Objective To investigate technical points,risks and advantages of primary total knee arthroplasty (TKA) through subvastus approach.Methods The study involved 68 patients of similar basic conditions who were treated by TKA between September 2008 and August 2010,including 34 patients treated through subvastus approach (Group A) and 34 patients treated through traditional medial parapatella approach (Group B).Clinical parameters between groups were comparatively studied after operation.Results All patients were followed up for 6-25 months (mean 8.7 months).Alignment of lower extremities in both groups was restored.Group A showed significant differences from Group B in aspects of postoperative drainage volume [(124 ± 32.4) ml vs (182 ± 41.3) ml,P < 0.05],requirement of lateral retinacular release (7% vs 23%,P <0.01),time before patients being capable of having active straight-leg-raising movement [(1.3 ± 0.7) d vs (3.2 ± 0.6) d,P < 0.05],and time away from patients being able to bend their leg up to 90° [(3.1 ± 0.6) d vs (5.3 ± 0.5) d,P < 0.05].Conclusion Primary total knee arthroplasty through subvastus approach can hardly intervene in extension knee apparatus and in blood circulation around patellas,promote rapid recovery of knee function and achieve satisfactory early outcomes.