Reconstruction of Paprosky type IIIB acetabular bone defects using a cup-on-cup technique: A surgical technique and case series

Table 1 Patients’ demographic data

Patient	Age (yr)	Gender	Height (cm)	Weight (kg)	Initial diagnosis	Prior surgeries
1	73	F	157	53	Femoral neck fracture, Lt.	2014 THA
2	57	F	152	73	Osteonecrosis, Lt.	2006 THA
3	29	M	180	98	Posttraumatic acetabular comminuted fracture, Lt.	September 21, 2012 internal fixation, September 29, 2012 debridement × 3 (September 2012; October 2012; September 2014), January 2015 debridement + antibiotic-PMMA beads
4	60	F	160	65	Osteonecrosis, Lt.	2002 THA
5	67	M	178	82	Osteoarthritis, Rt.	2005 THA
6	69	F	157	69	Osteoarthritis, Rt.	2009 THA

F: Female; M: Male; Lt: Left; Rt: Right; THA: Total hip arthroplasty; PMMA: Polymethyl methacrylate.

Table 2 Implants used

Patient	TM-Cup augment diameter (mm)	Acetabular component	Total number of screws	Liner	Femoral head diameter (mm)
1	48	54 mm Pinnacle	3	HXLPE	36
2	52	58 mm Pinnacle	3	Ceramic	36
3	48	58 mm TM revision shell	5	HXLPE	36
4	50	56 mm TM revision shell	4	HXLPE	32
5	52	60 mm Pinnacle	4	HXLPE	36
6	48	58 mm TM revision shell	5	HXLPE	36

TM: Trabecular metal; HXLPE: Highly cross-linked polyethylene.

Table 3 Comparison of studies reporting reconstructions for Paprosky type III acetabulum bone defects with tantalum metal augments

Ref.	Number and Paprosky type	Reconstruction technique for defects	Mean follow-up	Mean postoperative hip score	Failure resulting from aseptic loosening	Other complications requiring reoperation
Lingaraj et al[8]	17 IIIA, 6 IIIB without pelvic discontinuity	21 TM shell-augment; 1 TM shell alone; 1 acetabular component-cage	41 mo (range, 24 to 62)	Harris hip score 75.7 (range, 53 to 100)	0	2 recurrent instability, 1 early infection with irrigation and debridement
Sporer et al[9]	28 IIIA	The TM shell-augment in all cases	3.1 yr (range, 1 to 4 )	The modified Merle d’Aubigne and postel score 10.6	0	1 recurrent instability
Del Gaizo et al[10]	37 IIIA	The TM shell-augment in all cases	60 mo (range, 26 to 106)	Harris hip score 81.5 (range, 27.0 to 99.8)	1 (2.7%)	5 recurrent instability, 4 infection with irrigation and debridement, 2 periprosthetic femoral fracture
Grappiolo et al[11]	42 IIIA, 13 IIIB without pelvic discontinuity	The TM shell-augment in all cases	53.7 mo (range, 36 to 91)	Harris hip score 90.5 (range, 61 to 100)	3 (5.5%)	1 recurrent instability
Current study	6 IIIB without pelvic discontinuity	The cementless acetabulum component and TM-Cup augment in all cases	42 mo (range, 36 to 52)	Harris hip score 80.7 (range, 71.5 to 87.5)	0	1 greater trochanteric migration

TM: Trabecular metal.