Revision Total Hip Arthroplasty with Primary Stem or Full-Porous-Coated Long Stem for Aseptic Femoral Component Loosening: A Matched-Pair Study

Figures & data

Table 1 Patient Characteristics

	Primary Stem	Revision Long Stem	P value
Patient number	24	72
Sex			1
Male	16	48
Female	8	24
Age	62.3 ± 18.1	61.2 ± 13.2	0.75
Body mass index	28.0 ± 2.0	28.3 ± 1.7	0.55
Paprosky type			0.67
1	18	57
2	6	15
Preoperative Hip Harris Score	53.8±8.6	55.6 ± 10.3	0.2

Figure 1 Pelvis AP radiograph of 41-year-old patient suffered from stem loosening of primary THA, s/p periprosthetic fracture 2 years after the first RTHA with primary stem and receiving second RTHA. (A) Aseptic loosening of left femoral stem, the arrow shows the subsidence of stem and radiolucency around prosthesis before the first RTHA. (B) Immediate postoperative radiograph of the first RTHA using primary stem, which was ML taper stem from size 12.5mm changed to size 15mm. (C) Periprosthetic fracture (Vancouver type B2) occurred 2 years after the first RTHA surgery. (D) Second RTHA using cementless full-porous-coated long stem and multiple wiring fixation.

Figure 2 Kaplan-Meier survivorship curve compared between primary stem and full-porous-coated long stem groups. (A) Survivorship curve for radiographic change. (B) Survivorship curve for revision.

Table 2 Clinical Outcomes of Primary Stem and Revision Long Stem

	Primary Stem	Revision Long Stem	P-value
Average follow up time (years)	7.6± 3.5	6.8 ± 3.3	0.32
Postoperative Hip Harris Score at latest follow up	86.3±10.7	86.7 ± 9.1	0.72
Cement Condition			<0.001
Cemented→cemented	9	0
Cemented→cementless	0	20
Cementless→cementless	13	52
Cementless→cemented	2	0
Radiographic
Canal fill ratio	84.0 ±5.7	88.9 ±5.9	0.006
Radiographic change			0.69
Stem subsidence	1	2
Periprosthetic fracture	1	1
Stem breakage	0	1
5-year survival rate	91.7%	95.8%
10-year survival rate	91.7%	94.4%
2nd Revision			0.78
Periprosthetic fracture	1	1
Stem breakage	0	1
5-year survival rate	95.8%	98.6%
10-year survival rate	95.8%	97.2%

Figure 3 Pelvis and femoral radiograph of 58-year-old patient suffered from stem loosening after primary THA, intraoperative tip fracture during RTHA, and revision with long stem combined additional ORIF. (A) Aseptic loosening of left femoral stem before RTHA surgery. (B) Intraoperative radiograph revealed periprosthetic femoral shaft split fracture over stem tip (red arrow). (C) Immediate ORIF was performed combined full-porous-coated long stem RTHA. (D) 5 years postoperative radiograph revealed stable prosthesis and fracture union.

Figure 4 Radiograph of 62-year-old patient suffered from long stem breakage 6 years after the first RTHA, which was revised with a new cementless full-porous-coated long stem. (A) Aseptic loosening of right femoral stem, the arrow shows the subsidence of stem and radiolucency around prosthesis with advanced osteolysis. (B) Immediate radiograph of RTHA using full-porous-coated long stem, collar fracture was repaired with cerclage wire. (C) Long stem breakage (red arrow) occurred 6 years after revision surgery. (D) Second RTHA using cementless full-porous-coated long stem with multiple wiring ORIF.