Accuracy of synovial fluid analysis compared to histology for the identification of calcium pyrophosphate crystals: an ancillary study of the OMERACT US Working Group - CPPD subgroup.

The aim of this study was to evaluate the accuracy of synovial fluid analysis in the identification of calcium pyrophosphate dihydrate crystals compared to microscopic analysis of joint tissues as the reference standard. This is an ancillary study of an international, multicentre cross-sectional study performed by the calcium pyrophosphate deposition disease (CPPD) subgroup of the OMERACT Ultrasound working group. Consecutive patients with knee osteoarthritis (OA) waiting for total knee replacement surgery were enrolled in the study from 2 participating centres in Mexico and Romania. During the surgical procedures, synovial fluid, menisci and hyaline cartilage were collected and analysed within 48 hours from surgery under transmitted light microscopy and compensated polarised light microscopy for the presence/absence of calcium pyrophosphate crystals. All slides were analysed by expert examiners on site, blinded to other findings. A dichotomic score (absence/ presence) was used for scoring both synovial fluid and tissues. Microscopic analysis of knee tissues was considered the gold standard. Sensitivity, specificity, accuracy, positive and negative predictive values of synovial fluid analysis in the identification of calcium pyrophosphate crystals were calculated. 15 patients (53% female, mean age 68 yo ± 8.4) with OA of grade 3 or 4 according to Kellgren-Lawrence scoring were enrolled. 12 patients (80%) were positive for calcium pyrophosphate crystals at the synovial fluid analysis and 14 (93%) at the tissue microscopic analysis. The overall diagnostic accuracy of synovial fluid analysis compared with histology for CPPD was 87%, with a sensitivity of 86% and a specificity of 100%, the positive predictive value was 100% and the negative predictive value was 33%. In conclusion synovial fluid analysis proved to be an accurate test for the identification of calcium pyrophosphate dihydrate crystals in patients with advanced OA.

The role of PET in a clinically silent and ultrasound negative synovitis in the course of rheumatoid arthritis - a case report.

We present a case report of a rheumatoid arthritis patient, who underwent a PET scan, which revealed inflammation of multiple joints, which was missed by both physical and ultrasound examinations. A 55-year old woman with a long-term rheumatoid arthritis, who had undergone arthroplasty of the left knee in the past, consulted with the rheumatologist for pain in the left knee. The physical examination revealed signs of inflammation in the left knee and right elbow. The inflammatory parameters were high. Ultrasound showed intraarticular effusion without signs of active synovitis in the left knee. The ultrasound assessment of the other joints (hands, wrists and feet) was also negative for active synovitis, while positron-emission tomography (PET) revealed increased glucose metabolism at the level of the medial side of the left knee, left radio-ulno-carpal joint, I-II-III metacarpo-phalangeal joints bilaterally, right II metatarso-phalangeal joint, and left II-III metatarso-phalangeal joints. This case report demonstrates that PET might be more sensitive than ultrasound in detecting subclinical joint inflammation.

Nail ultrasonography for psoriatic arthritis and psoriasis patients: a systematic literature review.

To systematically review the role of ultrasound (US) in the assessment of the joint-enthesial-nail apparatus in patients with psoriatic arthritis (PsA) or psoriasis (PSO) in terms of prevalence, diagnosis, prognosis, monitoring and treatment. A systematic literature review was conducted through medical databases (PubMed, Embase) and the grey literature up to February 2018. The main areas of application of nail US were first identified, allowing the development of research questions, which were rephrased following the PICOs methodology to develop inclusion criteria. Of the 585 studies produced by PubMed and Embase searches, 17 studies met the criteria for inclusion. Five additional studies were included: 1 from the hand search and 4 from the 2016-2017 ACR and EULAR congresses. The prevalence of nail plate changes varied from < 10 to 97%, for power Doppler signal from 20-30 to 96% and distal interphalangeal joint (DIJ) involvement from 8.9 to 100%. The performance of US nail/DIJ abnormalities in the diagnosis of PsA and PSO elementary lesions was analysed by five studies, with a wide heterogeneity. Reproducibility and reliability of US nil/DIJ were assessed by interclass correlation coefficient or Cohen's k and their values ranged from 0.6 to 0.9. The value of US nail/DIJ in the monitoring of the lesions was analysed only by a single study. The analysis revealed applications for US nail/DIJ in PsA and PSO and highlights limitations. Validation is strongly needed to demonstrate its appropriateness in the clinical practice and to define its diagnostic and prognostic role.

