Cementless Posteriorly Stabilized Total Knee Arthroplasty: Seven-Year Minimum Follow-Up Report.

BACKGROUND: The purpose of this study is to evaluate (1) implant survivorship; (2) patient outcomes; (3) complications; and to (4) perform a radiographic analysis of cementless posteriorly stabilized total knee arthroplasty (TKA) patients at a minimum of 7-year follow-up. METHODS: Our original cohort was composed of 114 consecutive cementless posteriorly stabilized total knee arthroplasties (110 patients) performed by a single surgeon between 2008 and 2010. Since our original report, 4 (1 bilateral) patients died and 2 were lost to follow-up. Therefore, there were 104 patients who had 107 knees available for final follow-up. The final cohort included 43 men and 61 women, who had a mean age of 69 years (range 47-87) and were followed from 7 to 9 years (mean 8 years). Patient outcomes and complications were obtained from electronic medical records. Radiographic assessment was done using the Knee Society Radiographic Evaluation System. RESULTS: The all-cause survivorship was 98% (95% confidence interval 1.01-0.96). Since the original report, there has been 1 post-traumatic loosening of the tibial baseplate, and 1 revision for instability. There were no femoral revisions or patella revisions. The mean Knee Society pain score was 93 points (range 80-100) and the function score was 78 points (range 68-95). Excluding revisions, there was no evidence of progressive loosening of any implant components. CONCLUSION: Based on these 7-year minimum follow-ups, femoral, tibial, and patellar cementless hydroxylapatite-coated beaded implants perform well at up to 9 years postoperatively and offer surgeons and patients a cementless option that may provide long-lasting biological fixation.

Evidence-Based Management of Trunnionosis in Metal-on-Polyethylene Total Hip Arthroplasty: A Systematic Review.

Multiple recent reports have indicated a rising awareness of trunnionosis-related implant failures, accounting for up to 3% of all total hip arthroplasty revisions. Moreover, aseptic loosening and osteolysis from local release of metal debris can be the presenting manifestations, and thus the true incidence of trunnionosis is thought to be underreported. Furthermore, the relatively unclear and multifactorial pathogenesis and the widely variable clinical presentations pose a diagnostic challenge. A consensus regarding the ideal intervention and its timing is also lacking. Because of the relative paucity of reports regarding the diagnosis and management of trunnionosis, we conducted this evidence-based review to evaluate the (1) incidence, (2) pathogenesis, (3) diagnosis, and (4) treatment of trunnionosis in metal-on-polyethylene total hip arthroplasty. We then propose an algorithm for the diagnostic work-up and management of this condition.

Linear Wear Rates of a Highly Cross-Linked Polyethylene Hip Liner.

INTRODUCTION: To help limit wear, newer polyethylene liners, such as the highly cross-linked polyethylene (HXLPE) liners, have been developed. These newer liners undergo an alternating irradiation process, resulting in a stronger, longer-lasting liner. The purpose of this study was to analyze the wear rates of patients who underwent THA and received a newer generation HXLPE acetabular insert. Specifically, we compared: 1) linear vector wear amount and 2) linear vector wear rates in patients as an overall cohort and by gender. We also assessed patient satisfaction outcomes comparing preoperative Harris Hip Scores (HHS) to seven-week, one-year, and three-year HHS scores. MATERIALS AND METHODS: A total of 23 patients who underwent total hip arthroplasty (THA) with direct superior approach by a fellowship-trained orthopaedic surgeon at a private practice institution were analyzed after receiving institutional review board approval. Patients had a minimum two-year follow up, with the mean follow up being four years (range, three to five years). All patients received a 36-mm ceramic femoral head with an HXLPE liner. 2D radiographic polyethylene wear analysis was performed using the Martell Hip Analysis Suite (HAS; University of Chicago, Illinois), which has been previously validated in the literature. Outcomes were assessed using Harris Hip Scores. RESULTS: A five-year linear wear rate of 0.073 mm/year (range, 0 to 0.160 mm/year) and an overall mean linear wear rate of 0.096 mm/year (range, 0 to 0.277 mm/year) were found. No significant differences in wear were seen between genders. Additionally, patients reported significantly better results at seven-weeks (83 points [range, 59 to 100 points]) and one-year (94 points [range, 85 to 100 points]) than preoperative (52 points [range, 34 to 73 points]) HSS scores (p<0.05). No patients underwent revision THA. CONCLUSION: The results from this study highlight the benefits of using an HXLPE polyethylene liner in THA patients and further validates previously reported wear rates of HXLPE liners. After an early "wear in" period during the first year, the wear rates steadily decreased over time. This liner showed excellent early outcomes as no patients underwent revision THA. Furthermore, even as early as seven postoperative weeks, patients reported significantly better HHS scores. Future studies should track the same patient cohort over time to help develop a wear-rate prediction model.

Midterm Outcomes of Revision Total Hip Arthroplasty With the Use of a Multihole Highly-Porous Titanium Shell.

