The Unified Classification System (UCS) was introduced because of a growing need to have a standardised universal classification system of periprosthetic fractures. It combines and simplifies many existing classification systems, and can be applied to any fracture around any partial or total joint replacement occurring during or after operation. Our goal was to assess the inter- and intra-observer reliability of the UCS in association with knee replacement when classifying fractures affecting one or more of the femur, tibia or patella. We used an international panel of ten orthopaedic surgeons with subspecialty fellowship training and expertise in adult hip and knee reconstruction (‘experts’) and ten residents of orthopaedic surgery in the last two years of training (‘pre-experts’). They each received 15 radiographs for evaluation. After six weeks they evaluated the same radiographs again but in a different order. . The reliability was assessed using the Kappa and weighted Kappa values. The Kappa values for inter-observer reliability for the experts and the pre-experts were 0.741 (95% confidence interval (CI) 0.707 to 0.774) and 0.765 (95% CI 0.733 to 0.797), respectively. The weighted Kappa values for intra-observer reliability for the experts and pre-experts were 0.898 (95% CI 0.846 to 0.950) and 0.878 (95% CI 0.815 to 0.942) respectively. The UCS has substantial inter-observer reliability and ‘near perfect’ intra-observer reliability when used for periprosthetic fractures in association with knee replacement in the hands of experienced and inexperienced users. Cite this article: Bone Joint J 2014;96-B:1669–73

Aims. This aim of this study was to assess the reliability and validity of the Unified Classification System (UCS) for postoperative periprosthetic femoral fractures (PFFs) around cemented polished taper-slip (PTS) stems. Methods. Radiographs of 71 patients with a PFF admitted consecutively at two centres between 25 February 2012 and 19 May 2020 were collated by an independent investigator. Six observers (three hip consultants and three trainees) were familiarized with the UCS. Each PFF was classified on two separate occasions, with a mean time between assessments of 22.7 days (16 to 29). Interobserver reliability for more than two observers was assessed using percentage agreement and Fleiss’ kappa statistic. Intraobserver reliability between two observers was calculated with Cohen kappa statistic. Validity was tested on surgically managed UCS type B PFFs where stem stability was documented in operation notes (n = 50). Validity was assessed using percentage agreement and Cohen kappa statistic between radiological assessment and intraoperative findings. Kappa statistics were interpreted using Landis and Koch criteria. All six observers were blinded to operation notes and postoperative radiographs. Results. Interobserver reliability percentage agreement was 58.5% and the overall kappa value was 0.442 (moderate agreement). Lowest kappa values were seen for type B fractures (0.095 to 0.360). The mean intraobserver reliability kappa value was 0.672 (0.447 to 0.867), indicating substantial agreement. Validity percentage agreement was 65.7% and the mean kappa value was 0.300 (0.160 to 0.4400) indicating only fair agreement. Conclusion. This study demonstrates that the UCS is unsatisfactory for the classification of PFFs around PTS stems, and that it has considerably lower reliability and validity than previously described for other stem types. Radiological PTS stem loosening in the presence of PFF is poorly defined and formal intraoperative testing of stem stability is recommended. Cite this article: Bone Joint J 2021;103-B(8):1339–1344

The Unified Classification System (UCS) emphasises the key principles in the assessment and management of peri-prosthetic fractures complicating partial or total joint replacement. We tested the inter- and intra-observer agreement for the UCS as applied to the pelvis and femur using 20 examples of peri-prosthetic fracture in 17 patients. Each subtype of the UCS was represented by at least one case. Specialist orthopaedic surgeons (experts) and orthopaedic residents (pre-experts) assessed reliability on two separate occasions. For the pelvis, the UCS showed inter-observer agreement of 0.837 (95% confidence intervals (CI) 0.798 to 0.876) for the experts and 0.728 (95% CI 0.689 to 0.767) for the pre-experts. The intra-observer agreement for the experts was 0.861 (95% CI 0.760 to 0.963) and 0.803 (95% 0.688 to 0.918) for the pre-experts. For the femur, the UCS showed an inter-observer kappa value of 0.805 (95% CI 0.765 to 0.845) for the experts and a value of 0.732 (95% CI 0.690 to 0.773) for the pre-experts. The intra-observer agreement was 0.920 (95% CI 0.867 to 0.973) for the experts, and 0.772 (95% CI 0.652 to 0.892) for the pre-experts. This corresponds to a substantial and ‘almost perfect’ inter- and intra-observer agreement for the UCS for peri-prosthetic fractures of the pelvis and femur. We hope that unifying the terminology of these injuries will assist in their assessment, treatment and outcome. Cite this article: Bone Joint J 2014;96-B:1472–7