Amendment of the OMERACT ultrasound definitions of joints' features in healthy children when using the DOPPLER technique.

BACKGROUND: Recently preliminary ultrasonography (US) definitions, in B mode, for normal components of pediatric joints have been developed by the OMERACT US group. The aim of the current study was to include Doppler findings in the evaluation and definition of normal joint features that can be visualized in healthy children at different age groups. METHODS: A multistep approach was used. Firstly, new additional definitions of joint components were proposed during an expert meeting. In the second step, these definitions, along with the preliminary B-mode-US definitions, were tested for feasibility in an exercise in healthy children at different age groups. In the last step, a larger panel of US experts were invited to join a web-based consensus process in order to approve the developed definitions using the Delphi methodology. A Likert scale of 1-5 was used to assess agreement. RESULTS: Physiological vascularity and fat pad tissue were identified and tested as two additional joint components in healthy children. Since physiological vascularity changes over the time in the growing skeleton, the final definition of Doppler findings comprised separate statements instead of a single full definition. A total of seven statements was developed and included in a written Delphi questionnaire to define and validate the new components. The final definitions for fat pad and physiological vascularity agreed by the group of experts reached 92.9% and 100% agreement respectively in a web survey. CONCLUSION: The inclusion of these two additional joints components which are linked to detection of Doppler signal in pediatric healthy joints will improve the identification of abnormalities in children with joint pathologies.

Ultrasound in the diagnosis of calcium pyrophosphate dihydrate deposition disease. A systematic literature review and a meta-analysis.

OBJECTIVE: Ultrasonography (US) demonstrated to be a promising tool for the diagnosis of calcium pyrophosphate dihydrate deposition disease (CPPD). The aim of this systematic literature review (SLR) was to collect the definitions for the US elementary lesions and to summarize the available data about US diagnostic accuracy in CPPD. METHODS: We systematically reviewed all the studies that considered US as the index test for CPPD diagnosis without restrictions about the reference test or that provided definitions about US identification of CPPD. Sensitivity and specificity were calculated for each study and definitions were extrapolated. Subgroup analyses were planned by anatomical site included in the index text and different reference standards. RESULTS: Thirty-seven studies were included in this review. All the studies were eligible for the collection of US findings and all definitions were summarized. US description of elementary lesions appeared heterogeneous among the studies. Regarding US accuracy, 13 articles entered in the meta-analysis. Considering each joint structure, the sensitivity ranged between 0.77 (0.63-0.87) and 0.34 (0.16-0.58) while the specificity varies between 1.00 (0.89-1.00) and 0.92 (0.16-1.00). Considering the reference standards used, the sensibility ranged between 0.34 (0.02-0.65) and 0.87 (0.76-0.99) while specificity ranged between 0.84 (0.52-1.00) and 1.00 (0.99-1.00). CONCLUSION: US is potentially a useful tool for the diagnosis of CPPD but universally accepted definitions and further testing are necessary in order to assess the role of the technique in the diagnostic process.

Global ultrasound assessment of structural lesions in osteoarthritis: a reliability study by the OMERACT ultrasonography group on scoring cartilage and osteophytes in finger joints.

OBJECTIVE: Ultrasonography is sensitive for the evaluation of cartilage pathology and degree of osteophytes in patients with hand osteoarthritis (OA). High consistency of assessments is essential, and the OMERACT (Outcome Measures in Rheumatology) ultrasonography group took the initiative to explore the reliability of a global ultrasonography score in patients with hand OA using semiquantitative ultrasonography score of cartilage and osteophytes in finger joints. METHODS: Ten patients with hand OA were examined by 10 experienced sonographers over the course of two days. Semiquantitative scoring (0-3) was performed on osteophytes (carpo-metacarpal 1, metacarpo-phalangeal (MCP) 1-5, proximal interphalangeal 1-5 and distal interphalangeal 2-5 joints bilaterally with an ultrasonography atlas as reference) and cartilage pathology (MCP 2-5 bilaterally). A web-based exercise on static cartilage images was performed a month later. Reliability was assessed by use of weighted κ analyses. RESULTS: Osteophyte scores were evenly distributed, and the intraobserver and interobserver reliabilities were substantial to excellent (κ range 0.68-0.89 and mean κ 0.65 (day 1) and 0.67 (day 2), respectively). Cartilage scores were unevenly distributed, and the intraobserver and interobserver reliability was fair to moderate (κ range 0.46-0.66 and mean κ 0.39 (day 1) and 0.33 (day 2), respectively). The web-based exercise showed acceptable agreement for cartilage being normal (κ 0.47) or with complete loss (κ 0.68), but poor for the intermediate scores (κ 0.22-0.30). CONCLUSIONS: Use of the present semiquantitative ultrasonography scoring system for cartilage pathology in hand OA is not recommended (while normal or total loss of cartilage may be assessed). However, the OMERACT ultrasonography group will endorse the use of semiquantitative scoring of osteophytes with the ultrasonography atlas as reference.

