Cemented hip implants still relevant despite low use
Click Here to Manage Email Alerts
Popularized by Sir John Charnley, MB, ChB, MRCS, LRCP, in the 1960s, total hip arthroplasty with a cemented femoral component was the standard of care for surgical treatment of osteoarthritis for several decades.
However, as cemented implant designs increased, so did failure rates.
Source: UVA Health
“As cement designs proliferated and surgeons and manufacturers came up with different implant designs and techniques, there were some designs that worked well and others that did not,” William G. Hamilton, MD, of the Anderson Orthopaedic Clinic, the Anderson Orthopaedic Research Institute and fellowship director of the Anderson Postgraduate Medical Education Foundation, told Healio | Orthopedics Today. “That led to a fair number of cases where cement fixation failed, which required revision surgery, and a revision of a failed cemented implant was in many ways more complicated than a loose cementless implant.”
Although cementless femoral component fixation was introduced in the 1980s, Hamilton said it remained an outlier until the 1990s to 2000s. As data demonstrated the success of various cementless THA implants, the use of cemented THA decreased, according to Hamilton.
“Cementless fixation is an attractive option for surgeons for a few reasons. It makes the procedure faster and more predictable, and when bony ingrowth is achieved it is likely more durable than cemented implants in the long run,” Hamilton, a Healio | Orthopedics Today Editorial Board Member, said.
Need for biologic interface
In addition to being more efficient compared with cemented THA, James A. Browne, MD, professor of orthopedic surgery at the University of Virginia, said one of the reasons why cementless THA became the mainstay in North America was due to the desire to have a biologic interface and improve the longevity of fixation, particularly in young patients.
“The use of cement is a great way to anchor a component into the bone, but it is a mechanical method of fixation and, over time, it can loosen and fail,” Browne said. “A biologic method of fixation is more dynamic, [and] it can theoretically last forever. Once an implant becomes biologically fixed to the patient, it can be permanent, unlike when an implant is mechanically fixed with cement.”
Cement embolization and cement implantation syndrome can also be risks associated with cemented THA, according to sources.
“In older patients, and particularly femoral neck fracture patients, there is a risk of what is called cement implantation syndrome, which relates to fat embolization at the time of surgery, which can cause death,” Daniel J. Berry, MD, L.Z. Gund professor of orthopedic surgery at the Mayo Clinic, told Healio | Orthopedics Today. “It is a serious problem. It is fortunately rare and there are ways to mitigate it, but it is associated more with cemented implants than with uncemented implants.”
But Browne said he is skeptical about the risk of cement implantation syndrome.
“We do not know if it truly exists as a distinct clinical entity unique to cement, and if it does exist, it is exceptionally rare,” he said. “[Cement implantation syndrome] does not deter me from cementing when necessary.”
Cemented implants still relevant
Despite the decreased use, Berry said cemented hip implants “never went away.”
“In many places, it has been used regularly,” Berry said. “Ever since the advent of hip arthroplasty, the implants have advanced in terms of design and, in a lot of parts of the world, cemented femoral components never went away.”
Lower loosening and early periprosthetic fracture rates are the main reasons for the continued use of cemented hip implants, according to Joseph T. Moskal, MD, chair and professor of orthopedic surgery at the Virginia Tech Carilion School of Medicine. He said results published in 2023 from the American Joint Replacement Registry showed 25% of early hip revisions in the last decade are related to early fracture.
“Reoperating on somebody who just had a periprosthetic fracture had approximately a 45% to 60% complication rate, 5% to 15% infection rate. One-quarter of them will need another reoperation and at 1 year, the mortality rate is anywhere between 5% to 50%, which is a problem, in my opinion,” Moskal told Healio | Orthopedics Today.
When comparing cemented and cementless hip implants, Moskal said registry data have shown patients who receive a cementless hip implant had a higher revision rate at all time points, but specifically within the first 2 to 4 weeks postoperatively.
“If you look at the difference in the cumulative revision rate, the main reason is fracture and loosening,” Moskal said. “If you fracture, the components also loosen, and this effect is even greater in patients older than 75 years when you compare cemented vs. cementless. The cementless stems in patients aged 75 years or older have a nine times greater likelihood of needing to be revised just in the first month.”
