B2 or not B2? That is the question: a review of periprosthetic fractures around cemented taper-slip femoral components

Periprosthetic Femoral Fractures-Beyond B2

The proliferation of hip arthroplasty has seen concomitant increases in periprosthetic femoral fractures (PFFs). The most common pattern involves fracture at the level of a loose prosthesis (B2). B2 PFFs have a unique mechanopathogenesis linked to the tendency of polished taper-slip cemented stems to subside in the cement. Such stems carry a much higher PFF risk than other cemented designs. Mega-data, consistent across national registries, suggest that increasing application of the taper-slip principle has resulted in the emergence of highly polished, very low friction cemented prostheses. These have the propensity to migrate within the cement, increasing B2 PFF risk. This would explain the strong association between cobalt-chromium stems and PFF. Is PFF the mode of failure of polished taper-slip stems rather than aseptic loosening? Established wisdom teaches that B2 PFFs should be managed with revision surgery. There is a large body of new evidence that, in certain instances, fixation results in outcomes at least equivalent to revision arthroplasty, with shorter surgical time, decreased transfusion requirements, and lower dislocation risk. This is so in B2 PFFs around cemented polished taper-slip stems with an intact bone-cement interface. We outline advances in understanding of B2 PFF with special reference to mechanopathogenesis and indications for fixation.

Comparative outcomes of uncemented and cemented stem revision in managing periprosthetic femoral fractures: a retrospective cohort study

INTRODUCTION

Periprosthetic femoral fractures (PFFs) following hip arthroplasty, especially Vancouver B2 and B3 fractures, present a challenge due to the association with a loose femoral stem, necessitating either open reduction and internal fixation or stem revision. This study aims to compare outcomes between uncemented and cemented stem revisions in managing Vancouver B2 and B3 fractures, considering factors such as hip-related complications, reoperations, and clinical outcome.

METHODS

A retrospective cohort study was conducted at Danderyd Hospital, Sweden, from 2008 to 2022, encompassing operatively treated Vancouver B2 and B3 fractures. Patients were categorized into uncemented and cemented stem revision groups, with data collected on complications, revision surgeries, fracture healing times, and clinical outcomes.

RESULTS

A total of 241 patients were identified. Significant differences were observed between the two groups in patient demographics, with the cemented group comprising older patients and more females. Follow up ranged from 1 to 15 years. Average follow up time was 3.9 years for the cemented group and 5.5 years for the uncemented group. The cemented stems demonstrated lower rates of dislocation (8.9% versus 22.5%, P = 0.004) and stem loosening (0.6% versus 9.3%, P = 0.004) than the uncemented method. Moreover, the cemented group exhibited shorter fracture healing times (11.4 weeks versus 16.7 weeks, P = 0.034). There was no difference in clinical outcome between groups. Mortality was higher in the cemented group.

CONCLUSIONS

This retrospective study indicates that cemented stem revision for Vancouver B2-3 fractures is correlated with lower dislocation and stem loosening rates, necessitating fewer reoperations and shorter fracture healing times compared with the uncemented approach. The cemented group had a notably higher mortality rate, urging caution in its clinical interpretation.

LEVEL OF EVIDENCE III

The burden of periprosthetic femoral fractures in England and Wales: Insights from the first two years of data collection in the National Hip Fracture Database and regional variation in care

INTRODUCTION

Periprosthetic femoral fractures (PPFFs) represent an important healthcare problem, with a rising incidence noted due to an increase in the number of arthroplasty surgeries being performed. There is a current lack of national consensus as to how these complex, often frail patients are managed.

AIMS

Our primary aim was to present the epidemiology of PPFFs in England and Wales over the first two years of data collection by the National Hip Fracture Database (NHFD). Secondary aims included how well the NHFD Key Performance Indicators (KPIs) are met for PPFF patients, whether centres reporting a higher burden of PPFF patients are more likely to meet KPIs compared to lower volume centres, and to also identify if regional variation in care for these patients exist.

