Anatomy of the flexor tendon sheath and pulleys of the thumb

doi:10.1016/S0363-5023(77)80101-9

The Journal of Hand Surgery

Volume 2, Issue 2, March 1977, Pages 149-151

https://doi.org/10.1016/S0363-5023(77)80101-9 Get rights and content

Studies of the pulley systems of the flexor tendon of the thumb demonstrate one oblique and two annular pulleys. Significant decrease in angular motion of the distal joint resulted when both the proximal annular pulley and the oblique pulley were removed, but isolated loss of either did not affect the motion appreciably. If the oblique pulley was intact, then loss of the distal annular pulley did not result in significant loss of motion.

References (6)

LittlerJ.W.
Free tendon grafts in secondary flexor tendon repair
Am. J. Surg.
(1947)
BoyesJ.H. et al.
Flexor tendon grafts in the fingers and thumb
J. Bone Joint Surg
(1971)
LittlerJ.W. et al.
Primary repair of flexor tendons
J. Bone Joint Surg
(1960)

There are more references available in the full text version of this article.

Cited by (100)

The Impact of Dividing the Flexor Tendon Pulleys on Tendon Excursion and Work of Flexion in a Cadaveric Model
2021, Journal of Hand Surgery
The A2 and A4 pulleys of the flexor tendon system have traditionally been considered critical components of efficient digital flexion. This dogma has recently been challenged. Using fresh human cadaveric hands and a model to measure force and excursion, we sought to clarify the clinical importance of releasing different pulleys.
Combinations of A1, A2, and A4 pulleys were released on the index, middle, ring, and little fingers of fresh, cadaveric hands. The excursion was measured as the distance the tendon was pulled by the motor to achieve palm touchdown. The force applied by the motor was constant (25 N); work was derived from the product of force and excursion (distance). The change in excursion and work needed to achieve palm touchdown before and after pulley release was measured. Excursion varies among digits and specimens at baseline; therefore, the percentage change from the intact state was used to compare groups. We compared A2 versus A1, A4 versus A1, A4 versus A2, A1 + A2 versus A2, and A1 + A4 versus A4.
Isolated A2 or A4 release had the greatest individual impact on the excursion (4.77% ± 1.52% and 3.88% ± 1.93%, respectively). When A1 was released with A2 (9.90% ± 2.52%), the additional impact on the excursion was significant; however, when A1 was released with A4 (2.63% ± 2.81%), the impact was marginal. No clinically or statistically significant change in the work of flexion was detected.
A1 release was clinically significant when added to A2 release but not when added to A4 release. Sacrifice of the A2 and A4 pulleys resulted in a statistically significant, but clinically negligible, difference in flexor tendon excursion. These data suggest that the A1 pulley should be preserved when other proximal pulley components are likely to be compromised. These data also add further support to the concept that the A2 pulley or the A4 pulley can be released as needed for optimal tenorrhaphy.
During flexor tendon repair, the length of contiguous pulley release may have more impact on final tendon excursion than which specific pulleys are released.
Flexor pollicis longus zone 2 tendon repair under WALANT with ultrasound assistance
2021, Trauma Case Reports
A feature of the flexor pollicis longus tendon injury is the frequency of palmar retraction so that a wrist approach is needed for retrieval of the proximal stump. We are reporting on our first outpatient zone T2 flexor pollicis longus tendon repair under WALANT with ultrasound guidance. In the event of zone T2 flexor pollicis rupture, ultrasound location of tendon extremities is used to plan surgical WALANT strategy and to guide the injection of lidocaine with epinephrine whilst limiting the injected volume to what is strictly necessary.
Outcome of percutaneous trigger finger release technique using a 20-gauge hypodermic needle
2021, Journal of Clinical Orthopaedics and Trauma
Citation Excerpt :
Annular pulleys are thickening of the tendon sheath in five areas along the flexor tendons of the 2nd to 5th finger and numbered as A1 to A5, while thumb has only two annular pulleys (A1 and A2). The tendon sheath is made up of two components - membranous synovial portion and retinacular pulley portion.8 The membranous synovial portion of the sheath is composed of a visceral or epitenon layer intimate with the tendon and a parietal or outer layer that maintains the synovial pouch.
