Feasibility of partial A2 and A4 pulley excision: residual pulley strength

Identifying Palmar Skin Surface Landmark for Locating A2 Pulley during Cadaveric Dissection of the Hand

The A2 and A4 pulleys are fibro-osseous structures that support the flexor tendon function. Injury to these pulleys can result in bowstringing and limited tendon excursion. Thus, having an understanding of the skin surface landmark of the A2 pulley is crucial to safeguard it during hand surgery.

Methods

We performed cadaveric dissection of 62 hands. For 248 fingers, the measurement of distance A, which is half the distance between the palmar digital crease and proximal interphalangeal crease reflected in the palm, and distance B, which is the distance between the A2 pulley's starting point and the palmar digital crease, were taken by a caliber. Statistical analysis was performed using the paired sample t test to determine whether there was a significant difference between distances A and B.

Results

Our study revealed that there was no significant difference (p>0.05) between the measured starting point of the A2 pulley and its proposed surface landmark for the index, middle, and small fingers. Conversely, the ring finger showed a statistically significant difference of 1 mm more proximal.

Conclusions

By measuring the distance between the palmar digital crease and proximal interphalangeal crease and reflecting it proximally in the palms, one can anticipate the location of the A2 pulley's starting point for each digit, except for the ring finger. The ring finger's starting point is 1 mm more proximal than the other digits. Knowing the starting point of the A2 pulley will help hand surgeons limit incisions and avoid accidental injury during hand surgery.

High-resolution ultrasound tendon-to-bone distances in partial and complete finger flexor A2 pulley ruptures simulated in human cadaver dissection: toward understanding imaging of partial pulley ruptures

Introduction: The A2 pulley tear is the most common injury in rock climbing. Whereas complete A2 pulley ruptures have been extensively researched, studies focused on partial A2 pulley ruptures are lacking. A2 pulleys rupture distally to proximally. High-resolution ultrasound imaging is considered the gold-standard tool for diagnosis and the most relevant ultrasound measurement is the tendon-to-bone distance (TBD), which increases when the pulley ruptures. The purpose of this study was to establish tendon-to-bone distance values for different sizes of partial A2 pulley ruptures and compare these values with those of complete ruptures. Material and methods: The sample consisted of 30 in vitro fingers randomly assigned to 5 groups: G1, no simulated tear (control); G2, simulated 5 mm tear (low-grade partial rupture); G3, simulated 10 mm tear (medium-grade partial rupture); G4, simulated 15 mm tear (high-grade partial rupture); and G5, simulated 20 mm or equivalent tear (complete rupture). A highly experienced sonographer blinded to the randomization process and dissections examined all fingers. Results: The tendon-to-bone distance measurements (medians and interquartile ranges) were as follows: G1, 0.95 mm (0.77-1.33); G2, 2.11 mm (1.78-2.33); G3, 2.28 mm (1.95-2.42); G4, 3.06 mm (2.79-3.28); and G5, 3.66 mm (3.55-4.76). Significant differences were found between non-torn pulleys and simulated partial and complete pulley ruptures. Discussion: In contrast, and inconsistent with other findings, no significant differences were found among the different partial rupture groups. In conclusion, the longer the partial pulley rupture, the higher the tendon-to-bone distance value. The literature is inconsistent regarding the tendon-to-bone distance threshold to diagnose a partial A2 pulley rupture. The minimum tendon-to-bone distance value for a partial rupture was 1.6 mm, and tendon-to-bone distance values above 3 mm suggest a high-grade partial pulley rupture (15 mm incision) or a complete pulley rupture.

Feasibility of Homodigital Flexor Digitorum Superficialis transposition, a new technique for A2-C1 pulleys reconstruction: A kinematic cadaver study

INTRODUCTION

Homodigital flexor digitorum superficialis transposition (HFT) is proposed as a new technique for A2-C1 pulley reconstruction. Flexor digitorum superficialis is transposed on the proximal phalanx and inserted on the pulley rims, crossing over flexor digitorum profundus and acting as a pulley.

MATERIALS AND METHODS

The kinematic feasibility was investigated in a cadaveric bowstring model (after A2 and C1 pulley removal) on 22 fingers (thumb excluded).

RESULTS

HFT was effective in restoring the correct flexion of proximal and distal interphalangeal joints, compared to bowstring model. No adverse events were registered.

