Treatment of stress-controlled clavicle hook plate internal fixation for acromioclavicular joint dislocation

YU Xinjian; SI Huifeng; YANG Yu; WANG Jing; XU Ruisheng

doi:10.3969/j.issn.1674-666X.2025.02.002

Abstract：Objective To explore the clinical effect of internal fixation with clavicular hook plate under stress control in the treatment of acromioclavicular joint dislocation.Methods A retrospective analysis was conducted on the clinical data of 45 patients with acromioclavicular joint dislocation who underwent internal fixation with clavicular hook plates from February 2020 to April 2024.Among them,24 patients fixed with clavicle hook plate were included into the control group,21 patients treated with stress-controlled clavicle hook plate internal fixation were included into the observation group.The stress control method included 3 steps,increasing the hook angle at the distal end of the clavicle hook plate,removing the bony tissue 2-5 mm above the posterior acromion end of the clavicle,and bending the hook plate,so as to control the stress of the clavicle hook plate between the clavicle and the acromion.Vertical distance between clavicle and the inner side of hook plate in the stress-free state after implantation was measured,and after pressing the plate attached to the clavicle,the stress when the inner side of the plate close to the clavicle was also measured.Visual analogue scale(VAS)scores at 12 d after the operation,the Karlsson standard assessment results of the shoulder joint at 1 and 3 months postoperatviely,and the Constant-Murley score at the last follow-up of patients in the two groups were observed,and the occurrence of postoperative complications was recorded.Correlations between the stress and the plate-clavicle vertical distance was analyzed,and the reasonable range of stress control during the internal fixation by clavicle hook plate was determined.Results All patients were followed up with an average follow-up time of 11 months(ranging from 7 to 19 months).VAS score at 12 d after the operation,the assessment results of the Karlsson standard of the shoulder joint at 1 and 3 months after the operation,and the Constant-Murley score at the last follow-up in the observation group were all better than those in the control group,the difference between the two groups was statistically significant(P<0.05).At the last follow-up,there were 2,6 cases of shoulder pain,1,4 cases of significant shoulder joint movement limitation,and 4,6 cases of subacromial bone resorption in the observation group and the control group respectively.The incidence of complications in the control group was significantly higher than that in the observation group(66.7%vs 33.3%,P<0.05).The linear regression analysis indicated that the vertical distance between the inner side of the clavicle hook plate and the clavicle had a significant effect on the stress;Compared with that of the control group,the vertical distance between the inner side of the plate and the clavicle in the observation group had a more significant effect on the stress when pressing the plate attached the clavicle(P<0.05).The regression analysis of relations between stress and Constant-Murley score at the last follow-up indicated that the reasonable range of stress control for internal fixation of acromioclavicular hook plate in the treatment of acromioclavicular joint dislocation was 17-25 N,and the vertical distance was 8-13 mm.Conclusion The internal fixation of the clavicular hook plate under stress control for the treatment of acromioclavicular joint dislocation could better improve the postoperative shoulder joint function,relieve pain symptom and reduce the risk of postoperative complications by regulating the stress of the hook plate between the clavicle and the acromion.