BACKGROUND: We are reporting on the minimum 5-year outcomes of patients who underwent revision total hip arthroplasty (THA) using a specific highly-porous titanium shell. We assessed (1) aseptic and all-cause survivorship; (2) functional outcomes; (3) complications; and (4) radiographic outcomes. METHODS: Two hospital databases were evaluated for patients who underwent revision THA due to component instability or aseptic loosening using a cementless highly-porous titanium shell between September 2006 and December 2011. This yielded 35 patients who had a mean age of 61 years (range 14-88 years). Patients had a mean follow-up of 6 years (minimum 5 years). All-cause and aseptic survivorship of the shell was calculated. Functional outcomes were assessed using the Harris Hip Score. We determined the incidence of postoperative complications and performed radiographic evaluation of pelvic radiographs from regular office visits. RESULT: The aseptic survivorship of the acetabular component was 97% (95% confidence interval; 8.1-9.5). The all-cause survivorship of the acetabular component was 91% (95% confidence interval; 7.3-8.1). One patient had an aseptic failure and 2 patients had septic failures. The mean postoperative Harris Hip Score was 76 points (range, 61-91 points). Excluding the aseptic and septic failures, there was no osteolysis or progressive radiolucencies present on radiographic evaluation at final follow-up. CONCLUSION: At a minimum of 5-year follow-up, the highly-porous titanium acetabular revision shell has excellent survivorship and functional outcomes. Although long-term follow-up is needed to further monitor these implants, the results are promising and demonstrate that this prosthesis may be an excellent option for patients undergoing revision THA.

The Learning Curve Associated with the Administration of Intra-Articular Liposomal Bupivacaine for Total Knee Arthroplasty: A Pilot Study.

INTRODUCTION: Liposomal bupivacaine is a long-acting, local, injectable anesthetic that is used to potentially mitigate post-operative pain after total knee arthroplasty (TKA). In addition, it may reduce opioid use in the post-operative period and shorten lengths-of-stay (LOS). There have been mixed results in the literature with regards to its efficacy, which raises questions regarding the injection technique used. Therefore, we evaluated the learning curve associated with injection techniques prior to, and after, formal teaching. Specifically, we compared differences in: 1) opioid use; 2) LOS; 3) pain intensity; and 4) discharge disposition in patients who did not receive liposomal bupivacaine (no infiltration cohort), received liposomal bupivacaine with less optimal technique (subpar infiltration), and received liposomal bupivacaine with appropriate technique (optimal infiltration) during their primary TKA. MATERIALS AND METHODS: A 1:1:1 ratio of 54 consecutive cases of patients who had no liposomal bupivacaine infiltration, those who had subpar infiltration, and those who had optimal infiltration were included. To evaluate opioid use, the dosages were obtained and converted to their respective morphine milliequivalents (mEq). The total mEq usage was obtained for the day of surgery through post-operative day (POD) 3. LOS was recorded in days. Pain scores were calculated using the visual analogue scale (VAS), obtained from the first post-operative physical therapy note. Discharge status was recorded as discharged to home or rehabilitation. We used an ANOVA test for continuous and X2-square test for categorical variables. RESULTS: When compared to patients who had no infiltration, patients who had subpar infiltration had significantly lower opioid use on day 0, while patients who had optimal infiltration had lower opioid use on post-operative day (POD) 0 and 3. When comparing techniques, opioid use was lower on day 3 for patients who had optimal, as compared to subpar technique. However, LOS and VAS were not significantly different among the three groups. The rehab discharge rate was lower for patients who had optimal as compared to subpar technique. CONCLUSION: There is a learning curve associated with liposomal bupivacaine use, and incorporating an appropriate technique can markedly affect post-operative outcomes. This should be taken into account when evaluating the potential benefits of this peri-articular injection. It appears that liposomal bupivacaine may decrease opioid use and pain scores when optimal infiltration techniques are used.

Survivorship and Functional Outcomes of Cementless versus Cemented Total Knee Arthroplasty: A Meta-Analysis.

The purpose of this meta-analysis was to assess the evidence supporting the use of cementless versus cemented total knee arthroplasties (TKAs). Specifically, we evaluated (1) all-cause survivorship, (2) aseptic survivorship, and (3) functional outcomes (Knee Society Scores [KSS], Oxford Knee Scores, Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC] scores, and ranges of motion [ROMs]). A literature search was performed for studies that evaluated cementless versus cemented TKAs published between 2000 and 2017. Selected studies included three randomized controlled trials, three retrospective observational studies, and one prospective observational study that met the following criteria: (1) primary TKAs, (2) compared cementless and cemented TKAs, (3) implant survivorship that described the causes of failure, and (4) at least one functional outcome. To compare the two cohorts, pooled odds ratios (OR) and 95% confidence intervals (95% CI) were used to calculate tibial and femoral implant survivorship, and pooled mean differences (MD) and 95% CI calculated the functional scores and ROMs. Based on pooled data from the few number of studies, cementless TKAs had a better all-cause survivorship (OR = 0.37; 95% CI, 0.15-0.92) and tended to have a better aseptic survivorship (OR = 0.44; 95% CI, 0.17-1.14). However, this is likely due to the 83.3% weight of the single cementless study potentially influencing the analysis. There were no differences in terms of KSS knee (MD = 1.03; 95% CI, -1.13-3.20) or function scores (MD = 5.36; 95% CI, -3.75-14.51), Oxford knee scores (MD = 0.36; 95% CI, -3.84-4.56), or WOMAC scores (MD = 0.62; 95% CI, -0.87-2.11). Moreover, there was no difference in ROMs (MD = 1.47; 95% CI, -0.11-3.05). Cementless TKA had a better all-cause survivorship when compared with cemented fixation, and similar functional outcomes were demonstrated. However, these findings are based on only a few number of studies (n = 7). Therefore, additional prospective, randomized control trials need to be performed to best compare cementless versus cemented outcomes.