CONCLUSION

HFT is a feasible technique. Clinical application is encouraged.

Zone 2 Flexor Tendon Repair Location and Risk of Catching on the A2 Pulley

PURPOSE

To determine the region of the flexor digitorum profundus (FDP) and flexor digitorum superficialis (FDS) tendons in zone 2 that, when involved by a laceration repair, will reliably catch on the A2 pulley after surgery.

METHODS

Using fresh-frozen cadavers (5 hands, 20 digits), excursions of the FDP and FDS tendons were measured in relation to the A2 pulley. The C1, A3, and C2 pulleys were resected. The digit was maximally flexed by applying traction to the flexor tendon in the forearm. An 8-0 suture tag was placed in the flexor tendons immediately distal to the A2 pulley. The digit was then passively fully extended to measure tendon excursion. Measurements were repeated with 50% venting and 100% release of the A4 pulley. Reference points such as tendon insertions and flexion creases were obtained. This protocol was repeated sequentially for the index, middle, ring, and little fingers.

RESULTS

For all 20 fingers, the suture placed into the FDP just distal to the A2 pulley with the finger fully flexed traveled 1.6 ± 1.9 mm distal to the proximal edge of the A4 pulley with passive extension of the finger. The mean excursion for the FDP was 24.6 ± 3.2 mm, and 16.9 ± 3.1 mm for the FDS. The mean A2 pulley length was 16.2 ± 3.5 mm, and the mean distance between the distal edge of the A2 pulley and the proximal edge of the A4 pulley was 23.0 ± 3.3 mm. Venting the A4 pulley 50% and 100% increased FDP excursion a maximum of 0.9 and 1.9 mm, respectively.

CONCLUSIONS

An FDP repair proximal to the A4 pulley will slide under the A2 pulley with full active digital flexion after surgery. If the distal FDP stump lies underneath the A4 pulley with the digit fully extended, the FDP repair will not likely engage the A2 pulley with full flexion after surgery. The FDP excursion can be reliably predicted as a percentage of the A2 (distal) to the A4 (distal) pulley distance. Most importantly, the distance between the repair site and the A4 pulley approximately equals the length of the A2 pulley that requires release to avoid postoperative triggering.

CLINICAL RELEVANCE

Knowledge of this high-risk region of flexor tendon repair will guide surgeons regarding the potential need for partial release of the A2 pulley.

Flexor tendon pulley V–Y Plasty: an Alternative to Pulley Venting or Resection

Zone 2 flexor tendon repairs can require “venting” or partial resection of the A2 and/or A4 pulleys. We propose and biomechanically assess a technique used by the authors in which the A2 and A4 pulleys are divided and repaired using a V–Y plasty. Two groups of cadaveric fingers were used, one group for assessing the A2 pulley and the second for assessing the A4 pulley. Prepared fingers were mounted onto custom-made jigs, tested using a servohydraulic testing machine and assessed for load to failure. The loads obtained were 75N (SD = 26N) and 234N (SD = 73N) for the A4 and A2 pulleys, respectively. These loads are well in excess of those one would anticipate during a postoperative active mobilization protocol. Tendon pulley V–Y plasty creates a mechanically sound pulley and maintains sufficient cover of the underlying tendon. This technique provides access to perform a tendon repair and/or permits free tendon gliding post-repair, thus providing an attractive alternative to simply “venting”, or resecting, an otherwise troublesome pulley.

Management of complications of flexor tendon injuries

Innovations in operative techniques, biomaterials, and rehabilitation protocols have improved outcomes after treatment of flexor tendon injuries. However, despite these advances, treatment of flexor tendon injuries remains challenging. The purpose of this review is to highlight the complications of flexor tendon injuries and review the management of these complications.

Evidence-based flexor tendon repair

The goal of flexor tendon repair is to achieve normal range of motion of the finger or thumb. The surgical approach depends on the level of injury. Multistrand core suture repairs are recommended for primary flexor tendon repair. It is evident that at least 4 strands are required to an initiate and active range of motion protocol. The epitendinous suture can also increase the strength of the repair. Careful attention to the post-operative therapy regiment is critical to a successful repair.

