Highlighting the advantages and benefits of cementless total knee arthroplasty (Review)

Inferior short-term survivorship and patient outcomes for cementless compared to hybrid fixation with a cemented femoral implant in a novel blade-anchored medial unicompartmental knee arthroplasty design: An analysis of 132 cases

PURPOSE

For younger, more active patients, a cementless unicompartmental knee arthroplasty (UKA) might be more advantageous than cemented fixation. Therefore, this study aimed to compare implant survivorship and patient-reported outcome measures (PROMs) between cementless and hybrid fixation (cemented femur and cementless tibial fixation) in a novel tibial blade-anchored, medial UKA design.

METHODS

Two surgeon's registries were reviewed for patients who underwent primary cementless or hybrid medial UKA for medial osteoarthritis between 2019 and 2022. Patients were included if implant survivorship and one-year postoperative PROMs (UCLA-activity score, Oxford Knee Score (OKS), Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS-JR), pain (VAS) and satisfaction) were registered. Variables were compared using independent two-sample t-tests or the Chi-square test. Survival rates were determined using the Kaplan-Meier models and compared using the Log-rank test.

RESULTS

A total of 132 knees were included (cementless 58.3%; cemented 41.7%; mean follow-up 3.1 ± 0.6 years). Three-year all-cause revision survival rate was significantly superior for the hybrid fixation (hybrid: 100%; cementless 88.5%[84.7%-92.3%], p = 0.026). However, the difference in three-year conversion rate to total knee arthroplasty (TKA) did not reach statistical significance. The one-year postoperative OKS (hybrid: 42.9 ± 4.8; cementless: 39.8 ± 6.4, p = 0.003) and KOOS-JR (hybrid:81.5 ± 13.7; cementless: 74.4 ± 12.1, p = 0.002) were significantly superior for the hybrid fixation. Three-year conversion rate to TKA and two-year postoperative PROMs did not significantly differ.

CONCLUSION

The cementless medial UKA demonstrated a significantly inferior short-term all-cause survival rate and inferior postoperative one-year OKS and KOOS-JR compared to the hybrid medial UKA design with a cemented femoral component.

Cementless fixation in total knee arthroplasty: current evidence and future perspective

INTRODUCTION

Cementless fixation plays an increasing role in total knee arthroplasty (TKA). The objective of this review article is to analyze functional outcomes and survivorship of cementless TKA.

MATERIALS AND METHODS

A comprehensive literature search for studies reviewing the outcome and survivorship of cementless TKA was conducted. This search was based on the PRISMA 2020 guidelines using PubMed, Medline, and Embase. The included studies were screened by two independent observers.

RESULTS

From 2010 to 2022, fifteen studies were included. Eleven studies compared cementless and cemented TKA. Four studies only covered cementless implants. Survivorship and functional outcomes of cementless TKA are at least comparable to those of cemented implants.

CONCLUSION

With improvement in manufacturing, and surgical tools for more precise delivery, such as robotic assisted TKA and 3D-printed implants, one can expect increase in usage of cementless TKA, due to a more biological fixation, better survivorship, and outcomes.

Computational biomechanical study on hybrid implant materials for the femoral component of total knee replacements

Multifunctional materials have been described to meet the diverse requirements of implant materials for femoral components of uncemented total knee replacements. These materials aim to combine the high wear and corrosion resistance of oxide ceramics at the joint surfaces with the osteogenic potential of titanium alloys at the bone-implant interface. Our objective was to evaluate the biomechanical performance of hybrid material-based femoral components regarding mechanical stress within the implant during cementless implantation and stress shielding (evaluated by strain energy density) of the periprosthetic bone during two-legged squat motion using finite element modeling. The hybrid materials consisted of alumina-toughened zirconia (ATZ) ceramic joined with additively manufactured Ti-6Al-4V or Ti-35Nb-6Ta alloys. The titanium component was modeled with or without an open porous surface structure. Monolithic femoral components of ATZ ceramic or Co-28Cr-6Mo alloy were used as reference. The elasticity of the open porous surface structure was determined within experimental compression tests and was significantly higher for Ti-35Nb-6Ta compared to Ti-6Al-4V (5.2 ± 0.2 GPa vs. 8.8 ± 0.8 GPa, p < 0.001). During implantation, the maximum stress within the ATZ femoral component decreased from 1568.9 MPa (monolithic ATZ) to 367.6 MPa (Ti-6Al-4V/ATZ), 560.9 MPa (Ti-6Al-4V/ATZ with an open porous surface), 474.9 MPa (Ti-35Nb-6Ta/ATZ), and 648.4 MPa (Ti-35Nb-6Ta/ATZ with an open porous surface). The strain energy density increased at higher flexion angles for all models during the squat movement. At ∼90° knee flexion, the strain energy density in the anterior region of the distal femur increased by 25.7 % (Ti-6Al-4V/ATZ), 70.3 % (Ti-6Al-4V/ATZ with an open porous surface), 43.7 % (Ti-35Nb-6Ta/ATZ), and 82.5% (Ti-35Nb-6Ta/ATZ with an open porous surface) compared to monolithic ATZ. Thus, the hybrid material-based femoral component decreases the intraoperative fracture risk of the ATZ part and considerably reduces the risk of stress shielding of the periprosthetic bone.

