Deficits of handgrip strength (n = 50) 13 Time of exam Grade After 6 months After 12 months No deficit (< 5%) 36 42 Mild (5% - 30%) 13 8 Moderate (30% - 50%) 1 0 Total 50 50 6 months post-operatively, 13 (26%) patients had mild deficits.