Hello. Thanks for asking from HCM. I can understand your concern. The injury over neck must have caused some injury to neck muscles. This soreness in neck muscle increases on stretching it. So while moving neck towards left side and thus stretching it, leads to pain. You can also check it by pressing at injury area leading to pain. It can be managed by following simple tips : Apply cold compresses if swelling and redness : Gradual stretching of neck. You can take help of physiotherapist : You can give him painkiller like Diclofenac sodium after proper prescription. : You can apply painkiller gel like Diclofenac gel at pain site. : Avoid pressure at injury site : Ask him to lie supine while resting. Do not use large size pillow while lie on side. If he is not able to move neck at all or having new onset of focal weakness or having abnormal sensation in neck radiating upto arm/fingers, you must show him to doctor. He might be having spinal injury. The doctor will examine him and may advise tests like X ray cervical spine and MRI cervical spine to rule out fracture/spinal cord or nerve injury. Further treatment will be decided after reports. Cord compression or unstable spine may require surgery. Rest conditions can be managed conservatively by painkillers and neck immobilisation. Hope it will help you. Thanks. Take care. Dr Ishu Bishnoi