A total of 170,433 cases of TKA, 13,209 cases of UKA and 8760 cases of tibial osteotomy were identified. The proportion of patients undergoing UKA rose from 4.0% in 2007 to 8.1% in 2014 (P < 0.001), and that of tibial osteotomy from 2.6% in 2007 to 5.5% in 2014 (P < 0.001); the proportion undergoing TKA fell from 93.4% in 2007 to 86.3% in 2014 (P < 0.001). Between 2007 and 2014 the proportions of patients with osteonecrosis who underwent UKA and tibial osteotomy increased from 34.7% and 11.6% to 38.6% and 16.2%, respectively (P = 0.001 for UKA and P = 0.004 for tibial osteotomy). The proportions of patients with osteonecrosis undergoing UKA or tibial osteotomy were significantly greater than those with other diagnoses (P < 0.001 for both).