Validity of the sonographic longitudinal sagittal image for assessment of the cartilage thickness in the knee osteoarthritis

Impact of treadmill running on distal femoral cartilage thickness: a cross-sectional study of professional athletes and healthy controls

PURPOSE

This present study aimed to assess the impact of treadmill running on distal femoral cartilage thickness.

METHODS

Professional athletes aged 20 to 40 years with a history of treadmill running (minimum 75 min per week for the past three months or more) and age-, sex-, and body mass index (BMI)-matched healthy controls were recruited. Demographics and clinical features of participants were recorded. Athletes were divided into subgroup 1 with less than 12 months of treadmill running and subgroup 2 with 12 months or more of treadmill running. Distal femoral cartilage thicknesses were measured at the midpoints of the right medial condyle (RMC), right intercondylar area (RIA), right lateral condyle (RLC), left medial condyle (LMC), left intercondylar area (LIA), and left lateral condyle (LLC) via ultrasonography.

RESULT

A total of 72 athletes (mean age: 29.6 ± 6.6 years) and 72 controls (mean age: 31.9 ± 6.7 years) were enrolled. Athletes had significantly thinner cartilages in the RLC (2.21 ± 0.38 vs. 2.39 ± 0.31 cm, p = 0.002), LLC (2.28 ± 0.37 vs. 2.46 ± 0.35 cm, p = 0.004), and LMC (2.28 ± 0.42 vs. 2.42 ± 0.36 cm, p = 0.039) compared with the control group. Furthermore, cartilage thickness was significantly thinner in subgroup 2 athletes compared with the control group in the RLC (2.13 ± 0.34 vs. 2.39 ± 0.31 cm, p = 0.001), LLC (2.22 ± 0.31 vs. 2.46 ± 0.35 cm, p = 0.005), and LMC (2.21 ± 0.46 vs. 2.42 ± 0.36 cm, p = 0.027); however, subgroup 1 athletes did not have such differences. There was a weak negative correlation between total months of treadmill running and cartilage thickness in the RLC (r = - 0.0236, p = 0.046) and LLC (r = - 0.0233, p = 0.049). No significant correlation was found between the distal femoral cartilage thickness at different sites and the patients' demographic features, including age, BMI, speed and incline of treadmill running, and minutes of running per session and week (p > 0.05).

CONCLUSION

Compared with healthy controls, professional athletes with a history of long-term high-intensity treadmill running had thinner femoral cartilages. The duration (months) of treadmill running was weakly negatively correlated with distal femoral cartilage thickness. Longitudinal studies with prolonged follow-ups are needed to clarify how treadmill running affects femoral cartilage thickness in athletes.

Cumulative knee adduction moment during jogging causes temporary medial meniscus extrusion in healthy volunteers

PURPOSE

The cumulative knee adduction moment (KAM) is a key parameter evaluated for the prevention of overload knee injuries on the medial compartment. Medial meniscus extrusion (MME), typical in hoop dysfunctions, is a measure for the cumulative mechanical stress in individual knees; however, its correlation with cumulative KAM is unknown. The aim of this study was to investigate the effect of temporary overload stress on MME and its correlation with cumulative KAM.

METHODS

Thirteen healthy asymptomatic volunteers (13 knees) were recruited for a cohort study (mean age, 23.1 ± 3.3 years; males: n = 8). The cumulative KAM was calculated using a three-dimensional motion analysis system, in addition to the number of steps taken while jogging uphill or downhill. MME was evaluated using ultrasound performed in the standing position. The evaluations were performed four times: at baseline (T0), before and after (T1 and T2, respectively) jogging uphill or downhill, and 1 day after (T3) jogging. Additionally, the Δ-value was calculated using the change of meniscus after efforts as the difference in MME between T1 and T2.

RESULTS

The MME in T2 was significantly greater than those in T0 and T1. Conversely, the MME in T3 was significantly lesser than that in T2. No significant difference was found between those in T0 and T1, and T3. ΔMME exhibited a significant positive correlation with the cumulative KAM (r = 0.68, p = 0.01), but not for peak KAM.

CONCLUSION

The temporary reaction of MME observed in ultrasound correlates with the cumulative stress of KAM.

Reliability and Convergent Construct Validity of Quantitative Ultrasound for Synovitis, Meniscal Extrusion, and Osteophyte in Knee Osteoarthritis With MRI

AIMS

To determine: 1) inter-rater reliability of quantitative measurements of ultrasound-detected synovitis, meniscal extrusion, and osteophytes; and 2) construct (convergent) validity via correlations and absolute agreements between ultrasound- and gold-standard magnetic resonance imaging (MRI)-outcomes in knee osteoarthritis.

METHODS

Dynamic ultrasound images for supra-patellar synovitis, meniscal extrusion, and osteophytes were acquired and quantified by a physician operator, musculoskeletal ultrasonographer, and medical student independently. On the same day, 3T MRI images were acquired. Effusion-synovitis, meniscal extrusion, and osteophytes were quantified on sagittal or coronal proton-density-weighted fat-suppressed noncontrast TSE sequences, respectively. Intra-class correlation coefficients (ICCs), Pearson's correlations (r), and Bland-Altman plots were used to analyze inter-rater reliability, and correlations, and agreements between the two imaging modalities.

RESULTS

Eighty-nine participants [48 females (53.9%)] with mean (standard deviation) age of 61.5 ± 6.9 years were included. The inter-rater reliability was excellent for osteophytes (ICC range = 0.90-0.96), meniscal extrusion (ICC range = 0.90-0.93), and synovitis (ICC range = 0.86-0.88). The correlations between ultrasound pathologies and their MRI counterparts were very strong (ICC range = 0.85-0.98) except for lateral meniscal extrusion [0.66 (95% CI, 0.52-0.76)]. Bland-Altman plots showed 0.01, 0.05, 0.10, 0.53, and 0.60 mm larger size in ultrasound medial tibial and medial femoral osteophytes, medial meniscal extrusions, synovitis, and lateral meniscal extrusions with 95% limits of agreements [±0.39, ±0.44, ±0.85, ±0.70, and ±0.90 (SDs)] than MRI measures, respectively. The lines of equality were within 95% CI of the mean differences (bias) only for medial osteophytes and medial meniscal extrusion.

CONCLUSION

The quantitative assessment of synovitis, meniscal extrusion, and osteophytes generally showed excellent inter-rater reliability and strong correlations with MRI-based measurements. Absolute agreement was strong for medial tibiofemoral pathologies.

Current concept of kinematic alignment total knee arthroplasty and its derivatives

The kinematic alignment (KA) approach to total knee arthroplasty (TKA) has recently increased in popularity. Accordingly, a number of derivatives have arisen and have caused confusion. Clarification is therefore needed for a better understanding of KA-TKA. Calipered (or true, pure) KA is performed by cutting the bone parallel to the articular surface, compensating for cartilage wear. In soft-tissue respecting KA, the tibial cutting surface is decided parallel to the femoral cutting surface (or trial component) with in-line traction. These approaches are categorized as unrestricted KA because there is no consideration of leg alignment or component orientation. Restricted KA is an approach where the periarthritic joint surface is replicated within a safe range, due to concerns about extreme alignments that have been considered ‘alignment outliers’ in the neutral mechanical alignment approach. More recently, functional alignment and inverse kinematic alignment have been advocated, where bone cuts are made following intraoperative planning, using intraoperative measurements acquired with computer assistance to fulfill good coordination of soft-tissue balance and alignment. The KA-TKA approach aims to restore the patients’ own harmony of three knee elements (morphology, soft-tissue balance, and alignment) and eventually the patients’ own kinematics. The respective approaches start from different points corresponding to one of the elements, yet each aim for the same goal, although the existing implants and techniques have not yet perfectly fulfilled that goal.

