He has had a degenerative condition in his knee since high school. Had surgery. Potential that this is career-ending. Family is exhausting all options before making that determination.
Williams missed his entire junior season of high school after having knee surgery to correct a congenital knee condition called osteochondritis dissecans, in which bone underneath the cartilage of a joint dies due to lack of blood flow.
Got that from a UA site. FIrst I've seen it spelled out exactly what was up with the knee, I guess they found it after the ACL tear. Edit apparently it's not actually official he did have an ACL tear they never really confirmed what injury he had in HS people just assumed ACL because he missed a full season. So that may have been the problem in HS too.
Really bad break and now the potential retirement rumors make sense. Hope the kid is able to play again