Can Laser Therapy be used to Treat Meniscal Injuries?
Low-Level Laser Therapy in Meniscal Pathology: a Double-Blinded Placebo-Controlled Trial
Malliaropoulos N, Kiritsi O, Tsitas K, Christodoulou D, Akritidou A, Del Bueno A, &
Maffulli N. Lasers in Medicine and Science. Epub ahead of print October 24, 2012. DOI:10.1007/s10103-012-1219-8
A meniscal injury is the most common cause of symptomatic knee pain. Due to the inability of the meniscus to heal, current management of these injuries involves symptomatic management, and surgery as needed. Low-level laser therapy (LLLT) for soft tissue injuries has become increasingly apparent in recent years, with claims of reduction in pain, inflammation, as well as accelerated healing time. It is currently being used for these possible benefits; however, its effectiveness for treating meniscal tears is still unknown. Therefore, the purpose of this double-blind placebo-controlled study was to assess the effectiveness of LLLT in 64 patients with symptomatic medial meniscus injuries. Half of the patients were randomized to receive LLLT and the other half was randomized to receive sham treatment. The results were compared between the two groups using a visual analog scale (VAS) for knee pain, Lysholm Knee Scoring System (knee pain and function), and swelling of the knee. The LLLT group demonstrated significant improvements from baseline at all time points (i.e., 4 weeks, 6 months, 1 year post treatment). Furthermore, at 4 weeks post treatment, the VAS and Lysholm scores were significantly improved in the LLLT when compared to the sham group.
LLLT demonstrated effectiveness in a population with symptomatic meniscal pathology. It still remains unclear as to mechanistically why LLLT may have had superior outcomes. Some theories include an analgesic effect of LLLT which could have been caused by improved healing and decreased pain-receptor stimulation. Depth of penetration of any laser therapy is limited (~ 5mm) due to superficial tissues absorbing the energy. It would have been interesting if this study had taken a follow-up MRI to determine if there had been any structural changes that occurred within the involved knees. This would appropriately address whether or not healing is actually occurring, or if the LLLT slows ensuing degenerative changes that may be occurring in the sham group. Also, if LLLT has the ability to decrease inflammation, this would be reinforced if the authors of the study assessed biochemical markers of the involved joint. The findings of this study are certainly exciting as to the future possibilities, but there still remains much to be answered. The authors looked at a very specific set of inclusion criteria for meniscal injury; I wonder what the applicability may be across other types of meniscal or even other knee pathologies. I also wonder if these patients went on to have surgery or if this prevented the need for surgical intervention. And lastly, what are the long-term effects of this on degenerative changes of the knee. Clinically, I am not sure how many athletic training programs have lasers. Does anyone have any experiences using one? What kind of outcomes have people seen?
Written by: Nicole Cattano
Reviewed by: Stephen Thomas
Related Posts:Malliaropoulos N, Kiritsi O, Tsitas K, Christodoulou D, Akritidou A, Del Buono A, & Maffulli N (2012). Low-level laser therapy in meniscal pathology: a double-blinded placebo-controlled trial. Lasers in Medical Science PMID: 23093133