Deep learning-based segmentation of knee MRI for fully automatic subregional morphological assessment of cartilage tissues: Data from the Osteoarthritis Initiative

Morphological changes in knee cartilage subregions are valuable imaging-based biomarkers for understanding progression of osteoarthritis, and they are typically detected from magnetic resonance imaging (MRI). So far, accurate segmentation of cartilage has been done manually. Deep learning approaches show high promise in automating the task; however, they lack clinically relevant evaluation. We introduce a fully automatic method for segmentation and subregional assessment of articular cartilage, and evaluate its predictive power in context of radiographic osteoarthritis progression. Two data sets of 3D double-echo steady-state (DESS) MRI derived from the Osteoarthritis Initiative were used: first, n = 88; second, n = 600, 0-/12-/24-month visits. Our method performed deep learning-based segmentation of knee cartilage tissues, their subregional division via multi-atlas registration, and extraction of subregional volume and thickness. The segmentation model was developed and assessed on the first data set. Subsequently, on the second data set, the morphological measurements from our and the prior methods were analyzed in correlation and agreement, and, eventually, by their discriminative power of radiographic osteoarthritis progression over 12 and 24 months, retrospectively. The segmentation model showed very high correlation (r > 0.934) and agreement (mean difference < 116 mm³ ) in volumetric measurements with the reference segmentations. Comparison of our and manual segmentation methods yielded r = 0.845-0.973 and mean differences = 262-501 mm³ for weight-bearing cartilage volume, and r = 0.770-0.962 and mean differences = 0.513-1.138 mm for subregional cartilage thickness. With regard to osteoarthritis progression, our method found most of the significant associations identified using the manual segmentation method, for both 12- and 24-month subregional cartilage changes. The method may be effectively applied in osteoarthritis progression studies to extract cartilage-related imaging biomarkers.

Ultrasonographic Assessment of Knee Cartilage Thickness in Patients with Ulcerative Colitis: Decreased Femoral Cartilage Thickness May Be an Indicator of Extraintestinal Manifestation in Patients with Mild Activity Ulcerative Colitis

OBJECTIVES

Ulcerative colitis is a systemic inflammatory disease which primarily involves the gut but presented by numerous extraintestinal manifestations. The effect of ulcerative colitis on knee cartilage has not been evaluated up to the present. In the current study, we aimed to investigate the possible relationship between the presence of ulcerative colitis and femoral cartilage thickness.

DESIGN

Sixty-two patients with confirmed diagnosis of ulcerative colitis and 70 healthy controls aged 18 to 50 years referred to the gastroenterology outpatient department between January 2018 and January 2019 participated in this cross-sectional study. The measurements were made by ultrasonography with the patient in a supine position and the knees in complete flexion. Demographic, clinical, endoscopic and laboratory data were collected for all the subjects.

RESULTS

The groups of ulcerative colitis and control group were similar with regard to sex, mean age, weight, height, body mass index, extremity dominancy, and existence of knee pain (P > 0.05). Medial femoral condyles, intercondylar areas, and lateral femoral condyles of both right and left knees had thinner cartilage thickness in ulcerative colitis group than control group (P < 0.001).

CONCLUSION

Knee cartilage was thinner in subjects with mild activity ulcerative colitis than in healthy controls. Decreased knee cartilage thickness may be an indicator of extraintestinal manifestation in patients with mild activity ulcerative colitis. This association between ulcerative colitis and knee cartilage degeneration may be effective in early detection of possible risk factors and potential treatment strategies for both ulcerative colitis and specific subtypes of knee osteoarthritis.

Ultrasonographic Assessment of the Normal Femoral Articular Cartilage of the Knee Joint: Comparison with 3D MRI

Objective

Ultrasonography (US) has a promising role in evaluating the knee joint, but capability to visualize the femoral articular cartilage needs systematic evaluation. We measured the extent of this acoustic window by comparing standardized US images with the corresponding MRI views of the femoral cartilage.

Design

Ten healthy volunteers without knee pathology underwent systematic US and MRI evaluation of both knees. The femoral cartilage was assessed on the oblique transverse axial plane with US and with 3D MRI. The acoustic window on US was compared to the corresponding views of the femoral sulcus and both condyles on MRI. The mean imaging coverage of the femoral cartilage and the cartilage thickness measurements on US and MRI were compared.

Results

Mean imaging coverage of the cartilage of the medial femoral condyle was 66% (range 54%-80%) and on the lateral femoral condyle 37% (range 25%-51%) compared with MRI. Mean cartilage thickness measurement in the femoral sulcus was 3.17 mm with US and 3.61 mm with MRI (14.0% difference). The corresponding measurements in the medial femoral condyle were 1.95 mm with US and 2.35 mm with MRI (21.0% difference), and in the lateral femoral condyle, they were 2.17 mm and 2.73 mm (25.6% difference), respectively.

Conclusion

Two-thirds of the articular cartilage of the medial femoral condyle, and one-third in the lateral femoral condyle, can be assessed with US. The cartilage thickness measurements seem to be underestimated by US. These results show promise for the evaluation of the weight-bearing cartilage of the medial femoral condyle with US.

Ultrasonographic assessment of femoral cartilage thickness in patients with Helicobacter pylori infection

OBJECTIVES

Helicobacter pylori is a major cause of gastritis and a potential trigger of inflammatory disease. The effect of H pylori infection on distal femoral cartilage has yet to be evaluated. The aim of this study was to evaluate femoral cartilage thickness in patients with H pylori infection and to find whether this infection affects femoral cartilage thickness.

METHODS

This cross-sectional study included 199 patients. To measure the thickness of femoral articular cartilage, 99 patients with H pylori infections and 100 with H pylori-negative controls were enrolled into two groups. The measurements were made using linear probe ultrasonography with the patients in supine positions and their knees in maximum flexion. Demographic, clinical, endoscopic and laboratory data were collected for all patients.

RESULTS

Both the right and left femoral condyles had thinner cartilage thickness in the H pylori-positive group than in the H pylori-negative group (P = .016, P = .036). For the intercondylar area and lateral femoral condyles, although the H pylori-positive patients had thinner femoral cartilage thickness than the H pylori-negative individuals for both extremities, this finding was not statistically significant (P > .05).

CONCLUSION

Femoral cartilage was thinner in patients with H pylori than patients without H pylori for right and left medial femoral condyles. This study suggests that H pylori infections may affect femoral cartilage thickness and potentially increase the risk of cartilage degeneration.

Evaluation of distal femoral cartilage by B-mode ultrasonography and shear wave elastography in patients with knee osteoarthritis: a preliminary study

BACKGROUND

Degenerative change in articular cartilage is one of the most important factors in the development of osteoarthritis. Shear wave elastography can be used to identify pathologic cartilage.

PURPOSE

To evaluate distal femoral cartilage by shear wave elastography in patients with symptomatic knee osteoarthritis.

MATERIAL AND METHODS

Twenty patients with bilateral knee osteoarthritis (study group) and 20 volunteers with the same demographic characteristics but without symptomatic knee pain (control group) were included in the study. A total of 80 knee joints of 40 individuals were evaluated. At the medial, intercondylar, and lateral condylar levels distal femoral cartilage thickness was measured by B-mode ultrasonography and stiffness was measured by shear wave elastography.

RESULTS

The medial, intercondylar, and lateral cartilage thickness measurements were similar between the two groups and no statistically significant difference was observed (P = 0.711, P = 0.766, and P = 0.575, respectively). The shear wave velocity values in the medial and intercondylar cartilage were significantly higher in the study group (P = 0.002). Shear wave velocity values measured from lateral cartilage were higher in the study group and the difference between the groups had a borderline statistical significance (P = 0.053).

CONCLUSION

Shear wave elastography seems to be a reliable, non-invasive, and acceptable method for the assessment of pathologic cartilage.

Assessment of knee osteoarthritis by ultrasonography and its association with knee pain

BACKGROUND

Pain is a significant cause of disability in knee osteoarthritis. Conventional radiography is widely used in the assessment of knee osteoarthritis, however radiographic findings do not correlate well with pain. Ultrasonography can be used to evaluate the soft tissue structures of the knee that can be related to pain.

OBJECTIVE

To evaluate pain-related soft tissue structures of the knee with ultrasonography.

METHODS

This cross-sectional study included a total of 198 knees from 99 patients with knee osteoarthritis. Knee pain and functional status were evaluated by performing visual analogue scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). On the ultrasound, cartilaginous thickness, knee effusion and presence of Baker's cyst were assessed and the correlation to pain was investigated.

RESULTS

Baker's cyst was significantly more frequent in symptomatic knees (13.9%) compared to asymptomatic knees (2.5%). Patients with Baker's cyst had a significantly more limited degree of knee flexion, significantly higher resting VAS pain scores and worse WOMAC scores compared to patients without Baker's cyst. In log-linear analysis, presence of Baker's cyst increased the risk of pain by 2.94 times.

CONCLUSION

Ultrasound as a modality that is easily accessible, inexpensive and without radiation exposure is helpful to demonstrate factors related to pain in knee osteoarthritis by allowing assessment of soft tissue structures.

Ultrasound measurement of femoral cartilage thickness in the knee of healthy young university students

BACKGROUND AND OBJECTIVE

Articular cartilage (AC) is always affected in any joint with osteoarthritis. Ultrasound can be a useful tool in monitoring changes in the AC. The purpose of the present study is to ultrasound measure the thickness of the AC in the distal femur in young students and determine its relationship with body mass index (BMI), muscle mass, body fat and sports practice.

