Female-specific vs conventional knee prostheses after total knee arthroplasty: A meta-analysis

Table 1 Baseline characteristics of included trials

Study ID	Implant used		Sample size (knees)		Study design	Mean age (yr)		Follow-up (mo)	BMI (kg/m2)
	GSP	CP	GSP	CP		GSP	CP		GSP	CP
Kim et al[14]	Gender-specific CR- Flex	Standard CR- Flex	138	138	RCT	71.2	71.2	39	27.3	27.3
Kim et al[15]	Gender-specific LPS-Flex	Standard LPS-Flex	85	85	RCT	69.7	69.7	25.6	27.1	27.1
Tanavalee et al[16]	Gender-specific LPS-Flex	Standard LPS-Flex	165	149	CCT	70	70.5	24	23.4	23.5
Singh et al[17]	Gender-specific LPS High-Flex	Standard LPS-Flex	100	100	RCT	64	68	24	30.7	31.1
Song et al[18]	Gender Solutions	Standard CR- Flex	46	46	RCT	68.8	68.8	31.5	26.8	26.8
Lionberger et al[19]	Gender-specific CR or LPS-Flex	Standard CR- Flex	39	39	CCT	67.9	68.3	12	29.9	30
Thomsen et al[20]	Gender Solutions high-Flex	Standard LPS-Flex	22	22	RCT	66	66	13	29.3	29.3

GSP: Gender-specific prostheses; CP: Conventional prostheses; BMI: Body mass index; CR: Posterior cruciate retaining; LPS: Legacy posterior stabilized; RCT: Randomized controlled trial; CCT: Case control trial.

Table 2 Designs and methodological quality summary

Study	Sequence generation	Allocation concealment	Assessor blinding	Incomplete outcome	Selective reporting
Kim et al[14]	Yes	Yes	Unclear	Yes	Yes
Kim et al[15]	Yes	Yes	Yes	Yes	Yes
Tanavalee et al[16]	No	No	No	Yes	Yes
Singh et al[17]	Yes	Unclear	Unclear	Yes	Yes
Song et al[18]	Yes	Unclear	Yes	Yes	Yes
Lionberger et al[19]	No	No	No	Yes	Yes
Thomsen et al[20]	Yes	Unclear	Yes	Yes	Yes

Yes: Low risk of bias; Unclear: Moderate risk of bias; No: High risk of bias.

Table 3 Clinical results: preoperative and postoperative range of motion, Hospital for Special Surgery scores

Study	Preoperative ROM		P	Postoperative ROM		P	Preoperative HSS		P	Postoperative HSS		P
	GSP	CP		GSP	CP		GSP	CP		GSP	CP
Kim et al[14]	127 (100-150)	123 (80-150)	NR	124 (85-140)	126 (85-140)	NR	NR	NR	NR	NR	NR	NR
Kim et al[15]	123 (85-150)	120 (58-150)	0.139	126 (85-140)	125 (80-140)	0.739	59.7 (37-58)	59.1 (37-68)	0.120	91.2 (77-100)	90.7 (84-100)	0.252
Tanavalee et al[16]	126	125.6	> 0.05	134.1	133.5	> 0.05	NR	NR	NR	NR	NR	NR
Singh et al[17]	111.7 ± 13.5	110.5 ± 13.7	0.282	122.8 ± 8.0	119.9 ± 8.7	0.007	55.7 ± 9.1	56.7 ± 9.0	0.212	91.5 ± 4.8	91.9 ± 4.1	0.313
Song et al[18]	120.4 ± 16.6	121.8 ± 13.5	0.64	131.1 ± 9.2	133.7 ± 19.2	0.16	57.5 ± 11.5	57.1 ± 12.1	0.880	92.7 ± 8.0	92.1 ± 8.7	0.75
Lionberger et al[19]	102.7 ± 9.5	107.5 ± 11.5	0.048	123.4 ± 9.8	118.3 ± 9.7	0.023	NR	NR	NR	NR	NR	NR
Thomsen et al[20]	NR	NR	NR	125 (105-142)	125 (105-139)	0.82	NR	NR	NR	NR	NR	NR

ROM: Range of motion; HSS: Hospital for special surgery scores; GSP: Gender-specific prostheses; CP: Conventional prostheses; NR: Not reported.

Table 4 Clinical results: preoperative and postoperative Knee Society score

Study	Preoperative KSS clinical score		P	Postoperative KSS clinical score		P	Preoperative KSS function score		P	Postoperative KSS function score		P
	GSP	CP		GSP	CP		GSP	CP		GSP	CP
Kim et al[14]	39.8 (10-70)	35.3 (0-50)	0.149	93 (70-100)	94 (70-100)	0.69	44.2 (20-70)	44.2 (20-70)	1.000	84 (60-100)	83 (60-100)	0.322
Kim et al[15]	34.4 (7-62)	31.2 (0-55)	0.145	96.5 (83-100)	95.5 (81-100)	0.424	48.3 (20-80)	47.9 (20-80)	0.320	84.8 (60-100)	84.8 (60-100)	NR
Tanavalee et al[16]	34.3	34.7	> 0.05	92.1	92.9	> 0.05	32.2	31.8	> 0.05	89.7	89.5	> 0.05
Singh et al[17]	34.2 ± 11.5	36.3 ± 13.4	0.118	94.9 ± 4.7	95.8 ± 3.6	0.061	37.6 ± 14.0	38.7 ± 10.2	0.254	80.2 ± 10.6	79.9 ± 13.0	0.429

Relevant data were not available for the other 3 studies. KSS: Knee Society score; GSP: Gender-specific prostheses; CP: Conventional prostheses.

Table 5 Outcomes of complications comparing female-specific with conventional prostheses

Complications	Incidence		Odds ratio (95%CI)	Overall effect(P value)	I2(%)	HeterogeneityP
	GSP	CP
Manipulation under anesthesia[16,17]	0/265	4/249	0.19 (0.02-1.61)	0.13	0	0.97
Revisions[14,16]	1/293	2/286	0.57 (0.07-4.34)	0.55	0	0.64
Anterior knee pain[17]	5/50	4/50	1.28 (0.32-5.07)	0.73	NA	NA

GSP: Gender-specific prostheses; CP: Conventional prostheses; CI: Confidence interval; NA: Not applicable.