Recent data has challenged the historical precedent of nonoperative care for many clavicle fractures; clinical and biomechanical studies have shown altered joint-contact forces occur in the glenohumeral joint (GHJ) after fracture and shortening of the clavicle. However, to date, there have been no analyses documenting the long-term effects of these altered shoulder girdle mechanics on the GHJ.
The clavicles of 2899 cadaveric skeletons were manually inspected for evidence of fracture. Shortening, fracture location, and laterality were recorded along with demographic information. Degenerative joint disease of the GHJ was graded. Correlations between the presence of a clavicle fracture and ipsilateral GHJ osteoarthritis were evaluated with multiple regression analysis using an age-, gender-, race-, and laterality-matched control group of 1154 GHJs.
One hundred three specimens had 104 clavicle fractures, a prevalence of 3.6% (103/2899) in this collection. There was a strong correlation between the presence of an ipsilateral clavicle fracture (standardized beta 0.108, P < 0.001), age (standardized beta 0.332, P < 0.001), male gender (standardized beta -0.069, P = 0.009), and laterality (right sided, standardized beta 0.056, P = 0.032) on the development of GHJ arthritis. There was a trend toward increased GHJ arthritis in specimens with shortening >20 mm (standardized beta 0.156, P = 0.109), although this subanalysis may have been underpowered.
This is the first study to report long-term consequences of clavicle fracture on the development of ipsilateral GHJ osteoarthritis; clavicle fractures were shown to have a higher degree of GHJ osteoarthritis. Future clinical studies are needed to confirm these relationships.