Purpose Attempts to quantify hand movements of surgeons during arthroscopic surgery faced limited progress beyond motion analysis of hands and/or instruments. Surrogate markers such as procedure time have been used. The dimensionless squared jerk (DSJ) is a measure of deliberate hand movements. This study tests the ability of DSJ to differentiate novice and expert surgeons (construct validity) whilst performing simulated arthroscopic shoulder surgical tasks. Methods Six residents (novice group) and six consultants (expert group) participated in this study. Participants performed three validated tasks sequentially under the same experimental setup (one performance). Each participant had ten performances assessed. Hand movements were recorded with optical tracking system. The DSJ, time taken, total path length, multiple measures of acceleration, and number of movements were recorded. Results There were significant differences between novices and experts when assessed using time, number of movements with average and minimal acceleration threshold, and DSJ. No significant differences were observed in maximum acceleration, total path length, and number of movements with 10m/s2 acceleration threshold. Conclusion DSJ is an objective parameter that can differentiate novice and expert surgeons' simulated arthroscopic performances. We propose DSJ as an adjunct to more conventional parameters for arthroscopic surgery skills assessment.

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BackgroundWe have developed a new arthroscope with a field of view of 150°. This arthroscope requires less motion to maneuver and exhibits reduced optical error. It also improves how novices learn arthroscopy. We hypothesized that the surgical performance with this arthroscope is superior to that with a conventional arthroscope. This study tested the hypothesis by using motion analysis and a new validated parameter, “dimensionless squared jerk” (DSJ).MethodsWe compared the surgical performance between the use of the wide-angle arthroscope and that of the conventional arthroscope among 14 novice orthopedic residents who performed 3 standardized tasks 3 times with each arthroscope. The tasks simulated the surgical skills in arthroscopic rotator cuff repair. The arthroscope motion was analyzed using an optical tracking system. The differences in performance parameters, such as the time taken to complete the tasks, average acceleration of the hands (m/s2), number of movements, and total path length (m) including DSJ between the 2 arthroscopes were investigated using paired t-tests.ResultsAll estimated values for the tasks using the 150° arthroscope were lower than those for the tasks using the 105° arthroscope. Statistically significant differences in performance between the 2 arthroscopes were observed only for DSJ (p = 0.014) and average acceleration (p = 0.039).ConclusionsDSJ and average acceleration are reliable parameters for representing hand-eye coordination. The surgical performance of novice arthroscopists was better with the new wide-angle arthroscope than with the conventional arthroscope.

Background:Multiple reconstruction techniques have been described in the management of chronic scapholunate (SL) instability, either based on the capsulodesis or tenodesis principle. It is uncertain which surgical method produces the best patient outcomes. We describe results of a technique using palmaris longus (PL) tendon for surgical reconstruction of the SL ligament and provide functional outcomes scores.Materials and Methods:We surgically reconstructed the SL ligament using a PL tendon graft secured with Mitek® bone anchors. Surgical technique with photographs is provided in the main text. Functional outcomes were measured using the disabilities of the arm, shoulder, and hand and Mayo wrist scores. Patient satisfaction was assessed using a simple measure.Results:Eleven patients attended mid-term followup (mean 45.8 months post-surgery) and had functional outcomes and satisfaction of this procedure that compared favorably to case series that used tenodesis for chronic SL ligament injuries. Almost all patients (n = 10) were able to return to regular employment. The majority of patients (n = 10) were satisfied with their primary reconstruction procedure.Conclusion:This technique avoids the use of drill holes to weave tendon through bone, uses an easy to access graft, and exploits the superior pullout strength of anchors while offering satisfactory functional outcomes that are comparable to alternative tenodesis techniques.