Cartilage Thickness Measurements Research Articles

Test-retest reliability and smallest detectable change (SDC) of MRI-based cartilage thickness analysis in a large multicenter randomized controlled clinical trial of knee osteoarthritis

Test-retest reliability and smallest detectable change (SDC) of MRI-based cartilage thickness analysis in a large multicenter randomized controlled clinical trial of knee osteoarthritis

Validation of joint space narrowing on plain radiographs and its relevance to partial knee arthroplasty.

AimsTo explore the clinical relevance of joint space width (JSW) narrowing on standardized-flexion (SF) radiographs in the assessment of cartilage degeneration in specific subregions seen on MRI sequences in knee osteoarthritis (OA) with neutral, valgus, and varus alignments, and potential planning of partial knee arthroplasty.MethodsWe retrospectively reviewed 639 subjects, aged 45 to 79 years, in the Osteoarthritis Initiative (OAI) study, who had symptomatic knees with Kellgren and Lawrence grade 2 to 4. Knees were categorized as neutral, valgus, and varus knees by measuring hip-knee-angles on hip-knee-ankle radiographs. Femorotibial JSW was measured on posteroanterior SF radiographs using a special software. The femorotibial compartment was divided into 16 subregions, and MR-tomographic measurements of cartilage volume, thickness, and subchondral bone area were documented. Linear regression with adjustment for age, sex, body mass index, and Kellgren and Lawrence grade was used.ResultsWe studied 345 neutral, 87 valgus, and 207 varus knees. Radiological JSW narrowing was significantly (p < 0.01) associated with cartilage volume and thickness in medial femorotibial compartment in neutral (r = 0.78, odds ratio (OR) 2.33) and varus knees (r = 0.86, OR 1.92), and in lateral tibial subregions in valgus knees (r = 0.87, OR 3.71). A significant negative correlation was found between JSW narrowing and area of subchondral bone in external lateral tibial subregion in valgus knees (r = −0.65, p < 0.01) and in external medial tibial subregion in varus knees (r = −0.77, p < 0.01). No statistically significant correlation was found in anterior and posterior subregions.ConclusionSF radiographs can be potentially used for initial detection of cartilage degeneration as assessed by MRI in medial and lateral but not in anterior or posterior subregions.Cite this article: Bone Joint Res 2021;10(3):173–187.

The histopathology of the humeral head in glenohumeral osteoarthritis

ObjectiveThe histopathologic wear patterns in glenohumeral osteoarthritis (GOA) have not been described. The aims of the study were to a) describe the histopathology of humeral head wear patterns in patients with end-stage GOA and b) identify clinical and radiographic parameters that correlate with observed histopathological wear patterns. MethodsEighteen humeral heads from patients undergoing anatomic total shoulder arthroplasty for end-stage osteoarthritis were divided radially into eight wedge-shaped zones. Each zone was subdivided into central and peripheral regions. Histologic analysis included measurements of cartilage and subchondral bone plate thickness, subchondral bone area, and cartilage structure was scored using the Osteoarthritis Research Society (OARSI) and modified Mankin systems. Clinical variables including patient history, physical exam, functional evaluation, and radiographic assessments were evaluated for correlations with humeral head characteristics. ResultsOverall, humeral heads demonstrated a pattern of central and inferior cartilage damage, loss, and subchondral bone changes. However, within the group, composite maps of individual patient wear patterns demonstrated a sub-group of patients with a more focal inferior cartilage lesion. Overall, these more focal inferior lesions were associated with greater pre-operative range of motion (in both upper extremities), higher pre-operative SANE and ASES scores, female sex, non-dominant extremity, concentric wear patterns, and smaller inferior osteophytes. ConclusionHumeral head cartilage wear patterns in GOA include central and inferior cartilage damage and loss. A histopathological distinction was identified between patients with more focal versus diffuse wear, which may manifest clinically with preservation of function and range of motion, and with less profound radiographical changes.

