Total hip arthroplasty using porous-coated femoral
components in patients with rheumatoid arthritis
Jana, A. K., C.A. Jr. Engh, P.J. Lewandowski, R.H. Hopper, C.A.
Engh. 2001. Total hip arthroplasty using porous-coated femoral
components in patients with rheumatoid arthritis. Journal of Bone &
Joint Surgery. July: 83-B (5):686-690.
Presented by Wislaine Coby
Total Hip Anthroplasty (THA)
A surgery to relieve pain and restore
range of motion by realigning or
reconstructing a joint.
Used an Anatomic Medullary Locking
(AML) porous-coated femoral
component, in combination with
different acetabular design
From 1977-1986, performed 82 total hip
arthroplasties (THAS) using the anatomic
medullary locking (AML) femoral
Total of 64 patients: 7 men (8 hips), 57
women (74 hips).
To obtain bony ingrowth
The extent of the porous coating: 65 extensive
and 17 proximal porous coating.
Extensively: 50% of the stem were coated for
diaphyseal bony ingrowth
Proximally: 1/3 of the proximal end was coated
for metaphyseal bony ingrowth
Cup-shaped socket of the hipbone
3 particular types were used
1977-1983: implanted 23 cemented
1983-1985: implanted 20 threaded cups without
1982-1986: implanted 39 porous coated cups
Test the stability of the implant before
operation and during each follow-up using
the Merle D’Aubigne and Postel
Other signs of instability include:
Tilting greater than 5*
Migration more than 2mm
Circumferential radiolucent line
Re-operation among patients
With a minimum follow-up of 2 years, 14
patients had 15 re-operations
One complete revision
14 acetabular revisions
Re-operation in hips
Life Table Of AML Revision
Survivorship of the acetabular
Survivorship for revision due to aseptic
loosening at ten years
Porous coated- 93.8% survivorship, CI= 85.5-
Cemented- 84.3% survivorship, CI=68.0-100.0
Threaded- 54.1% survivorship, CI=27.9-100.0
Results of revision
Majority of the patients with loose or
dislocated cemented or polyethylene
acetabular components were replaced with
the porous coated.
Unrevised cases (56 hips)
This is based on pain and walking ability.
Pain component improved from a mean of 2.6
(preoperatively) to 5.3 (at follow-up).
51 hips had less pain, 2 hips moderate pain, and 3 hips
had more pain.
Walking component: improved from a mean of
2.8 (preoperatively) to 4.3 (at follow-up).
34 hips had great improvement, 11 hips were
moderate, and 11 hips were poor.
Unrevised Cases Cond’t
Radiological follow-up (stability of the
femoral stems and acetabular components)
4 femoral stems were loose and 52 had
49 acetabular components were stable and 7
•THA did provide relief from pain.
•The use of the porous coated stem had good
long term results and was more reliable and