17-08-2012, 03:08 PM
Laser in Orthopedic Surgery
b767F-LASER-PRESENTATION.ppt (Size: 674 KB / Downloads: 34)
LASER
LLLT is a complementary form of treatment and, therefore, is not intended to replace other electrotherapeutic modalities, such as medication, Physiotherapy, ultrasound, interferential therapy, and magnetic therapy. In a number of therapeutic applications, however, LLLT has been rated more highly in its effectiveness than these other modalities (Baxter et al, 1991).
Laser Construction
A laser is constructed from three principal parts:
An energy source (usually referred to as the pump or pump source),
A gain medium or laser medium, and
Two or more mirrors that form an optical resonator
Laser Tissue Interactions:
Thermal
Caused by elevated temperature after absorption of laser energy
Nearly all wavelengths and exposure durations
Photochemical
Caused by chemical reactions within body tissue after absorption
of laser energy
Only with wavelength less than 0.550 m
Dominant effect for exposure durations greater than 10 sec
Laser Bioeffects And Concepts of NHZ, MPE, etc.
Shockwave (Acoustic)
An explosive effect when short pulses are absorbed on the retina
Pulse duration less than 10 sec
Laser Tissue Interactions:
Photochemical Interaction
The laser energy is absorbed by metabolically active pigments of the mitochondria in various cutaneous and subcutaneous layers: here involved are the two enzymes of the oxidation chain, Cytochrome a/a3 and Flavoprotein with absorption maxims of wavelengths applied.
It is supposed that the changes in the stereochemical conformation induced by an electro magnetic field leads to an increase in activity and improves the concentration of ATP by up to 200%. In addition, an increase in oxygen and glucose metabolism is observed. The main effect is an optimized function of the Na-K pump at the cell membrane, an increased protein synthesis (prostaglandin, enzyme) and a significantly higher rate of mitosis.
Cellular Activities
Increased cell metabolism (Increased cell function)
Increased collagen synthesis (Increased healing of soft tissues)
Increased osteoblast production (Increased healing of bone)
Increased circulation
Increased formation of new capillaries (tiny blood vessels) by release of growth factors
Increased T-cell production (Increased immune function)
Increased production of neurotransmitters such as endorphins, serotonin, ACTH etc. (Increased nerve function)
Increased chronic pain threshold through decreased C-fiber activity (Decreased pain)
Physiological Effects of Laser
Accelerated tissue healing and repair by 40%
Increased tensile strength in tissue repair
Increase callous and bone formation
Reduced or eliminated pain
Decreased edema and inflammation
Improved immune response
Stimulates nerve function
Promotes Cellular Oxygenation/Detoxification
Diagrammatic events
Diagrammatic events how laser reduces inflammation & pain, and affects tissue healing:
a. Inflammation
b. pain
c. Tissue healing
Subsides inflammation by:
1. Stabilization of cellular membrane
2. ATP production and synthesis
3. Vasodilatation is stimulated via Histamine,
Nitric Oxide (NO) and Serotonin.
Acceleration of leukocytic activity.
5. Increased Prostaglandin synthesis,
6. Reduction in Interleukin 1(IL-1).
7. Enhanced lymphocyte response.
8. Increased angiogenesis.
9. Temperature modulation.
10. Enhanced superoxide dismutase
(SOD) levels.
11. Decreased C-reactive protein and
neopterin levels.
Reduces pain by:
1. Increase in b-Endorphins.
2. Blocked depolarization of C-fiber afferent nerves.
3. Increased nitric oxide production.
4. Increased nerve cell action potential.
5. Axonal sprouting and nerve cell regeneration.
6. Decreased Bradykinin levels.
7. Increased release of acetylcholine.
8. Ion channel normalization.
Reduces healing time by:
1. Enhanced leukocyte infiltration.
2. Increased macrophage activity.
3. Increased neovascularization.
4. Increased fibroblast proliferation.
5. Keratinocyte proliferation.
6. Early epithelialization.
7. Growth factor increases.
8. Enhanced cell proliferation and differentiation.
9. Greater healed wound tensile strength.
Conclusion
Over the past 20 years, laser and LED devices has been widely being used in medical science with proved & promising success for treatment of a variety of medical conditions including carpal tunnel syndrome, cervical neck pain, low back pain, joint pain, frozen shoulder, generalized muscle pain. and acceleration of wound healing. Besides orthopedic application, Laser is being successfully used in other medical branches ( Surgery, Eye, ENT, Gastroenterology, Neurosurgery etc.).
There are thousands of research, study and medical applications, that LASER is a very effective modality of treatment . It is being widely used all over the world with promising and successful also in Orthopedic surgery which is very target oriented, convenient and cost effective.
NASA are currently using technical light therapy( Laser) for medical conditions in space applications.
All of these events validate the growing acceptance in mainstream medicine for the medical efficacy of laser therapy as a viable, often superior therapeutic treatment modality.