Ultrasonographic evaluation in symptomatic knee osteoarthritis: clinical and radiological correlation

Assessment of validity, reliability, and feasibility of OMERACT ultrasound knee osteoarthritis scores in Egyptian patients with primary knee osteoarthritis

BACKGROUND

Ultrasound (US) can evaluate all joint components affected by knee osteoarthritis (KOA); however, standardized scoring of US-detected pathology is needed to improve its diagnostic and monitoring capabilities.

OBJECTIVES

To examine the validity, reliability, and feasibility of the Outcome Measures in Rheumatology (OMERACT) ultrasound scoring for KOA, comparing with clinical and radiography measures, using predefined cutoff values.

METHODS

This cross-sectional study included 75 Egyptian patients with primary KOA. All patients had Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, bilateral knee radiography, and ultrasonography. Inter-observer reliability of ultrasound was evaluated in 30 knees by another newly trained operator.

RESULTS

Most of the OMERACT-US KOA scores showed significant associations with WOMAC clinical scores, except for femoral cartilage damage and effusion. The synovitis score was significantly associated with WOMAC-pain score (p-value 0.046), while medial meniscus extrusion (MME) and medial osteophytes were significantly associated with WOMAC-stiffness score (p-value 0.009 and 0.023, respectively). MME and synovitis were significantly associated with WOMAC-physical score (p-value 0.035 and 0.020, respectively). The ultrasound scores also showed a strong correlation with radiographic scoring. Inter-observer reliability ranged from moderate to excellent agreement (k = 0.58 to k = 0.83); it was highest for lateral osteophytes (k = 0.83), good agreement for synovitis (k = 0.72), any osteophytes (k = 0.71), damage of femoral cartilage (k = 0.70), and moderate agreement for medial osteophytes (k = 0.58) and MME (k = 0.59).

CONCLUSION

OMERACT-US scoring system for KOA demonstrated validity, reliability, and feasibility for evaluating both structural and inflammatory components. Using cutoff values improved the scoring reliability for osteophytes and MME. Key Points • OMERACT-US scores provide a valid assessment of inflammatory and structural components of knee osteoarthritis. • The following changes may improve the performance of the OMERACT-US scores. a. The binary score for effusion and synovial hypertrophy can be omitted, as they have no added value. b. A semi-quantitative grading for effusion may capture the impact of effusion on clinical outcomes. c. Added cutoff values to score medial meniscal extrusion, osteophytes, and pathological effusion improved the respective scores' reliability. d. Applying the updated OMERACT definition of synovitis. • OMERACT-US scores are reliable to be used with a newly trained operator, particularly when cutoff values are included, and proper training time is provided. • The OMERACT-US score is feasible to be used in clinical practice, as the time taken to perform was short, even for a newly trained operator.

Relationship between ultrasonographic findings and subscales of the Knee Injury and Osteoarthritis Outcome Score in patients with early knee osteoarthritis: a multicenter study

PURPOSE

To characterize the ultrasonographic findings of patients with early knee osteoarthritis (KOA) and determine which findings were associated with the Knee Injury and Osteoarthritis Outcome Score (KOOS) subscale.

METHODS

The study included 98 knees (35 men, 63 women, 60.3 ± 11.5 years) diagnosed with early KOA with no major deformity radiographically, but with pain during activity and tenderness in the medial knee. Synovial hyperplasia in the suprapatellar bursa, knee joint effusion, horizontal tear of the medial meniscus (MM), osteophytes of the medial condyle of the femur and tibia, blood flow signals in the synovium of the suprapatellar bursa, medial collateral ligament bursa, infrapatellar fat pad, MM extrusion (MME) in the supine and upright positions, and the amount of change in MME were observed using ultrasonography.

RESULTS

Correlations (p < 0.05) were found between the presence of synovial hyperplasia of the suprapatellar bursa (r<-0.20) and amount of MME in the upright position (r< - 0.24) and all KOOS subscales. Presence of joint effusion and the four KOOS subscales except quality of life (QOL) were correlated (p < 0.05). Partial correlation coefficients showed correlations (p < 0.05) between knee joint effusion and symptoms (r = 0.299) and activities of daily living (ADL) (r = 0.254) of the KOOS subscales, and between MME in the upright position and symptoms (r= - 0.263), pain (r= - 0.256), and ADL (r= - 0.212).

CONCLUSION

Quality and difficulty of life of patients with early KOA may be influenced by synovial hyperplasia in the suprapatellar bursa, joint effusion, and MME values in the upright position. Among them, synovial hyperplasia of the suprapatellar bursa and amount of MME in the upright position were independently associated with the KOOS subscales.

