Does surgeon handedness affect the outcomes after primary total knee arthroplasty? A retrospective cohort study

Table 4 Summary of the results reported in the previous studies

Ref.	Number of patients (knees)	Dominant side	Non-dominant side	Number of surgeons	Surgeons’ handedness	Radiological (dominant vs non-dominant)			Functional (dominant vs non-dominant)
						HKA	MPTA	LDFA
Mehta and Lotke[27]	688 (728)	377	351	One	Right-handed	NR	NR	NR	Knee extension 1.25 vs 1.75 (P = 0.19), KS function 73.5 vs 70.5 (P = 0.03), KS pain 95 vs 87 (P = 0.029)
Liu et al[28]	86 (100)	50	50	One	Right-handed	1.9 ± 4.4 vs 2.3 ± 3.8 (P = 0.634)	90.0 ± 2.5 vs 90.1 ± 2.6 (P = 0.855)	88.6 ± 2.8 vs 88.4 ± 2.5 (P = 0.616)	HSS score was 87.2 ± 4.3 vs 86.8 ± 5.0 (P = 0.639).
Jaglarz et al[30]	200 (200)	102	98	Four	2 right-handed, and 2 left-handed1	For the right-handed surgeons: No difference in the radiological outcomes regardless of the side of surgery and regardless of their standing position during surgery. For the left-handed surgeons: A significant difference in the HKA [-1.5 (-2.6 to -1) vs -3 (-4.5 to -2), P = 0.01] for surgeon B. A significant difference in the MPTA [0 (-1 to 0.5) vs 1 (0-2), P < 0.01] for surgeon D			NR
Current study, (2025)	370 (370)	177	193	Five	Right-handed	177.96 ± 3.13 vs 178.55 ± 3.38, (P = 0.082)	88.90 ± 2.61 vs 89.43 ± 2.71, (P = 0.056)	90.16 ± 2.54 vs 89.76 ± 2.53, (P = 0.140)	KSS: 80.59 ± 14.73 vs 79.56 ± 15.64 (P = 0.628)

¹Details of involved surgeons: Surgeon A: Right-handed, stands always on the right side (left/right: 23/27), Surgeon B: Left-handed, stands always on the left side (left/right: 28/22), Surgeon C: Right-handed, stands at the side of the operated knee (left/right: 26/24), and Surgeon D: Left-handed, stands at the side of the operated knee (left/right: 23/27).

NR: Not reported; HKA: Hip to knee to ankle; MPTA: Medial proximal tibial angle; LDFA: Lateral distal femoral angle; HSS: Hospital of special surgery; KS: Knee society; KSS: Knee society score.