Patients who benefit
There are also specific subpopulations of patients who have better outcomes with cemented hip implants, according to Berry. Although much depends on the patient population and database reviewed, Berry said patients aged older than 75 years, particularly women, and patients with poor bone quality tend to have better outcomes with cemented hip implants.
“The main reason uncemented implants do not do as well in that group is related to two factors: one, and most importantly, is a higher risk of early periprosthetic femur fractures associated with loosening of the implant in that group of patients,” Berry said. “In other words, they are at risk for early fracture of the bone, which leads to loosening of the implant or just loosening of the implant. Probably both are related to bone quality issues and maybe a little bit due to the risk of falls.”
Moskal said patients with hip fractures also should be considered for a cemented hip implant.
“Whether you are going to be doing a total hip or a hemiarthroplasty for those patients, I think those patients warrant strong consideration for a cemented stem because the femur is already broken and most likely the fracture occurred with minimal force or effort,” Moskal said. “We know that for patients with femoral neck fractures at 1 year they already have a high mortality rate. Some folks report up to 30%. You want to do one and done with those patients and minimize the likelihood of them having another fracture or requiring another reoperation.”
Modest increase
As research shows improved outcomes in specific subpopulations of patients, sources who spoke with Healio | Orthopedics Today said there has been an increase in the use of cemented hip implants, albeit a modest one.
“If we go back looking at the American Joint Replacement Registry around 2012, the utilization of cemented total hips in [North America] was about 2.8%. And during the last 10 years, that number has increased, but albeit only modestly to 4.6%,” Moskal said. “If you want to accentuate the positive, there has been an increased popularity of it. But based on our joint registry, we can see that still almost 95% of elective total hips in this country are cementless.”
R. Michael Meneghini, MD, CEO at the Indiana Joint Replacement Institute and professor of clinical orthopedic surgery at the Indiana University School of Medicine, said the increase in the use of cemented hip implants may also be due to the popularity of the direct anterior approach, which is used in more than 50% of cases. However, he said the direct anterior approach does not allow the surgeon to visualize the femur well and is associated with an increased risk of periprosthetic femur fractures compared with the posterior approach.
“When you have an approach where you cannot see the femur well, sometimes it is easier to cement [the implant] in rather than try and impact it in with an uncemented device,” Meneghini, a Healio | Orthopedics Today Editorial Board Member, said.
Lack of training
However, because most hip implants being used in North America during the past 2 decades have been cementless, surgeons trained in that timeframe became more comfortable with cementless implants than cemented implants, according to Browne. This had led to a concern that surgeons are no longer being adequately trained in using cemented femoral components.
To identify whether this is the case, J. Conner Ryan, MD, Browne and colleagues conducted a survey of orthopedic residents who were about to graduate and go into practice about their experience using cemented and cementless stems during training. Results showed 37% of residents found their training in cemented hip arthroplasty to be comprehensive or very comprehensive, with 17% of residents reporting inadequate or nonexistent training in cemented technique. Researchers found 40% of residents reported being less than satisfied with their training, and there was a correlation between feeling prepared to perform a well-done cemented femoral stem with higher percentage of cemented stems in training and higher satisfaction with training. According to Browne, 96% of residents felt comfortable with cementless fixation, whereas 82% of residents felt adequately trained in cemented fixation.
“We do not educate well when it comes to cemented fixation. We do not do enough of it. We do not train on the technique and, as a result, surgeons who are coming into practice do not feel as comfortable with this technique compared to cementless fixation,” Browne told Healio | Orthopedics Today.
Better education
With the move toward an increased use of cemented femoral stems, Browne said it is important for surgeons to be able to perform cemented hip arthroplasty well. If not performed well, he said “the consequences of a poorly done cemented femoral component can be just as bad, if not worse, than a fracture.”
“As many of us advocate for an increased use of cemented femoral components, we do have to be cognizant of the fact that many of the surgeons who are coming into practice do not have a great experience training with that technique,” Browne said.
Since the publication of the study, Browne said there have been discussions on “how to fix the problem,” with the biggest concern focused on residents who do not complete a fellowship.
“A lot of the residents going out into practice that have not done a fellowship will be taking care of hip fracture patients and doing hip replacement procedures for fractures,” Browne said. “Those are the ones who are potentially the most vulnerable here to this problem.”
