Arthroscopic evaluation of the synovial lining before and after open synovectomy of the knee joint in patients with chronic inflammatory joint diseases

Twenty-eight patients with chronic inflammatory joint diseases had arthroscopy immediately before synovectomy of the knee joint and 6 and 12 months postoperatively. In patients with moderate and/or severe synovitis of the knee joint all of the synovial membrane is involved in the disease process. Resynovitis (synovitis of the regenerated synovial membrane after synovectomy), however, is patchy and if biopsy should be indicated, arthroscopic guidance is advocated. Following synovectomy there is a recurrence of mild synovitis of varying degree in some cases with an increase in resynovitis between 6 and 12 months. The level of synovitis at 12 months was, however, markedly less than at synovectomy (p less than 0.01). Similar development was found both in histopathology and immunohistopathology after synovectomy. Arthroscopic examination of the synovial membrane in chronic inflammatory disease of the knee joints gives valuable information of the severity and the longitudinal changes of synovitis. A simple method of scoring is described and is imperative when comparing patients or groups of patients and when doing longitudinal arthroscopic studies. The method was used both at arthroscopy and at subsequent synovectomy giving a highly significant correlation (p less than 0.001).     

Vascular changes in psoriatic knee joint synovitis.

OBJECTIVE: To evaluate the diagnostic utility of standard arthroscopy supported by a computerized image analysis system; and to examine and quantify the macroscopic appearance of blood vessels in selected anatomical areas, comparing 2 groups of patients with PsA and RA with refractory knee joint synovitis (KJS) for vascular marking (VM) features and VM scores, as well as for the relationship between respective VM scores and local and systemic KJS disease activity indices. METHODS: Standard arthroscopy was carried out on 39 knees (20 PsA, 19 RA). Videorecordings of the examination were reanalyzed using a computer image analysis system and software. The appearance of vascular markings was assessed and separately scored for the areas of surface synovium (capsular, CVM), villous proliferation (villous, VVM), and synovium adherent to cartilage (pannus, PVM). Indices of systemic (erythrocyte sedimentation rate, ESR) and local KJS disease activity (clinical index) were obtained before arthroscopy. The morphology and scores of the distinct VM were compared between PsA and RA groups, as was the relationship between respective VM scores and ESR and KJS clinical indices. RESULTS: Distinctive VM features were observed for PsA and RA KJS in each separate synovial architecture examined. VVM and CVM scores were significantly correlated with each other in PsA knees, and were significantly higher in PsA compared with RA. In both diseases, VVM and CVM scores were not related to KJS duration or activity or to ESR values, but in RA they were directly correlated with KJS activity. Moreover, the VVM capillary feature "meandering with tight convolutions," considered unique to psoriatic skin, was observed in the synovium of 13 PsA (65%) and one RA KJS (5.5%). The mean KJS duration of the PsA group with typical VVM was significantly lower than the group without VVM (2.6 +/- 1.77 vs 9.4 +/- 8.28 yrs). CONCLUSION: Our macroscopic observations of distinct changes in VM expression in selected anatomical areas of PsA and RA KJS suggest possible pathogenetic differences between the 2 diseases. The typical morphology and higher intensity of villous vascularization, in both early and chronic disease, and the different clinical relevance of VVM scores in PsA compared with RA KJS support the potential use of vascular markings as reliable outcome measures of the PsA process in KJS.     

A comparison of clinical vs ultrasound determined synovitis in rheumatoid arthritis utilizing gray-scale, power Doppler and the intravenous microbubble contrast agent 'Sono-Vue'

