Metatarsal tendinitis is the most common cause of heel pain. The metatarsal tendon membrane is a superficial portion of the plantar fascia that serves to protect plantar tissues, provide attachment points for certain intrinsic plantar muscles, and assist in maintaining the arch of the foot. The exact etiology of metatarsal tendonitis is not well understood, and the cause may be related to a tiny tear at the beginning of the metatarsal tendon caused by the metatarsal tendon membrane pulling on the heel tuberosity during walking, osteochondritis, and fatigue fractures of the medial heel tuberosity. The disease is most common in obese middle-aged women and those who like to exercise. The main manifestation is pain on the metatarsal side of the heel bone, which is worse after the first few steps of walking in the early morning, partially relieved by further activity, and then aggravated by prolonged activity. “Although there are many treatment methods, including weight reduction, pulling exercise, physiotherapy and closure, there are still a considerable number of patients with long-term pain, which brings great difficulties to life and work. In the early 1990s, Extracorporeal Shock Wave Therapy ESWTwas used abroad for the treatment of metatarsal tenosynovitis, and achieved better clinical results. From January to June 2002, our department used the Israeli orthopedic extracorporeal shock wave therapy device to treat metatarsal tendonitis and achieved good results. From September 2006 to February 2009, our foot and ankle surgery department applied the radiation shock wave therapy instrument produced by Swiss DOLORCLAST to treat 110 cases of 150 foot metatarsal tendonitis patients, and the results are summarized here. 1. Data and methods 1 .1 General data There were 110 patients in this group, 38 men and 72 women, aged 23-75 years old, with an average of 49 years old. There were 75 left feet, 55 right feet, 10 bipedal, total 150 feet. The duration of disease: 21 patients were under 3 months, 30 patients were 3-6 months, 28 patients were 6-12 months, 20 patients were 12-24 months, and 11 patients were over 24 months. 54 patients had no other treatment, 46 patients had non-surgical treatment such as herbal foot soak, physiotherapy, massage, closure, pain medication and pulling exercise, and 10 patients had small needle knife treatment. All treated patients had no infected lesions on their feet, no history of trauma, and no heart attack or cerebral hemorrhage within 6 months. 1.2 Treatment equipment The treatment instrument was a radiation shock wave treatment instrument manufactured by DOLORCLAST, Switzerland. 1.3 Treatment method After the affected foot is cleaned, the foot is coated with coupling agent, and the shock wave focus is aimed at the most obvious pressure pain at the proximal end of the plantar tendon. For the first treatment, the treatment pressure is 2.0Bar-3.5Bar frequency varies from 4-8HZ, the handle pressure is moderate to severe, 2000 strokes are performed, and the treatment time is 5-10 minutes. Once a week treatment, generally need 4 times treatment, can be extended according to the condition of 2-4 times, up to 8 times . 2.Efficacy assessment method: The pain was assessed before and after treatment according to VAS (visual analog scale). Pain assessment: pain assessment before treatment – pain assessment after treatment >1 is excellent, =1 is good, =0 or <1 is poor. Motor function assessment: motor function was divided into 4 degrees according to the patient's activity: degree 1: normal activity; degree 2: slight activity: able to do daily activities, but cannot walk or stand for more than 1 hour; degree 3: severely limited activity; degree 4: completely inactive, the patient cannot walk or stand continuously for more than 5 minutes. Pre-treatment motor function assessment - post-treatment motor function assessment >1 is excellent, =1 is good, =0 or <1 is poor. 3, results Follow-up of all treated patients, follow-up time 10-20 months. 110 people 150 feet, only received 1 treatment 15 feet, pain assessment excellent 5 feet, good 4 feet, poor 6 feet, motor function assessment, good 9 feet, poor 6 feet; 2 treatment 40 feet, pain assessment excellent 7 feet, good 20 feet, poor 13 feet, motor function assessment excellent 8 feet, good 25 feet, poor 7 feet; 3 treatment 35 feet, pain assessment excellent 25 feet, good 25 feet, poor 7 feet. The pain assessment was excellent 25 feet, good 8 feet, poor 2 feet, motor function assessment was excellent 23 feet, good 9 feet, poor 3 feet; 4 times treatment 50 feet, pain assessment was excellent 37 feet, good 13 feet, motor function assessment was excellent 41 feet, good 9 feet; 5 times treatment 6 feet, pain assessment was excellent 5 feet, good 1 foot, motor function assessment was excellent 4 feet, good 2 feet; 8 times treatment 4 feet, pain assessment was good 2 feet, motor function assessment was good 2 feet. The patients in this group had good pain and good motor function. After treatment, a few patients in this group can feel pain aggravation or no pain relief for a short period of time, and the symptoms will improve after continuing treatment, without other adverse reactions. 