Human Cadaver Hands Research Articles

Morphometric analysis of articular cartilages of knee joint using MRI

To identify the anatomical basis of entrapment of radial sesamoid bone of thumb into intercondylar notch of first metacarpal head and to reproduce radiographic “overlapping sign” on sesamoid subluxation.Ten human cadaveric hands were dissected to measure the anthropometric parameters of radial sesamoid bone and intercondylar notch of first metacarpal head. Radiographs were taken to identify and to reproduce “overlapping sign” on sesamoid subluxation into intercondylar notch.Intercondylar notch of first metacarpal head was consistently larger than radial sesamoid bone, which allowed the entrapment. Radiographic “overlapping sign” was reproducible when such subluxation occurred.This anatomical study identifies sesamoid subluxation into intercondylar notch as the cause of first metacarpophalangeal joint rotary subluxation. Radiographic “overlapping sign” is diagnostic of this clinical entity and is an important consideration for open reduction.確認拇指橈端種籽骨陷入拇指掌骨頭髁間凹口的解剖依據和重塑X射線照片中在種籽骨半脫位的重疊徵 兆。解剖並量度10隻人類屍手的橈端種籽骨和第一個掌骨頭髁間凹口的參數。 使用X射線照相確認和重塑在種籽骨半脫位進入掌骨頭髁間凹口的“重疊徵兆”。拇指掌骨頭髁間凹口一致地大於橈端種籽骨，能讓種籽骨陷入其中。 當這樣半脫位發生時，X射線照相中“重疊的徵兆”是可重塑的。這項解剖研究確認橈端種籽骨半脫位陷入拇指掌骨頭髁間凹口，可成為拇指指掌關節旋轉式半脫位的起因。 X射線照相中的重疊徵兆是重要的臨床確診手段及考慮手術復位的關鍵。

Assessing Finger Joint Biomechanics by Applying Equal Force to Flexor Tendons In Vitro Using a Novel Simultaneous Approach.

BackgroundThe flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) are critical for finger flexion. Although research has recently focused on these tendons’ coactivity, their contributions in different tasks remain unclear. This study created a novel simultaneous approach to investigate the coactivity between the tendons and to clarify their contributions in different tasks.MethodsTen human cadaveric hands were mounted on our custom frame with the FDS and FDP of the third finger looped through a mechanical pulley connected to a force transducer. Joint range of motion, tendon excursion and loading force were recorded during individual joint motion and free joint movement from rest to maximal flexion. Each flexor tendon’s moment arm was then calculated.ResultsIn individual motions, we found that the FDP contributed more than the FDS in proximal interphalangeal (PIP) joint motion, with an overall slope of 1.34 and all FDP-to-FDS excursion (P/S) ratios greater than 1.0 with force increase. However, the FDP contributed less than the FDS in metacarpophalangeal (MCP) joint motion, with an overall slope of 0.95 and P/S ratios smaller than 1.0 throughout the whole motion except between 1.9% and 13.1% force. In free joint movement, the FDP played a greater role than the FDS, with an overall ratio of 1.37 and all P/S ratios greater than 1.0.ConclusionsThe new findings include differences in finger performance and excursion amounts between the FDS and FDP throughout flexion. Such findings may provide the basis for new hand models and treatments.

Mini Tightrope Fixation Versus Ligament Reconstruction – Tendon Interposition for Maintenance of Post-trapeziectomy Space Height: A Biomechanical Study