MATERIALS AND METHODS

An observational cross-sectional study was conducted with healthy volunteers, between 15 and 25 years old. Anthropometric data were collected and the thickness of the femoral cartilage of the knee was measured at 5 points. In addition, the percentage of muscle and body fat was measured in a subgroup.

RESULTS

100 subjects were included in the study. The average age was 20 years (± 2.5). The average BMI was 23 kg/m² (± 3.1). AC was thicker in men and sportsmen, versus women and sedentary people, with a statistically significant difference. When comparing BMI with AC thickness no significant relationship was found; however, only 2 participants had BMI > 30.

CONCLUSIONS

Cartilage thickness has a direct relationship with the percentage of muscle, and inversely with the percentage of fat. BMI is not a good parameter when evaluating the dynamic behaviour of cartilage in non-obese youths.

Sonography: a sensitive and specific method for detecting trochlear cartilage pathologies

PURPOSE

MRI is now the modality of choice for evaluating articular cartilage. Nevertheless, it has some general drawbacks. Some patients cannot undergo MRI, and in others US scan could be the first examination and cartilage should be evaluated. Ultrasound could be a useful method for detecting trochlear cartilage low-grade lesions. In this study, our goal was to evaluate the efficacy of ultrasonography in detecting these lesions.

METHODS

All patients referred to our hospital, from July 2018 to July 2019, who were arthroscopic candidates due to sport-related pathologies, underwent ultrasound scan 1 day prior to surgery. Ultrasound assessment was performed by an expert radiologist, with a 13-MHz probe, located transversely proximal to the patella in different degrees of knee flexion to assess trochlear lesion grade and thickness. Arthroscopic examination of all patients was performed by an experienced orthopedic knee surgeon (second author). Sensitivity and specificity of ultrasound were calculated.

RESULTS

A total of 48 patients were involved in the study with a mean age of 33.2 years (SD: 9.7), between 19 and 51 years of age. Patients were 81% male (39 patients). The sensitivity of ultrasound in grading of trochlear cartilage lesion was 100%, meanwhile its specificity was 88.2% (30 cases had normal cartilage while this figure was 34 in arthroscopy).

CONCLUSION

Sonography is a low-cost, accessible diagnostic tool with high sensitivity and specificity for early detection of trochlear cartilage pathologies. It can play an important role as an outpatient diagnostic workup in patients with anterior knee pain.

Keratoconus: a potential risk factor for osteoarthritis

PURPOSE

This study was undertaken to compare the distal femoral cartilage thickness in patients with keratoconus (KC) with that of age- and sex-matched healthy controls, in order to identify a potential risk factor for early osteoarthritis in patients with KC and to allow initiation of early rehabilitation.

METHODS

Thirty-six KC patients between 18 and 35 years of age and 36 healthy controls were included in this study. Keratometry readings (K1, K2), central corneal thickness (CCT), anterior chamber depth (ACD), iridocorneal angle (ICA), and corneal volumes (CV) were measured using a Sirius imaging system (Costruzioni Strumenti Oftalmici, Italy). Also, the distal femoral cartilage thickness (DFCT) was assessed bilaterally using ultrasound by the same physiatrist. Lateral femoral condyle (LFC), intercondylar area (ICA), medial femoral condyle (MFC), and body mass index (BMI) values were recorded.

RESULTS

Patient and control groups were comparable in terms of age, gender, and BMI. On the other hand, patients with KC had a significant reduction in right LFC, MFC thickness and left ICA, MFC as compared to controls (p < 0.05). In the corneal topographic evaluation of the groups, it was observed that K₁, K₂, CCT, and ACD values differed significantly.

CONCLUSIONS

Detection of thinner DFCT in KC patients suggests that these patients may be future candidates of osteoarthritis.

Differential Diagnosis of Inflammatory Arthropathies by Musculoskeletal Ultrasonography: A Systematic Literature Review

Background: Differential diagnosis in early arthritis is challenging, especially early after symptom onset. Several studies applied musculoskeletal ultrasound in this setting, however, its role in helping diagnosis has yet to be clearly defined. The purpose of this work is to systematically assess the diagnostic applications of ultrasonography in early arthritis in order to summarize the available evidence and highlight possible gaps in knowledge. Methods: In December 2017, existing systematic literature reviews (SLR) on rheumatoid arthritis (RA), osteoarthritis (OA), psoriatic arthritis (PsA), polymyalgia rheumatica (PMR), calcium pyrophosphate deposition disease (CPPD), and gout were retrieved. Studies on ultrasound to diagnose the target conditions and detecting elementary lesions (such as synovitis, tenosynovitis, enthesitis, bone erosions, osteophytes) were extracted from the SLRs. The searches of the previous reviews were updated and data from new studies fulfilling the inclusion criteria extracted. Groups of reviewers worked separately for each disease, when possible diagnostic accuracy (sensitivities, specificities) was calculated from primary studies. When available, the reliability of ultrasound to detect elementary lesions was extracted. Results: For all the examined disease, recent SLRs were available. The new searches identified 27 eligible articles, with 87 articles included from the previous SLRs. The diagnostic performance of ultrasound in identifying diseases was addressed by 75 studies; in most of them, a single elementary lesion was used to define diagnosis, except for PMR. Only studies on RA included consecutive patients with new onset of arthritis, while studies on gout and CPPD often focused on subjects with mono-arthritis. Most of the remaining studies enrolled patients with a defined diagnosis. Synovitis was the most frequently detected lesion; clinical diagnosis was the most common reference standard. The diagnostic performance of ultrasound across different conditions was extremely variable. Ultrasound to identify elementary lesions was assessed in 38 studies in OA, gout and CPPD. Its performance in OA was very variable, with better results in CPPD and gout. The reliability of ultrasound was moderate to good for most lesions. Conclusions: Although a consistent amount of literature investigated the diagnostic application of ultrasound, in only a minority of cases its additional value over clinical diagnosis was tested. This SLR underlines the need for studies with a pragmatic design to identify the placement of ultrasound in the diagnostic pathway of new-onset arthritis.

The Transverse Infrapatellar View: A New Ultrasound Technique to Measure Distal Femoral Cartilage Thickness

OBJECTIVES

To examine the reliability and face validity of ultrasound (US) measurements of distal femoral cartilage thickness (CT) using the infrapatellar view (IPV) with knee extension compared to the traditional suprapatellar view (SPV) with knee hyperflexion in young asymptomatic participants and patients with painful knee osteoarthritis (KOA).

METHODS

The IPV was obtained in an extended knee position by placing the US transducer on the patellar tendon at a 60° angle tilted toward the distal femoral condyle in 19 young adults (control group) and 70 patients with KOA. The CT was measured at the medial femoral condyle, the intercondylar notch, and the lateral femoral condyle.

RESULTS

The inter-rater intraclass correlation coefficient was higher for IPV-based CT measurement (range, 0.856-0.858) compared to SPV-based CT measurement (range, 0.315-0.523) among the patients with symptomatic KOA. The IPV-based CT differed significantly between the control group and the KOA group at the intercondylar notch (P < .001) and lateral femoral condyle (P = .006). The SPV-based CT differed significantly between the control group and the KOA group only at the lateral femoral condyle region (P = .014).

CONCLUSIONS

An infrapatellar US evaluation of the distal femoral CT can be a reliable alternative method to a suprapatellar US evaluation for patients with KOA.

Prevalence and distribution of cartilage damage at the metacarpal head level in rheumatoid arthritis and osteoarthritis: an ultrasound study

OBJECTIVES

To determine the prevalence and distribution of US-detected qualitative cartilage damage at metacarpal heads of patients with RA and hand OA.

METHODS

Fifty-two RA patients and 34 patients with hand OA were enrolled. US examination of the metacarpal head cartilage from the II to V finger of both hands was performed. A total of 414 MCP joints in RA and 266 MCP joints in OA patients were scanned with a linear probe up to 22 MHz. Qualitative assessments using a previously described scoring system for cartilage damage were performed. The prevalence and distribution of cartilage damage were analysed. Multivariate regression analysis was used to determine the predictive value of age, gender, BMI, disease duration and the presence of RF and anti-CCP antibodies for US-detected cartilage damage.

RESULTS

The metacarpal head cartilage was positive for cartilage damage in 35.7% (148/414) of MCP joints in RA and in 43.6% (116/266) of MCP joints in OA patients. In RA, the hyaline cartilage of the II and III metacarpal heads (bilaterally) was the most frequently affected. In OA, cartilage damage was more homogeneously distributed in all MCP joints. Multivariate regression analysis showed that age and disease duration, but not gender, BMI or autoantibody status, were independent predictors of US-detected cartilage damage in RA.

