Tuesday, January 17, 2012

What parts are replaced in a revsion?

I saw a post op report from one of our readers and noticed that just the ball was replaced and not the cup.  I was unfamiliar with this process so I looked it up to see if others in fact have only one part of the hip replaced.  Here is what I found in the way of literature on this.  I have several journal articles looking at replacing various things in surgery.

J Arthroplasty. 2010 Sep;25(6 Suppl):75-80. Epub 2010 Jun 16.

Survivorship of polyethylene liner exchanges performed for the treatment of wear and osteolysis among porous-coated cups.


Anderson Orthopedic Research Institute, Alexandria, Virginia 22307, USA.


For the past 17 years, we have favored treating patients with polyethylene wear and osteolysis by performing a liner exchange with retention of the old shell when possible. Using our institutional database, we identified 187 acetabular revisions in which we had retained the old shell. Among this group, we found 25 rerevisions. These included 10 for hip instability, 9 for cup loosening, 3 for recurrence of excessive wear or osteolysis, 2 for infection, and 1 for dissociation of the replaced liner. The need for rerevision varied with the different retained shell designs. We rerevised 17% of the total hip arthroplasties with old spiked shells, 21% with Arthropor shells, 13% with Triloc shells and 5% with Duraloc shells. Before making a decision to retain or remove a well-fixed old acetabular shell, we recommend consideration of the design's past track record and careful inspection of the condition of the existing shell.


Arch Orthop Trauma Surg. 2011 Nov;131(11):1591-600. Epub 2011 Jun 19.

Complete acetabular cup revision versus isolated liner exchange for polyethylene wear and osteolysis without loosening in cementless total hip arthroplasty.


Department of Orthopaedic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-Dong, Kangnam-Ku, Seoul 135-710, Korea.



Revision surgery in patients showing polyethylene wear and acetabular osteolysis without visible acetabular cup loosening involves the difficult decision of whether to revise only the liner or both the cup and the liner. The purpose of this study is to compare the outcomes of complete acetabular revision and isolated liner exchange in patients showing wear and osteolysis without loosening.


We evaluated 80 cases of revision surgery for polyethylene wear and osteolysis without cup loosening performed between October 1997 and December 2008. The cup revision group consisted of 45 patients who underwent a complete acetabular cup replacement, and the cup retention group consisted of 35 patients who underwent either an isolated liner exchange or a liner cementing procedure. Comparisons between the two groups were performed.


There were differences in femoral stem revision, estimated blood loss, and hospital stay. Other variables including complications, osteolysis progression, re-revision rate, clinical score, and satisfaction showed no differences between the two groups. There was one case of early loosening and subsequent re-revision surgery in the cup revision group, as well as one case of wear progression and liner dislodgement leading to complete re-revision of the acetabular component and femoral stem in the cup retention group.


We found no differences in acetabular osteolysis progression, fixation failure, or complication between the cup revision and retention groups. Therefore, isolated liner exchange without cup extraction in cases of osteolysis that includes a well-fixed and well-positioned shell could be considered as a viable treatment option.


Orthopedics. 2010 Sep 7;33(9):650. doi: 10.3928/01477447-20100722-47.

Lysis in the well-fixed shell: "hold 'em" or "fold 'em".


Department of Adult Reconstruction and Joint Replacement, Hospital for Special Surgery, New York, New York, USA. sue@hss.edu


Periacetabular osteolysis is the greatest challenge for longevity of total hip arthroplasty. The generation of wear debris from the bearing surface is inevitably going to cause bone loss around the implants. The challenges for the arthroplasty surgeon in managing this problem are: detection, knowing when to intervene surgically, and choosing the best reconstructive option. From a surgical standpoint, the options for addressing osteolysis are: (1) liner exchange with or without bone grafting of lytic lesions; or (2) complete component revision. The advantages of "holding 'em" include a faster surgery, no bony disruption, a quicker recovery for the patient, and cost. The downside of isolated liner exchange is that there is a high rate of instability, there may be incomplete access to the lytic lesions, and the limitations of the existing component. There have been techniques developed to provide access to the retroacetabular lesions, particularly superolaterally via a trap-door technique. Alternatively, other surgeons have advocated injection of bone graft substitutes in the retroacetabular regions to fill osteolytic defects. However, one may not be able to take advantage of newer bearing materials, larger head sizes, or component reposition to improve stability and wear properties. The advantages of a complete component revision are access to lytic lesions, and the ability to modify component position and take advantage of newer technologies. The disadvantages are cost, a longer recovery, and bony disruption. Each method of addressing acetabular osteolysis has compelling reasons to use it; individual patient factors such as component type, size of lesion, and remaining bone will play a role in selecting the treatment


What I was unable to find was a surgery where the head or ball was just replaced.  This was in fact what was performed on the reader but there were unusual circumstances. I thought the case was interesting though.

Hope this helps albeit, none of the cases above are exact replications of your issues.



  1. Thanks for looking over my post op report and researching it. I wouldn't have known where to start looking. Thanks again for helping me to understand what was done. Good job, Connie.

  2. You are welcome! Look at the post tonite. i found some more interesting studies.