Atlas-based knee osteophyte assessment with ultrasonography and radiography: relationship to arthroscopic degeneration of articular cartilage.

OBJECTIVES: To investigate intra- and inter-reader agreement of ultrasonography (US) and conventional radiography (CR) for the evaluation of osteophyte presence and size within the tibiofemoral joint. In addition, to correlate these findings with arthroscopic degeneration of the articular cartilage. METHOD: Forty adult patients with knee pain were enrolled in this study. Knee CR and US scanning of the medial and lateral bone margins were performed on all patients. A novel atlas for the US grading of knee osteophytes was used in the evaluation. The number and size of the osteophytes were evaluated semi-quantitatively in two rounds from both the CR images (four readers) and the US images (14 readers). The Noyes grading system was used for the evaluation of arthroscopic degeneration of the articular cartilage in 26 patients. RESULTS: On average, intra- and inter-reader US and CR agreement was substantial and comparable to each other (κ = 0.60-0.72). US detected more osteophytes than CR at both the medial (65% vs. 48%) and lateral (70% vs. 60%) compartments. A statistically significant correlation between CR- or US-based osteophyte and arthroscopy grades was observed only for US at the medial compartment (rs = 0.747, p < 0.001). CONCLUSIONS: The detection of knee osteophytes using the novel US atlas is as reproducible as reading conventional radiographs. US is more sensitive to detect knee osteophytes than CR. Furthermore, osteophytes detected with US correlate significantly with arthroscopic cartilage changes at the medial knee compartment whereas those detected by CR do not.

Educational recommendations for the conduct, content and format of EULAR musculoskeletal ultrasound Teaching the Teachers Courses.

OBJECTIVE: To produce educational guidelines for the conduct, content and format of theoretical and practical teaching at EULAR musculoskeletal ultrasound (MSUS) Teaching the Teachers (TTT) Courses. METHODS: A Delphi-based procedure with 24 recommendations covering five main areas (Duration and place of the course; Faculty members; Content of the course; Evaluation of the teaching skills; TTT competency assessment) was distributed among a group of experts involved in MSUS teaching, in addition to an advisory educational expert being present. Consensus for each recommendation was considered achieved when the percentage of agreement was >75%. RESULTS: 21 of 24 invited participants responded to the first Delphi questionnaire (88% response rate). All 21 participants also responded to the second round. Agreement on 19 statements was obtained after two rounds. CONCLUSIONS: This project has led to the development of guidelines for the conduct, content and format of teaching at the EULAR MSUS TTT Courses that are organised annually, with the aim of training future teachers of EULAR MSUS Courses, EULAR Endorsed MSUS Courses, as well as national and local MSUS Courses. The presented work gives indications on how to homogenise the teaching at the MSUS TTT Courses, thus resolving current discrepancies in the field.

Radiologists and rheumatologists on performing and reporting shoulder ultrasound: from disagreement to consensus.

Shoulder pain is a common condition in the rheumatologist's practice, yet there are no guidelines on how to report shoulder ultrasound (US) examinations. The aim of this study was to compare scanning and reporting techniques performed by radiologists and rheumatologists and identify any discrepancies between the two. The participants in this study were five rheumatologists and two radiologists specialized in musculoskeletal US. The study was divided in 2 phases. In the first phase, each participant performed an US of 3 patients and reported the findings without knowing the patient diagnosis and the findings reported by the other operators. Other three investigators reported the US technique of each operator. Reports and images were subsequently compared to identify any discrepancies and reach consensus on a common approach. In the second phase, a US scan was performed on a fourth patient in a plenary session to assess feasibility and efficacy of the common approach The US scanning technique was similar for all operators. The differences in reporting emerged in the description of the rotator cuff disease. Radiologists provided a detailed description of lesions (measurements along 2 axis and scoring of lesions), whereas rheumatologists described carefully the inflammatory changes. The experts concluded that lesions should be measured along 2 axes and the grade of degeneration and the age of the lesion should be reported. Another difference emerged in the description of the irregularities of the bone surface. The experts concluded that the term erosion should be used only when an inflammatory joint disease is suspected. This study led to the clarification of some inconsistencies in US reporting, and represented an interesting collaborative experience between radiologists and rheumatologists.