Cementless TKA use as an alternative to cemented TKA in high BMI patients: A systematic review and meta-analysis

Purpose

Obesity is prevalent, with nearly one-third of the world's population being classified as obese. In patients with high body mass index (BMI)/body mass undergoing total knee arthroplasty (TKA), there is an increase in strain placed on the implant fixation interfaces. As such, component fixation is a potential concern when performing TKA in the obese patient. To address the growing concerns around the longevity of implant fixation, some have advocated cementless over cemented fixation. However, there is no clear consensus on whether a cementless fixation has more favourable outcomes. The aim of this paper was to present a systematic review and meta-analysis of the existing evidence to establish if cementless TKA has a lower rate of aseptic loosening in high BMI patients when compared to cemented TKA procedures.

Methods

A systematic review was performed, and the following databases Medical Literature Analysis and Retrieval System Online (1946 to date), PubMed (1966 to date) and Excerpta Medica Database (1974 to date) were searched. All studies comparing cementless to cemented TKA in patients with BMI > 30 were considered. Meta-analysis compared aseptic loosening and all-cause revision between cemented and uncemented implant use in BMI > 30 patients.

Results

The search returned 91 articles in total; after duplicates were removed, the yield was 44 studies. Of the remaining studies that were assessed, three studies met the inclusion criteria for meta-analysis. The pooled odds ratio for all-cause revisions was 0.17 (95%, 0.08-0.36) in favour of uncemented implants (p < 0.01). The pooled odds ratio for aseptic loosening was 0.15 (95% confidence interval, 0.02-0.90) in favour of uncemented implants (p = 0.04).

Conclusions

Meta-analysis demonstrated a significant decrease in all-cause revisions and revisions for aseptic loosening when using uncemented fixation in high BMI patients when compared to the use of cemented implants.

Level of Evidence

The level of evidence is 1 for our systematic review.

Survivorship and complications of cementless compared to cemented posterior-stabilized total knee arthroplasties: A systematic review and meta-analysis

PURPOSE

Controversy exists on the best fixation for total knee arthroplasty (TKA). Non-cemented fixation has been theorized to improve patient outcomes and longevity of implantation but no study has focused on comparison between cemented or cementless posterior-stabilized implants despite being the most commonly or second most frequently utilized implant in most total knee replacement registries.

METHODS

Inclusion criteria with observational and interventional papers, and review articles that focused on patients with cementless and cemented PS TKAs were used to analyze outcomes such as implant survivorship, complication, or revision rates. Using a combination of keywords, a systematic search was performed on Medline (PubMed), Embase, and Cochrane Library for Meta-Analysis.

RESULTS

When using the specified criteria, only 8 studies were selected for full-text analysis and meta-analysis after eliminating screening duplicates, titles, and abstracts without full-text access. These eight studies contain 1652 patients, 693 in the non-cemented Group, and 959 in the cemented total knee prosthesis Group. The meta-analysis revealed the advantage of cementless fixation over cemented fixation in implant survivorship, with 0.6% and 2.6% of aseptic loosening in each Group. The cumulative survival at 12 years was 97.4% for the cementless Group and 89.2% for the cemented Group. The subgroup with a stem showed a positive outcome for cementless fixation over cemented fixation regarding implant survivorship. No differences between the cemented and cementless TKAs were observed in patient-reported outcomes, revision rates, or radiolucent line development.

CONCLUSION

We observed comparable rates for cemented and cementless posterior-stabilized TKAs over a medium-term follow-up period.

