Peritendinous lesions: the role of high-resolution ultrasonography

MRI of the Achilles tendon-A comprehensive pictorial review. Part one

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Presence of normal septation between subtendons may mimic an intrasubstance tear.

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MRI is superior to ultrasound in detection of partial tears.

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Ultrasound is as useful as MRI in detection of tendinopathy and full-thickness tears.

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Kager's fat pad is involved in infection more than in postoperative changes.

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The Achilles tendon xanthoma has a higher signal on T1- and T2-weighted sequences.

The normal Achilles tendon is composed of twisted subtendons separated by thin high signal septae, which are a potential pitfall on MRI because they mimic a tendon tear.

Tendinopathy and full thickness tears may be assessed effectively both on MRI and ultrasound. MRI is superior to ultrasound in detection of partial tears and for postoperative assessment. The use of fat suppression sequences allows the ability to detect focal lesions. Sagittal and coronal sections are useful for assessing the distance between stumps of a ruptured tendon. Sequences with contrast are indicated in postoperative investigations and suspicion of infection, arthritis or tumor. MRI may reveal inflammatory changes with minor symptoms long before the clinical manifestations of seronegative spondyloarthropathy. The most common non-traumatic focal lesion of the Achilles tendon is Achilles tendon xanthoma, which is manifested by intermediate or slightly higher signal on T1- and T2-weighted images compared to that in the normal Achilles tendon. Other tumors of the Achilles tendon are very rare, whereas the involvement of the tendon from tumor in adjacent structures is more frequent.

The novel MRI sequences may help to detect disorders of the Achilles tendon more specifically before clinical manifestation. Regeneration or remodeling of the Achilles tendon can be non‐invasively detected and monitored in diffusion tensor imaging. Assessment of healing is possible using T2-mapping while evaluating the tendon vascularization in intravoxel incoherent motion MRI.

Coexistent digital gouty and infective flexor tenosynovitis

Flexor tenosynovitis of the hand is often caused by trauma or infection. Gouty tenosynovitis is an uncommon presentation of the condition and is usually misdiagnosed as infection with the patient undergoing surgery. The coexistence of infection and gout causing flexor tenosynovitis has never been described before in the literature; we report the first ever case and emphasise the importance of its awareness for optimal treatment. A 54-year-old man was initially diagnosed and treated as having infective flexor tenosynovitis and, later, due to a lack of improvement in his symptoms, was discovered to also have gout. We review the literature and suggest management strategy for use in daily clinical practice, including an algorithm, for this presentation.

Olecranon bursitis

BACKGROUND

Bursitis is a common medical condition, and of all the bursae in the body, the olecranon bursa is one of the most frequently affected. Bursitis at this location can be acute or chronic in timing and septic or aseptic. Distinguishing between septic and aseptic bursitis can be difficult, and the current literature is not clear on the optimum length or route of antibiotic treatment for septic cases. The current literature was reviewed to clarify these points.

METHODS

The reported data for olecranon bursitis were compiled from the current literature.

RESULTS

The most common physical examination findings were tenderness (88% septic, 36% aseptic), erythema/cellulitis (83% septic, 27% aseptic), warmth (84% septic, 56% aseptic), report of trauma or evidence of a skin lesion (50% septic, 25% aseptic), and fever (38% septic, 0% aseptic). General laboratory data ranges were also summarized.

CONCLUSIONS

Distinguishing between septic and aseptic olecranon bursitis can be difficult because the physical and laboratory data overlap. Evidence for the optimum length and route of antibiotic treatment for septic cases also differs. In this review we have presented the current data of offending bacteria, frequency of key physical examination findings, ranges of reported laboratory data, and treatment practices so that clinicians might have a better guide for treatment.

Ultrasound features of tophi in chronic tophaceous gout

OBJECTIVE

To describe the different and lesser-known ultrasound features of tophi in chronic tophaceous gout.

