OBJECTIVE: To compare the clinical efficacy of locking plate and multiple pin internal fixation for proximal humeral fractures and to analyze the characteristics of the two internal fixation techniques. Methods From February 2007 to March 2009, 23 cases of proximal humerus fractures were treated by prospective study of internal fixation, including 16 males and 7 females, with an average age of 49.5 years. The patients were randomly divided into two groups: group A used the locking plate internal fixation technique, with 11 cases; group B applied the multiple pin internal fixation technique, with 12 cases. The results in terms of operative time, intraoperative X-ray exposure time, fracture healing time and postoperative functional excellence rate were compared among the patients.
The mean operative time was 83.5 min, including 75.3 min in group A and 91.6 min in group B. Compared with group A, the difference between group B was statistically significant in terms of operative time, X-ray exposure time, and postoperative functional excellence rate (P < 0.05), while the difference between the two groups in terms of fracture healing time was not statistically significant (P > 0.05). All fractures healed after 3 to 18 months (mean 12.5 months) of postoperative follow-up. CONCLUSION: Internal fixation is an effective method for treating proximal humeral fractures, and the application of a locking plate has a more satisfactory effect in shortening the operative time, reducing the time of X-ray fluoroscopy, and recovering function after surgery than the application of multiple pins for internal fixation of proximal humeral fractures.
Humerus; fracture; internal fixation; Clinostat pin; locking plate
Proximal humerus fracture is a common clinical injury, accounting for 4%-5% of all fractures in the body, and the fracture site is close to the shoulder joint, so the treatment outcome is often demanding. The techniques of closed reduction and internal fixation with multiple Clinique pins and incisional reduction and locking plate are commonly used to treat proximal humerus fractures. Our hospital admitted and internally fixed 23 patients with proximal humerus fractures from February 2007 to March 2009, respectively, using the above two internal fixation methods, and the retrospective analysis is summarized as follows.
I. Data and methods
(1) General information. There were 23 cases in this group, 16 males and 7 females, all with fresh closed fractures, aged from 23 to 79 years old, with an average of 49.5 years old. All patients routinely underwent orthopantomographies, CT scans and 3D reconstructions of the shoulder joint, and the fractures were classified according to the imaging data. The fractures were classified according to Neer’s classification: 12 cases of type II, 9 cases of type III, and 3 cases of type IV. The time from injury to surgery ranged from 1 to 12 d, with an average of 3.6 d.
(2) Surgical methods Surgery was performed under brachial plexus or general anesthesia.
①LCP group
The fracture was repositioned by traction under direct visualization and temporarily fixed with a Kirschner pin, and a C-arm fluoroscopy was performed to determine that the fracture was satisfactorily repositioned and then a suitable length was placed on the lateral humerus. The locking plate was placed on the lateral side of the humerus at a height not exceeding the greater tuberosity to avoid impingement syndrome. 3 to 6 locking nails were screwed into the proximal end of the fracture towards the humeral head, and the locking tip was confirmed under fluoroscopy not to exceed the humeral head. The affected limb was protected by a forearm sling after surgery, and the drainage tube was removed at 24~48 h. Passive functional exercise of the shoulder joint was performed on the third postoperative day, and the shoulder joint activity was strived to reach or approach the normal range within 2 weeks.
②Knuckle needle group
After satisfactory repositioning by X-ray fluoroscopy, the assistant maintained the alignment, and the operator fixed the fracture end percutaneously with a Kirschner needle, avoiding penetrating the humeral head, and the needle penetration site was mostly located at the anterior, anterolateral, and lateral sides of the proximal humerus, and the direction was mostly superior to inferior and inferior to superior. After the internal fixation was confirmed to be in place and reliable, the end of the needle was bent and left outside the skin and wrapped, and passive and active functional exercises of the shoulder joint were performed after 3~4 weeks of plaster-assisted external fixation.
(3) Statistical methods
The operation time and X-ray fluoroscopy time were recorded intraoperatively, and the fracture healing time and excellent functional recovery rate were recorded postoperatively. SPSS11.0 software was used for statistical analysis of the results, and t-test was used for scoring, and P < 0.05 was considered statistically significant difference.