OBJECTIVES: Synovitis in rheumatoid arthritis (RA) is assessed clinically by the presence of joint tenderness and swelling. Synovial thickening and increased vascularity may also be detected by high-resolution ultrasonography (US) and power Doppler (PD). This study investigated the relationship between clinical and sonographic features of synovial disease utilizing US, PD and the contrast agent Sono-Vue. METHODS: Forty RA patients were recruited. One proximal inter-phalangeal or metacarpophalangeal joint was selected per patient, as being unambiguously either: swollen and tender, just swollen, just tender or neither swollen nor tender (Nil). Ten joints were selected per clinical group. On US, the mean synovial thickness was measured and synovial hypertrophy and erosions were graded subjectively. Synovial vascularity demonstrated by PD was scored subjectively pre- and post-contrast. RESULTS: All grades of synovial vascularity were found in each clinical group including the Nil group. There were significant differences between the four clinical groups for both synovial hypertrophy (P = 0.024) and PD scores pre- (P = 0.022) and post- (P = 0.039) contrast. Tender-only joints showed significantly less vascularity than other groups. Post-contrast, the median PD scores increased in all but the Nil group, in some cases from the normal to abnormal range. CONCLUSION: Synovitis demonstrated by US and PD is not predicted by patterns of disease as described by joint swelling and tenderness despite unambiguous selection of joints. Synovial vascularity was the least in tender-only joints and was heterogeneous in all other groups, including Nil joints. These findings question the reliability of traditional clinical signs in RA synovitis assessment.     

Synovial inflammation in patients with early osteoarthritis of the knee

While synovitis is common in advanced osteoarthritis (OA), its prevalence and severity in patients with early or mild OA are uncertain. In our study synovial biopsies from patients with arthroscopic evidence of OA whose radiographs were normal, or showed only mild/moderate changes of OA, were examined to determine the prevalence and severity of lining cell proliferation and mononuclear cell infiltration. Synovitis was present in only 16 of 29 patients (55%) who underwent arthroscopy because of chronic knee pain and were found to have OA; no synovium from 50% of the 22 patients in this group with full thickness cartilage ulceration showed infiltration with mononuclear cells. Similarly, no evidence of synovitis was seen in biopsies from 7 of 14 additional patients with OA who did not have knee pain but who underwent arthroscopy to evaluate joint instability. An association was seen between synovial mononuclear cell infiltration and thickness of the synovial lining cell layer (p less than 0.03), but lining cell hyperplasia was found in samples from only 12% of the patients with OA in our series. The severity of OA cartilage lesions was unrelated to severity of synovitis and no topographic relationship was found between cartilage ulceration and synovitis.     

Power Doppler sonography in the evaluation and follow-up of knee involvement in patients with juvenile idiopathic arthritis

INTRODUCTION: This study was undertaken to evaluate the role of ultrasound (US), conventional color (CD) and power Doppler (PD) in the detection and quantification of inflammatory signs of the knee in children with juvenile idiopathic arthritis (JIA) and to correlate these findings with patient history, clinical, laboratory and radiological findings. PATIENTS AND METHODS: Thirty patients with JIA who had clinical signs of knee involvement as well as 15 healthy children as a control group where subjected to full clinical examination and laboratory investigations on the same day of US examination. The knee joints were evaluated with plain radiography, US, and color Doppler in 13 patients, while the remaining 17 were assessed with power Doppler. Fourteen patients were subjected to follow-up assessment. RESULTS: A highly significant difference in synovial thickening and cartilage thickness detected by US between JIA affected knees and those of controls (p < 0.0001). Knee effusion was demonstrated in 93% of patients. Synovial vessels were detected by Doppler in 76.7% of patients. A significant correlation was detected between the degree of vascularity detected by PD and knee score (p < 0.05), and JAFAR score (P < 0.05). On comparing the findings of the follow-up with those of the initial examination, a significant positive correlation was detected between the differences in the knee score and those in synovial thickness (p < 0.05), and with the vascularity scale detected by PD (p < 0.05). CONCLUSION: This study suggests the Doppler sonography as a non-invasive, low-cost, and readily available tool for the evaluation and follow-up of articular involvement in knees of JIA patients.     

Inflammatory low back pain: high negative predictive value of contrast-enhanced color Doppler ultrasound in the detection of inflamed sacroiliac joints

