Femoral Component Design Is Associated With the Risk of Periprosthetic Femur Fracture After Cementless THA in Patients 65 Years or Older.

BACKGROUND: Periprosthetic femur fracture is a known complication after THA. The associated risk of cementless femoral component design for periprosthetic femur fracture in a registry population of patients older than 65 years has yet to be clearly identified. QUESTIONS/PURPOSES: (1) Is femoral stem geometry associated with the risk of periprosthetic femur fracture after cementless THA? (2) Is the presence or absence of a collar on cementless femoral implant designs associated with the risk of periprosthetic femur fracture after THA? METHODS: We analyzed American Joint Replacement Registry data from 2012 to March 2020. Unique to this registry is the high use of cementless femoral stems in patients 65 years and older. We identified 266,040 primary cementless THAs during the study period in patients with a diagnosis of osteoarthritis and surgeries linked to supplemental Centers for Medicare and Medicaid data where available. Patient demographics, procedure dates, and reoperation for periprosthetic femur fracture with revision or open reduction and internal fixation were recorded. The main analysis was performed comparing the Kheir and Chen classification: 42% (112,231 of 266,040) were single-wedge, 22% (57,758 of 266,040) were double-wedge, and 24% (62,983 of 266,040) were gradual taper/metadiaphyseal-filling cementless femoral components, which yielded a total of 232,972 primary cementless THAs. An additional analysis compared cementless stems with collars (20% [47,376 of 232,972]) with those with collarless designs (80% [185,596 of 232,972]). A Cox proportional hazard regression analysis with the competing risk of death was used to evaluate the association of design and fracture risk while adjusting for potential confounders. RESULTS: After controlling for the potentially confounding variables of age, sex, geographic region, osteoporosis or osteopenia diagnosis, hospital volume, and the competing risk of death, we found that compared with gradual taper/metadiaphyseal-filling stems, single-wedge designs were associated with a greater risk of periprosthetic femur fracture (HR 2.9 [95% confidence interval (CI) 2.2 to 3.9]; p < 0. 001). Compared with gradual taper/metadiaphyseal-filling stems, double-wedge designs showed an increased risk of periprosthetic femur fracture (HR 3.0 [95% CI 2.2 to 4.0]; p < 0. 001). Collarless stems showed an increased risk of periprosthetic fracture compared with collared stems (HR 7.8 [95% CI 4.1 to 15]; p < 0. 001). CONCLUSION: If cementless femoral fixation is used for THA in patients 65 years or older, surgeons should consider using gradual taper/metadiaphyseal-filling and collared stem designs because they are associated with a lower risk of periprosthetic femur fracture. Future investigations should compare gradual taper/metadiaphyseal-filling and collared cementless designs with cemented fixation in this population. LEVEL OF EVIDENCE: Level III, therapeutic study.

What Are the Mortality, Infection, and Nonunion Rates After Periprosthetic Femoral Fractures in the United States?