The ultrasound assessment of osteoarthritis: the current status

Traditionally, osteoarthritis (OA) is diagnosed with the clinical examination supplemented by the conventional radiography (CR). In the research literature, the role of ultrasound (US) imaging in the diagnostics of OA has risen steadily during the last two decades. US imaging is cheap and globally widely available often already in primary healthcare. Here, we reviewed the most essential US literature focusing on OA diagnostics and progression prediction using the various search engines. Starting from the year 2000, our search provided 1 445 journal articles. After reviewing the abstracts, 89 articles were finally included. Most of the reviewed articles focused on the imaging of knee and hand OA, whereas only a minority dealt with the imaging of hip, ankle, midfoot, acromioclavicular, and temporomandibular joints. Overall, during the last 20 years, the use of US imaging for OA assessment has increased in the scientific literature. In knee and hand joints, US imaging has been reported to be a promising tool to evaluate OA changes. Furthermore, the reproducibility of US as well as its association to MRI findings are excellent. Importantly, US seems to even outperform CR in certain aspects, such as detection of osteophytes, joint inflammation, meniscus protrusion, and localized cartilage damage (especially at the medial femoral condyle and sulcus area). Based on the reviewed literature, US can be truly considered as a complementary tool to CR in the clinical setup for OA diagnostics. New technical developments may even enhance the diagnostic value of the US in the future.

Clinical Evidence Regarding the Dynamic of Baker Cyst Dimensions after Intermittent Vacuum Therapy as Rehabilitation Treatment in Patients with Knee Osteoarthritis

The Baker cyst (BC), also known as the popliteal cyst or parameniscal cyst, is a fluid-filled sac that normally develops in the back of the knee, between the semimembranosus and medial head of the gastrocnemius. We aimed to evaluate the effectiveness of physiotherapy (10 days of treatment) that associates intermittent vacuum therapy (IVT) on the lower limbs in the treatment of the BC, respectively, in its size reduction. Sixty-five patients with knee osteoarthritis using Kellgren-Lawrence criteria and the presence of BC (ultrasonography evaluation), were divided into the Control and Vacuum groups. We collected the following features: sex, age, level of education, occupation, environment, body mass index, Knee Injury and Osteoarthritis Outcome Score, Western Ontario, and McMaster Universities Osteoarthritis Index, the Functional Independence Measurement, the Fall Risk Score, and the Visual Analog Scale were recorded at baseline and after 10 days. Both groups are similar in terms of demographic features. Regarding the clinical functional parameters, the results elicit a statistically significant change in all parameters between admission and discharge, including the echo volume at BC. Physical medicine and rehabilitation increase the autonomy of patients with BC. Clinical-functional improvement begins in the first 10 days of complex rehabilitation treatment; it is statistically significant and is not different between the two groups, which brings an additional argument for the effectiveness of conservative therapy in the treatment of BC. Although IVT has not demonstrated its superiority over classical balneo-physical therapy, additional research, and long-term monitoring are needed to provide additional arguments regarding this aspect.

Ultrasound Evaluation of Knee Osteoarthritis

While radiographs and magnetic resonance imaging (MRI) have long been used in the assessment of osteoarthritis (OA), ultrasound imaging has been rapidly accepted by musculoskeletal providers in both the assessment and treatment of OA. A limiting factor in the use of ultrasound is the proper training required by the user for results to be reliable and reproducible. A standardized ultrasound protocol can potentially address this limiting factor. The critical information to consider in a standardized protocol include proper patient positioning, probe alignment, probe orientation, and identification of the appropriate anatomic landmarks. The outlined protocol considers these factors with the purpose of providing a step-by-step method to assess and monitor knee OA.

Femoral Cartilage Thickness in Knee Osteoarthritis Patients and Healthy Adults: An Ultrasound Measurement Comparison

Background

Currently, conventional radiography is still widely used to diagnose knee osteoarthritis and assess the grade according to Kallgren and Lawrence's criteria. Ultrasound is a simple, inexpensive, noninvasive, and dynamic modality for evaluating femoral cartilage (FC) thickness. This study aims to measure the FC thickness in knee osteoarthritis (OA) patients and compare it to healthy adults using ultrasound assessment.