METHODS

Patients aged 60 years or over, admitted to any acute hospital in England or Wales with a PPFF within the period 1st January 2020 to 31st December 2021 were included. Fractures were classified using the Vancouver system. The primary outcome of interest was the incidence of PPFF in England and Wales. Secondary outcomes included i) geographical distribution, ii) pattern of injury, iii) treatment received, iv) KPI performance nationally, v) KPI performance by top 5 highest volume hospitals vs the rest, vi) KPI performance by region and vii) KPI performance compared with native hip fracture patients.

RESULTS

A total of 5,566 PPFFs were reported during our study period. A 31 % increase in cases was seen between 2020 and 2021 (2,405 to 3,161). The South-West of England reported the highest burden of PPFFs (14 % of all cases reported in 2021). Vancouver B subtypes were most common around hip replacements (62 %) and C subtype around knee replacements (55 %). A total of 4,598 patients (82.6 %) underwent operative management. There was regional variation in KPI attainment. When compared to KPI attainment for native hip fractures PPFF care under performed in most regions and domains. High volume PPFF centres were not associated with improved attainment of KPIs.

CONCLUSION

We have described the incidence, nature, and management of PPFF at national and regional levels using routinely collected NHFD data. Both numerically and due to case complexity, PPFF are a considerable challenge to patients and health services alike. This epidemiology is not captured by other existing datasets and increased case contribution to the NHFD is encouraged to improve understanding and enable prioritisation and delivery of further care and research.

Health status after periprosthetic proximal femoral fractures

Aims

Periprosthetic proximal femoral fractures (PFFs) are a major complication after total hip arthroplasty (THA). Health status after PFF is not specifically investigated. The aim of this study is to evaluate the health status pattern over two years after sustaining a PFF.

Methods

A cohort of patients with PFF after THA was derived from the Brabant Injury Outcomes Surveillance (BIOS) study. The BIOS study, a prospective, observational, multicentre follow-up cohort study, was conducted to obtain data by questionnaires pre-injury and at one week, and one, three, six, 12, and 24 months after trauma. Primary outcome measures were the EuroQol five-dimension three-level questionnaire (EQ-5D-3L), the Health Utility Index 2 (HUI2), and the Health Utility Index 3 (HUI3). Secondary outcome measures were general measurements such as duration of hospital stay and mortality.

Results

A total of 70 patients with a PFF were included. EQ-5D utility scores were significantly lower on all timepoints except at six months' follow-up compared to pre-injury. EuroQol visual analogue scale (EQ-VAS) scores at one month's follow-up were significantly lower compared to pre-injury. The percentage of reported problems at two years was higher for all dimensions except anxiety/depression when compared to pre-injury. The mean EQ-5D utility score was 0.26 higher in males compared to females (95% confidence interval (CI) 0.01 to 0.42; p = 0.003). The mean EQ-VAS score for males was 8.9 points higher when compared to females over all timepoints (95% CI 1.2 to 16.7; p = 0.027). Mortality was 10% after two years' follow-up.

Conclusion

PFF patients are a frail population with substantial functional impairment at baseline. Post-injury, they have a significant and clinically relevant lower health status two years after trauma when compared to pre-injury. Health status improves the most between one and three months after injury. Two years after PFF, more patients experience problems in mobility, self-care, usual activities, and pain/discomfort than pre-injury.

Impaction bone grafting for femoral revision hip arthroplasty with Exeter stem in Japan: An extended 10- to 15-year stem survival analysis of the previously reported series

BACKGROUND

Femoral impaction bone grafting (IBG) was introduced in the late 1990s in Japan and has gradually become recognized as a useful option for femoral revision. The aim of the present study was to retrospectively analyze 10 to 15 years of clinical results of femoral revision arthroplasties of IBG using Exeter stem performed by experienced Japanese surgeons.

METHODS

We investigated radiographic and clinical records more than 2 years after surgery in 99 hips of 93 patients. The average age was 66.3 years (36-84 years) and the average follow-up period was 11 years (2-23 years and 8 months). Merle d'Aubigné and Postel hip score was used for clinical assessment, and re-operations for any reason were recorded. The survival curve was estimated using Kaplan-Meier method.

