Characterizing osteophyte formation in knee osteoarthritis: application of machine learning quantification of a computerized tomography cohort: Implications for treatment.

BACKGROUND: Osteophytes are commonly used to diagnose and guide knee osteoarthritis (OA) treatment, but their causes are unclear. Although they are not typically the focus of knee arthroplasty surgeons, they can predict case difficulty and length. Furthermore, their extent and location may yield much information about the knee joint status. The aims of this computed tomography (CT)-based study in patients awaiting total or partial knee arthroplasty were to: (1) measure osteophyte volume in anatomical sub-regions and relative change as total volume increases; (2) determine whether medial and/or lateral OA affects osteophyte distribution; and (3) explore relationships between osteophytes and OA severity. METHODS: Data were obtained from 4,928 CT scans. Machine-learning-based imaging analyses enabled osteophyte segmentation and quantification, divided into anatomical regions. Mean three-dimensional joint space narrowing (3D-JSN) was assessed in medial and lateral compartments. A Bayesian model assessed the uniformity of osteophyte distribution. We correlated femoral osteophyte volumes with B-scores, a validated OA status measure. RESULTS: Total tibial (25%) and femoral osteophyte volumes (75%) within each knee correlated strongly (R2 = 0.85). Medial osteophytes (65.3%) were larger than lateral osteophytes (34.6%), with similar proportions in both the femur and tibia. Osteophyte growth was found in all compartments, and as total osteophyte volume increased, the relative distribution of osteophytes between compartments did not markedly change. No evidence of variation was found in the regional distribution of osteophyte volume between knees with medial, lateral, both, or no 3D-JSN in the femur or tibia. There was a direct relationship between osteophyte volume and OA severity. CONCLUSIONS: Osteophyte volume increased in both medial and lateral compartments proportionally with total osteophyte volume, regardless of OA location. The peripheral position of femoral osteophytes does not appear to contribute to load-bearing. This suggests that osteophytic growth represents a 'whole-knee'/global response. This work may have broad applications for knee osteoarthritis, both surgically and non-operatively.

The Perspectives of Robotic Surgeons.

Given recent advancements in artificial intelligence and robotic surgery, attention has now been paid to the concept of autonomous surgery. As robotic surgery has developed and matured, examples of autonomous surgery have arisen through the assistance of artificial intelligence. As with any new technology, ethical and legal considerations also arise, and there are special considerations that should be taken into account with the adaptation of new technology involving patient care. In this paper, we will describe autonomous surgery used in general surgery and lower extremity joint arthroplasty, and we will highlight the current ethical and legal considerations associated with this technology.

The Learning Curve From Converting From Fluoroscopic to Robotic-Assisted Direct Anterior Total Hip Arthroplasty.

INTRODUCTION: Robotic-assisted total hip arthroplasty (RA-THA) provides an alternative to fluoroscopic guidance, thus reducing radiation exposure for orthopaedic surgeons. This study was performed to assess the learning curve associated with the adoption of RA-THA using the direct anterior approach (DAA) with regard to surgical time, use of fluoroscopy, and implant placement. In addition, we compared complication rates and patient-reported outcome scores between both cohorts. A case report of an RA-THA is also presented. MATERIALS AND METHODS: This was a retrospective, non-randomized evaluation of the learning curve by assessing surgical time on a consecutive series of 89 DAA cases performed by a single surgeon. There were 53 cases that had manual THA with fluoroscopy and 36 cases with RA-THA. All cases had an acetabular component placement target of 40° inclination and 20° anteversion. An independent reviewer blinded to surgical technique used the Widmer method to measure acetabular inclination and version. Patient demographics were similar for both groups. RESULTS: The mean surgical time for the manual fluoroscopic group was 88 ± 21 minutes and 101 ± 14 minutes for the RA-THA group. After 15 RA-THA cases, surgical time reached time neutral compared to the manual fluoroscopic group. The first 17 RA-THA cases utilized fluoroscopy to verify implant position until the surgeon became comfortable with the accuracy of the RA-THA system. After case 17, fluoroscopy was abandoned in all subsequent RA-THA cases. The mean radiation dose delivered to the surgical field was 5.61 ± 5.71 mGy. Manual THA with fluoroscopy resulted in a mean acetabular inclination of 41.3 ± 4.4° and a mean anteversion of 22.4 ± 3.0°. The RA-THA resulted in a mean acetabular inclination of 42.0 ± 4.2° and a mean anteversion of 22.3 ± 3.9°. There was no noted change in RA-THA placement accuracy after case 17, when fluoroscopy was eliminated from the surgical workflow. There were no statistical differences between the manual fluoroscopic and robotic-assisted groups with respect to complications and clinical PROM outcomes. CONCLUSION: The DAA THA can be performed with RA-THA and achieve comparable acetabular placement without fluoroscopy. Surgical time was higher for the RA-THA group during the learning curve, but then decreased and was consistent with the manual fluoroscopic group after 15 cases.