METHODS

Ultrasound images of 138 affected areas were analyzed from 31 patients with gout, using high-quality broadband linear transducers (frequency range of 8-14 MHz). Tophi were classified relative to echogenicity, echotexture, contours, number and the presence or absence of hypoechoic halo. The duration of illness was correlated with the presence of calcifications in tophi.

RESULTS

Hyperechoic tophi were seen in 133 areas (96.3%); these were most frequently hyperechoic and heterogeneous (37.6%) or hyperechoic and heterogeneous with calcification (32.6%). Contours were found to be poorly defined in 115 (83.3%) areas. Multiple grouped tophi were seen in 85 areas (61.6%) and 50 areas (36.2%) had individual tophi. In 77 examined areas (55.8%), there was a hypoechoic halo around the tophi. There was no correlation between illness duration and presence of calcifications on tophi.

CONCLUSIONS

Tophi are generally hyperechoic, heterogeneous, with poorly defined contours, multiple grouped and surrounded by an anechoic halo. Individual tophus and the absence of association between illness duration and the presence of calcification are newly described features. This study of tophaceous gout by ultrasound may contribute to the diagnostic elucidation of patients with clinically atypical gout and show its diverse characteristic forms of presentation.

Sonographic description and classification of tendinous involvement in relation to tophi in chronic tophaceous gout

Objective

To describe and classify the varied ultrasound features of tendinous involvement in relation to tophi in chronic tophaceous gout so that they are better recognised.

Methods

Ultrasound images of 138 affected areas from 31 patients with chronic tophaceous gout were analysed using high-quality broadband linear transducers. The relationship between tendon and tophi was classified, and the inter-observer agreement regarding classification was analysed.

Results

Tophi envelopment in the tendon was the most frequent characteristic (45%) followed by no relationship between tophi and tendon (41%), tophi at the insertion site of the tendon (7%), extrinsic compression (6%) and tophi within the tendon (1%). The inter-observer concordance on classification of the relationship between tophi and tendon was measured using McNemar’s test with P < 0.001 (χ² = 30.0, degree of freedom = 9) and kappa test = 0.627 (P < 0.001), indicating substantial inter-observer concordance.

Conclusion

Tophi generally envelope the tendon or there is no relationship between them. Tophi can also be found at the insertion site of the tendon, cause extrinsic compression or be located inside the tendon. There is substantial inter-observer agreement for ultrasound classification of tendon involvement by tophi. This study contributes to diagnostic elucidation and shows the diverse characteristic forms of tendon involvement by tophi.

Imaging of giant cell tumour of the tendon sheath

Giant cell tumours of the tendon sheath (GCTTS) and pigmented villonodular synovitis (PVNS) are part of a spectrum of benign proliferative lesions of synovial origin that may affect the joints, bursae and tendon sheaths. This review article describes the clinicopathological features and imaging findings in patients with GCTTS. GCTTS usually presents as a soft tissue mass with pressure erosion of the underlying bone. Magnetic resonance (MR) imaging of GCTTS typically shows low to intermediate signal on T1- and T2-weighted spin-echo sequences due to the presence of haemosiderin, which exerts a paramagnetic effect. On gradient-echo sequences, the paramagnetic effect of haemosiderin is further exaggerated, resulting in areas of very low signal due to the blooming artefact. Ultrasonography shows a soft mass related to the tendon sheath that is hypervascular on colour or power Doppler imaging.

Pigmented villonodular synovitis of the talonavicular joint: a case report and review of the literature

Pigmented villonodular synovitis (PVNS) is a locally aggressive synovial proliferative disorder of unknown aetiology affecting the linings of joints, tendon sheaths, and bursae. A 22-year-old female patient presented with a 3-year history of an increasingly painful swelling on the dorsum of her right foot. Examination revealed a 4 cm x 2 cm swelling that was fluctuant, tender on palpation, unattached to overlying skin and partially mobile. A firm, pedunculated intra-articular lesion from the talonavicular joint was removed at surgery. Histology revealed a nodular lesion of stromal cells and numerous giant cells with villous architecture as well as abundant haemosiderin deposition with foamy macrophages (in keeping with PVNS). The patient is currently under review by the orthopaedic oncology team. Talonavicular joint PVNS is rare. MRI scanning is the optimum investigation. Complete excision is necessary to minimise high risk of recurrence.

