Currently, the distal clavicle locking plate can achieve better results and is widely used compared to clavicular hook plate in the treatment of distal clavicle fractures Neer type II fractures. For Neer type IIb fractures, whether to reconstruct the coracoclavicular ligament does not have a broad consensus. In order to explore its significance and necessity, from July 2013 to December 2016, single distal clavicular anatomical locking plate or plate combined with suture anchor were respectively used in the treatment of distal clavicular fractures of Neer type IIb for comparison.

To explore the necessity and significance of the functional reconstruction of the coracoclavicular ligament in NeerⅡb distal clavicle fractures treated with anatomical locked plate.

General information:The complete follow-up records of 41 patients (26 males and 15 females) with Neer type IIb distal clavicular fractures were collected. Postoperative follow-ups were conducted until the radiographs showed fracture healing from 8 months to 26 months. The ages ranged from 19 to 69 years old with an average of 47 years. The causes of injury included traffic accidents, fall damages and high falling injuries. All the fractures were fresh. The time from admission to operation was 1 to 7 days with an average of 3.6 days. The clavicular anatomical locking plate group had 21 cases and the combined suture anchor group had 20 cases. The preoperative general data between two groups had no statistical difference (P>0.05) with comparability. Operative methods: (1) Distal clavicular anatomical locking plate group:After satisfactory brachial plexus block of interscalene approach or general anesthesia, the patient was placed in beach chair position with pad below the ipsilateral scapula. As the operative region was routinely disinfected and draped, a transverse incision (or an incision along Langer's line) along the direction of clavicle was made from its lateral side. The skin and subcutaneous tissue were incised layer by layer, and the muscles were separated to reveal the fracture ends that were restrictively dissected with periosteum exfoliator. The hematoma at fracture ends and embedded soft tissue were debrided, and a Kirschner wire was used for oblique fixation after fracture reduction. A distal clavicular locking plate of proper length was selected and placed above the front of clavicle. After drilling, depth measurement and tapping, 4-6 screws were inserted into the distal clavicle and 3-4 screws were inserted into the proximal clavicle. Passive activities were performed to check the stability of fracture. The incision was sutured layer by layer after hemostasis and irrigation. (2) Joint application of clavicular anatomical locking plate and suture anchor group.The basic exposure procedures were the same as above. It was recommended to select the Langer's line as the incision. After exposing the fracture ends, the coracoid base was revealed by blunt dissection from the gap of anterior bundle of deltoid muscle. The 2.5 mm Kirschner wire was placed along the direction of coracoid process located under fluoroscopy. After accurate positioning, a 5 mm suture anchor was screwed along the direction of Kirschner wire. Two holes were drilled on the clavicle proximal to the fracture ends with 0.5 to 1.0 cm apart from each other. The anchor threads were inserted into the bone holes respectively and tightened to maintain the reduction. With satisfactory radiographic examination, the anatomical clavicular locking plate was fixed, and the sutures from suture anchor should avoid the screw cut. The incision was sutured layer by layer after hemostasis and irrigation.Postoperative management:In the distal clavicular anatomical locking plate group, the affected extremity was hang in the forearm sling for 4 weeks, and the pendulum exercises in the suspension were allowed 3 weeks after operation. Muscle strength exercises started as the radiographic examinations revealed signs of bone callus formation or union. In the joint application of suture anchor group, the shoulder joint exercises in the suspension were initiated immediately as the pain was tolerable, and the muscle strength exercises started 3 weeks later. Both groups of patients were encouraged to perform early wrist and elbow non-gravity activities.4.Follow-up methods:The general data of patients were collected and organized. Postoperative follow ups were conducted for guidance of functional exercises, and observation of fracture healing and internal fixator situations. X-ray films were taken preoperatively, postoperatively and at the end of follow ups, on which the coracoclavicular gap was measured. In the last follow up, the shoulder joint function was assessed, and the pain was evaluated by visual analogue scale (VAS) .5.Statistical analysis:.The SPSS 19.0 software was used for statistical analysis. The enumeration data were analyzed using the χ² test and the measurement data were expressed as mean ± division (±s) . Independent sample t test was used for data analysis. P value <0.05 were regarded as statistically significant.

The 41 patients were followed up for 8 to 26 months with an average of 16 months. All the fractures obtained complete healing without delay union, nonunion or malunion. No complications occurred, such as internal fixator loosening, peripheral fractures, et al. There was no statistical difference in preoperative data between the two groups in terms of gender, age, side, time from admission to operation, distance of coracoclavicular gap. The postoperative radiographs were taken to measure the distance of coracoclavicular gap, and the VAS scores and shoulder joint functional scores were collected for comparison. There was no statistical difference between the two groups in postoperative VAS scores and shoulder functional scores, but there was a statistically significant difference in postoperative and terminal distances of coracoclavicular gap (P<0.05) .

The treatment of Neer type II distal clavicle fractures with distal clavicular anatomical locking plate as substitute for the currently popularized clavicular hook plate can significantly reduce the occurrence of complications such as shoulder joint pain, dysfunction, osteolysis, hook migration, etc. However, it is difficult to achieve firm fixation by using locking screws alone, and there are different degrees of acromioclavicular joint instability after operation. The joint application of suture anchor for functional reconstruction of the coracoclavicular ligament can significantly improve the fixation effect that is closer to the characteristics of the original biomechanics. It allows the patient to perform earlier functional exercises and restore the stability of acromioclavicular joint in the vertical direction, which is a more reliable technique and suitable for young adults, especially those who need early activities.