BACKGROUND: Periprosthetic femoral fractures are a serious complication that put a high burden on patients. However, comprehensive analyses of their incidence, mortality, and complication rates based on large-registry data are scarce. QUESTIONS/PURPOSES: In this large-database study, we asked: (1) What is the incidence of periprosthetic femoral fractures in patients 65 years and older in the United States? (2) What are the rates of mortality, infection, and nonunion, and what factors are associated with these outcomes? METHODS: In this retrospective, comparative, large-database study, periprosthetic femoral fractures occurring between January 1, 2010, and December 31, 2019, were identified from Medicare physician service records encompassing services rendered in medical offices, clinics, hospitals, emergency departments, skilled nursing facilities, and other healthcare institutions from approximately 2.5 million enrollees. These were grouped into proximal, distal, and shaft fractures after TKA and THA. We calculated the incidence of periprosthetic femur fractures by year. Incidence rate ratios (IRR) were calculated by dividing the incidence in 2019 by the incidence in 2010. The Kaplan-Meier method with Fine and Gray subdistribution adaptation was used to calculate the cumulative incidence rates of mortality, infection, and nonunion. Semiparametric Cox regression was applied with 23 measures as covariates to determine factors associated with these outcomes. RESULTS: From 2010 to 2019, the incidence of periprosthetic femoral fractures increased steeply (TKA for distal fractures: IRR 3.3 [95% CI 1 to 9]; p = 0.02; THA for proximal fractures: IRR 2.3 [95% CI 1 to 4]; p = 0.01). One-year mortality rates were 23% (95% CI 18% to 28%) for distal fractures treated with THA, 21% (95% CI 19% to 24%) for proximal fractures treated with THA, 22% (95% CI 19% to 26%) for shaft fractures treated with THA, 21% (95% CI 18% to 25%) for distal fractures treated with TKA , 22% (95% CI 17% to 28%) for proximal fractures treated with TKA, and 24% (95% CI 19% to 29%) for shaft fractures treated with TKA. The 5-year mortality rate was 63% (95% CI 54% to 70%) for distal fractures treated with THA, 57% (95% CI 54% to 62%) for proximal fractures treated with THA, 58% (95% CI 52% to 63%) for shaft fractures treated with THA, 57% (95% CI 52% to 62%) for distal fractures treated with TKA , 57% (95% CI 49% to 65%) for proximal fractures treated with TKA, and 57% (95% CI 49% to 64%) for shaft fractures treated with TKA. Age older than 75 years, male sex, chronic obstructive pulmonary disease (HR 1.48 [95% CI 1.32 to 1.67] after THA and HR 1.45 [95% CI 1.20 to 1.74] after TKA), cerebrovascular disease after THA, chronic kidney disease (HR 1.28 [95% CI 1.12 to 1.46] after THA and HR 1.50 [95% CI 1.24 to 1.82] after TKA), diabetes mellitus, morbid obesity, osteoporosis, and rheumatoid arthritis were clinical risk factors for an increased risk of mortality. Within the first 2 years, fracture-related infections occurred in 5% (95% CI 4% to 7%) of patients who had distal fractures treated with THA, 5% [95% CI 5% to 6%]) of patients who had proximal fractures treated with THA, 6% (95% CI 5% to 7%) of patients who had shaft fractures treated with THA, 6% (95% CI 5% to 7%) of patients who had distal fractures treated with TKA , 7% (95% CI 5% to 9%) of patients who had proximal fractures treated with TKA, and 6% (95% CI 4% to 8%) of patients who had shaft fractures treated with TKA. Nonunion or malunion occurred in 3% (95% CI 2% to 4%) of patients with distal fractures treated with THA, 1% (95% CI 1% to 2%) of patients who had proximal fractures treated with THA, 2% (95% CI 1% to 3%) of patients who had shaft fractures treated with THA, 4% (95% CI 3% to 5%) of those who had distal fractures treated with TKA, , 2% (95% CI 1% to 4%) of those who had proximal fractures treated with TKA, and 3% (95% CI 2% to 4%) of those who had shaft fractures treated with TKA. CONCLUSION: An increasing number of periprosthetic fractures were observed during the investigated period. At 1 and 5 years after periprosthetic femur fracture, there was a substantial death rate in patients with Medicare. Conditions including cerebrovascular illness, chronic kidney disease, diabetes mellitus, morbid obesity, osteoporosis, and rheumatoid arthritis are among the risk factors for increased mortality. After the surgical care of periprosthetic femur fractures, the rates of fracture-related infection and nonunion were high, resulting in a serious risk to affected patients. Patient well-being can be enhanced by an interdisciplinary team in geriatric traumatology and should be improved to lower the risk of postoperative death. Additionally, it is important to ensure that surgical measures to prevent fracture-related infections are followed diligently. Furthermore, there is a need to continue improving implants and surgical techniques to avoid often-fatal complications such as fracture-associated infections and nonunion, which should be addressed in further studies. LEVEL OF EVIDENCE: Level III, therapeutic study.

Reducing the Burden of Disease Associated With Periprosthetic Fractures: Prevention and the Need for Improved Perioperative Care.

The management of periprosthetic fractures remains challenging and controversial. There continues to be a significant burden of disease and substantial resource implications associated with fractures following total joint arthroplasty. Achieving consensus opinions regarding the prevention and treatment of this problem has important implications given the profound effect on patient outcomes. Multidisciplinary care in the preoperative and postoperative settings is critical, with a specific focus on bone health.

Fixation Strategies for Periprosthetic Fractures With Stable Implants.

The fixation of periprosthetic fractures remains challenging and controversial. It is important to achieve consensus opinions regarding the management of stable periprosthetic fractures with internal fixation. Key strategies to optimize surgical decision making and fixation and manage complications following these difficult injuries are addressed.

The Role of Revision Total Joint Arthroplasty for Periprosthetic Fractures With Unstable Implants.