Patterns of Articular Cartilage Thickness in Pediatric and Adolescent Knees: A Magnetic Resonance Imaging–Based Study

PurposeTo establish normative values for articular cartilage thickness in pediatric and adolescent knees using magnetic resonance imaging (MRI) and investigate for any associations with age and skeletal maturity.MethodsMRI scans were analyzed in patients 7 to 18 years old without osteochondral lesions, chondral wear/pathology, intra-articular fractures, or history of knee surgery. Measurements of articular cartilage thickness at the patella (medial facet, lateral facet, median ridge), femur (medial condyle, lateral condyle, lateral trochlea), and tibia (medial plateau, lateral plateau) were made on axial, coronal, and sagittal MRI. Descriptive statistics were used to calculate mean cartilage thickness by age and sex. Analysis of variance with repeated measures, analysis of covariance, independent samples t test, and linear regression were performed to determine differences in mean cartilage thickness by anatomic location, sex, physeal status, and age, respectively.ResultsA total of 240 knee MRI scans were included. Articular cartilage was thickest at the patella and did not vary with age or skeletal maturity. On the femur, articular cartilage was thickest at the lateral trochlea with mean cartilage thickness of 4.4 ± 1.4 mm in male patients and 3.6 ± 1.3 mm in female patients (P < .001). Patients with open distal femoral physes had significantly thicker cartilage at the medial femoral condyle, lateral femoral condyle, and lateral trochlea compared to patients with closing/closed physes (P < .001). Linear regression analysis revealed a significant inverse association between cartilage thickness at the femur and age.ConclusionsIn pediatric and adolescent knees, articular cartilage is thickest at the patella, where it does not strongly correlate with age. In contrast, there is a strong inverse association between increasing age and articular cartilage thickness of the distal femoral condyles.Clinical RelevanceThe longitudinal reference data presented in this study can aid in pre-operative interpretation of knee cartilage under pathologic conditions in pediatric and adolescent patients.

Comparison between 2D radiographic weight-bearing joint space width and 3D MRI non-weight-bearing cartilage thickness measures in the knee using non-weight-bearing 2D and 3D CT as an intermediary.

Background:In knee osteoarthritis, radiographic joint space width (JSW) is frequently used as a surrogate marker for cartilage thickness; however, longitudinal changes in radiographic JSW have shown poor correlations with those of magnetic resonance imaging (MRI) cartilage thickness. There are fundamental differences between the techniques: radiographic JSW represents two-dimensional (2D), weight-bearing, bone-to-bone distance, while on MRI three-dimensional (3D) non-weight-bearing cartilage thickness is measured. In this exploratory study, computed tomography (CT) was included as a third technique, as it can measure bone-to-bone under non-weight-bearing conditions. The objective was to use CT to compare the impact of weight-bearing versus non-weight-bearing, as well as bone-to-bone JSW versus actual cartilage thickness, in the knee.Methods:Osteoarthritis patients (n = 20) who were treated with knee joint distraction were included. Weight-bearing radiographs, non-weight-bearing MRIs and CTs were acquired before and 2 years after treatment. The mean radiographic JSW and cartilage thickness of the most affected compartment were measured. From CT, the 3D median JSW was calculated and a 2D projectional image was rendered, positioned similarly and measured identically to the radiograph. Pearson correlations between the techniques were derived, both cross-sectionally and longitudinally.Results:Fourteen patients could be analyzed. Cross-sectionally, all comparisons showed moderate to strong significant correlations (R = 0.43–0.81; all p < 0.05). Longitudinal changes over time were small; only the correlations between 2D CT and 3D CT (R = 0.65; p = 0.01) and 3D CT and MRI (R = 0.62; p = 0.02) were statistically significant.Conclusion:The poor correlation between changes in radiographic JSW and MRI cartilage thickness appears primarily to result from the difference in weight-bearing, and less so from measuring bone-to-bone distance versus cartilage thickness.

Ultrasonographic Measurement of the Distal Femoral Cartilage and Quadriceps Muscle Thickness in Hemiparetic Patients After Stroke and the Associations Functional Status

Ultrasonographic Measurement of the Distal Femoral Cartilage and Quadriceps Muscle Thickness in Hemiparetic Patients After Stroke and the Associations Functional Status

Accuracy of MRI-Based Talar Cartilage Thickness Measurement and Talus Bone and Cartilage Modeling: Comparison with Ground-Truth Laser Scan Measurements.

