Effects of Fusion Angle on Functional Results Following Non-operative Treatment for Fracture of the Neck of the Fifth Metacarpal

Aim: To investigate in fractures of the fifth metacarpal neck whether there is any difference in functional results of non-operative treatments with dorsal angulation either below or above 30 degrees.

Methods: After closed reduction, fractures were treated with plaster splints for 5 weeks. Cases were divided into two groups, with dorsal angulation either below (group 1) or above (group 2) 30 degrees, according to oblique radiography, and were evaluated at 6 months. Grip strength, range of passive joint movement and distance from fingertip to distal crease were measured and compared. A scoring system assessed function, and occupational adequacy, patient satisfaction and presence of pain were recorded.

Results: Functional outcome was good or very good in both groups and occupational adequacy was not reduced in any case. Full patient satisfaction was achieved except for one person in group 1 and two people in group 2, regarding cosmetic results. There was no statistically significant difference between the two hands in either group except for one man from group 2, who had mild pain during coercive use of the injured hand.

Conclusions: With non-operative treatment of fractures of the neck of the fifth metacarpal, similar results were achieved with dorsal angulation either above or below 30 degrees. A dorsal angulation less than 45 degrees may be treated conservatively.