Fractures of the proximal humerus account for 5% of all fractures, and the incidence of comminuted fractures of the proximal humerus gradually increases with age, among which 71% of proximal humerus fractures occur in the elderly population over 60 years old. Except for conservative treatment for a small number of patients who cannot tolerate anesthesia, open reduction and internal fixation is still the first choice for treating displaced proximal humeral fractures. Affected by the fragile bone mass, elderly osteoporotic proximal humeral fractures of Neer type III-IV fractures are often accompanied by small fragments of metaphyseal comminuted. Most have metaphyseal compression or defect, which is extremely unstable and needs to be strengthened and rigid internal fixation. Still, due to the thin layer of cortical bone and sparse trabecular bone structure, the anchoring strength between internal fixation and bone is significantly reduced. Currently, the clinical treatment of this type of fracture often uses a single lateral plate fixation. Some scholars have reported that complications with a single locking plate are as high as 50%, and the related revision rate is about 15%. Complications include varus collapse, loss of reduction, screw penetration into the joint, internal fixation failure, subacromial impingement, and necrosis of the humeral head. Most scholars agree that repairing the medial structure, restoring metaphyseal support, and anatomically reducing nodules are the key to ensuring the therapeutic effect. Some studies have suggested that using a lateral plate combined with an allogeneic fibula or autologous ilium for intramedullary support can help resolve metaphyseal osteopenia and provide medical support for patients with osteoporosis, and achieve good clinical results. However, this method of bone implant fixation is limited by the source of the allogeneic bone, increased infection rate, disease transmission, immune rejection, complications in the donor site of autologous bone, etc., and has not been widely used clinically.

To investigate the feasibility and efficacy of PHILOS plate combined with individualized intramedullary anatomical bone cement placeholder in treating elderly osteoporotic proximal humeral fractures.

Retrospective analysis was made on 38 cases of elderly osteoporotic proximal humeral fractures treated in our hospital from January 2020 to June 2021. According to the different fixation methods, they were divided into two groups: the PHILOS plate combined with individualized intramedullary anatomical bone cement placeholder group (group A, 18 cases) and the PHILOS plate alone group (group B, 20 cases) . The operation time, intraoperative blood loss, incision drainage volume 48 hours after the operation, fracture healing time Follow up imaging data (loss amount of neck shaft angle, humeral head varus angle, loss amount of humeral head height) , Constant Murley scores of the shoulder (CMS) and total complications.

All 38 patients were followed up after the operation. There was no significant difference between the two groups regarding the operation time, intraoperative bleeding volume, incision drainage volume 48 hours after the operation, and fracture healing time (P>0.05) . Still, the loss of neck shaft angle, humeral head varus angle, humeral height loss, CMS score, and the incidence of total complications after the operation were better in group A than in group B (P<0.05) .

The clinical effect of PHILOS plate combined with individualized intramedullary anatomical bone cement placeholder in treating elderly osteoporotic proximal humeral fracture is better than that of internal fixation with Philips plate alone. It has the advantages of high fixation strength, sound reduction and maintenance, high functional score, and fewer complications. It is a reliable method for treating an elderly osteoporotic proximal humeral fracture.