Closing the flexion gap: Differences in femoral sizes, level of constraint, and joint anatomy between robotic assisted and conventional high volume orthopedic surgeons.

We investigated outcomes of patients treated with either locked plating or retrograde intramedullary nailing (IMN) at a single institution and compared outcomes of retrograde IMN to locked plating for periprosthetic distal femur fractures. We reviewed 241 subjects with distal femur fractures around total knee arthroplasty (TKA) treated with locked plating (197) or retrograde IMN (44). Mean age was 77 years, 78% were female, and mean BMI was 32kg/m2. There were 27% Su I, 41% Su II, and 32% Su III fractures. There were 87% primary TKAs and 13% revision TKAs. Mean follow-up was 3 years. Overall nonunion rate was 10% and 5-year survivorship free of any revision was 81%, with the most common reasons being nonunion (49%), infection (19%), and aseptic TKA loosening (11%). Patients with prior TKA infection (HR 3; p = 0.02), revision TKA (HR 2; p = 0.03), Su III fractures (HR 2.5; p = 0.04) were at increased risk of revision. There was a trend toward higher non-union rate in the locked plating group (11% vs. 2%; p = 0.07). Those with locked plating had higher rates of osteoporosis (70% vs. 52%; p = 0.02), prior revision TKA (16% vs. 2%; p = 0.02), and Su Type III fractures (36% vs.16%, p = 0.047). Five-year survivorship free of any revision for locked plating and retrograde IMN were 80% and 84%, respectively, with no significant difference in revision, reoperation, or non-operative complications. Both locked plating and retrograde IMN are viable fixation options for periprosthetic distal femur fractures after TKA. Those treated with locked plating had higher rates of osteoporosis, prior revision TKA, and more distal fractures, but did not demonstrate a significant increased risk for reoperation or revision. Level III, Retrospective comparative cohort study.

Purpose This study assessed the ability of the novel Shalby Infected Knee Revision Surgery (SIKRS) score to predict the optimal 2nd stage procedure and risk of failure of a two-stage revision total knee arthroplasty (TKA) for periprosthetic joint infection (PJI). Methods This prospective study included patients who had undergone stage 1 revision TKA for PJI. The SIKRS score was designed based on number of previous surgeries, skin condition, co-morbidities, and type of organism involved. A stage 2 revision TKA was advised for a score ≤25 (category A), an alternative procedure (arthrodesis) for a score ≥40 (category C), and a choice between stage 2 revision TKA and alternative procedure after discussion with the patient for a score between 30-35 (category B). The SIKRS score was applied to each patient in the absence of any sign or symptom of active infection for atleast 12 months. Data was analyzed for outcomes and the positive predictive value (PPV) of SIKRS at a minimum follow-up of 12 & 24 months. Results A total of 57 stage 1 revision TKAs who underwent stage 2 revision procedures were analyzed. There were 42 knees in category A, 7 knees in category B, and 8 knees in category C. At a mean follow-up of 24±7.5 months, mean preoperative total KSS of 91.5±38.5 improved significantly (p<0.0001) to 137.2±27.3. At a minimum 12 months follow-up, there were 42 successes and 0 failures for score ≤25 with PPV of 100%; 4 successes and 3 failures for score 30-35 with PPV of 57.1%; 8 successes and 0 failures for score ≥40 with PPV of 100%; and an overall failure rate of 5.3%. At a minimum 24 months follow-up, there were 24 successes and 0 failures for score ≤25 with PPV of 100%; 3 successes and 2 failures for score 30-35 with PPV of 60%; 2 successes and 0 failures for score ≥40 with PPV of 100%, and an overall failure rate of 6.5%. Conclusion The SIKRS score was useful in predicting success or failure of a stage 2 procedure at a minimum follow-up of 24 months. A score of ≤25 indicates that a stage 2 revision TKA can be performed with minimal chances of failure. The SIKRS score is an attempt to objectify decision-making in a rather ambiguous situation and can may help surgeons identify patients where stage 2 revision TKA can be performed.

