A Systematic Review and Network Meta-Analysis of the Outcomes of Patients With Total Knee Arthroplasty Using Cemented, Uncemented, or Hybrid Techniques.

In this study, we aim to explore the differences among the three types of fixation methods for the components of the knee joint in patients who underwent total knee arthroplasty (TKA). These methods are cemented, uncemented, and hybrid fixation. Cemented fixation means that a special type of grout is used to attach the components to the bone. Uncemented fixation means that the components are designed to fit tightly into the bone and allow new bone growth to secure them. Hybrid fixation means that a combination of cemented and uncemented fixation is used for different components. We searched four online databases to find studies relevant to our research question. We use the R program (R Foundation for Statistical Computing, Vienna, Austria) for network meta-analysis (NMA) to analyze the data from the studies. We calculate the mean difference (MD) and the 95% confidence interval (CI) for each outcome, which are statistical measures of the difference and the uncertainty between methods. We use these measures for continuous outcomes, meaning they can have any value. For dichotomous outcomes, meaning they can only have two values, we use the risk ratio (RR) and the 95% CI, which are statistical measures of the relative risk and the uncertainty between methods. We assess the quality of randomized controlled trials, which are studies that randomly assign participants to different methods, using the Cochrane Risk of Bias Assessment Tool 1, a tool that evaluates the potential biases in the studies. We include 21 studies, and our analysis shows that cemented TKA reveals a statistically significant decrease in pain with hybrid TKA (MD = -2.82). That said, we find no significant differences between uncemented and cemented or hybrid (MD = -0.80 and -2.02, respectively). The results show that there is no significant difference between uncemented TKA and cemented TKA or hybrid technique (RR = 0.87, 95% CI 0.35-2.14; RR = 0.73, 95% CI 0.22-2.39, respectively). Also, we find no significant difference between cemented TKA and hybrid TKA (RR = 0.84, 95% CI 0.24-2.93). Cemented TKA is associated with a lower risk of deep vein thrombosis (DVT) incidence rate. Moreover, it shows a significant decrease in pain compared to hybrid TKA. Future research is needed to compare among the three interventions.

Cementless Total Knee Arthroplasty is Associated With Early Aseptic Loosening in a Large National Database.

BACKGROUND: Despite excellent longevity demonstrated in institutional studies, outcomes after cementless total knee arthroplasty (TKA) on a population level remain unknown. This study compares 2-year outcomes between cemented and cementless TKA using a large national database. METHODS: A large national database was used to identify 294,485 patients undergoing primary TKA from January 2015 to December 2018. Patients who had osteoporosis or inflammatory arthritis were excluded. Cementless and cemented TKA patients were matched one-to-one based on age, Elixhauser Comorbidity Index, sex, and year yielding matched cohorts of 10,580 patients. Outcomes at 90 days, 1 year, and 2 years postoperatively were compared between groups, and Kaplan-Meier analysis was used to evaluate implant survival rates. RESULTS: At 1 year postoperatively, cementless TKA was associated with an increased rate of any reoperation (odds ratio [OR] 1.47, 95% confidence interval [CI] 1.12-1.92, P = .005) compared to cemented TKA. At 2 years postoperatively, there was an increased risk of revision for aseptic loosening (OR 2.34, CI 1.47-3.85, P < .001) and any reoperation (OR 1.29, CI 1.04-1.59, P = .019) after cementless TKA. Two-year revision rates for infection, fracture, and patella resurfacing were similar between cohorts. CONCLUSION: In this large national database, cementless fixation is an independent risk factor for aseptic loosening requiring revision and any reoperation within 2 years after primary TKA.

Patient-reported outcomes following cemented versus cementless primary total knee arthroplasty: a comparative analysis based on propensity score matching.

BACKGROUND: Existing studies of patient-reported outcomes (PRO) following total knee arthroplasty (TKA) based on fixation methods (cemented vs cementless) are limited to single centers with small sample sizes. Using multicentered data,, we compared baseline and early post-operative global and condition-specific PROs between patients undergoing cemented versus cementless TKA. METHODS: With PROs prospectively collected through Comparative Effectiveness Pulmonary Embolism Prevention After Hip and Knee Replacement (PEPPER) trial (ClinicalTrials.gov: NCT02810704), we examined pre- and post-operative (1, 3, and 6-months) outcomes in 5,961 patients undergoing primary TKA enrolled by 28 medical centers between December 2016 and August 2021. Outcomes included the short-form of the Knee Injury and Osteoarthritis Outcome Score (KOOS-Jr.), the Patient-Reported Outcomes Measurement Information System Physical Health (PROMIS-PH), and the Numeric Pain Rating Scale (NPRS). To minimize selection bias, we performed a 1-to-1 propensity score matched analysis to assess relative pre- to post-operative change in outcomes within and between cemented and cementless TKA groups. RESULTS: With greater than 90% follow-up, significant pre to- post-operative improvements were observed in both groups. At 6 months, the cemented TKA group achieved a 3.3 point (55% of the Minimum Clinically Important Difference) greater improvement in the mean KOOS-Jr. (95%CI: 0.36, 6.30; P = 0.028) than did the cementless group with no significant between-group differences in PROMIS-PH and NPRS. CONCLUSIONS: In a large cohort of primary TKAs, patients with cemented fixation reported early incremental benefit in KOOS-Jr. over those with cementless TKA. Future studies are warranted to capture longer follow-up of PROs.