Defining enthesitis in spondyloarthritis by ultrasound: results of a Delphi process and of a reliability reading exercise.

OBJECTIVE: To standardize ultrasound (US) in enthesitis. METHODS: An initial Delphi exercise was undertaken to define US-detected enthesitis and its core components. These definitions were subsequently tested on static images taken from spondyloarthritis patients in order to evaluate their reliability. RESULTS: Excellent agreement (>80%) was obtained for including hypoechogenicity, increased thickness of the tendon insertion, calcifications, enthesophytes, erosions, and Doppler activity as core elementary lesions of US-detected enthesitis. US definitions were subsequently obtained for each elementary component. On static images, the intraobserver reliability showed a high degree of variability for the detection of elementary lesions, with kappa coefficients ranging from 0.13-1. The interobserver kappa values were variable, with the lowest kappa coefficient for enthesophytes (0.24) and the highest coefficient for Doppler activity at the enthesis (0.63). CONCLUSION: This is the first consensus-based US definition of enthesitis and its elementary components and the first step performed to ensure a higher degree of homogeneity and comparability of results between studies and in daily clinical work.

Ultrasound elastography is a reproducible and feasible tool for the evaluation of the patellar tendon in healthy subjects.

OBJECTIVE: To evaluate the feasibility and reproducibility of ultrasound elastography (UE) in the assessment of healthy patellar tendon and to describe its UE pattern. METHODS: Twenty-two patellar tendons of 11 out of 16 healthy subjects who met the inclusion criteria were evaluated three times by ultrasound (US) and UE at their proximal, middle and distal portions, by two separate sonographers with different experiences in UE. RESULTS: In all tendon portions the color map analysis showed a predominance of green (highly elastic), with good values of intra-observer (Operator 1: P-values = 0.790, 0.864, 0.865; Operator 2: P = 0.642, 0.882, 0.613 for proximal, middle and distal portions, respectively) and inter-observer (P = 0.657) agreement. For both operators the intra-observer analysis of the elasticity ratio (ER) between the tendon and the subcutis showed high agreement values (P < 0.001 for both operators). The inter-observer analysis showed also high agreement values (P < 0.001 at proximal, P = 0.001 at middle, P = 0.005 at distal portions). The overall analysis of the ER of the tendon portions showed values of (mean ± SD): 1.47 ± 0.64, 4.38 ± 1.36, 3.32 ± 1.20 for proximal, middle and distal portions, respectively. The mean time to perform the UE evaluation for the inexperienced operator was 5 min at the beginning of the study but decreased to 2 min after a few examinations were done. The mean time for the expert was 2 min for the entire study. CONCLUSIONS: UE is a feasible and reproducible tool for the evaluation of the healthy patellar tendon and further data are needed to define its role in the assessment of tendon pathology.

EFSUMB minimum training requirements for rheumatologists performing musculoskeletal ultrasound.

In order to optimize and standardize musculoskeletal ultrasonography education for rheumatologists, there is a need for competency assessments addressing the required training and practical and theoretical skills. This paper describes how these competency assessments for rheumatologists were developed and what they contain.

Diffusion and applications of musculoskeletal ultrasound in Italian Rheumatology Units.

The Musculoskeletal Ultrasound Study Group of the Italian Society of Rheumatology (SIR) was founded during the 68th SIR Congress, on November 2011. The request of activation of this group was based on the increasing interest and the widespread diffusion of ultrasound in the scientific rheumatology community and on the solid experience of some Italian rheumatologists in the field. The aims of the Study Group are to stimulate the applications and use of ultrasound in the clinical practice at the level of the Italian rheumatology units and, in addition, to develop research projects at a national level...

The reliability of musculoskeletal ultrasound in the detection of cartilage abnormalities at the metacarpo-phalangeal joints.