The purpose of this work was to compare measurements of talar cartilage thickness and cartilage and bone surface geometry from clinically feasible magnetic resonance imaging (MRI) against high-accuracy laser scan models. Measurement of talar bone and cartilage geometry from MRI would provide useful information for evaluating cartilage changes, selecting osteochondral graft sources or creating patient-specific joint models. Three-dimensional (3D) bone and cartilage models of 7 cadaver tali were created using (1) manual segmentation of high-resolution volumetric sequence 3T MR images and (2) laser scans. Talar cartilage thickness was compared between the laser scan- and MRI-based models for the dorsal, medial, and lateral surfaces. The laser scan- and MRI-based cartilage and bone surface models were compared using model-to-model distance. Average cartilage thickness within the dorsal, medial, and lateral surfaces were 0.89 to 1.05 mm measured with laser scanning, and 1.10 to 1.22 mm measured with MRI. MRI-based thickness was 0.16 to 0.32 mm higher on average in each region. The average absolute surface-to-surface differences between laser scan- and MRI-based bone and cartilage models ranged from 0.16 to 0.22 mm for bone (MRI bone models smaller than laser scan models) and 0.35 to 0.38 mm for cartilage (MRI bone models larger than laser scan models). This study demonstrated that cartilage and bone 3D modeling and measurement of average cartilage thickness on the dorsal, medial, and lateral talar surfaces using MRI were feasible and provided similar model geometry and thickness values to ground-truth laser scan-based measurements.

The Reliability of Ultrasound in the Assessment of Hyaline Cartilage in Rheumatoid Arthritis and Healthy Metacarpal Heads.

i) To assess the inter- and intra-observer reliability of ultrasound (US) in the evaluation of the hyaline cartilage (HC) of the metacarpal head (MH) in patients with rheumatoid arthritis (RA) and in healthy subjects (HS) both qualitatively and quantitatively. ii) To calculate the smallest detectable difference (SDD) of the MH cartilage thickness measurement. iii) To correlate the qualitative scoring system and the quantitative assessment. US examination was performed on 280 MHs of 20 patients with RA and 15 HS using a very high frequency probe (up to 22 MHz). HC status was evaluated both qualitatively (using a five-grade scoring system) and quantitatively (using the average value of the longitudinal and transverse measures). The HC of MHs from II to V metacarpophalangeal joint of both hands were scanned independently on the same day by two rheumatologists to assess inter-observer reliability. All subjects were re-examined using the same scanning protocol and the same US setting by one sonographer after a week to assess intra-observer reliability. The inter-observer agreement and intra-observer agreement were moderate to substantial (k = 0.66 and k = 0.73) for the qualitative scoring system and high (ICC = 0.93 and ICC = 0.94) for the quantitative assessment. The SDD of the MH cartilage thickness measurement was 0.09 mm. A significant correlation between the two scoring systems was found (r = -0.35; p < 0.001). The present study describes the main methodological issues of HC assessment. Using a standardized protocol, both the qualitative and the quantitative scoring systems can be reliable.

Efficacy of high intensity laser therapy in knee osteoarthritis: a double-blind controlled randomized study.

The aim of this study is to investigate the effectiveness of high intensity laser therapy on pain, functionality, flexion range of motion (FROM), and ultrasonographic cartilage measurement in patients with knee osteoarthritis. This study was designed as a double-blind randomized placebo-controlled study. Forty patients diagnosed with knee osteoarthritis according to the American College of Rheumatology criteria were included in the study. After obtaining written informed consent, patients were randomized into high intensity laser therapy (HILT) + exercise therapy (ET), and placebo laser (PL) + ET groups. Each patient was treated five sessions per week for 2 weeks. 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. The femoral cartilage thickness measurement was made ultrasonographically, and FROM was measured with goniometry. Statistically significant improvements were detected in VAS, WOMAC scores, femoral cartilage thickness, and FROM at the end of the treatment (in week 2) compared to the pre-treatment period in both groups (p < 0.05). There were significant decreases in the VAS and WOMAC scores of both groups in the 6th week compared to the pre-treatment period, and the results of the FROM and femur cartilage thickness measurements were increased at statistically significant levels (p < 0.05). The VAS and WOMAC scores were significantly lower in the 6th week in HILT + ET group compared to the PL + ET group (p < 0.05). Similarly, statistically significant increases were detected in the FROM and femur cartilage thickness measurements in HILT + ET group (p < 0.05). HILT + ET combination was more effective in KOA than the PL + ET combination. Key Points • HILT is an effective modality on pain, functional status and FROM in patients with KOA. • HILT is a modality that increases femoral cartilage thickness in patients with KOA.

