Finger tendon disease in untreated early rheumatoid arthritis: a comparison of ultrasound and magnetic resonance imaging.

OBJECTIVE: To investigate the frequency and distribution of finger tenosynovitis in patients with early, untreated rheumatoid arthritis (RA) using gray-scale ultrasound (US) and magnetic resonance imaging (MRI). METHODS: Fifty patients underwent US and MRI of metacarpophalangeal (MCP) joints 2-5. Twenty healthy controls underwent US only. Flexor and extensor involvement was documented for each joint. Intrareader reliability (IRR) was calculated by rereading static images. RESULTS: Flexor tenosynovitis was found in 57 (28.5%) of 200 joints in 24 (48%) of 50 patients on US compared with 128 (64%) of 200 joints in 41 (82%) of 50 patients on MRI. Periextensor tenosynovitis was found in 14 (7%) joints in 9 (18%) patients on US compared with 80 (40%) joints in 36 (72%) patients on MRI. No controls had imaging tenosynovitis. Using MRI as the gold standard, the sensitivity, specificity, and negative and positive predictive values for US were 0.44, 0.99, 0.49, and 0.98, respectively, for flexor tenosynovitis and 0.15, 0.98, 0.63, and 0.86 for extensor tenosynovitis, respectively. The IRR was 0.85 and 0.8 for US and MRI, respectively. The most frequently involved joints on US and MRI were the second and third MCP joints. CONCLUSION: This is the first study to compare US and MRI for the detection of tenosynovitis in the fingers of patients with early untreated RA. Tenosynovitis was found to be common using both modalities, with MRI being more sensitive. A negative US scan does not exclude inflammation and an MRI should be considered. Further work is recommended to standardize definitions and image acquisition for both US and MRI images.

Magnetic resonance imaging study of cross-sectional area of the cervical extensor musculature in an asymptomatic cohort.

Magnetic Resonance Imaging (MRI) can be regarded as the gold standard for muscle imaging; however there is little knowledge about in vivo morphometric features of neck extensor muscles in healthy subjects and how muscle size alters across vertebral segments. It is not known how body size and activity levels may influence neck muscle cross-sectional area (CSA) or if the muscles differ from left and right. The purpose of this study was to establish relative CSA (rCSA) data for the cervical extensor musculature with a reliable MRI measure in asymptomatic females within a defined age range and to determine if side-side and vertebral level differences exist. MRI of the cervical spine was performed on 42 asymptomatic female subjects within the age range of 18-45. The rCSA values for the cervical extensor muscles were measured from axial T1-weighted images. We found significant side-side rCSA differences for the rectus capitis posterior minor, major (P < 0.001), multifidus (P = 0.002), and the semispinalis cervicis/capitis (P = 0.001, P < 0.001). There were significant vertebral level differences in rCSA of the semispinalis cervicis/capitis, multifidus, splenius capitis, and upper trapezius (P < 0.001). Activity levels were shown to impact on the size of semispinalis cervicis (P = 0.027), semispinalis capitis (P = 0.003), and the splenius capitis (P = 0.004). In conclusion, measuring differences in neck extensor muscle rCSA with MRI in an asymptomatic population provides the basis for future study investigating relationships between muscular atrophy and symptoms in patients suffering from persistent neck pain. Clin.

Magnetic resonance imaging analysis of the upper cervical spine extensor musculature in an asymptomatic cohort: an index of fat within muscle.

