A biomechanical comparison of new techniques for distal clavicular fracture repair versus locked plating

• Published in: Journal of shoulder and elbow surgery 2019-05, Vol.28 (5), p.982-988
• Main Authors: Yagnik, Gautam P., Brady, Paul C., Zimmerman, Joseph P., Jordan, Charles J., Porter, David A.
• Format: Article
• Language: English
• Subjects: Acromioclavicular Joint - physiopathology; Adult; Aged; Aged, 80 and over; Biomechanical Phenomena; biomechanical study; Bone Plates; Cadaver; Clavicle - injuries; Clavicle - surgery; coracoclavicular button; cortical button; Distal clavicular fracture; distal-third locking plate; Female; Fracture Fixation, Internal - instrumentation; Fracture Fixation, Internal - methods; Fractures, Bone - physiopathology; Fractures, Bone - surgery; Humans; lateral clavicle; Ligaments, Articular - surgery; Male; Middle Aged
• ISSN: 1058-2746; 1532-6500
• DOI: 10.1016/j.jse.2018.11.041

Unstable distal clavicular fractures treated surgically are associated with high failure rates and hardware-related complications. Newer techniques have shown promising early clinical results with fewer hardware complications; however, their biomechanical performance has not been assessed. This study biomechanically compared a distal-third locking plate with 3 newer techniques that incorporate coracoid fixation into the construct. The study randomized 36 adult fresh frozen cadaveric shoulders to 4 groups: (1) distal-third locking plate (P); (2) distal-third locking plate with a coracoid button augmentation (P + CB); (3) coracoclavicular button (CB); and (4) coracoclavicular button with coracoclavicular ligament reconstruction using semitendinosus allograft (CB + CC). After fixation, each specimen was stressed in the coronal plane. Cyclic displacement, load at 10-mm displacement, and ultimate load to failure were measured. All 3 experimental groups biomechanically outperformed the locking plate. Mean load to failure was significantly higher in the CB (343 ± 76 N) and CB + CC (349 ± 94 N) groups compared with the P group (193 ± 52 N). There was also significantly less cyclic displacement in the CB (4.3 ± 1.9 mm) and CB + CC (4.4 ± 1.9 mm) groups compared with the P group (8.2 ± 2.9 mm). With respect to load at 10 mm of displacement, which essentially measures a clinical failure, the P + CB (235 ± 112 N), CB (253 ± 111 N), and CB+CC (238 ± 76 N) experimental groups significantly outperformed the P group (96 ± 29 N). CB and CB + CC techniques demonstrated more than 75% greater strength than the traditional locking plate alone. Coupled with greater overall construct strength and lower-profile hardware, these newer techniques may result in improved clinical outcome and fewer hardware-related complications.