Release of the A4 pulley to facilitate zone II flexor tendon repair

During primary or delayed primary repair of the flexor digitorum profundus tendon, surgeons often face difficulty in passing the retracted tendon or repaired tendon under the dense, fibrous A4 pulley. The A4 pulley is the narrowest part of the flexor sheath, proximal to the terminal tendon. Disrupted tendon ends (or surgically repaired tendons) are usually swelling, making passage of the tendons under this pulley difficult or even impossible. During tendon repair in the A4 pulley area, when the trauma is in the middle part of the middle phalanx and the A3 pulley is intact, the A4 pulley can be vented entirely to accommodate surgical repair and facilitate gliding of the repaired tendon after surgery. Venting the pulley does not disturb tendon function when the other major pulleys are intact and when the venting of the A4 pulley and adjacent sheath is limited to the middle half of the middle phalanx. Such venting is easily achieved through a palmar midline or lateral incision of the A4 pulley and its adjacent distal or/and proximal sheath, which helps ensure a more predictable recovery of digital flexion and extension.

Importance of proximal A2 and A4 pulleys to maintaining kinematics in the hand: a biomechanical study

PURPOSE

The A2 and A4 pulleys have been shown to be important in finger flexor tendon function. Other authors have suggested either reconstruction or venting of portions of these pulleys in an attempt to preserve finger function in certain clinical situations. This study examines the effects of partial incision of these pulleys on finger flexion kinematics and biomechanics.

METHODS

The index and ring fingers of 16 cadaveric hands were studied. The flexor digitorum profundus tendon was isolated and attached to a computer driven servo-motor. Micro-potentiometers measured flexion angles of the metacarpophalangeal, proximal inter-phalangeal and distal inter-phalangeal joints. Joint inertial torques were calculated making use of this experimental kinematic data.

RESULTS

Proximal 50 % incisions of either the A2 or the A4 pulleys resulted in a statistically significant decrease in overall finger motion. This effect was greatest in the proximal inter-phalangeal joint, with a decrease in joint motion, as well as an earlier time to initiation of motion. These changes in finger motion were more pronounced with A2 pulley incision than they were with A4 pulley incision, but the changes were statistically significant in either case. No significant changes in joint inertial torques were shown.

CONCLUSIONS

Our data provides evidence to the importance of the proximal portions of the A2 and A4 pulleys, and may support partial distal incision of these pulleys in certain clinical situations.

Considerations in the surgical use of the flexor sheath and pulley system

The use of the digital flexor sheath to reconstruct damaged structures in the fingers is an intriguing but under-investigated subject. The sheath is anchored firmly to the phalanges and palmar plates and has well-vascularized outer and synovial inner layers. The middle layer is strong and fibrous and not all of it is required for its main biomechanical function of maintaining the moment arm of the flexor tendons. These characteristics have led to several descriptions of different reconstructive uses. In sheath reconstruction, flaps can be used to repair damaged A2 and A4 pulleys. As an anchor, the sheath is useful for tenodeses and tendon transfers. It has been used in the correction of ulnar claw and swan neck deformities. In ligament reconstruction, the A1 pulley has been used to reconstruct the transverse intermetacarpal ligament in cleft hand and ray amputations. The sheath has also been used to cover tendon repairs and periosteal defects with the aim of decreasing adhesions. There is potential for further use of the flexor sheath in reconstructive surgery. The digital flexor sheath can be used to restore various finger functions providing its physiological roles are recognized and preserved. This review considers the different techniques described and their potential uses.

Clinical outcomes of zone II flexor tendon repair depending on mechanism of injury

PURPOSE

To determine whether mechanism of injury affects outcomes of Zone II flexor tendon repairs.

METHODS

We retrospectively analyzed patients who underwent Zone II flexor tendon repair between 2001 and 2010 with a minimum of 12-month follow-up. Exclusion criteria included fingers with fracture, pulley reconstruction, or flexor tendon bowstringing. The saw group injuries were from saws or from tearing mechanisms; the sharp group had clean transection injuries from knives or glass. At final evaluation, primary outcomes were total passive motion (TPM) and total active motion (TAM) at the proximal interphalangeal and distal interphalangeal joints. Secondary comparisons included strength, Disabilities of the Shoulder, Arm, and Hand (DASH) score, percentage of postoperative tendon rupture, and percentage of patients requiring secondary surgery. The saw group had 13 patients with 17 fingers studied. The sharp group had 21 patients with 24 fingers studied. All patients had primary flexor digitorum profundus repairs in Zone II. Operative records review confirmed for all but 1 patient that flexor digitorum profundus injuries were repaired with a minimum of a 4-strand core suture technique. In the saw group, 9 of 14 fingers with a 50% or greater laceration of flexor digitorum superficialis were repaired; in the sharp group, 15 of 18 such flexor digitorum superficialis injuries were repaired. Average follow-up was 4 years (range, 1-9 y).

