Sonography of Wrist Ganglion Cysts: Which Location Is Most Common?

Investigations on ultrasonography in the diagnosis of nodular localized cutaneous neurofibroma

OBJECTIVE

To describe the ultrasound characteristics of nodular localized cutaneous neurofibroma (NLCN).

MATERIALS AND METHODS

Clinical features and ultrasound characteristics of 43 lesions of 40 patients pathologically proven as NLCNs at Peking University Shenzhen Hospital from October 2014 to May 2022 were analyzed retrospectively. The location, length-to-thickness (L/T) ratio, thickness-to-width (T/W) ratio, shape, margin, capsule, echogenicity, echotexture, posterior features, vascularity, and "rat tail sign" were evaluated.

RESULTS

All ultrasound findings showed almost perfect agreement. More than a half of NLCNs (n = 24, 55.8%, p < 0.001) were located in the subcutaneous fat layer wholly with well-demarcation from dermis and deep fascia. Most of the NLCNs were fusiform shape (n = 27, 62.8%, p < 0.001) in the long axis and oval shape (n = 35, 81.4%, p < 0.001) in the short axis. The other ultrasound findings of NLCNs included well-defined (n = 42, 97.7%, p < 0.001), encapsulated (n = 39, 90.7%, p < 0.001), predominately hypoechoic (n = 34, 79.1%, p < 0.001), homogeneous (n = 39, 90.7%, p < 0.001), posterior enhancement (n = 29, 67.4%, p = 0.033), and avascularity (n = 37, 86.0%, p < 0.001). Only a quarter (n = 11, 25.6%, p = 0.002) of lesions were recognized with the "rat tail sign."

CONCLUSION

NLCNs present as fusiform shape in long axis and round shape in short axis. The common ultrasound findings of NLCNs are well-defined, encapsulated, predominately hypoechoic, homogeneous lesion with posterior enhancement, and poor blood supply. The "rat tail sign" has low sensitivity in NLCNs.

Diagnostic and Interventional US of the Wrist and Hand: Quadrant-based Approach

Diagnostic and interventional US of the wrist and hand can be challenging due to the small size and superficial location of structures and various disorders that need to be considered. A quadrant-based approach (volar, ulnar, dorsal, and radial) provides a rational method for performing a focused examination and joint positioning during both diagnostic imaging and intervention. Volar wrist disorders primarily involve the median nerve and the digital flexor system comprised of the flexor tendons and pulleys. The ulnar nerve and extensor carpi ulnaris tendon are chiefly responsible for ulnar-sided wrist pain. The differential diagnosis for dorsal-sided symptoms typically involves the extensor tendon compartments and includes distal intersection syndrome, extensor pollicis longus tear, and digital extensor apparatus injury. The soft-tissue ganglion is the most common abnormality in the dorsal wrist, typically associated with wrist ligaments or joint capsule. Radial-sided pain may be secondary to de Quervain tenosynovitis and must be differentiated from the more proximal intersection syndrome. US is an important tool for assessing the ulnar collateral ligament of the first metacarpophalangeal joint of the thumb and differentiating between displaced and nondisplaced tears, thereby influencing management. Despite the complexity of the anatomy and potential pathologic features within the wrist, a focused quadrant-based examination can permit the sonologist to focus on the structures of relevance. In conjunction with a systematic approach, this can aid in precise and efficient diagnostic scanning and intervention of the wrist and hand. ©RSNA, 2023 Supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Visualization of the location and level of pain in common wrist pathologies using color-coded heatmaps

BACKGROUND

Pain of the hand and wrist affects a large patient population. If the onset is unrelated to recent trauma, the first medical contact is rarely established with a specialized hand surgeon.

OBJECTIVE

The objective of this investigation was to (1) visualize the localization of hand pain using pain-related heatmaps in common wrist pathologies, (2) to test whether differences between these pathologies exist with regard to sociodemographic and pain-related aspects, and (3) to evaluate the major patient-reported complaints associated with the pathologies.

METHODS

This observational cross-sectional study included patients suffering from: thumb basal joint arthritis (CMC-1-OA), dorsal wrist ganglions, and TFCC tears. Patients marked the location of maximum pain projection on hand graphics depicting the outline of the palmar and dorsal hand. Color-graded frequency heat maps were generated for the wrist pathologies investigated. Daily life impairments were assessed and clustered into groups of functions/activities.

RESULTS

120 patients with a mean age of 44.3 years were investigated. The diagnostic groups showed significant differences regarding the level and location of pain, as well as daily life impairments. Patients with CMC-1-OA presented with increased pain levels compared to patients with dorsal wrist ganglions and TFCC tears. Daily life impairment was rated highest when household chores were adversely affected, and sport activities were symptomatic/painful. All groups showed significant skin surface pain projection, which was visualized in heatmaps. While general trends in pain localization were visible, pain levels were also reported distal/proximal and palmar/dorsal to the pathology.

CONCLUSIONS

Knowledge of main demographic parameters, pain projection, and degree of impairment in daily activities can help physicians to narrow differential diagnosis of wrist pain during first patient contact. Patients should then be referred to hand surgeons for specialist examination, to further differentiate the origin of the pain.