Towards understanding mechanistic subgroups of osteoarthritis: 8-year cartilage thickness trajectory analysis.

Many studies have validated cartilage thickness as a biomarker for knee osteoarthritis (OA); however, few studies investigate beyond cross-sectional observations or comparisons across two timepoints. By characterizing the trajectory of cartilage thickness changes over 8 years in healthy individuals from the OA initiative data set, this study discovers associations between the dynamics of cartilage changes and OA incidence. A fully automated cartilage segmentation and thickness measurement method were developed and validated against manual measurements: mean absolute error = 0.11-0.14 mm (n = 4129 knees) and automatic reproducibility = 0.04-0.07 mm (n = 316 knees). The mean thickness for the medial and lateral tibia (MT, LT), central weight-bearing medial and lateral femur (cMF, cLF), and patella (P) cartilage compartments were quantified for 1453 knees at seven timepoints. Trajectory subgroups were defined per cartilage compartment such as stable, thinning to thickening, accelerated thickening, plateaued thickening, thickening to thinning, accelerated thinning, or plateaued thinning. For tibiofemoral compartments, the stable (22%-36%) and plateaued thinning (22%-37%) trajectories were the most common, with an average initial velocity (μm/month), acceleration (μm/month2 ) for the plateaued thinning trajectories LT:-2.66, 0.0326; MT:-2.49, 0.0365; cMF:-3.51, 0.0509; and cLF:-2.68, 0.041. In the patella compartment, the plateaued thinning (35%) and thickening to thinning (24%) trajectories were the most common, with an average initial velocity, acceleration for each -4.17, 0.0424; 1.95, -0.0835. Knees with nonstable trajectories had higher adjusted odds of OA incidence than stable trajectories: accelerated thickening, accelerated thinning, and plateaued thinning trajectories of the MT had adjusted odds ratio (OR) of 18.9, 5.48, and 1.47, respectively; in the cMF, adjusted OR of 8.55, 10.1, and 2.61, respectively.

Sonographic assessment of femoral cartilage thickness in healthy adults.

ObjectiveThis study was performed to obtain normative data of the distal femoral cartilage thickness in healthy adults by ultrasound.MethodsThis cross-sectional study included 72 healthy adults. The demographic characteristics of the participants were recorded, and the thickness of the femoral articular cartilage was measured using a 5- to 18-MHz linear probe.ResultsSignificant statistical difference towards the male side at left medial condyle (P = 0.001) and left lateral condyle (P = 0.009). Weakly positive statistical difference was noted towards the male side at right medial condyle (P = 0.06) and right lateral condyle (P = 0.07). The femoral cartilage thickness in the study participants did not correlate with weight, body mass index, and age (P >0.05). Positive statistical correlation with height noted in right medial condyle, right lateral condyle, right intercondylar area, and left medial condyle.ConclusionThis study increases the pool of normative data of femoral cartilage thickness measurements. Additionally, the findings of this study emphasize the fact that women have thinner cartilage than men in four of the studied parameters.

Ultrasonographic Measurement of Talar Cartilage Thickness in Patients With Cerebral Palsy.

