Patients with arthritis typically describe a deep ache within the shoulder joint. Initially, the pain feels worse with movement and activity, and eases with rest. As the arthritis progresses, the pain may occur even when you rest. By the time a patient sees a physician for the shoulder pain, he or she often has pain at night. This pain may be severe enough to prevent a good night’s sleep. The patient’s shoulder may make grinding or grating noises when moved. Or the shoulder may catch, grab, clunk or lock up. Over time, the patient may notice loss of motion and weakness in the affected shoulder. Simple daily activities like reaching into a cupboard, dressing, toileting and washing the opposite armpit may become increasingly difficult.