Cementing technique for total knee arthroplasty in cadavers using a pastry bone cement.

BACKGROUND: In cemented primary total knee arthroplasty (TKA), aseptic loosening remains a major cause for failure. Cementing techniques and characteristics of a chosen cement play a key role for good fixation and implant survival. A pastry bone cement was developed to facilitate the cement preparation and to rule out most of preparation-associated application errors. The pastry bone cement was compared to a conventional polymethyl methacrylate cement in a TKA setting. METHODS: Standardized implantations of total knee endoprostheses were performed in bilateral knee cadavers to investigate handling properties, variables of cement application, working time, and temperature development. Mechanical aspects and cementation quality were assessed by pull-out trials and microscopic interface analysis. RESULTS: Both cements expressed similar characteristics during preparation and application, only the curing time of the pastry cement was about 3 min longer and the temperature peak was lower. Fractures of the conventional cement specimens differed from the pastry cement specimens in the tibial part, while no differences were found in the femoral part. Penetration depth of the pastry cement was similar (tibia) or deeper (femur) compared to the conventional cement. CONCLUSIONS: The pastry cement facilitates the feasibility of cemented TKA. The pre-clinical tests indicate that the pastry bone cement fulfills the requirements for bone cement in the field of knee arthroplasty. A clinical trial is needed to further investigate the approach and ensure patient safety.

A matched cohort study between cementless TKA and cemented TKA shows a reduction in tourniquet time and manipulation rate.

INTRODUCTION: Cementless total knee arthroplasty (TKA) is now becoming more acceptable with the advent of newer ongrowth constructs and better initial fixation. It has been proposed that cementless TKA may save OR time and result in a lower incidence of manipulation. This study was designed to assess the difference between cemented and cementless TKA. METHODS: Our hospital statistician performed a matched cohort analysis between 127 cementless TKAs and 127 cemented TKRs performed by a single surgeon. Patients were matched on age and BMI. Mean tourniquet time between the cemented and cementless TKAs was assessed as well as the rate of manipulation between these groups. Of note, a tourniquet was routinely used in both the cementless and cemented cohorts to reduce confounding bias. RESULTS: A total of 127 cementless TKAs with a mean age of 60.8 years and mean BMI 32.2 were compared to 127 cemented TKAs with a mean age of 61.5 years and mean BMI of 32.2 at an average follow-up of 2.0 years. There was a statistically significant reduction in tourniquet time in the cementless TKA cohort at 45.7 min compared to the cemented TKA cohort at 54.8 min (p = 0.001). Estimated blood loss was similar in both the cementless (179.5 ml) and cemented (196 ml) cohorts (p = 0.3) and postoperative outcomes, including UCLA score.In addition, the cementless TKA cohort had a manipulation rate of 0% compared to 3.1% for the cemented TKA group (p = 0.044). DISCUSSION AND CONCLUSION: While cementless and cemented TKA have shown similar PROMs and survivorship, we demonstrated a significant reduction in tourniquet time with cementless TKRs, with similar estimated blood loss, and a lower incidence of manipulation with cementless TKRs in this matched cohort study. The increased cost of a cementless implant may be negated if one considers the cost savings of not using cement, the cost savings of not performing manipulations, and the shorter operative time.

To Cement or Not? Five-Year Results of a Prospective, Randomized Study Comparing Cemented vs Cementless Total Knee Arthroplasty.

BACKGROUND: The optimal mode of fixation in total knee arthroplasty is a continuing subject of debate. METHODS: Previously, we reported 2-year results for this prospective, randomized trial. Knee Society Scores, Oxford scores, and pain visual analog scales were collected pre-operatively and post-operatively. Minimum 5-year follow-up has been obtained with radiographic analysis for 85 patients. RESULTS: Mean Knee Society Scores and Oxford scores and patient-reported outcomes were similar in both groups. Each group had 1 additional revision, but neither was related to implant fixation. Survivorship with revision as an endpoint was equivalent (95.9% and 95.3%, P = .98). There was no significant difference in radiolucencies observed between groups (P = .10), all were non-progressive. CONCLUSION: Cementless and cemented total knee arthroplasty had equivalent patient-reported outcomes and survivorship at midterm follow-up. Updates are planned at 10 and 15-year intervals to observe long-term modes of failure between these 2 methods of fixation.

Cemented vs Cementless Total Knee Arthroplasty in Morbidly Obese Patients.

BACKGROUND: Primary total knee arthroplasty (TKA) in morbidly obese patients has been associated with greater postoperative complications. Cementless TKA has the potential for biologic fixation which may provide more durable long-term stability. METHODS: This was a multicenter review of 298 TKAs in 292 morbidly obese patients (body mass index, >40) undergoing TKA, with 154 TKAs (149 patients) in the cemented and 144 TKAs (143 patients) in the cementless group. RESULTS: There were significantly more revisions in the cemented group (n = 20) than in the cementless group (n = 1; 13.0% vs 0.7%). There was a significantly higher incidence of aseptic loosening in the cemented cohort vs the cementless cohort (9 vs 0 TKAs). All revisions in the cementless cohort were due to infection (0.7%). CONCLUSION: Cementless fixation may be an alternative in the morbidly obese patient undergoing primary TKA.