I think a registry is actually useful to look at this question. If you look at the Australian Registry, you see the cemented utilization going up and the cementless utilization going down over time. At every time point—5 years, 10 years, 15 years—cementless revisions outnumber that of cemented revisions.
Whether using a PS implant, CR implant, medial pivot implant, cementless fixation performs inferiorly at 1 year, 3 years, 5 years, and even 17 years to the point where the conclusion was basically cementing the tibial component gives the best outcome for minimally stabilized and medial pivot design prostheses (AOANJRR Annual Report 2018).
If you move next door to New Zealand, cementless fixation performed inferiorly compared to cemented fixation. Again, the comparison was that tibial loosening was the main culprit for an increased revision rate in this cohort of patients (The New Zealand Joint Registry Annual Report 2017).
Other countries such as Scandinavia showed no increase in cementless fixation utilization (Swedish Knee Arthroplasty Registry Annual Report 2016). Maybe because cementless fixation is associated with increased risk of all causes of revision, increased risk of pain, increased risk of aseptic loosening (National Joint Registry 13th Annual Report 2016). Higher revision rates at every point even beyond 10 years, which is when you would expect the curves to simply diverge if cemented fixations were also going to fail at that time. And they’re not really…the curves are essentially parallel in terms of survivorship.
There’s no doubt that improved designs and reliability make cementless fixation viable, but I would propose that just because commercial space travel is viable, doesn’t necessarily mean I’m going to do it. All these studies show comparative performance and not superior performance (Pulido, et al., CORR, 2014; Harwin, et al., JOA, 2017).
This is an older study. The 5-year results were actually presented at AAHKS, again, showing no difference in clinical outcome scores. No difference in survivorship. And the cementless group had more radiolucent lines (Fricka, et al., JOA, 2015).
In a study also presented at AAHKS that was subsequently published showed that cementless fixation doesn’t decrease operative time. Doesn’t decrease blood loss. And doesn’t decrease a change in hemoglobin. This was actually interesting as the cementless group had a higher patient satisfaction compared to the cemented group (Nam, et al., JOA, 2017).
Meta-analysis showed no difference between cemented and cementless fixation in total knee arthroplasty even in the young patients (Franceschetti, et al., Knee Surg Sport Traumatol Arthrosc, 2017), albeit I’ll admit the level of evidence is relatively low.
Michael alerted us that basically he can’t necessarily use these in every patient population. Many of our patients are obese and early tibial failure has been reported in this cohort of patients (Meneghini, et al., JOA, 2013).
Some studies have not necessarily found these differences…very short-term studies…but other studies following these patients out to a longer term clearly see a difference in survivorship compared to non-obese individuals (Boyle, et al., JOA, 2018; Lizaur-Utrilla, et al., JOA, 2014).
I think he shared some of the RSA data. In terms of mobility, cementless total knee arthroplasties move more than cemented total knees early on, within the first 2 years. I think the difference is beyond the 2 to 5 years (van Hamersveld, Bone Joint J, 2017).
Clearly you should not use this on every patient. Bone quality matters (Andersen, et al., JOA, 2017).
