Frozen Shoulder or Rotator Cuff Tear? We know how difficult it can be when shoulder pain interferes with your daily life — from lifting your arm to reaching behind your back, or even sleeping comfortably at night. But not all shoulder pain is the same. Frozen Shoulder: often develops gradually, leading to stiffness and restricted movement. Rotator Cuff Tear: usually causes sharp pain with certain movements, especially when lifting the arm or lying on the affected shoulder. Understanding the diff