OBJECTIVE: To determine the value of microbubble contrast agents for color Doppler ultrasound (CDUS) compared with magnetic resonance imaging (MRI) in the detection of active sacroiliitis. METHODS: An observational case-control study of 103 consecutive patients (206 sacroiliac [SI] joints) with inflammatory low back pain according to the Calin criteria and 30 controls (60 SI joints) without low back pain was conducted at the University Hospital of Innsbruck. All patients and controls underwent unenhanced and contrast-enhanced CDUS and MRI of the SI joints. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of unenhanced and contrast-enhanced CDUS were evaluated. RESULTS: Forty-three patients (41%) with 70 of 206 SI joints (34%) and none of the controls nor the 60 control SI joints demonstrated active sacroiliitis on MRI. Unenhanced CDUS showed a sensitivity of 17%, a specificity of 96%, a PPV of 65%, and an NPV of 72%; contrast-enhanced CDUS showed a sensitivity of 94%, a specificity of 86%, a PPV of 78%, and an NPV of 97%. Detection of vascularity in the SI joint was increased by contrast administration (P < 0.0001). Clustered receiver operating curve analysis demonstrated that enhanced CDUS (A(z) = 0.89) was significantly better than unenhanced CDUS (A(z) = 0.61) for the diagnosis of active sacroiliitis verified by MRI (P < 0.0001; 2-sided test). CONCLUSION: Microbubble contrast-enhanced CDUS is a sensitive technique with a high NPV for detection of active sacroiliitis compared with MRI.     

Phase inversion harmonic imaging versus contrast-enhanced power Doppler sonography for the characterization of focal liver lesions

BACKGROUND AND AIMS: We compared contrast-enhanced power Doppler sonography (CEPD) and phase-inversion harmonic imaging (PIHI) in the assessment of liver lesion vascularity and characterization of focal liver lesions. MATERIALS AND METHODS: We examined 101 focal liver lesions by CEPD and PIHI using Optison as echo-enhancing agent. Amount and architecture of lesion vascularity and the kinetics of contrast enhancement in the lesions were analyzed. A tumor diagnosis was assessed after each examination. RESULTS: Analysis of tumor vascularity was not possible in 30 liver lesions (30%) due to motion or blooming artifacts by CEPD. Vascularity was detected in 61% of liver lesions by CEPD and in 95% by PIHI. PIHI identified significantly more tumor vascularity pattern (93%) than CEPD (57%). Specific lesion diagnosis based on PIHI led to correct results in 92% compared to 59% by CEPD. CONCLUSION: PIHI is highly efficient in detecting tumor vascularity and is superior to CEPD in characterizing focal liver lesions.     

Prolidase expression in knee osteoarthritis and healthy controls: Observational study

Prolidase enzyme activity is important for collagen resynthesis. In late stages of osteoarthritis (OA) its activity is decreased.To evaluate prolidase expression in knees of patients undergoing total arthroplasty for OA, and compare with young people undergoing knee arthroscopy due to traumatic injuries.In this cross-sectional study we included 20 patients with OA grade IV who underwent total knee arthroplasty and 20 controls of young patients who underwent arthroscopy for another reason besides OA. All participants were evaluated by knee ultrasound before the procedure. During the procedure, synovial tissue biopsies were taken and analyzed by immunofluorescence to search inflammation. Measures of central tendency, dispersion measures and position measures were used for the case of quantitative variables. Student t test or Mann–Whitney U test, and the logistic regression of Cox, was used.Prolidase expression in the synovial biopsy was significantly lower in the OA group than in the controls (0.017 ± 0.009 vs 0.062 ± 0.094, P < .05). Power Doppler (PD) signal was present in the synovitis of all knee recesses of the OA group in grayscale and in 17 (85%) of knees. The mean of the micro-vessel count in patients with OA was significantly higher vs controls (11 + 5.3 vs 4 + 2.1, P = .001). The neovascularization correlated significantly with the presence of PD signal in patients with OA (1.16, 95% CI, 1.02–1.34, P = .02).The prolidase expression in the synovial membrane evaluated by immunofluorescence, in patients with late stages of knee OA, is low, which may be interpreted as an evidence of decreased collagen resynthesis.     