To test the biomechanical stability of ligament reconstruction and tendon interposition (LRTI) compared with Mini TightRope fixation for thumb metacarpal subsidence after trapeziectomy. Fifteen fresh human cadaveric hands underwent trapeziectomy and were divided into 3 treatment groups: LRTI using a biotenodesis screw and single versus dual Mini TightRope fixation. The thumb and index fingers were removed distal to the metacarpal; the distal ends of the metacarpals and proximal radius were potted in urethane resin and mounted onto a servohydraulic testing machine. A cyclic axial load was applied to stress the trapezial cavity. We recorded displacement of the first metacarpal via the position of the actuator head and computed the size of the trapezial space as the difference of the initial size and first metacarpal displacement. Each specimen underwent cyclical loading until the first metacarpal had collapsed completely onto the scaphoid (failure of the repair) or until 6 hours of testing had been completed. The number of cycles to failure, change in the size of the trapezium cavity, and relative change in size of the trapezium cavity were determined. The trapezial space had completely closed before 6 hours of testing were completed in all biotenodesis screw-augmented LRTI specimens and remained present in all single and dual Mini TightRope specimens. Absolute (and normalized) changes in the size of the trapezial cavity in the single and dual Mini TightRope specimens were 11 ± 2 and 10 ± 2 mm, respectively. Dual Mini TightRope fixation provided superior load bearing and maintenance of trapezial space height compared with single Mini TightRope or LRTI biotenodesis screw procedures. This study demonstrates that patients who undergo suture suspension arthroplasty may be able to move earlier because of the immediate stability the construct affords.

Effect of wrist and interphalangeal thumb movement on zone T2 flexor pollicis longus tendon tension in a human cadaver model

IntroductionTherapy after flexor pollicis longus (FPL) repair typically mimics finger flexor management, but this ignores anatomic and biomechanical features unique to the FPL. Purpose of the studyWe measured FPL tendon tension in zone T2 to identify biomechanically appropriate exercises for mobilizing the FPL. MethodsEight human cadaver hands were studied to identify motions that generated enough force to achieve FPL movement without exceeding hypothetical suture strength. ResultsWith the carpometacarpal and metacarpophalangeal joints blocked, appropriate forces were produced for both passive interphalangeal (IP) motion with 30° wrist extension and simulated active IP flexion from 0° to 35° with the wrist in the neutral position. DiscussionThis work provides a biomechanical basis for safely and effectively mobilizing the zone T2 FPL tendon. ConclusionOur cadaver study suggests that it is safe and effective to perform early passive and active exercise to an isolated IP joint. Level of evidenceNA.

Study on accessory thenar branches of median nerve in hand: its surgical importance in carpal tunnel syndrome

Median nerve enters the palm through the carpal tunnel deep to flexor retinaculum of wrist. The median nerve gives off recurrent motor branch (thenar) just distal to flexor retinaculum to innervate thenar muscles of the hand. Objective: In present study the objective was to study the presence of accessory thenar branches and their side of origin. Materials and Methods: The study included 51 human cadaver hands at the Department of Anatomy, Mysore Medical College & Research Institute, Mysore during 2011-13. These specimens fixed in 10% formalin were finely dissected and variations were noted. Results: Out of 51 specimens, accessory thenar branches were present in 26 specimens (51%) i.e. 12 on right (23.5%) and 14 (27.45%) on left. Level of origin was observed within the retinaculum in 5 specimens (9.8%) on right and 2 specimens (3.9%) on left, distal to retinaculum in 7 specimens (13.7%) on right and 12 specimens (23.5%) on left side. Accessory thenar branch was originating from 1 st common digital nerve in 5 specimens (9.8%) on right and 1 specimen (1.96%) on left side, from radial proper digital nerve to thumb in 7 specimens (13.72%) on right, 13 specimens (25.49%) on left side. Conclusion: Knowledge of branching patterns & unusual variations helps in proper treatment of disorders of the median nerve. The possibility of multiple thenar innervations must be considered by hand surgeons in preoperative evaluation to reduce the hazards of iatrogenic injury or postsurgical complications.

