when was the last time patient 4684 received the procedure for a loc exc bone lesion nec in 2102?
select procedures_icd.charttime from procedures_icd where procedures_icd.icd9_code = ( select d_icd_procedures.icd9_code from d_icd_procedures where d_icd_procedures.short_title = 'loc exc bone lesion nec' ) and procedures_icd.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 4684 ) and strftime('%y',procedures_icd.charttime) = '2102' order by procedures_icd.charttime desc limit 1