The management of periprosthetic fractures with unstable prosthetic implants is a challenging and commonly encountered problem. It is important to address the many current issues and controversies regarding the treatment of periprosthetic fractures with revision total joint arthroplasty. Key strategies to optimize surgical decision making around the use of arthroplasty and management of complications following these complex injuries will be addressed.

Aseptic Acetabular Revisions ≤90 Days, 91 Days to 2 Years, and >2 Years After Total Hip Arthroplasty: Comparing Etiologies, Complications, and Postoperative Outcomes.

BACKGROUND: Isolated acetabular component revision is an effective treatment for revision total hip arthroplasty patients who have well-fixed femoral implants. We aimed to evaluate the modes of acetabular failure following primary total hip arthroplasty and to identify factors associated with increased morbidities and postoperative outcomes. METHODS: We conducted a retrospective analysis and identified 318 isolated aseptic acetabular revisions. We separated patients by ≤90 days, 91 days to 2 years, and >2 years for acetabular revisions and compared demographics, reasons for revision, 90-day readmissions, rerevisions, and postrevision infections. Revisions ≤90 days, 91 days to 2 years, and >2 years accounted for 10.7, 19.2, and 70.1% of revisions, respectively. Revisions ≤90 days, 91 days to 2 years, and >2 years had their primary total hip arthroplasty at a mean age of 66, 63, and 55 years (P < .001), respectively. RESULTS: Revisions within 90 days were mainly indicated for dislocation/instability (58.8%) or periprosthetic fracture (23.5%) while revisions over 2 years were indicated for polyethylene wear/osteolysis (37.2%). Patients with revisions past 90 days were more likely to require rerevision compared to patients with revisions within 90 days (P < .001). There were no differences in readmissions (P = .28) or infection rates (P = .37). CONCLUSIONS: Acetabular revisions within 90 days were more commonly indicated for instability and periprosthetic fracture, while those over 2 years were indicated for polyethylene wear. Revisions past 90 days were more likely to require subsequent rerevisions without increased 90-day readmissions or infections. LEVEL III EVIDENCE: Retrospective cohort study.

Intraincisional Pin Placement is Safe for Robotic-Assisted Total Knee Arthroplasty.

BACKGROUND: While robotic-arm assisted total knee arthroplasty (RA-TKA) has seen a major increase in its utilization, it requires bone array pins to be fixed into the femur and tibia, which intrinsically carries a risk. As it is currently off-label with some robotic platforms to place pins intraincisional, we aimed to evaluate the safety of intraincisional pin placement during RA-TKAs. METHODS: A prospective cohort of 2,343 patients who underwent RA-TKA at a North American Healthcare System between January 2018 and March 2022 was included. Primary outcomes included periprosthetic fracture or infection (eg, superficial or deep). Secondary outcomes included 1-year reoperation rate due to any cause. Cases were retrospectively reviewed to determine whether complications could be attributed to metaphyseal intraincisional pin placement (4.0 mm pins; two tibial and two femoral). The 90-day follow-up was 100% and the 1-year follow-up rate was 70.6% (n = 1,655). RESULTS: The pin-site related periprosthetic fracture incidence at 90 days was 0.09% (2 out of 2,343). The 90-day infection incidence was 1.4% (superficial: 22; deep: 13). The 1-year reoperation rate was 1.8% (29 out of 1,655). The most common causes of reoperation at 1-year were deep infection (n = 14; 0.83%), superficial infection (n = 3; 0.18%), periprosthetic fracture, mechanical symptoms, instability, and hematoma (n = 2; 0.12% for each). CONCLUSIONS: One in 1,172 patients may experience a pin-related periprosthetic fracture after RA-TKA with intraincisional bone array pin placement. There was a low 90-day infection incidence and reoperations within 1-year after RA-TKA were rare.

Postoperative Angiotensin Receptor Blocker Use is Associated With Decreased Rates of Manipulation Under Anesthesia, Arthroscopic Lysis of Adhesions, and Prosthesis-Related Complications in Patients Undergoing Total Knee Arthroplasty.

