During the initial visit, the investigator will collect several pieces of data from participants that are considered part of the routine care, if you are being seen in the clinic, this information will also be used for research purposes. Initially the investigator will ask participants to provide their age, gender, work status, disability status, type of work, whether a previous pain physician has evaluated or provided treatment in the past, if there is any ongoing litigation, a detailed description of the pain (burning, electrical, shooting…etc.) and its location. If the participants are being seen in the clinic for their normal care a detailed physical examination assessing the motor strength of the upper extremities, sensation to light touch and reflexes that is part of the standard of care will be provided for the participants. The participants will be asked to give a numerical value for their pain (a scale from 0-10 where 0 is no pain and 10 is the worst pain imagined). Two questionnaires will be provided for the participants to complete which are not standard of care. The first one is the EuroQol Group (EQ-5D) which provide an over assessment of the quality of life. The second is a medication log to document their analgesics use. If the participants are being evaluated via telephone call, the same questions will be conducted, but no physical exam will be provided.
The participants will be assigned to either a white, or green light group. The participants have 50% chance of being in either group. Once the participants are assigned a light group, the participants will be given a strip of Light emitting diode, (LED) light that correspond to their color group. The participants will be asked to take and use the LED strip in a dark room in their house every day for two hours to be exposed to the light, the participants will do this for 10 weeks. The study start date and the outcome assessment timeline will begin from the date of your first exposure to the assigned light. The participants will be asked to complete their weekly questionnaires and daily log, these will be given to the participants on their first clinic visit or sent to the participants if they live out of town. There will be several follow up appointments as detailed below. There is a chance the participants may be asked to cross over into a different group from the one the participants were assigned, there will we a 2 week washout period, then return to clinic for light assignment then light exposure for 10 week, similar visits as described below.
For the follow up clinic visit or phone call (Week 10), data similar to the information gathered at the initial visit will be collected. The description of the pain (burning, electrical, shooting…etc.) and its location will be reviewed. A physical examination assessing for pain and sensation to light touch that is part of the standard of care will be provided for the participants. At the end of the study, the participants will be asked to return the LED strip, their logs and questionnaires.
There is an optional blood draw and saliva sample collection for patients that consent to this. Blood and saliva samples will be collected at baseline and end of study, blood draws will be done to look for inflammatory mediators, increased anti inflammatory mediators and endocannabinoids. Saliva samples will be collected to check for melatonin.
