Postoperative Analgesic Effect of Infraspinatus-teres Minor Inter-fascial Block in Patients Undergoing Shoulder Surgery

Intersulcus brachial plexus nerve block is considered to be the best method for pain nerve block after shoulder joint surgery. It can not only effectively reduce the postoperative pain and discomfort of patients, but also reduce the intraoperative demand for opioids. However, the use of intermuscular brachial plexus block should be prohibited when the patient has a clotting disorder or is taking anticoagulant drugs, has a local infection or a systemic infection. There may also be anesthesia risks such as nerve damage, vascular damage, respiratory depression, and diaphragmatic paralysis with dyspnea.

Infraspinatus-teres minor (ITM), first proposed by Shin Hyung Kim, is a single-site injection in the interfascial plane between Infraspinatus and teres minor. Once the IS and Tm on the humeral head area are identified, by moving the probe mediocaudally, the interfascial structure of the IS and Tm can be traced along the glenohumeral joint, scapular neck area. On autopsy, local anesthetics were found to have spread to the suprascapular and axillary nerves. This result suggests that interfascia block injection of local anesthetics between the infraspinatus and teres minor muscles may help relieve pain in the upper shoulder, back, and external sensory areas. At present, there are few clinical reports on the use of infraspinatus-teres minor interfascial block for postoperative analgesia of shoulder joint, and the postoperative analgesia effect is only reported in individual cases, without comparison with other nerve blocks There are few studies on the clinical application of ITM block, but ISB has become the best method for postoperative analgesia of shoulder joint surgery. the investigators designed a prospective, randomized controlled, non-inferior study to investigate the efficacy of ultrasound-guided subaspina-teres minor interfascial block in analgesia and overall quality of recovery after shoulder joint surgery.

The primary outcome indicator was the area under the NRS curve at rest in the 0-24h postoperative period

Inclusion criteria

• Shoulder joint surgery in Jiaxing First Hospital from November 2023 to February 2024;
• Age 18-80 years old;
• ASA Grade I-III;
• The duration of surgery is expected to be 1-3h

Exclusion criteria

• accompanied by nerve injury or disease around the shoulder joint, including thoracic outlet syndrome, Multiple sclerosis, cervical disc disease with ipsilateral radiculopathy, etc.
• accompanied by abnormal sensory or motor function of the upper limb;
• Active infection at the puncture site, or coagulation dysfunction (hemophilia, von willeophilia, or International normalized ratio [INR]>2);
• Patients with severe respiratory diseases and a serious history of cardiovascular and cerebrovascular diseases;
• ipsilateral shoulder joint surgery history;
• Patients with nerve block failure;
• Allergic to local anesthetics;
• Long-term use of opioids (duration ≥3 months or duration ≥1 month and daily dose ≥5mg morphine equivalent);
• Operation time <1h or >3h
• Patients and their families refused surgical anesthesia and were unable to complete the questionnaire.