The February 2024 Oncology Roundup³⁶⁰ looks at: Does primary tumour resection improve survival for patients with sarcomas of the pelvis with metastasis at diagnosis?; Proximal femur replacements for an oncologic indication offer a durable endoprosthetic reconstruction option: a 40-year experience; The importance of awaiting biopsy results in solitary pathological proximal femoral fractures: do we need to biopsy solitary pathological fractures?; Effect of radiotherapy on local recurrence, distant metastasis, and overall survival in 1,200 extremity soft-tissue sarcoma patients; What to choose in bone tumour resections? Patient-specific instrumentation versus surgical navigation; Optimal timing of re-excision in synovial sarcoma patients: immediate intervention versus waiting for local recurrence; Survival differences of patients with resected extraskeletal osteosarcoma receiving two different (neo) adjuvant chemotherapy regimens; Solitary versus multiple bone metastases in the appendicular skeleton: should the surgical treatment be different?.

Aims

The aim of this study was to evaluate medium- to long-term outcomes and complications of the Stanmore Modular Individualised Lower Extremity System (SMILES) rotating hinge implant in revision total knee arthroplasty (rTKA) at a tertiary unit. It is hypothesized that this fully cemented construct leads to satisfactory clinical outcomes.

Abstract. Introduction. Patients presenting with loosening or a fracture between ipsilateral hip and knee replacements provide a unique reconstructive challenge. We present mid-term results of the cement-over megaprosthesis (COM) when managing these complex cases. A COM is cement-linked to the stem of a well-fixed existing implant. We report the largest series to date and show that this may be preferable to total femoral replacement in a cohort of patients who often have significant co-morbidities. Methodology. A retrospective analysis of patients undergoing COM between 2002–2022 was performed. Primary outcomes were defined as implant survival, displayed with survival analysis. Secondary outcomes included mortality and surgical complications. Functional outcomes included Visual Analogue Score (VAS), EuroQol-5D-3L and Musculoskeletal Tumour Society (MSTS) score at one year post operatively. Results. 34 patients underwent reconstructive cement-over technique. There were 20 custom distal femur replacements and 10 custom proximal femoral replacements. Two patients were revised, with a ten year implant survival of 94%. Fifteen patients died during the study period with an mean time to death of 66 months (25–109). The mean follow up was 75 months. 11 patients (32%) developed surgical complications. Mean VAS score was 4.9 (1–10), EuroQol-5D-3L index 0.45 (−0.59 – 0.88) and MSTS score was 16.8 (2–27) in 29 patients. Conclusion. The COM technique provides good implant survivorship in complex cases with compromised bone stock and this series confirms this as an established alternative to total femoral replacement in these cases

This edition of Cochrane Corner looks at some of the work published by the Cochrane Collaboration, covering interventions for treating distal femur fractures in adults; ultrasound and shockwave therapy for acute fractures in adults; and local corticosteroid injection versus placebo for carpal tunnel syndrome.