OBJECTIVE: To assess the reliability of ultrasound (US) in detecting cartilage abnormalities at the metacarpo-phalangeal (MCP) joints in people with cartilage pathology. METHODS: Nine expert ultrasonographers initially achieved consensus on definitions and scanning protocols. They then examined the second to fifth MCP joints of the dominant hand of eight people with hand osteoarthritis (OA). US examinations were conducted in two rounds, with independent blinded evaluations of cartilage lesions. Global cartilage abnormalities were assessed by applying a dichotomous (presence/absence) score; in addition, the following lesions were evaluated using the same scoring system: loss of anechoic structure and/or thinning of the cartilage layer, and irregularities and/or loss of sharpness of at least one cartilage margin. Reliability was assessed using kappa (k) coefficients. RESULTS: Thirty-two joints were examined. Intra-observer k values ranged from 0.52 to 1 for global cartilage abnormalities; k values ranged from 0.54 to 0.94 for loss of anechoic structure and/or thinning of cartilage layer and from 0.59 to 1 for irregularities and/or loss of sharpness of at least one cartilage margin. Values of k for inter-observer reliability were 0.80 for global cartilage abnormalities, 0.62 for loss of anechoic structure and/or thinning of cartilage layer, and 0.39 for irregularities and/or loss of sharpness of at least one cartilage margin. CONCLUSION: US is a reliable imaging modality for the detection of cartilage abnormalities in patients with cartilage pathology in the MCP joints. The analysis of specific cartilage measures showed more variable results that may be improved by modifying definitions and further standardization of US techniques.

Ultrasound imaging for the rheumatologist XXXIX. Sonographic assessment of the hip in fibromyalgia patients.

Fibromyalgia syndrome (FMS) is a common form of non-inflammatory rheumatism within the general population with symptoms often mimicking those of arthritis or muscle disorders. Arthralgic symptoms in the region of the hip are commonly mentioned by patients with FMS and one of the diagnostic trigger points for the condition is found around the greater trochanter. To date, no formal imaging studies using ultrasound (US) have been performed in FMS. This study describes the correlation between clinical and US findings in patients presenting with primary FMS to rheumatology clinics. In the majority of the patients, no significant pathological US abnormalities were detected.

Role of scintigraphy with 99mTc-infliximab in predicting the response of intraarticular infliximab treatment in patients with refractory monoarthritis.

PURPOSE: The rationale for the present study was to evaluate the predictive role of (99m)Tc-infliximab scintigraphy in therapy decision-making in patients with refractory monoarthritis and also candidates for intraarticular (IA) infliximab treatment. METHODS: We studied 12 patients (5 with rheumatoid arthritis and 7 with spondyloarthropathy) with active monoarthritis (11 knees and 1 ankle) that had lasted for at least 3 months. Patients were evaluated clinically and ultrasonographically at baseline and 12 weeks after IA administration of infliximab. At the same time-points, (99m)Tc-infliximab scintigraphy was performed: planar anterior and posterior images of arthritic joints were acquired at 6 and 20 h after injection and target-to-background (T/B) ratios were calculated. RESULTS: After treatment, a significant improvement in clinical and ultrasonographic parameters was recorded in six patients. Three patients had a partial response and three did not respond. Regarding scintigraphic evaluation, the T/B ratio analysis showed a significantly higher uptake in affected than in nonaffected joints before therapy (1.78 ± 0.46 vs. 1.29 ± 0.27, p = 0.006 at 6 h; 2.05 ± 0.50 vs. 1.41 ± 0.36 at 20 h, p = 0.002), and mean uptake at 20 h was also significantly higher than at 6 h (p = 0.0004). Scintigraphy showed a significant decrease in posttherapy T/B ratios of the affected joints (p = 0.0001 at 6 h and p = 0.0001 at 20 h), indicating a reduction in TNF into the affected joints. Most importantly, responders showed a significantly higher percentage increase in pretherapy uptake from 6 h to 20 h in the affected joints than nonresponders (p = 0.00001). CONCLUSION: The results of the present investigation suggest that (99m)Tc-infliximab scintigraphy could be a useful tool to predict the clinical response to IA infliximab treatment in patients with refractory monoarthritis.

Ultrasound imaging for the rheumatologist XXXVII. Sonographic assessment of the hip in ankylosing spondylitis patients.