The purpose of this study was to compare rates of manipulation under anesthesia (MUA) and revision total knee arthroplasty (TKA) in patients undergoing TKA with and without perioperative use of an angiotensin-receptor blocker (ARB). Embase and PubMed/MEDLINE were searched, and peer-reviewed studies with a minimum follow-up period of 90 days comparing rates of MUA and revision surgery in patients undergoing TKA with and without perioperative use of an ARB were included. Studies that were not available in English and/or used animal models or cadavers, as well as case reports, non-full text articles, review articles, letters to the editor, and studies reporting data that was non-comparative or lacked outcome measures were excluded. Included studies were evaluated for quality using the Methodological Index for Non-Randomized Studies criteria. Patient demographics, comorbidities, and outcomes were extracted from the included studies. Six studies consisting of 997,086 control patients and 129,874 patients who received perioperative ARB were included. All included studies were at level III evidence. Patients taking an ARB had higher rates of diabetes (42% vs 28%), hypertension (87% vs 58%), obesity (34% vs 23%), and hypercholesterolemia (63% vs 35%) compared to the control groups. The rate of MUA across control patients ranged from 2.8% to 7.6%, compared to 2.5% to 6% in patients taking an ARB. The rate of revision TKA across control patients ranged from 1.4% to 7.6%, whereas the rate for patients taking an ARB ranged from 1.14% to 1.3%. Perioperative ARB use may decrease rates of MUA and revisions after TKA. This study can guide risk stratification and counseling for patients undergoing TKA. Higher-level studies need to be conducted to determine whether ARBs should be prescribed for the sole purpose of preventing arthrofibrosis.

Conversion Total Knee and Hip Arthroplasty Requires Increased Energy Expenditure Compared to Primary Knee Arthroplasty.

Influence of Stem Dimensions on Radiological and Clinical Results in Revision Knee Arthroplasty With Metaphyseal Sleeves: A Retrospective Analysis.

Choosing the appropriate implants for reconstruction in revision TKA is essential for long-term fixation. While cones and augments are routinely utilized to address tibial defects, the effect of augment location and size on the biomechanical stability of revision TKA constructs and the indications for the use of metaphyseal cones are not known. Is the risk of cement-implant debonding of revision TKA constructs impacted by the thickness and location (medial versus bicompartmental) of tibial augments and the presence of metaphyseal cones during (1) a demanding daily activity like stair ascent and (2) torsional loads? Under institutional review board approval, we developed patient-specific finite-element models of revision TKA from four patients (three males and one female, ages 50 to 80 years, BMI 27 to 37 kg/m 2 ) who underwent two-stage revision and had a CT scan with no metal artifact after first-stage implant removal. For each patient, we created 5-mm, 10-mm, and 15-mm-thick medial and bicompartmental uncontained defects. We considered two situations for the metaphysis: using a metaphyseal cementless cone into which the implant was cemented or using only cement to fill the metaphyseal cavity. To answer our first question, we conducted finite-element simulations of the immediate postoperative loading scenario representative of stair ascent, while to answer our second research question, we considered an idealized torsional test consisting of 100 N of axial load and twice the axial moment experienced at the same instant of stair ascent. We calculated the risk of cement-implant debonding from an interfacial failure function (calculated as a function of the normal and shear stresses at the cement-implant interface) wherein values of interfacial failure ≥ 1 indicate debonding. Our primary outcome was the cement-implant interface area with ≥ 10% risk of debonding, which we considered to be the interface area with greater than minimal risk of debonding. During stair ascent, we computed a decrease of the cement-implant interface area with greater than minimal risk of debonding (that is, ≥ 10% risk of debonding) with medial uncontained defects (median [IQR] 2.6% [1.4% to 3.7%] with 15-mm augment) but not with bicompartmental defects (5.2% [3.7% to 5.3%]) compared with the scenario with no uncontained defect (5.2% [3.9% to 5.9%]). Compared with using a metaphyseal cone, using cement alone in the metaphysis increased the interfacial area with greater than minimal risk of debonding, reaching a median (IQR) of 13.8% (11.4% to 14.3%) with a 15-mm bicompartmental defect. Under the torsional load scenario, the increase in the area with greater than minimal risk of debonding was small for medial defects, from a median (IQR) of 4.3% (2.5% to 5.3%) to 4.9% (3.9% to 6.2%) when using a metaphyseal cone and from 7.0% (4.0% to 9.5%) to 7.2% (6.1% to 9.8%) when only using cement in the metaphysis. However, the area at risk of failure of bicompartmental defects under torsional loads reached 23% when using a metaphyseal cone and 52% when using only cement in the metaphysis. The size of bicompartmental uncontained defects treated with a bicompartmental augment (a full block) negatively affected the overall construct stability in our finite-element model. However, medial defects of the same size did not negatively influence the stability of the construct when addressed with an augment perfectly contacting the bone. In our computational finite-element model, using metaphyseal cones increased the stability of the revision TKA construct. Our finite-element results suggest that medial augments have little impact on the stability of revision TKA constructs, but clinicians may want to combine bicompartmental augments with cones for increased stability of revision TKA constructs.

