2015 ISAKOS Biennial Congress Paper #0

Does Clavicular Inter-Tunnel Distance Ratio Affect Radiographic Failure After CC-Stabilization Of Acute Acromioclavicular Joint Dislocation?

Chavithorn Ongkanchana, MD, Bangkok THAILAND
Thun Itthipanichpong, MD, Bangkok THAILAND
Thanathep Tanpowpong, MD, Bangkok THAILAND
Somsak Kuptniratsaikul, MD, Pathumwan, Bangkok THAILAND
Surasak Srimongkolpitak, MD, Bangkok THAILAND
Thongchai Laohathaimongkol THAILAND
King Chulalongkorn Memorial Hospital and Queen Savang Vhadana Memorial Hospital, Pathumwan and Sriracha, Bangkok and Cholburi, THAILAND

FDA Status Cleared

Summary: Can clavicular inter-tunnel distance ratio help predicting radiographic outcome after CC-stabilization in patients with acute acromioclavicular joint dislocation?

Abstract:

Background

Acute acromioclavicular joint dislocation was one of the most common injuries of the shoulder. CC-stabilization has been popularized as one of the mainstay treatments for this injury. However, re-dislocation after this procedure is still one of the crucial problems that we face today. This study's main objective was to evaluate the clavicular inter-tunnel ratio as a new potential predictor of postoperative radiographic failure.

Methods

This multicenter retrospective cohort study included patients aged 18 – 60 years old who underwent cc-stabilization after acute acromioclavicular joint dislocation and had follow-up data for at least 6 months postoperative. Patient’s demographic data, operative details and radiographic parameters (conoid & trapezoid ratio / clavicular inter-tunnel ratio / inter-tunnel angle / reduction degree) were collected. Radiographic failure was determined at 6 months after surgery.

Results

A total of 86 subjects were included in this study. The radiographic failure rate in this study was 48.84% (42/86). The clavicular inter-tunnel ratio showed no statistically significant difference between both groups (8.76 ± 0.43% VS 8.3 ± 0.35%, p=0.32). Neither conoid nor trapezoid ratio was different between both groups. However, the initial reduction degree was statistically significantly different between both groups (p=<0.001). Over-reduction of clavicle could reduce the risk of radiographic failure (15.38% VS 34.29%). On the other hand, under-reduction could increase the risk (73.68% VS 34.29%).

Conclusion

Clavicular inter-tunnel ratio failed to show any association with radiographic failure at 6 months. However, the initial reduction degree greatly affected the radiographic outcome. Further work with more advanced imaging that could cover all of the potential factors is needed to specify the causes of radiographic failure after this operation.