Synovitis occurs in some clinically normal and asymptomatic joints in patients with early arthritis

OBJECTIVE: To determine if clinically asymptomatic knee joints in patients with recent onset arthritis reveal histological evidence of synovitis. METHODS: As part of a prospective study of patients with synovitis of less than one year duration, we performed blind needle biopsies on the knees of 20 patients who had synovitis elsewhere but no symptoms or detectable swelling or tenderness of the biopsied joint. RESULTS: Histologic evidence of synovitis was observed in 11 knees (55%). All patients with synovitis had evidence of synovial lining cell hyperplasia, increased vascularity, and lymphocytic infiltrates. Five of 6 patients with rheumatoid arthritis (RA) and 5 of 8 with undifferentiated arthritis had histological evidence of synovitis, but none of the 5 with reactive arthritis (ReA) had synovitis in the asymptomatic joints. Histologic evidence of synovitis persisted in some after clinical resolution of previous pain and swelling, while it occurred in others with no history of previous involvement of that knee. CONCLUSION: Even asymptomatic joints in patients with RA and undifferentiated arthritis of recent onset reveal histologic signs of synovitis. The earliest changes may occur before symptoms. Histologic changes also persist after resolution of previous early symptoms. Evidence of inflammation was not present in asymptomatic joints in our 5 patients diagnosed with ReA.     

Quantitative magnetic resonance imaging as marker of synovial membrane regeneration and recurrence of synovitis after arthroscopic knee joint synovectomy: a one year follow up study

OBJECTIVES: By repeated magnetic resonance imaging (MRI) to study synovial membrane regeneration and recurrence of synovitis after arthroscopic knee joint synovectomy in patients with rheumatoid arthritis (RA) and other (non-RA) causes of persistent knee joint synovitis. METHODS: Contrast enhanced MRI was performed in 15 knees (nine RA, six non-RA) before and one day, seven days, two months, and 12 months after arthroscopic synovectomy. Synovial membrane volumes, joint effusion volumes, and cartilage and bone destruction were assessed on each MRI set. Baseline microscopic and macroscopic assessments of synovitis and baseline and follow up standard clinical and biochemical examinations were available. RESULTS: Synovial membrane and joint fluid volumes were significantly reduced two and 12 months after synovectomy. However, MRI signs of recurrent synovitis were already present in most knees at two months. No significant differences between volumes in RA and non-RA knees were seen. Synovial membrane volumes at two months were significantly inversely correlated with the duration of clinical remission, for all knees considered together (Spearman's correlation r(s)=-0.67; p<0.05), for RA knees (r(s)=-0.76; p<0.05), and for non-RA knees (r(s)=-0.83; p<0.05). Baseline volumes were not significantly correlated with clinical outcome. Only three knees (all RA) showed erosive progression. The rate of erosive progression was not correlated with MRI volumes or with clinical or biochemical parameters. CONCLUSION: The synovial membrane had regenerated two months after arthroscopic knee joint synovectomy and despite significant volume reductions compared with baseline it often showed signs of recurrent synovitis. MRI seems to be valuable as a marker of inflammation, destruction and, perhaps, as a predictor of therapeutic outcome in arthritis.     

Needle Arthroscopy of the Knee with Synovial Biopsy Sampling: Technical Experience in 150 Patients

Needle arthroscopy is an office-based technique allowing direct visualisation of the knee cavity and selective sampling of the synovial membrane. We performed needle arthroscopy in 150 patients with synovitis of the knee (1) to evaluate the diagnostic potential in early arthritis, (2) to perform therapeutic lavage in persistent inflammatory synovitis and (3) to assess the balance between technical feasibility, safety and patient comfort on the one hand, and the relevance of the obtained macro- and microscopic information for diagnosis and research purposes on the other. After disinfection of the leg and local anaesthesia of the skin and joint, a 1.8–2.7 mm needle arthroscope was introduced into the knee. Synovial fluid was aspirated and lavage of the joint cavity was performed to allow macroscopic evaluation of hyperaemia and hypertrophy of the synovial membrane. Biopsies were taken at inflamed sites, followed by another lavage to remove blood and debris. Needle arthroscopy of the knee is a simple and easy to perform technique made particularly attractive by the local anaesthesia and the ambulatory setting. It allows good macroscopic evaluation of synovial inflammation and selective sampling of the synovial membrane. Biopsies are suitable for RNA and DNA extraction, bacterial or lymphocyte culture, and cell isolation. Because samples were sometimes too small for representative histology, we switched from a 1.8 mm to a 2.7 mm biopsy forceps with good results. In nearly all cases the arthroscopy was well tolerated. Moreover, some patients reported relief of symptoms and even improvement of mobility after lavage of the inflamed joint. No major complications were noted. It was concluded that needle arthroscopy of the knee is a simple, safe and well-tolerated technique, with promising perspectives as a diagnostic, scientific and possibly therapeutic tool in rheumatic diseases. Received: 4 January 1999 / Accepted: 21 March 1999     

