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

Abstract

Instabilities of the SC joint are a rare injury, accounting for only 3% of all injuries of the shoulder-girdle. While 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 imposes a significant limitation on the lives of affected patients. Currently, there is no established therapeutic algorithm in place. This retrospective case series with prospective collection of data was performed at a level-I trauma centre. 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 of six acute anterior dislocations treated with tape-cerclage in a "figure-of-8" configuration; twelve patients with chronic anterior SC instabilities were treated with autologous tendon grafts. For one 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. Out of 24, 19 patients (79%) with an average age of 32 years ± 15 were available for follow-up. 63% of the patients were male. After a mean follow-up of 57 months, the mean age- and sex-adapted Constant-Murley Shoulder Score (CS) of acute anterior luxations amounted to 90 points ± 20, Nottingham Clavicle Score (NCS) to 81 points ± 22 and DASH Score to 11 points ± 18. Chronic anterior instabilities had a mean CS of 90 points ± 12, NCS of 83 points ± 17 and DASH Score of 4 points ± 5. The study shows a complication rate of 10%. Two patients underwent revision surgery. To conlude, monocortical SCJ fixation in a "figure-of-8" fashion presents a low risk for complication and a low revision rate and can achieve equally good functional outcome after the treatment of highly unstable acute and chronic anterior SCJ instabilities than 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.