Patient knowledge in anaesthesia: Psychometric development of the RAKQ-The Rotterdam anaesthesia Knowledge questionnaire.

The transition from in-person to digital preoperative patient education requires effective methods for evaluating patients' understanding of the perioperative process, risks, and instructions to ensure informed consent. A knowledge questionnaire covering different anaesthesia techniques and instructions could fulfil this need. We constructed a set of items covering common anaesthesia techniques requiring informed consent and developed the Rotterdam Anaesthesia Knowledge Questionnaire (RAKQ) using a structured approach and Item Response Theory. A team of anaesthetists and educational experts developed the initial set of 60 multiple-choice items, ensuring content and face validity. Next, based on exploratory factor analysis, we identified seven domains: General Anaesthesia-I (regarding what to expect), General Anaesthesia-II (regarding the risks), Spinal Anaesthesia, Epidural Anaesthesia, Regional Anaesthesia, Procedural sedation and analgesia, and Generic Items. This itemset was filled out by 577 patients in the Erasmus MC, Rotterdam, and Albert Schweitzer Hospital, Dordrecht, the Netherlands. Based on factor loadings (≥0.25) and considering clinical relevance this initial item set was reduced to 50 items, distributed over the seven domains. Each domain was processed to produce a separate questionnaire. Through an iterative process of item selection to ensure that the questionnaires met the criteria for Item Response Theory modelling, 40 items remained in the definitive set of seven questionnaires. Finally, we developed an Item Response Theory model for each questionnaire and evaluated its reliability. 1-PL and 2-PL models were chosen based on best model fit. No item misfit (S-χ2, p<0.001 = misfit) was detected in the final models. The newly developed RAKQ allows practitioners to assess their patients' knowledge before consultation to better address knowledge gaps during consultation. Moreover, they can decide whether the level of knowledge is sufficient to obtain digital informed consent without face-to-face education. Researchers can use the RAKQ to compare new methods of patient education with traditional methods.

Dynamic sonographic measurements at the carpal tunnel inlet: reliability and reference values in healthy wrists.

INTRODUCTION: Reliability and reference values are not well-established for most dynamic sonographic measurements of the median nerve (MN) and flexor tendons that may be used for diagnosing carpal tunnel syndrome (CTS). METHODS: Wrists of 20 healthy participants were imaged using ultrasound. Cines of the carpal tunnel inlet were acquired during hand motion. Based on shape and displacement measurements, intra- and interrater reliability and reference values were calculated. RESULTS: Intraclass correlation coefficients (ICCs) for measurements of the MN and most flexor tendons were ≥0.51 for shape parameters and ≥0.71 for displacement parameters. During motion, the MN flattened with ulnar movement, tendons became more circular, and flexor tendons of corresponding fingers moved toward each other. CONCLUSION: Shape and displacement measurements of the MN and most flexor tendons had reliability results ranging from moderate to excellent. The reference values may be useful for the diagnosis of CTS.

Assessment of transverse ultrasonographic parameters to optimize carpal tunnel syndrome diagnosis in a case-control study.

INTRODUCTION: Transverse ultrasound measurements of the median nerve (MN) for diagnosis of carpal tunnel syndrome (CTS) suffer from inconsistent findings within and between patients and healthy subjects. The objective of this study was to improve ultrasound assessment of CTS. METHODS: In a case-control study (51 patients, 25 controls) we evaluated the performance gained by: (1) correcting for ultrasound probe angulation; (2) including active parameters such as forceful gripping of the hand; and (3) including hand flexor tendon parameters. RESULTS: Correcting ultrasound probe angulation increased the correct classification rate by 4.5%; including forceful gripping resulted in increasing it by 2.8%; and including the hand flexor tendon resulted in an increase of 1.3%. CONCLUSIONS: The best predictive model combines correcting probe angulation with forceful gripping parameters and hand flexor tendon parameters. However, the clinically most practical model might use only probe angulation correction.

Ultrasonographic assessment of longitudinal median nerve and hand flexor tendon dynamics in carpal tunnel syndrome.

INTRODUCTION: Changes in subsynovial connective tissue (SSCT) in carpal tunnel syndrome (CTS) patients may result in altered dynamics; consequently, quantification of these dynamics might support objective diagnosis of CTS. METHODS: We measured and compared longitudinal excursion of the flexor digitorum superficialis and profundus tendons, the median nerve, and the SSCT between the most and least affected hands of 51 CTS patients during extension-to-fist motion. RESULTS: Median nerve and flexor digitorum superficialis tendon excursions in the most affected hands were smaller than in the least affected hands of the same patients, whereas the excursions of the flexor digitorum profundus were larger. Based on these excursions, logistic regression models classified between 67% and 86% of the hands correctly as having CTS. CONCLUSIONS: The altered hand dynamics in CTS patients may have implications for the pathophysiology and clinical evaluation of CTS, and ultrasound-based classification models may further support the diagnosis of CTS.

Ultrasonographic assessment of flexor tendon mobilization: effect of different protocols on tendon excursion.

