Nd: YAG Laser Therapy for Gonarthrosis: A Controlled Study Using Thermography and Ultrasound Guidance

Dr. Juan Manuel Saucedo Padilla, Dra. Paola Rosales Esquivel, Dr. Jorge Luis Cabrera Renteria

Abstract: This study evaluated the clinical efficacy of Nd: YAG laser therapy for treating gonarthrosis through neuromodulation of geniculate nerves, using thermography and ultrasound for precision. Forty patients underwent treatment over a two - week protocol. Results showed substantial pain reduction, improved activity levels, and minimal adverse effects. While patients with comorbidities like diabetes and smoking showed comparatively limited gains, overall results support the therapy?s role in non - invasive management of knee osteoarthritis. Continued research is needed to validate long - term effectiveness and generalizability. Background: The behavior of body temperature depends on multiple variables and is quite complex, today it is known that an excess or point of temperature is usually related to an acute process, usually overuse, that is, if for example, one knee is hotter than the opposite, it may indicate increased blood flow, likely due to mechanical overload, repetitive stress, or prior trauma, being overloaded, compensation or even a previous operation or inflammation. On the contrary, a body area that is colder than the contralateral may indicate a lack of activity, a vascular problem, nervous inhibition or protection.14 It is generally expected that both limbs exhibit thermal symmetry. When there is a thermal asymmetry, this may indicate that there is some alteration, probably related to decompensations, imbalances, overloads and ultimately injury risks, which may appear even before the person has pain or discomfort. Method: The purpose of this study is to evaluate the efficacy of Nd: YAG laser therapy in reducing pain and improving function in patients with gonarthrosis. The laser was administered at a wavelength of 810 nm and a power of 100 mW at 8 points around the knee for two weeks in 40 patients diagnosed with gonarthrosis who met the inclusion criterio. Findings: Patients decreased their final VAS scores, with changes in daily activity limitations ranging from moderate to normal.27 improved their activities (67.5%) and from moderate to partial (32.5%).38 became sedentary (95%), and 2 had a moderate change in sedentary behavior (5%). Only 2 intensity parameters were high in 19 patients (22.5%) and 21 patients had low parameters (52.5%). Interpretation: Treatment with NdYAG laser together with the support of a thermographic camera is confirmed for patients with grade I, II and III gonarthrosis, reducing pain up to 6 months after the intervention.

Keywords: Nd: YAG laser, Gonarthrosis, Thermographic imaging, Neuromodulation, Knee osteoarthritis