No abstract

BackgroundCarpal instability is defined as a condition where wrist motion and/or loading creates mechanical dysfunction, resulting in weakness, pain and decreased function. When conventional methods do not identify the instability patterns, yet clinical signs of instability exist, the diagnosis of dynamic instability is often suggested to describe carpal derangement manifested only during the wrist’s active motion or stress. We addressed the question: can advanced MRI techniques provide quantitative means to evaluate dynamic carpal instability and supplement standard static MRI acquisition? Our objectives were to (i) develop a real-time, three-dimensional MRI method to image the carpal joints during their active, uninterrupted motion; and (ii) demonstrate feasibility of the method for assessing metrics relevant to dynamic carpal instability, thus overcoming limitations of standard MRI.MethodsTwenty wrists (bilateral wrists of ten healthy participants) were scanned during radial-ulnar deviation and clenched-fist maneuvers. Images resulting from two real-time MRI pulse sequences, four sparse data-acquisition schemes, and three constrained image reconstruction techniques were compared. Image quality was assessed via blinded scoring by three radiologists and quantitative imaging metrics.ResultsReal-time MRI data-acquisition employing sparse radial sampling with a gradient-recalled-echo acquisition and constrained iterative reconstruction appeared to provide a practical tradeoff between imaging speed (temporal resolution up to 135 ms per slice) and image quality. The method effectively reduced streaking artifacts arising from data undersampling and enabled the derivation of quantitative measures pertinent to evaluating dynamic carpal instability.ConclusionThis study demonstrates that real-time, three-dimensional MRI of the moving wrist is feasible and may be useful for the evaluation of dynamic carpal instability.

No abstract

Free vascularised fibular grafting is a successful form of treatment for large bony defects. These results suggest that the use of modern techniques of fixation does not affect the risk of nonunion when compared with traditional forms of fixation, and smoking increases the risk of nonunion following this procedure. Cite this article: Bone Joint J 2017;99-B:134-8.

Purpose In an attempt to restore natural carpal kinematics more closely, boneligament-bone (BLB) grafts have been described for treating scapholunate (SL) injury. In this article we report the long-term results of capitohamate BLB autograft for the treatment of SL dissociation. Methods The medical records of patients treated with capitohamate BLB grafts for SL dissociation were retrospectively reviewed. Twenty-three patients were available for evaluation. Patients were sent a Disabilities of the Arm, Shoulder, and Hand (DASH) and a Patient-Rated Wrist Evaluation (PRWE) questionnaire and returned for exam. Thirteen patients returned the questionnaire, and 12 wrists were examined. Range of motion, grip strength, pain, complications, return to work, and radiographic parameters were documented. Results The average length of follow-up evaluation was 9.2 years. The average SL gap was 4.5 mm preoperatively and 3.6 mm at final follow-up. The average SL angle was 70 degrees preoperatively and 73 degrees at final follow-up. There was no statistically significant difference in preoperative versus postoperative flexion, extension, radial deviation, ulnar deviation, or grip strength. The average postoperative visual analog scale (VAS) score was 1.25 at rest and 3.58 with activity. The average Mayo Wrist Score was 66.8 preoperatively and 70.9 postoperatively (p ¼ 0.158). The average postoperative PRWE was 20.5, and average postoperative DASH was 15.1. At final follow-up, four patients had no radiographic evidence of arthritis. Two patients had evidence of earlystage radiocarpal arthritis, four had evidence of midcarpal arthritis, and two had radiographic evidence of mild scaphotrapeziotrapezoid arthritis. One patient required a salvage procedure with four-corner fusion. Discussion BLB reconstruction can be used to treat SL instability. At final follow-up, the majority of patients did not worsen clinically or functionally or require secondary salvage procedures; however, radiologic progression of arthritis was not prevented. These outcomes are comparable to midterm results of other SL reconstructive options; thus, we have abandoned this technique for other less technically demanding procedures.