Aims. Periprosthetic fractures (PPFs) around the knee are challenging injuries. This study aims to describe the characteristics of knee PPFs and the impact of patient demographics, fracture types, and management modalities on in-hospital mortality. Methods. Using a multicentre study design, independent of registry data, we included adult patients sustaining a PPF around a knee arthroplasty between 1 January 2010 and 31 December 2019. Univariate, then multivariable, logistic regression analyses were performed to study the impact of patient, fracture, and treatment on mortality. Results. Out of a total of 1,667 patients in the PPF study database, 420 patients were included. The in-hospital mortality rate was 6.4%. Multivariable analyses suggested that American Society of Anesthesiologists (ASA) grade, history of peripheral vascular disease (PVD), history of rheumatic disease, fracture around a loose implant, and cerebrovascular accident (CVA) during hospital stay were each independently associated with mortality. Each point increase in ASA grade independently correlated with a four-fold greater mortality risk (odds ratio (OR) 4.1 (95% confidence interval (CI) 1.19 to 14.06); p = 0.026). Patients with PVD have a nine-fold increase in mortality risk (OR 9.1 (95% CI 1.25 to 66.47); p = 0.030) and patients with rheumatic disease have a 6.8-fold increase in mortality risk (OR 6.8 (95% CI 1.32 to 34.68); p = 0.022). Patients with a fracture around a loose implant (Unified Classification System (UCS) B2) have a 20-fold increase in mortality, compared to UCS A1 (OR 20.9 (95% CI 1.61 to 271.38); p = 0.020). Mode of management was not a significant predictor of mortality. Patients managed with revision arthroplasty had a significantly longer length of stay (median 16 days; p = 0.029) and higher rates of return to theatre, compared to patients treated nonoperatively or with fixation. Conclusion. The mortality rate in PPFs around the knee is similar to that for native distal femur and neck of femur fragility fractures. Patients with certain modifiable risk factors should be optimized. A national PPF database and standardized management guidelines are currently required to understand these complex injuries and to improve patient outcomes. Cite this article: Bone Joint J 2024;106-B(2):158–165

Aims. The aim of this study was to compare open reduction and internal fixation (ORIF) with revision surgery for the surgical management of Unified Classification System (UCS) type B periprosthetic femoral fractures around cemented polished taper-slip femoral components following primary total hip arthroplasty (THA). Methods. Data were collected for patients admitted to five UK centres. The primary outcome measure was the two-year reoperation rate. Secondary outcomes were time to surgery, transfusion requirements, critical care requirements, length of stay, two-year local complication rates, six-month systemic complication rates, and mortality rates. Comparisons were made by the form of treatment (ORIF vs revision) and UCS type (B1 vs B2/B3). Kaplan-Meier survival analysis was performed with two-year reoperation for any reason as the endpoint. Results. A total of 317 periprosthetic fractures (in 317 patients) with a median follow-up of 3.6 years (interquartile range (IQR) 2.0 to 5.4) were included. The fractures were type B1 in 133 (42.0%), B2 in 170 (53.6%), and B3 in 14 patients (4.4%). ORIF was performed in 167 (52.7%) and revision in 150 patients (47.3%). The two-year reoperation rate (15.3% vs 7.2%; p = 0.021), time to surgery (4.0 days (IQR 2.0 to 7.0) vs 2.0 days (IQR 1.0 to 4.0); p < 0.001), transfusion requirements (55 patients (36.7%) vs 42 patients (25.1%); p = 0.026), critical care requirements (36 patients (24.0%) vs seven patients (4.2%); p < 0.001) and two-year local complication rates (26.7% vs 9.0%; p < 0.001) were significantly higher in the revision group. The two-year rate of survival was significantly higher for ORIF (91.9% (standard error (SE) 0.023%) vs 83.9% (SE 0.031%); p = 0.032) compared with revision. For B1 fractures, the two-year reoperation rate was significantly higher for revision compared with ORIF (29.4% vs 6.0%; p = 0.002) but this was similar for B2 and B3 fractures (9.8% vs 13.5%; p = 0.341). The most common indication for reoperation after revision was dislocation (12 patients; 8.0%). Conclusion. Revision surgery has higher reoperation rates, longer surgical waiting times, higher transfusion requirements, and higher critical care requirements than ORIF in the management of periprosthetic fractures around polished taper-slip femoral components after THA. ORIF is a safe option providing anatomical reconstruction is achievable. Cite this article: Bone Joint J 2023;105-B(2):124–134