Assessment of inflammatory activity in rheumatoid arthritis: a comparative study of clinical evaluation with grey scale and power Doppler ultrasonography

OBJECTIVE: To compare the clinical assessment of overall inflammatory activity in patients with rheumatoid arthritis (RA) with grey scale and power Doppler (PD) ultrasonography (US). METHODS: Ninety four consecutive patients with RA were included. Demographic and clinical data, C reactive protein (CRP) level, and erythrocyte sedimentation rate (ESR) were recorded for each patient. The presence of tenderness, swelling, and a subjective swelling score from 1 to 3 were independently assessed by two rheumatologists, who reached a consensus in 60 joints examined in each patient. All patients underwent a US examination by a third blinded rheumatologist, using PD. US joint effusion, synovitis, and PD signal were graded from 1 to 3 in the 60 joints. Joint count and joint index for effusion, synovitis, and PD signal were recorded. A 28 joint count for clinical and US variables was calculated. Interobserver reliability of the US examination was evaluated by a fourth blinded rheumatologist. RESULTS: US showed significantly more joints with effusion (mean 15.2) and synovitis (mean 14.6) than clinical examination (mean 11.5, p<0.05). A significant correlation was found between joint count and joint index for swelling, US effusion, synovitis, and PD signal. The 28 joint count for effusion, synovitis, and PD signal correlated highly with the corresponding 60 joint counts. US findings correlated better with CRP and ESR than clinical measures. Interobserver reliability was better for US findings than for clinical assessment. CONCLUSION: US is a sensitive method for assessing joint inflammatory activity in RA, complementary to clinical evaluation.     

Rheumatoid and psoriatic knee synovitis: clinical, grey scale, and power Doppler ultrasound assessment of the response to etanercept

OBJECTIVE: To determine the effect of tumour necrosis factor alpha (TNFalpha) blockade with etanercept in refractory knee joint synovitis (KJS) in rheumatoid and psoriatic arthritis, by local and systemic disease activity assessment and combined grey scale and power Doppler ultrasonographic monitoring. METHODS: 27 knees affected by rheumatoid KJS (n = 12) and psoriatic KJS (n = 8) were assessed before receiving treatment and at 3 and 12 months' follow up. Time dependent clinical changes in disease activity were monitored by C reactive protein, erythrocyte sedimentation rate (ESR), global health status (GHS), and Ritchie (RAI) and knee joint articular (KJAI) indices; synovial changes were monitored by ultrasonographic and power Doppler indices for grey scale synovial thickening and for distinct intrasynovial vessel power Doppler flow configurations (fluid/synovium interface (F/SI-PD) and pannus/cartilage interface (P/CI-PD)). Interobserver and intraobserver variability of grey scale and power Doppler ultrasonographic was evaluated. Response to treatment was assessed by analysis of variance for repeated measures on clinical and ultrasonographic variables. RESULTS: Rapid (3 months) reduction in F/SI-PD flow (p<0.001), parallel to reductions of C reactive protein (p<0.05), ESR (p<0.001), KJAI (p<0.002), RAI, and GHS (p<0.001), was sustained at 12 months when it was accompanied by reduction in both synovial thickening and P/CI-PD flow (p<0.001). No differences (ANOVA) were noted at baseline or at 12 months in clinical and ultrasonographic variables between either the rheumatoid or the psoriatic KJS groups. CONCLUSION: Grey scale and power Doppler ultrasonography are reliable measures of long term change in rheumatoid and psoriatic KJS disease activity in response to anti-TNFalpha treatment with etanercept.     