Cementless Total Knee Arthroplasty: A Comprehensive Review of the Literature.

This review evaluated (1) original and newer cementless implants; (2) outcomes of newer designs; (3) risks and benefits; and (4) newer cementless vs cemented total knee arthroplasties. A search for all reports on cementless total knee arthroplasties published from January 2010 to April 2017 was performed, and 31 studies were included for final analysis. Newer cementless total knee arthroplasty designs have shown excellent survivorship, functional outcomes, and satisfaction rates in both young and elderly populations. Compared with cement fixation, there may be potential benefits with the newer cementless implants. However, these findings need to be further substantiated with additional studies reporting longer-term results. [Orthopedics. 2018; 41(5):263-273.].

Outcomes of Cementless Total Knee Arthroplasty in Patients With Rheumatoid Arthritis.

The objective of this study was to evaluate implant survivorship, clinical outcomes, postoperative complications, and radiographic outcomes of cementless total knee arthroplasty (TKA) in patients who have rheumatoid arthritis (RA). Patients who underwent a primary cementless posterior-stabilized TKA and who had RA were reviewed. A total of 126 TKAs in 122 patients who had a mean follow-up of 4 years were analyzed. Implant survivorship was calculated. Postoperative clinical and radiographic follow-up was performed at approximately 6 weeks and 3 months and then annually. Changes in range of motion and Knee Society scores were noted. Radiographic evaluation was conducted as part of the follow-up process. Implant survivorship was 99.2%, with 1 aseptic failure. At final follow-up, mean extension and flexion were 2° (range, 0°-10°) and 124° (range, 95°-140°), respectively. Mean Knee Society pain and function scores were 92 points (range, 80-100 points) and 84 points (range, 70-90 points), respectively. There were no surgical complications. No progressive radiolucencies, loosening, or subsidence were noted except from the single aseptic failure reported. This study reports excellent survivorship and clinical and radiographic outcomes of cementless TKAs in RA patients. Although the decision regarding whether to use cemented or cementless TKAs in these patients should be based on surgeon experience and patient characteristics, the recent advances in implant fixation of cementless TKAs indicate no salient contraindications for RA patients. [Orthopedics. 2018; 41(2):103-106.].

Cementless Total Knee Arthroplasty in Patients Older Than 75 Years.

Some surgeons have been hesitant to use cementless fixation for total knee arthroplasty (TKA) in elderly patients due to concerns regarding successful bone biological fixation. Therefore, this study evaluated: (1) implant survivorship, (2) functional outcomes, (3) radiographic outcomes, and (4) complications in patients over 75 years of age who underwent cementless total knee arthroplasty. A total of 134 patients (142 TKAs) older than 75 years at a single institution between June 2008 and June 2014 were retrospectively reviewed. Their mean follow-up was 4 years (range: 2-8 years). The cohort consisted of 91 women and 43 men who had a mean age of 80 years (range: 76 to 88 years). The preoperative diagnoses were osteoarthritis (n = 107 patients), rheumatoid arthritis (n = 21 patients), and osteonecrosis (n = 6 patients). Descriptive statistics were used to calculate the means and ranges and a Kaplan-Meier analysis was performed to determine the aseptic and all cause implant survivorship. Radiographic evaluation was performed using the new Knee Society Radiographic Evaluation and Scoring System. Functional outcomes at the final follow-up as well as all medical and surgical complications were recorded for each patient. The aseptic implant survivorship was 99.3% (95% CI: 7.9-8.1), and the all cause implant survivorship was 98.6% (95% CI: 7.9-8.1). There was one aseptic revision and one septic revision. At the latest follow-up the mean Knee Society pain score was 93 points (range, 80-100 points), and the mean Knee Society function score was 84 points (range, 70-90 points). On radiographic evaluation, there were no progressive radiolucencies, subsidence, and loosening of prostheses at the latest follow-up. The use of cementless TKA demonstrated excellent survivorship, mid-term clinical and functional outcomes, as well as no progressive radiolucencies or subsidence in patients older than 75 years. In addition, there was a low rate of surgical and medical complications. Therefore, cementless TKA may be a good option for patients older than 75 years.