The management of periprosthetic distal femur fractures is an issue of increasing importance for orthopaedic surgeons. Because of the expanding indications for total knee arthroplasty (TKA) and an aging population with increasingly active lifestyles there has been a corresponding increase in the prevalence of these injuries. The management of these fractures is often complex because of issues with obtaining fixation around implants and dealing with osteopenic bone or compromised bone stock. In addition, these injuries frequently occur in frail, elderly patients, and the early restoration of function and ambulation is critical in these patients. There remains substantial controversy with respect to the optimal treatment of periprosthetic distal femur fractures, with some advocating for Locked Plating (LP), others Retrograde Intramedullary Nailing (RIMN) and finally those who advocate for Distal Femoral Replacement (DFR). The literature comparing these treatments, has been infrequent, and commonly restricted to single-center studies. The purpose of this study was to retrospectively evaluate a large series of operatively treated periprosthetic distal femur fractures from multiple centers and compare treatment strategies. Patients who were treated operatively for a periprosthetic distal femur fracture at 8 centers across North America between 2003 and 2018 were retrospectively identified. Baseline characteristics, surgical details and post-operative clinical outcomes were collected from patients meeting inclusion criteria. Inclusion criteria were patients aged 18 and older, any displaced operatively treated periprosthetic femur fracture and documented 1 year follow-up. Patients with other major lower extremity trauma or ipsilateral total hip replacement were excluded. Patients were divided into 3 groups depending on the type of fixation received: Locked Plating, Retrograde Intramedullary Nailing and Distal Femoral Replacement. Documented clinical follow-up was reviewed at 2 weeks, 3 months, 6 months and 1 year following surgery. Outcome and covariate measures were assessed using basic descriptive statistics. Categorical variables, including the rate of re-operation, were compared across the three treatment groups using Fisher Exact Test. In total, 121 patients (male: 21% / female: 79%) from 8 centers were included in our analysis. Sixty-seven patients were treated with Locked Plating, 15 with Retrograde Intramedullary Nailing, and 39 were treated with Distal Femoral Replacement. At 1 year, 64% of LP patients showed radiographic union compared to 77% in the RIMN group (p=0.747). Between the 3 groups, we did not find any significant differences in ambulation, return to work and complication rates at 6 months and 1 year (Table 1). Reoperation rates at 1 year were 27% in the LP group (17 reoperations), 16% in the DFR group (6 reoperations) and 0% in the RIMN group. These differences were not statistically significant (p=0.058). We evaluated a large multicenter series of operatively treated periprosthetic distal femur fractures in this study. We did not find any statistically significant differences at 1 year between treatment groups in this study. There was a trend towards a lower rate of reoperation in the Retrograde Intramedullary Nailing group that should be evaluated further with prospective studies. For any figures or tables, please contact the authors directly

Abstract. Introduction. We aimed to compare the outcomes of elderly patients with periarticular distal femur or supracondylar periprosthetic fractures treated with either open reduction internal fixation or distal femoral replacement. Methods. A retrospective review of patients over 65 years with AO Type B and C fractures of the distal femur or Su type I and II periprosthetic fractures treated with either a DFR or ORIF was undertaken. Outcomes including Length of Stay, PROMs (Oxford Knee Score and EQ 5D), infection, union, mortality, complication and reoperation rates were assessed. Data on confounding variables were also collected for multivariate analysis. Patients below 65 years and extra articular fractures were excluded. Results. 23 patients (11 in DFR group and 12 in ORIF group) fulfilled inclusion criteria and were included in the analysis. There was no difference between the DFR and ORIF groups with respect to SDI, demographic variables, ASA grade, FCI, preoperative Hb and renal function. There was no difference in 30 day mortality, reoperation rates, 30 day readmission rates and LOS between the two groups. Mean follow up was 12.7 and 15.9 months respectively in the DFR and ORIF groups. At final follow up after accounting for all confounding variables on multivariate analysis, functional outcomes using OKS (adjusted mean: 29.5 vs 15.8) and Health related Quality of Life outcomes using EQ 5D (adjusted mean: 0.453 vs −0.07) were significantly better in the DFR group. Conclusion. DFR for periarticular and periprosthetic distal femoral fractures in the elderly are associated with better patient reported outcomes

