Cementless femoral components in bicondylar hybrid knee arthroplasty in patients with rheumatoid arthritis: A 10-year survivorship analysis

The Evolution, Current Indications and Outcomes of Cementless Total Knee Arthroplasty

Total knee arthroplasty (TKA) has been performed by orthopedic surgeons for decades, but the cementless TKA has only recently gained much interest in the world of arthroplasty. Initially, early designs had multiple complications, particularly with aseptic loosening due to osteolysis and micromotion. However, modifications have shown good outcomes and excellent survivorship. Over the last several decades, changes in implant designs as well as implant materials/coatings have helped with bone in growth and stability. Furthermore, surgeons have been performing TKA in younger and more obese patients as these populations have been increasing. Good results from the cementless TKA compared to cemented TKA may be a better option in these more challenging populations, as several studies have shown greater survivorship in patients that are younger and have a greater BMI. Additionally, a cementless TKA may be more cost effective, which remains a concern in today's healthcare environment. Overall, cemented and cementless TKA have great results in modern times and there is still a debate as to which implant is superior.

Clinical Results in Posterior-Stabilized Total Knee Arthroplasty with Cementless Tibial Component in Porous Tantalum: Comparison between Monoblock and Two Pegs vs. Modular and Three Pegs

Nowadays, total knee arthroplasty (TKA) is widely considered to be the gold standard for treatment of end-stage knee osteoarthritis. Although the optimal mode of fixation in TKA continues to be an important area of investigation, cementless fixation offers the possibility to gain biologic fixation, preserve bone stock and mineral density, and potentially improve survivorship. The purpose of this retrospective study was to evaluate the clinical results of a posterior-stabilized total knee arthroplasty with cementless tibial component in porous tantalum, comparing two groups: Group A (30 patients), TKA with a monoblock component and two pegs, and Group B (22 patients), with a modular component and three pegs. Knee Society Score (KSS) and the Knee Injury and Osteoarthritis Outcome Score (KOOS) were submitted to the patients, and radiographs were collected at the last follow-up. The mean follow-up was 26.32 (20–40) months. Significant differences were not detected between the postoperative KSS values in the two groups (p = 0.44). Evaluating KOOS outcomes, we found in Group A that the rating system showed a statistically significant improvement from a preoperative average rating of 51.4 (SD ± 15) to an average of 72.66 (SD ± 19) at final follow-up (p < 0.05). In Group B, the KOOS rating system showed a statistically significant improvement from a preoperative average rating of 48.3 (SD ± 18) to an average of 79.54 (SD ± 17) postoperatively (p < 0.05). Comparing KOOS final outcomes between groups, we found no statistically significant difference at the mean final follow-up (p = 0.20), with the exception of the sport-related section (p < 0.05). Radiological evaluation at the final follow-up did not show any sign of polyethylene wear, radiolucency, septic or aseptic loosening, or change in alignment in either group. The current study demonstrates an excellent survivorship of cementless tibial components in porous tantalum and the possibility of osseous integration, without significant differences between the two groups under investigation.

Outcomes of Total Knee Arthroplasty in Patients With Rheumatoid Arthritis

The purpose of this study was to examine current literature regarding the efficacy of total knee arthroplasty for patients with rheumatoid arthritis. Studies that assessed total knee arthroplasty outcomes in patients with rheumatoid arthritis were identified on MEDLINE from January 2009 to November 2018. All 4 studies that assessed knee pain and 9 of 11 studies that assessed knee function noted significant improvement in average knee score. However, between 10% and 47% of patients had significant knee pain at final follow-up. Total knee arthroplasty provides significant improvement in knee pain and function for patients with rheumatoid arthritis. However, the rates of postoperative pain vary widely. [Orthopedics. 2021;44(5):e626-e632.].

Cementless Fixation for Total Knee Arthroplasty in Various Patient Populations: A Literature Review

The number of total knee arthroplasties (TKAs) performed in the United States has increased considerably in recent years, with a major contribution from younger patients. Maximizing survivorship of these implants has always been a point of emphasis. Early TKA designs with cementless fixation were associated with high rates of complications and implant failures. However, recent advances in cementless designs have shown excellent results. The decision to use cemented or cementless fixation for patients undergoing TKA is typically based on the surgeon's experience and preference. However, several patient characteristics must also be taken into account. The purpose of this review was to describe the clinical outcomes of studies in which a cementless TKA system was utilized for patients who (1) were less than 60 years of age, (2) were greater than 75 years of age, (3) were obese, (4) had rheumatoid arthritis, and (5) had osteonecrosis of the knee. Based on the studies included in this review, it appears that cementless fixation is a viable option for patients who have all of the above demographics.

Have the annual trends of total hip arthroplasty in rheumatoid arthritis patients decreased?

Background

Rheumatoid arthritis (RA) is characterized by chronic systemic and synovial inflammation, resulting in damage to both cartilage and bone. Medical treatment, which has increasingly relied upon disease modifying anti-rheumatic drugs (DMARDs), may fail to slow disease progression and limit joint damage, ultimately warranting surgical intervention. Up to 25% of RA patients will require lower extremity total joint arthroplasty. Though total hip arthroplasty (THA) is known to improve quality of life and functional measures, clarification is still required with respect to the impact of increased DMARD use on annual rates of THA. Thus, the purpose of this study was to evaluate: (I) the annual trends of THAs due to RA in the United States population; (II) the annual trends in the proportion of THAs due to RA in the United States.

Methods

This study utilized the Nationwide Inpatient Sample (NIS) to identify all patients who underwent THA between 2002 and 2013 (n=3,135,904). Then, THA patients who had a diagnosis of RA, which was defined by the International Classification of Disease 9^th revision diagnosis code 714.0, were identified. The incidence of THAs with a diagnosis of RA in the United States was calculated using the United States population as the denominator. Regression models were used to analyze the annual trends of RA in patients who underwent THA.

Results

Review of the database identified 90,487 patients who had a diagnosis of RA and underwent THA from 2002 to 2013. The annual prevalence of RA in those who underwent THA slightly decreased over the specified time period, with 28.7 per 1,000 THAs in 2002 and 28.6 per 1,000 THAs in 2013; however, this change was not statistically significant (R²=0.158, P=0.200).

Conclusions

The annual rates of THA among RA patients did not show any significant change between 2002 and 2013. DMARD use has decreased both disease progression and joint destruction, and DMARDs are now often utilized as primary treatment. The increase in population of the country during the study period may have overestimated THA trends. Moreover, patients may be more likely to opt for surgical management, given the advances in operative techniques as well as peri- and post-operative course.