The player is likely to need surgery and looks certain to miss out on the
Olympics as well as the start of next season.
Spector has flown to California for treatment and further advice from national
team director Michael Gerhardt.
The 22-year-old played 28 matches for the Hammers last season, scoring
his first goal for the club in the 5-0 win over Derby County in November.
Spector has previously played for Manchester United and Charlton Athletic.