Low-level laser therapy (LLLT) has grown in popularity as a safe method to reduce inflammation, improve circulation, and decrease pain and sensitivity for a myriad of patient populations. Physical therapists commonly use LLLT as an adjunct treatment in conjunction with heat or ice, electrical stimulation, manual therapy, and therapeutic exercise in the treatment of acute knee inflammation from osteoarthritis and similar conditions. By reducing inflammation, patients with both and acute and chronic pain enjoy relief.
First developed in the late 1960s, LLLT gained approval from the U.S. Food and Drug Administration in 2001. Research studies conducted worldwide have shown the modality delivers powerful therapeutic benefits to living tissues and organisms. Nonetheless, whether or not to offer the therapy is often a hot topic in rehab settings because insurance companies generally do not reimburse for its use.
Laser therapy produces photochemical reactions at a cellular level, thereby increasing the production of energy (ATP) available to the cell. The energy increase improves cellular metabolism, enhances blood flow, increases protein synthesis, reduces inflammation, and expedites soft tissue healing rates.
"Research has shown LLLT enhancing ATP production in mitochondria, which provides more energy for cellular healing and tissue recovery," stated Theodosios Neamonitis, PT, DPT, MS, OCS, president of Millennium Physical Therapy. Neamonitis is a member of the Orthopaedic, Private Practice and Sports Physical Therapy sections of the American Physical Therapy Association, and the NYPTA.
LLLT might also improve cellular metabolism, accelerate the process of debris cleaning, and allow all stages of wound healing to proceed more rapidly and efficiently. "The theory is that it temporarily relieves acute and chronic pain, reduces inflammation, increases quality and speed of soft tissue repair, increases blood circulation, stimulates immune function, improves nerve function, stimulates generation of new and healthy tissue, and promotes faster wound healing," Neamonitis explained.
LLLT in Practice
LLLT uses low-powered laser light to stimulate a biological response. "Considering there is a certain amount of cellular healing that occurs after most injuries, LLLT can be applied to expedite that healing of anything from tendinitis and chronic tissue trauma to wound healing," explained Brian Hay, MS, DPT, OCS, director of programs and clinic director of Performance Physical Therapy, and member of the Private Practice Section of the APTA.
"I especially see good results in those where the tissue is fairly superficial, like Achilles tendinopathy and epicondylalgia," said Hay of his patient population at Performance Physical Therapy, a physical therapist-owned outpatient therapy center with nine clinics based throughout Rhode Island. Performance Physical Therapy specializes in orthopedic rehabilitation, spinal injuries, hand therapy, aquatics, women's health, vestibular rehabilitation, balance rehabilitation, running rehabilitation, dry needling, sports rehabilitation, athletic training, and occupational health.
Developed as alternative light sources for LLLT, light-emitting diodes (LEDs) produce light with wavelengths similar to those of lasers, but they are less monochromatic and can only produce superficially penetrating photons.
Superluminous diodes (SLDs) and LEDs are at a different wavelength than laser light, Neamonitis explained. "The combination of the infrared and red lights may produce superior treatment results as compared to laser alone," he said.
Seven therapists at Millennium have been using LED therapy devices for adjunct therapy since 2010. "Most devices use a combination of laser, LEDs and SLDs," Neamonitis said. "This light produces energy to help repair the cells and accelerate the healing process."
Founded in 2004, Millennium Physical Therapy is a physical therapist-owned outpatient practice with four offices in the New York City boroughs of Queens and Brooklyn. The clinics treat patients of all ages with orthopedic problems, sports injuries and neurological conditions.
There are currently no standardized courses to train therapists on the proper use of this modality. "We received training in an in-service conducted by the vendor that sold us the laser units," Neamonitis said. "We have a general consensus as to what intensity of light to use on patients depending on their diagnosis, body part, treatment area to be covered, the number of treatments they have received with the device, and the stage of their condition."
Acute Knee Inflammation
Laser therapy is designed to treat many acute and chronic orthopedic conditions, according to Neamonitis.
He believes patients with inflammatory conditions such as arthritic conditions, trigger points, and tendinopathies respond best to the treatment.
Patients with acute knee inflammation due to arthritic flare-ups present with red, hot and extremely swollen knees, explained Neamonitis. "The range of motion is poor and they try to avoid weight bearing on that side due to the pain," he said. "After cryotherapy, we use the laser at 10 to 12 Joules/cm2 on both the medial and lateral aspect of the joint."
For patients with acute knee inflammation and chronic osteoarthritis, Hay explained, laser therapy will assist in improving circulation to that area. "A 2009 study by Hegedus B. et al. found that patients with knee osteoarthritis reported significantly lower knee pain levels two months after the treatment, as opposed to the group that received a placebo LLLT," he said.
The study examined the pain-relieving effect of LLLT and possible microcirculatory changes measured by thermography in patients with knee osteoarthritis (KOA).
"By increasing the amount of circulation in the knee, laser therapy increases the amount of synovial fluid that can be found within the joint space, ultimately maximizing the amount of joint space and minimizing joint compression that results in osteoarthritis," Hay explained. "If the amount of joint compression can be reduced, then the range of motion in the knee will significantly increase."
Hay believes LLLT is a great adjunct tool in the treatment of osteoarthritis. "Combined with joint mobilizations, stretching and strengthening exercises, I have personally seen patients return to the activities that they had not been able to do for years or months," he said. "This could be anything from difficulty going up and down stairs to returning to playing golf."
Therapists at Millennium Physical Therapy follow up the treatment with manual therapy, such as retrograde massage, passive range of motion, and therapeutic exercise. "Many of these patients return with minimal-to-no swelling following one or two treatments," observed Neamonitis. "This has allowed these patients to quickly return to their prior activity level and improve their quality of life."
Millennium Physical Therapy uses LLLT for many post-operative knee conditions, such as meniscal repairs and ACL repairs, and following fractures such as tibial plateau fractures. "Our theory behind using it with these patient populations is that it will aid in the healing process," Neamonitis said. Millennium also treats patients with tennis/golfer's elbow, carpal tunnel syndrome, and TMJ disorders with very good results.
The physiological effects of LLLT are still theoretical, and there is conflicting research to prove its effectiveness in clinical trials, Neamonitis told ADVANCE. "Studies have focused on its use on all types of conditions," he said. "We know that it's a great adjunct to be used in our treatment programs and can be used in some cases where other modalities may be contraindicated. It is not to be used as a standalone option for any condition."
Rebecca Mayer Knutsen is on staff at ADVANCE. Contact: firstname.lastname@example.org