Dear Panayot

In revision hip arthroplasty usually the indication is loosening and often there is bone resorption . i think is much more frequent use of cemented total hip arthroplasty and the cementless endoprosthesis is an exception

Dear Nelson,

I agree with you. In many cases there are so big bone defects that the proper fitting of cementless endoprosthesis is really problematic. In my opinion one could try cemetless THR in selected patients, but the common cases need bone cement, eventually in combination with impaction osteoplasty, antiprotrusion acetabular cage or femoral canal mesh funnel.

Dear collegues,

I would prefer cemented hip prosthesis, although I think in some cases where you can doubt it´s reasonable to ask for a gammagraphy and see which component it´s affected. If acetabular component doesn´t show any activity and the problem is just the femoral and if the patient has high conmorbidity I think it would be preferible to change only the femoral component with a cemented prosthesis. The critical key it´s to maintain a correct position of the prothesis in the femoral canal.

Dear Dr. Vinagre,

You are right as far as the preoperatrive decision making and planning are concerned. The gammagraphy which you recommend could be helpful too. However, the last decision which component to exchange and which to leave in situ unchanged, is decided during the operation when you "ad oculo" can test the stability. It is not a rare case to replace only the acetabular cup or only the femoral part.Some problems appear in similar cases with long standing THR (20-30 years from the primary replacement) when a compliant new component is to be implanted (i.e. head diameter, neck conus, etc.). Unfortunately, in rare cases we have to replace even a well fixed component for that reason.

Dear panayot Tanchev,

I would like to give some literature about your question,thanks for your question .

Many concepts have been devised for the treatment of late periprosthetic infections of total hip prostheses. A two-stage revision with a temporary antibiotic-impregnated cement spacer and a cemented prosthesis appears to be the most preferred procedure although. (reference:Revision of late periprosthetic infections of total hip endoprostheses: pros and cons of different concepts.Fink B.

Int J Med Sci. 2009 Sep 4;6(5):287-95. Review)

Primary total hip arthroplasty (THA) is one of the most effective procedures for managing end-stage hip arthritis. The burden of revision THA procedures is expected to increase along with the rise in number of primary THAs. The major indications for revision THA include instability, aseptic loosening, infection, osteolysis, wear-related complications, periprosthetic fracture, component malposition, and catastrophic implant fracture. Each of these conditions may be associated with mild or advanced bone loss. Careful patient evaluation and bone loss classification guide preoperative planning and overall patient care. Historically, uncemented fixation has provided the best results, but cemented fixation is required in some cases. (Reference:J Am Acad Orthop Surg. 2013 Oct;21(10):601-12. doi: 10.5435/JAAOS-21-10-601.

Femoral bone loss in revision total hip arthroplasty: evaluation and management.

Sheth NP, Nelson CL, Paprosky WG.)

There is an increasing trend towards cementless modular femoral prostheses for revision hip replacement surgery, especially in patients with severe proximal femoral bone defects. However, for minor femoral bone defects, the benefit of cementless modular is not clear. We designed a retrospective cross-sectional study to compare outcomes of the two femoral implant designs. There were no significant differences in terms of visual analog pain scores, Harris hip scores, femoral bone restoration, stem subsidence, leg length correction, or overall complication rate. Three femoral reoperations (11%) occurred in the cemented group, and two (9%) in the cementless modular group. One femoral stem re-revised (4%) in the cemented group due to recurrent deep infection. Five-year survival for femoral reoperation was 88.2% for patients with the cemented implant and 91.3% for cementless group. Both groups had good clinical and radiological outcomes for femoral revision in patients with minor femoral bone defects during medium-term follow-up. (Reference:Sci Rep. 2013 Sep 30;3:2796. doi: 10.1038/srep02796.Medium-term outcomes of cemented prostheses and cementless modular prostheses in revision total hip arthroplasty.Wang L, Lei P, Xie J, Li K, Dai Z, Hu Y.).

The quality of cementation was identified as a significant risk factor for further loosening. Revision total hip replacement using a cemented long femoral component yielded satisfactory long-term results in this series.(Reference:Arch Orthop Trauma Surg. 2013 Jun;133(6):869-74. doi: 10.1007/s00402-013-1733-6. Epub 2013 Apr 13.