Aim. Repeat revision surgery of total hip or knee replacement may lead to massive bone loss of the femur. If these defects exceed a critical amount a stable fixation of a proximal or distal femur replacement may not be possible. In these extraordinary cases a total femur replacement (TFR) may be used as an option for limb salvage. In this retrospective study we examined complications, revision free survival (RFS), amputation free survival (AFS) and risk factors for decreased RFS and AFS following a TRF in cases of revision arthroplasty with a special focus on periprosthetic joint infection (PJI). Method. We included all implantations of a TFR in revision surgery from 2006–2018. Patients with a primary implantation of a TFR for oncological indications were not included. Complications were classified using the Henderson Classification. Primary endpoints were revision of the TFR or disarticulation of the hip. The minimum follow up was 24 month. RFS and AFS were analyzed using Kaplan-Meier method, patients´ medical history was analyzed for possible risk factors for decreased RFS and AFS. Results. After applying the inclusion criteria 58 cases of a TFR in revision surgery were included with a median follow-up of 48.5 month. The median age at surgery was 68 years and the median amount of prior surgeries was 3. A soft tissue failure (Henderson Type I) appeared in 16 cases (28%) of which 13 (22%) needed revision surgery. A PJI of the TFR (Henderson Type IV) appeared in 32 cases (55%) resulting in 18 (31%) removals of the TFR and implantation of a total femur spacer. Disarticulation of the hip following a therapy resistant PJI was performed in 17 cases (29%). The overall 2-year RFS was 36% (95% confidence interval(CI) 24–48%). Patients with a Body mass Index (BMI) >30kg/m² had a decreased RFS after 24 month (>30kg/m² 11% (95%CI 0–25%) vs. <30kg/m² 50% (95%CI 34–66%)p<0.01). The overall AFS after 5 years was 68% (95%CI 54–83%). A PJI of the TFR and a BMI >30kg/m² was significantly correlated with a lower 5-year AFS (PJI 46% (95%CI 27–66%) vs no PJI 100%p<0.001) (BMI >30kg/m² 30% (95% KI 3–57%) vs. <30km/m² 85% (95% KI 73–98%)p<0.01). Conclusions. A TFR in revision arthroplasty is a valuable option for limb salvage but complications in need of further revision surgery are common. Patients with a BMI >30kg/m² should be informed regarding the increased risk for revision surgery and loss of extremity before operation

Abstract. Introduction. Distal Femoral Fractures around a Total Knee Replacement have a reported incidence of 0.25–2.3% of primary TKRs. Literature suggests that these fractures have high complication rates such as non union and revision. Methodology. A retrospective case note review was undertaken of all patients who sustained a distal femoral fracture around a TKR from April 2014-April 2021. Data parameters collected included patient demographics, classification of fracture, management, post op mobility, fracture union and mortality. Results. 52 distal femoral fractures were recorded, out of which 5 patients had bilateral fractures. The average age was 83.6 years (61–101). 41 fractures were managed operatively with 61% undergoing ORIF, 37% undergoing Distal Femoral Replacement & 2% undergoing a retrograde IM Nail. The median LOS was 22 days (11–85) for patients treated with DFR versus 10 (3–75) for those undergoing an ORIF. 60% of DFR patients were discharged home compared to 56% of those who underwent an ORIF. All the DFR patients were FWB post op compared to ORIF 24%. Conclusion. Over a 7 year study period, 52 distal femoral fractures were reviewed. Despite FWB status post op, patients undergoing a DFR had a longer length of stay and less were discharged home compared to the ORIF group. Given the cost of a distal femoral replacement (£4485-6500) compared to £212-297 for a locking plate, in order to get patients FWB post operatively potentially dual plating (medial and lateral) may need to be considered if the fracture is amenable to improve stability & allow FWB

Abstract. Background. The incidence of periprosthetic fractures of the femur around a total knee arthroplasty (TKA) is rising and this is owed to the increased longevity that today's TKA implants allow for, as well as an aging population. These injuries are significant as they are related to increased morbidity and mortality. Methods. We retrospectively reviewed all periprosthetic fractures around a TKA that presented to our NHS Trust between 2011 to 2020. Medical records were reviewed. Treatment, complications and mortality were noted. Results. 37 patients (34 females) with an average age of 84 (range 65–99) met the inclusion criteria for this study. 17 patients (45.9%) underwent open reduction and internal fixation (ORIF), eight patients (21.6%) underwent revision arthroplasty to a distal femoral replacement (DFR) and 12 patients (32.4%) were treated non-operatively. 10 (58.8%) of the 17 patients that were treated with ORIF were discharged from hospital to a rehabilitation facility rather than their usual residence. In comparison, 3 (37.5%) of the patients that were treated with a DFR were discharged to a rehabilitation facility. one-year mortality rate in the ORIF group was 29.4 compared to 12.5% in those that had a DFR. Conclusion. Revision arthroplasty using a DFR should be considered in patients with periprosthetic fractures around a TKR, as it is associated with lower mortality rates and higher immediate post-operative function

