Objective: Through the anatomy study of the premasseter space, further improved the anatomic knowledge of the premasseter space and explored its application in rhytidectomy, in order to reduce the risk of facial nerve injury. To further improve the anatomic knowledge of the premasseter space and to determine its application in rhytidectomy. Methods: The anatomy of the premasseter region was investigated in 12 fresh cadaver (24 hemi-faces) dissections; 810 patients of SMAS rhytidectomy procedures were observed. Results: ①There were several soft tissue spaces superficial to the masseter muscle, and the boundaries were strengthened by retaining ligaments. Adjacent spaces were separated by numerous weak fiber membranes connecting the SMAS and masseter fascia. ②The space was further divided into two parts; one part was located under the platysma and another part was under the aponeurosis of SMAS. The former part was easier to identify and dissect.③The relaxation, expansion, and sliding of the space is an important reason in the face sags with aging, which is referred to as the layered ptosis theory. Conclusions The soft tissue space superficial to the masseter muscle have two different characteristics. The different nature of the two parts of the space can easily mislead dissection to the wrong layer, which is the important anatomical factors for the risk of facial nerve damage in rhytidectomy. The layered ptosis theory seem to better explain the process of aging.The primary treatment of aged face was facial space dissection and tighten.

Objective To explore the efficacy and safety of platelet-derived growth factor(PDGF)combined with allograft bone transplantation in the treatment of spinal tuberculosis.Methods A total of 177 patients with lumbar tuberculosis admitted to the 4th People's Hospital of Qinghai Province from August 2018 to August 2023 were selected as the research subjects.Patients were divided into control group(n=49)and observation group(n=128)based on the source of the transplanted bone.All patients underwent at least 2 weeks of standard quadruple anti-tuberculosis chemotherapy before surgery.Patients in the control group received PDGF combined with autograft bone transplantation,while patients in the observation group received PDGF combined with allograft bone transplantation.The surgical duration,intraoperative blood loss,and length of hospital stay of patients in the two groups were recorded;the erythrocyte sedimentation rate(ESR)and serum C-reactive protein(CRP)levels of patients in the two groups were compared before surgery and at 1,3,6 months after surgery.Preoperative CT and magnetic resonance imaging(MRI)examinations were performed,and postoperative CT and MRI were performed after bone fusion was completed to compare the changes in Cobb angle before and after surgery.The visual analogue scale(VAS)was used to assess the pain degree in the lumbar region before surgery and at 1,3,6 months after surgery.The VAS scores of patients in the two groups,VAS scores of male patients in the two groups,and VAS scores of female patients in the two groups were compared before and after surgery,respectively.Results There was no statistically significant difference in surgical duration and length of hospital stay between the observation group and the control group(P＞0.05).The intraoperative blood loss of patients in the observation group was significantly less than that in the control group(P＜0.05).There was no statistically significant difference in Cobb angle before and after surgery between the two groups(P＞0.05).The postoperative Cobb angle significantly decreased in both groups when compared to preoperative values(P＜0.05).The VAS scores of patients in both groups decreased sequentially before surgery and at 1,3,6 months after surgery,with statistically significant differences in intra-group pairwise comparisons(P＜0.05).The VAS scores of male patients in both groups decreased sequentially before surgery and at 1,3,6 months after surgery,with statistically significant differences in intra-group pairwise comparisons(P＜0.05).The VAS scores of female patients in both groups also decreased sequentially before surgery and at 1,3,6 months after surgery,with statistically significant differences in intra-group pairwise comparisons(P＜0.05).There was no statistically significant difference in VAS scores between the observation group and the control group before surgery and at 1,6 months after surgery(P＞0.05);the VAS score of patients in the observation group was significantly lower than that in the control group at 3 months after surgery(P＜0.05).There was no statistically significant difference in VAS scores between male patients in the observation group and male patients in the control group before surgery and at 1,3,6 months after surgery(P＞0.05);the VAS score of male patients in the observation group was significantly lower than that in the control group at 3 months after surgery(P＜0.05).There was no statistically significant difference in VAS scores between female patients in the observation group and female patients in the control group before surgery and at 1,6 months after surgery(P＞0.05);the VAS score of female patients in the observation group was significantly lower than that in the control group at 3 months after surgery(P＜0.05).The ESR of patients in both groups decreased sequentially before surgery and at 1,3,6 months after surgery,with statistically significant differences in intra-group pairwise comparisons(P＜0.05).The serum CRP levels of patients in both groups also decreased sequentially before surgery and at 1,3,6 months after surgery,with statistically significant differences in intra-group pairwise comparisons(P＜0.05).There was no statistically significant difference in ESR between the observation group and the control group before surgery and at 1,3,6 months after surgery(P＞0.05).There was no statistically significant difference in serum CRP level between the observation group and the control group before surgery and at 1,6 months after surgery(P＞0.05);the serum CRP level of patients in the observation group was significantly higher than that in the control group at 3 months after surgery(P＜0.05).Conclusion The effect of PDGF combined with allograft bone transplantation in the treatment of spinal tuberculosis is comparable to that of autograft bone transplantation,but PDGF combined with allograft bone transplantation can significantly reduce postoperative pain degree,improve patient comfort,avoid additional damage caused by autograft bone transplantation,and reduce the physical burden on patients.It can be considered a safe and reliable surgical method for bone grafting in lumbar tuberculosis surgery.