Wrist ultrasound examination - scanning technique and ultrasound anatomy. Part 1: Dorsal wrist

Introducing the Foveola lunata, an anatomical landmark of the wrist

The lunate foveola is often the starting point of a cystic swelling called a "ganglion". To make the anatomy of this region more relevant to the needs of clinicians and more accessible to students, we propose to introduce the term lunate foveola (Foveola lunata) on the dorsal side of the wrist just distal to the os lunatum. The easily located foveola will help in the examination of the wrist to more easily understand the anatomy of the wrist and facilitate the examination of patients with wrist injuries when an injury to the lunate (Os lunatum) is suspected.

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.

Case report: Flexor carpi ulnaris tendinopathy in a lure-coursing dog treated with three platelet-rich plasma and platelet lysate injections

In the present case report a 7-year-old male Whippet competing in lure-coursing presented with third-degree recurrent lameness of the right forelimb, pain on palpation of the caudal aspect of the carpus and swelling of the forearm proximally to the accessory carpal bone. Clinical, radiographic, and ultrasonographic evaluation diagnosed a flexor carpi ulnaris (FCU) chronic tendinopathy unresponsive to previously attempted conservative treatments such as oral non-steroidal anti-inflammatory drugs (NSAIDs) administration along with padded palmar splint application and rest. The dog was subjected to one injection of autologous platelet-rich plasma (PRP) obtained using a double centrifugation tube method, followed by two platelet lysate (PL) injections. Treatment was administered at three-week intervals. The healing process was assessed through clinical and ultrasonographic imaging (US) on the day of the first injection (T0), and at week three (T1), six (T2), twelve (T3), fifty-two (T4), and one-hundred-and-four (T5). Fiber alignment score (FAS) and echogenicity score (ES) were developed by modifying a previously published US assessment scale. At T1, ES, and FAS improvement was detected, and at T2, further improvements in ES and FAS were observed. Ultrasonographic results were clinically consistent with the improvement in lameness: lameness grade 3/4 was detected at T0 and grade 2/4 at T1. A lameness grade of 1/4 was detected at T2, and grade 0/4 was observed at T3, T4, and T5. Moreover, at T5, the dog returned to competition, and no history of re-injury was reported. Our results suggest that the treatment of FCU tendinopathy in lure-coursing dogs with a combination of consecutive injections of autologous PRP and PL could be feasible. Additionally, no adverse reactions were observed.

Dorsal scapholunate interosseous ligament: ultrasound evaluation between dominant and non-dominant wrist in young sports patients

PURPOSE

The dorsal component of the scapholunate ligament, is the strongest component, in fact it has a maximum tensile strength of 300 N and mainly controls flexion and extension. In a recent study, the thickness and length of the dorsal component of SLIL was measured using ultrasound image, the length of the dorsal scapholunate ligament was 7.5 mm ± 1.4 mm and the thickness of 1.8 mm ± 0.4 mm. We evaluate 60 wrists of 30 young athletic volunteers with ultra-sound image, comparing the thickness variations of the dorsal component of SLIL between the dominant and non-dominant wrist, to confirm our hypothesis that the dorsal component SLIL has proprioceptive activity and therefore the thickness of the ligament increases in following wrist activity.

METHODS

With a high-frequency ultrasound probe > 15 MHz (Sonoscape X3 Pro) we evaluated 60 wrists of 30 young men (16 males and 14 females, 20-38 years old) manual sports volunteers (10 tennis players, 8 padel players, 7 swimmers, 5 weight lifters) with no recent ligament injuries of the hand or wrist to participate in the study, we compared the dorsal component of SLIL between the dominant and non-dominant wrist.

RESULTS

Dorsal SLIL was visualized in all 60 volunteers wrists. We measured an average scapholunate dorsal ligament length 7.7 mm and average thickness of 2.3 mm in the dominant wrist and average 7.2 mm in length and average 1.9 mm thickness in the non dominant wrist. The mean dorsal scapholunate interval was average 4.9 mm and the mean central interval was average 2.1 mm in the dominant wrist and 4.7 mm and 1.8 mm in the non dominant wrist, so that meas-urements remained unchanged with those reported by previous authors.

