Wrist angle measurements in predicting the presence of a displaced scaphoid fracture

Artificial intelligence for automated detection and measurements of carpal instability signs on conventional radiographs

OBJECTIVES

To develop and validate an artificial intelligence (AI) system for measuring and detecting signs of carpal instability on conventional radiographs.

MATERIALS AND METHODS

Two case-control datasets of hand and wrist radiographs were retrospectively acquired at three hospitals (hospitals A, B, and C). Dataset 1 (2178 radiographs from 1993 patients, hospitals A and B, 2018-2019) was used for developing an AI system for measuring scapholunate (SL) joint distances, SL and capitolunate (CL) angles, and carpal arc interruptions. Dataset 2 (481 radiographs from 217 patients, hospital C, 2017-2021) was used for testing, and with a subsample (174 radiographs from 87 patients), an observer study was conducted to compare its performance to five clinicians. Evaluation metrics included mean absolute error (MAE), sensitivity, and specificity.

RESULTS

Dataset 2 included 258 SL distances, 189 SL angles, 191 CL angles, and 217 carpal arc labels obtained from 217 patients (mean age, 51 years ± 23 [standard deviation]; 133 women). The MAE in measuring SL distances, SL angles, and CL angles was respectively 0.65 mm (95%CI: 0.59, 0.72), 7.9 degrees (95%CI: 7.0, 8.9), and 5.9 degrees (95%CI: 5.2, 6.6). The sensitivity and specificity for detecting arc interruptions were 83% (95%CI: 74, 91) and 64% (95%CI: 56, 71). The measurements were largely comparable to those of the clinicians, while arc interruption detections were more accurate than those of most clinicians.

CONCLUSION

This study demonstrates that a newly developed automated AI system accurately measures and detects signs of carpal instability on conventional radiographs.

CLINICAL RELEVANCE STATEMENT

This system has the potential to improve detections of carpal arc interruptions and could be a promising tool for supporting clinicians in detecting carpal instability.

Long-term clinical and radiological results after scaphoid non-union treatment: a retrospective study about 60 cases

PURPOSE

Scaphoid non-union treatment remains nonconsensual and is based on vascularized or non-vascularized bone grafting. This study aimed to evaluate with a long follow-up the functional, clinical, and radiological outcomes, reported complications and reoperations and studied non-union treatment prognostic factors.

METHODS

Patients who had undergone bone graft surgery for scaphoid non-union were retrospectively reviewed. The evaluated outcomes were pain, qDASH, PRWE and MWS scores, active range of motion, grip strength, union rate, scapholunate angle, carpal height, and presence of arthrosis. Complications and reinterventions were also reported.

RESULTS

This study included 60 scaphoid non-union treatments with a mean follow-up of 7.7 (1.5-20.3) years. Twenty (33.3%) non-unions were located at the proximal pole, including 6 (10%) with preoperative avascular necrosis (AVN). Union occurred in 51 patients (85%). The functional, clinical, and radiological results were good. The complication rate was 21.3% and the reintervention rate was 16.7%. Subgroup union rate analysis found no difference if the non-union is localized in the proximal pole or if there is AVN.

CONCLUSION

With a representative sample of the population and a long follow-up, we have found a good union rate, clinical and functional results regardless of the treatment method chosen. Scaphoid non-union treatment is still controversial and more studies are needed to accurate indications of each graft according to the patient and non-union characteristics.

LEVEL OF EVIDENCE IV

Retrospective cohort study.