Formation Of Superficial Palmar Arch:A Cadaveric Study With Its Clinical Significances

The vasculature of the hand has been a topic of anatomical interest because of wide range of variations in the formation and distribution of palmar arches. In the present study we have emphasized on the varying pattern of the formation and branching pattern of the superficial palmar arch (SPA) in cadaveric human hands. The study was conducted in 42 formalin fixed human cadaveric hands and different presentations were noted. The classic formation of the SPA was noted in 76.6% of the specimens and mostly on the right hand. The other variants noted were SPA completed by the first dorsal metacarpal artery and SPA formed between median and ulnar artery. Incomplete SPA ending in the thenar muscles and an abrupt end between the index and middle finger were also noted in the present study. The existence of both common and rare anatomic variations in the formation of superficial palmar arch as well as the absence of collateral circulation between ulnar and radial arteries necessitates the proper knowledge of vasculature of the hand in order to avoid or minimize the risk of complications during vascular surgeries or reconstructive surgeries in the hand.

Experimental Model of Trigger Finger Through A1 Pulley Constriction in a Human Cadaveric Hand: A Pilot Study

Although it can be reasonably assumed that trigger digits occur as the result of a size mismatch in the pulley-tendon system, it is unclear whether locking, histological changes, and nodule formation occur owing to an intrinsically too small pulley or an enlarged digital flexor tendon. Our purposes in this feasibility study were to (1) create a model of trigger digit by pulley constriction in nonpreserved human tissue, (2) measure the change in work of flexion as the force of pulley constriction increased, (3) compare the work of flexion between nontriggering and triggering conditions, and (4) determine whether triggering can occur at the A2, A3, and A4 pulleys under similar conditions. Using a tensiometer, we studied the work of flexion in 4 fingers (thumb, index, middle, and ring) in a human cadaveric hand. The load of flexion was measured as the A1 to A4 pulleys were incrementally constricted in order to induce triggering. Work of flexion was analyzed for differences among trial conditions. Triggering was successfully induced in all 4 digits through constriction of the A1 pulley. No triggering occurred in any of the A2, A3, or A4 pulley systems in this model. We successfully created a trigger model in a human cadaveric hand. Our results demonstrate that the A1 pulley can cause triggering from manual constriction of the pulley alone. A trigger model such as this may allow investigations of pathophysiology, and this may result in novel treatment strategies and modalities.

Distal attachment of flexor tendon allograft: A biomechanical study of different reconstruction techniques in human cadaver hands

We compared the mechanical force of tendon-to-bone repair techniques for flexor tendon reconstruction. Thirty-six flexor digitorum profundus (FDP) tendons were divided into three groups based upon the repair technique: (1) suture/button repair using FDP tendon (Pullout button group), (2) suture bony anchor using FDP tendon (Suture anchor group), and (3) suture/button repair using FDP tendon with its bony attachment preserved (Bony attachment group). The repair failure force and stiffness were measured. The mean load to failure and stiffness in the bony attachment group were significantly higher than that in the pullout button and suture anchor groups. No significant difference was found in failure force and stiffness between the pullout button and suture anchor groups. An intrasynovial flexor tendon graft with its bony attachment has significantly improved tensile properties at the distal repair site when compared with a typical tendon-to-bone attachment with a button or suture anchor. The improvement in the tensile properties at the repair site may facilitate postoperative rehabilitation and reduce the risk of graft rupture.

The Effect of Suture Preloading on the Force to Failure and Gap Formation After Flexor Tendon Repair

Gap formation is a common and severe complication after flexor tendon repair that can affect the outcome and prolong tendon healing. The purpose of this study was to investigate the effect that a pretensional force applied to the suture during tendon repair has on the repair strength and force that causes gap formation. We used a total of 48 flexor digitorum profundus tendons from 12 human cadaver hands. We employed a core tendon suture, using the modified Pennington technique, and a running suture for flexor tendon repair. Before tying the knots of the core suture, we preloaded the sutures in each tendon end 0, 5, 10, or 15 N for 10 seconds to compare the effect of loading magnitude on repaired tendon peak force to failure and force causing gap formation. The force to form a gap of 2 mm in the 15-N preload group was significantly increased compared with the 0-N and 5-N preload groups. At the 3-mm gap formation, the force of all preload groups was significantly higher than the nonpreload group. The peak force with a preload of 10 N and 15 N was significantly higher than 0-N preload. These findings suggest that pretensioning with 10 to 15 N at the suture-tendon interface before tying the knot has a beneficial effect on both the tendon gap formation and the peak force to failure. When the surgeons perform tendon repair, pretensioning at the suture-tendon conjunction will increase the repair strength.