RESULTS

The saw group had significantly less TAM and TPM compared with the sharp group. There was no significant difference in DASH scores, strength measurements, or tendon rupture rates. The rate of secondary surgery was significantly higher in the saw group.

CONCLUSIONS

Tearing types of injury, such as those caused by saws, led to poorer outcomes for Zone II flexor tendon injuries compared with sharp injuries at an average follow-up of 4 years. Our results can be useful when discussing expected outcomes. Mechanism of injury in Zone II flexor tendon lacerations may eventually help define optimal treatment.

Biomechanical comparison of techniques to reduce the bulk of lacerated flexor tendon ends within digital sheaths of the porcine forelimb

PURPOSE

Zone II flexor tendon repairs may create a bulging effect with increased bulk and resistance to tendon gliding. A biomechanical time 0 study was performed to assess 2 methods of tendon antibulking for work of flexion and strength characteristics.

METHODS

We placed 24 fresh-frozen porcine forelimb tendons in a custom jig. Deep flexor tendon was sectioned just distal to the intact A1 and A2 pulleys. Specimens were divided into 3 groups before repair: group 1, nonmodified tendon; group 2, 30 degrees bilateral notch excised from both tendon ends; and group 3, triangular longitudinal central wedge excised from both tendon ends. All repairs used a 4-strand modified Kessler core suture and running circumferential epitendinous suture. Work of flexion, 2-mm gap formation, and ultimate load to failure were tested.

RESULTS

Both antibulking techniques (groups 2 and 3) had significantly less work of flexion than group 1 (36.3 and 34.9 J vs 142.9 J, p < .001). There was no significant change in work of flexion between groups 2 and 3 (p > .05). There was no significant difference in terms of 2-mm gap formation among the 3 groups (p > .05). Groups 1 and 3 exhibited a significantly higher load to failure compared with group 2 (p < .05).

CONCLUSIONS

The antibulking repair techniques used in this study decrease the work of flexion with no significant change in force to 2-mm gap formation. Group 2, however, did have significantly lower load to failure. These techniques might be beneficial in zone II flexor tendon injury, in which the tight annular pulley system restricts tendon gliding. However, this is a time 0 study and the potential adverse effects of increase tendon manipulation and trauma were not analyzed, which might increase adhesions and scar during the healing phase of tendon repair.

The influence of concentric and eccentric loading on the finger pulley system

In this study we investigated the influence of the loading condition (concentric vs. eccentric loading) on the pulley system of the finger. For this purpose 39 cadaver finger (14 hands, 10 donors) were fixed into an isokinetic loading device. The forces in the flexor tendons and at the fingertip were recorded. In the concentric loading condition A2 and A4 ruptures as well as alternative events such as fracture of a phalanx or avulsion of the flexor tendons were almost equally distributed, whereas the A2 pulley rupture was the most common event (59%) in the eccentric loading condition and alternative events were rare (23.5%). The forces in the deep flexor tendon, the fingertip and in the pulleys were significantly lower in the eccentric loading condition. As the ruptures occurred at lower loads in the eccentric than in the concentric loading condition it can be concluded that friction may be an advantage for climbers, supporting the holding force of their flexor muscles but may also increase the susceptibility to injury.

Strength measurement and clinical outcome after pulley ruptures in climbers

PURPOSE

Ruptures of the finger flexor pulleys are the most frequent injuries in rock climbers. Whereas multiple pulley injuries demand a surgical reconstruction, single ruptures are mainly treated conservatively. Nevertheless, the question of the clinical outcome or a persisting finger strength deficit after conservative therapy arises.

METHODS

Twenty-one rock climbers (age 34 +/- 9 yr) with a grade 2-4 pulley injury were reevaluated 3.46 (range: 0.25-18) yr after injury. The clinical evaluation followed a standard questionnaire in combination with an ultrasound examination in extension and forced flexion. In order to determine the finger strengths, the subjects hung with the respective finger in various postures on a ledge attached above a door frame, while standing on a force platform, which measured the relative release.