BACKGROUND: Different mobilization protocols have been proposed for rehabilitation after hand flexor tendon repair to provide tendon excursion sufficient to prevent adhesions. Several cadaver studies have shown that the position of the neighboring fingers influences tendon excursions of the injured finger. We hypothesized that the positions of adjacent fingers influence the long finger flexor digitorum profundus tendon excursion, measured both absolutely and relative to the surrounding tissue of the tendon. METHODS: Long finger flexor digitorum profundus tendon excursions and surrounding tissue movement were measured in zone V in eleven healthy subjects during three different rehabilitation protocols and two experimental models: (1) an active four-finger mobilization protocol, (2) a passive four-finger mobilization protocol, (3) a modified Kleinert mobilization protocol, (4) an experimental modified Kleinert flexion mobilization model, and (5) an experimental modified Kleinert extension mobilization model. Tendon excursions were measured with use of a frame-to-frame analysis of high-resolution ultrasound images. RESULTS: The median absolute long finger flexor digitorum profundus tendon excursions were 23.4, 17.8, 10.0, 13.9, and 7.6 mm for the active four-finger mobilization protocol, the passive four-finger mobilization protocol, the modified Kleinert mobilization protocol, the experimental modified Kleinert flexion mobilization model, and the experimental modified Kleinert extension mobilization model, respectively, and these differences were all significant (p ≤ 0.041). The corresponding relative flexor digitorum profundus tendon excursions were 11.2, 8.5, 7.2, 10.4, and 5.6 mm. Active four-finger mobilization protocol excursions were significantly (p = 0.013) greater than passive four-finger mobilization protocol excursions but were not significantly greater than experimental modified Kleinert flexion mobilization model excursions (p =0.213). CONCLUSIONS: The present study demonstrated large and significant differences among the different rehabilitation protocols and experimental models in terms of absolute and relative tendon displacement. More importantly, the present study clearly demonstrated the influence of the position of the adjacent fingers on the flexor tendon displacement of the finger that is mobilized.

Ultrasonographic assessment of long finger tendon excursion in zone v during passive and active tendon gliding exercises.

PURPOSE: Cadaver and in vivo studies report variable results for tendon excursion during active and passive hand movements. The purpose of this study was to measure long finger flexor digitorum profundus (FDP) tendon excursion during active and passive movement using high-resolution ultrasound images. METHODS: The FDP tendon excursion was measured at the wrist level in 10 healthy subjects during full tip-to-palm active and passive flexion of the fingers. Passive movement was performed 2 ways: (1) straight to full fist: passive flexion starting at the metacarpophalangeal joint, followed by proximal interphalangeal and distal interphalangeal joint flexion; and (2) hook to full fist: passive flexion starting at the distal interphalangeal joint, followed by proximal interphalangeal and metacarpophalangeal joint flexion. Tendon excursion was measured using an in-house-developed, frame-to-frame analysis of high-resolution ultrasound images. RESULTS: Median FDP excursion was 24.3 mm, 14.0 mm, and 13.6 mm for active fist, straight to full fist, and hook to full fist movements, respectively. Tendon excursions during active movements was significantly larger than excursions during passive movements (p = .005). The adjusted median tendon excursion was 12.7 mm/100 degrees , 7.5 mm/100 degrees , and 7.4 mm/100 degrees for active fist, straight to full fist, and hook to full fist movements, respectively. Adjusted tendon excursions during active movement were significantly larger than those achieved during passive straight to full fist movement). Adjusted tendon excursions during straight to full fist movements were significantly larger than those achieved during passive hook to full fist movement. CONCLUSIONS: Active motion produced 74% and 79% increases in excursions compared to both passive motions in healthy controls. The study results can serve as a reference for evaluating excursions in patients with tendon pathology, including those who have had tendon repair and reconstruction.

Development and validation of ultrasound speckle tracking to quantify tendon displacement.

Ultrasound can be used to study tendon movement. However, measurement of tendon movement is mostly based on manual tracking of anatomical landmarks such as the musculo-tendinous junction, limiting the applicability to a small number of muscle-tendon units. The aim of this study was to quantify tendon displacement without anatomical landmarks using a speckle tracking algorithm optimized for tendons in long B-mode image sequences. A dedicated two-dimensional multi-kernel block-matching scheme with subpixel motion estimation was devised to handle large displacements over long sequences. The accuracy of the tracking on porcine tendons was evaluated during different displacements and velocities. Subsequently, the accuracy of tracking the flexor digitorum superficialis (FDS) of a human cadaver hand was evaluated. Finally, the in-vivo accuracy of the tendon tracking was determined by measuring the movement of the FDS at the wrist level. For the porcine experiment and the human cadaver arm experiment tracking errors were, on average, 0.08 and 0.05mm, respectively (1.3% and 1.0%). For the in-vivo experiment the tracking error was, on average, 0.3mm (1.6%). This study demonstrated that our dedicated speckle tracking can quantify tendon displacement at different physiological velocities without anatomical landmarks with high accuracy. The technique allows tracking over large displacements and in a wider range of tendons than by using anatomical landmarks.