How-To Create an Orthopaedic Systematic Review: A Step-by-Step Guide Part II: Study Execution.

Systematic reviews are the apex of the evidence-based pyramid, representing the strongest form of evidence synthesizing results from multiple primary studies. In particular, a quantitative systematic review, or meta-analysis, pools results from multiple studies to help answer a respective research question. The aim of this review is to serve as a guide on how to: 1) design; 2) execute, and 3) publish an orthopaedic arthroplasty systematic review. In Part II, we focus on methods to assess data quality through the Cochrane Risk of Bias, Methodological Index for Non-Randomized Studies (MINORS) criteria, or Newcastle-Ottawa scale; enumerate various methods for appropriate data interpretation and analysis; and summarize how to convert respective findings to a publishable manuscript (providing a previously published example). Use of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines is recommended and standard in all scientific literature, including that of orthopaedic surgery. Pooled analyses with forest plots and associated odds ratios and 95% confidence intervals are common ways to present data. When converting to a manuscript, it is important to consider and discuss the inherent limitations of systematic reviews, including their inclusion and/or exclusion criteria and overall quality, which can be limited based on the quality of individual studies (e.g., publication bias, heterogeneity, search/selection bias). We hope our papers will serve as starting points for those interested in performing an orthopaedic arthroplasty systematic review.

Appropriateness of Frequently Asked Patient Questions Following Total Hip Arthroplasty From ChatGPT Compared to Arthroplasty-Trained Nurses.

BACKGROUND: The use of ChatGPT (Generative Pretrained Transformer), which is a natural language artificial intelligence model, has gained unparalleled attention with the accumulation of over 100 million users within months of launching. As such, we aimed to compare the following: 1) orthopaedic surgeons' evaluation of the appropriateness of the answers to the most frequently asked patient questions after total hip arthroplasty; and 2) patients' evaluation of ChatGPT and arthroplasty-trained nurses responses to answer their postoperative questions. METHODS: We prospectively created 60 questions to address the most commonly asked patient questions following total hip arthroplasty. We obtained answers from arthroplasty-trained nurses and from the ChatGPT-3.5 version for each of the questions. Surgeons graded each set of responses based on clinical judgment as 1) "appropriate," 2) "inappropriate" if the response contained inappropriate information, or 3) "unreliable" if the responses provided inconsistent content. Each patient was given a randomly selected question from the 60 aforementioned questions, with responses provided by ChatGPT and arthroplasty-trained nurses, using a Research Electronic Data Capture survey hosted at our local hospital. RESULTS: The 3 fellowship-trained surgeons graded 56 out of 60 (93.3%) responses for the arthroplasty-trained nurses and 57 out of 60 (95.0%) for ChatGPT to be "appropriate." There were 175 out of 252 (69.4%) patients who were more comfortable following the ChatGPT responses and 77 out of 252 (30.6%) who preferred arthroplasty-trained nurses' responses. However, 199 out of 252 patients (79.0%) responded that they were "uncertain" with regard to trusting AI to answer their postoperative questions. CONCLUSIONS: ChatGPT provided appropriate answers from a physician perspective. Patients were also more comfortable with the ChatGPT responses than those from arthroplasty-trained nurses. Inevitably, its successful implementation is dependent on its ability to provide credible information that is consistent with the goals of the physician and patient alike.

Evaluating ChatGPT's Utility in Medicine Guidelines Through Web Search Analysis.