RESULTS

The mean Merle d'Aubigné and Postel hip score improved from 9.0 points to 14.5 points at the final follow-up. Re-operations were undertaken in 15 hips of 14 patients for aseptic acetabular component loosening (n = 1 hip), recurrent dislocation (n = 2 hips), infection (n = 4 hips), and periprosthetic femoral fracture (n = 8 hips). The survival rates at 10 and 15 years after operation were 87.1% and 81.1% with any type of re-operation as the endpoint, 92.2% and 92.2% with stem removal or exchange as the endpoint, 94.9% and 88.1% with re-operation for periprosthetic femoral fracture as the endpoint, and 99.0% and 99.0% with re-operation for aseptic stem loosening as the endpoint, respectively.

CONCLUSIONS

The present study showed encouraging results of femoral IBG over 10 years by experienced surgeons in Japan. Although femoral IBG is recognized as a technically complex procedure, survivorship of the stem is excellent, with a 15-year stem survival rate of 99.0% at the end point of aseptic loosening.

Cemented femoral stem design and postoperative periprosthetic fracture risk following total hip arthroplasty

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.

A comparison of mortality rates following revision hip arthroplasty for periprosthetic fracture, infection or aseptic loosening

BACKGROUND

Mortality following revision hip surgery for periprosthetic fracture (PPF) is comparable to neck of femur fractures. Our institution provides a regional "PPF Service". The aim of this study was to determine the time to surgery and mortality rate for PPF, compared to revision for infection or aseptic loosening.

METHODS

Revision arthroplasty procedures performed for PPF, infection or aseptic loosening between January 2014 and December 2015 were identified. Comparisons were made between the 3 groups for baseline demographics, admission to higher-level care, length of stay, complications and mortality.

RESULTS

There were 37 PPF, 71 infected and 221 aseptic revisions. PPF had a higher proportion of females (65% vs. 39% in infection and 53% in aseptic; p = 0.031) and grade 3 and 4 ASA patients (p = 0.006). Median time to surgery for PPF was 8 days (95% CI, 6-16). Single-stage procedures were performed in 84% of PPF, 42% of infections and 99% of aseptic revisions (p < 0.001). 19% of PPF revisions required HDU admission, 1% in the aseptic group and none in the infection group. Median length of stay was significantly different (PPF 10; infection 14; aseptic 8 days (p < 0.001). The 1-year mortality rate for PPF was 0%, 2.8% for infection and 0.9% in the aseptic group (p = 0.342).

CONCLUSIONS

Despite the PPF group having higher ASA grades and more HDU admissions, our 1-year mortality rate was 0% and not significantly different to infection or aseptic loosening. Our low complication and 1-year mortality rate is encouraging and supports the safety of a regional "Periprosthetic Fracture Service".

Patient and technical contributors to periprosthetic fracture around the CPT stem

INTRODUCTION

The incidence of postoperative periprosthetic fracture has been reported to be higher in polished tapered femoral stems with the CPT stem possibly of greatest concern. We report on the patient and surgical factors in a consecutive cohort of 2892 CPT stems implanted as part of a total hip construct, either electively or for the treatment of a fractured neck of femur (NOF) over a 15-year period.

METHODS

The Bluespier departmental database was used to identify any patients who been treated for a Vancouver B periprosthetic fracture around a CPT stem from 2008 to 2021. Patient demographics, mechanism of injury and fracture type were recorded. X-rays were reviewed to identify technical issues that may have contributed to the fracture.

RESULTS

A total of 70 fractures were treated. For elective cases the fracture rate was 1.52% while for stems implanted for treatment of a neck of femur fracture (NOF) it was 2.86%. There was a male preponderance and almost all fractures were low energy. The majority (52.9%) were B1 fractures. Only 8 (11.4%) involved a truly loose construct (B2L). The presence of an undersized and varus stem increased the risk of fracture particularly in the NOF population.

DISCUSSION

The results in this series are consistent with the registry data regarding the rate of failure of the CPT stem related to periprosthetic fracture. The patient population is typical of those who sustain a proximal femoral fracture in terms of age although we report a male preponderance. The importance of surgical technique in the placement of a correctly sized and aligned stem, particularly in those patients undergoing hip replacement for a neck of femur fracture is highlighted.

Epidemiology of revision hip replacement surgery in the UK over the past 15 years-an analysis from the National Joint Registry

OBJECTIVES

To investigate trends in the incidence rate and main indication for revision hip replacement (rHR) over the past 15 years in the UK.