Stability of Fixation of Proximal Phalanx Unicondylar Fractures of the Hand: A Biomechanical Cadaver Study

To determine the relative stability of various fixation methods for proximal phalanx intra-articular unicondylar fractures during simulated early active motion. We created proximal phalangeal intra-articular unicondylar fractures in 13 fresh-frozen human cadaveric hands. Using a saw through a dorsal approach, we made an osteotomy beginning in the intercondylar notch and extending proximally at a 45° angle to the radial border of the proximal phalanx. We fixed each of the 4 fingers on each hand with a 1.5-mm headless compression screw, a 1.5-mm lag screw, two 1.1-mm smooth K-wires, or one 1.1-mm smooth K-wire. We rotated the order of constructs randomly for each hand. We simulated active range of motion on a custom-loading device at 0.25 Hz from full finger extension to full flexion for 2,000 cycles and measured displacement by a differential variable reluctance transducer. We found no significant differences in displacement of the fracture site among the 4 methods of fixation. Movement in the control specimen with no osteotomy fixation was significantly higher than with each of the other fixation methods. Biomechanical stability did not differ among the fixation methods for proximal phalanx unicondylar fractures in a flexion-extension active range of motion model. Fixation of these fractures with any of the methods tested may provide sufficient stability to withstand postoperative therapy when there is no substantial resistance to active motion.

Comparison of a multifilament stainless steel suture with FiberWire for flexor tendon repairs — an in vitro biomechanical study

Our goal was to investigate and compare the mechanical properties of multifilament stainless steel suture (MFSS) and polyethylene multi-filament core FiberWire in flexor tendon repairs. Flexor digitorum profundus tendons were repaired in human cadaver hands with either a 4-strand cruciate cross-lock repair or 6-strand modified Savage repair using 4-0 and 3-0 multifilament stainless steel or FiberWire. The multifilament stainless steel repairs were as strong as those performed with FiberWire in terms of ultimate load and load at 2 mm gap. This study suggests that MFSS provides as strong a repair as FiberWire. The mode of failure of the MFSS occurred by the suture pulling through the tendon, which suggests an advantage in terms of suture strength.

BIOMECHANICAL PROPERTIES OF EXTENSOR TENDON REPAIR USING THE SIX-STRAND SINGLE-LOOP SUTURE TECHNIQUE: A COMPARATIVE ANALYSIS WITH THREE OTHER TECHNIQUES IN CADAVERIC MODELS

A six-strand single-loop technique has been implemented for repairing extensor tendons. This paper describes an investigation to compare the biomechanical properties of extensor tendons repaired using this technique with three other commonly used techniques, namely the Kessler-Tajima (two-stand) technique, the Tsuge (two-strand) technique, and the modified (four-strand and double-loop) Tsuge technique. Epitendinous stitches were implemented on all techniques. From human cadaveric hands, extensor tendons were harvested, transected, and repaired using these techniques. Tensile test was performed on the repaired tendons to determine the force at the first gap opening, 1-mm and 2-mm gap distances and at the maximum load. We have observed that at the first gap opening, the forces generated in the tendons repaired using the six-strand, Kessler-Tajima, and modified Tsuge techniques are significantly larger than the Tsuge technique. Thereafter, the force generated at gap distances of 1 mm, 2 mm, and the maximum force depend on the number of strands and the epitendinous stitches. In this case, the maximum force (31.80 N ± 4.73 N) from the six-strand technique is significantly higher than that from the Kessler-Tajima technique. In particular, all samples from the six-strand technique failed by suture pull-out. In contrast, suture pull-out is less common for the other techniques; these samples also exhibited suture rupture. This study is important because it reveals that cadaveric tendons repaired using the Kessler-Tajima, modified Tsuge, and six-strand techniques can accommodate higher initial forces (compared to the Tsuge technique) and, thus, are more effective for resisting gap formation. Among these techniques, it is shown that the six-strand configuration is reliable because the strands, rather than breaking, results in pull-out at sufficiently high loads. Thus, the six-strand approach for anchoring the ruptured tissue results in the transfer of large forces to the suture. It is suggested that the six-strand technique may be a viable technique since it requires only a single-loop suture and this may simplify the repair procedure and tendon handling without increasing the bulk of the repaired tendon appreciably.

