It is a real challenge to the anesthesiologists to differentiate brachial plexus injury (BPI) from myofascial pain syndrome (MPS). The possibility of MPS should be suspected in a patient with complaints of pain and dysfunction of the upper arm immediately after surgery. Here we report a case of gallstone with cervical ankylosing spondylitis who sustained myofascial pain syndrome (MPS) immediately after open cholecystectomy. We utilized dry needle stimulation to deactivate the trigger point of the pectoris minor muscle and stretching the muscle to relieve the muscle pain after the diagnosis was made. The patient completely recovered 2 weeks later.