Aims. The aim of this study was to describe the demographic details of patients who sustain a femoral periprosthetic fracture (PPF), the epidemiology of PPFs, PPF characteristics, and the predictors of PPF types in the UK population. Methods. This is a multicentre retrospective cohort study including adult patients presenting to hospital with a new PPF between 1 January 2018 and 31 December 2018. Data collected included: patient characteristics, comorbidities, anticoagulant use, social circumstances, level of mobility, fracture characteristics, Unified Classification System (UCS) type, and details of the original implant. Descriptive analysis by fracture location was performed, and predictors of PPF type were assessed using mixed-effects logistic regression models. Results. In total, 720 femoral PPFs from 27 NHS sites were included. PPF patients were typically elderly (mean 79.9 years (SD 10.6)), female (n = 455; 63.2%), had at least one comorbidity (n = 670; 93.1%), and were reliant on walking aids or bed-/chair-bound prior to admission (n = 419; 61.7%). The study population included 539 (74.9%) hip PPFs, 151 (21.0%) knee PPFs, and 30 (4.2%) dividing type PPFs. For hip (n = 407; 75.5%) and knee (n = 88; 58.3%) arthroplasty UCS B type fractures were most common. Overall, 556 (86.2%) were treated in the presenting hospital and 89 (13.8%) required transfer for treatment. Female sex was the only significant predictor of fracture type (A/B1/C type versus B2/B3) for femoral hip PPFs (odds ratio 0.61 (95% confidence interval 0.41 to 0.91); p = 0.014). Sex, residence type, primary versus revision implant PPF, implant fixation, and time between arthroplasty and PPF were not found to predict fracture type for hip PPFs. Conclusion. This multicentre analysis describes patient and injury factors for patients presenting with femoral PPFs to centres across the UK. These patients are generally elderly and frail, comparable to those sustaining a hip fracture. These data can be useful in planning future services and clinical trials. Cite this article: Bone Joint J 2022;104-B(8):987–996

The Unified Classification System (UCS), or Vancouver system, is a validated and widely used classification system to guide the management of periprosthetic femoral fractures. It suggests that well-fixed stems (type B1) can be treated with fixation but that loose stems (types B2 and B3) should be revised. Determining whether a stem is loose can be difficult and some authors have questioned how to apply this classification system to polished taper slip stems which are, by definition, loose within their cement mantle. Recent evidence has challenged the common perception that revision surgery is preferable to fixation surgery for UCS-B periprosthetic fractures around cemented polished taper slip stems. Indications for fixation include an anatomically reducible fracture and cement mantle, a well-fixed femoral bone-cement interface, and a well-functioning acetabular component. However, not all type B fractures can or should be managed with fixation due to the risk of early failure. This annotation details specific fracture patterns that should not be managed with fixation alone.

Cite this article: Bone Joint J 2023;105-B(5):481–486.

Periprosthetic femoral fractures are increasing in incidence, and typically occur in frail elderly patients. They are similar to pathological fractures in many ways. The aims of treatment are the same, including 'getting it right first time' with a single operation, which allows immediate unrestricted weightbearing, with a low risk of complications, and one that avoids the creation of stress risers locally that may predispose to further peri-implant fracture. The surgical approach to these fractures, the associated soft-tissue handling, and exposure of the fracture are key elements in minimizing the high rate of complications. This annotation describes the approaches to the femur that can be used to facilitate the surgical management of peri- and interprosthetic fractures of the femur at all levels using either modern methods of fixation or revision arthroplasty.

Cite this article: Bone Joint J 2023;105-B(6):593–601.

Aims

The aim of this study was to determine both the incidence of, and the reoperation rate for, postoperative periprosthetic femoral fracture (POPFF) after total hip arthroplasty (THA) with either a collared cementless (CC) femoral component or a cemented polished taper-slip (PTS) femoral component.

Polished taper-slip (PTS) cemented stems have an excellent clinical track record and are the most common stem type used in primary total hip arthroplasty (THA) in the UK. Due to low rates of aseptic loosening, they have largely replaced more traditional composite beam (CB) cemented stems. However, there is now emerging evidence from multiple joint registries that PTS stems are associated with higher rates of postoperative periprosthetic femoral fracture (PFF) compared to their CB stem counterparts. The risk of both intraoperative and postoperative PFF remains greater with uncemented stems compared to either of these cemented stem subtypes. PFF continues to be a devastating complication following primary THA and is associated with high complication and mortality rates. Recent efforts have focused on identifying implant-related risk factors for PFF in order to guide preventative strategies, and therefore the purpose of this article is to present the current evidence on the effect of cemented femoral stem design on the risk of PFF.

Cite this article: Bone Joint J 2024;106-B(1):11–15.

Aims

The aim of this study was to describe the management and associated outcomes of patients sustaining a femoral hip periprosthetic fracture (PPF) in the UK population.

Aims

The aim of this study was to investigate the outcome of periprosthetic fractures of the humerus and to assess the uniformity of the classifications used for these fractures (including those around elbow and/or shoulder arthroplasties) by performing a systematic review of the literature.

Aims

The prevalence of ipsilateral total hip arthroplasty (THA) and total knee arthroplasty (TKA) is rising in concert with life expectancy, putting more patients at risk for interprosthetic femur fractures (IPFFs). Our study aimed to assess treatment methodologies, implant survivorship, and IPFF clinical outcomes.

Periprosthetic fractures are an increasingly common complication following joint replacement. The principles which underpin their evaluation and treatment are common across the musculoskeletal system. The Unified Classification System proposes a rational approach to treatment, regardless of the bone that is broken or the joint involved.

Cite this article: Bone Joint J 2014;96-B:713–16.