DESIGN

Repeated national cross-sectional study from 2006 to 2020.

SETTING/PARTICIPANTS

rHR procedures were identified from the National Joint Registry for England, Wales, Northern Ireland, the Isle of Man and the States of Guernsey. Population statistics were obtained from the Office for National Statistics.

MAIN OUTCOME MEASURES

Crude incidence rates of rHR.

RESULTS

The incidence rate of rHR doubled from 11 per 100 000 adults in 2006 (95% CI 10.7 to 11.3) to a peak of 22 per 100 000 adults (95% CI 22 to 23) in 2012, before falling to 17 per 100 000 adults in 2019 (95% CI 16 to 17) (24.5% decrease from peak). The incidence rate of rHR reduced by 39% in 2020 compared with 2019 (during the COVID-19 pandemic). The most frequent indications for rHR between 2006 and 2019 were loosening/lysis (27.8%), unexplained pain (15.1%) and dislocation/instability (14.7%). There were incremental increases in the annual number and incidence rates of rHR for fracture, infection, dislocation/instability and a decrease in rHR for aseptic loosening/lysis.

CONCLUSIONS

The incidence rate of rHR doubled from 2006 to 2012, likely due to high early failure rates of metal-on-metal hip replacements. The incidence of rHR then decreased by approximately 25% from 2012 to 2019, followed by a large decrease during the COVID-19 pandemic. The decrease in the number of rHR performed for aseptic loosening/lysis may reflect improved wear and implant longevity. Increased healthcare resource will be required to care for the increasing numbers of patients undergoing rHR for fracture and infection.

Effect of Fracture Type, Treatment, and Surgeon Training on Reoperation After Vancouver B Periprosthetic Femur Fractures

BACKGROUND

The treatment of Vancouver B periprosthetic proximal femur fractures (PPFFs) is complex due to the overlap between arthroplasty and orthopedic trauma techniques. Our purpose was to assess the effects of fracture type, treatment difference, and surgeon training on the risk of reoperation in Vancouver B PPFF.

METHODS

A collaborative research consortium of 11 centers retrospectively reviewed PPFFs from 2014 to 2019 to determine the effects of variations in surgeon expertise, fracture type, and treatment on surgical reoperation. Surgeons were classified as per fellowship training, fractures using the Vancouver classification, and treatment as open reduction internal fixation (ORIF) or revision total hip arthroplasty with or without ORIF. Regression analyses were performed with reoperation as the primary outcome.

RESULTS

Fracture type (Vancouver B3 versus B1: odds ratio [OR]: 5.70) was an independent risk factor for reoperation. No differences were found in reoperation rates with treatment (ORIF versus revision: OR 0.92, P = .883). Treatment by a nonarthroplasty-trained surgeon versus an arthroplasty specialist led to higher odds of reoperation in all Vancouver B fracture (OR: 2.87, P = .023); however, no significant differences were seen in the Vancouver B2 group alone (OR: 2.61, P = .139). Age was a significant risk factor for reoperation in all Vancouver B fractures (OR: 0.97, P = .004) and in the B2 fractures alone (OR: 0.96, P = .007).

CONCLUSION

Our study suggests that age and fracture type affect reoperation rates. Treatment type did not affect reoperation rates and the effect of surgeon training is unclear.

Monoblock tapered stems in management of UCS B2 and B3 periprosthetic fractures in revision total hip arthroplasty

Aims

United Classification System (UCS) B2 and B3 periprosthetic fractures in total hip arthroplasties (THAs) have been commonly managed with modular tapered stems. No study has evaluated the use of monoblock fluted tapered titanium stems for this indication. This study aimed to evaluate the effects of a monoblock stems on implant survivorship, postoperative outcomes, radiological outcomes, and osseointegration following treatment of THA UCS B2 and B3 periprosthetic fractures.

Methods

A retrospective review was conducted of all patients who underwent revision THA (rTHA) for periprosthetic UCS B2 and B3 periprosthetic fracture who received a single design monoblock fluted tapered titanium stem at two large, tertiary care, academic hospitals. A total of 72 patients met inclusion and exclusion criteria (68 UCS B2, and four UCS B3 fractures). Primary outcomes of interest were radiological stem subsidence (> 5 mm), radiological osseointegration, and fracture union. Sub-analysis was also done for 46 patients with minimum one-year follow-up.

