Proximal humeral fractures are currently a common fracture [8–9], and lateral locking plate fixation is currently the most widely used surgical method for the treatment of proximal humeral fractures .However, as time goes by, more and more scholars have found that the postoperative complications of the treatment of complex proximal humeral fractures with lateral locking plates are still high, such as: humeral head varus deformity, fracture displacement, internal Loose fixation, broken screws, etc. .The anteromedial support plate assisted reduction technique used in this study has certain advantages in maintaining the reduction of proximal humeral fractures and reducing postoperative complications.The anterior medial plate of the intertubular groove can provide an effective medial stress dispersion for the treatment of proximal humeral fractures, so that the humeral head can obtain effective biological support, thereby increasing the stability of fracture reduction and reducing the loss of fracture reduction.According to the study of Wu JW et al. , patients with medial support are better than patients without medial support in terms of humeral head height loss, indicating that restoring medial support can maintain the reduction effect and enhance the stability of reduction.Karppinger et al.  proved through biomechanical studies that those with support on the inner side of the proximal humerus can increase the axial load by nearly 10 times compared with those without support. It also explains the importance of medial support for maintaining fracture reduction.In addition, this research has improved the traditional double steel plate technology. The traditional double steel plate technology is to reset first, and then place the double steel plate for fixation. In this research, the support plate is placed on the anterior and medial side of the internodal groove first, and then depends on the stable medial support. Perform reduction and fixation, which reduces the difficulty of fracture reduction.
The anterior and posterior humeral arteries are the main blood supply source of the proximal humerus, and the survival of the ascending branch of the anterior humeral artery after the fracture directly affects the occurrence of avascular necrosis of the humeral head .Therefore, we need to be especially careful when performing medial reduction and fixation of proximal humeral fractures to protect the medial soft tissues and important blood vessels and nerves.The traditional double plate fixation technique is to place the medial support plate on the inner side of the biceps long head tendon groove. Excessive dissection will inevitably destroy a part of the medial blood supply, and we place the medial plate on the long biceps brachii. The anterior and inner side of the cephalic tendon groove only needs to peel off the partial stop of the pectoralis major muscle, which can better protect the blood supply of the humeral head.
In this study, based on the original lateral locking plate, a pre-curved 1/3 tube-shaped plate was added to the inner side of the proximal humerus during the operation to assist the reduction of complex proximal humeral fractures and enhance the stability of the fracture reduction. At the same time observe its clinical efficacy.In this study, although the surgical procedure required to place two plates in the study group was more complicated than that in the control group, the study group placed a support plate on the medial side to restore the stability of the medial column, simplify the operation, and reduce the loss of position after bone block reduction. It can reduce the number of effective intraoperative fluoroscopy, and complete the reduction and fixation of fractures with better and higher quality.Therefore, there was no statistical difference in the length of operation and the amount of bleeding between the two groups. Park SG et al.  also demonstrated this view.At the same time, this also reduces the radiation exposure of the surgeon and the patient during the operation. With the continuous improvement of surgical skills and proficiency, the operation time and blood loss of the use of internal and external double plate treatments will also be reduced.Comparing the loss angle of the humeral neck shaft angle of the two groups after reduction, although there was no significant difference between the two at the first and third months, at the sixth and 12th months, the data of the control group showed higher data and statistics Learn the difference.This shows that the study group has a greater advantage in maintaining the long-term stability of complex proximal humeral fractures after reduction and fixation than the control group. It can also be further inferred that the study group's complications such as humeral head deformity will be less than the control group.Theopold J and others have also reached a similar conclusion.According to Liu ZD  and others, when the humeral neck shaft angle is less than 120° after reduction, it will have an impact on the recovery of shoulder joint function.Therefore, we regard the neck-stem angle <120° after reduction as meaningful or as the loss of neck-stem angle reduction.In this study, the loss of reduction rate in the control group reached 14.5%, while in the study group, there was no obvious loss of reduction.This further shows that the research group has certain advantages in maintaining stability after reset.Regarding the shoulder joint Constant score and the upper limb function DASH score, although the study group’s re-examination scores at each time point were higher than those of the control group, the difference between the two was not statistically significant. The shoulder joint function of the two groups of patients was All had a relatively good recovery after the operation.The possible reason for the small difference in functional scores between the two groups is that we conducted a careful evaluation before the operation and selected the corresponding surgical methods according to different situations, so that the patients can get good treatment.Although there was a difference in the angle loss of the neck-stem angle between the two groups, there was no loss of more than 20°, so there was no significant difference in the recovery of shoulder joint function between the two groups.For complex proximal humeral fractures, especially fractures with medial column injuries, if the support of the medial column cannot be effectively restored during the operation, it will inevitably increase the secondary varus collapse, loss of reduction and final fixation failure of the humeral head due to lack of support. The possibility .In this case, only one lateral steel plate cannot effectively maintain the stability of the fracture. Therefore, it is often necessary to use the medial steel plate for the necessary auxiliary support to rebuild the stability of the medial column, and cooperate with the lateral locking plate to complete the reduction and fixation of the fracture .The main reason for the use of double plate fixation is that the use of a single lateral locking plate cannot recover and maintain the support of the medial metaphysis to the humeral head due to various reasons during the operation.Therefore, this technology cannot be used as a commonly used clinical fixation technology, and its application indications should be strictly controlled:1. The medial metaphysis is damaged, and the bone quality is poor, which is expected to be difficult to restore and fix.2. It is easy to shift after reset and fixation, and the internal fixation fails.3. After reduction and fixation, humeral head varus collapse or head and neck separation is likely to occur.In addition, we recommend that a lot of study and observation should be done before using this technique to prevent invalid fixation due to lack of surgical skills and experience.
In this study, there was 1 case of incision fat liquefaction in the control group.The patient is a 67-year-old obese elderly woman,Surgery was performed on the 10th day after injury,The dressing was found to be moist on the 7th day after surgery,Pressing the incision has yellow exudate, the incision has no redness and swelling, and the skin temperature is not high. It is considered that the fat is liquefied.Our analysis may be due to the thick subcutaneous fat of the patient, the high temperature generated during the operation of the electrosurgical knife that damaged the adipose tissue, and the excessive stretching of the adipose tissue during the fracture reduction.Therefore, for obese patients, it is especially necessary to pay attention to the gentle operation during the operation and avoid excessive use of electric knife to cut fat tissue.One case of axillary nerve palsy occurred in the study group. Considering that it was caused by excessive pulling of the upper extremity in the external rotation position for a long time during the process of fracture reduction and plate placement.During the operation, it is necessary to pay attention to the gentle reduction movement, improve the surgical technique, and strengthen the protection of the axillary nerve.
This study has several limitations.First of all, this article is a retrospective study based on the results of follow-up, so the differences in observations may bias the study.Second, the sample size of this study is small, the follow-up time is short, and the sample statistics need to be expanded for long-term research.