Foot deformities are one of the most common musculoskeletal problems in children with cerebral palsy (CP). These deformities affect the walking ability and function of the patients. Talar cartilage is the hyaline joint cartilage of the tibiotalar joint that plantarflexes and dorsiflexes of the ankle. The aim of this study was to determine whether talar cartilage thickness was affected in children with ambulant diplegic CP. Forty patients with diplegic CP (19 boys, 21 girls) and 40 age-, sex-, and weight-matched healthy control subjects (20 boys, 20 girls) were included in the study. The demographic and clinical characteristics of the patients, including age, sex, and body mass index, were recorded. Patients were classified using the Gross Motor Function Classification System. A 12-MHz linear probe was used for ultrasonographic cartilage measurements at the tibiotalar joint according to European Musculoskeletal Ultrasound Study Group (EURO-MUSCULUS) and the Ultrasound Study Group in Physical and Rehabilitation Medicine (USPRM) scanning protocols. Mean talar cartilage thickness was significantly decreased in the CP group compared with the healthy control group (P < 0.001). There was a significant negative correlation between Gross Motor Function Classification System levels and talar cartilage thickness measurements (P < 0.001, Tb = -0.695). This study demonstrates that patients with CP have a thinner talar cartilage compared with healthy control subjects.

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

Background and objectiveArticular 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 methodsAn 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. Results100 subjects were included in the study. The average age was 20 years (± 2.5). The average BMI was 23kg/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. ConclusionsCartilage 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.

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

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. To evaluate distal femoral cartilage by shear wave elastography in patients with symptomatic knee osteoarthritis. 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. 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). Shear wave elastography seems to be a reliable, non-invasive, and acceptable method for the assessment of pathologic cartilage.

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

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

Finite element modeling of osteochondral explant impacts predicts locations of cell death

Purpose: Post-traumatic osteoarthritis (PTOA) is a subset of osteoarthritis initiated by an injury such as a blunt impact. However, the local tissue mechanics associated with the earliest stages of PTOA remain undefined. Computational modeling techniques such as finite element analysis provide a means to evaluate mechanical environments that are challenging to measure experimentally. The objective of this work was to compare specimen-specific stresses and strains computed using finite element analysis to confocal microscopy images of chondrocyte viability. Methods: Four viable osteochondral explants (25 mm x 25 mm x 15 mm) were harvested from the tibial plateau of healthy bovine stifle joints (knee). Once removed, the explants were washed twice in HBSS, cultured in normal media (45% DMEM, 45% F12, 10% fetal bovine serum, 100 U/mL penicillin, 100 μg/mL streptomycin, and 2.5 μm/mL amphotericin B) and incubated at 37°C, 5% CO2, and 5% O2. The following day a surface scan of the articular surface of each explant (EinScan Pro 2X Pro; Shining 3D) and ultrasound measurements (Olympus 35DL) of cartilage thickness were acquired. Next, the explants were subject to a 2 J/cm2 impact using a 6 mm flat, beveled stainless-steel platen. After impact, the samples were placed in fresh porcine media and returned to the incubator for 24 h. Cartilage explants were cut with an Isomet 1000 (Buehler, Lake Bluff, IL) slightly off center of the impact and faced by trimming 0.5 mm of the cartilage with a scalpel. These provided a coronal plane cross-section of the explant through the center of the impact site. The explants were washed in phenol red free DMEM/F12 media and stained for 30 min in the incubator with 1 mg/mL Calcein Green AM and 200 nM MitoTracker Deep Red (Life Technologies, Waltham, MA). The samples were then washed and imaged on an Olympus FV1000 (Shinjuku, Japan) confocal microscope. Images were acquired on either edge of the impact, 1 mm inside each edge of the impact site, and in the center of the impact (Figure 1) using a 10X objective lens. An additional top-down view of the articular surface was acquired. Specimen-specific finite element models were generated using the surface scan, cartilage thickness measurements, and geometric measurements of each explant. Cartilage was modeled as hyperelastic with a first-order Ogden strain energy potential. Acceleration of the impact platen was measured (PCB Piezotronics accelerometer), and double integration was used to calculate platen displacement at max tissue compression and impact force. von Mises stress and normal z strain values were compared from corresponding nodes within confocal images (Figure 2). Cell death in the superficial zone and deeper regions of cartilage was assessed. Results: Cell death was present in the superficial zone in 4/4 peripheral edge locations, 3/4 locations interior to the impactor edge and 3/4 of the middle sites. There was no superficial cell death on the central edge of the impact zone. Locations experiencing > 40% strain were associated with high levels of cell death in the superficial zone. When strains exceeded 60%, cell death extended into the deeper zones of the cartilage. It was noteworthy that the highest strains were found at the 1-mm interior to the impact platen edge on all specimens. Von Mises stresses were consistently &gt 30 MPa on the edge of the impact site; however, no obvious relationships were identified between von Mises values and cell death in the superficial, middle, or deep zones. Conclusions: We found strong associations between cartilage strain and chondrocyte death. The highest normal z strain occurs just interior to the beveled edge of the impact platen, and not on the peripheral-most edge of the impact platen. While we did find associations between locations of elevated stress, strain, and cell death, the magnitudes of those values remain to be validated. While important, cell death is a relatively broad measure of injury and associations between cellular health and function and these mechanical measures should be explored.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