Serum Interleukin-6 Exhibits Better Diagnostic Performance Than Serum C-Reactive Protein in Acute Periprosthetic Joint Infection.

Anterior cruciate ligament reconstruction with lateral extra-articular tenodesis: national utilization patterns and 2-year postoperative outcomes.

Comparing Survivorship of Symmetric Versus Asymmetric Tibial Augments in Aseptic Revision Total Knee Arthroplasty.

Instability is a rising cause of revision total knee arthroplasty (rTKA), creating significant challenges for patients, surgeons and the healthcare system. This systematic review and meta-analysis aimed to evaluate the outcomes of conservative management, isolated polyethylene exchange (PE), and rTKA as treatments for post-TKA instability. The primary outcome was patient-reported outcome measures (PROMs), with secondary outcomes including reoperation rates, revision rates, and implant survival (Aim 1). Additionally, the study examined the effect of instability type on PROMs (Aim 2) and the impact of prosthesis constraint on PROMs (Aim 3). A systematic search of studies published from 2000 to July 2024 was conducted. (1) Studies analysing the outcome of conservative treatment, isolated PE exchange or revision surgery for instability were included, reporting on PROMs, reoperations, revisions, and/or survival free from revision. PROMs included the Knee Society Score, both clinical (KSCS) and functional (KSFS). Revision was defined as the removal and replacing of the femoral and/or tibial component. A meta-analysis was only performed for revision surgery as treatment. (2) Instability was classified into flexion and extension instability. (3) Prosthetic constraints analysed included posterior stabilised (PS), condylar constrained knee (CCK), and rotating hinged knee (RHK). A total of 27 articles, involving 4269 knees, were included in the analysis: two studies on conservative management, 12 on isolated PE exchange, and 19 on revision surgeries. (1) Conservative treatment, primary physiotherapy, yielded inconsistent results. Isolated PE exchange showed poor outcomes, with recurrent instability and subsequent revision occurring in 6.5%-18.5% of cases. However, in carefully selected patients, outcomes comparable to rTKA were observed. Revision surgery showed a mean improvement of 32 points (95% confidence interval [CI], 20.5-43.5; p < 0.001) for KSKS and 24.3 points (95% CI, 17.2-31.4; p < 0.001) for KSFS. During follow-up, 5.3% (46/864) of the patients underwent a rerevision, with 41.3% attributed to instability. (2) Extension instability showed a trend toward better KSKS (p = 0.04) and KSFS scores (p = 0.03) than flexion instability, and (3) no evidence of superiority was found between different types of constraint in this study. When guided by appropriate clinical indications, conservative management, isolated PE exchange, and revision surgery can yield favourable outcomes in the treatment of post-TKA instability. Instability remains the leading cause of rerevision, highlighting the need for higher prosthetic constraints when flexion-extension gap balancing cannot be achieved. Level IV, systematic review.