24-Year-Old Patient with Klippel-Trenaunay Syndrome Underwent Cementless Robotic Cruciate-Retaining TKA: A Case Report

CASE

A 24-year-old man with Klippel-Trenaunay syndrome (KTS) presented with severe knee osteoarthritis unresponsive to conservative measures. Owing to end-stage, debilitating arthritic symptoms, surgery was pursued. Careful preoperative, multidisciplinary planning/treatment included magnetic resonance imaging to characterize the venous malformations throughout the right lower extremity, preoperative sclerotherapy, sirolimus, and robotic-assisted cementless total knee arthroplasty (TKA).

CONCLUSION

Cementless robotic-assisted TKA with selective patellar resurfacing can be a viable option for young KTS patients with severe osteoarthritis when a meticulous multidisciplinary approach, including sclerotherapy and advanced imaging, is undertaken to analyze vascular abnormalities, minimize surgical risks, preserve bone stock, and optimize outcomes.

Gap patterns and radiographic follow-up of newer-generation cementless total knee arthroplasty designs

BACKGROUND

Interest in cementless total knee arthroplasty (TKA) has increased with advancement of biomaterials and implant design and associated improved longevity. We sought to evaluate the gap patterns and radiolucent zones radiographically for 2 newer-generation cementless TKA designs.

METHODS

We retrospectively reviewed our single-institution database between January 2017 and December 2019. We identified patients with a porous keeled tibia base-plate with 4-bullet cruciform spikes and peri-apatite coated femoral component (study group 1) and patients who received a cementless porous coated femoral component and rotating platform tibia baseplate with 4 peripheral porous coated pegs around a central cone (study group 2). We identified gap patterns at 6 weeks and at 1 year or more postoperatively on radiographs, noting indications for reoperation.

RESULTS

We identified 228 patients in study group 1 and 41 patients in study group 2. At 1-year follow-up, we found evidence of resolved femoral gaps in 52 (72.2%) of 72 patients in study group 1 and 10 (58.8%) of 17 patients in study group 2 (p = 0.124). We identified 27 (84.3%) of 32 patients in study group 1 and 7 (70.0%) of 10 patients in study group 2 with resolved tibia gaps (p = 0.313). After 1 year, there were significantly more Zone 3a femoral zonal radiolucent gaps (p = 0.001) and Zone 8 tibia zonal radiolucent gaps (p = 0.002) in study group 2 than in study group 1. There were 4 reoperations for study group 1 and 0 reoperations for study group 2.

CONCLUSION

The modern cementless TKA systems have varied gap patterns in postoperative radiographs, which may be attributed to the implant design. Most radiolucent gaps resolve radiographically on follow-up.

Medial pivot design does not yield superior results compared to posterior-stabilised total knee arthroplasty: a systematic review and meta-analysis of randomised control trials

PURPOSE

The aim of this meta-analysis was a comparison between medial pivot (MP) and posterior-stabilised (PS) knee designs regarding functional and radiological outcomes as well as gait parameters.

METHODS

A systematic literature search was conducted in PubMed, Cochrane Library, Science Direct and Clinical Trials.gov from conception up to April 2022, to identify eligible randomised control trials (RCTs). The extracted data were analysed according to the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) statement.

RESULTS

Fifteen studies met inclusion criteria, enrolling 1101 patients who underwent 1242 total knee arthroplasties (TKAs). A total of 1158 TKAs (581 MP/577 PS) were included in the quantitative analysis. Mean follow-up ranged from 6 months up to 6.6 years. MP knees showed comparable range of motion (ROM) with PS design 1, 2 and 4 years postoperatively (p = 0.2, p = 0.25, p = 0.34, respectively). No statistical difference was found in patient-related outcome measures (PROMs) (p > 0.05). Mean walking speed (MWS), length of stay (LOS), radiographic alignment and complications rates were also similar between the two groups (p > 0.05).

DISCUSSION

The present meta-analysis demonstrated that the theoretical biomechanical advantage of MP implants does not have a better impact on patient satisfaction compared to the traditional PS knees.

LEVEL OF EVIDENCE

I.

A TEN-YEAR FOLLOW-UP AFTER CEMENTLESS TOTAL KNEE ARTHROPLASTY IN COUNTY GENERAL HOSPITAL

The aim of this long-term retrospective study was to evaluate the outcome of 109 cementless total knee arthroplasties performed in 101 patients at the General Hospital Bjelovar from January 2010 to October 2012. The survivorship of endoprosthesis and the clinical outcome were analyzed at the 10-year follow-up. The Oxford Knee Score was completed by 47% of patients with an average result of 31,2±9,4. There were two cases of aseptic loosening and one case of periprosthetic infection. Six patients suffered a periprosthetic fracture and were treated with osteosynthesis.