Causes of rotator cuff tears include trauma, degeneration and infection, and it is a common cause of shoulder pain and dysfunction. It is prevalent in adults over the age of 45. Treatment options include conservative treatment, incision repair, small incision incision repair, and total arthroscopic repair. Indications for arthroscopic repair include symptomatic rotator cuff tears (pain and dysfunction), large non-repairable rotator cuff tears, but other factors such as the patient’s ability to tolerate the surgery, the patient’s demands and expectations, the surgeon’s assessment of the functional recovery after the surgery, and the presence or absence of coexisting osteoarthritis or significant upward displacement of the humeral head must also be considered. Contraindications to arthroscopic repair include active infection, permanent innervation loss, and severe osteoarthritis of the glenohumeral joint. Relative contraindications include poor or unpredictable prognosis after repair, severe atrophic fatigue of the supraspinatus and infraspinatus muscles <75%, patient's inability to cooperate with postoperative rehabilitation, and significant displacement of the humeral head with bony changes on imaging. The position for surgery can be chosen from the beach chair position to the lateral position according to personal preference, with traction weights of approximately 5-10 pounds in lateral traction, 40° of abduction and 20° of forward flexion of the affected limb, and heated blankets are applied as much as possible during the operation to prevent hypothermia from occurring. Anesthesia can be provided by interosseous anesthesia, general anesthesia, or a combination of the two. The use of interosseous anesthesia alone is only indicated for patients with a short operative time and good general condition. If the operation time is long, the patient may have obvious neck edema during the operation, which may cause respiratory insufficiency, and the blood pressure needs to be controlled between 90-110 mmHg during the operation, general anesthesia is recommended. In addition to the conventional arthroscopic system, grinding drill, planer, radiofrequency, there is also a need to have a water injection and pressurization pump system during the operation, the water injection pressure should be controlled at 50-70mmHg, and the operation time should be controlled at less than 2 hours, so as to avoid the excessive edema of the tissues. In addition, there should be a variety of angles of the over-the-wire device can be selected and used, and now each company has its own characteristics of the over-the-wire device to choose from, such as Arthrex's BirdBeak, Scorpion over-the-wire, Viper over-the-wire, etc. Linvatec's suture hooks, Depuy Mitek's, and, in addition, the operation of a good helper is very important. There are various types of suture anchors available, metal, plastic, absorbable, and of different diameters and sizes depending on the site, the quality of the bone and the size of the space. The pullout strengths of the anchors vary considerably depending on the design of the anchor. The pullout strengths of several anchors tested by Barber in 2003 within the metaphyseal cortex were as follows: Twinfix AB 485 N, Twinfix Ti 5.0 448 N, BioCorkscrew 5.0 222 N, and BioCorkscrew 6.5 181 N. Suture anchors The sutures used have also evolved significantly this year, from the Axiomtek sutures of the past to Fiberwire, MaxBraid, Orthocord, UltraBraid, etc. The tensile strength of sutures of the same diameter has almost doubled, and the incidence of failed rotator cuff repairs caused by suture breakage has become less and less likely. In addition, the arthroscopic knotting technique also affects the strength of the rotator cuff fixation after surgery. The choice of suture method, we commonly use simple suture, mattress suture, edge suture, microscopic Mason Allen, etc. In vitro biomechanical test results showed that the tensile strength of mattress suture was 228 N, while the modified Mason-Allen method was 168 N. In terms of fixation, the microscopic suture was gradually developed from single-row suture fixation to double-row fixation, and even triple-row fixation was proposed. Even three-row fixation has been proposed. Double-row fixation can increase the contact area of the tendon bone and contact pressure, which can promote healing, but the literature reports on the effect of different methods are different. Most retrospective studies have reported no significant difference in clinical outcomes between single-row and double-row fixation. A prospective randomized study showed no clinical difference between 40 single-row and 40 double-row cases (Andre G, Arthroscopy 2008, Italy). A biomechanical study tested double-row fixation until 5000 cycles without failure, whereas single-row fixation withstood only 798.3 ± 73.28 cycles (Steven W. MeierArthroscopy 2006). A study of rotator cuff footprint coverage showed that 52.7% of single-row fixations were not covered, whereas double-row fixations could achieve complete coverage (Paul C. BradyArthroscopy 2006). Single-row fixation is currently recommended for partial or small tears, and double-row fixation is recommended for large tears Arthroscopic release is a very important step in the surgical maneuver, especially for microscopic repairs of large rotator cuffs, where adequate release is necessary, and rostral apical plication should be considered if the distance between the tip of the rostral eminence and the subscapularis muscle is less than 7 mm. It is still controversial whether acromioplasty must be performed on the acromion. Acromioplasty weakens the deltoid stop and creates a scar between the subacromial bone trauma and the repaired rotator cuff; however, if there is a definite hyperplasia of the acromion, bony redundancy, or subacromial impingement, acromioplasty should be performed at the same time. A number of factors influence healing after rotator cuff repair, such as the angle and depth of suture anchor implantation; if the angle of camber is too small and the depth is too deep, the suture anchors are prone to be pulled out and loosened. Adequate intraoperative loosening of adhesions reduces post-suture tendon tension. Adequate preparation of the tendon-bone interface (clearing the tendon edges, preparing the bone bed to bleed, etc.) also promotes healing. The use of different sutures to increase the tendon-bone contact area and pressure, as well as relatively conservative postoperative rehabilitation, will promote tendon-bone healing of the rotator cuff and thus reduce the failure rate.