CONCLUSION

Cartilage damage was found in more than one-third of the MCP joints in both RA and OA patients, and in RA patients, the II and III MCP joints were the most damaged.

Comparing the Accuracy of Radiography and Sonography in Detection of Knee Osteoarthritis: A Diagnostic Study

BACKGROUND:

Knee osteoarthritis (OA) is the most common degenerative disorder occurring in older people. Radiography and sonography are convenient techniques to detect diverse pathological features of knee OA.

AIM:

The aim of the present study was to evaluate the diagnostic efficacy of radiography and sonography in the detection of diverse features of knee OA.

METHODS:

In a prospective cross-sectional diagnostic accuracy study, 50 consecutive patients with suspected knee OA (40 women and 10 men, mean age 41.2 ± 6.1 years), referred to the rheumatology clinic of the Shohada Hospital of Khorramabad. All obtained magnetic resonance imaging (MRI), radiographic and sonography images were evaluated by two radiologists and rheumatologist with sufficient expertise in degenerative knee disorders. MRI has been considered as a gold standard test in evaluating other tests. The sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV) and accuracy with 95% confidence intervals of radiography and sonography in the diagnosis of knee OA were calculated.

RESULTS:

Prevalence of the marginal osteophyte, geode and decreased joint thickness were significantly higher in patients with age > 40 years compared to ≤ 40 years (P < 0.05). The incidence of diverse features of knee OA was not significantly different in terms of the patient’s gender, except for decreased joint space. The specificity of radiography was higher than its sensitivity.

CONCLUSION:

Our study showed that both radiography and sonography are useful imaging modalities, especially to diagnosis the positive cases of knee OA. The specificity of radiography is higher than to its sensitivity for all pathological features of knee OA. The sensitivity of sonography to detect some features of knee OA such as decreased joint thickness is considerably higher than radiography.

Standardized, musculoskeletal ultrasonographic reference values for healthy Korean adults

BACKGROUND/AIMS

To define standard reference values for musculoskeletal ultrasonography (MSUS) in Korea.

METHODS

A total of 251 healthy adults were recruited for this study. Ultrasonography was performed by experienced rheumatologists who had undergone four appropriate training programs in Korea. A General Electric LOGIQ electronic ultrasound device fitted with a 12 MHz linear transducer was employed. Mean values ± standard deviations (SDs) were defined as standard reference values. Intraclass correlation coefficients was employed to evaluate the extent of inter- and intraobserver agreement when MSUS measurements were made.

RESULTS

The 251 study participants included 122 males. Mean subject age was 28.6 years. The average bone-to-capsule distance of the right-side second and third metacarpophalangeal (MCP) joints were 0.68 and 0.72 mm respectively, and those of the left-side joints 0.62 and 0.68 mm. The cartilage thicknesses of the rightside second and third MCP joints were 0.55 and 0.55 mm, and those of the leftside joints were 0.55 and 0.56 mm, respectively. The bone-to-capsule distances of the right and left wrists were 0.80 and 0.82 mm. In 12.4% of participants (31/251), the erosion score of the humeral head was 1.71. In the right-side knee joint, mean cartilage thicknesses of the medial and lateral condyles were 1.86 and 2.03 mm in longitudinal scans. High overall interobserver agreement was evident after appropriate training that included instruction on standard MSUS methodology.

CONCLUSION

We defined standard reference values for MSUS in healthy Korean adults. The reliabilities of interobserver agreements were high after appropriate training program.

The Reliability of Suprapatellar Transverse Sonographic Assessment of Femoral Trochlear Cartilage Thickness in Healthy Adults

OBJECTIVES

To determine the intrasession reliability of femoral cartilage thickness measurements using sonography and extend the pool of normative data for cartilage thickness measurements assessed by sonography.

METHODS

A total of 77 healthy participants (55 men, 22 women), with an average age of 43 ± 18 (mean ± standard deviation) years, volunteered. Resting suprapatellar sonography was used to image trochlear cartilage thickness on 2 separate occasions a maximum of 7 days apart. Reliability was evaluated with intraclass correlation coefficients, Bland-Altman analysis, standard error of measurement, and the smallest real difference. Normative data was assessed using linear, multiple regression models and independent group t tests.

RESULTS

The test-retest level of agreement at all locations was high (intraclass correlation coefficient, 0.779-0.843), which increased to high-very high in young adults (intraclass correlation coefficient, 0.884-0.920). The standard error of measurement was 8.2% to 8.3% at all locations and reduced further to 5.4% to 6.3% in younger adults. The smallest real difference was between 22.8% and 23.1% for the full sample and 14.9% and 17.5% in young adults only. Multiple regression analyses demonstrated that age, weight, female sex, and a high physical activity frequency could significantly predict cartilage thickness at all locations (P < .05); however, female sex was the only significant independent predictor in all models (all P < .01). Females also had thinner cartilage at all locations (P < .01).

CONCLUSION

Suprapatellar sonography demonstrates high intratester reliability and measurement precision and is a promising method to assess trochlear cartilage thickness. Being female may impact femoral cartilage thickness more than other potential risk factors for knee osteoarthritis such as age, weight, and high physical activity frequency.

Ultrasonic cartilage thickness measurement is accurate, reproducible, and reliable-validation study using contrast-enhanced micro-CT

Background

Ultrasonography is a fast and patient-friendly modality to assess cartilage thickness. However, inconsistent results regarding accuracy have been reported. Therefore, we asked what are (1) the accuracy, (2) reproducibility, and (3) reliability of ultrasonographic cartilage thickness measurement using contrast-enhanced micro-CT for validation?

Methods

A series of 50 cartilage–bone plugs were harvested from fresh bovine and porcine joints. Ultrasonic cartilage thickness was determined using an A-mode, 20-MHz hand-held ultrasonic probe with native (1580 m/s) and adjusted speed of sound (1696 m/s). All measurements were performed by two observers at two different occasions. Angle of insonation was controlled by tilting the device and recording minimal thickness. Retrieval of exact location for measurement was facilitated by aligning the circular design of both cartilage–bone plug and ultrasonic device. There was no soft tissue interference between cartilage surface and ultrasonic probe. Ground truth measurement was performed using micro-CT with iodine contrast agent and a voxel size of 16 μm. The mean cartilage thickness was 1.383 ± 0.402 mm (range, 0.588–2.460 mm).

Results

Mean accuracy was 0.074 ± 0.061 mm (0.002–0.256 mm) for native and 0.093 ± 0.098 mm (0.000–0.401 mm) for adjusted speed of sound. Bland–Altman analysis showed no systematic error. High correlation was found for native and adjusted speed of sound with contrast-enhanced micro-CT (both r = 0.973; p < 0.001). A perfect agreement for reproducibility (intraclass correlation coefficient [ICC] 0.992 and 0.994) and reliability (ICC 0.993, 95% confidence interval 0.990–0.995) was found.

Conclusions

Ultrasonic cartilage thickness measurement could be shown to be highly accurate, reliable, and reproducible. The A-mode ultrasonic cartilage thickness measurement is a fast and patient-friendly modality which can detect early joint degeneration and facilitate decision making in joint preserving surgery.

Electronic supplementary material

The online version of this article (10.1186/s13018-019-1099-8) contains supplementary material, which is available to authorized users.

Ultrasonographic measurements of the metacarpophalangeal and talar cartilage thicknesses: A reliability study in healthy subjects

BACKGROUND

Assessment of the joint cartilage using ultrasound imaging is important.

OBJECTIVE

Our aim was to investigate the reliabilities of ultrasonographic measurements for talus dome (TCT) and metacarpal cartilage thicknesses (MCT).

METHODS

Twenty healthy volunteers were recruited in the study. Every day, five physiatrists measured eight joint cartilage thicknesses. They repeated all the measurements in five consecutive days.

RESULTS

Intra-observer intraclass correlation coefficient (ICC) values were "excellent" for all MCTs, except for the 3rd left MCT on the 1st day, 4th left MCT on the 1st day and 4th right MCT on the 3rd day which were "good". They were "excellent" for the TCT measurements, except for the left side on the 3rd day and the right side on the 4th day which were "good". Inter-observer ICC values pertaining to the 2nd MCT measurements were "excellent" for all sonographers. Third and 4th MCT measurements (at least one side) were "excellent" for four and three sonographers, respectively. On the other hand, while TCT measurements were "excellent" for 4 sonographers.