Immunofluorescent Triple-Staining Technique to Identify Sensory Nerve Endings in Human Thumb Ligaments

Ligament innervation purportedly plays a critical role in stability, proprioception and pathology of joints with minimal bony constraints. The human thumb carpometacarpal (CMC) joint is such a joint: with a complex saddle configuration and wide circumduction, its constraint is primarily ligamentous and it is prone to osteoarthritis. CMC reconstruction is the most commonly performed arthritis surgery in the upper extremity. Little, however, is known about CMC ligament innervation. We describe a novel triple-staining immunofluorescence technique using the markers for low-affinity neurotrophin receptor p75, the pan-neuronal marker protein gene product (PGP) 9.5 and 4′,6′-diamidino-2-phenylindole (DAPI) to simultaneously detect and differentiate between specific sensory nerve endings: the Pacini corpuscles, the Ruffini endings and nerve fascicles. Five primary CMC ligaments (dorsal radial, dorsal central, posterior oblique, anterior oblique and ulnar collateral ligaments) were harvested from 10 fresh-frozen human cadaver hands. Following paraffin sectioning, each ligament was stained using a triple-stain technique and imaged with fluorescence microscopy. Multidimensional acquisition permitted simultaneous capture of images at different wavelengths. Pacini corpuscles were distinguished by their distinct p75 immunoreactive capsules, and Ruffini endings by their overlapping p75 and PGP9.5 immunoreactive dendritic nerve endings. Simultaneous use of PGP9.5, p75 and DAPI immunofluorescence to analyze innervation patterns in human ligaments provides descriptive analysis of staining patterns and receptor structure as well as clues as to the proprioceptive function of CMC ligaments and the joint as a whole. Our novel findings of CMC ligament innervation augment the study of normal and pathological joint mechanics in this joint so prone to osteoarthritis.

Abstracts Presented at the Summer Meeting of the British Association of Clinical Anatomists, Laboratory of Human Anatomy, University of Glasgow, Glasgow, United Kingdom from 21st to 22nd of July, 2010†

Volar plating of distal radius fractures has recently gained favour due to complications associated with external fixation and dorsal plating techniques. The aim of this study was to determine the impact of the incision made in volar fixation on the palmar cutaneous branch of the median nerve (PCBMN). A standard Henry's approach was applied to 10 pairs of human cadaver hands. Further dissection was undertaken to provide morphometric data. The PCBMN was not damaged by the incision in any of the specimens and was absent in two specimens. Mean distances from the origin of the PCBMN to the distal wrist crease (DWC), scaphoid tubercle (ST) and bistyloid line (BSL) were 55.15, 76.04, and 52.38 mm, respectively. From the flexor carpi radialis tendon, ST and radial styloid process the mean distances to the PCBMN were 4.46, 22.82, and 29.07 mm, respectively. The nerve entered the flexor retinaculum at a mean of 10.88, 22.73, and 10.69 mm from the BSL, ST and DWC, respectively. Measurement reliability ranged from ICC 0.98 to 1.00 (intra-observer) and 0.96 to 1.00 (inter-observer). These findings suggest that damage to the PCBMN from this technique is unlikely but knowledge of variants can help minimize the risk of injury.

