OBJECTIVETo explore the relationship between the needling sensation of catgut embedding therapy and the depth of embedded catgut so as to improve the safety of the needle insertion and catgut implantation of the therapy.

METHODSTwenty healthy adults were selected. Under the ultrasound, the structure of the cervical Jiaji (EX-B 2) was observed. In the ultrasound guidance, the catgut was embedded. The two-dimensional imaging method was adopted to observe the anatomic structure and the procedure of needle insertion at the cervical Jiaji (EX-B 2). The high-frequency ultrasound was used to collect the images at Jiaji (EX-B 2) of C5 and determine the depths from the skin surface to the different layers of the point. Additionally, the visual analogue scale (VAS) was adopted to score the needling sensations when the needle inserted at different layers. The persistent sensation duration in the local area was followed continuously.

RESULTSUnder the ultrasound, the anatomic structure and tissue layers of cervical Jiaji (EX-B 2) were displayed clearly. The difference was significant in the average depth from the skin surface to the subcutaneous tissue, trapezius, splenius capitis, semispinalis capitis, semipinalis cervicis, multifidus and vertebral arch between the males and females (all P<0. 01). During the needle insertion, the sensations were apparently different when the implantation went to different layers. The qi arrival presented when the catgut was embedded to the trapezius, splenius capitis, semispinalis capitis, semipinalis cervicis and multifidus. But the distending pain was the most significant when in the myofascial. Commonly, the embedded catgut 2. 5 cm in length may be implanted deeply to the multifidus and the local needling sensation lasted averagely for (72. 0 ± 10. 2) h. Conclusion Under the ultrasound guidance, the depth of embedded catgut is clearly displayed at cervical Jiaji (EX-B 2). The needle insertion and the implanted material are visible, and the relationship between qi arrival and the layer of needle insertion is determined. The accuracy and safety of minimally invasive catgut embedding therapy is improved in the treatment of cervical spondylosis.