Methods

An observational study with a cross-sectional design was conducted at the Department of Physical Medicine and Rehabilitation of Hajj General Hospital, Surabaya, Indonesia, from May to July 2022. Participants radiologically diagnosed with OA were included in the study and assigned to the OA group. Meanwhile, healthy adults without knee symptoms were included in the control group. FC thickness was measured using ultrasound scans at three sites: medial condyle (MC), intercondylar (IC), and lateral condyle (LC) on both sides of the knee.

Results

The mean age in the OA and control groups was 61.03 ± 8.6 and 33.93 ± 14.7 years, respectively. Most participants in both groups were female. The OA group exhibited a thinner FC (1.49-1.63 mm) than the control group (1.68-1.87 mm). There was a significant difference in the mean of the right and left MC in both groups (p < 0.05) but no significant difference in the IC and LC.

Conclusion

OA patients exhibited a thinner FC than healthy adults in the control group. There was a significant difference in the mean thickness of the MC between groups.

Clinical significance and management of meniscal extrusion in different knee pathologies: a comprehensive review of the literature and treatment algorithm

The menisci are crescent-shaped, fibrocartilaginous structures that play a crucial role in the load transition and distribution of the contact forces along the tibiofemoral articulation. Meniscal extrusion (ME) is a radiological finding, especially in magnetic resonance imaging (MRI) scans, for which there has been growing interest in recent years. ME, in the coronary plane, is defined as the maximum distance of the most distal end of the meniscus from the border of the tibial plateau, where the tibial eminences are the most prominent, without taking into account the osteophytes. Although there is still controversy in the literature in respect of the optimal cutoff value, a threshold of 3 mm is considered significant. ME has no specific clinical finding or sign and it is encountered in many knee pathologies. It is associated with either rapidly progressive knee osteoarthritis or early onset of knee osteoarthritis and increased morbidity. In this review, we delineate the clinical significance of ME in various knee pathologies, as well as when, why and how it should be managed. To the best of our knowledge, this is the first study to elaborate on these topics.

Ultrasonography findings in knee osteoarthritis: a prospective observational cross-sectional study of 100 patients

Worldwide, knee osteoarthritis (KOA) accounts for 2.2% of total years lived with disability. There is a low correlation between joint tissue damage and pain intensity. Periarticular structures may be involved and cannot be identified in X-rays. To describe the main ultrasonography (USG) changes in symptomatic patients with primary KOA; to correlate the number of USG findings with KOA severity assessed by Kellgren and Lawrence (K&L) radiological scores, with pain intensity measured by a visual analogue scale (VAS) and with functioning scores assessed with the Timed up and go test (TUG) and Western Ontario and McMaster Universities (WOMAC) questionnaire. 100 patients with primary symptomatic KOA were assessed with X-ray and USG. Quantitative and qualitative analyses were evaluated in a systematic manner. The most frequent findings were joint effusion, pes anserinus bursitis, quadriceps tendon enthesopathy, popliteal cyst, iliotibial band tendinitis and patellar tendinitis. Pearson's correlation analysis demonstrated a significant moderate positive association between VAS scores and the number of USG findings (r = 0.36; p < 0.0001). The number of USG findings was different between K&L grades I and III (p = 0.041), I and IV (p < 0.001), and II and IV (p = 0.001, analysis of variance with Bonferroni correction). There was significant association between number of USG findings and TUG (r = 0.18; p = 0.014) and WOMAC scores for pain (r = 0.16; p < 0.029) and physical function domains (r = 0.16; p < 0.028). The most frequent USG finding was joint effusion. Periarticular structures should be explored as potential sources of pain and disability.

Imaging of knee osteoarthritis: A review of current evidence and clinical guidelines

BACKGROUND

Knee osteoarthritis (OA) is one of the most common and debilitating degenerative joint diseases worldwide. While radiography is the most commonly used imaging modality, it is associated with drawbacks which newer modalities such as magnetic resonance imaging (MRI) and ultrasound could overcome. Nevertheless, the role of imaging in clinical practice and research in knee OA has not been clearly defined. Furthermore, guidelines on imaging in knee OA from different authoritative bodies have not been compared in previous studies. Therefore, the present review aims to summarise existing evidence and compare guidelines on the use of different imaging modalities in evaluating knee OA.

METHODS

This is a narrative review based on a search of published clinical guidelines and the PubMed database for articles published between 1 January 1990 and 31 May 2020.

RESULTS

There is no broad consensus on the value of imaging in patients with typical OA presentation. If imaging is required, current evidence and clinical guidelines support the use of radiography and MRI as first- and second-line diagnostic modalities respectively. Since radiographic OA features have limited sensitivity and do not manifest in early stages, MRI is the preferred option for whole-joint evaluation in OA research. Discrepancies exist regarding the use of alternative imaging modalities including ultrasound, computed tomography and nuclear medicine.

