Cotyloplasty in cementless total hip arthroplasty for an insufficient acetabulum.
BACKGROUND
Cotyloplasty is a technique that involves making a perforation of the medial wall of a shallow acetabulum and then inserting an acetabular cup with the medial aspect of its dome beyond the Kohler line. The purpose of this study was to evaluate the results of cementless total hip arthroplasty (THA) using cotyloplasty with focusing on the amount of medial cup protrusion.


METHODS
Sixteen hips with insufficient acetabulum in sixteen patients were treated by cementless THA using cotyloplasty. The average patient age was 47 years. The diagnoses included dysplastic hip (12) and infection sequelae (4). All the patients were followed up for at least 2 years. Clinically, the Harris hip scores were assessed and radiologically, the amount of cup protrusion, the hip center movement and cup fixation were evaluated.


RESULTS
The average Harris hip score improved from 57 to 94 postoperatively. The average proportion of cup surface beyond the Kohler line was 44.1% and the hip centers were medialized by an average of 23 mm. Stable fixation of the acetabular cup was achieved in all the cases except one. In this one case, migration of the cup was detected 2 weeks postoperatively and a reoperation was performed.


CONCLUSIONS
Using cotyloplasty, good coverage of the acetabular cup was obtained without a block bone graft, and the hip joint centers were medialized. However, the safety margin for the amount of protrusion should be established.
Kim
Yong Lae
YL
Department of Orthopaedic Surgery, Inchon Medical Center, Inchon, Korea.
Nam
Kwang Woo
KW
Yoo
Jeong Joon
JJ
Kim
Young-Min
YM
Kim
Hee Joong
HJ
D000077:Acetabulum / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D000328:Adult; D001170:Arthritis, Infectious / Q000150:complications / Q000473:pathology; D019644:Arthroplasty, Replacement, Hip; D005260:Female; D006618:Hip Dislocation, Congenital / Q000473:pathology / Q000601:surgery; D006621:Hip Joint / Q000000981:diagnostic imaging; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography
J Bone Joint Surg Am. 1976 Sep;58(6):838-45
956229
J Bone Joint Surg Br. 1990 Jan;72(1):53-9
2298795
J Bone Joint Surg Br. 1988 Mar;70(2):182-6
3346284
J Arthroplasty. 1990 Sep;5(3):231-40
2230819
J Arthroplasty. 2005 Aug;20(5):562-7
16309989
J Arthroplasty. 1996 Jan;11(1):81-5
8676123
Clin Orthop Relat Res. 1973 Mar-Apr;(91):98-113
4574070
Clin Orthop Relat Res. 1992 Sep;(282):132-44
1516304
J Bone Joint Surg Am. 1979 Jan;61(1):15-23
365863
J Bone Joint Surg Am. 1978 Mar;60(2):217-20
641088
Clin Orthop Relat Res. 1988 Feb;227:164-71
3338205
J Bone Joint Surg Am. 1999 Jan;81(1):83-92
9973058
J Arthroplasty. 1999 Feb;14(2):131-7
10065716
J Bone Joint Surg Br. 1998 Jul;80(4):585-90
9699816
J Bone Joint Surg Am. 1969 Jun;51(4):737-55
5783851
J Bone Joint Surg Am. 1996 May;78(5):683-92
8642024
J Bone Joint Surg Am. 2001 Oct;83(10):1484-9
11679597
Clin Orthop Relat Res. 1990 Jun;(255):173-85
2347151
J Bone Joint Surg Am. 1990 Aug;72(7):1025-34
2384501