal contralateral knee. Radiographic JSW was measured in the lateral compartment of both knees using a validated semiautomated method. The association of age, sex, BMI, meniscus treatment, and articular cartilage treatment with lateral compartment JSW differences (JSD) between the reconstructed and normal knees was examined using multivariable generalized linear models. The Holm-Bonferroni method was used to account for multiple comparisons.Results:The mean lateral compartment JSW was 7.73 mm and (95% CI 7.61-7.85 mm) for ACL reconstructed knees and 7.82 mm (95% CI 7.71-7.94 mm) for contralateral normal knees, with a mean JSD of 0.10 mm (p<0.01). A miltivariable generalized linear model was constructed which adjusted for age, gender, BMI, and baseline Marx activity level. Predictors of JSD that were statistically significant and predicted narrower JSW on the ACL reconstructed side included partial lateral meniscectomy (p<0.001), Marx activity level less than 16(p=0.002), and higer BMI (p=0.02). Graft source, cartilage injury, sex and lateral compartment articular carilage injury wer not significant. Model results are shown in the table.Conclusion:We found that radiographic lateral compartment JSW differences between reconstructed and normal knees could be detected 2 years after durgery in a cohort of patients with previously uninjured knees who sustained ACL tears and underwent subsequent ACL reconstruction. The model showed that parial lateral meniscectomy, lower Marx activity level, and higher BMI were associated with decreased joint space width. The reason that patients with lower activity levels at baseline have narrower lateral compartment JSW on their ACL reconstructed side is unclear and warrants further study.