To begin, ask the participant to lie on the back with the examined knee straight, and the pelvis in a neutral position. Ensure that the insertion area is close to the myofascial trigger point or MTrP for single and small MTrPs. Measure some of the pain and functional findings associated with knee osteoarthritis.
Next, sterilize both the surface of the insertion point and the practitioner's fingers. To perform Fu's Subcutaneous Needling or FSN, gently remove the protective sheath of the FSN needle, fix the FSN needle in the slot of an FSN inserting device, and pull the fix and groove back into the locked position. Pulled and pushed the device into the desired insertion area to create an indentation at approximately 15 degrees to the skin.
Quickly pierce the subcutaneous, and press the control button with the index finger. Once the FSN needle has popped out and penetrated the skin layer, remove the FSN needle from the fixation slot with the other hand, and remove the needle insertion device. Flatten the needle and carefully push it until it is fully inserted.
When pushing forward, slightly raise the needle tip to see if the skin bulge moves with the needle tip. At this stage, ensure that the hand is relaxed and free of resistance, and that the patient does not feel any movement under the skin, soreness, swelling, or numbness. Once the soft casing pipe is completely under the skin, withdraw the needle core handle by approximately three millimeters, and turn 90 degrees to the left so that the bulge on the bed of the cannula enters the groove of the needle core handle.
Next, locate the insertion point of the FSN needle at the proximal one third of the line from the superior border of the patella to the anterior superior iliac spine. To perform the swaying movement, using the needle entry point, slightly remove the needle holder from the skin, and with the thumb as the fulcrum, keep the index, middle, and ring fingers in a straight line. Keep the middle finger and thumb face-to-face against the needle and alternate the index and ring fingers back and forth in a smooth, soft, fan-like swing movement.
To perform the reperfusion approach technique, ask the participant to perform three cycles for a total of one minute of a dorsiflexion movement with the sole of the foot, with each cycle consisting of 10 seconds of continuous movement, and 10 seconds of rest. Ask the participant to perform three cycles of sitting down and flexing, and extending their knee joints for a total of one minute, with each cycle consisting of 10 seconds of continuous movement and 10 seconds of rest. Ensure that the range of motion is as large as possible, under safe conditions, and is preferably slow.
After completing the swaying movement and reperfusion approach, remove the FSN needle. The described protocol was implemented in a clinical setting with 31 participants. The study results showed that the FSN group significantly improved pain characteristics as measured by the visual analog scale or VAS.
The study also revealed a significant difference in the pressure pain threshold, or PPT of the quadriceps muscle in the FSN group, indicating improved muscle and tendon qualities. The functional index questionnaire assessment revealed that the FSN group demonstrated significant enhancements in the WOMAC and Lequesne index scores, reflecting improvements in physical function, pain, and stiffness. The results also establish the effectiveness of FSN treatment in alleviating the soft tissue pain associated with knee osteoarthritis caused by MTrPs.