2, Results
The 23 patients received 3 to 18 months (mean 12.5 months) of follow-up. All fractures healed (healing time 6 to 13 weeks, mean 9 weeks). There were no incision infections and one case of ischemic necrosis of the humeral head, but the function of the shoulder joint was satisfactory. one case of retraction of the gristle pin did not affect the fracture position or fracture healing. The Neer score was used for postoperative functional assessment.
3. Discussion
The aim of treatment of proximal humeral fracture is to restore a pain-free shoulder joint with normal or near-normal range of motion [1].Since the proximal humeral fracture is crushed after injury, resulting in a complex fracture, the thin bone cortex cannot provide firm support for internal fixation, followed by failure of internal fixation of the fracture with delayed healing and shoulder stiffness [2], the choice of internal fixation is very important, and most scholars believe that if it can be stable fixation, the intraoperative damage to the fracture blood flow is small, and the affected limb can perform functional exercises early after surgery, the postoperative humeral head necrosis rate will be reduced, and the functional recovery of the shoulder joint will be back better [3]. The application of internal fixation with a Kristen pin for the treatment of proximal humeral fractures has a long history, and Resch et al. reported that percutaneous needle penetration provided a more stable fixation approach. With the advances in surgical techniques, the advent of the proximal humeral locking plate has certainly provided a more stable fixation approach for proximal humeral fractures.
The results of previous cases of conservative treatment and fixation failure with deformed fracture healing suggest us that internal fixation should be performed to ensure alignment and minimize damage to the internal environment of the fracture to avoid adverse effects on healing, and our internal fixation follows this principle. The results of a comparative study of proximal humeral fractures treated with LCP and kerf pins suggest that there is no significant difference in fracture healing rate at 8 weeks postoperatively, and that operative time, x-ray exposure time and functional recovery were significantly superior to LCP.
Advantages of LCP technique.
1. The locking screw has the role of internal fixation frame and has strong holding capacity for the fracture.
2. The nail hole design of LCP has two functions: stable fixation or power compression, which facilitates fracture repositioning and does not cause loss of repositioning [4].
3, The plate edge suture hole is conducive to one-stage repair of rotator cuff injury, which is beneficial to the functional recovery of the shoulder joint [5].
4, There is a potential gap between the LCP and the bone cortex, which has less pressure on the periosteum, which is conducive to the growth of trophoblastic vessels and the restoration of blood flow to the fracture end, thus facilitating fracture healing.
LillH et al [6] showed that LPHP has minimal loss of fixation strength and better fixation effect than other fixation methods in cancellous bone specimens.Plecko et al [7] clinically analyzed the efficacy of LPHP internal fixation in 64 patients with proximal humerus fractures. The analysis showed that the functional recovery of the shoulder joint was good.
Closed reduction internal fixation with a Kirschner pin has the advantage of being less invasive, but because closed reduction x-ray fluoroscopy often takes longer to satisfactorily reposition the fracture and intraoperative adjustment of the Kirschner pin internal fixation position is often required, there is no significant advantage in operative time, instead receiving significantly longer x-ray exposure than LPHP internal fixation. Due to the non-strength of the Kirschner pin fixation, plaster-assisted external fixation is required for 3 weeks after surgery, thus leading to shoulder stiffness, which is contrary to the principle of early functional exercise after internal fracture fixation and ultimately leads to unsatisfactory recovery of joint function.
The choice of treatment method for proximal humerus fracture depends to a certain extent on the surgeon’s own experience and ability, and often the operator subjectively chooses a familiar surgical approach.
Using LPHP internal fixation we summarize the following experiences.
1, the commonly used deltoid and pectoralis major muscle gap approach is simple to operate, but the alignment of the fracture can be better observed during the repositioning.
2, Two 2.0mm kerf pins can be used as skid rods or temporary repositioning fixation during intraoperative repositioning, which is very helpful for repositioning, and C-arm fluoroscopy after repositioning ensures the repositioning effect.
3.For elderly patients with osteoporosis and bone defects, bone grafting after fixation is recommended.
4. Postoperative functional exercise plays an extremely important role in the recovery of shoulder function. On the first postoperative day, immediately after pain relief, perform functional exercise of the shoulder joint and gradually increase the range of motion, aiming for the shoulder joint range of motion to reach or approach normal joint function 2 weeks after surgery.
Although both internal fixation methods are effective, LPHP has the advantage of shorter X-ray exposure time and significantly better postoperative shoulder function than kyphotic pin internal fixation.