Objective To investigate the effect of two different osteotomy methods on lower limb align⁃ment and cartilage degeneration in patients with total knee arthroplasty（TKA）. Methods From January 2019 toApril 2021，97 patients in our hospital who were scheduled to undergo TKA were selected and randomly dividedinto a gap group（n = 49）and a measurement group（n = 48）by random number table. Bone method. Perioperativeindicators，lower limb alignment indicators，cartilage degeneration indicators，trauma stress indicators，visualanalogue scale（VAS），New York Hospital for Special Surgery（HSS）knee joint score，and complications werecounted between the two groups. Results （1）The amount of distal femoral osteotomy and the thickness of thepolyethylene cushion in the gap group were greater than those in the measurement group（P < 0.05）；（2）SerumCor and NE levels in the two groups were higher than those before surgery on the 3rd day after surgery（P < 0.05）；（3）The OPG and PANKL levels in the 1 month and 3 months interval group were lower than those in the measure⁃ment group（P < 0.05）；（4）MPTA and LDFA in the 1 month and 3 months interval group were lower than thosein the measurement group，and ROM was higher than that in the measurement group（P < 0.05）；（5）VAS scoresin the 1 month and 3 months interval group were lower In the measurement group，the HSS score was higher thanthat in the measurement group（P < 0.05）；（6）There was no statistically significant difference in the total inci⁃dence of complications between the two groups（P > 0.05）. Conclusion The gap balance method is better thanthe measurement osteotomy method in terms of lower limb force line，cartilage degeneration，pain and knee functionrecovery，and it is especially suitable for patients with TKA.