INTRODUCTION: With the rise of machine learning applications in health care, shifts in medical fields that rely on precise prognostic models and pattern detection tools are anticipated in the near future. Chat Generative Pretrained Transformer (ChatGPT) is a recent machine learning innovation known for producing text that mimics human conversation. To gauge ChatGPT's capability in addressing patient inquiries, the authors set out to juxtapose it with Google Search, America's predominant search engine. Their comparison focused on: 1) the top questions related to clinical practice guidelines from the American Academy of Family Physicians by category and subject; 2) responses to these prevalent questions; and 3) the top questions that elicited a numerical reply. METHODS: Utilizing a freshly installed Google Chrome browser (version 109.0.5414.119), the authors conducted a Google web search (www.google.com) on March 4, 2023, ensuring minimal influence from personalized search algorithms. Search phrases were derived from the clinical guidelines of the American Academy of Family Physicians. The authors prompted ChatGPT with: "Search Google using the term '(refer to search terms)' and document the top four questions linked to the term." The same 25 search terms were employed. The authors cataloged the primary 4 questions and their answers for each term, resulting in 100 questions and answers. RESULTS: Of the 100 questions, 42% (42 questions) were consistent across all search terms. ChatGPT predominantly sourced from academic (38% vs 15%, p = 0.0002) and government (50% vs 39%, p = 0.12) domains, whereas Google web searches leaned toward commercial sources (32% vs 11%, p = 0.0002). Thirty-nine percent (39 questions) of the questions yielded divergent answers between the 2 platforms. Notably, 16 of the 39 distinct answers from ChatGPT lacked a numerical reply, instead advising a consultation with a medical professional for health guidance. CONCLUSION: Google Search and ChatGPT present varied questions and answers for both broad and specific queries. Both patients and doctors should exercise prudence when considering ChatGPT as a digital health adviser. It's essential for medical professionals to assist patients in accurately communicating their online discoveries and ensuing inquiries for a comprehensive discussion.

A Comparison Between Polyethylene Exchange and Full Revision for Arthrofibrosis Following Total Knee Arthroplasty.

BACKGROUND: Arthrofibrosis is a debilitating postoperative complication and a major cause of patient dissatisfaction following total knee arthroplasty (TKA). There is no consensus regarding the optimal treatment for stiffness after TKA. For cases not amenable to manipulation under anesthesia (MUA), one component or full revision are both suitable options. In a value-based healthcare era, maximizing cost-effectiveness with optimized clinical outcomes for patients remains the ultimate goal. As such, we compared (1) Knee Injury and Osteoarthritis Outcome Scores for Joint Replacement (KOOS, JR), (2) range of motion (ROM), as well as (3) complication rates, including MUA and lysis of adhesions (LOA), between polyethylene exchange and full component revision for TKA arthrofibrosis. METHODS: Patients were queried from an institutional database who underwent revision TKA for arthrofibrosis between January 1, 2015, and April 31, 2021. There were 33 patients who underwent full revision and 16 patients who underwent polyethylene exchange. Demographics and baseline characteristics between the cohorts were analyzed. Postoperative outcomes included MUA, LOA, and re-revision rates as well as KOOS, JR, and extension and flexion ROM at a mean follow-up of 3.8 years. Baseline comorbidities, including age, body mass index, alcohol use, tobacco use, and diabetes, were comparable between the full revision and polyethylene exchange revision cohorts (P > .05). The one and full component revisions had similar preoperative KOOS, JR (43 versus 42, P = .85), and flexion (81 versus 82 degrees, P = .80) versus extension (11 versus 11 degrees, P = .87) ROM. RESULTS: The full component revision had higher KOOS, JR (65 versus 55, P = .04), and flexion (102 versus 92 degrees, P = .02), but similar extension (3 versus 3 degrees, P = .80) ROM at final follow-up compared to the polyethylene exchange revision, respectively. The MUA (18.2 versus 18.8%, P = .96) and LOA (2.0 versus 0.0%, P = .32) rates were similar between full component and polyethylene exchange revisions. There was one re-revision (3.0%) for the cohort of patients who initially underwent full revision. There were four full re-revisions (25.0%) and two polyethylene exchange re-revisions (12.5%) performed in the cohort of patients who initially underwent a polyethylene exchange revision. CONCLUSIONS: The full component revision for stiffness after TKA showed favorable KOOS, JR, ROM, and outcomes in comparison to the polyethylene exchange revision. While the optimal treatment for stiffness after TKA is without consensus, this study supports the use of the full component revision when applied to the institutional population at hand. It is imperative that homogeneity exists in preoperative definitions, preoperative baseline patient demographics, ROM and function levels, outcome measures, and preoperative indications, as well as the inclusion of clinical data that assesses complete exchange, single exchange, and tibial insert exchange.

The Association of Dental Caries or Dental Implant Placement Within One Year of Primary Total Hip Arthroplasty on Medical and Implant Complications.

