The Sonographic Squeeze Test: Assessing the Reliability of the Dorsal Scapholunate Ligament

Feasibility of ultrasound-based measurement of dorsal scaphoid displacement: A 3D-model study

The present study aimed to develop a reliable dynamic measurement technique, which can be used directly in the outpatient setting, based on dorsal subluxation of the scaphoid on scaphoid shift test. This study was designed to evaluate feasibility and to quantify dorsal subluxation of the scaphoid in relation to the lunate. Based on a scaphoid shift test under ultrasonography, a standardized 3D test model was developed to measure subluxation. Sagittal subluxation ranged between 0 and 6 mm, as checked on the implemented scale. Four hand surgeons trained in ultrasonography (experience level II-V) performed blinded measurements (total of 52, n = 13 per investigator) with a standardized measurement protocol. Dorsal subluxation of the scaphoid was measured in relation to the lunate. Interobserver reliability on intraclass correlation coefficient (ICC) was excellent, at 0.97 (95% confidence interval, 0.930-0.992). Mean overall absolute measurement error was 0.27 mm ± 0.21. Dorsal subluxation of the scaphoid can thus be accurately measured on ultrasound with excellent interobserver reliability, quantifying and improving clinical assessment of scapholunate instability.

Post-traumatic Scapholunate Advanced Collapse of the Wrist: A Case Report

Objective

The purpose of this report is to describe a patient with scapholunate advanced collapse (SLAC) of the wrist.

Clinical Features

A 38-year-old man presented to a chiropractic teaching clinic with right wrist pain after falling off of the tailgate of a truck 7 years prior. The mechanism of injury was a fall on an outstretched hand. Ultrasonography and radiography were performed, which demonstrated abnormal lunate kinematics and scapholunate interval diastasis associated with a clenched-fist maneuver. These findings were consistent with SLAC.

Intervention and Outcome

Following the diagnosis of SLAC, the wrist was splinted. Conservative care consisting of physical therapy included paraffin dips, therapeutic ultrasound, and stretching. The patient received only minimal alleviation of pain, and a surgical consultation was obtained. The patient elected surgical intervention, utilizing the proximal row carpectomy procedure.

Conclusion

This case demonstrates a patient with chronic wrist pain, with progression to carpal instability, which ultimately manifested as SLAC. We demonstrate, utilizing multiple imaging modalities, both preoperative and postoperative findings. To our knowledge, this is the first case to describe the use of diagnostic ultrasonography in the evaluation of the proximal row carpectomy procedure.