Cadaveric Study of Locked Thumb Metacarpophalangeal Joint Caused by Entrapment of Radial Sesamoid Bone

Purpose To identify the anatomical basis of entrapment of radial sesamoid bone of thumb into intercondylar notch of first metacarpal head and to reproduce radiographic “overlapping sign” on sesamoid subluxation. Methods Ten human cadaveric hands were dissected to measure the anthropometric parameters of radial sesamoid bone and intercondylar notch of first metacarpal head. Radiographs were taken to identify and to reproduce “overlapping sign” on sesamoid subluxation into intercondylar notch. Results Intercondylar notch of first metacarpal head was consistently larger than radial sesamoid bone, which allowed the entrapment. Radiographic “overlapping sign” was reproducible when such subluxation occurred. Conclusion This anatomical study identifies sesamoid subluxation into intercondylar notch as the cause of first metacarpophalangeal joint rotary subluxation. Radiographic “overlapping sign” is diagnostic of this clinical entity and is an important consideration for open reduction.

Biomechanical Analysis of Partial Flexor Tendon Lacerations in Zone II of Human Cadavers

The aims of this study were to examine nonrepaired 90% partial lacerations of human cadaver flexor digitorum profundus (FDP) tendon after simulated active motion, and to assess the residual ultimate tensile strength. Partial, transverse zone II flexor tendon lacerations were made in the volar 90% of the tendon substance in 10 FDP tendons from 5 fresh-frozen human cadaver hands. The tendons were cycled in the curvilinear fashion described by Greenwald 500 times to a tension 25% greater than the maximum in vivo active FDP flexion force measured by Schuind and colleagues. The tendons were then loaded to failure using the same curvilinear model. No tendons ruptured during cycling. Triggering occurred in 3 tendons. All 3 began triggering early in the cycling process, and continued to trigger throughout the remainder of the 500 cycles. The observed triggering mechanics in each case involved the interaction of the proximal face of the lacerated tendon with Camper's chiasm and the pulley edges during extension. The load to failure value of the 90% partially lacerated tendons averaged 141.7 +/- 13 N (mean +/- standard deviation). Tendon failure occurred by delamination of the intact collagen fibers from the distal, discontinuous 90% of the tendon. Cadaveric transverse zone II partial flexor tendon lacerations have residual tensile strength greater than the force required for protected active mobilization.

Work of Flexion Related to Different Suture Materials After Flexor Digitorum Profundus and Flexor Digitorum Superficialis Tendon Repair in Zone II: A Biomechanical Study

Repair of both flexor digitorum profundus (FDP) and flexor digitorum superficialis (FDS) tendons is commonly performed in zone II flexor tendon injuries; however, the bulk of the repair may impair tendon gliding. We evaluated whether repairing 1 slip of FDS tendon and resecting the other would significantly decrease work of flexion and whether suture material affected this interaction in an in vitro study. The index, middle, and ring fingers from 10 fresh-frozen human cadaveric hands were disarticulated and their tendon sheaths opened. Baseline work of flexion was tested. Lacerations were made in zone II, and then the FDP tendon was repaired with 3 different suture materials: FiberWire, Ticron, and prolene. Work of flexion was again measured and the percentage increase calculated. Further iterations were performed with both slips of FDS tendon repaired and with one slip of FDS tendon repaired and the other resected. There was no significant difference in the work of flexion after repairs done with FiberWire, Ticron, or Prolene. Work of flexion after repair of both FDP and FDS tendons increased 51% compared with an increase of 21% after FDP-only repair and an increase of 9% after repair of one and resection of the other slip of FDS. Repair of both FDP and FDS tendons significantly increased work of flexion. Resection of 1 slip of FDS tendon significantly reduces work of flexion in zone II flexor tendon repair. Suture material had no effect on this interaction.