Other discussions have focused on improving the curriculum of orthopedic education, with proposals including a potential requirement for a certain number of cemented femoral components performed during residency for surgeons to graduate, according to Browne.
“It is hard to mandate certain things when it comes to training, but our hope in doing the research is at least we have shed some light on this problem. We hope that residency and fellowship programs will respond and increase the exposure to cemented femoral stems,” he said.
Improved uncemented implants
Despite the role cemented hip implants have in the treatment of older patients with poor bone quality, Berry said improvements are being made in uncemented hip implants that may help with this patient population.
“As the problem of periprosthetic fracture related to uncemented implants in those older patients has been recognized, surgeons have started to figure out strategies to make uncemented implants perform better. And the gap between how uncemented implants perform in those patients and cemented implants perform in those patients is closing,” Berry said.
According to Berry, research has shown collared triple-taper uncemented stems may reduce the risk of loosening and periprosthetic femur fractures, even among older patients. Similarly, he said use of prophylactic cerclage wire around the proximal femur may also reduce the risk of fracture.
The addition of smart sensors to pneumatic inserting devices may help predict when a bone might fracture and allow surgeons to use more uncemented devices in older patients, according to Meneghini.
“The elderly patients are the ones whose lungs are not as resilient, and they are the ones you do not want to spray their lungs with embolization from a cemented femoral component,” Meneghini said.
As cementless hip implants continue to be improved, Browne said more research is also needed on specific designs of cemented components.
“There are some emerging data that suggest certain cemented stem designs may have a lower risk of fracture compared to others,” Browne said. “Looking at taper slip designs vs. composite beam or collared cemented designs will help us even further reduce the risk of periprosthetic fractures.”
Randomized studies needed
While some level-1 data exist on cemented hip implants, Browne said, “the more randomized studies we can get, the better,” especially studies comparing cemented and cementless hip implants.
“The problem with a lot of the observational data and the registry data is that it is potentially confounded,” Browne said. “Patients who are sicker, less healthy and have poor bone, tend to be the patients who get cemented components. More randomized studies are what we need to tease out the effect size.”
As more research is conducted on cemented hip implants and as the population continues to age, Moskal said he is optimistic that use of cemented hip implants will continue to increase. However, implant choice still requires careful patient selection by reviewing patient morphology and clinical history, as well as a “humble appreciation for the data that are being reported in our peer reviewed literature,” according to Moskal.
“What we thought to be, in our opinion, an appropriate or prudent approach of always using a cementless stem may no longer be a prudent approach today,” Moskal said “Today, we have to be more thoughtful with regard to our stem selection. And I would hasten to say that there is no question that it is not black and white. At times, it may be prudent to use the cementless stem. But at times, it may not be prudent to use a cementless stem and it would be more judicious to use a cemented stem.”
- References:
- Heckmann ND, et al. J Arthroplasty. 2021;doi:10.1016/j.arth.2021.06.029.
- Maggs J, et al. Indian J Orthop. 2017;doi:10.4103/ortho.IJOrtho_405_16.
- Matthias J, et al. J Am Acad Orthop Surg Glob Res Rev. 2021;doi:10.5435/JAAOSGlobal-D-21-00014.
- Ryan JC, et al. J Arthroplasty. 2022;doi:10.1016/j.arth.2022.03.005.
- Satalich JR, et al. EFORT Open Rev. 2022;doi:10.1530/EOR-22-0002.
- Toci GR, e al. J Arthroplasty. 2022;doi:10.1016/j.arth.2022.03.086.
- For more information:
- Daniel J. Berry, MD, of the Mayo Clinic, can be reached at madson.rhoda@mayo.edu.
- James A. Browne, MD, of the University of Virginia, can be reached at jab8hd@uvahealth.org.
- William G. Hamilton, MD, of the Anderson Orthopaedic Clinic, can be reached at williamhamiltonmd@gmail.com.
- R. Michael Meneghini, MD, of the Indiana Joint Replacement Institute, can be reached at rm_meneghini@yahoo.com.
- Joseph T. Moskal, MD, of the Virginia Tech Carilion School of Medicine, can be reached at jtmoskal@carilionclinic.org.
Click here to read the Point/Counter to this Cover Story.
Collapse
Click Here to Manage Email Alerts