Sonographic evaluation of scapholunate ligament: value of tissue harmonic imaging

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.

[Establishing a standardized diagnostic Procedure for sonographic Imaging and Evaluation of the scapholunate Ligament]

BACKGROUND

Ultrasound has not yet been established in the diagnostic workup of scapholunate ligament lesions. We aimed to develop a standardised examination procedure to visualise and evaluate the SL ligament.

PATIENTS AND METHODS

Forty patients (70 hands) were examined prospectively with ultrasonography and the results were compared with arthroscopy and MRI findings. We studied the visibility of the SL ligament and the SL distance on side-to-side comparison and performed a method comparison between MRI/arthroscopy and ultrasound, testing for distinction and accordance. Cut-off values for the SL distance indicating a lesion were determined and all parameters were used for developing a score.

RESULTS

An intact ligament appears as a hyperechogenic, fibrillary structure and shows discontinuity or a hypoechogenic space when injured. An intact ligament was visible dorsally in 89.6 % and palmarly in 83.3 %. The SL distance for an intact ligament was 5/2/5.1 mm for the dorsal/middle/palmar aspect (range 3.2-6.7/0.9-4/3.1-7.8 mm) and 6.4/3/6.3 mm (range 5-9.4/2-6.2/4-9.3 mm) for a lesion. The difference between the right and left hand with an intact ligament was a maximum of 2.1/1.1/1.8 mm, an average of 0.4/0.2/0.2 mm; in case of an injury, the maximum difference was 1.2/0.9/1.1 mm. Distance values for radial and ulnar deviation were physiological but partly unpredictable. The cut-off values determined for a lesion are 5.05 mm for the dorsal aspect (sensitivity/specificity 0.95/0.60), 1.95 mm for the middle (1/0.62) and 6.15 mm for the palmar aspect (0.55/0.85). The created sonographic SL ligament score has a high AUC (area under the curve) of 0.93, a sensitivity of 85 % and a specificity of 90 %.

CONCLUSION

The parameters, especially when combined to a score, allow to state whether the SL ligament is intact or not. Ultrasound can, therefore, be recommended as a diagnostic and screening method for an SL ligament lesion und should be used as a routine tool. The criteria must be checked from a perspective with high case numbers.

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.

The Quantitative Anatomy of the Dorsal Scapholunate Interosseous Ligament

BACKGROUND

The anatomy of the scapholunate interosseous ligament (SLIL) has been described qualitatively in great detail, with recognition of the dorsal component's importance for carpal stability. The purpose of this study was to define the quantitative anatomy of the dorsal SLIL and to assess the use of high-frequency ultrasound to image the dorsal SLIL.

METHODS

We used high-frequency ultrasound imaging to evaluate 40 wrists in 20 volunteers and recorded the radial-ulnar (length) and dorsal-volar (thickness) dimensions of the dorsal SLIL and the dimensions of the scapholunate interval. We assessed the use of high-frequency ultrasound by comparing the length and thickness of the dorsal SLIL on ultrasound evaluation and open dissection of 12 cadaveric wrists. Student's t test was used to assess the relationship between measurements obtained on cadaver ultrasound and open dissection.

RESULTS

In the volunteer wrists, the mean dorsal SLIL length was 7.5 ± 1.4 mm and thickness was 1.8 ± 0.4 mm; the mean scapholunate interval was 5.0 mm dorsally and 2.5 mm centrally. In the cadaver wrists, there was no difference in dorsal SLIL length or thickness between ultrasound and open dissection.

CONCLUSIONS

The dorsal SLIL is approximately 7.5 mm long and 1.8 mm thick. These parameters may be useful in treatment of SLIL injuries to restore the native anatomy. High-frequency ultrasound is a useful imaging technique to assess the dorsal SLIL, although further study is needed to assess the use of high-frequency ultrasound in detection of SLIL pathology.