AIM: To establish a simple method to quantify muscle/fat constituents in cervical muscles of asymptomatic women using magnetic resonance imaging (MRI), and to determine whether there is an age effect within a defined age range. MATERIALS AND METHODS: MRI of the upper cervical spine was performed for 42 asymptomatic women aged 18-45 years. The muscle and fat signal intensities on axial spin echo T1-weighted images were quantitatively classified by taking a ratio of the pixel intensity profiles of muscle against those of intermuscular fat for the rectus capitis posterior major and minor and inferior obliquus capitis muscles bilaterally. Inter- and intra-examiner agreement was scrutinized. RESULTS: The average relative values of fat within the upper cervical musculature compared with intermuscular fat indicated that there were only slight variations in indices between the three sets of muscles. There was no significant correlation between age and fat indices. There were significant differences for the relative fat within the muscle compared with intermuscular fat and body mass index for the right rectus capitis posterior major and right and left inferior obliquus capitis muscles (p=0.032). Intraclass correlation coefficients for intraobserver agreement ranged from 0.94 to 0.98. Inter-rater agreement of the measurements ranged from 0.75 to 0.97. CONCLUSION: A quantitative measure of muscle/fat constituents has been developed, and results of this study indicate that relative fatty infiltration is not a feature of age in the upper cervical extensor muscles of women aged 18-45 years.

Interobserver variation in sonography of the painful shoulder.

PURPOSE: This study was conducted as a prospective assessment of interobserver variability in the sonographic evaluation of the rotator cuff. METHODS: Three musculoskeletal radiologists who had different levels of scanning experience each performed shoulder sonography on 24 consecutive patients during 1 patient visit. The diagnostic criteria full-thickness rotator cuff tear, tendon calcification, tendinosis of the supraspinatus, subacromial fluid, subacromial synovial/bursal thickening, dynamic signs of impingement, and abnormality in the long head of biceps tendon were scored, with independent observers recording the data. Statistical analysis was performed using Cohen's kappa test, with significance assessed at p values of less than 0.05. RESULTS: There was good agreement (kappa >0.60, p <0.01) between the experienced operators for full-thickness rotator cuff tear, tendon calcification, dynamic signs of impingement, and abnormality of the long head of biceps tendon. There was no significant agreement between the experienced operators and the less experienced operator in several categories, including (and importantly) full-thickness rotator cuff tears (kappa=0.18-0.21). CONCLUSIONS: In experienced hands sonography of the rotator cuff is a reproducible diagnostic test, but agreement is poor when there is marked disparity between the operators' experience levels. Our findings suggest a need for a more clearly defined training curriculum for sonography of the shoulder in radiology training programs.

Should oligoarthritis be reclassified? Ultrasound reveals a high prevalence of subclinical disease.

OBJECTIVE: To determine the prevalence of subclinical synovitis using ultrasound (US) imaging of both painful and asymptomatic joints, in patients with early (<12 months), untreated oligoarthritis (6 joints). Of the 826 asymptomatic (non-painful) joints scanned, 13% (107/826) had US detected synovitis. CONCLUSION: Sonography detected more synovitis than clinical examination in patients with oligoarthritis. In almost two thirds of patients there was evidence of subclinical disease while one third could be reclassified as polyarticular. These findings suggest that a definition of oligoarthritis based purely on clinical findings may be inappropriate, which may have important implications for disease management.

Comparative assessment of leflunomide and methotrexate for the treatment of rheumatoid arthritis, by dynamic enhanced magnetic resonance imaging.

OBJECTIVE: Ethical constraints on the conduct of placebo-controlled trials evaluating new therapies for serious chronic diseases, such as rheumatoid arthritis (RA), indicate the need for discerning methods to assess treatment effect in active-controlled clinical trials. Dynamic gadolinium-enhanced magnetic resonance imaging (DEMRI) is a sensitive technique for the detection of synovial inflammation in RA. Therefore, this investigation was undertaken to evaluate DEMRI as an efficacy assessment tool for differentiating treatment effect in a randomized, active-controlled trial comparing leflunomide and methotrexate. METHODS: Patients with active RA (n = 39) were randomized in a 2-center, prospective, double-blind clinical trial to receive either leflunomide (n = 18) or methotrexate (n = 21) therapy for 4 months. DEMRI scans were obtained at baseline and at 4 months, and the initial rate of enhancement (IRE) and the maximal signal intensity (SI) enhancement (ME) were calculated from the SI curves. Clinical improvement was assessed by conventional outcome measures. RESULTS: Thirty-four patients (17 treated with leflunomide and 17 with methotrexate) had usable baseline and end point DEMRI scans. Leflunomide treatment was associated with a significantly greater improvement in IRE compared with methotrexate treatment (P < 0.05). Average values of ME indicated reduction of inflammation with both leflunomide and methotrexate. The improvement in clinical signs and symptoms, as measured by traditional assessments, was comparable for both active treatments. CONCLUSION: Results of this study validate the sensitivity of DEMRI in detecting inflammatory changes in active RA in response to treatment. Improvement in synovial inflammation as measured by IRE was significantly better with leflunomide than with methotrexate over 4 months of therapy.

