Preliminary study of the immediate effect of high intensity high frequency TENS to the nonoperative limb on movement-evoked pain in patients with femoral neck fracture after surgery

Abstract

Transcutaneous electrical nerve stimulation (TENS) is a non-pharmacological intervention used in clinical settings. High intensity high frequency (HI-HF) TENS has been recently used to increase the intensity of pain tolerance in patients. A few minutes of HI-HF TENS is an effective stimulus to trigger a diffuse analgesic response; stimulating a site distant from the pain site may also produce analgesic effects. Therefore, it is considered that the analgesic effect on the operative limb can be obtained by performing HI-HF TENS on the nonoperative limb, which is generally not affected by surgery. This study aimed to examine the immediate effect of HI-HF TENS to the nonoperative limb on movement-evoked pain in patients who have undergone a surgery for femoral neck fracture. HI-HF TENS was applied to the nonoperative limb that was unaffected by surgery. Six patients who underwent femoral neck fracture surgery were assigned to receive standard programs plus HI-HF TENS applied to their nonoperative limb for 7 days after surgery. Movement-evoked pain was significantly attenuated after TENS, compared to that before TENS. Thus, the application of HI-HF TENS to the patients’ nonoperative limb may reduce postoperative movement-evoked pain.