In vitro antibacterial and In vivo osteogenesis of 3D-printed magnesium peroxide–doped calcium phosphate silicate scaffolds for revision total knee arthroplasty

Cementless total knee arthroplasty (TKA) has become a viable option in recent years, and there has been an increase in robotic-assisted technology. Although institutions may monitor their implant usage, the evolution of their use and complication rates have not been well described at a national level in the United States. Therefore, we sought to characterize the use and compare complications between cemented, cementless, manual, and robotic-assisted TKA across the United States.We retrospectively reviewed a commercial claims database and found 94,603 inpatient primary TKAs that were performed with cemented or cementless components between January 1, 2016 and December 31, 2022. Records were reviewed for demographics, use of robotics, complications, and readmissions up to 90 days postoperatively.More cementless TKAs were performed each year, from 4.1% in 2016 to 12.3% in 2022 (odds ratio [OR] = 1.3, p < 0.001). The use of robotic technology increased each year from 7.7% in 2016 to 25.0% in 2022 (OR = 1.3, p < 0.001) and was more commonly used with cementless TKA (OR = 1.3, p < 0.001). Patient factors associated with cementless TKA included younger age (OR = 1.0, p < 0.001) and male sex (OR = 1.3, p < 0.001). Cementless TKA was a risk factor for explantation within 90 days postoperatively (OR = 1.5, p = 0.008), but not aseptic loosening (OR = 0.8, p = 0.6), periprosthetic fracture (OR = 0.2, p = 0.2), infection (OR = 1.3, p = 0.1), revision TKA (OR = 1.4, p = 0.1), manipulation under anesthesia (OR = 1.0, p = 0.9), deep vein thrombosis (OR = 0.9, p = 0.5), pulmonary embolism (OR = 1.2, p = 0.3), or blood transfusion (OR = 0.3, p = 0.1).The use of cementless and robotic TKA is increasing each year, although most inpatient primary TKAs are still performed with manual cemented technique. Although cementless TKA was found to be a risk factor for revision and explanation within 90 days, it was not associated with a specific cause of revision. Further research is needed to better understand why cementless TKA increases these risks.

Establishing the diagnosis of periprosthetic joint infection (PJI) is challenging. To date, no gold standard test exists. Criteria used to diagnose PJI include synovial white blood cell (WBC) count and polymorphonuclear neutrophil (PMN) percentage. Elevations in these markers suggest the presence of PJI. However, it is currently unclear whether PJI is present if levels are discordant with one marker elevated and the other within normal limits. Our objectives were to determine the performance of synovial absolute neutrophil count (ANC) in the diagnosis of chronic PJI and evaluate its accuracy in predicting PJI when discordance exists between WBC and PMN. This retrospective study included 472 patients from a revision arthroplasty registry treated with revision total hip arthroplasty (THA) or revision total knee arthroplasty (TKA). All patients were evaluated with preoperative aspiration and 3 intraoperative cultures. Synovial fluid markers (WBC and PMN) and serum markers (CRP and ESR) were collected. ANC was calculated as the product of WBC count and PMN percentage. Chronic infection was defined using the 2013 version of the Musculoskeletal Infection Society (MSIS) criteria. ANC thresholds were generated using data-driven methods (upper quartile) and the literature-derived estimates. Patients with discordance were identified within the sample population. ANC was compared to other markers in the diagnosis of infection using area under the curve (AUC) analysis on receiver operating characteristic (ROC) curves, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). There were 193 patients with chronic PJI and 279 patients with no infection. Levels of all infection markers including ANC were significantly higher in chronically infected patients compared with noninfected patients. ANC performed well in predicting chronic PJI in patients treated with revision THA and TKA. Discordance between WBC count and PMN percentage occurred in approximately 12% of patients. Based on the results, we propose a diagnostic algorithm for use in patients with discordance (Figure 1B). An ANC threshold of 2983 cells/µL was shown to effectively diagnose chronic PJI in the study population of 472 patients. Further investigation is required to validate the use of ANC in diagnostic algorithms. For any figures or tables, please contact the authors directly.