Revision total hip replacement with a cemented long femoral component: minimum 9-year follow-up results.

So K, Kuroda Y, Matsuda S, Akiyama H.

Uncemented distal locked prosthesis provide adequate stability in revision THA, aiding the reconstruction of bony deficiencies while avoiding the disadvantages of fully porous or cemented implants.(Reference:Indian J Orthop. 2013 Jan;47(1):83-6. doi: 10.4103/0019-5413.106918.

Results of uncemented distal locked prosthesis in revision hip arthroplasty with proximal femoral bone loss: A retrospective study.

Agarwala S, Jhunjhunwala HR, Pachore JA, Joglekar SB, Eachempati KK.)

Long-stem cemented revisions for aseptic loosening in elderly patients allow immediate postoperative weight bearing and have good radiological and clinical outcomes.(Reference:Hip Int. 2013 Jan-Feb;23(1):54-9. doi: 10.5301/HIP.2013.10615.

Long stem cemented revision arthroplasty for aseptic loosening in elderly patients produces good results, despite significant bone loss.

Harrison T, Wynn Jones H, Darrah C, Warriner G, Tucker JK.)

Respectfully Yours.

Thank you, Dr. Kemal. The information in your answer is very valuable. I must admit I am a "bone cement friend". Our results are also good at 5-year follow-up.

I agree with you and the data given by Agarwala et al. as far as the application of uncemented distally locked femoral component in cases with major proximal bone loss is concerned. In similar cases we use long revisional uncemented stems with osteoplasty proximally.

Panayot,

From a hip designers point of view your question "What do you prefer in revision hip surgery" lends itself to regional replays. I have found with over 40 years in the development of hip devices the preference is based significantly by region or country of experience. Here in the United States since the 1980s the trend has moved from cemented to cementless devices. Two specific devices have helped move that trend "the AML and the S-Rom stem".

The fully porous coated cylinder design of the AML allowed one to bypass the proximal bone loss and go for distal fixation. As part of the S-Rom development team we  created a modular system of sleeves to address proximal bone loss with a distal fluted stem that provided distal torsional stability with out the concerns of distal fixation resulting in proximal stress shielding.

Rotary or severe angular deformities, and the occasional revision which requires retrieval of a fully porous coated implant, are treated by femoral osteotomy. The sleeve can be securely fixed in the proximal host bone at the orientation

that best fits the bone. The stem is inserted into the taper lock sleeve and the proximal bone. This combination is then implanted in the distal bone, where the fluted stem provides rotational stability. The same situation pertains where massive bulk allografts of the proximal femur are used. The proximal stem and sleeve may

be attached to the allograft by means of bone cement. The junction between the allograft and host bone is cementless along with the fixation of the distal portion of the stem.

One of the main difficulties in hip surgery is conversion or retrievability of implants. Any implant inserted into a young person may fail in time. if the fixation does not loosen or the implant does not break, then the plastic bearing will eventually wear out. It is desired, therefore, that revision should be possible with minimal bone destruction. To minimize chances of distal osteointegration, i.e., direct apposition of the bone to the distal stem, the distal portion of the stem is highly polished. A stem can be separated from the sleeve by means of wedges and the hip

retrograded with a slaphammer. Ready access to the proximal sleeve then permits loosening with flexible osteotomes or a high-speed burr and removal in retrograde fashion with a proximal sleeve extractor and slap-hammer.

The overall success of the S-Rom Stem system has encouraged the development of a number of additional cementless stems over the years and I would say over 90% of all revisions in the United States are now done with cementless technology.

Another factor to take into consideration is current training in our Residency programs. Since there is so little cemented revision surgery being done in the United States, I believe we are losing the expertise to train and perform revision cemented surgery. That is a concern because I for one believe a hip surgeon should be familiar with all possible techniques and there is still indication for the use of bone cement.

I won't bother attaching any publications in support of my answer since the literature is flooded with references.

Thank you, Timothy, for your answer.

To remove bone cement from the femoral canal is a big trouble at revision. I may only guess that one of the reasons for the trend to cemetless primary THR is so strong nowadays, because of the misgivings related to the difficulties when perfomimg revisional THR after years.In any case, to think of a second line of defence is a good idea.With regard of the revisional THR, I think the best choice  is made by the surgeon himself/herself based upon the personal experience and the individual case.  