Macroscopic features of knee synovitis in early untreated Beh?et disease and psoriatic arthritis

In a previous study, we found that synovial immunopathology differs between Behçet disease (BD) and psoriatic arthritis (PsA). The objective of this study is to describe the macroscopic features of early untreated knee synovitis in BD and PsA. Fourteen consecutive patients with active early knee synovitis (seven BD and seven PsA) undergoing rheumatologic arthroscopy were assessed. The following macroscopic synovial features were evaluated and scored by analyzing the video recordings of each procedure: capillary hyperaemia, morphology of synovitis, vascular pattern, fibrinoid membranes, and topographic distribution of these features. Video-recording of 35 early untreated arthritis patients with different diagnoses were also studied looking for BD-like macroscopic features. Six out of seven BD patients had extensive fibrinoid membranes and large areas of erythematous synovitis without villi or a distinctive vascular pattern, while PsA patients had diffuse erythematous villous synovitis with a tortuous vascular morphology. None of the 35 patients with early untreated arthritis exhibited all the characteristic features of BD synovitis. This exploratory study shows some distinctive features between BD and PsA knee synovitis that confirm macroscopic differences in patients with previously reported immunopathological differences.     

Magnetic resonance imaging-determined synovial membrane and joint effusion volumes in rheumatoid arthritis and osteoarthritis. Comparison with the macroscopic and microscopic appearance of the synovium

Objective. To evaluate the relationship between synovial membrane and joint effusion volumes determined by magnetic resonance imaging (MRI) and macroscopic and microscopic synovial pathologic findings in patients with rheumatoid arthritis (RA) and osteoarthritis (OA). Methods. Synovial biopsies were performed, and macroscopic grades of synovitis assigned, at preselected knee sites during arthroscopy or arthrotomy in 17 knees with RA and 25 with OA. Synovial inflammation and 9 separate tissue characteristics were graded histologically. Synovial membrane and joint effusion volumes were determined by preoperative MRI, enhanced with intravenous gadopentetate dimeglumine. Results. MRI-determined synovial membrane volumes were correlated with the overall histologic assessment of synovial inflammation (Spearman's σ = 0.55, P < 0.001), with fibrin deposition, with subsynovial mononuclear and polymorphonuclear leukocyte infiltration (σ = 0.51-0.59), and less significantly with macroscopic synovitis, vessel proliferation, and granulation tissue formation (σ = 0.40-0.42). No correlation with synovial lining multiplication, perivascular edema, villous formation, or fibrosis was found (σ < 0.30). Conclusion. MRI-determined synovial volumes are correlated with synovial inflammatory activity. Synovial volumes probably mainly reflect the mass of cell-infiltrated, vascularized subsynovial tissue, but may also be influenced by the cumulative synovial proliferative activity. MRI-determined synovial membrane and effusion volumes may be sensitive markers and/or predictors of disease activity and treatment outcome in RA.     

Comparison of clinical versus ultrasound‐determined synovitis in juvenile idiopathic arthritis

Objective

To compare clinical evaluation and ultrasonography (US) in the assessment of joint synovitis in children with juvenile idiopathic arthritis (JIA).

Methods

Thirty‐two patients underwent clinical evaluation of 52 joints by 2 pediatric rheumatologists. Joints were assessed for swelling, tenderness/pain on motion, and restricted motion. The same joints were scanned independently by an experienced sonographer for synovial hyperplasia, joint effusion, and power Doppler (PD) signal.

Results

In total, 1,664 joints were assessed both clinically and with US. On clinical examination, 98 joints (5.9%) were swollen, 59 joints (3.5%) were tender, and 40 joints (2.4%) had restricted motion. On US evaluation, 125 joints (7.5%) had synovial hyperplasia, 153 joints (9.2%) had joint effusion, and 53 joints (3.2%) had PD signal. A total of 104 (6.3%) and 167 (10%) joints had clinical and US synovitis, respectively. Of the 1,560 clinically normal joints, 86 (5.5%) had subclinical synovitis (i.e., had synovitis on US). US led to classifying 5 patients as having polyarthritis who were classified as having oligoarthritis or were found to have no synovitis on clinical evaluation. US variables were moderately correlated with clinical measures of joint swelling, but poorly correlated with those of joint tenderness/pain on motion and restricted motion. Overall, correlations were lower for PD signal than for synovial hyperplasia and joint effusion.

Conclusion

We found that subclinical synovitis as detected by US is common in children with JIA. This finding may have important implications for patient classification and may affect the choice of the optimal therapeutic strategy in individual patients.     