This study investigated whether patients scheduled for revision total knee arthroplasty (TKA) are systemically exposed to arthroplasty metals, and whether systemic metal levels in these patients differ depending on the implants' levels of constraint. Whole blood samples were collected from patients scheduled for revision TKA (implant group, n = 51) and from arthroplasty-naïve controls (n = 53). Using inductively coupled plasma mass spectrometry, all TKA-relevant metals were quantified. Differences in systemic metal levels in patients with failed unconstrained implants (n = 31) and constrained (n = 20) implants were analysed. Correlations between levels of the different arthroplasty metals were assessed, using the Mann-Whitney test, Kruskal-Wallis test with Dunn's multiple comparison test, Spearman r matrix, and linear regression with Spearman correlation as appropriate. A p < 0.05 was considered statistically significant. Patients scheduled for revision TKA showed significantly higher systemic Co (p < 0.001), Cr (p < 0.001), Mo (p = 0.039), Ti (p < 0.001), Nb (p < 0.001) and Zr (p < 0.001) levels compared with controls. Failed constrained TKA implants were associated with significantly higher levels of Co (p = 0.002), Cr (p = 0.005), Ti (p = 0.047), Nb (p = 0.023) and Zr (p = 0.046) than detected in patients with failed unconstrained TKA implant. In patients awaiting revision of a constrained implant, whole blood levels of Co and Ti (p < 0.001), as well as of Zr and Ti (p < 0.001) significantly correlated, whereas no such correlations were observed in patients with failed unconstrained TKA implant. Patients with failed TKA are systemically exposed to arthroplasty metals. Correlation analyses suggest a link between the release of Co and Ti as well as of Zr and Ti in patients awaiting revision of a constrained TKA implant. Additional research is required to investigate the potential biological effects of TKA-related metals, and to establish clinically relevant systemic threshold levels. Level II, therapeutic study.

Total knee arthroplasty (TKA) is the most effective method of pain relief and increased functional status for end stage knee arthritis. Shared by both surgeons and patients, infection is one of the most feared complications. Due to this fear, patients constantly present to physicians complaining of increased temperature on the operated knee. This common clinical observation can be mistaken as a sign for infection leading to unnecessary investigations or the inappropriate use of antibiotics. We aimed to assess in patients undergoing unilateral, primary total knee arthroplasty, whether the temperature of the operated limb, compared to the non-operative limb, remains elevated up to one year post-operatively using a large prospective, longitudinal observational study design. A prospective longitudinal observational study performed in a single center clinical setting (Alberta Hip and Knee Clinic) with patients undergoing operations at three academic hospitals within Calgary, Alberta. These included the Peter Lougheed Center, Rockyview General Hospital and Foothills Medical Center. Fifteen arthroplasty-trained surgeons participated. Patients were Included if they were having an elective primary total knee arthroplasty. Exclusion criteria included patients who have undergone revision TKA, previous major infection, post-traumatic arthritis with previous hardware, previous major operation on the knee including high tibial osteotomy, open reduction internal fixation or major open ligamentous repair excluding arthroscopic ACL reconstruction. Skin temperatures were taken in 4 quadrants using infrared thermometer on the operated and non-operated knees pre-op, 2 weeks, 6 weeks, 3 months and at one year post-operatively. Subgroup analysis was performed in the patients deemed to have a superficial or deep infection. A total of 1094 patients were enrolled in the research study. 889 patients completed a minimum of 4 out of 5 follow-up appointments. Follow-up was impacted due to the COVID-19 pandemic. 864 patients had a normal post-operative course while 25 were deemed to have either superficial or deep infection. Within primary total knee patients, there was a statistically significant increase in skin temperature in the operated versus non-operated knee at every follow-up including the one year follow-up with p&lt;0.001. However, the effect size was small at one-year follow-up with a mean difference in skin temperature of only 0.3oC. In the infected subgroup, there was also a statistically significant difference in skin temperature at 2, 6 and 12 weeks, with a greater difference in skin temperature between operated and non-operated knees (4.05 degrees versus 3.78 degrees in non-infected). However, there was little clinical difference (0.27 degrees) at two weeks between patients who were infected versus not infected. This study has a direct impact to improve the post-operative interaction between patients and surgeons. It is normal for skin temperature post TKA to increase initially and improve over time but can take up to a year before there is little clinical difference. Because of the small difference in the rise of skin temperature between those infected and not infected, there is little indication that skin temperature is a reliable indicator for infection.