CONCLUSIONS

Our results have shown that sonographic measurements of MCT and TCT have good to excellent reliabilities in healthy adults. These findings support the use of ultrasound for cartilage assessment in various diseases.

A novel ultrasound scanning approach for evaluating femoral cartilage defects of the knee: comparison with routine magnetic resonance imaging

Background

This study aimed to assess a novel ultrasound (US) scanning approach in evaluating knee femoral cartilaginous defects, compared with magnetic resonance imaging (MRI, commonly used for knee imaging) and arthroscopy (gold standard).

Methods

Sixty-four consecutive patients (65 knees) were prospectively evaluated between April 2010 and July 2011.

Results

The overall sensitivity (62.2 and 69.4%), specificity (92.9 and 90.5%), accuracy (75.4 and 78.5%), and adjusted positive (88.7 and 90.4%) and negative predictive (69.5 and 73.3%) were similar for both radiologists (weighted κ = 0.76). Furthermore, agreement between grading by US and MRI was substantial (weighted κ = 0.61).

Conclusions

In conclusion, the novel US scanning approach allows similar diagnostic performance compared to routine MRI for knee cartilage defects. US is more accessible, easier to perform, and less expensive than MRI, with potential advantages of easier initial screening and assessment of cartilage defects.

Electronic supplementary material

The online version of this article (10.1186/s13018-018-0887-x) contains supplementary material, which is available to authorized users.

How precisely does ultrasonographic evaluation reflect the histological status of the articular cartilage of the knee joint?

The thickness and the grade of the articular cartilages of the knee of 34 patients who underwent total knee arthroplasty were evaluated by ultrasound (US) and by histology. The US grade correlated with the histological grade and the thickness of the articular cartilage measured by US. The thickness measured by US was significantly correlated with that measured by histology for the medial condyle. The US thickness was significantly less than the histological thickness for thicker articular cartilages. US grading and the thickness of the articular cartilages evaluated by US is sufficiently reliable to indicate their histological status.

Clinimetrics of ultrasound pathologies in osteoarthritis: systematic literature review and meta-analysis

OBJECTIVE

The aims of this study were to systematically review clinimetrics of commonly assessed ultrasound pathologies in knee, hip and hand osteoarthritis (OA), and to conduct a meta-analysis for each clinimetric.

METHODS

Medline, Embase, and Cochrane Library databases were searched from their inceptions to September 2016. According to the Outcome Measures in Rheumatology (OMERACT) Instrument Selection Algorithm, data extraction focused on ultrasound technical features and performance metrics. Methodological quality was assessed with modified 19-item Downs and Black score and 11-item Quality Appraisal of Diagnostic Reliability (QAREL) score. Separate meta-analyses were performed for clinimetrics: (1) inter-rater/intra-rater reliability; (2) construct validity; (3) criteria validity; and (4) internal/external responsiveness. Statistical Package for the Social Sciences (SPSS), Excel and Comprehensive Meta-analysis were used.

RESULT

Our search identified 1126 records; of these, 100 were eligible, including a total of 8542 patients and 32,373 joints. The average Downs and Black score was 13.01, and average QAREL was 5.93. The stratified meta-analysis was performed only for knee OA, which demonstrated moderate to substantial reliability [minimum kappa > 0.44(0.15,0.74), minimum intraclass correlation coefficient (ICC) > 0.82(0.73-0.89)], weak construct validity against pain (r = 0.12 to 0.27), function (r = 0.15 to 0.23), and blood biomarkers (r = 0.01 to 0.21), but weak to strong correlation with plain radiography (r = 0.13 to 0.60), strong association with Magnetic Resonance Imaging (MRI) [minimum r = 0.60(0.52,0.67)] and strong discrimination against symptomatic patients (OR = 3.08 to 7.46). There was strong criterion validity against cartilage histology [r = 0.66(-0.05,0.93)], and small to moderate internal [standardized mean difference(SMD) = 0.20 to 0.58] and external (r = 0.35 to 0.43) responsiveness to interventions.

CONCLUSION

Ultrasound demonstrated strong criterion validity with cartilage histology, poor to strong correlation with patient findings and MRI, moderate reliability, and low responsiveness to interventions.

PROSPERO REGISTRATION NO

CRD42016039954.

Sagittal-Plane Knee Moment During Gait and Knee Cartilage Thickness

CONTEXT

  Understanding the factors associated with thicker cartilage in a healthy population is important when developing strategies aimed at minimizing the cartilage thinning associated with knee osteoarthritis progression. Thicker articular cartilage is commonly thought to be healthier cartilage, but whether the sagittal-plane biomechanics important to gait are related to cartilage thickness is unknown.

OBJECTIVE

  To determine the relationship of a weight-bearing region of the medial femoral condyle's cartilage thickness to sagittal gait biomechanics in healthy individuals.

DESIGN

  Descriptive laboratory study.

SETTING

  Laboratory.

PATIENTS OR OTHER PARTICIPANTS

  Twenty-eight healthy participants (15 women: age = 21.1 ± 2.1 years, height = 1.63 ± 0.07 m, weight = 64.6 ± 9.9 kg; 13 men: age = 22.1 ± 2.9 years, height = 1.79 ± 0.05 m, weight = 75.2 ± 9.6 kg).

MAIN OUTCOME MEASURE(S)

  Tibiofemoral angle (°) was obtained via goniometric assessment, thickness of the medial femoral condyle cartilage (mm) was obtained via ultrasound imaging, and peak internal knee-extensor moment (% body weight · height) was measured during 10 trials of over-ground walking at a self-selected pace. We used linear regression to examine the extent to which peak internal knee-extensor moment predicted cartilage thickness after accounting for tibiofemoral angle and sex.

RESULTS

  Sex and tibiofemoral angle (12.3° ± 3.2°) were entered in the initial step as control factors (R² = 0.01, P = .872). In the final step, internal knee-extensor moment (1.5% ± 1.3% body weight · height) was entered, which resulted in greater knee-extensor moment being related to greater cartilage thickness (2.0 ± 0.3 mm; R²Δ = 0.31, PΔ = .003).

CONCLUSION

  Individuals who walked with a greater peak internal knee-extensor moment during gait had a cartilage structure that is generally considered beneficial in a healthy population. Our study offers promising findings that a potentially modifiable biomechanical factor is associated with cartilage status in a healthy population. Establishing these baseline relationships in uninjured populations may help us to better understand potential factors related to maladaptive gait patterns that predispose a person to adverse changes in the cartilage environment.

Relationship Between Q-Angle and Articular Cartilage in Female Patients With Symptomatic Knee Osteoarthritis: Ultrasonographic and Radiologic Evaluation

OBJECTIVES

This study aims to examine the association between Q-angle and clinical, radiological, and ultrasonographic findings in patients with knee osteoarthritis (OA).

PATIENTS AND METHODS

Sixty-eight female patients (mean age 59.8±6.8 years; range 39 to 78 years) diagnosed with knee OA were included in this study and classified into two groups according to Q-angle of symptomatic knees: low Q-angle group (LQ) (n=40) and high Q-angle group (HQ) (n=28) (LQ-angle <15° and HQ-angle ≥15°, respectively). Patients were clinically assessed for pain and functional status by using a visual analog scale and the Western Ontario and McMaster Universities Arthritis Index. X-rays of knees were scored using the Kellgren-Lawrence OA grading system. Symptomatic knees were also evaluated using ultrasonography for distal femoral cartilage thickness/grading.

RESULTS

No significant difference was observed in clinical and imaging findings between the groups (p>0.05). HQ-angle measurements were positively correlated with cartilage grading by ultrasonography (r=0.435, p=0.033) and Kellgren-Lawrence grading system (r=0.435, p=0.021), and negatively correlated with cartilage thickness measurements of the medial femoral condyle (r=-0.399, p=0.036).

CONCLUSION

We found that HQ-angle was associated with cartilage thickness measurements of the medial femoral condyle and cartilage grading by ultrasonography and the Kellgren-Lawrence grading system in patients with knee OA.

Ultrasonographic Assessment of Femoral Cartilage Thickness in Patients With Cerebral Palsy

BACKGROUND

Cerebral palsy (CP) is one of the most disabling syndromes in children. To our knowledge, there has not yet been any reported evaluation by ultrasonography of the effect of CP on distal femoral cartilage. The value of understanding this effect on cartilage is that sonographic evaluation of cartilage thickness may help physicians to predict the joint health of these children.

OBJECTIVE

To determine whether femoral cartilage thickness in patients with CP is different from that in healthy control subjects.

DESIGN

Cross-sectional study.

SETTING

National tertiary rehabilitation center.