CONCLUSION

Radiography and MRI are the imaging modalities of choice. Other modalities have their respective advantages, and more research is warranted for the standardisation of image acquisition and interpretation methodology, in order to evaluate their validity, reliability and responsiveness in OA research.

Ultrasonographic Evaluation of Osteoarthritis-affected Knee Joints: Comparison with Kellgren-Lawrence Grading and Pain Scores

BACKGROUND

The objective was to compare ultrasonographic findings with clinical and radiographic findings in osteoarthritis (OA)-affected knee joints.

METHODS

This prospective study was conducted in Subharti Medical College, Meerut, after getting clearance from the ethical committee. Eighty-five symptomatic knees fulfilling American College of Rheumatology criteria for OA were included in the study. Patients with trauma, inflammatory, and infective conditions of the knee and with a history of intra-articular interventions and surgery were excluded. Demographic data, body mass index (BMI), visual analog scale (VAS), and Western Ontario and McMaster Universities Arthritis (WOMAC) questionnaire score were obtained. Kellgren-Lawrence (K-L) score was obtained on radiography. Ultrasonographic findings which were recorded include effusion, meniscal extrusion, femorotrochlear cartilage grading, maximum length of osteophytes at medial and lateral compartments, and presence or absence of Baker cyst.

RESULTS

A total of 85 consecutive symptomatic knees were examined. The male: female ratio was 22:63, with a mean age of 54.52 ± 9.44 years, mean duration of disease of 24.24 ± 19.14 months, mean BMI of 28.91 ± 3.69 kg/m2, and mean score of VAS and WOMAC pain scale of 6.27 ± 1.45 and 62.45 ± 10.96, respectively. K-L grading of 1, 2, 3, and 4 was reported in 12.9%, 21.2%, 25.9%, and 40% of the knees, respectively. The mean VAS score and WOMAC score showed statistically significant correlation with KL grading (P < 0.05). Knees with the presence of osteophytes, medial meniscal extrusion, effusion, and medial femoral trochlear cartilage grading showed statistically significant correlation with VAS and WOMAC scores (P < 0.05). However, the correlation was not significant for lateral meniscus extrusion and lateral femoral trochlear cartilage grading.

CONCLUSION

Our study found that K-L grading and few ultrasonographic criteria showed a significant positive correlation with pain scores, while few other ultrasonographic criteria did not. Both imaging modalities are complementary to each other, rather than one being superior to the other.

Sonographic assessment of femoral cartilage thickness in healthy adults

OBJECTIVE

This study was performed to obtain normative data of the distal femoral cartilage thickness in healthy adults by ultrasound.

METHODS

This 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.

RESULTS

Significant 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.

CONCLUSION

This 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.

Association between grayscale sonographic and clinical findings in severe knee osteoarthritis

PURPOSE

To assess whether ultrasonographic (US) findings associate with clinical findings in severe knee osteoarthritis (OA). Association of US findings with side-of-knee pain and inter-reader agreement of knee US were also evaluated.

METHODS

One-hundred-two patients (in total 123 knees) with severe knee OA were recruited for this cross-sectional study. US was performed by a single observer, and on 53 knees by two independent observers to assess inter-reader reliability. Preoperative clinical data was available for 69 knees. Cutoff values were applied to dichotomize US and clinical findings. The Chi-square test, Mann-Whitney test, and prevalence- and bias-adjusted kappa (PABAK) were applied for statistical analyses.

RESULTS

Seven of 99 associations tested were statistically significant. Associations were observed between range of flexion and lateral femoral (P = .009) and tibial (P = .001) osteophytes, mediolateral instability and damage to the lateral femoral cartilage (P = .014) and damage to the lateral meniscus (P = .031), and alignment and damage to the lateral femoral cartilage (P < .001), lateral tibial osteophytes (P = .037), and damage to the lateral meniscus (P < .001). A strong association was observed between medial-sided pain and same-sided cartilage damage and osteophytes (P < .001). That inter-reader agreement was excellent on the medial side of the knee joint (PABAK = 0.811-0.887).

CONCLUSIONS

US findings show a rather poor association with clinical OA findings. Inter-reader agreement of knee US is excellent on the medial side.

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.

Effectiveness of Therapeutic Ultrasound on Clinical Parameters and Ultrasonographic Cartilage Thickness in Knee Osteoarthritis: A Double-Blind Trial

Objective:

A double-blind placebo-controlled randomized study was conducted to assess the effectiveness of therapeutic ultrasound (US) in knee OA.