Carpal bone involvement in gout

The deposition of gout tophi in the hand occurs relatively late in the disease. Involvement of carpal bone is rarely reported in the literature. We present a 40-year-old man with a long duration of gouty arthritis involving the carpal bones.

Diagnostic imaging of gout: comparison of high-resolution US versus conventional X-ray

The aim was to compare X-ray and ultrasound (US) in diagnosing gout. In a prospective study, 105 consecutive patients with clinical suspicion of gout underwent conventional X-ray und high-resolution US in order to help in arriving at a definite diagnosis. X-ray findings suggestive of gout included soft-tissue opacifications with densities between soft tissue and bone, articular and periarticular bone erosions, and osteophytes at the margins of opacifications or erosions. US findings suggestive of gout included bright stippled foci and hyperechoic soft-tissue areas. Fifty-five patients had a definite diagnosis of gout (102 involved sites), 31 patients were diagnosed as having another disease (59 involved sites), and 19 patients were excluded from the study because a definite diagnosis could not be established. X-ray suggested gout with a sensitivity of 31% (32/102) and a specificity of 93% (55/59), whereas US suggested gout with a sensitivity of 96% (98/102) and a specificity of 73% (43/59). US was much more sensitive than conventional X-ray but less specific. Our data show that US often provided additional diagnostic information in patients with clinical suspicion of gout when laboratory findings and X-ray results were negative or inconclusive and should therefore be used in these cases.

The value of sonography in diagnosing giant cell tumors of the tendon sheath

OBJECTIVE

The purpose of this study was to evaluate the diagnostic value of sonography in giant cell tumors of the tendon sheath.

METHODS

Sonographic findings and other clinical records were retrospectively reviewed and analyzed in 30 patients (45 lesions) with pathologically proven giant cell tumors of the tendon sheath. The sonographic findings were compared with those found at surgery.

RESULTS

The locations of the tumors included the hand (53.33%), wrist (10%), elbow (3.33%), knee (10%), and foot (23.33%). The sizes of the tumors ranged from 0.4 to 8 cm, with a mean size of 2.6 cm. All the lesions were shown as hypoechoic nodules with homogeneous or heterogeneous echogenicity. Thirty-two lesions (71.11%) had substantial flow, and 13 lesions (28.89%) had minimal flow. Thirty-four lesions were in contact with the tendon sheath; 5 were in contact with the joint; and 6 were in contact with both the tendon sheath and the joint. Bone erosions were found in 4 cases, and bone impressions were found in another 3 cases.

CONCLUSIONS

Sonography can provide exact information about a tumor and its relationship with the surrounding tissue, which indicates that it can be used as the first method to diagnose a giant cell tumor of the tendon sheath.

[Interventional sonography]

Diagnostic and therapeutic interventional procedures are rapidly expanding and, when guided by imaging, are more efficient then when performed with a blinded technique. Compared to fluoroscopy and CT, ultrasound does not utilize ionizing radiation. It can facilitate needle placement for arthrography, tenography or bursography or it can guide a variety of procedures such as aspiration, arthrocentesis, local steroid injections and needling of tendon calcifications. Technological improvements have increased the precision of ultrasound guidance and have contributed to reduce the risk of complication. Real time scanning allows simultaneous visualization of the target and of needle progression and has diminished the rate of complications, that are infrequent if the operator uses a strict sterile technique and respects the contraindications.

Giant Cell Tumors of the Tendon Sheath: Analysis of Sonographic Findings

OBJECTIVE

The purpose of this study was to analyze the sonographic characteristics of giant cell tumors of the tendon sheath.

CONCLUSION

Giant cell tumors of the hand typically appear as solid, homogeneous hypoechoic masses with detectable internal vascularity that are associated with the flexor tendons of the fingers.