RESULTS

The 21 subjects had old (3.46 yr, range: 0.25-18) pulley injuries in 27 fingers (10 A2, 1 A3, 11 A4, 3 A2/3, 2 A3/4). The clinical outcome was excellent (Buck-Gramcko score of 3) in all cases; the subjects regained their climbing level within a year. There was no difference between the initial ultrasound examination and the follow-up during the study. For 17 finger pairs, data for the relative strength of the injured and the respective healthy finger could be gathered. The finger strength was not significantly different for the injured and the healthy finger in either the hanging or the crimping finger position.

CONCLUSIONS

Nonsurgical treatment of single pulley ruptures is recommended. The clinical outcome was good to excellent, and no long-term strength deficit for the injured finger could be observed.

La plastie d'expansion en Oméga « Ω ». Une nouvelle technique d'expansion des poulies annulaires du tunnel digital fléchisseur

The authors report a new technique of pulley plasty of the flexor digital system. It is not an operative procedure to reconstruct a damaged pulley but an original way to expand the volume of an intact pulley in order to adapt its volume to the diameter of the repaired flexor tendon. The flexor tendons ruptures in Verdan zone II and particularly in Tang zones IIA and IIB are often accompanied by an osteofibrous tunnel injury. Initially, the tendon sheath closure was advised after tendons repair. This sheath recovery had to have an effect on tendons nutrition by establishing the synovial cavity continuity and particularly to protect the tendons from adhesions formation. The closure of the digital tube was rapidly shown to be unnecessary creating an obstacle to the tendons movements without any effect on tendons healing. In primary tendon management, the tendon repair is associated with an increase of the tendon diameter. An incongruence appears with the surrounding digital tube with gliding resistance complicating the tendon injury recovery. In secondary tendon injury management, the flexor digital tube is subject to healing and inflammatory process. This situation with the absence of the flexor tendon generates a retraction with a collapse of the digital tunnel over the injured area. This incongruence between the repaired flexor tendons and the narrowed digital tube required a release of the retracted zone to restore an adequate volume. The only way reported is the "Venting" of a part or the total length of the pulley. This procedure even if it resolves the tendon gliding resistance, is still unacceptable. Indeed it destroys an important anatomical structure of the flexor tendon dynamic system. The flexor pulley Omega plasty "Omega" consists in releasing the lateral palmar attachment of the pulley enhancing its internal volume and increasing the flexor tendon gliding area. The digital tube is composed by the succession of five annular and three cruciform pulleys. The cruciform pulleys are thin and flexible. They retract during the digital flexion assuring the continuity of the digital tube, while the annular pulleys are thicker and fill a biomechanical function. There are two types of annular pulleys: the joint pulleys as A1, A3 and A5; they are attached to the palmar plates of the MP, PIP and DIP joints respectively. During the digital movement, they retract approximately 50% of their length. The osseous pulleys as A2 and A4 are fixed over the lateral and palmar borders of the first and the second phalanx respectively. It is on these pulleys that the Omega plasty is practised. The operative procedure is simple. It consists on a periosteal dissection over the one lateral border of the phalanx. The liberation is undergone palmarly releasing the lateral attachment of the pulley. It respects the anatomical continuity of the pulley and its mechanical properties. Indeed, the continuity of the pulley is fully respected with the periosteal flap of the digital tube floor maintaining sufficient attachment to the pulley to resist to the flexor tendon forces. The level of the flexor tendon injury and the digit position during the initial trauma will determine the level of tendon resistance and where the pulley plasty must be made. If the flexor zone II injury occurred with the digit in an extension position, the tendon conflict appears with the A2 pulley, while it arises with the A4 pulley if the digit was in flexed position. The Omega plasty creates the ideal conditions for an optimal flexor tendon movement recovery. It is a simple and a reproducible procedure. It doesn't distort the mechanical properties of the pulley and the digital tube. We used this pulley Omega plasty fifteen times in twelve patients. In 60% of the cases, the injury concerned the dominant hand, and in 67% of the cases, it was a work accident. In eight of our cases, the omega plasty was done in emergency at the same time of flexor tendon repair, while in the other seven cases, the pulley Omega plasty accompanied the late flexor tendon repair forgotten during the initial trauma management. In ten cases, the plasty concerned the A4 annular pulleys, while in the other five cases, it concerns the A2 annular pulleys. Four cases necessitate a secondary tenolysis three months after the tendon repair. Two patients moved out and cannot be included in our results. On the thirteen-remainder cases, nine retrieved a full digital flexion particularly those who underwent digital tenolysis, while the other four cases retrieved a satisfying digital function in spite of the partial DIP flexion. In our hand, the pulley Omega plasty "Omega" becomes almost a systematic procedure in conjunction with the flexor tendon repair. It offers the ideal conditions for a tendon healing and a physiological flexor tendons motion recovery.