BACKGROUND: The cellular mechanisms underlying excess scar tissue formation in arthrofibrosis following total knee arthroplasty (TKA) are well-described. Angiotensin receptor blockers (ARB), particularly losartan, is a commonly prescribed antihypertensive with demonstrated antifibrotic properties. This retrospective study aimed to assess the rates of 1- and 2-year postoperative complications in patients who filled prescriptions for ARBs during the 90 days after TKA. METHODS: Patients undergoing primary TKA were selected from a large national insurance database, and the impact of ARB use after TKA on complications was assessed. Of the 1,299,106 patients who underwent TKA, 82,065 had filled at least a 90-day prescription of losartan, valsartan, or olmesartan immediately following their TKA. The rates of manipulation under anesthesia (MUA), arthroscopic lysis of adhesions (LOA), aseptic loosening, periprosthetic fracture, and revision at 1 and 2 years following TKA were analyzed using multivariable logistic regressions to control for various comorbidities. RESULTS: ARB use was associated with decreased rates of MUA (odds ratio [OR] = 0.94, 95% confidence interval (CI), 0.90 to 0.99), arthroscopy/LOA (OR = 0.86, 95% CI, 0.77 to 0.95), aseptic loosening (OR = 0.71, 95% CI, 0.61 to 0.83), periprosthetic fracture (OR = 0.58, 95% CI, 0.46 to 0.71), and revision (OR = 0.79, 95% CI, 0.74 to 0.85) 2 years after TKA. CONCLUSIONS: ARB use throughout the 90 days after TKA is associated with a decreased risk of MUA, arthroscopy/LOA, aseptic loosening, periprosthetic fracture, and revision, demonstrating the potential protective abilities of ARBs. Prospective studies evaluating the use of ARBs in patients at risk for postoperative stiffness would be beneficial to further elucidate this association.

Increased Rates of Late Periprosthetic Fractures in Larger Hydroxyapatite-Coated Cementless Stems: Are Collared Stems a Better Alternative for Total Hip Arthroplasty?

BACKGROUND: Cementless hip stems are widely used for total hip arthroplasty (THA) and have demonstrated excellent survivorship. This study aimed to investigate the effects of stem size and calcar collars on rates of revision due to periprosthetic fracture. METHODS: All primary THA procedures recorded by the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) from September 1999 to December 2021 for a diagnosis of osteoarthritis using a single cementless hip stem with modern bearings were included. The primary outcome measure was revision due to periprosthetic fracture. Stems were divided into 2 groups for comparison, large (size 14 to 20) and small-medium (6 to 13). A subanalysis was performed for collared stems. A total of 59,518 primary THA procedures were included. RESULTS: The cumulative percent revision for periprosthetic fracture was significantly higher for large stems compared to small-medium stems (hazard ratio [HR] = 1.57 [95% confidence interval {CI} 1.18, 2.09] P = .002). Furthermore, collared stems had significantly lower revision rates due to late periprosthetic fracture compared to collarless variants (2 week + HR = 4.55 [95% CI 3.23, 6.42], P < .001). Large collarless stems were found to have greater revision rates due to fracture compared to small-medium collarless stems (HR = 1.55 [95% CI 1.13, 2.12] P = .006), but no difference was found between collared groups (HR = 1.37 [95% CI 0.68, 2.78] P = .382). CONCLUSION: Large cementless hip stems have a higher rate of revision due to periprosthetic fracture compared to small-medium stems. Using a collared stem reduces the rate of periprosthetic fracture.

Sex-Specific Implant Fixation Can Reduce Revision Rates in Total Hip Arthroplasty: Evidence From the Swiss National Joint Registry.

BACKGROUND: Patient's sex is considered a risk factor for revision following primary total hip arthroplasty (THA), but sex-specific treatment guidelines are lacking. The purpose was to assess sex-specificity of risk factors for periprosthetic femoral fractures (PFFs) and aseptic stem loosening (ASL) in a nationwide register study. METHODS: All uncemented and hybrid THAs for hip osteoarthritis registered in the Swiss National Joint Registry were considered. 86,423 THAs were analyzed. Comparable THA subsets for both sexes were obtained through propensity score matching (1:1). A sex-specific analysis of risk factors for early PFF or ASL was performed using recursive partitioning analyses. RESULTS: In women, PFFs were most significantly associated with uncemented THA fixation (P < .0001) and age (P < .01, threshold: 70.5 years). The ASLs were solely associated with patient age of <65 years (P = .023). In men, PFFs were associated exclusively with an American Society of Anesthesiologists (ASA) score >2 (P = .026). The ASLs were not correlated to any of the potential risk factors analyzed. A mathematical simulation indicated that avoiding uncemented THA fixation in women ≥70.5 years of age decreased the number of revisions within the observational period by 21% in this subset and by 4.9% in the entire patient population. CONCLUSION: Uncemented THA should be avoided in women >70.5 years due to the increased risk of early PFF, while the mode of stem fixation did not influence revision risk in men. A sex-specific regimen for THA fixation has the potential to markedly reduce early THA revision rates.