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

Cartilage diameter evaluation is critical for cartilage assessment. Magnetic resonance imaging (MRI) is the gold standard toolin cartilage evaluation. This observational and analytical study was designed to answer the question of whether there is arelationship between MRI and ultrasound in measuring cartilage thickness in the medial femoral condyle. The current study wasconducted at the Radiology Department of Rasole-Akram Hospital, Tehran, Iran, between March and May 2020. The samplesize was 18 people. The mean cartilage thickness of the left medial femoral cartilage was measured by T1 weighted MRI andultrasound from transverse, anterior, middle, and posterior medial femoral regions in nine healthy females with a mean ± stddeviation as indicated below: thickness = 1.6 ± 0.04 m, weight = 55.3 ± 4.3 kg, age = 21.7 ± 0.8 years.Additionally, nine healthy males with thickness = 1.80 ± 0.02 m, weight = 78.6 ± 11.1 kg, age = 22.4 ± 0.7 years were alsoincluded. Pearson and Bland–Altman plots were used for correlations and agreements. Anterior longitudinal ultrasoundthickness measures were significantly positively correlated with MRI anterior (r = 0.93, p = 0.00001), transverse ultrasoundwith MRI anterior (r = 0.87 p = 0.0369), middle longitudinal ultrasound with MRI anterior (r = 0.87 p = 0.00002), and transverseultrasound and MRI middle (r = 0.87 p = 0.00001).Agreement in all aspects was good except between the anterior longitudinal ultrasound and MRI posterior. There was a goodabsolute agreement between corresponding measurements done by ultrasound and MRI. The results suggest that ultrasound maybe a good clinical tool for assessing relative cartilage thickness in medial femoral regions.

Changes in medial compartment loading and articular cartilage thickness 24 months after limb realignment surgery in the operative and non-operative limbs

Purpose: High tibial osteotomy (HTO) is a limb realignment surgery for patients with medial compartment knee osteoarthritis (OA) and varus alignment. The surgery is proposed to improve aberrant knee joint loading and thereby alter disease progression. The purpose of the present study was to quantify and compare changes in MRI-based measures of medial articular cartilage thickness and 3D gait analysis-based measures of medial-to-lateral knee load distribution preoperatively, and at 12 and 24 months postoperatively in both the operative and non-operative limbs.

ARTICULAR CARTILAGE THICKNESS IN PEDIATRIC AND ADOLESCENT KNEES DECREASES WITH AGE AND SKELETAL MATURITY: IMPLICATIONS FOR OSTEOCHONDRAL GRAFTING PROCEDURES

