Brief Answer: It could be due to cervical spondylosis. Detailed Answer: Hello, Thanks for your query. You might suffering from cervical spondylosis. It is a common degenerative condition of the cervical spine. Lump on the back of neck could be due to muscle spasm due to bad posture. I suggest you to consult an orthopaedician nearby for a detailed examination. You may get the X-ray of the cervical spine under his/her guidance to look for arthritis or other changes in your spine. Your doctor after diagnosing the condition may refer you for physical therapy. The physical therapist will help you reduce your pain using stretches. The therapist will show you how to do exercises that make your neck muscles stronger. You can take analgesic and muscle relaxant after discussing with your doctor. You also need some life style modification like- Do not sit for prolonged period of time in stressful postures Do use firm collars while traveling Do not lift heavy weights on head or back Do not turn from your body but turn your body moving your feet first Do turn to one side while getting up from lying down Do the exercises prescribed regularly Do use firm mattress, thin pillow or butterfly shaped pillow I do hope that you have found something helpful and I will be glad to answer any further query. Take care

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