Patients and Methods:

Thirty-three patients (mean age 54.7 ± 14.7) were randomized to receive either continuous US (n = 15) or sham US (n = 18) as a placebo. Continuous ultrasonic waves with 1 MHZ frequency and 1 watt/cm² power were applied for 5 min for 10 sessions. The primary outcome was pain on movement assessed by visual analog scale (VAS). The secondary outcomes were WOMAC scores and measurements of distal femoral cartilage thickness by imaging US.

Results:

Both groups showed reduced knee pain on movement following intervention. The VAS measurements improved significantly both in the treatment and the placebo group patients (P < 0.05 and P < 0.05). WOMAC scores improved statistically significant in all domains (pain, stiffness, physical function, and total score) in the treatment group (P < 0.05). All domains of WOMAC score showed statistically significant change when compared with the placebo group (P < 0.05). There was no change in the cartilage thickness measurements of medial femoral condyle, lateral femoral condyle, and intercondylar area in both groups after intervention.

Conclusion:

Results suggest that US is effective treatment modality in pain relief and improvement of function in patients with knee OA; however, US had no effect on cartilage repair.

Structure-symptom relationship with wide-area ultrasound scanning of knee osteoarthritis

The aetiology of knee pain in osteoarthritis (OA) is heterogeneous and its relationship with structural changes and function is unclear. Our goal was to determine the prevalence of wide-area scanned ultrasound-defined knee OA structural features and their association with pain and functional impairment in 79 symptomatic and 63 asymptomatic subjects. All subjects underwent ultrasound knee wide-area scanning and the severity of articular cartilage degeneration, the presence and size of osteophytes, and meniscal extrusion were evaluated. Subjects filled in a self-administrated questionnaire on present knee pain, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) on clinical symptoms and function over the past week. Cartilage changes were the most prevalent followed by lateral meniscal extrusion, osteophytes and medial meniscal extrusion. The global femoral cartilage grade associated strongly with pain and the WOMAC index. Site-specifically, early medial cartilage changes and thinning in sulcus and lateral site were associated with symptoms. The presence of femoral lateral osteophytes was also associated with both outcomes. Using the novel wide-area ultrasound scanning technique, we were able to confirm the negative impact of femoral cartilage OA changes on clinical symptoms. Presence, not necessarily size, of lateral femoral osteophytes was also associated with increased pain and disability.

Synovial changes detected by ultrasound in people with knee osteoarthritis - a meta-analysis of observational studies

OBJECTIVES

To examine the prevalence of synovial effusion, synovial hypertrophy and positive Doppler signal (DS) detected by ultrasound (US) in people with knee osteoarthritis (OA) and/or knee pain compared to that in the general population.

METHOD

A systematic literature search was undertaken in Medline, EMBASE, Allied and Complementary Medicine, PubMed Web of Science, and SCOPUS databases in May 2015. Frequencies of US abnormalities in people with knee OA/pain, in the general population or asymptomatic controls were pooled using the random effects model. Publication bias and heterogeneity between studies were examined.

RESULTS

Twenty four studies in people with knee pain/OA and five studies of the general population or asymptomatic controls met the inclusion criteria. The pooled prevalence of US effusion, synovial hypertrophy and positive DS in people with knee OA/pain were 51.5% (95% CI 40.2 to 62.8), 41.5% (26.3-57.5) and 32.7% (8.34-63.24), respectively, which were higher than those in the general population or asymptomatic controls (19.9% (95%CI 7.8-35.3%), 14.5% (0-58.81), and 15.8 (3.08-35.36), respectively). People with knee OA (ACR criteria or radiographic OA) had greater prevalence of US abnormalities than people with knee pain (P = 0.037, P = 0.010 and P = 0.009, respectively).

CONCLUSIONS

US detected effusion, synovial hypertrophy and DS are more common in people with knee OA/pain, compared to the general population. These abnormalities relate more to presence of OA structural changes than to pain.