Background:Quantifying native cartilage thickness in pediatric and adolescent knees can help match donor and recipient sites for articular cartilage restoration procedures such as osteochondral autograft transplantation (OATS) and osteochondral allograft transplantation (OCA).Hypothesis/Purpose:The purpose of the current study was to quantify articular cartilage thickness in pediatric and adolescent knees using magnetic resonance imaging (MRI). We hypothesized that cartilage thickness is inversely correlated with skeletal maturity and age.Methods:One hundred and twenty MRI scans were evaluated in a cohort of patients 9 to 18 years old without osteochondral lesions, chondral wear or pathology, intraarticular fractures, history of knee surgery, or inflammatory arthropathy. Measurements of articular cartilage thickness at the medial femoral condyle, lateral femoral condyle, lateral trochlea, and patella were made on axial, coronal, and sagittal MRI scans (Figure 1). Skeletal maturity was categorized as ‘open’, ‘closing’, or ‘closed’ based on the status of the proximal tibial and distal femoral growth plates. Descriptive statistics was used to evaluate cartilage thickness by age and sex. Independent samples t-test, analysis of variance (ANOVA), and linear regression were performed to investigate for associations with sex, skeletal maturity, and age.Results:On the femur, cartilage was thickest at the lateral trochlea with mean articular thickness of 4.2 ± 1.4 mm in males and 3.6 ± 1.3 mm in females (p=0.015) (Table 1). Skeletally immature patients with open physes had significantly thicker cartilage at the medial femoral condyle, lateral femoral condyle, and lateral trochlea compared to patients with closing and closed physes (Figure 2). Linear regression analysis also revealed a significant association between femoral cartilage thickness and age (Figure 3). Age explained 63% of the variance at the medial femoral condyle (B=6.1, p<0.001), 64% of the variance at the lateral femoral condyle (B=4.9, p<0.001), and 68% of the variance at the lateral trochlea (B=8.2, p<0.001) (Table 2). In contrast, cartilage thickness at the patella did not significantly vary by age, sex, or skeletal maturity (Figures 2 and 4).Conclusion:There is a strong inverse association between increasing age and cartilage thickness of the femoral condyles and lateral trochlea. In particular, pediatric knees demonstrate relatively thick cartilage at the lateral trochlea that decreases with age. This information will help surgeons understand recipient site anatomy and identify appropriate donor site tissue for articular cartilage restoration procedures such as OATS and OCA in children and adolescents.Tables:Table 1.Mean articular cartilage thickness of the femur and patellaCombined (n=120)Male(n=40)Female(n=60) p valueMedial femoral condyle3.2 ± 1.03.5 ± 1.02.9 ± 0.80.001Lateral femoral condyle2.8 ± 0.72.9 ± 0.72.7 ± 0.70.056Lateral trochlea3.9 ± 1.44.2 ± 1.43.6 ± 1.30.015Median ridge of patella4.2 ± 0.94.4 ± 0.94.1 ± 0.90.080Medial facet of patella4.7 ± 1.04.8 ± 1.04.6 ± 0.90.320Lateral facet of patella4.6 ± 0.84.7 ± 0.84.5 ± 0.80.185Table 2.Linear regression of articular cartilage thickness of the femur and patella by ageR2 B p valueMedial femoral condyle0.636.1<0.001Lateral femoral condyle0.644.9<0.001Lateral trochlea0.688.2<0.001Median ridge of patella0.024.80.090Medial facet of patella0.045.50.032Lateral facet of patella0.0014.50.741Figures:Figure 1.Measurements of patellofemoral articular cartilage thickness Measurements of articular cartilage thickness were made on (A) coronal, (B, C) sagittal, and (D) axial magnetic resonance imaging (MRI) of the knee. For the medial femoral condyle, cartilage thickness was measured at five regions: midpoint of the medial condyle (MFC) and midpoints of Cahill zones 1 (MID1), 2 (MID2), B (MIDB) and C (MIDC). Similarly, measurements of cartilage thickness of the lateral femoral condyle were made at the midpoint of the lateral condyle (LFC) and midpoints of Cahill zones 4 (MID4), 5 (MID5), B (MIDB), and C (MIDC). Measurement of the lateral trochlea was made at midpoint of Cahill zone A (MIDA). Measurements on the patella were made at the midpoint of the medial facet (MF), midpoint of the lateral facet (LF), and the median ridge (MR) on axial and sagittal MRI scans. Figure 2.Mean articular cartilage thickness of the femur and patella by growth plate statusFigure 3.Mean articular cartilage thickness of the femur by ageFigure 4.Mean articular cartilage thickness of the patella by age

Ultrasonographic measurement of femoral cartilage thickness in type II diabetic patients.

The aim of this study is to compare the distal femoral cartilage thickness of patients with type II diabetes mellitus with those of healthy subjects using ultrasonography. The study comprised 34 patients and 36 healthy subjects. Demographic characteristics of all the participants were recorded. The thickness of the femoral articular cartilage was measured using a 5-18MHzlinearprobe.Measurements were performed bilaterally from three points (intercondylar area, medial condyle, and lateral condyle). No significant difference could be found between patients and healthy subjects. Two demographic characteristics correlated positively with diabetic patients.