Results

For the total cohort, stem osseointegration, fracture union, and stem subsidence were 98.6%, 98.6%, and 6.9%, respectively, at latest follow-up (mean follow-up 27.0 months (SD 22.4)). For patients with minimum one-year of follow-up, stem osseointegration, fracture union, and stem subsidence were 97.8%, 97.8%, and 6.5%, respectively.

Conclusion

Monoblock fluted stems can be an acceptable modality for the management of UCS B2 periprosthetic fractures in rTHAs due to high rates of stem osseointegration and survival, and the low rates of stem subsidence, and revision. Further research on the use of this stem for UCS B3 periprosthetic fractures is warranted to determine if the same conclusion can be made for this fracture pattern.

Subsidence in Centraliser Sign: A Novel Tool to Help Predict Early Subsidence in Periprosthetic Femoral Fractures Around Polished Tapered Stems Treated With Internal Fixation

Background When treating periprosthetic femoral fractures (PPF) around polished taper slip stems (PTS), determining which patients can be successfully treated with internal fixation can be challenging. We have described the subsidence-in-centraliser (SINC) sign as a radiographic feature of PPF around PTS stems. We hypothesise that a positive SINC sign can help predict a poorer outcome for the fixation of these fractures. Patients and methods Retrospective identification of PPFs around cemented PTS with an appreciable centraliser on radiographs was conducted at a single centre. A positive SINC sign was defined as a post-injury radiograph demonstrating >50% reduction in the radiographic lucency representing the stem centraliser when compared to pre-injury films or complete obliteration of distal lucency when no pre-injury film was available. The primary outcome was the rate of subsequent stem subsidence on follow-up radiographs comparing SINC-positive and SINC-negative fractures, which were managed with open reduction and internal fixation (ORIF). Results Fifty-four patients were included in the analysis. The mean age was 76.8 years, and the mean follow-up for all patients was 12.7 months. Thirty-five fractures were deemed SINC-positive, and 19 were SINC-negative. 17/17 (100%) SINC-positive fractures managed with fixation underwent further subsidence (mean 5.4 mm, SD 2.8). A positive SINC sign demonstrated a sensitivity of 90.5% and specificity of 100% for subsequent stem subsidence in fractures treated without revision. SINC positive fractures underwent significantly more subsidence compared with SINC negative fractures when fixed (5.4 mm vs. 0.28 mm, U = 6.50, p<0.001) at a mean follow-up of 12.7 months. The SINC sign demonstrated strong inter- (k=0.96) and intra-rater (k=0.86) reliability. Conclusion The SINC sign can serve as a useful adjunct in the decision to fix or revise PPF around PTS. A positive SINC sign may represent a cement mantle that cannot be reconstituted anatomically, leading to subsidence after treatment with ORIF.

Which Unified Classification System type B periprosthetic fractures around cemented polished tapered stems should not be fixed?

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.

Factors associated with failure of fixation of Vancouver B fractures around a cemented polished tapered stem: A 5 to 14 year follow up study

AIMS

There is increasing evidence for fixation as opposed to revision for Vancouver B fractures around polished taper slip stems, however it is remains unclear whether fixation is associated with stem loosening in the longer term. This study aims to assess survival of plate-fixation of Vancouver-B-fractures around a polished-taper- slip cemented stem and identify factors associated with failure.

METHODS

Retrospective cohort study assessed 129 consecutive unilateral Vancouver-B-fractures around cemented Exeter stems at a minimum of 5 years following open-reduction-internal-fixation (ORIF) with unilateral non-locked unilateral plating+/-cerclage cables. The primary outcome measure was reoperation for any reason. Kaplan Meier survival analysis was performed.