Background/Objectives: The rate of periprosthetic joint infection (PJI) is expected to increase in the next years worldwide, mainly due to increasing volume of total joint replacement, longer prosthesis lifespans, and patients with multiple comorbidities. The aim of this study is to describe our personal technique, the modified Hofmann Articulated Spacer (mHAS), in which a CR femoral shield and a partially threaded cannulated screw are inserted into the liner replicating a tibial stem, and to evaluate the efficacy of the spacer as a definitive treatment option in selected patients with knee infections. Methods: A consecutive series of 132 patients were treated for orthopedic infection at the Orthopedic and Trauma Center, University of Turin, between November 2023 and May 2025. All patients included in the study had undergone knee prosthesis removal followed by the implantation of a modified Hofmann Articulated Spacer (mHAS). Functional recovery was evaluated through clinical examination, particularly knee range of motion, and patient-reported outcome measures (PROMs), including the Knee Society Score (KSS), Oxford Knee Score (OKS), and the EQ-5D-5L Visual Analogue Scale (VAS). Results: Nine patients were enrolled in the study, at a mean follow-up of 8.12 months (range: 3–13). The mean range of motion of the knee was 95 degrees (range: 80–120°, SD: 15°). The Knee Society Score (KSS) presented a mean value of 71.9 (SD: 18.11). The Oxford Knee Score (OKS) showed a mean value of 30.8 (SD: 8.5). The EuroQol-5 Dimension-5 Level Visual Analogue Scale (EQ-5D-5L VAS) scores demonstrated an excellent quality of life among the participants. Conclusions: The Modified Hofmann Articulated Spacer demonstrated good functional, qualitative outcomes and eradication rates in patients who underwent the first-stage revision TKA for PKI. This has led us to propose it as a definitive treatment option for more critical and low-demand patients and to postpone the second-stage surgery in the remaining cohort due to satisfactory spacer joint function without pain.

Abstract Aim Data on physical activity (PA) and sports participation in individuals with total knee arthroplasty (TKA) are limited. This study aimed to assess PA and sports participation before and one year after TKA and to identify associated factors. Subject and methods In this cohort study, patients undergoing primary or revision TKA at a German university hospital (Dec 2019–May 2021) were surveyed one day before and 12 months after surgery. Questionnaires assessed PA, sports participation, sociodemographics, and lifestyle factors; data were linked to medical records. Multivariable logistic regression identified factors associated with sports participation one year postoperatively. Results Of 283 eligible patients, 241 (85%) participated, and 95% provided follow-up data. The 229 patients analysed had a mean age of 69.3 years, with 59% being female. PA was reported by 55% pre- and 53% postoperatively, with a shift of people who were active or not. Sports participation remained stable (65% vs. 67%), with cycling, hiking, swimming, and aquatic exercise most common. Higher education (OR middle vs. low: 2.50; high vs. low: 7.68) and non-smoking status (OR: 4.10) were significantly associated with post-TKA sports participation. Conclusion PA and sports participation remained largely stable across the TKA trajectory, though with a shift in individuals who were and were not physically active. Furthermore, the prevailing hypothesis that predominantly knee-related disease burden is the main driver of activity levels does not appear to be sufficient to explain this finding. Rather, it appears that affected individuals’ educational level and current smoking status have a substantial influence.