Experience of an Anatomic Femoral Stem in a United Kingdom Center - Excellent Survivorship and Negligible Periprosthetic Fracture Rates at Mean 12 Years Following Primary Total Hip Arthroplasty.

BACKGROUND: As the clinical burden of periprosthetic fractures (PPFs) continues to increase, it has been suggested that the use of anatomical femoral stems may help reduce PPF risk. The primary aim of this study was to determine the survivorship and PPF rate of an anatomical femoral stem in a single center at minimum 10-year follow-up. METHODS: A total of 1,000 consecutive total hip arthroplasties (THAs) performed using an anatomical femoral stem were identified from a prospectively collected arthroplasty database. Patient radiographs were reviewed finally at a mean of 12 years (range, 10 to 16 years) following surgery to identify any revision surgery, dislocations or PPFs. Mean patient age at surgery was 69 years (range, 24 to 93). There were 634 women (63%). Osteoarthritis was the operative indication in 946 patients (95%). RESULTS: All-cause THA survivorship was 99.1% (95% confidence interval (CI), 99.0-99.3%) at 10 years and 97.9% (CI, 97.8 - 98.0%) at 15 years. Stem survivorship at 10 years was 99.6% (CI, 99.5-99.7%) and at 15 years was 98.2% (CI, 98.1-98.3%). The 15-year stem survival for aseptic loosening was 100% with no cases of significant lysis found (lucent line >2mm). Implant survivorship was not significantly impacted by patient sex (P = .65), body mass index (P = .49), deprivation level (P = .284), operative indication (P = .33), or American Society of Anesthesiologists class (P = .374). There were 3 PPFs identified (0.3%) at mean 12-year follow-up and 15 dislocations (1.5%). CONCLUSION: This anatomical femoral stem demonstrated excellent survivorship and negligible PPF rates at mean 12-year follow-up following primary THA.

Mean 23-Year Outcomes of Total Hip Arthroplasty Using a Modular Femoral Stem With Metaphyseal Fixation Sleeve.

BACKGROUND: Although the modular sleeve concept for femoral implants has several advantages, studies reporting on greater than 20-year outcomes are limited. This study aimed to report the mean 23-year results of total hip arthroplasty (THA) using a modular stem with metaphyseal fixation sleeve. METHODS: This study reviewed primary THAs performed using a modular stem between October 1994 and April 1998. Of the 272 hips (221 patients) identified, 220 hips (177 patients) satisfying the minimum 20-year follow-up were included. The Harris Hip Score was used for clinical evaluation. Final hip radiographs were analyzed to evaluate the implant stability and the extent of femoral osteolysis. The mean follow-up duration was 23 years (range, 20 to 28). RESULTS: The mean Harris Hip Score improved from 38 points (range, 26 to 67) preoperatively to 90 points (range, 71 to 100) at the final follow-up (P < .001). Femoral osteolysis was observed in 146 hips (67.1%), but 145 were located proximal to the osseo-integrated sleeve. Overall, 4 femoral revisions were performed; 2 for chronic infection, one for aseptic loosening, and one for periprosthetic femoral fracture. Of the 19 (8.6%) periprosthetic femoral fractures, the most common type was Vancouver AG (13 hips). One (0.5%) asymptomatic distal stem fracture occurred, while no complications were identified at the stem-sleeve junction. Implant survivorship free of any femoral revision was 98.3% at 23 years. CONCLUSIONS: A THA using a modular stem with metaphyseal fixation sleeve demonstrated 98.3% stem survivorship with excellent clinical outcomes at a mean follow-up of 23 years in non-obese patients.

Incidences and Outcomes of Operatively Treated Interprosthetic Femoral Fractures Compared to Vancouver Type C and Rorabeck Type II Fractures.

