OBJECTIVE Sharp division of the A1 pulley is a time-honored technique for the treatment of flexor tendon entrapment; however, this procedure is not without complications. The anatomy of the A1 pulley system has been carefully investigated. Knowledge of superficial anatomic landmarks can assist with demarcating the distal edge of the A1 pulley and prevent damage to the critical A2 pulley. METH...

BACKGROUND Pulleys have been reported as the functional origins of the rectus extraocular muscles (EOMs). However, biomechanical significance of pulleys on binocular vision has not been reported. METHODS Three eye movement models, i.e., non-pulley model, passive-pulley model, and active-pulley model, are used to simulate the horizontal movement of the eyes from the primary position to the lef...

BACKGROUND The integrity of the flexor tendon pulley apparatus is crucial for unimpaired function of the digits. Although secondary reconstruction is an established procedure in multi-pulley injuries, acute reconstruction of isolated, closed pulley ruptures is a rare occurrence. There are 3 factors influencing the functional outcome of a reconstruction: gapping distance between tendon and bone ...

PURPOSE The purpose of this study was to investigate the effect of partial excision of the A2 pulley on the gliding resistance and the strength of the residual pulleys in a human in vitro model with or without tendon repair. METHODS We used 32 cadaveric human fingers from 11 cadavers. The A2 pulley was excised successively 25%, 50%, and 75%, cutting either from the distal toward the proximal ...

BACKGROUND Lesions of the biceps pulley and instability of the long head of the biceps tendon are common diagnoses in patients with anterior shoulder pain. PURPOSE To analyze the pathoanatomy of the biceps reflection pulley ("pulley") in consecutive patients undergoing shoulder arthroscopy. STUDY DESIGN Cohort study (prevalence); Level of evidence, 2. METHODS Prospective data were collect...

Light microscopy, electron microscopy and morphometry revealed structural details and allowed generation of a three-dimensional reconstruction of the pulley and muscle-pulley interface of extraocular muscle. The inferior rectus orbital layer was bifurcate in shape and extended anterior to the pulley. The putative pulley structure itself was asymmetric; loosely attached at the orbital aspect it ...

After a pulley rupture, most climbers regain the full function of their previously uninjured fingers. However, in some cases of pulley rupture, a persistent inflammation of the tendon sheath is observed. In this study, 16 cadaver fingers were loaded until pulley rupture and then studied for the rupturing mechanism. In addition, two patients with this pathology were investigated using ultrasound...

PURPOSE This study was undertaken to investigate evidence for a connective tissue pulley constraining the path of the inferior oblique (IO) muscle. METHODS From magnetic resonance images, the cross-sectional area, path, and orbital relationships of the human IO were determined in multiple gaze positions. Rectus pulleys were directly imaged with intravenous gadodiamide contrast. Images were co...

OBJECTIVE The purpose of the present study was to identify length and landmark of proximal of A1 pulley in hand. MATERIAL AND METHOD An anatomical study of the length and landmark of A1 pulley in hand was performed in 510 fingers and thumbs from 51 preserved cadavers. There were 25 females and 26 males whose ages at the time of death ranged from 48 to 89 years. RESULTS The lengths of A1 pul...

PURPOSE To determine hand surface landmarks and measurements that may be useful in localizing the A1 pulley and digital neurovascular structures in the treatment of trigger thumb. METHODS We highlighted 4 surface landmarks in 20 adult cadaveric hands: the radial border of the index finger, the ulnar border of the thumb, the thumb interphalangeal joint flexion creases, and the thumb metacarpop...