Tensile Strength of a New Suture for Fixation of Tendon Grafts When Using a Weave Technique

To evaluate a new corner stitch construct for tendon graft or tendon transfer fixation and compare the tensile strength with a conventional central cross-suture design in human cadaver tendons. Flexor digitorum profundus tendons of the index, middle, and ring fingers (48 total) were used as recipients and palmaris longus, extensor indicis proprius, and extensor digitorum communis tendons of the index finger (48 total) were used as grafts from 16 fresh-frozen human cadaver hands. We compared the cross-stitch technique with a new corner stitch technique in tendon repairs made with 1, 2, or 3 weaves (8 per group). Tendons were sutured at each weave with either 2 full-thickness cross-stitches or 4 partial-thickness corner stitches of 4-0 nylon. Mattress sutures also were placed through the free tendon end for each repair type. The tensile strength of the tendon-graft composite was measured with a materials testing machine. The tensile strength of the repairs increased significantly with the number of weaves. When 2 or 3 weaves were used with the corner stitch or when 3 weaves were used with the cross-stitch, the repairs were significantly stronger. Although no significant difference in strength to failure was noted when comparing cross and corner stitches with equivalent numbers of weaves, qualitatively there was a difference in mode of failure with the 3-weave corner stitches failing primarily by intrasubstance tendon failure and the 3-weave cross-stitch repairs failing by tendon pullout. The corner stitch is as strong as conventional cross-stitch repairs and its superficial placement may be more favorable to tendon blood supply. This repair may be advantageous for clinical applications.

Efficacy of a Percutaneous A1 Pulley Release Technique With Identification of Anatomic Differences Between Genders

This cadaver study investigates the efficacy and safety of the Biomet knife and technique for percutaneous A1 pulley release. We also evaluate the anatomic relationship between specific palmar surface landmarks and relevant underlying structures and identify differences between genders. Eighty percutaneous A1 pulley releases, excluding the thumb, were performed on 20 fresh human cadaver hands (10 male, 10 female). Complete release was obtained in 60 of 80 fingers. Success rates for each surgeon improved markedly as the study progressed. There were no significant differences between males and females regarding the distance between a standardized incision site and the proximal edge of the A1 pulley. A learning curve exists for percutaneous A1 pulley release using the Biomet knife and technique. The extended distal palmar crease is a reasonable incision site for percutaneous release of the index, middle, and ring A1 pulleys in both men and women as the A1 pulley begins just distal to this surface landmark.

Anatomic Basis of Dorsal Finger Skin Cover

This study describes the anatomy of the dorsal cutaneous vascular system of 180 digits (36 thumbs, index, middle, ring, and little fingers) from 18 pairs of fresh human cadaver hands. The aim of this paper is to incorporate the anatomic data into the current way of designing the homodigital adipofascial turnover flap for cutaneous coverage of the dorsum of the finger. We have carried out an anatomic study in preserved cadaver hands to define the distance between the joint and the origin of the dorsal cutaneous branches of the proper palmar digital artery in the proximal and middle phalanx of the long fingers and for the thumb to metacarpal and interphalangeal joint. All branches of the proper digital artery that ran to the dorsal skin were then identified, and their diameters and the distances of their origins from the proximal interphalangeal joint were measured. We showed that 2 constant branches in the proximal and middle phalanx from each proper digital artery have consistent sites of origin at predictable distances from the proximal interphalangeal joint for the long fingers and the metacarpal and interphalangeal joint for the thumb. The flap survival was excellent, and no donor site complications were observed. We showed that these branches have consistent sites of origin at predictable distances from the proximal interphalangeal joint. The adipofascial turnover arterial flap has appeared as an excellent alternative to achieve early coverage of cutaneous wounds at the dorsal aspect of the fingers.