Biomechanics of the flexor tendons

This article examines basic tendon biomechanics, the anatomy and mechanics of digital flexor tendons, and the digital flexor pulley system. It also explores the various models that have tried to simulate the motion of the flexor tendons and several testing modalities that have been used. Finally, clinical applications are considered, including the biomechanics of flexor tendon repairs and tendon transfers. As we reach limits in the care of flexor tendon injuries, research into molecular, biochemical, and micromechanical methods of tendon repair will become the forefront of future investigation.

Pulley rupture and reconstruction in rock climbers

Hand-grip techniques in modern rock climbing generate climbing-related injuries, especially at the flexor tendon sheath level. The most frequent injury is A2 pulley rupture. The clinical diagnosis is based on bowstringing of the flexor tendon and confirmed by computed tomograph scan or magnetic resonance imaging. The surgical procedure is based on an extensor retinaculum graft to reconstruct the ruptured pulley. It is the only efficient treatment regardless of the time between accident and surgery. Thanks to this surgical procedure, patients recover or improve their former climbing performance. Some precautions before climbing may prevent this injury, and these are listed.

The effect of partial A2 pulley excision on gliding resistance and pulley strength in vitro

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 edge or from the proximal toward the distal edge. The peak gliding resistance between intact or repaired tendon and partially excised pulley was measured. After the gliding resistance test the pulley breaking strength and stiffness were measured.

RESULTS

The peak gliding resistance exhibited the same statistical trends for the intact tendon and the repaired tendon groups. In the intact tendon groups the sequential excision of the A2 pulley from the distal toward the proximal edge had no significant effect on peak gliding resistance. With the A2 pulley cut from the proximal toward the distal edge, however, there was a significant increase in peak gliding resistance with 25% remaining pulley distally (0.82 N) compared with intact (0.42 N), 75% (0.57 N), and 50% (0.63 N) pulley remaining proximally. The 25% distal portion of the A2 pulley had a significantly higher breaking strength than the 25% proximal portion (160 N vs 96.7 N, respectively). Similarly the stiffness was greater in the distal portion compared with the proximal portion (120 N/mm vs 70.5 N/mm).

CONCLUSIONS

After A2 pulley excision the size and location of the remaining pulley affects the resulting gliding resistance, stiffness, and failure strength. At the most extreme excision level tested the residual 25% distal segment of the pulley exhibited significantly greater peak gliding resistance compared with the 25% proximal segment, as well as greater strength and stiffness. If excision of the A2 pulley is limited to 50% (either proximally or distally), however, there is little increase in gliding resistance and the retained strength of the pulley is substantial. These data support the clinical practice of partial pulley excision, up to a limit of 50%, to facilitate exposure and tendon repair.

[Flexor tendon pulley system: anatomy, pathology, treatment]

Flexor tendon pulley has been very early noticed and described. Terminology usually accepted recognizes 6 arcifom pulleys (A0 to A5) and 3 cruciform pulleys (C1 to C3). Anatomy and physiology of this flexor tendon gliding and reflection system at the level of the digital sheet are exposed. The integrity necessity of this system became obvious regarding the flexor tendons repair. Four main pathologies may be concerned: the trigger finger congenital or progressive, due to a chondroid metaplasia of the A1 pulley; tenosynovial ganglions arising at the weak point between A1 and A2 pulley; lesions of the flexor tendon sheet during traumatic lacerations or surgical repairs; quite experimental lesions creating isolated ruptures of one or several pulleys which occur during sport practice, especially high level rock climbing. The repair techniques are exposed to allow to graduate and hierarchy the reparation technique regarding the pathology. A2 and A4 repair is always indicated. The best reconstruction material is an extensor retinaculum graft. But its poor surface available often draws to use conventional palmaris longus free graft.