Comparison of the efficacy of physical therapy and corticosteroid injection in the treatment of pes anserine tendino-bursitis

[Purpose] The aims of this study were twofold. The first was to compare the functional capacity and pain of patients with knee osteoarthritis (KOA), with or without pes anserine tendino-bursitis (PATB). The second is to compare the efficacy of two treatment methods (physical therapy and corticosteroid injection) for patients with PATB. [Subjects and Methods] Sixty patient with KOA and PATB (Group 1) and 57 patients with KOA but without PATB (Group 2) were enrolled in the study. The patients' visual analog scale (VAS), Western Ontario and McMaster Universities osteoarthritis index (WOMAC) scores and three-meter timed-up and go scores were measured. The PATB group was randomly divided into two groups (Group A and B). Physical therapy (PT) modalities were applied to the first group (Group A), and the second group (Group B) received corticosteroid injections to the pes anserine area. Eight weeks later, patients' parameters were measured again. [Results] Initial WOMAC scores and timed up-and-go times were significantly higher in Group 1 than in Group 2. Both treatments resulted in significant improvements in all measured parameters, but no significant difference was detected between Group A and B. [Conclusion] Patients with PATB tend to have more severe pain, more altered functionality, and greater disability than those with KOA but without PATB. Both corticosteroid injection and PT are effective methods of treatment for PATB. Injection therapy can be considered an effective, inexpensive and fast therapeutic method.

The Effects of Smoking on Ultrasonographic Thickness and Elastosonographic Strain Ratio Measurements of Distal Femoral Cartilage

Although adverse effects of smoking on bone health are all well known, data on how smoking interacts with cartilage structure in otherwise healthy individuals remains conflicting. Here, we ascertain the effects of cigarette smoking on sonoelastographic properties of distal femoral cartilage in asymptomatic adults. Demographic characteristics and smoking habits (packets/year) of healthy volunteers were recorded. Medial, intercondylar, and lateral distal femoral cartilage thicknesses and strain ratios on the dominant extremity were measured with ultrasonography (US) and real time US elastography. A total of 88 subjects (71 M, 17 F; aged 18–56 years, N = 43 smokers and N = 45 nonsmokers) were evaluated. Mean amount of cigarette smoking was 10.3 ± 8.9 (1–45) packets/year. Medial, intercondylar and lateral cartilage were thicker in smokers than nonsmokers (p = 0.002, p = 0.017, and p = 0.004, respectively). Medial distal femoral cartilage strain ratio was lower in smokers (p = 0.003). The amount of smoking was positively correlated with cartilage thicknesses and negatively correlated with medial cartilage strain ratios (p < 0.05). Femoral cartilage is thicker in smokers but has less strain ratio representing harder cartilage on the medial side. Future studies are needed to understand how these structural changes in the knee cartilage should be interpreted with regard to the development of knee osteoarthritis in smokers.

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.

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.

Osteochondral regeneration with a novel aragonite-hyaluronate biphasic scaffold: up to 12-month follow-up study in a goat model

BACKGROUND

The regeneration of articular hyaline cartilage remains an elusive goal despite years of research. Recently, an aragonite-hyaluronate (Ar-HA) biphasic scaffold has been described capable of cartilage regeneration over a 6-month follow-up period. This study was conducted in order to assess the fate of the regenerated osteochondral tissue in a 12-month-long validated caprine model.

HYPOTHESIS/PURPOSE

The hypothesis was that the implantation of the Ar-HA implant leads to tissue regeneration and maturation.

STUDY DESIGN

A two-arm caprine model of a critical osteochondral defect compares the fate of acute osteochondral defects (group A) to Ar-HA implanted defects (group B).

METHODS

Critical 6 mm in diameter and 10-mm in depth osteochondral defects were created in the load-bearing medial femoral condyle of 20 mature goats and randomized into two groups. In group A (n = 6), a blood clot spontaneously filled the defect; in group B (n = 14), a single Ar-HA implant reconstructed the defect. The animals were sacrificed after either 6 or 12 months. Parameters assessed included clinical evaluation, x-rays, micro-CT, ultrasound and histology at both time points, and specimen high-field magnetic resonance imaging with T2 mapping at the 12-month time point.

RESULTS

In most group A animals, the defects were not reconstructed (1/3 at 6 months, and 0/3 at 12 months). Defects in group B were mostly reconstructed (5/7 at 6 months and 6/7 at 12 months). Group A defects were either empty or contained fibrous repair tissue; while group B filling was compatible with hyaline cartilage and normal bone.

CONCLUSION

Ar-HA scaffolds implanted in critical osteochondral defects result in hyaline cartilage formation and subchondral bone regeneration. The results improved at the 12-month time point compared to the 6-month time point, indicating a continuous maturation process without deterioration of the repair tissue.

CLINICAL RELEVANCE

Osteochondral defects are common in humans; the results of the current study suggest that an acellular Ar-HA scaffold might induce cartilage and subchondral bone regeneration.