Biomechanical Study On Ligament Repair And Treatment Of Rockwood Ⅲ Acromioclavicular Joint Dislocation

With the development of modern transportation industry, the progress of science and technology, the popularity of private cars, traffic accidents have been significantly increased, leading to the increase of patients with acromioclavicular joint dislocation. Biomechanical study of treatment and ligament, this paper mainly introduces the III type acromioclavicular joint dislocation. The clinical manifestations of III type acromioclavicular joint dislocation of acromioclavicular ligament is fracture; dislocation of acromioclavicular joint, shoulder joint down; coracoclavicular ligament rupture; coracoclavicular gap compared with the healthy side increased by 25% ~ 100%; trapezius, deltoid splitting from the supraclavicular. The prevalence rate of great men(male to female ratio 5:1 to 10:1), wherein the subluxation prevalence rate is 2 times the prevalence of complete dislocation. Rowe statistical analysis of 1603 cases of acromioclavicular joint damage in the patients with acromioclavicular joint dislocation in 52 cases, Thorndike in 578 cases of statistical athletes of shoulder joint injury, 223 cases of acromioclavicular joint dislocation, including hockey and rugby player sees more most. Repair in the treatment of III type acromioclavicular joint dislocation is extremely important, current domestic and foreign scholars in the study of treatment, according to the ligament repair is controversial, some scholars believe that the acromioclavicular and coracoclavicular ligament should be repaired at the same time; some scholars think should rebuild acromioclavicular ligament complex, no special repair of coracoclavicular ligament can the satisfactory results. At home and abroad for the III type dislocation of acromioclavicular joint biomechanics research, mainly in the mice body. The results of the existence of differences. So the test to the human body as the experimental body, the results more persuasive and provide effective guidance for clinical treatment.Objective:The purpose of this study is to demonstrate through the clavicular hook plate internal fixation for the treatment of RockwoodIII type shoulder whether clavicular joint dislocation can also repair of acromioclavicular and coracoclavicular ligament. Through the research on the biomechanics, to further understand the problem of ligament repair.Methods:1. To select qualified experimental specimens(16 fresh adult acromioclavicular joint, adult male, no dislocation and deformed). 2. Cryopreservation(specimen closed with plastic bags, outer with several layers of dressing). 3. The room temperature thaw(help thaw in physiological saline). 4. Repair specimens, completely retained the acromioclavicular ligament with beaks lock ligaments. 5. The modification of 16 specimens of bone, ligament, bone structure were randomly divided into A, B two groups, group A; Group B to cut off the rim lock ligament(see figure 6), only keep the acromioclavicular ligament. Adopt LYF a 201 b multi-function machine, the load rate of 100 mm/min under the status of the two groups of ligament stretching mechanics, computer records in connection with the biomechanical testing machine and drawing stress- strain curve and record each ligament rupture strength and fracture deformation.Results:In group A ligament stretch 100 mm/min, the average fracture strength is 645.99 N. Group B in ligament stretch 100 mm/min, the average fracture strength of 551.33 N, the strength of the beak ligament locked far less than the acromioclavicular ligament is strong, but in stability in maintaining clavicle have a little stable stable function. By means of the acromioclavicular ligament and beak lock ligament tension, according to the contrast between the acromioclavicular ligament in maintaining stability play an important role in the process of the acromioclavicular joint. Based on this, we advocate in the surgical treatment of acromioclavicular joint dislocation should focus on repairing the acromioclavicular ligament. To beak lock can be special exposure and ligament repair, such shorter operation time, small trauma, fewer complications, and postoperative effect can also be guaranteed.Conclusion:By comparing the acromioclavicular ligament and beak ligament tension lock, the results showed acromioclavicular ligament can maintain the stability of the acromioclavicular joint significantly. Based on this, we advocate the operation in the treatment of dislocation of acromioclavicular joint should be rebuilt in a complex acromioclavicular ligament, without coracoclavicular ligament special exposure and repair of coracoclavicular ligament. The first patient operation process is relatively simple, shorten the time, small trauma, complications, and postoperative relative reduction effect can also be satisfied.