PATIENTS

The study included 40 patients with diplegic CP (23 male and 17 female) and 51 healthy control subjects (29 male and 22 female).

METHODS

Demographic and clinical characteristics were recorded. Cartilage thicknesses were measured.

MAIN OUTCOME MEASURE

Cartilage thickness measurements were taken from the medial and lateral condyles, and intercondylar areas of both knees.

RESULTS

Both groups were similar in terms of age, gender, and weight (P > .05). The mean cartilage thickness measurements of the medial condyle and intercondylar area of knees in the CP group were significantly less than those in the healthy control group (all P < .05). There was moderate negative correlation between age and all femoral cartilage thickness measurements in the CP group. There was no correlation between age and femoral cartilage thickness measurements in the healthy group. There was a negative correlation between Gross Motor Functional Classification System levels and cartilage thickness in the CP group. The highest cartilage thickness measurements were detected in level 1 patients, and the lowest measurements were detected in level 5 patients.

CONCLUSION

This study showed that patients with CP have a thinner femoral cartilage than healthy control subjects. Management of patients with CP should include close surveillance.

LEVEL OF EVIDENCE

III.

Evaluation of knee cartilage thickness: A comparison between ultrasound and magnetic resonance imaging methods

BACKGROUND

Establishing clinically accessible measures of cartilage health is critical for assessing effectiveness of protocols to reduce risk of osteoarthritis (OA) development and progression. Cartilage thickness is one important measure in describing both OA development and progression. The objective was to determine the relationship between ultrasound and MRI measures of cartilage thickness in the medial femoral condyle.

METHODS

Mean cartilage thicknesses of the left medial femoral cartilage were measured via T1 weighted MRI and ultrasound imaging from transverse, anterior, middle, and posterior medial femoral regions in 10 healthy females (Mean±Std Dev) (1.66±0.08m, 59.5±8.3kg, 21.6±1.4years) and nine healthy males (1.80±0.08m, 79.1±6.2kg, 21.7±1.5years). Pearson correlations examined relationships between MRI and ultrasound measures. Bland-Altman plots evaluated agreement between the imaging modalities.

RESULTS

Transverse ultrasound thickness measures were significantly positively correlated with MRI middle (r=.67, P≤.05) and posterior thicknesses (r=.49, P≤.05) while the middle and posterior longitudinal ultrasound measures were significantly correlated to their respective MRI regions (r=.67, P≤.05 & r=.59 P≤.05, respectively). There was poor absolute agreement between correlated measures with ultrasound thickness measures being between 1.9 and 2.8mm smaller than MRI measures.

CONCLUSIONS

These results suggest that ultrasound may be a viable clinical tool to assess relative cartilage thickness in the middle and posterior medial femoral regions. However, the absolute validity of the ultrasound measure is called into question due to the larger MRI-based thickness measures.

LEVEL OF EVIDENCE

Level IV.

Efficacy of pulsed Nd:YAG laser in the treatment of patients with knee osteoarthritis: a randomized controlled trial

The purpose of this study was to investigate the effects of pulsed Nd:YAG laser plus glucosamine/chondroitin sulfate (GCS) in patients with knee osteoarthritis (KOA) by examining changes in pain and knee function, as well as synovial thickness (ST) and femoral cartilage thickness (FCT). Sixty-seven male patients participated, with a mean (SD) age of 53.85 (4.39) years, weight of 84.01 (4.70) kg, height of 171.51 (3.96) cm, and BMI of 28.56 (1.22). Group 1 was treated with high-intensity laser therapy (HILT), GCS, and exercises (HILT + GCS + EX). Group 2 was treated with GCS plus exercises (GCS + EX), and group 3 received placebo laser plus exercises (PL + EX). The outcomes measured were pain level and functional disability using the visual analog scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), respectively. ST and FCT were measured by ultrasound examination. Statistical analyses were performed to compare differences between baseline and after 6 weeks of treatment and then after 3 months of follow-up. Statistical significance was set at p < 0.05. VAS and WOMAC were significantly decreased in all groups after 6 weeks, with nonsignificant differences between 6 weeks and 3 months of follow-up. ST was significantly decreased in the HILT + GCS + EX group posttreatment, with nonsignificant decreases in the GCS + EX and PL + EX groups, as well as nonsignificant differences to FCT in all groups. Overall, pulsed Nd:YAG laser combined with GCS and exercises was more effective than GCS + EX and exercises alone in the treatment of KOA patients.

Ultrasonographic evaluation of femoral cartilage thickness in patients with psoriatic arthritis

BACKGROUND

Psoriatic arthritis (PsA) is a common form of arthritis that may vary from asymmetric oligoarthritis to symmetric polyarthritis and spondyloarthritis.

OBJECTIVES

To evaluate femoral cartilage thickness using ultrasonography in patients with PsA.

METHODS

Thirty-three patients (24 female, 9 male) with a diagnosis of PsA and 31 age-, sex- and body mass index-similar healthy subjects were enrolled in this study. Demographic and clinical characteristics of the patients were recorded, including disease duration, morning stiffness and medications. The femoral cartilage thicknesses of both knees (while held in maximum flexion) were measured with a 7-12 MHz linear probe. Three mid-point measurements were taken from both knees (at the lateral condyle, intercondylar area and medial condyle).

RESULTS

Cartilage thicknesses were similar between PsA patients and healthy control subjects. However, there were significant correlations between cartilage thickness and the Maastricht Ankylosing Spondylitis Enthesitis Score, Bath AS functional index and Bath AS disease activity index scores.

CONCLUSION

Femoral cartilage thickness is similar between PsA patients and healthy controls. The femoral cartilage thickness in PsA patients is associated with disease activity, functional inadequacy, and enthesopathy scores.

Relationship between atherosclerosis and knee osteoarthritis as graded by radiography and ultrasonography in females

[Purpose] The aim of this study was to assess the relationship between atherosclerosis and knee osteoarthritis grade in women as assessed by both ultrasonography and radiography. [Subjects and Methods] Seventy women diagnosed with knee osteoarthritis were classified into two groups according to cartilage grading/radiographic grading. Patients with Kellgren-Lawrence grades 1 and 2 were included in group 1, while those with Kellgren-Lawrence grades 3 and 4 were included in group 2. Patients with cartilage grades 1-3 were included in group 1, while those with cartilage grades 4-6 were included in group 2. Patients were clinically assessed using a visual analog scale and the Western Ontario and McMaster Universities Arthritis Index. Radiographic osteoarthritis grade was scored using the Kellgren and Lawrence grading system. Using ultrasonography, symptomatic knees were graded and evaluated for distal femoral cartilage thickness. Carotid intima-media thickness and serum lipid levels were measured to assess atherosclerosis. [Results] Carotid intima-media thickness measurements were higher in group 2 than in group 1 as determined by the Kellgren-Lawrence and cartilage grading systems. Carotid intima-media thickness measurements were positively correlated with both the ultrasonographic cartilage grade and Kellgren-Lawrence. [Conclusion] The results of this study suggest that osteoarthritis as assessed by ultrasonography was successful and comparable to assessment with radiography. We showed a correlation between atherosclerosis and ultrasonographic knee osteoarthritis grade.

Ultrasonographic evaluation of the femoral cartilage thickness in patients with hypothyroidism

[Purpose] The aim of this study was to investigate the effects of hypothyroidism on femoral cartilage thickness by using ultrasound, which has been found to be useful in the early diagnosis of knee osteoarthritis. [Subjects and Methods] Forty patients diagnosed with hypothyroidism and 30 age-, gender-, smoking status, physical activity-, and body mass index-matched healthy subjects were enrolled. The thickness of the femoral articular cartilage was measured using a 7- to 12-MHz linear probe. Three mid-point measurements were taken from each knee at the lateral condyle, intercondylar area, and medial condyle. [Results] Age, gender, body mass index, smoking status, and physical activity were similar between the groups, but patients with hypothyroidism had thinner femoral cartilage than the healthy controls at all measurement sites. Nonetheless, the differences were not statistically significant (except in the case of the left medial condyle). [Conclusion] Ultrasonographic measurement of femoral cartilage thickness may be useful in the early diagnosis of knee osteoarthritis in patients with hypothyroidism.

Ultrasonographic Assessment of the Distal Femoral Cartilage Thickness in Patients with Homozygous Sickle Cell Disease

OBJECTIVE

To compare the distal femoral cartilage thickness of patients with sickle cell disease (SCD) with those of healthy subjects using ultrasonography.

