How to convert December-2017 to 201712

DECLARE @InputDate NVARCHAR(50) = 'December-2017'
DECLARE @Index INT = CHARINDEX('-',@InputDate)
DECLARE @MonthName NVARCHAR(20)= UPPER(SUBSTRING(@InputDate,0,@Index))
DECLARE @YearDate NVARCHAR(20) = SUBSTRING(@InputDate,@Index + 1,(LEN(@InputDate) - @Index) + 1)

SELECT @YearDate+(CASE WHEN @MonthName = 'JANUARY' THEN '01'
			 WHEN @MonthName = 'FEBRUARY' THEN '02'
			 WHEN @MonthName = 'MARCH' THEN '03'
			 WHEN @MonthName = 'APRIL' THEN '04'
			 WHEN @MonthName = 'MAY' THEN '05'
			 WHEN @MonthName = 'JUNE' THEN '06'
			 WHEN @MonthName = 'JULY' THEN '07'
			 WHEN @MonthName = 'AUGUST' THEN '08'
			 WHEN @MonthName = 'SEPTEMBER' THEN '09'
			 WHEN @MonthName = 'OCTOBER' THEN '10'
			 WHEN @MonthName = 'NOVEMBER' THEN '11'
			 WHEN @MonthName = 'DECEMBER' THEN '12'
			ELSE '' END)