Mateusz Gładysz FESSH prep

FESSH prep Tendon injuries Intrinsic and extrinsic healing, the three overlapping phases, adhesions as a non essential accompaniment of repair, incomplete recovery of mechanical properties, effect of cyclic tension in vitro

Biology of tendon healing and adhesion formation

Last reviewed v1.0

FESSH-071Tendon injuries●○○ basic

Regarding the biology of tendon healing after injury:

  1. 1.Tendon healing can occur intrinsically, through proliferation of epitenon and endotenon tenocytes, and extrinsically, through cells invading from the surrounding sheath and synovium.

  2. 2.Peripheral adhesions are an essential component of flexor tendon repair, so preventing them compromises healing.

  3. 3.Healing after acute tendon injury is described in three overlapping phases: inflammatory, proliferative and remodelling.

  4. 4.Once remodelling is complete, healed tendon regains the mechanical properties of intact tendon.

  5. 5.In an in vitro model of partially lacerated flexor tendons, cyclic tension enhanced the intrinsic healing response compared with no tension.

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-071
First published
Last reviewed
Version
v1.0
Answer key and explanations — open after answering

  1. 1. Tendon healing can occur intrinsically, through proliferation of epitenon and endotenon tenocytes, and extrinsically, through cells invading from the surrounding sheath and synovium.

    True

    Sharma and Maffulli's review describes both routes: intrinsic healing by tenocytes of the epitenon and endotenon, and extrinsic healing by cells that invade from the sheath and synovium. Manske and colleagues likewise describe flexor tendon repair by both extrinsic peripheral fibroblasts and intrinsic fibroblasts from the tendon itself.

    • Sharma P, Maffulli N. Biology of tendon injury: healing, modeling and remodeling. J Musculoskelet Neuronal Interact. 2006;6(2):181-90. PMID 16849830
    • Manske PR, Gelberman RH, Lesker PA. Flexor tendon healing. Hand Clin. 1985;1(1):25-34. PMID 3912393

  2. 2. Peripheral adhesions are an essential component of flexor tendon repair, so preventing them compromises healing.

    False

    In vitro, lacerated rabbit flexor tendons took part in their own repair without extrinsic cells: epitenon-derived cells removed debris and endotenon cells synthesised new collagen. Manske and colleagues concluded that peripheral adhesions accompany healing but are not essential to it, which supports clinical efforts to limit them.

    • Manske PR, Gelberman RH, Vande Berg JS, Lesker PA. Intrinsic flexor-tendon repair. A morphological study in vitro. J Bone Joint Surg Am. 1984;66(3):385-96. PMID 6699055
    • Manske PR, Gelberman RH, Lesker PA. Flexor tendon healing. Hand Clin. 1985;1(1):25-34. PMID 3912393

  3. 3. Healing after acute tendon injury is described in three overlapping phases: inflammatory, proliferative and remodelling.

    True

    Reviews describe an inflammatory phase, followed by a proliferative phase and then a remodelling phase. Sharma and Maffulli stress that healing is one continuous process whose phases overlap and are separated only for descriptive purposes.

    • Darrieutort-Laffite C, Blanchard F, Soslowsky LJ, Le Goff B. Biology and physiology of tendon healing. Joint Bone Spine. 2024;91(5):105696. PMID 38307405
    • Sharma P, Maffulli N. Biology of tendon injury: healing, modeling and remodeling. J Musculoskelet Neuronal Interact. 2006;6(2):181-90. PMID 16849830

  4. 4. Once remodelling is complete, healed tendon regains the mechanical properties of intact tendon.

    False

    Both reviews state that healed tendon does not recover the properties of uninjured tissue. Sharma and Maffulli note that, despite remodelling, the biochemical and mechanical properties of healed tendon never match those of intact tendon.

    • Sharma P, Maffulli N. Biology of tendon injury: healing, modeling and remodeling. J Musculoskelet Neuronal Interact. 2006;6(2):181-90. PMID 16849830
    • Darrieutort-Laffite C, Blanchard F, Soslowsky LJ, Le Goff B. Biology and physiology of tendon healing. Joint Bone Spine. 2024;91(5):105696. PMID 38307405

  5. 5. In an in vitro model of partially lacerated flexor tendons, cyclic tension enhanced the intrinsic healing response compared with no tension.

    True

    Tanaka and colleagues cultured partially lacerated chicken flexor digitorum profundus tendons with or without cyclic tension. Under tension the laceration was covered by a thicker layer of proliferating fibroblasts aligned with the load and collagen synthesis was stimulated, showing that loading enhanced the intrinsic response in this model.

    • Tanaka H, Manske PR, Pruitt DL, Larson BJ. Effect of cyclic tension on lacerated flexor tendons in vitro. J Hand Surg Am. 1995;20(3):467-73. PMID 7642929