OBJECTIVE The purpose of this study was to assess the safety of sonographically guided percutaneous finger and thumb first annular (A1) pulley releases performed using needle and hook knife techniques in an unembalmed cadaveric model. METHODS A single operator completed 50 (40 fingers and 10 thumbs) sonographically guided percutaneous A1 pulley releases in unembalmed cadavers using previously...

Dear Editor, We appreciate the careful analysis Demer has provided of our recent paper describing the first measurements of the mechanical properties of pulley bands. We wish to initially delineate the areas of agreement, before responding to the criticism of Demer in detail. The extraocular muscle (EOM) bellies do not displace sideways in eye movements out of the plane of the muscle, this is a...

Trigger finger is a common condition, occurs primarily at the A1 pulley and tenosynovitis is the usual cause. However, although rare, triggering of the flexor tendon can occur in other areas. We present previously unreported condition in adult: triggering at the distal end of A2 pulley, which was caused by nodular thickening of the flexor digitorium profondus tendon with degeneration. A 79-year...

PURPOSE Fibroelastic pulleys function like the trochlea to fix the position and pulling direction of the recti extraocular muscles within the orbit. This study characterized the fine structure of the human medial rectus muscle pulley. METHODS Human medial rectus muscle pulley tissue was dissected at autopsy, immersed in aldehyde fixative solution, and processed for and examined with light and...

INTRODUCTION Connective tissue bands connect the horizontal rectus muscles at the level of the posterior pole to the orbital wall. These bands, referred to as pulley bands or faisseaux tendineux, purportedly act like springs to keep the rectus muscle bellies in place during eye movement out of the plane of the muscle. We examined the mechanical properties of these bands in human specimens obtai...

The friction coefficient between a guide and a tape sample is determined experimentally as a function of nominal tension, speed and guide radius. A comparative study between metal particulate and metal evaporated tape is performed. The tape/guide contact pressure correlated to the experimental results. Tape temperature measurements are compared with the experimentally obtained friction coeffici...

Due to a lack of appropriate image resolution, most ultrasound scanners are unable to sensitively discern the pulley tissues. To extensively investigate the properties of the A1 pulley system and the surrounding tissues for assessing trigger finger, a 30 MHz ultrasound system was implemented to perform in vitro experiments using the hypodermis, A1 pulley, and superficial digital flexor tendon (...

PURPOSE. To evaluate the outcome of percutaneous release of the A1 pulley in 40 cadaveric fingers using a modified Kirschner wire. METHODS. A 2.5-mm-diameter Kirschner wire measuring >12 cm in length was used. One end of the wire was sharpened into a 'J' shape using a grinder. The J-shaped tip featured a blunt, elongated lower tip, a sharp J-shaped curve, and a blunt upper tip. Completeness of ...

Anatomical landmark of A1 pulley is important especially in minimal invasive surgery. The lengths and landmarks of A1 pulleys were evaluated in 510 preserved cadaver digits. The cadavers were 25 females and 26 males aged at the time of death ranged from 48 to 89 years. Measurements of A1 pulley lengths were made and used to predict the landmarks of the proximal pulley margins, which are related...

PURPOSE Percutaneous release of the A1 pulley has been used for treatment of trigger fingers with success. However, lack of direct visualization raises concerns about the completeness of the release and about potential injury to the tendons or neurovascular structures. The purpose of this study was to assess the efficacy and safety of percutaneous release of the A1 pulley in a cadaveric model u...