Distribution of sonographically detected tendon abnormalities in patients with a clinical diagnosis of chronic achilles tendinosis.

PURPOSE: We conducted a retrospective study of the distribution of sonographically detected abnormalities in the heels of patients who had a clinical diagnosis of Achilles tendinosis. METHODS: One hundred eighteen symptomatic heels in 73 patients who had a clinical diagnosis of chronic Achilles tendinosis were examined over a 12-month period by the same experienced sonologist. The distribution of altered tendon architecture and features suggesting retrocalcaneal bursitis or Achilles paratendinosis were evaluated. RESULTS: Sonograms of 118 symptomatic heels demonstrated that 96 (81%) had abnormalities confined to the proximal two thirds of the Achilles tendon, 9 (8%) had abnormalities in the distal third alone, and 13 (11%) had abnormalities at both sites. Of the 109 heels with proximal two-third Achilles tendon disease, 99 (91%) had medial tendon involvement; 22 of the 99 showed diffuse tendon changes. Lateral tendon segment changes were seen in 22 (19%) of the 118 symptomatic heels. No lateral tendon segment was involved in isolation. Of the 22 heels with distal third abnormalities, 14 (64%) had sonographic evidence of Achilles paratendinitis, and 13 (59%) had sonographic evidence of Achilles tendinosis. Eighteen of the 22 had sonographic evidence of retrocalcaneal bursitis. In all cases of distal third tendinosis, the deep surface of the tendon was primarily involved. In the heels with both proximal and distal changes, superficial segment involvement of the mid-Achilles tendon was present. CONCLUSIONS: Sonography provides information that helps to accurately diagnose clinical Achilles tendinopathy and may help to determine the biomechanical processes involved in the injury.

The value of sonography in the detection of bone erosions in patients with rheumatoid arthritis: a comparison with conventional radiography.

OBJECTIVE: The ability to make an early, accurate diagnosis of rheumatoid arthritis (RA) has become increasingly important with the availability of new, expensive, and targeted therapies. However, plain radiography, the traditional method of detecting the characteristic bone erosions and an important adjunct in establishing a diagnosis of RA, is known to be insensitive. This study compared sonography, a modern imaging technique, with conventional radiography for the detection of erosions in the metacarpophalangeal (MCP) joints of patients with RA. METHODS: One hundred RA patients (including 40 with early disease) underwent posteroanterior radiography and sonography of the MCP joints of the dominant hand. Twenty asymptomatic control subjects also underwent sonography. Erosion sites were recorded and subsequently compared using each modality. Magnetic resonance imaging (MRI) was performed on the second MCP joint in 25 patients with early RA to confirm the pathologic specificity of sonographic erosions. Intraobserver reliability of sonography readings was assessed using video recordings of 55 MCP joint scans of RA patients, and interobserver reliability was assessed by comparing 160 MCP joint scans performed sequentially by 2 independent observers. RESULTS: Sonography detected 127 definite erosions in 56 of 100 RA patients, compared with radiographic detection of 32 erosions (26 [81%] of which coincided with sonographic erosions) in 17 of 100 patients (P < 0.0001). In early disease, sonography detected 6.5-fold more erosions than did radiography, in 7.5-fold the number of patients. In late disease, these differences were 3.4-fold and 2.7-fold, respectively. On MRI, all sonographic erosions not visible on radiography (n = 12) corresponded by site to MRI abnormalities. The Cohen-kappa values for intra- and interobserver reliability of sonography were 0.75 and 0.76, respectively. CONCLUSION: Sonography is a reliable technique that detects more erosions than radiography, especially in early RA. Sonographic erosions not seen on radiography corresponded to MRI bone abnormalities. This technology has potential in the management of patients with early RA/inflammatory arthritis and is likely to have major implications for the future practice of rheumatology.

