This is a different option using Pattern Splitting (using Lynn's sample data).
select
*
from dbo.TestData td
cross apply (select stuff((select ',' + ca.Item
from dbo.PatternSplitCM(td.TestValue,'%[0-9]%') ca
where ca.Matched = 1
for xml path(''),TYPE).value('.','nvarchar(max)'),1,1,'')) ca3(IDs)
The function and explanation can be found in here:
http://www.sqlservercentral.com/articles/String+Manipulation/94365/