[Application and research progress of dexamethasone in the perioperative period of joint arthroplasty and arthroscopic surgery].

Objective: To review the application and research progress of dexamethasone in the perioperative period of joint arthroplasty and arthroscopic surgery. Methods: The relevant domestic and foreign literature in recent years was extensively reviewed. The application status and therapeutic effect of dexamethasone in the perioperative period of joint arthroplasty and arthroscopic surgery were summarized. Results: Studies have shown that intravenous administration of 10-24 mg dexamethasone before or/and within 24-48 hours after operation can reduce the incidence of nausea and vomiting, and reduce the consumption of opioids in patients after hip and knee arthroplasties with high safety. The duration of nerve block during arthroscopic surgery can be prolonged by perineural injecting local anesthetics and 4-8 mg dexamethasone, but the effect of postoperative analgesia is still controversial. Conclusion: Dexamethasone is widely used in joint and sports medicine. It has the effects of analgesia, antiemetic, and prolonging the time of nerve block. In the future, high-quality clinical studies on the application of dexamethasone in shoulder, elbow, and ankle arthroplasties and arthroscopic surgery are needed, and more attention should be paid to the long-term safety of dexamethasone.

[Research progress of anterior cutaneous nerve injury and repair in knee arthroplasty].

Objective: To summarize the research progress of anterior cutaneous nerve injury and repair in knee arthroplasty. Methods: The relevant literature at home and abroad in recent years was reviewed and summarized from the anatomy of anterior cutaneous nerve, nerve injury grade, clinical manifestations, prevention and treatment of anterior cutaneous nerve. Results: The anterior cutaneous nerve injury is a common complication of knee arthroplasty. Because the anterior cutaneous nerve branches are many and thin, and mainly run between the first and second layers of fascia, this level is often ignored during surgical exposure. In addition, the knee arthroplasty does not routinely perform the exploration and repair of the cutaneous nerve. So the anterior cutaneous nerve injury is difficult to avoid, and can lead to postoperative skin numbness and knee pain. At present, studies have explored the feasibility of preventing its occurrence from the aspects of improved incision and intraoperative separation of protective nerve. There is no effective prevention and treatment measures for this complication. For patients with skin numbness after knee arthroplasty, the effectiveness of drug treatment is not clear. Local nerve block or nerve excision can be used to treat patients with painful symptoms after knee arthroplasty considering cutaneous pseudoneuroma. Conclusion: Knee arthroplasty is widely used and anterior cutaneous nerve injury is common in clinic. In the future, more high-quality clinical studies are needed to further explore the prevention and treatment measures of this complication and evaluate the clinical benefits obtained.

[Analysis of the influence of tibial component posterior slope angle on short- and mid-term effectiveness of unicompartmental knee arthroplasty].

OBJECTIVE: To investigate the influence of tibial component posterior slope angle (TCPSA) on the short- and mid-term effectiveness of unicompartmental knee arthroplasty (UKA). METHODS: The clinical data of the patients with anterior medial knee osteoarthritis (KOA) treated by UKA between May 2014 and May 2019 were retrospectively analysed. There were 10 males and 45 females with a median age of 68 years (range, 49-83 years). The body mass index (BMI) was 27.63-52.26 kg/m 2, with an average of 40.04 kg/m 2. There were 28 cases of left knee, 21 cases of right knee, and 6 cases of double knees. The disease duration was from 7 months to 12 years, with an average of 4.33 years. Measurements of posterior tibial slope (PTS) and TCPSA were performed on the knee joint X-ray films of patients before operation and at last follow-up, respectively. According to the postoperative TCPSA, patients were divided into TCPSA<4° group (group A), 4°≤TCPSA<9° group (group B), and TCPSA>9° group (group C) with the quartile method. Baseline data such as age, gender, BMI, and affected side were compared among the 3 groups, as well as the Hospital for Special Surgery (HSS) score, visual analogue scale (VAS) score, and range of motion (ROM) before and after operation. RESULTS: All 55 patients were followed up 17-72 months, with an average of 36 months. No complication such as prosthesis loosening, infection, tibial plateau collapse, and dislocation of the meniscus pad occurred. The preoperative PTS was (7.38±3.37)°, and the postoperative TCPSA was (6.25±3.22)°, showing no significant difference ( t=1.815, P=0.074). According to postoperative TCPSA, there were 12 knees in group A, 32 in group B, and 17 in group C. There was no significant difference in age, gender, BMI, affected side, and preoperative HSS scores, ROM, and VAS scores among the 3 groups ( P>0.05). At last follow-up, the HSS scores, ROM, and VAS scores of the 3 groups significantly improved when compared with preoperative ones ( P<0.05). There was no significant difference in the difference of the above indicators before and after operation among 3 groups ( P>0.05). CONCLUSION: The patients with anterior medial KOA may have good short- and mid-term effectiveness after UKA. Among the recommended range of TCPSA, there is no significant influence on the postoperative short- and mid-term effectiveness. Long-term effectiveness need to extend the follow-up time and expand the sample size for research verification.