Physiological action of Photobiomodulation using 650 nm diode laser for treating frozen shoulder: a comprehensive review

Abstract Frozen shoulder (adhesive capsulitis) is a debilitating condition characterized by progressive shoulder pain and restricted range of motion. Photobiomodulation (PBM) therapy, using a 650 nm diode laser, has emerged as a promising non-invasive treatment modality. To investigate the physiological mechanisms and therapeutic efficacy of 650 nm diode laser photobiomodulation in treating frozen shoulder. A comprehensive review of the current literature on PBM mechanisms, cellular responses, and clinical applications in the treatment of frozen shoulder was conducted. Focus was placed on 650 nm wavelength therapeutic protocols and outcomes. PBM at 650 nm wavelength demonstrates significant therapeutic effects through mitochondrial cytochrome c oxidase activation, leading to increased ATP production, reduced inflammatory mediators, enhanced collagen synthesis, and improved tissue repair mechanisms. Clinical studies have shown significant pain reduction, improved range of motion, and accelerated functional recovery in patients with frozen shoulder. 650 nm diode laser PBM therapy represents an effective, non-invasive treatment option for frozen shoulder through well-established cellular and molecular mechanisms that promote tissue healing and pain resolution.