Trigger finger or stenosing tenosynovitis is a disproportion between the volume of the tendon sheath and its contents. This disproportion prevents gliding of the tendon as it moves freely through the annular pulley. The technique of percutaneous release of the annular pulley for trigger finger has been described well in the literature, which has undergone several modifications, like use of hypodermic needle, tenotome or specially designed knives.
We performed percutaneous trigger finger release using a 20-gauge hypodermic needle to know the outcome and efficacy of the technique post release. A Prospective cohort study was conducted in 80 consecutive trigger fingers of 67 patients who were treated by percutaneous release using 20-gauge hypodermic needle. Quinell’s grading system was used to quantify severity of triggering and pain was assessed using visual analogue scale (VAS) before and after the procedure. Patients were evaluated based on these two parameters at timely interval and final outcome was assessed at the end of one year.
Out of 80 digits treated, most of the subjects were in the age group 40–50 years (39.07%). Most common grade of trigger finger observed was Grade 3 (60%) followed by Grade 4 (30%) with VAS score of 8 (46%) followed by VAS score of 7 (24%) before release. At a year follow-up 95% of patients improved to grade 0 and mean VAS score was 0.44. Three patients developed scar tenderness, which gradually subsided by analgesics and physiotherapy with no other major complications.
Our technique of percutaneous release of trigger digit with 20 G needle is effective and can be performed safely with ease. It is cost efficient and has a short learning curve with great acceptance being an outpatient procedure.
Evaluation and Treatment of Flexor Tendon and Pulley Injuries in Athletes
2020, Clinics in Sports Medicine
Kinesiology of the wrist and the hand
2020, Comparative Kinesiology of the Human Body: Normal and Pathological Conditions
This chapter introduces the kinesiology of the wrist joint and the hand both in normal and pathologic conditions. It starts by presenting detailed anatomy and biomechanics of the wrist in the first part of the chapter. The stability philosophy of wrist joint is explained, and the instability patterns are presented. The pathomechanics of wrist injuries are also discussed. In the second part, anatomy and biomechanics of hand are presented in detail, including its flexor and extensor system and the intrinsic mechanism. The pathomechanics of hand injuries are also discussed in a clinical view.
Result of A1 pulley reconstruction after closed rupture of the thumb pulleys during childbirth
2018, Hand Surgery and Rehabilitation
Closed rupture of the thumb flexor tendon pulleys is rare. Although anatomical and biomechanical studies have exposed the roles played by the pulleys in flexor pollicis longus (FPL) function, no standardized surgical management has yet been defined, in contrast to situations where pulley reconstruction is required in the fingers. We describe a case of rupture of the three pulleys in the thumb that probably occurred after violent thumb grasp during childbirth in the absence of any other trauma. We reconstructed the A1 pulley only using an extensor retinaculum graft because no remnants of the native pulleys were present.
La rupture fermée des poulies du flexor pollicis longus (FPL) reste une pathologie rare. Bien que des études anatomiques et biomécaniques aient révélé l’implication de chaque poulie dans la fonction du FPL, il n’existe aucune prise en charge standardisée, contrairement à la reconstruction des poulies des doigts longs. Nous présentons un cas de rupture des trois poulies du pouce pendant un accouchement probablement après une prise violente du pouce sans aucun autre traumatisme. Nous avons procédé à la reconstruction de la seule poulie A1 en utilisant un greffon du rétinaculum des extenseurs en absence des reliquats de la poulie native.

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Anatomy of the flexor tendon sheath and pulleys of the thumb

Am. J. Surg.

Flexor tendon grafts in the fingers and thumb

J. Bone Joint Surg

Primary repair of flexor tendons

J. Bone Joint Surg