Mateusz Gładysz FESSH prep

FESSH prep Tendon injuries Mechanical effect of core suture repair, accuracy of visual estimation near the repair threshold, outcome of non suture treatment with early motion, mechanism of triggering, trimming for triggering

Partial flexor tendon lacerations

Last reviewed v1.0

FESSH-080Tendon injuries●●○ intermediate

Regarding the management of partial lacerations of the digital flexor tendons:

  1. 1.In a canine model of partial flexor tendon lacerations, tendons repaired with a core suture had lower breaking strength at five weeks than tendons left unrepaired.

  2. 2.Surgeons' visual estimates of the size of a partial laceration are least accurate for small lacerations well below the usual threshold for repair.

  3. 3.In Wray and Weeks' series of partial lacerations involving 25–95% of the tendon cross-section, treatment without suture and with early motion gave excellent function in most patients and no tendon ruptured.

  4. 4.A partial flexor tendon laceration can cause triggering when the injured tendon surface catches within the pulley system.

  5. 5.In a cadaver study of 50% and 75% partial flexor tendon lacerations, a running-suture repair glided with less resistance than trimming of the lacerated portion.

FESSH marking: +1 per correct statement, 0 for blank, −1 for incorrect. Click the same TRUE/FALSE button twice to clear it.

Question ID
FESSH-080
First published
Last reviewed
Version
v1.0
Answer key and explanations — open after answering

  1. 1. In a canine model of partial flexor tendon lacerations, tendons repaired with a core suture had lower breaking strength at five weeks than tendons left unrepaired.

    True

    Bishop and colleagues compared repair and no repair, with immobilisation or early protected motion, in a canine model of 60% partial lacerations. Modified Kessler tenorrhaphy had significant adverse effects on breaking strength, stiffness and energy absorption at 35 days. Grewal and colleagues likewise found higher ultimate loads and stiffness in non-repaired than in repaired canine tendons.

    • Bishop AT, Cooney WP, Wood MB. Treatment of partial flexor tendon lacerations: the effect of tenorrhaphy and early protected mobilization. J Trauma. 1986;26(4):301-12. PMID 3959135
    • Grewal R, Saw SS, Bastidas JA, Fischer KJ, Sotereanos DG. Passive and active rehabilitation for partial lacerations of the canine flexor digitorum profundus tendon in zone II. J Hand Surg Am. 1999;24(4):743-50. PMID 10447166

  2. 2. Surgeons' visual estimates of the size of a partial laceration are least accurate for small lacerations well below the usual threshold for repair.

    False

    In Pritsch and colleagues' cadaver study, the mean absolute error of surgeons' and residents' estimates was 11%, but accuracy fell for lacerations of 50–70%, close to the 60% threshold for repair. In that range an incorrect management decision would have been made 17% of the time, compared with 7% outside it.

    • Pritsch T, Wong C, Sammer DM. Accuracy of Visual Estimates of Partial Flexor Tendon Lacerations. J Hand Surg Am. 2015;40(12):2421-6. PMID 26527592

  3. 3. In Wray and Weeks' series of partial lacerations involving 25–95% of the tendon cross-section, treatment without suture and with early motion gave excellent function in most patients and no tendon ruptured.

    True

    Wray and Weeks treated 26 patients with 34 partial lacerations (mean 60% of the cross-section) without tendon suture and with early mobilisation. Twenty-three patients obtained excellent function, no tendon ruptured and one trigger finger resolved spontaneously. They still advised a few simple sutures for bevelled lacerations of more than 25%.

    • Wray RC, Weeks PM. Treatment of partial tendon lacerations. Hand. 1980;12(2):163-6. PMID 7409620

  4. 4. A partial flexor tendon laceration can cause triggering when the injured tendon surface catches within the pulley system.

    True

    A partially divided tendon may still transmit flexion force, while its injured surface catches during tendon excursion. Human cadaver work demonstrated impingement against pulley edges and Camper’s chiasm. A partial tear can therefore cause triggering or locking despite retained movement.

    • Manning DW, Spiguel AR, Mass DP. Biomechanical analysis of partial flexor tendon lacerations in zone II of human cadavers. The Journal of hand surgery. 2010;35(1):11-8. PMID 20117303
    • Lineberry KD, Shue S, Chepla KJ. The Management of Partial Zone II Intrasynovial Flexor Tendon Lacerations: A Literature Review of Biomechanics, Clinical Outcomes, and Complications. Plastic and reconstructive surgery. 2018;141(5):1165-1170. PMID 29351182
    • Sahr ME, Trehan SK. Partial Flexor Tendon Injury Causing Locking: Illustration of the Utility of Dynamic Ultrasound. Journal of hand surgery global online. 2023;5(4):488-490. PMID 37521537

  5. 5. In a cadaver study of 50% and 75% partial flexor tendon lacerations, a running-suture repair glided with less resistance than trimming of the lacerated portion.

    False

    Erhard and colleagues lacerated 36 cadaveric flexor digitorum profundus tendons by 50% or 75%. Tendons repaired with a running suture had higher mean gliding resistance than trimmed tendons, strength did not differ between treatments, and eight unrepaired tendons triggered or became entrapped; the authors suggest trimming as an alternative to repair when triggering occurs. Kennedy and Dias reached the same conclusion in turkey tendons.

    • Erhard L, Zobitz ME, Zhao C, Amadio PC, An KN. Treatment of partial lacerations in flexor tendons by trimming. A biomechanical in vitro study. J Bone Joint Surg Am. 2002;84(6):1006-12. PMID 12063336
    • Kennedy JA, Dias JJ. Effect of triggering and entrapment on tendon gliding properties following digital flexor tendon laceration: in vitro study on turkey tendon. J Hand Surg Eur Vol. 2014;39(7):708-13. PMID 23735810