Two-Year Clinical Outcomes after Arthroscopic Re-Excision of Recurrent Dorsal Wrist Ganglion Cyst

OBJECTIVES

Arthroscopic excision of dorsal wrist ganglion (DWG) cysts has recently become an alternative to open surgery, with the advantage of lower recurrence. However, in recurrent cases, whether re-excision using an arthroscopic approach would achieve favorable outcomes has not been determined. This study aimed to evaluate the clinical outcomes of function evaluation and recurrence rate after arthroscopic excision of recurrent DWG cysts.

METHODS

A total of 11 consecutive patients with clinically diagnosed recurrent DWG cysts were retrospectively reviewed between November 2017 and March 2020. Extensive re-excision of the ganglion cyst and its surrounding pathological capsule was performed using an arthroscopic approach. Magnetic resonance imaging (MRI) was routinely performed before surgery to identify the location and limits of the cyst. All patients were followed up for a minimum of 2 years. A second recurrence was recorded if a mass reappeared at the same site with a positive transillumination test. Pain during activity was evaluated using the visual analog scale (VAS). The active range of motion (ROM) of the wrist was measured using a goniometer, and the hand grip strength was measured using a digital dynamometer. Comparative analysis between the pre- and postoperative indexes was performed using Student's t-test.

RESULTS

After a mean follow-up period of 29.3 months (range, 24-34 months), no second recurrence of the cyst was recorded. The VAS score improved from 1.4 to 0.3 (t = 3.833, p = 0.003), and residual pain was reported by three patients (VAS score = 1 for each). Active wrist flexion increased from 73.6° to 78.2° (t = 2.887, p = 0.016). No significant changes were found in active wrist extension or hand grip strength (p > 0.05). No major complications occurred during the study.

CONCLUSION

Arthroscopic excision of a recurrent DWG cyst yielded satisfactory results with no second recurrence, significant pain relief, and good wrist function at a minimum of 2-year follow-up. Clear identification of the location and limits of the ganglion based on preoperative MRI could be helpful to achieve complete excision and therefore prevent a second recurrence.

Common Ultrasound Applications for Pediatric Musculoskeletal Conditions

PURPOSE OF REVIEW

To discuss the use of ultrasound for diagnosis and management of common pediatric musculoskeletal conditions through a case-based approach.

RECENT FINDINGS

Ultrasound is an essential diagnostic modality in the early detection of developmental dysplasia of the hips and can be used as early as 6 weeks of age when the ossific nucleus has not developed yet. Ultrasound is helpful in diagnosing traumatic injuries such as fractures and intramuscular hematomas, can visualize fracture healing at early stages, and can also be used to guide aspiration of hematomas that can help with decreasing pain and faster recovery. Ultrasound is superior to radiographs in evaluating joint effusions and soft tissue infections or masses and is better tolerated by children compared to other imaging modalities such as magnetic resonance imaging (MRI). Ultrasound is an easily accessible, affordable, non-invasive, and radiation-free imaging modality that is well tolerated by children and their families. It can aid in the diagnosis and management of a wide variety of musculoskeletal conditions including developmental, traumatic, and infectious etiologies, as well as in the evaluation of superficial soft tissue masses.

Ultrasonography of Superficial Soft-Tissue Masses: Society of Radiologists in Ultrasound Consensus Conference Statement

The Society of Radiologists in Ultrasound convened a panel of specialists from radiology, orthopedic surgery, and pathology to arrive at a consensus regarding the management of superficial soft-tissue masses imaged with US. The recommendations in this statement are based on analysis of current literature and common practice strategies. This statement reviews and illustrates the US features of common superficial soft-tissue lesions that may manifest as a soft-tissue mass and suggests guidelines for subsequent management.

Stenosing tenosynovitis of the extensor digitorum tendons of the hand: clinical and sonographic features

OBJECTIVE

To describe the ultrasound (US) features of 18 patients with extensor digitorum communis stenosing tenosynovitis (EDCST).

MATERIALS AND METHODS

A retrospective search in the radiologic information systems of two separate Institutions was performed to identify all patients presenting EDCST between January 2010 and September 2019. A total of 18 patients (ten males and eight females; mean age, 57.4 years) were identified and included. Sonographic examinations were retrospectively reviewed by two senior radiologists to assess morphologic changes and power Doppler activity of the extensor retinaculum (ER) and of the extensor digitorum communis (EDC) tendons and sheath. The presence of dynamic impingement between the EDC and the ER was evaluated using video clip records.

RESULTS

At the ultrasound, all patients (18/18; 100%) presented thickening of both the ER and EDC tendons associated with EDC tendon sheath effusion. Power Doppler hyperemia of the ER was inconstant and observed in 11 cases (11/18; 61.1%) as tendon sheath effusion observed in 16 cases (16/18; 88.9%). A cyst located inside the EDC of the index finger was observed in three of these patients (3/18; 17%). Dynamic examination showed impingement of the EDC against the ER during active tendon extension in all patients (18/18; 100%). Four of these patients (4/18; 22%) underwent surgery allowing diagnosis confirmation and release of EDCST, while the remaining fourteen patients (14/18; 78%) were either treated conservatively or using US-guided steroid injection.

CONCLUSION

US findings of EDCST include thickening of the ER and EDC tendons, EDC tendon sheath effusion, and in some cases presence of an EDC intratendinous cyst. Impingement of the EDC tendons against the ER is well demonstrated using dynamic US.