BACKGROUND: This case-control study evaluated the incidences and outcomes of interprosthetic femoral fracture (IPFF) (Group I) and performed comparisons with Vancouver type C (Group II) and Rorabeck type II (Group III) periprosthetic femoral fractures (PPFF) occurring at similar anatomic sites. METHODS: A retrospective analysis was performed for all patients who had a previously implanted total hip arthroplasty (THA) and total knee arthroplasty (TKA), who lived in the hospital district and had undergone surgery due to PPFF. A total of 153 PPFFs [Group I (n = 31), Group II (n = 21), and Group III (n = 108)] were included. The annual incidences of PPFFs were summarized per 100,000 individuals. The risks of complications, reoperations, and mortalities were evaluated for all groups. RESULTS: The mean population-based annual incidence was 0.9 per 100,000 person years for Group I, 0.7 per 100,000 person years for Group II, and 3.1 per 100,000 person years for Group III. A total of 25 of 153 (16%) major complications were found and 23 of 153 (13%) cases resulted in a revision surgery. The cumulative incidence of death in Group I was 50.4% at 10 years, in Group II it was 63.8% at 10 years, and in Group III it was 74.9% at 10 years. CONCLUSION: The annual incidence of the IPFF almost doubled while the incidence of Vancouver type C stayed stable and Rorabeck type II incidence increased 5-fold. Most of the major complications occurred in IPFF group, while Rorabeck type II patients had the worst survival.

A Consecutive Series of Vancouver B2 Periprosthetic Femur Fractures Treated With Contemporary Monoblock Versus Modular Revision Stems: Clinical and Radiographic Outcomes.

BACKGROUND: Tapered fluted titanium (TFT) stems are the implant design of choice for managing Vancouver B2 periprosthetic femur fractures (PFFs), producing reliable results over the past few decades. The aim of this study was to compare the radiographic and clinical outcomes of Vancouver B2 PFFs treated with contemporary monoblock versus modular TFTs. METHODS: A consecutive series of 113 patients (72 women, 64%, mean age 70 years [range, 26 to 96]) who had a B2 PFF were treated with either a monoblock (n = 42) or modular (n = 71) TFT stem between 2008 and 2021. The mean body mass index was 30 ± 7. The mean follow-up was 2.9 years. A radiographic review was performed to assess leg length and offset restoration, endosteal cortical contact length, and stem subsidence. Kaplan-Meier analyses were used to determine survivorship without revision, reoperation, or dislocation. RESULTS: There was no difference in the restoration of leg length (0.3 ± 8.0 mm) or offset (2.8 ± 8.2 mm) between the monoblock and modular cohorts (P > .05). Mean endosteal cortical contact length (47.2 ± 26.6 versus 46.7 ± 2 6.4 mm, P = .89) and stem subsidence (2.7 ± 3.5 versus 2.4 ± 3.2 mm, P = .66) did not differ. No difference in patient-reported outcome measures (Hip Disability and Osteoarthritis Outcome Score-Joint Replacement; Veterans RAND 12 Item Health Survey Physical and Mental; visual analog score; and Lower Extremity Activity Scale) between the groups was observed. Survivorship at 2 years free from reoperation, revision, and dislocation was 90.4, 90.3, and 97.6%, respectively, for the monoblock cohort; and 84.0, 86.9, and 90.0%, respectively, for the modular cohort. CONCLUSIONS: No significant differences in radiographic or clinical outcomes were observed between patients treated with monoblock or modular TFTs in this large series of B2 PFFs.

Systematic Review and Meta-Analysis of Studies Comparing the Rate of Post-operative Periprosthetic Fracture Following Hip Arthroplasty With a Polished Taper Slip versus Composite Beam Stem.

BACKGROUND: We compared the incidence of postoperative periprosthetic femoral fractures (POPFF) following hip arthroplasty with either a cemented polished taper slip (PTS) stem or a cemented composite beam (CB) stem in comparative studies. METHODS: A systematic review of comparative studies, written in English and published in peer-reviewed journals since the year 2000, was conducted. Study quality was assessed using the Newcastle-Ottawa scale.The overall study qualities were good. There were 913,021 patients from 18 cohorts included in the meta-analysis. There were 294,540 patients who received a CB stem and 618,481 received a PTS stem. Cohorts were classified as high- or low-risk for POPFF based on patient risk factors. A metanalysis was performed using a random effects model, and the relative incidence with 95% confidence intervals (CIs) was reported. RESULTS: The patients at low risk of POPFF had an incidence rate ratio of 3.14 (CI: 2.48, 3.98) for the PTS group versus the CB group. Whereas, the patients at high risk of POPFF had an incidence rate ratio of 9.87 (CI: 3.63, 26.80) for the PTS group versus the CB group. CONCLUSIONS: The risk of POPFF is lower when hip arthroplasty was performed using a CB stem versus a PTS stem. This protective effect was greatest in patients who had a higher risk of POPFF. Surgeons should consider the effect of cemented stem choice on the risk of subsequent periprosthetic femur fracture, particularly in frail or elderly patients who are at a higher risk of postoperative periprosthetic femoral fracture.

