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Pointing light at musculoskeletal and neurological conditions: clinical applications 113

• If you want to stimulate healing of a fracture or an
osteotomy, treat that area as just the wound that
lies over it and focus most of the energy around it.
For instance, if a TTA plate has been placed on the
medial surface of the proximal tibia, treat the surgi-
cal wound over it as a regular acute wound and treat
more intensely proximal and distal to it, as well as
on the cranial, lateral, and caudal side of the tibia.
Once the wound has healed you may treat the whole
area with similar higher parameters, but not focus-
ing over the implant, rather around it for a better
penetration into the fracture/osteotomy line.
• If and when osteomyelitis develops, LT may help
decrease bacterial counts as described in an experi-
mental model. [188] You will improve the metabolism
of the area, and almost certainly see an improve-
ment, but if you are dealing with osteomyelitis
between the bone and the plate, your chances of
success are limited and a full resolution is unlikely
unless other therapies are combined with LT.

9.3 Tendon and ligament injuries

Fibroblast replication and collagen production provide
the base for tendon and ligament repair. LT helps to
produce proportionally more type I collagen, which
has a better spatial arrangement, and leads to greater
final tensile strength of tendons and ligaments, as has
been consistently demonstrated in several experimen-
Figure 9.3 Surgical site infection and wound dehiscence over tal models. [138, 140, 143, 292, 293] And blood flow, one of the
a metallic implant. Laser is indicated (see Case nos. 20–22 in major benefits of LT, is also a critical factor in the repair
this chapter). of these already poorly vascularized structures – if you
are an orthopedic surgeon, this is one of your usual
proliferate, differentiate, get more attached to the tita- concerns.
nium implant, and produce more TGF-β. [235] In animal There have been some animal models studying LT in
models of normal and osteopenic bone, LT can acceler- inflammation after tendon and ligament injuries. The
ate implant integration and new bone formation. [163] It mechanism is similar to other tissues: there is a reduc-
enhances osteogenic mediators such as bone morpho- tion in the expression of pro-inflammatory mediators,
genic protein, and even one session has been proven to such as COX-2, in both acute and chronic inflamma-
increase the bone–implant interface strength. [291] The tory phases. [294] Models also show the effect of LT in the
sooner an implant is integrated and vascularized, the surrounding tissues: in rats, 15 sessions of laser therapy
2
less likely it is to be colonized by bacteria. So using LT at 10 J/cm were able to prevent some of the morpho-
to treat patients with osteosynthesis implants is not just logical degenerative changes and proteoglycan loss that
possible, it is advisable, and could help prevent osteo- occurred after cruciate ligament transection, although
myelitis (you can read more about LT in infected tissue in this particular model IL-1 did not decrease. [295]
in section 5.6). Another placebo-controlled experimental study, using
If there is a metallic plate placed on the bone, laser a model in rabbits that developed progressive osteoar-
will not penetrate the plate to reach the bone, which thritis (OA) after cranial cruciate ligament transection,
has two immediate implications. described how LT could decrease knee pain, synovial

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