Revision total knee arthroplasty (rTKA) is more complex and carries higher risks than primary TKA, especially in patients aged ≥ 80 years. This study examines whether elective rTKA yields similar clinical outcomes and complication rates in octogenarians compared to septuagenarians (70-79 years). From 2010 to 2022, we identified 57 patients aged ≥ 80 years who underwent their first rTKA with at least a two-year follow-up at a single institution. These patients were matched 1:2 based on rTKA indication with 114 patients aged 70-79 years. Data collected included demographics, revision indications, perioperative outcomes, complications, reinterventions, and Knee Society Scores (KSS). These variables were compared between septuagenarians and octogenarians with student-t tests or Mann-Whitney u tests. Aseptic loosening was the most common revision indication in both groups (32.8% of all cases). Septuagenarians received more constrained condylar knee (CCK) implants (51% vs. 23%), while octogenarians received more hinged implants (54% vs. 38%). At 2 years, septuagenarians had higher KSS Function scores (72.7 ± 14.9 vs. 56.8 ± 11.4, p < 0.001). Octogenarians experienced higher complication rates (26.3% vs. 9.6%, p = 0.006) and reinterventions (15.8% vs. 6.2%, p = 0.05). Octogenarians undergoing rTKA exhibited lower functional outcomes and gains, along with higher rates of postoperative complications and reinterventions compared to septuagenarians. Further evaluation using patient frailty indices may improve understanding and help balance the risks and benefits of revision surgery in this population.

Background:A periprosthetic tibial fracture (PPTF) is a known complication of medial unicompartmental knee arthroplasty (mUKA). Treatment options include conversion to total knee arthroplasty (cTKA), open reduction internal fixation (ORIF), and nonoperative treatment. The risk of reoperation after initial treatment of PPTFs is not well examined. Given the rise of cementless mUKA and its association with early (≤4 months), likely surgery-related fractures, this group is particularly interesting. The aim of this study was to (1) report the 2-year risk of reoperation according to initial treatment and (2) report the need for delayed conversion to TKA (dcTKA) after ORIF or nonoperative treatment, or the need for revision TKA (rTKA) after cTKA.Methods:Using data from the Danish Knee Arthroplasty Register and the Danish National Patient Register, all PPTFs after mUKAs between 1997 and 2022 were included and stratified by treatment. Subsequent reoperations and need for dcTKA or rTKA within 2 years were outcomes.Results:We identified 177 PPTFs after mUKA with complete 2-year follow-up. When the treatment of the PPTF was cTKA (69 cases), 5 cases (7%) underwent reoperation and fewer than 5 required rTKA. For nonoperative treatment (46 cases), 13 cases (28%) underwent reoperation, with 10 cases requiring dcTKA. When treated with ORIF (62 cases), 25 cases (40%) underwent reoperation, with 19 cases requiring dcTKA. PPTFs after cemented mUKA were mostly late PPTFs (70%) and were often treated nonoperatively, where PPTFs after cementless mUKA were often early PPTFs (74-78%) and very rarely treated nonoperatively. Fixation of mUKA was not associated with the risk of reoperation within each treatment group. Among 74 early PPTFs after cementless mUKA, 35 cases were treated with cTKA with fewer than 5 reoperations within 2 years and 0 cases needing rTKA. In contrast after ORIF (39 cases), 16 cases (41%) underwent reoperation, with 12 cases requiring dcTKA.Conclusion:PPTFs treated with ORIF were associated with higher rates of reoperation and need for dcTKA compared with PPTFs treated with cTKA and nonoperative treatment. These data suggest that careful consideration is needed before using ORIF as treatment. However, the unknown fracture severity precludes definitive attribution of reoperation to the treatments.Level of Evidence:Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.