Higher Annual Total Hip Arthroplasty Volume Decreases the Risk of Intraoperative Periprosthetic Femur Fractures.

BACKGROUND: Periprosthetic femur fracture (PFF) is a complication of total hip arthroplasty (THA). These occur intraoperatively or postoperatively, and documented risk factors of PFFs include women, age greater than 65 years, cementless stems, and inflammatory arthropathies. The aim of this retrospective cohort study was to assess the relationship of years of surgical experience and surgeon annual THA volume on intraoperative and postoperative PFFs. METHODS: Data were collected from a database query, and PFFs were identified as either intraoperative or postoperative. Intraoperative and postoperative PFFs were both compared to a control group of non-PFF patients. Years of surgical experience at the time of surgery and annual THA volume for the primary surgeon were calculated for all cases. Logistic regression analyses were used to calculate odds ratios for each of the surgeon variables when adjusted for patient demographics. RESULTS: Thirty-seven intraoperative and 108 postoperative PFFs were identified and compared to 7,629 controls. From regression analyses, high-volume surgeons (≥50 THA/year) had lower odds of intraoperative PFF (adjusted odds ratio (aOR) = 0.40, P = .020) but not postoperative PFF (aOR = 1.02, P = .921). Surgeon experience (≥15 years since board certification at the time of surgery), was not significantly related to either PFF outcomes. For patient factors, age ≥65 years (aOR = 2.30, P < .001) and women (aOR = 2.69, P < .001) were both significant predictors of postoperative PFFs only. CONCLUSION: Surgeons who performed 50 or more THAs per year had significantly fewer intraoperative PFFs than surgeons who did less than 50 THAs per year. Surgeon experience was not significantly related to PFFs.

Acute Periprosthetic Hip Fractures With Short, Uncemented Femoral Stems.

BACKGROUND: Uncemented femoral stems in hip arthroplasty have shown excellent long-term results, and several systematic studies indicate satisfactory performance of short stems. However, biomechanical and finite element analysis studies have suggested that shorter stems allow greater micromotion, producing greater strain at the implant-bone interface, which potentially increases the risk for periprosthetic fracture (PPF). We sought to assess this risk within our unit. METHODS: Our institution's arthroplasty database was searched for all primary total hip arthroplasties using short femoral stems performed between July 14, 2009 and August 29, 2022. The overall PPF rate and the PPF rate for individual femoral stems were established. Preoperative X-rays for each case were analyzed to characterize individual proximal femoral geometry. A data analysis was performed to identify risk factors for PPF. RESULTS: For the time period assessed, 3,192 short femoral stems were implanted. This included 1,561 of stem A and 1,631 of stem B. Women constituted 55.37% of the cohort. The average patient age was 66 years (range, 22 to 95). The PPF rate was 0.6%, with 19 PPFs identified at a follow-up of 3 months. There was a significantly higher fracture rate in stem A (0.96%) compared to stem B (0.25%) (P ≤ .01). Proximal femoral geometry, age, and sex were not determined to be risk factors for PPF in our cohort. Individual surgeons and surgical approaches appeared to confer no increased risk. There was no significant difference in average stem length, but multivariate analysis identified stem type and stem length as an independent risk factor for PPF. CONCLUSIONS: Our study identified individual stem and stem length as independent risk factors for PPF within our cohort. PPF is a multifactorial issue, and consensus on emerging risk factors such as implant design will hopefully inform decisions that can provide further risk reduction for individual patients.

Osteoporosis and Total Knee Arthroplasty: Higher 5-Year Implant-Related Complications.

BACKGROUND: The risk of revision surgery in patients who have osteoporosis after total knee arthroplasty (TKA) is understudied. Our aim was to compare the 5-year cumulative risk of revision surgery after TKA in patients who have preoperative osteoporosis. METHODS: A national administrative claims database was queried for patients undergoing primary TKA from 2010 to 2021. There were 418,054 patients included, and 41,760 (10%) had osteoporosis. The 5-year incidence of revision surgery was examined for all-causes, periprosthetic fracture (PPF), aseptic loosening, and periprosthetic joint infection (PJI). A multivariable analysis was conducted using Cox proportional hazards models. Hazards ratios (HRs) were reported with 95% confidence intervals (CIs). RESULTS: The 5-year rate of all-cause revision surgery was higher for patients who had osteoporosis (HR 1.1, 95% CI: 1.0 to 1.2), however, the highest risk of revision surgery was seen for PPF (HR 1.8, 95% CI: 1.6 to 2.1). Patients who had osteoporosis also had elevated risk of revision surgery for PJI (HR 1.2, 95% CI: 1.1 to 1.3) and aseptic loosening (HR 1.2, 95% CI: 1.1 to 1.3). Osteoporosis was independently associated with PJI and aseptic loosening at a higher rate in obese patients. CONCLUSIONS: In unadjusted survival analysis, those who had osteoporosis have a marginally lower risk of all-cause revision surgery. However, after controlling for age, sex and comorbidities, patients who had osteoporosis have a nearly 2-fold increased risk of 5-year revision for PPF after TKA, and mildly increased risk of revision for all causes, aseptic loosening, and PJI. Obesity may also modulate this association. Future studies should determine the extent to which treatment of osteoporosis modifies these postoperative outcomes.