INTRODUCTION: Total hip arthroplasty (THA) adverse events among patients who have dental diagnoses remain unclear. We sought to determine if dental caries or dental implant placements increased: 1) 90-day medical complications; 2) 90-day readmissions; and 3) 2-year implant-related complications, including periprosthetic joint infections (PJIs) after THA. METHODS: A nationwide database for primary THAs from 2010 to 2021 was queried to compare three patient cohorts. Patients who had a history of dental implants or caries within 12 months prior to THA (n = 1,179) or 12 months after THA (n = 1,218) were case-matched to patients who did not have dental history (n = 6,090) by age and comorbidities. Outcomes included 90-day complications, 90-day readmissions, and 2-year implant-related complications. Logistic regression models computed the odds ratios (OR) of complications and readmissions. P values less than 0.006 were significant. RESULTS: Patients who had dental caries or implant placement 12 months before or after THA experienced 1.6-fold greater odds of 90-day medical complications compared to case-matched patients. Readmissions within 90 days increased for patients who had a dental history before (11.7 versus 8.3%; OR: 1.49, P < 0.0001) and after (14.2 versus 8.3%; OR: 1.84, P < 0.0001) THA compared to case-matched patients. A dental caries diagnosis or dental implant placement within 12 months following THA increased 2-year implant complications compared to case-matched patients (15.2 versus 9.3%; OR: 1.69, P < 0.0001), including PJIs (5.3 versus 2.8%; OR: 1.98, P < 0.0001), dislocations (4.4 versus 2.7%; OR: 1.63, P = 0.002), and THA revisions (3.9 versus 2.5%; OR: 1.61, P = 0.005). CONCLUSION: Dental diagnoses within 12 months of THA are associated with increased medical complications. Dental diagnoses occurring 12 months after THA are associated with greater implant-related complications, including PJIs. Delaying invasive dental procedures for 12 months after THA may be advisable.

Excellent 10-Year survivorship of robotic-arm-assisted unicompartmental knee arthroplasty.

Introduction: Robotic-arm-assisted unicompartmental knee arthroplasty (UKA) is an excellent solution for patients suffering from single-compartment knee arthritis. While outcomes tend to be favorable for UKAs, revision operations, commonly due to component malpositioning and malalignment resulting in accelerated wear, are a major concern. Intraoperative technologies, such as robotic assistance, can help better ensure that implants are positioned based on a patient's specific anatomy and mechanical physiology. However, long-term survivorship and patient-reported satisfaction with robotic-assisted UKAs are limited. Therefore, the purpose of this study was to assess the 10-year outcomes of patients who underwent robotic-arm-assisted unicompartmental knee arthroplasty. Specifically, we evaluated: 1) 10-year survivorships; 2) patient satisfaction scores; and 3) re-operations. Methods: From a single surgeon and single institution, 185 patients who had a mean age of 65 years (range, 39 to 92) and a mean body mass index of 31.6 (range, 22.4 to 39) at a mean of 10 years follow-up were evaluated (range, 9 to 11). For all patients, the same robotic-assistive device was utilized intraoperatively, and all patients underwent standardized physical therapy and received standardized pain control management. Then 10-year survivorships with Kaplan-Meir curves, patient satisfaction evaluations with a 5-point Likert scale, and re-operations were assessed as primary outcomes. Results: Overall implant survivorship was 99%, with only two patients requiring revision surgery. There was one patient who was converted to a total knee arthroplasty, while the other patient underwent polyethylene exchange at 5 weeks for an acute infection with successful implant retention. Overall, 97% of the patients were satisfied with their postoperative outcomes, with 81% of patients reporting being very satisfied. There were two other patients who required arthroscopic intervention: one to remove a cement loose body, the other to remove adhered scar from the fat pad and the anterior cruciate ligament. Conclusion: This study is one of the first to provide longer-term (mean 10-year) survivorship and patient-reported satisfaction outcomes for robotic-assisted UKA patients. These data show strong support for utilizing this surgical technique, as nearly all patients maintained their original prostheses and reported being satisfied after a mean of 10 years. Therefore, based on these results, we recommend the use of robotic assistance when performing UKAs.

A Nationwide Analysis of the Impact of Socioeconomic Status on Complications and Healthcare Utilizations After Total Knee Arthroplasty Using the Area Deprivation Index: Consideration of the Disadvantaged Patient.

