Summary

Arthroscopic ACJ stabilization, tightrope versus CC sling technique

Abstract

Background

Acromioclavicular joint (ACJ) injuries are common shoulder injuries amounting to around 1.8 per 1000 per year. According to the Rockwood classification; grade 1 and 2 are managed non-operatively, grade 4, 5 & 6 require ACJ stabilization while grade 3 injuries are controversial. There is no gold standard technique or fixation device, but fixation should provide a stable ACJ and good functional results. Arthroscopic techniques are gaining popularity, however despite of good functional results, radiological loss of reduction is an issue.

Aim

to compare radiological and clinical outcomes after two different arthroscopic techniques for ACJ stabilization in acute cases.
Patients and Methods: From July 2016, through Dec 2020, a randomized trial was performed at our hospital. Fifty patients with acute (≤ 3 weeks) Rockwood grade III-VI ACJ dislocation were included in the study. Patients with associated coracoid fracture, associated rotator cuff tears or gleno-humeral arthritis were excluded. Patients were randomized into 2 groups; group A (25 patients) were managed using arthroscopic double tight rope technique. While the remaining 25 patients (group B) were treated using arthroscopic coraco-clavicular sling technique. Constant and Oxford shoulder scores along with pain visual analogue score are used to assess functional outcomes. Radiological loss of reduction was assessed by measuring coraco-clavicular distance immediately post-operative and at final follow-up at 1 year. In group A, coracoid tunnel diameter is measured from the widest coracoid diameter in the axial cut of a multi-slice CT scan immediately post-operative and at 1 year using a computer software RadiAnt viewer

Results

there was a statistically significant difference between both groups regarding loss of reduction. Although all cases experienced radiological loss of reduction, it was significantly higher in group A. The operative time in group B was significantly shorter than group A. there was however, no statistically significant difference between both groups regarding clinical outcomes and functional scores. In group A, the coracoid tunnel diameter to horizontal coracoid diameter ratio increased from 22.8 ± 3.66 % immediately postoperative to 38.52 ± 5.46 % after 12 months (p<0.001)

Conclusion

Arthroscopic techniques are gaining popularity and in the hands of experts; the technically demanding procedure can be performed in a shorter period of time. Double tight rope technique carries the risk of coracoid fracture or tunnel widening with subsequent possible loss of reduction. Arthroscopic CC sling is a quicker, less demanding, more economic procedure and yields equivalent functional outcomes