Recently, there is a increasing evidence that the addition of low-level laser therapy (LLLT) to treatment program of shoulder problems plays an important role in stimulation of healing, augmenting tissue repair, relief of pain and inflammation, and restoration of function. LLLT, phototherapy or photobiomodulation refers to the use of photons at a non-thermal irradiance to alter biological activity. The basic biological mechanism behind the effects of LLLT is thought to be through absorption of red and near infrared light by mitochondrial chromophores, in particular cytochrome c oxidase (CCO) which is contained in the respiratory chain located within the mitochondria, and perhaps also by photoacceptors in the plasma membrane of cells. It is hypothesized that this absorption of light energy may cause photodissociation of inhibitory nitric oxide from CCO9 leading to enhancement of enzyme activity, electron transport, mitochondrial respiration and adenosine triphosphate (ATP) production. In turn, LLLT alters the cellular redox state which induces the activation of numerous intracellular signaling pathways, and alters the affinity of transcription factors concerned with cell proliferation, survival, tissue repair and regeneration.~During rotator cuff tear healing stages, there are complex interactions between a variety of tissue growth factors and cells, ultimately resulting in tissue that is markedly different from that of normal, uninjured tendon. Hence, there is a strong drive to investigate the role of potential therapies in the form of biological augments that may restore the pathologic tissue to a near normal physiological state. In this context, LLLT may be an effective choice in the treatment of nonoperative small and medium-sized rotator cuff tears (RCT). To the best of our knowledge, there is no randomized controlled study investigating the effects of the LLLT in patients with a RCT size not exceeding 3 cm. Therefore, the aim of the current study is to investigate all the possible effects of the LLLT in terms of functional status, pain-free mobility, and quality-of-life.
During rotator cuff tear healing stages, there are complex interactions between a variety of tissue growth factors and cells, ultimately resulting in tissue that is markedly different from that of normal, uninjured tendon. Hence, there is a strong drive to investigate the role of potential therapies in the form of biological augments that may restore the pathologic tissue to a near normal physiological state. In this context, low-level laser therapy (LLLT) may be an effective choice in the treatment of nonoperative small and medium-sized rotator cuff tears (RCT). To the best of our knowledge, there is no randomized controlled study investigating the effects of the LLLT in patients with a RCT size not exceeding 3 cm. Therefore, the aim of the current study is to investigate all the possible effects of the LLLT in terms of functional status, pain-free mobility, and quality-of-life.