RESULTS

Fractures (B1 n = 31 (24%); B2 n = 91 (71%); and B3 n = 7 (5%)) occurred at median of 6 years (IQR 1.2-9.2) after primary surgery. Mean patient age was 78.2 (SD10.56, range 46-96) and 54 (42.9%) were female. Mean follow up was 8.7 years (SD 2.48, 5.7 to 14.4). Symptomatic femoral stem loosening requiring revision occurred in two B2 fractures of metaphyseal split and short spiral patterns. The most common mode of failure was non-union (n = 7, 5%). Both fixation failure (n = 6/31 Vs n = 3/91 vs n = 0/7, p = 0.008) and reoperation (n = 8/31 vs n = 6/91 vs n = 0/7, p = 0.008) were significantly higher following fixation of B1 fractures compared to B2 and B3 fractures. Overall 5year survival free from reoperation was 88.8% (82.0-94.7 95%CI). B1 fracture types were associated with an increase risk of failure (endpoints fixation failure p = 0.010; and reoperation p = 0.016). Transverse fractures (B1) were associated with a relative risk of reoperation of 4.22 (1.63-10.9 95% CI, p = 0.008).

CONCLUSION

Fixation of Vancouver-B fractures around cemented Exeter stems, when the bone-cement interface is intact and the fracture is anatomically reducible, had an excellent 5-year survival. Only 2 (1.6%) cases of late femoral stem loosening occurred, however, B1 type transverse fractures were associated with a higher rate of reoperation.

A multicentre comparative analysis of fixation versus revision surgery for periprosthetic femoral fractures following total hip arthroplasty with a cemented polished taper-slip femoral component

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.

Periprosthetic femoral fractures around the original cemented polished triple-tapered C-stem femoral implant: a consecutive series of 500 primary total hip arthroplasties with an average follow-up of 15 years

INTRODUCTION

The true incidence of periprosthetic femoral fracture (PFF) around cemented polished taper-slip implants remains largely unknown. Registries usually only capture PFFs that result in revision, missing those managed non-operatively or treated by open reduction and internal fixation (ORIF). This study reports the long-term rate of PFF with the original triple-tapered C-stem femoral implant.

MATERIALS AND METHODS

A prospective review of a consecutive series of 500 primary total hip arthroplasties (THAs) performed at a single centre between March 2000 and December 2005, with average follow-up of 15 years (12-19 years).

RESULTS

There were 500 consecutive THAs in 455 patients. Seven PFFs (1.4%) occurred in seven patients at an average of 7.9 years (range 2-11.5) from the primary arthroplasty. Five PFFs were managed by ORIF, one Vancouver B3 fracture was revised for a loose implant and one patient was treated non-operatively. Average age at primary operation was 74 years (67-87) and BMI averaged 27.3 (22-31). There was no typical fracture pattern and no statistically significant associations with patient demographics (age, gender, BMI, diagnosis) or prosthetic details (size, offset, alignment, cement mantle, subsidence). Survivorship to the occurrence of PFF was 99% (97.3-99.6%) at 10 years and 97.8% (95.5-99.0%) at 15.

CONCLUSION

A PFF rate of 1.4% at an average follow-up of 15 years represents the true incidence of PFF with the use of the original triple-tapered C-Stem femoral implant, similar to that of published Exeter series (1.85%) but lower than the CPT (3.3%).

Periprosthetic Infection in the Setting of Periprosthetic Total Hip Fractures: Evaluation and Management

The incidences of periprosthetic fracture and periprosthetic joint infection after total hip arthroplasty are expected to increase exponentially over the coming decades. Epidemiologic data suggest that many periprosthetic fractures after THA occur concurrently with a loose femoral implant. Recent studies suggest an approximately 8% incidence of indolent infection in cases of suspected aseptic loosening. The available data, therefore, suggest that periprosthetic fracture and infection may coexist, and this possibility should be considered, particularly in patients with a loose femoral stem and high pretest possibility. Although currently limited, the available literature provides some guidance as how to manage this complex issue.

Reliability and validity of the Unified Classification System for postoperative periprosthetic femoral fractures around cemented polished taper-slip stems

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.

Selected Vancouver B2 periprosthetic femoral fractures around cemented polished femoral components can be safely treated with osteosynthesis

AIMS

We aimed to compare the implant survival, complications, readmissions, and mortality of Vancouver B2 periprosthetic femoral fractures (PFFs) treated with internal fixation with that of B1 PFFs treated with internal fixation and B2 fractures treated with revision arthroplasty.