Panayot,

You correctly state removal of cemented stems or for that matter well fixed distal cementless stems can be problematic if removal is needed. Partially for that reason short curved neck preserving stems have been coming on the scene especially with the success of professor Pipino's work. Since the 1980s many of us have slowly begun to advocate the use of shorter stems in an attempted to save bone in case of revision surgery. I have been a follower of Pipino and Freeman in their selection of saving the femoral neck to reduce both bending and torsional forces. Freeman advocated a straighter stem style while Pipino has advocated a short curved stem. This is more to my liking because there is no need to go lateral into the trochanteric bed. The curve of the stem follows the natural medial curvature of the femur and reduces intraoperative blood loss and can place more compressive loads onto the medial calcar.

If stem removal is necessary you can removal with minor bone loss converting to a standard length cementless stem. I have attached a recent poster presented this past June from EFORT for your review. I believe we will see more interest in short stem technology.

Regards,

Tim

Conference Paper The Science Behind a Short (Neck Preserving) Curved Stem Tot...

Dear Timothy, thank you for your answer and the attached abstract too. You mention also  the reduced number of resurfacing hip arthroplaties at present. I am a witness of the enthusiasm of implanting the Wagner cup arthroplasty in the 70's. In our experience they (30 cases) all failed in 1-3 years postoperatively (loosening, avascular head necrosis, neck fracture,etc) and this prosthesis was abandoned. I make an analogy with the Smith-Petersen cup arthroplasty (40's) that also failed. I wonder how techniques and designs move along an ondulating curve of enthusiasm and oblivion.

The list of advantages of the curved short-stem in your abstract is really impressive. In fact there is an avalanche of short-stem prostheses at present . Fetto' s biomechanical  theory and "lateral flare" stem design for force  transduction from the hip joint onto the femoral bone, where the metaphysis (greater trochanter) will take up the major part of loading by elimination stress risers seems to be also reasonable. But  I find some sort of controversy with the requirement to avoid going laterally towards to the trochanter bed when using a short curved stem (Pipino). Which design is more stable ? Furthermore, I believe there are still lacking long-term results using short stems proving their advantages in comparison with the traditional stems.                                                                                                                                     

Panayot,

I could not agree with you more. I to have been around since the 1970s and remember very well the failures of the first generation and second generation hip resurfacing devices. If we look at the current success of these devices we find a very long learning curve and a very narrow indication. The problem with new emerging technologies is just that "learning curve and true indications". You can generally find surgeon inventors have a good understanding of the required technique to make their devices work. The problems come into play as the devices becomes available to a larger surgeon market place.

The device industry wants to get their technology into the market ASAP. 

A slow introduction of new technology is called for and we need to encourage early reporting of these findings. Currently the surgical pearls of case reports are getting harder to publish. Many journals do not want manuscripts unless there is two year results. We should see early clinical/surgical impressions and we should be encouraging early publications on complications and contraindications.

I also remember well the use of Uni compartmental knees in the 1970s. We saw the failure of 6 mm tibial Marmor knees fail partly due to the thinness of the tibial poly component, only to find a resurgence of the uni knee 30 years later. Why did the market place think a 6 mm poly tibial component would work today when it did not in the 70s?

I believe there is a market place for narrow indications for specific designs but we need to be as clear as possible on indications.

Example is short stem technology for hip replacement . There are a variety of different design concepts like Joe Fetto's lateral flare  stem versus Pipino's short curved neck sparing stem. Comparing these two stems and then making a broad statement on short stems is unfair. There needs to be a stem classification system that allows us to compare different designs to determine proper indications and contraindications.

I also agree with your comment that long term data is not available on most short stem designs. The exception being Pipino's work which is now over 30 years. I am attaching a couple of recent papers for your review and welcome your feedback.

Regards,

Tim

Conference Paper The Science Behind a Short (Neck Preserving) Curved Stem Tot...

Conference Paper Short Stems in Total Hip Arthroplasty

Article Total Hip Stem Classification System

Thank you, Timothy, for your posting. Of course it is not correct to compare Fetto's and Pipino's designs. The concepts are different. On the other hand, they both belong to the short stems. And I still wonder which concept is better ? I think comparable RCT's are still not available and this is the problem.

Regards