Intraobserver and interobserver variability in diagnosing scapholunate dissociation by cineradiography

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.

The Optimal Location to Measure Scapholunate Diastasis on Screening Radiographs

BACKGROUND

Lack of a universally accepted location and normal value limits the utility of measuring scapholunate diastasis. The primary purpose of this study was to define the optimal location to measure the scapholunate gap throughout sequential ligament transections. Secondary purposes were to compare plain radiographs with fluoroscopy and to evaluate interrater reliability in measuring scapholunate diastasis.

METHODS

Five cadaver forearms were imaged with intact carpal ligaments and after sequentially transecting the scapholunate, radioscaphocapitate, and scaphotrapezium-trapezoid ligaments. Plain radiographs and static fluoroscopic images were obtained with wrists in neutral and 30° ulnar deviation for each stage. Multiple reviewers performed measurements of the scapholunate interval at 3 separate locations. Mean distances were calculated and pairwise comparisons between groups were made. Intraclass correlation was calculated to determine interrater reliability.

RESULTS

Overall, measurements made in the middle of the scapholunate joint had the smallest margins of error for all imaging modalities, ligament disruptions, and wrist positions. For normal wrists, the mean scapholunate measurements were all less than 2.0 mm at the middle of the joint, regardless of imaging modality or wrist position. Fluoroscopy detected significance between more stages of instability than plain radiographs at the middle of the joint.

CONCLUSIONS

Measurements in the middle of the scapholunate joint in neutral and 30° of ulnar deviation under fluoroscopic imaging best capture all stages of ligamentous disruptions. Measurements less than 2.0 mm at the middle of the scapholunate interval may be considered within normal range.

Wrist cineradiography: a protocol for diagnosing carpal instability

Carpal instability is often related to ruptured or lax carpal ligaments. Wrist cineradiography has been shown to be a good modality for diagnosing carpal instability. To create uniformity in obtaining and assessing wrist cineradiography, a wrist cineradiography protocol is desirable. This protocol will focus on wrist cineradiography for diagnosing carpal instabilities. It describes the pathologic motions of the carpus and correlates these with a clinical diagnosis.

LEVEL OF EVIDENCE

III.

Scapholunate dissociation; diagnostics made easy

Scapholunate dissociation (SLD) is a form of carpal instability, caused by rupture of the scapholunate ligament (SLL) the secondary stabiliser of the scapholunate (SL) compartment. SLD can cause osteoarthritis of the wrist. Recently a study was published that shows cineradiography to be an excellent radiological imaging technique for diagnosing SLD at a tertiary centre for hand and wrist surgery [1]. As the quality of these results can be influenced by the expertise of the operator and observer of the cineradiographic studies, the aim of this study was to determine if these results were reproducible at a secondary centre for hand and wrist surgery with less expertise in wrist cineradiography. All cineradiographic studies carried out during a 10-year period were obtained. All patients who underwent the gold standard procedure (arthroscopy/arthrotomy) after cineradiography were included, a total of 50 patients. The diagnostic accuracy of detecting SLD by both cineradiography and conventional radiography was calculated. Cineradiography had a high diagnostic accuracy, while the accuracy for conventional radiography was average. When all wrists with an SL distance ≥3mm were excluded (static SLD), diagnostic accuracy for conventional radiography dropped even lower, while accuracy for cineradiography remained high. These results are comparable with published accuracy rates and show that cineradiography has a high diagnostic value for detecting SLD and do not seem to be influenced by the operator or observer of the cineradiographic studies.

Scapholunate and perilunate injuries in the athlete

PURPOSE OF THE REVIEW

Scapholunate and perilunate injuries can be difficult to diagnose and treat in the athlete. In this review article, we present the mechanism of injury, evaluation, management, and outcomes of treatment for these injuries.

RECENT FINDINGS

Acute repair of dynamic scapholunate ligament injuries remains the gold standard, but judicious use of a wrist splint can be considered for the elite athlete who is in season. The treatment of static scapholunate ligament injury remains controversial. Newer SL reconstructive techniques that aim to restore scapholunate function without compromising wrist mobility as much as tenodesis procedures show promise in athlete patients. Acute injuries to the scapholunate ligament are best treated aggressively in order to prevent the sequelae of wrist arthritis associated with long-standing ligamentous injury. Acute repair is favored. Reconstructive surgical procedures to manage chronic scapholunate injury remain inferior to acute repair. The treatment of lunotriquetral ligament injuries is not well defined.

Imaging in carpal instability

Carpal instability is a complex and heterogeneous clinical condition. Management requires accurate identification of structural injury with an understanding of the resultant movement (kinematic) and load transfer (kinetic) failure. Static imaging techniques, such as plain film radiography, stress views, ultrasound, magnetic resonance, MR arthrography and computerized tomography arthrography, may accurately depict major wrist ligamentous injury. Dynamic ultrasound and videofluoroscopy may demonstrate dynamic instability and kinematic dysfunction. There is a growing evidence base for the diagnostic accuracy of these techniques in detecting intrinsic ligament tears, but there are limitations. Evidence of their efficacy and relevance in detection of non-dissociative carpal instability and extrinsic ligament tears is weak. Further research into the accuracy of existing imaging modalities is still required. Novel techniques, including four-dimensional computerized tomography and magnetic resonance, can evaluate both cross-sectional and functional carpal anatomy. This is a narrative review of level-III studies evaluating the role of imaging in carpal instability.

Comparisons of three radiographic views in assessing for scapholunate instability

BACKGROUND

Multiple wrist x-ray images have been described to assess for scapholunate (SL) instability. Some views may be redundant. The purpose of this study was to compare three plain x-ray views in identifying a traumatic diastasis of the SL interval.

METHODS

Nineteen patients (19 wrists) with a positive scaphoid shift test and surgically confirmed SL ligament damage were identified. There were 15 males and 4 females with a mean age of 39 years. Pre-operative x-rays were reviewed, including posteroanterior (PA) neutral and PA ulnar deviation views of the injured wrist, and PA clenched fist views of the injured and uninjured wrists. Dynamic SL instability was defined by an SL mid-interval gap of <3 mm and static SL instability by a gap of ≥3 mm in the PA neutral views. The mid-interval measurements were compared between x-ray images.

RESULTS

There were 10 dynamic and 9 static SL instability cases. The PA ulnar deviation and the PA clenched fist views showed significantly greater SL gaps in comparison to the PA neutral views in dynamic but not static SL instability cases. In both categories of instability, there was no significant difference in the SL gaps between the two stress images. The PA clenched fist view of the uninjured wrist revealed SL gapping of >3 mm in 50% of patients but with generally greater gapping in the clenched fist view of the injured wrist.

CONCLUSIONS

The PA ulnar deviation and clenched fist stress views were equally effective in showing a dynamic SL diastasis following wrist injury. Neither view was more effective than a neutral PA view in diagnosing static SL instability.