The parties' stipulation to the fair and reasonable value of past medical expenses in the amount of $166,371.63 should be enforced ( see Sanfilippo v City of New York, 272 AD2d 201, lv dismissed 95 NY2d 887).
Despite being allowed to conduct additional discovery following the first trial of this action ( see 9 AD3d 279), defendants failed to conduct discovery on collateral source issues at any time before the jury returned its verdict after the second trial, and they should not have been allowed to conduct posttrial collateral source discovery ( see Firmes v Chase Manhattan Auto. Fin. Corp., 50 AD3d 18, 37-38, lv denied 11 NY3d 705). In any event, despite plaintiff's compliance with their discovery demands, defendants failed to carry their burden of demonstrating "with reasonable certainty" that plaintiff's past medical expenses and past and future lost earnings were or would be replaced from collateral sources (CPLR 4545 [c]; see generally Oden v Chemung County Indus. Dev. Agency, 87 NY2d 81).
We have not considered plaintiff's remaining argument, which is not properly before us.