What Is the Diagnostic Accuracy of Flat-panel Cone-beam CT Arthrography for Diagnosis of Scapholunate Ligament Tears?

Is Midcarpal Arthroscopy for Suspected Scapholunate Pathology Associated With Greater Interobserver Agreement and More Frequent Offer of Surgery?

PURPOSE

This study compared the interobserver agreement of arthroscopic classification of suspected scapholunate interosseous ligament (SLIL) pathology with and without midcarpal arthroscopy to help inform diagnostic strategies. It also measured the association of midcarpal arthroscopy with recommendations for reconstructive surgery. The association of midcarpal arthroscopy with the type of surgery recommended was also studied.

METHODS

Fourteen consecutive videos of diagnostic radiocarpal and midcarpal wrist arthroscopy for suspected SLIL pathology were selected. An international survey-based experiment was conducted among upper extremity surgeons of the Science of Variation Group. Participants were randomized to view either radiocarpal arthroscopic videos or radiocarpal and midcarpal videos. Surgeons rated SLIL pathology according to the Geissler classification and recommended surgical or nonsurgical treatment. If surgical treatment was recommended, they indicated the type of procedure.

RESULTS

The interobserver agreement for the Geissler classification was slight/fair for observers who reviewed midcarpal and radiocarpal videos and for those who viewed radiocarpal videos only. Viewing midcarpal videos was associated with higher pathology grades, the recommendation for reconstructive surgery, and a preference for tenodesis over scapholunate ligament repair.

CONCLUSIONS

Diagnostic wrist arthroscopy for a wrist with normal radiological alignment has poor interobserver agreement.

CLINICAL RELEVANCE

The pursuit of a pathology that accounts for wrist symptoms in a nonspecific interview and examination and normal radiographs is understandable; however, the low reliability of the scapholunate pathology of diagnostic arthroscopy might be associated with more potential harm than benefit.

Contrast solution properties and scan parameters influence the apparent diffusivity of computed tomography contrast agents in articular cartilage

The inability to detect early degenerative changes to the articular cartilage surface that commonly precede bulk osteoarthritic degradation is an obstacle to early disease detection for research or clinical diagnosis. Leveraging a known artefact that blurs tissue boundaries in clinical arthrograms, contrast agent (CA) diffusivity can be derived from computed tomography arthrography (CTa) scans. We combined experimental and computational approaches to study protocol variations that may alter the CTa-derived apparent diffusivity. In experimental studies on bovine cartilage explants, we examined how CA dilution and transport direction (absorption versus desorption) influence the apparent diffusivity of untreated and enzymatically digested cartilage. Using multiphysics simulations, we examined mechanisms underlying experimental observations and the effects of image resolution, scan interval and early scan termination. The apparent diffusivity during absorption decreased with increasing CA concentration by an amount similar to the increase induced by tissue digestion. Models indicated that osmotically-induced fluid efflux strongly contributed to the concentration effect. Simulated changes to spatial resolution, scan spacing and total scan time all influenced the apparent diffusivity, indicating the importance of consistent protocols. With careful control of imaging protocols and interpretations guided by transport models, CTa-derived diffusivity offers promise as a biomarker for early degenerative changes.