METHODS

The study comprised 30 patients with SCD (16 male, 14 female; mean age, 30.1 years) and 30 age- and sex-matched healthy subjects. Demographic features and medications of the patients were recorded. With the knees held in maximum flexion, the femoral cartilage thickness was measured bilaterally with a 7- to 12-MHz linear probe. Using ultrasonography, 3 midpoint measurements were taken from both knees: lateral femoral condyle (LFC), intercondylar area (ICA), and medial femoral condyle (MFC).

RESULTS

Patients with SCD had thinner femoral cartilage thickness values at LFC (P = 0.004), at MFC (P = 0.000), and ICA (P = 0.002) when compared with those of the healthy subjects. Patients with SCD also had lower Hb levels (P = 0.000) levels. Weak positive correlations were determined between Hemoglobin (Hb) levels and ultrasonographic measurements in the SCD group at MFC (r = 0.331, P = 0.010), and ICA (r = 0.289 , P = 0.025 ). Low levels of Hb seem to affect the femoral cartilage thickness.

CONCLUSION

These preliminary findings of decreased femoral cartilage thickness in SCD patients should be complemented with future studies. The possibility of early knee joint degeneration and eventual osteoarthritis in SCD should be kept in mind.

Comparison of Diagnostic Performance of Semi-Quantitative Knee Ultrasound and Knee Radiography with MRI: Oulu Knee Osteoarthritis Study

Osteoarthritis (OA) is a common degenerative musculoskeletal disease highly prevalent in aging societies worldwide. Traditionally, knee OA is diagnosed using conventional radiography. However, structural changes of articular cartilage or menisci cannot be directly evaluated using this method. On the other hand, ultrasound is a promising tool able to provide direct information on soft tissue degeneration. The aim of our study was to systematically determine the site-specific diagnostic performance of semi-quantitative ultrasound grading of knee femoral articular cartilage, osteophytes and meniscal extrusion, and of radiographic assessment of joint space narrowing and osteophytes, using MRI as a reference standard. Eighty asymptomatic and 79 symptomatic subjects with mean age of 57.7 years were included in the study. Ultrasound performed best in the assessment of femoral medial and lateral osteophytes, and medial meniscal extrusion. In comparison to radiography, ultrasound performed better or at least equally well in identification of tibio-femoral osteophytes, medial meniscal extrusion and medial femoral cartilage morphological degeneration. Ultrasound provides relevant additional diagnostic information on tissue-specific morphological changes not depicted by conventional radiography. Consequently, the use of ultrasound as a complementary imaging tool along with radiography may enable more accurate and cost-effective diagnostics of knee osteoarthritis at the primary healthcare level.

Surface roughness and thickness analysis of contrast-enhanced articular cartilage using mesh parameterization

OBJECTIVE

Articular cartilage (AC) morphology is an important metric for characterizing degeneration. We propose a novel morphologic analysis using mesh parameterization, enabling the use of surface roughness and thickness metrics to characterize degeneration in a rodent model of post-traumatic osteoarthritis.

METHODS

Six rats underwent anterior cruciate ligament transection (ACL-T) and six were controls (Control). At 4-weeks, femora and tibiae were harvested and imaged using contrast-enhanced micro-computed tomography (μCT). Cartilage surfaces were manually outlined, and 2-dimensional thickness maps were generated using mesh parameterization and analyzed by thickness and surface roughness (Sa). The parameterization technique was validated against the direct distance transform (DDT) and histologic AC thickness from sagittal Safranin-O/Fast-Green sections. Parameterization and DDT measurements were also validated using known, virtual shapes with zero, one, and two planes of curvature.

RESULTS

Parameterization had 0.00-6.26% error and DDT had 5.06-12.02% error in determining thicknesses of known shapes. Parameterization thickness correlated highly to DDT thickness (femur: r = 0.978, P < 0.001; tibia: r = 0.992, P < 0.001) and histologic thickness (femur: r = 0.952, P < 0.001; tibia: r = 0.959, P < 0.001). Thickness maps enabled visualization and quantification of AC degeneration. ACL-T samples displayed general thickening of cartilage, with adjacent regions of thickening and thinning on the medial femoral condyle. Compared to Control, ACL-T thickness was higher in the whole femur, whole tibia, and all compartments and sub-compartments. Sa was higher in the whole femur and medial and lateral condyle, and the whole tibia and medial and lateral plateau. The largest increases in Sa were observed on the medial femoral condyle.

CONCLUSIONS

Cartilage analysis using parameterization effectively characterized early degeneration in AC, including sub-compartmental thickening/thinning, and is a powerful tool for assessing degeneration in preclinical osteoarthritis.

The dynamic evolution of rheumatology in Korea

Rheumatology was first recognized as a distinct clinical specialty in Korea just 35 years ago. Young professors who were trained in rheumatology in the USA and afterwards returned to Korea contributed substantially to advances in rheumatology clinical practice, educational programmes and research activities. They also established the Korean Rheumatism Association, later renamed the Korean College of Rheumatology. These young rheumatologists had a major role not only in raising the level of clinical and scientific activities, but also in promoting academic exchanges around the Asia-Pacific region, the USA and Europe. Subsequently, Korea's rapid economic growth and high education level enabled rheumatology to advance rapidly. Today, continued efforts are required to raise the standard of clinical and basic research, to optimize clinical practice with regard to new biologic agents, to exploit personalized and targeted therapies for the rheumatic diseases, and to meet the medical demands of Korea's ageing society.

Comparison of Intact Knee Cartilage Thickness in Patients with Traumatic Lower Extremity Amputation and Nonimpaired Individuals

OBJECTIVE

The aim of this study was to assess the femoral articular cartilage thickness of the intact knee in patients with traumatic lower extremity amputation compared with nonimpaired individuals.

DESIGN

A total of 30 male patients with traumatic lower extremity amputation (mean [SD] age, 31.2 [6.3] yrs) and a random sample of 53 age-matched and body mass index-matched male nonimpaired individuals (mean [SD] age, 29.8 [6.3] yrs) participated in the study. Exclusion criteria were age younger than 18 yrs, history of significant knee injury, previous knee surgery, or rheumatic disease. The femoral articular cartilage thickness was measured using ultrasound at the midpoints of the medial condyle, the intercondylar notch, and the lateral condyle. Ultrasonographic cartilage measurement was performed on the intact side of the patients with amputation and on both sides of the nonimpaired individuals.

RESULTS

The femoral articular cartilage thickness of the intact knees of the patients with amputation was significantly decreased at the lateral and medial condyles compared with the nonimpaired individuals (P < 0.05). There was no significant difference in the measurements at the intercondylar notch between the patients with amputation and the nonimpaired individuals (P > 0.05).

CONCLUSIONS

There was a premature cartilage loss in the intact limb knee of the patients with traumatic amputation. This result supports the view that patients with traumatic lower extremity amputation are at increased risk for developing knee osteoarthritis in the intact limb.

Ultrasonographic measurement of the femoral cartilage thickness in patients with occupational lead exposure

The objective of the present study is to compare distal femoral cartilage thicknesses of patients with occupational lead exposure with those of healthy subjects by using ultrasonography. A total of 48 male workers (a mean age of 34.8±6.8 years and mean body mass index (BMI) of 25.8±3.1 kg/m(2)) with a likely history of occupational lead exposure and age- and BMI-matched healthy male subjects were enrolled. Demographic and clinical characteristics of the patients, that is, age, weight, height, occupation, estimated duration of lead exposure, and smoking habits were recorded. Femoral cartilage thickness was assessed from the midpoints of right medial condyle (RMC), right lateral condyle (RLC), right intercondylar area (RIA), left medial condyle (LMC), left lateral condyle (LLC), and left intercondylar area (LIA) by using ultrasonography. Although the workers had higher femoral cartilage thickness values at all measurement sites when compared with those of the control subjects, the difference reached statistical significance at RLC (P=0.010), LMC (P=0.001), and LIA (P=0.039). There were no correlations between clinical parameters and cartilage-thickness values of the workers. Subjects with a history of lead exposure had higher femoral cartilage thickness as compared with the healthy subjects. Further studies, including histological evaluations, are awaited to clarify the clinical relevance of this increase in cartilage thickness and to explore the long-term follow-up especially with respect to osteoarthritis development.