Doppler ultrasound measurements of knee joint synovitis in rheumatoid arthritis patients treated with infliximab

Doppler ultrasound measurements were done for the thickness of synovial effusion and synovial proliferation (pannus), and diameter of the flow signals using digital calipers as well as flow signal grades and vascular resistance in the knee joint synovitis of patients with rheumatoid arthritis (RA) treated with infliximab. Forty knee joints of 20 RA patients were assessed before and after three injections of infliximab. The flow signals in the pannus were classified into the superficial and the deep signals and the joints were classified into the superficial signal pattern and the deep signal pattern. After treatment, the number of joints with superficial signal pattern reduced from 23 to 11, whereas the number of joints with deep signal pattern increased from 17 to 29 (P=0.0066), with a significant reduction of the superficial signal grades (P=0.0003). The mean cortical (posterior) pannus thickness increased significantly in the joints with superficial signal pattern (P=0.022) and in the total joints (superficial plus deep signal pattern) (P=0.031) but not in the joints with deep signal pattern. After 6 weeks of treatment with infliximab, the hyperemia in the superficial layer of the pannus developed into proliferation of the cortical pannus in the knee joints.     

Analysis of the histologic variation of synovitis in rheumatoid arthritis

One hundred forty-five synovial biopsy specimens were obtained from 30 procedures performed on the knee joints of 29 patients with rheumatoid arthritis. All patients had clinically active rheumatoid arthritis and none had received slow-acting disease-modifying drugs or intraarticular corticosteroids. Scores were assigned to each biopsy specimen for each of 6 histologic features to quantify variation within each joint. In the majority of knee joint biopsies, there was considerable clustering of scores for all histologic features. Thus, on a scale of 0-10, 82% of the scores for synoviocyte hyperplasia were within 1 point of the median score for a given joint. Similarly, between 69% and 85% of the scores for the remaining features (fibrosis, vessel proliferation, perivascular infiltrates, focal aggregates, and diffuse infiltrates of lymphocytes) were within 1 point of the median values. Multiple biopsies were obtained at arthroscopy in 8 patients. Tissue was selected from areas of apparent maximal and minimal involvement, to enhance the likelihood of regional histologic variation. Of the scores for synoviocyte hyperplasia, 91% were within 1 point of the median values for a given joint, and of the scores for the remaining 5 features, 72-94% fell within 1 point of the median values. In addition, highly significant statistical correlations of the intensity of synovial lining layer hyperplasia, vessel proliferation, mononuclear cell infiltration, fibrosis, and clinical measurements of synovitis were observed.     

Miniarthroscopy of metacarpophalangeal joints in rheumatoid arthritis. Rating of diagnostic value in synovitis staging and efficiency of synovial biopsy.

OBJECTIVE: To evaluate miniarthroscopy (MA) (needle arthroscopy) of involved joints in rheumatoid arthritis (RA) in the early detection and staging of synovitis and its application in visual guided synovial biopsies. METHODS: 1.0 and 1.9 mm (0 degree/30 degrees) arthroscopes were used in a 2 portal technique. MA performance was developed and evaluated first on hand cadavers (n = 20) and then transferred to metacarpophalangeal (MCP) joints under local anesthesia conditions. Joints of 20 patients with RA with different disease activity and duration were scoped and rated according to scores adapted from arthroscopy of other joints. RESULTS: In 20/20 cases MA provided visualizing and magnification of intraarticular features of MCP joints in RA and allowed grading of synovial alterations, chondromalacia, and bony alterations. Synovial surface changes, thickness, and fibrosis were related to disease duration, as was damage to cartilage and bone. The degree of acute inflammatory reactions like vascularity and hyperemia varied independently of chronic changes; synovial proliferation was reflected to some extent by C-reactive protein. In 2 patients with early RA, synovitis criteria were found macroscopically and histologically. In 18/20 joints, biopsies were taken under visual control; in the other 2, progression of disease (Larsen score >3) limited arthroscopy to 1.0 scope imaging only. Sampling sizes were sufficient for histologic and molecular analysis. CONCLUSION: The developed standardized procedure of MCP arthroscopy is minimally invasive, practicable, and well tolerated by patients, and may allow synovitis monitoring, staging, and biopsy in patients with early as well as chronic arthritis.