CONCLUSIONS

In our study we ultrasonographically measured an average scapholunate dorsal ligament length 7.7 mm and average thickness of 2.3 mm in the dominant wrist and average 7.2 mm in length and average 1.9 mm thickness in the non dominant wrist. This confirms our hypothesis that there is a direct stimulus on the ligamentous component of the dor-sal SLIL in the dominant wrist following repeated uses and activities such as to cause an increase in thickness of the dorsal ligament to highlight the possibility of a proprioceptivity of the ligament if subjected to continuous training.

LEVEL OF EVIDENCE

IV.

High-Resolution Ultrasonographic Anatomy of the Carpal Tendons of Sporting Border Collies

Recent literature has demonstrated that high-resolution ultrasonographic anatomy of the canine carpus is possible; however, only the structures of the dorsal face were described. The aims of this prospective study were: (1) to describe the normal ultrasonographic appearance of the carpal tendons in sporting Border Collies; (2) to measure the height, length, and thickness of the tendon at the radial ulnar notch level in order to create a baseline reference for the breed, and (3) to describe a standardised protocol to ultrasonographically evaluate the carpal faces and visible tendinous structures. A pilot study based on ten cadaveric front limbs was used to identify the structures. A subsequent clinical phase of the study using twenty-six Border Collies was recorded. The tendons of the Extensor Carpi Radialis, Extensor Digitorum Communis, and Extensor Digitorum Lateralis were identified and followed from the tenomuscular junction to the distal insertion on the dorsal face of the digits. On the lateral face, the tendon of the Extensor Carpi Ulnaris was recognised and followed. On the palmar face, the two heads of the Flexor Carpi Ulnaris tendon ending on the accessory carpal bone, the adjacent Flexor Digitorum Superficialis tendon, and the deep and medially located Flexor Digitorum Profundus tendon were seen and followed. The Flexor Carpi Radialis and the Abductor Pollicis Longus tendons were seen in the medial carpal face. The ulnar notch of the radius was used as the measurement and starting point of the ultrasonography. These data could be used as a standard reference in the case of chronic overuse and trauma-induced changes in the canine carpus.

Usefulness of the Ultrasound in Hand Surgery: Part I

In the last years, ultrasonography (US) of the wrist and hand have increased in popularity. Technical advances led us to improve image quality and have the ability to see superficial soft-tissue structures with high resolution with the patient in our office.

The advantages of US are the fact that it is noninvasive, its lack of ionising radiation, low cost, and portability. The dynamic real-time assessment in the office is an additional benefit.

Ultrasound can be used in hand surgery for both diagnostic and therapeutic purposes. We can use US for injections with needle guidance, for the evaluation of soft-tissue masses, foreign bodies, tendon injuries, compressive neuropathies, and rheumatologic joint disease. It also helps us perform ultrasound-guided procedures: carpal tunnel syndrome, trigger finger, and intersection syndrome or compartimental syndrome.

The aim of the present review is to describe different uses of US in hand surgery to show its important role of providing to the surgeon more information on the diseases of their patients.

Ultrasound evaluation of the scapholunate ligament and scapholunate joint space in patients with wrist complaints in a rheumatologic setting

Aim

The aims of the study were to perform an ultrasound assessment of the dorsal portion of the scapholunate interosseous ligament and scapholunate joint space in patients with wrist complaints in a rheumatologic setting, to describe ultrasound abnormalities about scapholunate interosseous ligament region, and to correlate them with clinical data, presence of dorsal ganglion cysts and diagnoses of rheumatic diseases.

Material and methods

Seventy-four consecutive patients with wrist pain and/or swelling were evaluated by routine power Doppler ultrasound. Forty normal wrists were studied to confirm the normality values of the scapholunate joint.

Results

The mean width of the normal scapholunate joint was 2.49 mm (±0.49 SD), with a coefficient of variation on repeated measurements of 3.662%. The best predictors of scapholunate interosseous ligament degeneration were: older age (p <0.0001), male gender (p = 0.0049), and radiocarpal effusion (p = 0.0156). The presence of osteophytosis and calcifications of the scapholunate joint were higher (p <0.001) in rheumatic patients. Scapholunate calcifications showed a sensitivity of 98.2% and a specificity of 61.1% for calcium pyrophosphate deposition disease. Dorsal ganglion cysts were more frequent in younger subjects (p <0.0012) without rheumatic conditions (p <0.0001) or midcarpal synovitis (p <0.0001). Larger cysts often exhibited power Doppler signal (p <0.0001). The best predictors of scapholunate dissociation were: male gender (p = 0.0002), presence of midcarpal synovitis (p <0.0137), and higher grade of scapholunate interosseous ligament degeneration (p <0.0001). Scapholunate widening was greater (p = 0.0419) in calcium pyrophosphate deposition disease or rheumatoid arthritis than in other rheumatic conditions.