INTRODUCTION: Socioeconomic status (SES) has been demonstrated to be an important prognostic risk factor among patients undergoing total joint arthroplasty. We evaluated patients living near neighborhoods with higher socioeconomic risk undergoing total knee arthroplasty (TKA) and if they were associated with differences in: 1) medical complications; 2) emergency department (ED) utilizations; 3) readmissions; and 4) costs of care. METHODS: A query of a national database from 2010 to 2020 was performed for primary TKAs. The Area Deprivation Index (ADI) is a weighted index comprised of 17 census-based markers of material deprivation and poverty. Higher numbers indicate a greater disadvantage. Patients undergoing TKA in zip codes associated with high ADI (90%+) were 1:1 propensity-matched to a comparison group by age, sex, and Elixhauser Comorbidity Index (ECI). This yielded 225,038 total patients, evenly matched between cohorts. Outcomes studied included complications, ED utilizations, readmission rates, and 90-day costs. Logistic regression models computed the odds ratios (OR) of ADI on the dependent variables. P-values less than 0.003 were significant. RESULTS: High ADI led to higher rates and odds of any medical complications (11.7 versus 11.0%; OR: 1.05, P = 0.0006), respiratory failures (0.4 versus 0.3%; OR: 1.28, P = 0.001), and acute kidney injuries (1.7 versus 1.5%; OR: 1.15, P < 0.0001). Despite lower readmission rates (2.9 versus 3.5%), high ADI patients had greater 90-day ED visits (4.2 versus 4.0%; OR: 1.07, P = 0.0008). The 90-day expenditures ($15,066 versus $12,459; P < 0.0001) were higher in patients who have a high ADI. CONCLUSION: Socioeconomically disadvantaged patients have increased complications and ED utilizations. Neighborhood disadvantage may inform healthcare policy and improve post-discharge care. The SES metrics, including ADI (which captures community effects), should be used to adequately risk-adjust or risk-stratify patients so that access to care for deprived regions and patients is not lost.

Custom Triflange Acetabular Implants for Complex Hip Revisions: A Case Series.

Revision total hip arthroplasty (THA) presents a formidable challenge when addressing extensive acetabular defects, particularly in severe cases classified under Paprosky types 3A and 3B and American Academy of Orthopaedic Surgeons types 3 and 4. Traditional methods often fall short, prompting the potential use of custom triflange acetabular components or patient-specific acetabular implants (PSAIs). These implants are specifically designed to conform to an individual's anatomy, aiming to enhance defect reconstruction and pelvic stabilization. This case series describes the utilization of advanced 3-dimensional printing and rapid prototyping technologies to construct customized acetabular components, which can be instrumental in enabling precise preoperative planning and surgical execution for these difficult acetabular cases and potentially leading to improved surgical outcomes.

Evaluation of an Initial Robotic-Assisted Direct Anterior Approach Cohort Receiving a New Short Metaphyseal Filling Collared Femoral Implant.

BACKGROUND: Shorter, metaphyseal-filling collared stems have become popular with the direct anterior approach (DAA), based on their ease of broaching and insertion through less invasive surgical exposures. To aid with the DAA, robotic-assisted technology provides three-dimensional computed tomography (CT) preoperative planning and intraoperative guidance to accurately assess stem version. With other femoral stems, this has been shown to provide more accurate implant planning and improved patient outcomes. The purpose of this study was to understand femoral stem placement predictability and patient outcomes for a newly designed metaphyseal-filling collared stem system through a DAA in combination with a robotic-assisted system during a single surgeon's initial cases. MATERIALS AND METHODS: A single high-volume surgeon, experienced with robotic-assisted DAA total hip arthroplasty (THA), adopted the use of a metaphyseal-filling collared stem. Intraoperative data and patient outcomes up to six months postoperative were collected prospectively during the surgeon's first 123 cases. Student's t-tests (α=0.05) were used for statistical comparisons. Intraoperative and radiographic assessments were performed for all 123 cases. RESULTS: The estimated version with neck-cut view of the robotic-assisted system was 13.81 ± 3.81°. The final version measurement captured with the robotic-assisted system was 16.56 ± 6.61°. The difference between the estimated version and robotic-assisted measured version was, on average, 2.68 ± 5.7° (p<0.001). The femoral stem sat at the level of the calcar in all but five cases. There were no intraoperative or postoperative periprosthetic fractures. Patients reported significant improvements in reduced Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement (HOOS-JR), Patient-Reported Outcomes Measurement Information System (PROMIS 10), and Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores throughout their six-month recovery process with no patients reporting a periprosthetic joint infection, fracture, or dislocation. CONCLUSION: The use of a metaphyseal-filling collared stem with robotic-assisted DAA resulted in adequate stem version when assessed visually and with CT scan assessments. Version estimation values were improved upon over visual assessments when using the robotic system that maps out the proximal femur and the improvement was also demonstrated when compared to the prior literature. This may also be related to the stem's collar providing a visual guide during stem placement posterior fill of this triple-tapered stem design. Although further follow up is needed to assess longer-term outcomes, at six months postoperatively, patients had significant improvements in patient-reported outcomes with all patients reporting minimal to no restrictions with their THA.