Early Periprosthetic Femur Fractures After Primary Cementless Total Hip Arthroplasty: High Risk of Periprosthetic Joint Infection and Subsequent Reoperation.

BACKGROUND: Periprosthetic femur fracture (PFF) following total hip arthroplasty (THA) is a leading cause of early reoperation. The objective of this study was to compare rates of periprosthetic joint infection (PJI) and reoperation following PFFs occurring early postoperatively to those that occurred late. METHODS: We retrospectively identified 173 consecutive surgically managed PFFs following primary THA. Cases were categorized as "early" if they occurred within 90 days of THA (n = 117) or "late" if they occurred following the initial 90 days (n = 56). Mean age at time of PFF was 68 years (range, 26 to 96) and 60% were women. Mean body mass index was 29 (range, 16 to 52). Mean follow-up was 2 years (range, 0 to 13). Kaplan-Meier survival analysis estimated cumulative incidences of PJI and reoperation. RESULTS: Early PFFs had higher 2-year cumulative incidence of PJI (11% versus 0%, P < .001) and reoperation (24% versus 13%, P = .110). Following early PFF, 27 patients required reoperation (ie, 13 for PJI, 5 for instability, 2 for re-fracture, 2 for painful hardware, 2 for non-union, 1 for adverse local tissue reaction, 1 for aseptic loosening, and 1 for leg-length discrepancy). Following late PFF, 5 patients required reoperation (ie, 3 for instability, 1 for re-fracture, and 1 for non-union). CONCLUSIONS: There are greater incidences of PJIs and overall reoperations following early PFFs compared to late PFFs after THA. In addition to focusing efforts on prevention of early PFFs, surgeons should consider antiseptic interventions to mitigate the increased risk of PJI after treatment of early PFF.

A Comparison of the Periprosthetic Fracture Rate of Cemented and Cementless Mobile Bearing Unicompartmental Knee Arthroplasties: An Analysis of Data From the National Joint Registry for England, Wales, Northern Ireland, and the Isle of Man.

BACKGROUND: Periprosthetic fractures are rare but serious complications of unicompartmental knee arthroplasty (UKA). Although cementless UKA has a lower risk of loosening than cemented, there are concerns that tibial fracture risk may be higher given the reliance on interference fit for primary stability. The risk of fracture and the effect of surgical fixation are currently unknown. We compared the periprosthetic fracture rate following cemented and cementless UKA surgery. METHODS: A total of 14,122 medial mobile-bearing UKAs (7,061 cemented and 7,061 cementless) from the National Joint Registry and Hospital Episodes Statistics database were propensity score-matched. Cumulative fracture rates were calculated and Cox regressions were used to compare fixation groups. RESULTS: The three-month periprosthetic fracture rates were similar (P = .80), being 0.10% in the cemented group and 0.11% in the cementless group. The fracture rates were highest during the first three months postoperatively, but then decreased and remained constant between one and 10 years after surgery. The one-year cumulative fracture rates were 0.2% (confidence interval [CI]: 0.1 to 0.3) for cemented and 0.2% (CI: 0.1 to 0.3) for cementless cases. The 10-year cumulative fracture rates were 0.8% (CI: 0.2 to 1.3) and 0.8% (CI: 0.3 to 1.3), respectively. The hazard ratio during the whole study period was 1.06 (CI: 0.64 to 1.77; P = .79). CONCLUSIONS: The periprosthetic fracture rate following mobile bearing UKA surgery is low, being about 1% at 10 years. There were no significant differences in fracture rates between cemented and cementless implants after matching. We surmise that surgeons are aware of the higher theoretical risk of early fracture with cementless components and take care with tibial preparation. LEVELS OF EVIDENCE: III.