Ultrasound in inflammatory disease.

US may be used effectively to diagnose and treat a wide range of musculoskeletal inflammatory conditions. It is likely that its usage will increase with regards to such conditions especially in the management of rheumatology clinic patients.

Sonographic incidence of tendon microtears in athletes with chronic Achilles tendinosis.

OBJECTIVE: To assess the number and distribution of tendon microtears in asymptomatic controls and athletes with chronic Achilles tendinitis or partial thickness tears using high resolution ultrasound. METHODS: The mean number of microtears in three random tendon cross sections were recorded per tendon third in 19 asymptomatic volunteers, 16 athletes with symptomatic chronic Achilles tendinitis, and eight athletes with partial Achilles tendon rupture. RESULTS: Microtears were most numerous in the middle third section of the Achilles tendon. Some 67% of tendons in the control group had no microtears, and 28% showed a single microtear. Only 18% of the athletes with chronic Achilles tendinitis and none of the athletes with partial tendon rupture were without microtears in the middle third of their Achilles tendon. Of the tendons with chronic tendinitis, 13% had more than three microtears per section which increased to 87% in tendons exhibiting partial rupture. CONCLUSIONS: There appears to be an association between microtear formation and Achilles tendon rupture.

Ultrasound of the plantar aponeurosis (fascia).

OBJECTIVE: To assess the plantar aponeurosis origin (plantar fascia) using high-resolution ultrasound. DESIGN: The sonographic appearance of the plantar fascia in asymptomatic volunteers was compared with the appearance in: (1) clinical idiopathic plantar fasciitis, (2) inflammatory arthropathy without clinically active plantar fasciitis and (3) Achilles tendon or ankle ligament injury. Patients. There were 48 asymptomatic volunteers (96 heels), 190 patients with idiopathic plantar fasciitis (297 heels), 35 with rheumatoid factor negative spondyloarthropathy (70 heels), 17 with rheumatoid arthritis (34 heels), 62 with clinical Achilles tendinitis (93 heels) and 17 with instability secondary to previous ankle ligament injury (17 heels). RESULTS: Compared with the asymptomatic volunteers, the symptomatic plantar aponeurosis demonstrated significant thickening in patients with clinically unilateral (P<0.001) and bilateral (P<0.001) idiopathic plantar fasciitis as well as in patients with spondyloarthropathy (P<0.001). However, the plantar aponeurosis on the asymptomatic side in patients with unilateral idiopathic plantar fasciitis (P<0.2), rheumatoid arthritis (P<0.2) and ankle injury (P<0.1) demonstrated no significant thickening. In patients with idiopathic plantar fasciitis, abnormal plantar aponeurosis echogenicity was seen in 78% and subcalcaneal bone spurs in 24%. Peritendinous edema was present in 5% of all symptomatic heels, subcalcaneal bone erosion in 4% and intratendinous calcification in 3% of heels. Retrocalcaneal bursitis was present in 7% of patients with idiopathic plantar fasciitis, 40% with spondyloarthropathy and 19% with rheumatoid arthritis. CONCLUSION: Ultrasound allows confirmation of the clinical diagnosis in plantar fasciitis and may provide information as to its etiology.

Magnetic resonance imaging of injuries in the child athlete.

Sports related injuries in children and adolescents are an increasingly frequent clinical problem. Soft tissue injury is relatively less common in children than in adults and radiographs suffice in most situations. However there are specific clinical circumstances where MR imaging is of value. We discuss and demonstrate a variety of acute and chronic sports related conditions where MR imaging has contributed to the diagnosis and management. Some conditions such as apophysitis, osteochondritis and chronic physeal injuries are unique to childhood while others including spondylysis and stress fractures are unusual conditions outside the context of sport in this age group.