Imaging of Wrist Injuries: A Standardized US Examination in Daily Practice

The keys to successful ultrasonography (US) of the wrist include knowledge of the relevant anatomy and understanding the biomechanical aspects. A wide spectrum of pathological findings including bone fractures (scaphoid, triquetrum) and ligament lesions (dorsal intercarpal and radiocarpal ligaments, scapholunate ligament) can be caused by an identical traumatic mechanism determined on the basis of the position of wrist at the time of injury.

In the setting of wrist trauma, an early diagnosis can minimize the potential for inappropriate or delayed treatment. We describe a practical radiological approach by using a standardized imaging protocol: standard radiographs (four views) associated with an US examination focused on seven landmarks. If there is discordance between clinical and radiological features or if the diagnosis of a disruption of the scapholunate ligament remains uncertain, additional cross-sectional imaging (MRI or CT arthrogaphy) should be performed.

Ultrasound of the hand and wrist

There have been immense technical innovations and broadened clinical applications of ultrasound in the musculoskeletal system over the past 20 years. Specifically with regard to the hand and wrist, the advent of higher resolution transducers and postprocessing software applications have resulted in overall enhanced visualization of soft tissue structures (tendons/ligaments) as well as surface osseous lesions such as subclinical erosions in rheumatoid arthritis. Quantitative ultrasound, using either power Doppler or contrast-enhanced imaging, has become a central outcomes measure used to evaluate and document patient response to treatment in inflammatory arthropathies such as rheumatoid arthritis. This review will summarize the current state of clinical applications of ultrasound in the evaluation of the hand and wrist, with a summary of technical advances and specific applications in rheumatologic conditions.This review was exempt from institutional review board approval.

Comprehensive musculoskeletal sonographic evaluation of the hand and wrist

Sonography is widely used for evaluation of hand and wrist lesions. The easy accessibility, cost-effectiveness, and good diagnostic accuracy of sonography coupled with the numerous benefits of real-time imaging make it desirable. The aim of this article is to describe the typical sonographic appearances of lesions in the hand and wrist that are encountered frequently in routine clinical practice, such as inflammatory arthropathies, tumors, traumatic injuries, foreign bodies, and nerve entrapment syndromes. Relevant anatomy, scanning methods, and recent developments in musculoskeletal sonography are also discussed.

Sonography and sonoarthrography of the scapholunate and lunotriquetral ligaments and triangular fibrocartilage disk: initial experience and correlation with arthrography and magnetic resonance arthrography

OBJECTIVE

The purpose of this study was to determine the utility of sonography and sonoarthrography in evaluation of dorsal bands of the scapholunate ligament (SLL), lunotriquetral ligament (LTL), and triangular fibrocartilage (TFC) disk in correlation with arthrography and magnetic resonance arthrography (MRA).

METHODS

High-resolution sonography of the SLL, LTL, and TFC disk was performed on symptomatic wrists in 16 patients referred by a hand surgeon for MRA of the symptomatic wrists. All patients then underwent arthrography and an MRA study of the same wrist. After MRA, sonography was repeated. The imaging findings of these different techniques were then compared. Four patients (25%) underwent surgery of their wrists. In these 4 patients, the surgical and imaging findings were correlated.

RESULTS

For the SLL, the results were concordant for all imaging modalities in 15 patients (93.75%) and partially concordant in 1 (6.25%). For the LTL, the results were concordant for all imaging modalities in 12 patients (75%), partially concordant in 3 (18.75%), and discordant in 1 (6.25%). For the TFC disk, the results were concordant for all imaging modalities in 13 patients (81.25%), partially concordant in 2 (12.5%), and discordant in 1 (6.25%). The arthroscopic and imaging findings were concordant for 3 SLLs, 3 LTLs, and 3 TFC disks.

CONCLUSIONS

Our preliminary results are encouraging. Sonography may be used at least as a screening imaging modality in evaluation of the SLL and TFC disk. Sonoarthrography improves evaluation of the LTL.