Ultrasound of knee osteoarthritis: interobserver agreement and correlation with Western Ontario and McMaster Universities Osteoarthritis

The aim of this work was to assess the reproducibility of ultrasound findings of knee osteoarthritis and to correlate ultrasound findings with Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Prospective study was conducted upon 80 patients (56 F, 24 M; mean age 57 years) with primary osteoarthritis of knee joint. All patients underwent clinical assessment with calculation of WOMAC and high-resolution ultrasound of the knee joint. The ultrasound images were analyzed for cartilage thinning, osteophytes, synovial effusion, synovial proliferation, popliteal cyst, and meniscal protrusion. Image analysis was performed by two readers and linear regression analysis was used to determine association of ultrasound findings with WOMAC. There was excellent inter-observer agreement of both readers for cartilage thinning (k = 0.99, P = 0.001), osteophytes (k = 0.94, P = 0.001), synovial effusion (k = 0.98, P = 0.001), synovial thickening (k = 0.96, P = 0.001), popliteal cyst (k = 1.00, P = 0.001), and meniscal protrusion (k = 0.86, P = 0.001). There was significant association of WOMAC with cartilage changes (t = 3.406, 3.302, P = 0.001), osteophytes (t = 3.841, 3.006, P = 0.001), and synovial effusion (t = 4.140 and 2.787, P = 0.05) of both readers. We concluded that ultrasound is a reproducible method for assessment of knee osteoarthritis and well correlated with WOMAC.

Ultrasonographic Measurement of the Femoral Cartilage Thickness in Patients with Behçet's Disease

OBJECTIVE

To evaluate femoral cartilage thickness in patients with Behçet's disease (BD) by using ultrasonography.

METHODS

Thirty-one patients with BD (18 M, 13 F; mean age: 32.87 ± 8.5 years) and 31 age-, gender- and body mass index-matched healthy subjects were enrolled. Demographic features and medications of the patients were recorded. The femoral cartilage thicknesses of both knees were measured with a 7-12 MHz linear probe while subjects' knees were held in maximum flexion. Three mid-point measurements were taken from both knees: lateral femoral condyle (LFC), intercondylar area (ICA) and medial femoral condyle (MFC).

RESULTS

Cartilage measurements of BD patients were significantly thinner at the ICA (p = 0.009) and LFC (p = 0.007) on the left knee, and at the MFC on both sides (both p < 0.05). Left knee cartilage thickness value at MFC (p = 0.005) was decreased in BD patients with arthritis compared to the healthy control group.

CONCLUSION

These preliminary findings of decreased femoral cartilage thickness in BD patients with arthritis should be complemented with future studies. However, the possibility of early knee joint degeneration and eventual osteoarthritis in BD should also be kept in mind.

A superficial hyperechoic band in human articular cartilage on ultrasonography with histological correlation: preliminary observations

Purpose:

To demonstrate the superficial hyperechoic band (SHEB) in articular cartilage by using ultrasonography (US) and to assess its correlation with histological images.

Methods:

In total, 47 regions of interest (ROIs) were analyzed from six tibial osteochondral specimens (OCSs) that were obtained after total knee arthroplasty. Ultrasonograms were obtained for each OCS. Then, matching histological sections from all specimens were obtained for comparison with the ultrasonograms. Two types of histological staining were used: Safranin-O stain (SO) to identify glycosaminoglycans (GAG) and Masson’s trichrome stain (MT) to identify collagen. In step 1, two observers evaluated whether there was an SHEB in each ROI. In step 2, the two observers evaluated which histological staining method correlated better with the SHEB by using the ImageJ software.

Results:

In step 1 of the analysis, 20 out of 47 ROIs showed an SHEB (42.6%, kappa=0.579). Step 2 showed that the SHEB correlated significantly better with the topographical variation in stainability in SO staining, indicating the GAG distribution, than with MT staining, indicating the collagen distribution (P<0.05, kappa=0.722).

Conclusion:

The SHEB that is frequently seen in human articular cartilage on high-resolution US correlated better with variations in SO staining than with variations in MT staining. Thus, we suggest that a SHEB is predominantly related to changes in GAG. Identifying an SHEB by US is a promising method for assessing the thickness of articular cartilage or for monitoring early osteoarthritis.

Ultrasonographic evaluation of femoral cartilage thickness in patients with ankylosing spondylitis

OBJECTIVE

To evaluate femoral cartilage thickness in patients with ankylosing spondylitis (AS) by using ultrasonography.

METHODS

Eighty-four patients (55 M, 29 F) with a diagnosis of AS and 84 age-, gender- and body mass index-matched healthy subjects were enrolled. Demographic and clinical characteristics of the patients including disease duration, morning stiffness and medications were recorded. The femoral cartilage thicknesses of both knees were measured with a 7-12 MHz linear probe while subjects' knees were held in maximum flexion. Three mid-point measurements were taken from both knees (lateral femoral condyle (LFC), intercondylar area (ICA) and medial femoral condyle (MFC)).

RESULTS

Concerning both ICA (p < 0.001) and left MFC (p = 0.013), cartilage measurements were significantly thicker in AS patients than control subjects. In a subgroup analysis (anti-tumour necrosis factor (TNF) users vs anti-TNF naive), cartilage thickness measurements - bilateral ICA (p = 0.000) and left MFC (p = 0.017) - were found to be greater in AS patients under anti-TNF treatment (n = 65) when compared with those of healthy controls.

CONCLUSION

We imply that AS patients seem to have thicker femoral cartilage, which could be related to anti-TNF treatment.

Feasibility of ultrasound imaging of osteochondral defects in the ankle: a clinical pilot study

Talar osteochondral defects (OCDs) are imaged using magnetic resonance imaging (MRI) or computed tomography (CT). For extensive follow-up, ultrasound might be a fast, non-invasive alternative that images both bone and cartilage. In this study the potential of ultrasound, as compared with CT, in the imaging and grading of OCDs is explored. On the basis of prior CT scans, nine ankles of patients without OCDs and nine ankles of patients with anterocentral OCDs were selected and classified using the Loomer CT classification. A blinded expert skeletal radiologist imaged all ankles with ultrasound and recorded the presence of OCDs. Similarly to CT, ultrasound revealed typical morphologic OCD features, for example, cortex irregularities and loose fragments. Cartilage disruptions, Loomer grades IV (displaced fragment) and V (cyst with fibrous roof), were visible as well. This study encourages further research on the use of ultrasound as a follow-up imaging modality for OCDs located anteriorly or centrally on the talar dome.

An ultrasound score for knee osteoarthritis: a cross-sectional validation study

OBJECTIVE

To develop standardized musculoskeletal ultrasound (MUS) procedures and scoring for detecting knee osteoarthritis (OA) and test the MUS score's ability to discern various degrees of knee OA, in comparison with plain radiography and the 'Knee injury and Osteoarthritis Outcome Score' (KOOS) domains as comparators.

METHOD

A cross-sectional study of MUS examinations in 45 patients with knee OA. Validity, reliability, and reproducibility were evaluated.

RESULTS

MUS examination for knee OA consists of five separate domains assessing (1) predominantly morphological changes in the medial compartment, (2) predominantly inflammation in the medial compartment, (3) predominantly morphological changes in the lateral compartment, (4) predominantly inflammation in the lateral compartment, and (5) effusion. MUS scores displayed substantial reliability and reproducibility, with interclass correlations coefficients ranging from 0.75 to 0.97 for the five domains. Construct validity was confirmed with statistically significant correlation coefficients (0.47-0.81, P < 0.01).

CONCLUSION

The MUS score suggested in this study was reliable and valid in detecting knee OA. In comparison with standing radiographs of the knees, the score detected all aspects of knee OA with relevant precision.

Ultrasonographic assessment of the femoral cartilage in osteoarthritis patients with and without osteoporosis

BACKGROUND

The relationship between osteoporosis (OP) and osteoarthritis (OA) is yet unclear.

AIM

To evaluate the possible effect of OP on the femoral cartilage thickness in female patients with knee OA.

MATERIALS AND METHODS

Eighty patients with a diagnosis of knee OA were enrolled. Forty subjects who also had OP comprised Group I and the remaining 40 OA subjects comprised Group II. Antero-posterior knee radiographs were obtained in standing position and they were evaluated according to Kelgren-Lawrence (K-L) grading scale. Femoral cartilage evaluations were performed using a linear array US probe (7-12 MHz). In addition, ultrasonographic femoral cartilage grading was also performed for each knee.

RESULTS

Left knee scores pertaining to both gradings were found to be lower (p = 0.02, p = 0.04, respectively) in Group I when compared with those of Group II. The two grading scores were positively correlated for both knees-statistically significant only for the right side (r = 0.727, p = 0.01). No significant difference was found between the groups in terms of femoral cartilage thicknesses (all p > 0.05).

DISCUSSION

Ultrasonographic and roentgenographic gradings were consistent and patients with OP had lower scores for both gradings. On the other hand, the presence of OP did not seem to have any effect on cartilage thickness measurements.

CONCLUSIONS

To the best knowledge of the authors, this study is the first to have explored the impact of OP on OA using US in the literature.