4, Discussion The plantar tendon membrane, also known as the plantar tendon membrane, is located on the bottom of the foot as the arch chord, and is a thickened part of the deep fascia of the foot, divided into the middle bundle and the medial and lateral bundles, which plays an important role in maintaining the longitudinal arch of the foot and cushioning shock. In addition, it has the function of protecting the plantar muscles and foot joints. During the gait cycle, it assists in maintaining the posterior rotation of the subtalar joint and is an important structure for maintaining normal foot function. "When the foot is under weight, the metatarsal tendon membrane is stressed by the need to maintain the longitudinal arch of the foot, which can cause strain and irritation at the heel stop. The exact cause of metatarsal tenosynovitis is not well understood. Clinically, metatarsal tenosynovitis has been found to be more common in obese middle-aged women and those who are athletic, with soft-soled shoes and excessive exercise also being a contributing factor. Other conditions, such as heel exostosis, foot rotation deformity, and changes in the arch of the foot after degeneration of the tendons and ligaments in middle-aged and elderly people, will subject the metatarsal tendon membrane to greater stress, and the long-term chronic strain can cause small tears in the local tendon membrane and local edema to produce inflammation. "Berkowitz compared the thickness of the proximal metatarsal tendon membrane between normal subjects and patients with chronic heel pain by MRI and found that the latter had an increase of 4.4 mm compared to the former. Pathological examination of the proximal metatarsal tendon membrane also revealed collagen necrosis, fibrovascular hyperplasia, chondrogenesis and matrix calcification. This pathologic change is similar to that seen at the radial extensor hallucis muscle stop in patients with tennis elbow, which has also been described as "tennis heel" in proximal plantar tendinitis. "Most patients with proximal plantar tenosynovitis can have their symptoms relieved through non-surgical treatment. Commonly used non-surgical treatments include physical therapy, anti-inflammatory and analgesic drugs, foot pads, stretching exercises for the plantar tendon membrane and Achilles tendon, night brace immobilization, and stimulation and closure therapy. However, there is no one non-surgical treatment method with definite efficacy, and several methods are generally used in combination in clinical practice. Closure therapy can relieve pain more effectively, but repeated closure may cause rupture of the metatarsal tendon membrane. Despite various non-surgical treatments, some patients may have persistent symptoms, sometimes requiring partial surgical severance of the plantar tendon membrane. Surgery does not relieve pain in all patients and there is a risk of complications. "The reason for the high failure rate of one treatment may be that some patients give up treatment after one treatment without significant effect. 4 treatments may significantly improve the effect. However, the number of treatments increased again on this basis and the efficacy did not increase significantly. Therefore, it is recommended that patients have a course of 4 treatments, which can be extended appropriately for 2-4 times, and if the pain does not improve significantly, it is not recommended to continue to increase the treatment. Shock wave will have individual side effects such as petechiae and hematomas during the treatment, and the side effects need to disappear before continuing with the next treatment. The principle of this shock wave treatment lies in the fact that after the shock wave acts on the painful area, it promotes the release of a vasoactive substance called substance P, which provides pain relief; on the other hand, it can promote vasodilation and enhance collagen synthesis, which helps the recovery of tendons. The shock wave also inhibits the release of activating mediators, activates cellular protection, and enhances the stimulation of nerve fibers to resist pain, enhance pain relief, and promote tissue regeneration. Therefore, this treatment method is safe, has no side effects, and can be used when other non-surgical treatments are ineffective. This shock wave therapy instrument starts from the highest energy that the patient can tolerate the degree of treatment, but some patients will have a significant increase in pain during the treatment, which usually does not require local anesthesia, and the energy can be reduced appropriately, and then the energy can be increased after the pain is relieved. The follow-up time of this group of patients is relatively short, and the medium- and long-term efficacy needs to continue to be observed, but as a new method that is non-invasive, safe and has few complications, it is worth further research and promotion.