OBJECTIVES: To investigate the prevalence of ultrasound (US) detectable inflammation in hips of patients with ankylosing spondylitis (AS) and the relationship between US and measures of disease activity and severity. METHODS: Consecutive patients with AS attending the rheumatology units involved in this study were enrolled. Clinical and demographical data were recorded. US examination of bilateral hips was performed at the same time, evaluating anterior longitudinal scan to search for synovial hypertrophy (SH), joint effusion (JE) or power Doppler (PD) positive synovitis. RESULTS: A total of 56 patients were included, median age (interquartile range, IQR) 49 (39, 59.5), median disease duration 98 (72, 204) months, 80.3% were treated with TNF-α inhibitors, median BASDAI 2.65 (1.96, 3.95), 30.3% had hip tenderness. US JE was found in 26.7% of patients, US SH in 16%, no patient had detectable PD. The concordance between clinical findings and US abnormalities was moderate, with a kappa of 0.44. Patients with detectable US abnormalities had higher median visual analogue scale (VAS) pain and C-reactive protein (CRP), while there was no significant association with other measures of disease activity and disability. In the subgroup of patients with no hip tenderness, US alterations were still significantly related to higher CRP levels, while in patients with hip tenderness and no US abnormalities CRP was not higher than in the asymptomatic patients. CONCLUSIONS: US assessment of hip joint in AS patients can be considered of value, as suggested by the correlation with relevant clinical and laboratory measures. In asymptomatic patients, US examination might provide further information on subclinical involvement.

Ultrasound evaluation of fluid in knee recesses at varying degrees of flexion.

OBJECTIVE: Various methods are utilized in daily practice to obtain optimal information on effusion in the knee. Our aim is to investigate which scanning position provides the best information about synovial fluid in the knee by using ultrasound and to evaluate the magnitude of difference for measuring synovial fluid in 3 major recesses (suprapatellar, medial parapatellar, and lateral parapatellar) of the knee according to various degrees of flexion. METHODS: Sonographers in 14 European centers documented bilateral knee joint ultrasound examinations on a total of 148 knee joints. The largest sagittal diameter of fluid was measured in scans corresponding to the 3 major recesses at different (0°, 15°, 30°, 45°, 60°, and 90°) degrees of flexion of the knee. The difference of measurement of effusion according to transducer position, knee position, and the interaction between them was investigated by analysis of variance followed by Tukey's test. RESULTS: No correlation was noted between patient characteristics and ultrasound detection of effusion. The sagittal diameter of synovial fluid in all 3 recesses was greatest at 30° flexion. Analysis of variance and Tukey's test revealed that the suprapatellar scan and 30° flexion is the best combination for detecting effusion as confirmed by receiver operator characteristic curve analysis. CONCLUSION: The suprapatellar scan of the knee in 30° flexion was the most sensitive position to detect fluid in knee joints. Sagittal diameter of fluid in all 3 recesses increased with the knee in the 30° flexed position as compared to the extended position.

Which knee and probe position determines the final diagnosis of knee inflammation by ultrasound? Results from a European multicenter study.

PURPOSE: To investigate which knee and probe position best identifies knee inflammation and to determine a cut-off level for abnormal synovial effusion. MATERIALS AND METHODS: 18 experienced sonographers (all rheumatologists) performed ultrasound examinations of the knee joint in patients with knee symptoms and in healthy controls. Each sonographer performed longitudinal suprapatellar ultrasound scans using 9 different configurations at each knee: Midline, parapatallar lateral and parapatellar medial from midline in neutral position (0°) with and without quadriceps muscle contraction and in 30° flexion of the knee. The presence of synovial effusion (SE), the effusion measured in millimeters and the presence of synovial hypertrophy (SH) was noted. RESULTS: A total of 298 knees of 149 subjects (129 patients and 20 controls) were examined. The detection of SH is more sensitive and specific than the detection of SE, independently of the knee and probe position, for the final diagnosis of abnormality. The detection of both synovial hypertrophy and effusion in the knee in neutral position (0°) with quadriceps contraction and with the probe in the midline position, are the best independent predictors for knee abnormalities. Knee effusion > 3.2 mm measured with the probe in the lateral aspect of the knee is the best diagnostic characteristics for predicting pathological SE. CONCLUSION: The best combination for detecting SH and SE is obtained by placing the probe in the midline position with the knee in 0° with quadriceps contraction. A cut-off value for pathological effusion may be obtained in the lateral aspect of the knee.