Are apartment complexes liable for injuries from falls for snowy/icy sidewalks?

Since it was actively snowing on Christmas night, it will be difficult to pursue a claim.  In Colorado, the common area of an apartment complex should be maintained in a safe condition for both the residents and visiting guests, but the apartment owner, or maintenance company, only has an obligation to exercise reasonable care.  If the snow and ice had accumulated over several days without attention by a crew, then perhaps you would have a claim.  But since it was snowing that evening, and it was a national holiday, I don't think a jury would find the apartment manager unreasonable in not having a crew out until the next day.  I am sorry for your injury and hope you enjoy a full and speedy recovery.