Easy and safe: a new surgical fixation technique for acute and chronic anterior instabilities of the sternoclavicular joint: technique and results

Background: Instabilities of the sternoclavicular (SC) joint are a rare injury, accounting for only 3% of all injuries of the shoulder girdle. Although acute posterior dislocations are an emergency and require immediate surgical intervention, anterior instabilities (first and second degree according to Allman) can mostly be treated conservatively. Chronic and highly instable acute anterior instabilities often impose a significant limitation on the lives of affected patients. Currently, there is no established therapeutic algorithm in place.

Methods: This retrospective case series with prospective collection of data was performed at a level I trauma center. Patients treated surgically for anterior SC joint instabilities between January 2013 and December 2019 and with a minimum follow-up of 24 months were included. The injuries comprised 6 acute anterior dislocations treated with tape cerclage in a "figure-of-8" configuration; 12 patients with chronic anterior SC instabilities were treated with autologous tendon grafts. For 1 highly unstable chronic anterior instability, in addition to the tendon graft, synthetic suture material was applied. The clinical evaluation consisted of a physical examination and a standardized questionnaire, which included subjective and objective shoulder scores.

Results: Of 24 patients, 19 (79%) with an average age of 32 ± 15 years were available for follow-up. A total of 63% of the patients were male. After a mean follow-up of 57 months, the mean age- and sex-adapted Constant-Murley Shoulder Score of acute anterior luxations amounted to 90 ± 20 points, the Nottingham Clavicle Score to 81 ± 22 points, and the Disability of the Arm, Shoulder and Hand Score to 11 ± 18 points. Chronic anterior instabilities had a mean Constant-Murley Shoulder Score of 90 ± 12 points, Nottingham Clavicle Score of 83 ± 17 points, and Disability of the Arm, Shoulder and Hand Score of 4 ± 5 points. The study shows a complication rate of 10%. Two patients underwent revision surgery.

Conclusions: To conclude, monocortical SC joint fixation in a "figure-of-8" fashion presents a low risk for complication and a low revision rate and can achieve an equally good functional outcome after the treatment of highly unstable acute and chronic anterior SC joint instabilities as other published techniques. Our approach presents less risk to the neurovascular structures of the mediastinum than other published techniques requiring bicortical drilling, therefore making the technique more accessible to hospitals without a cardiothoracic surgical background.