Description
Objectives: To find out if there is a difference in clinical and radiological outcomes between the two commonly used endobutton systems for acromioclavicular joint (ACJ) reconstruction
Methods: A retrospective study was conducted in a tertiary hospital in Singapore. A total of 22 patients (12 TightRope and 10 Dog Bone) were included in the study. Patient demographics were collected from the institution’s online medical records. The University of California Los Angeles Shoulder Score (UCLA) and Oxford shoulder score (OSS) were assessed at 1 year post-operation. Measurement of the coracoclavicular distance was done using plain radiographs obtained on post-operative day one (POD 1) and at 6-months postoperatively (POD 6m). A displacement of ≥5mm on plain radiographs compared to the contralateral side on POD 1 is considered a lack of reduction while the same degree of displacement at 6-months is considered a loss of reduction. A statistical significance is taken as p<0.05.
Results: Three patients had early operative failure, where there was complete recurrence of the ACJ dislocation on POD 1 radiographs. Two were in the TightRope group (Figure 1), while one was in the Dog Bone group. One patient each in the TightRope and Dog Bone groups had lack of reduction with >5mm displacement compared to the contralateral (normal) side on POD 1 radiographs. Plain radiographs at POD 6m show a loss of reduction in four of eight remaining patients (50%) from the Dog Bone group (Figure 3), compared to two of nine remaining patients (22.2%) from the TightRope group, but this was not statistically significant (p=0.232). The UCLA shoulder score and Oxford shoulder score at 1-year post-operation were good without significant difference between the two groups.
Conclusion: ACJ reconstruction with the endobutton systems have good clinical outcomes, and are similar between the Dog Bone and TightRope implants.