ICD-10-CM > M00-M99 > M70-M79 > M70 > M70.4 M70.4 Prepatellar bursitis Non-Billable/Non-Specific Codes M70.40Prepatellar bursitis, unspecified kneeM70.41Prepatellar bursitis, right kneeM70.42Prepatellar bursitis, left knee