Ultrastructural comparison of medial collateral ligament repair after single or multiple applications of GaAlAs laser in rats

Gabriel Y.F. Ng, Dicky T.C. Fung, Mason C.P. Leung, Xia Guo

Research output: Journal article publicationJournal articleAcademic researchpeer-review

19 Citations (Scopus)


Background and Objectives: To examine single versus multiple applications of a gallium aluminum arsenide (GaAlAs) laser on the ultrastructural morphology of surgically injured medial collateral ligaments (MCLs) in rats. Study Design/Materials and Methods: Sixteen rats were studied with 12 receiving right MCL transection and 4 receiving sham injury. Group 1 (n = 4) received one session of laser (31.6 J/cm2) immediately after injury. Group 2 (n = 4) received 9 doses of transcutaneous laser (3.5 J/cm2). The controls (Group 3, n = 4) received one session of placebo laser, while the sham Group 4 (n = 4) received no treatment. Ultrastructural analyses were done with electron microscopy at 3 weeks. Results: The mass-averaged diameters of collagen fibril in the core and periphery of MCLs treated with multiple laser were larger than the control and those with single laser treatment (P < 0.05). However, the sham injured group had larger fibrils than all other groups (P < 0.05). Conclusions: The repairing MCLs had smaller collagen fibrils than the sham injured ligaments. Multiple laser treatments enhanced the collagen growth in the repairing MCLs at 3 weeks after injury, which are superior to a single treatment with similar dosage.
Original languageEnglish
Pages (from-to)317-323
Number of pages7
JournalLasers in Surgery and Medicine
Issue number4
Publication statusPublished - 17 Nov 2004


  • Collagen
  • Electron microscopy
  • Healing
  • Laser
  • Ligament

ASJC Scopus subject areas

  • Surgery
  • Dermatology

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