METHODS

We retrospectively reviewed the data of 112 PFFs, of which 47 (42%) B1 and 27 (24%) B2 PFFs were treated with internal fixation, whereas 38 (34%) B2 fractures underwent revision arthroplasty. Decision to perform internal fixation for B2 PFFs was based on specific radiological (polished femoral components, intact bone-cement interface) and clinical criteria (low-demand patient). Median follow-up was 36.4 months (24 to 60). Implant survival and mortality over time were estimated with the Kaplan-Meier method. Adverse events (measured with a modified Dindo-Clavien classification) and 90-day readmissions were additionally compared between groups.

RESULTS

In all, nine (8.01%) surgical failures were detected. All failures occurred within the first 24 months following surgery. The 24-month implant survival was 95.4% (95% confidence interval (CI) 89.13 to 100) for B1 fractures treated with internal fixation, 90% (95% CI 76.86 to 100) for B2 PFFs treated with osteosynthesis-only, and 85.8% (95% CI 74.24 to 97.36) for B2 fractures treated with revision THA, without significant differences between groups (p = 0.296). Readmissions and major adverse events including mortality were overall high, but similar between groups (p > 0.05). The two-year patient survival rate was 87.1% (95% CI 77.49 to 95.76), 66.7% (95% CI 48.86 to 84.53), and 84.2% (95% CI 72.63 to 95.76), for the B1 group, B2 osteosynthesis group, and B2 revision group, respectively (p = 0.102).

CONCLUSION

Implant survival in Vancouver B2 PFFs treated with internal fixation was similar to that of B1 fractures treated with the same method and to B2 PFFs treated with revision arthroplasty. Low-demand, elderly patients with B2 fractures around well-cemented polished femoral components with an intact bone-cement interface can be safely treated with internal fixation. Cite this article: Bone Joint J 2021;103-B(7):1222-1230.

Risk factors influencing fracture characteristics in postoperative periprosthetic femoral fractures around cemented stems in total hip arthroplasty : a multicentre observational cohort study on 584 fractures

Aims

This study evaluates risk factors influencing fracture characteristics for postoperative periprosthetic femoral fractures (PFFs) around cemented stems in total hip arthroplasty.

Methods

Data were collected for PFF patients admitted to eight UK centres between 25 May 2006 and 1 March 2020. Radiographs were assessed for Unified Classification System (UCS) grade and AO/OTA type. Statistical comparisons investigated relationships by age, gender, and stem fixation philosophy (polished taper-slip (PTS) vs composite beam (CB)). The effect of multiple variables was estimated using multinomial logistic regression to estimate odds ratios (ORs) with 95% confidence intervals (CIs). Surgical treatment (revision vs fixation) was compared by UCS grade and AO/OTA type.

Results

A total of 584 cases were included. Median age was 79.1 years (interquartile range 72.0 to 86.0), 312 (53.6%) patients were female, and 495 (85.1%) stems were PTS. The commonest UCS grade was type B1 (278, 47.6%). The most common AO/OTA type was spiral (352, 60.3%). Metaphyseal split fractures occurred only with PTS stems with an incidence of 10.1%. Male sex was associated with a five-fold reduction in odds of a type C fracture (OR 0.22 (95% CI 0.12 to 0.41); p < 0.001) compared to a type B fracture. CB stems were associated with significantly increased odds of transverse fracture (OR 9.51 (95% CI 3.72 to 24.34); p < 0.001) and wedge fracture (OR 3.72 (95% CI 1.16 to 11.95); p = 0.027) compared to PTS stems. Both UCS grade and AO/OTA type differed significantly (p < 0.001 and p = 0.001, respectively) between the revision and fixation groups but a similar proportion of B1 fractures underwent revision compared to fixation (45.3% vs 50.6%).

Conclusion

The commonest fracture types are B1 and spiral fractures. PTS stems are exclusively associated with metaphyseal split fractures, but their incidence is low. Males have lower odds of UCS grade C fractures compared to females. CB stems have higher odds of bending type fractures (transverse and wedge) compared to PTS stems. There is considerable variation in practice when treating B1 fractures around cemented stems.

Cite this article: Bone Jt Open 2021;2(7):466–475.