Hi, Thanks for posting in HCM. I understand your concern. Voltaren Gel contains diclofenac , which is a nonsteroidal anti-inflammatory drug (NSAID). Diclofenac works by reducing substances in the body that cause pain and inflammation and hence is used to treat pain in the joints of neck, shoulder, hands, wrists, elbows, knees, ankles or feet. Diclofenac can increase your risk of fatal heart attack or stroke, especially if you use it on a long term basis or take high doses, or if you have heart disease. It is recommended not to use Voltaren Gel just before or after heart bypass surgery (coronary artery bypass graft, or CABG). It would be ideal for you to consult Orthopedic Surgeon in this regard for evaluation and proper prescription of the medication that suits your condition to get relieved from shoulder pain and stiff neck symptoms. Hope the information provided would be helpful. All the best.