Innovative Hip Distraction Approaches for Total Hip Arthroplasty in Crowe IV Developmental Dysplasia or Similar High-Riding Patients.

BACKGROUND: Total hip arthroplasty (THA) for dislocated hips (Crowe IV dysplasia) presents unique challenges. Conventional approaches involve subtrochanteric osteotomies, but are complex with additional fixation and potentially lead to limb length discrepancies, nerve palsies, and other complications. An alternative strategy is a staged approach, where the femoral head (or remnant) is gradually lowered (distraction technique) to align with the true acetabulum over a period of time, followed by a second-stage anatomically acetabular-positioned THA. External fixation distraction and telescoping internal lengthening devices have been utilized to achieve preoperative alignment. We evaluated these techniques, including the types, time, and amount of distraction needed, as well as outcomes and complication rates. METHODS: In this retrospective case series, 14 patients (9 women, 5 men), who had a mean age of 32 years (range, 16 to 67), underwent staged surgical interventions using hip distraction using external fixators or internal lengthening devices for hip dysplasia and other pathologies (Perthes disease, osteonecrosis) in preparation for a second-stage anatomically placed THA. The mean follow-up duration for external-fixation patients was 10 years (range, 6.5 to 13.4). RESULTS: Staged treatment involved external fixators (n = 8) or internal lengthening devices (n = 6) with a device placement mean of 48 days (range, 42 to 71). The amount of distraction ranged from 6 to 12 cm. There were 2 patients who required uncomplicated revision of the internal lengthening devices, and another patient had a temporary peroneal nerve palsy. There was 1 patient who underwent an acetabular revision at 7 years. CONCLUSIONS: We focused on a challenging patient cohort that emphasizes the efficacy of staged interventions in managing Crowe Type IV dysplasia and similar cases. Favorable outcomes were found with the immediate transition to THA after device removal that effectively addressed soft-tissue contractures and femoral migration. Despite the need for further validation via larger, prospective studies, this innovative approach may pave the way toward optimizing this strategy for these difficult hip pathologies.

Short-term Comparison of Survivorship and Functional Outcomes for Metaphyseal Cones with Short and Long Stems in Revision Total Knee Arthroplasty.

Printed porous titanium metaphyseal cones have become a mainstay for managing bone loss in revision total knee arthroplasty (rTKA). A short or long stem is routinely used when implanting a cone to augment fixation and offload stresses. This retrospective analysis compared the short-term survivorships and functional outcomes for use of a short or long stem with a metaphyseal cone.A total of 179 cases using metaphyseal cones and stems with median follow-up of 1.95 years (interquartile range, 1.00-2.14) were compared based on stem type. There were 55 cases with long stem(s) and 124 cases with short stem(s). Cases with both long and short stems were excluded. Demographics, Kaplan-Meier survivorships, and preoperative and 1-year postoperative patient-reported outcome measures (PROMs; 2011 Knee Society Score [KSS] objective knee score, function, and satisfaction scores; EuroQol five-dimension scale; and Short Form Survey Physical Component Summary and Mental Component Summary scores) were compared using t-tests with a significance level of α = 0.05. There were no significant differences in body mass index (mean ± standard deviation) or sex (men [%]) between the short and long stem cohorts (32.3 ± 5.3, 36.3% and 31.5 ± 5.5, 38.2%, respectively; p > 0.05). Patients who had short stems were younger (65.9 ± 8.8 vs. 69.0 ± 9.4, p = 0.0323).Revision-free survivorship for the femoral or tibial component was 100% for long stems and 98.2% for short stems at 1 and 2 years, respectively (log-rank p = 0.6330). The two revisions in the short group were for infection, thus the survivorship for aseptic loosening was 100% at 2 years for both cohorts. There were no significant differences in preoperative or postoperative PROMs.This study demonstrated that highly porous printed metaphyseal cones provided rTKA with excellent early survivorship and similar PROMs whether a short or long stem was used. Additional studies will be needed to discern longer term differences.