Conclusions

Ultrasound findings of scapholunate interosseous ligament degeneration and calcification, scapholunate space enlargement, and dorsal ganglion cysts should be considered in ultrasound reporting, since they add useful information about the diagnosis of associated rheumatic conditions.

What is the role of ultrasonography in the early diagnosis of scaphoid fractures?

Scaphoid fractures are the most prevalent type of carpal bone fractures. High-spatial-resolution sonography detects direct signs of scaphoid fractures such as scaphoid cortical disruption; nevertheless, indirect signs such as radiocarpal effusion and scapho-trapezium-trapezoid effusion can also be visible. The diagnosis is performed when both direct and indirect signs of scaphoid fracture are presented. The presence of indirect signs alone is not enough to complete the diagnosis, for which more advanced imaging modalities are usually required. Here, we review the anatomy of the scaphoid, the clinical manifestations of scaphoid fractures, as well as ultrasonographic findings and differential diagnosis.

Feasibility of Ultrasound in Infant Wrist and Thumb Imaging

OBJECTIVES

To determine the feasibility of ultrasound (US) in infant lateral carpal and base-of-the-thumb imaging. We hypothesized that US would be a practical modality for visualizing the unossified structures.

METHODS

Institutional review board approval was obtained for this single-center pilot study. Healthy infants aged 12 months or younger were enrolled. Ultrasound examinations of the distal radial epiphysis through the first metacarpal were performed with a high-frequency transducer.

RESULTS

Ultrasound evaluations of the base of the thumb were performed in 18 healthy infants (mean age ± SD, 13.8 ± 9.1 weeks; 44% female). Assuming an elliptical shape, the mean areas of the scaphoid and first metacarpal epiphysis measured 0.85 ± 0.19 and 0.44 ± 0.087 cm² , respectively. The mean areas of the trapezium and ossified first metacarpal as approximate rectangular shapes measured 0.23 ± 0.069 and 0.49 ± 0.16 cm² . A perimeter tracing was also used as an alternative area calculation. The mean trapezium area-to-scaphoid area ratio (0.28 ± 0.10) showed less variability compared to the first metacarpal epiphysis area-to-scaphoid area ratio (0.55 ± 0.20) or first metacarpal area-to-scaphoid area ratio (0.64 ± 0.31).

CONCLUSIONS

Our data suggest that US is well suited for the evaluation of the lateral carpus and base of the thumb in young infants. These data serve as a reference to which wrist and thumb abnormalities can be compared.

Wrist ultrasound examination - scanning technique and ultrasound anatomy. Part 2: Ventral wrist

Ultrasound imaging of the musculoskeletal system is an important element of the diagnostic and therapeutic protocol. Clinical decisions, including those regarding surgical procedures, are often based solely on ultrasound imaging. However, detailed knowledge on the anatomy and a correct scanning technique are crucial for an accurate diagnosis. Modern ultrasonographic equipment allows obtaining detailed anatomical images of muscle tendons, ligaments, nerves and vessels of the carpal area. Ventral wrist ultrasound is one of the most common diagnostic procedures in patients with suspected carpal tunnel syndrome. Ventral wrist evaluation is also often performed in patients with wrist pain of unclear etiology, rheumatic diseases, wrist injuries or symptoms of ulnar neuropathy. The aim of this paper is to present ultrasound images with corresponding anatomical schemes. The technique of ultrasound examination of the ventral wrist along with practical guidance to help obtain highly diagnostic images is also discussed. The present paper is the second part of an article devoted to ultrasound anatomy and wrist ultrasound technique – the part discussing the dorsal side of the wrist was published in the Journal of Ultrasonography, Vol. 15, No 61. The following anatomical structures should be visualized during an ultrasound examination of the ventral wrist, both in the carpal tunnel as well as proximally and distally to it: four flexor digitorum superficialis tendons, four flexor digitorum profundus tendons, flexor pollicis longus, flexor carpi radialis tendon, median nerve and flexor retinaculum; in the carpal tunnel as well as proximally and distally to it: the ulnar nerve, ulnar artery and veins; the tendon of the flexor carpi ulnaris muscle; carpal joints.