Aims

Rotating-hinge knee prostheses are commonly used to reconstruct the distal femur after resection of a tumour, despite the projected long-term burden of reoperation due to complications. Few studies have examined the factors that influence their failure and none, to our knowledge, have used competing risk models to do so. The purpose of this study was to determine the risk factors for failure of a rotating-hinge knee distal femoral arthroplasty using the Fine-Gray competing risk model.

Aims

Porous metaphyseal cones can be used for fixation in revision total knee arthroplasty (rTKA) and complex TKAs. This metaphyseal fixation has led to some surgeons using shorter cemented stems instead of diaphyseal engaging cementless stems with a potential benefit of ease of obtaining proper alignment without being beholden to the diaphysis. The purpose of this study was to evaluate short term clinical and radiographic outcomes of a series of TKA cases performed using 3D-printed metaphyseal cones.

Debate surrounds the optimum operative treatment of periprosthetic distal femoral fractures (PDFFs) at the level of well fixed femoral components; lateral locking plate fixation (LLP-ORIF) or distal femoral replacement (DFR). To determine which attributed the least peri-operative morbidity and mortality we performed a retrospective cohort study of 60 consecutive unilateral PDFFs of Su types II (40/60) and III (20/60) in patients ≥60 years; 33 underwent LLP-ORIF and 27 underwent DFR. The primary outcome measure was reoperation. Secondary outcomes included perioperative complications and functional mobility status. Kaplan Meier survival analysis was performed. Cox multivariable regression analysis identified risk factors for reoperation after LLP-ORIF. Mean length of follow-up was 3.8 years (range 1.0–10.4). One-year mortality was 13% (8/60). Reoperation rate was significantly higher following LLP-ORIF: 7/33 vs 0/27, p=0.008. For the endpoint reoperation, five-year survival was better following DFR: 100% compared to 70.8% (51.8 to 89.8 95%CI) (p=0.006). For the endpoint mechanical failure (including radiographic loosening) there was no difference at 5 years: ORIF 74.5% (56.3 to 92.7); DFR 78.2% (52.3 to 100), p=0.182). Reoperation following LLP-ORIF was independently associated with medial comminution: HR 10.7 (1.45 to 79.5, p=0.020). Anatomic reduction was protective against reoperation: HR 0.11(0.013 to 0.96, p=0.046). When inadequately fixed fractures were excluded differences in survival were no longer significant: reoperation (p=0.156); mechanical failure (p=0.453). Reoperation rates are higher following LLP-ORIF of low PDFFs compared to DFR. Where adequate reduction, proximal fixation and augmentation of medial comminution is used there is no difference in survival between LLP-ORIF and DFR

Aims

We have evaluated the survivorship, outcomes, and failures of an interlocking, reconstruction-mode stem-sideplate implant used to preserve the native hip joint and achieve proximal fixation when there is little residual femur during large endoprosthetic reconstruction of the distal femur.

Introduction. 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 (IPFF). Our study aimed to assess treatment methodologies, implant survivorship, and clinical outcomes of patients with IPFF. Methods. 77 patients treated for an IPFF from 1985–2017 at a single large referral center were reviewed. Prior to the fracture, at the hip/knee sites respectively 46 femurs had primary/primary, 21 had revision/primary, 3 had primary/revision and 7 had revision/revision components. Mean age and BMI were 74 years and 30 kg/m. 2. , respectively. Mean follow-up after fracture treatment was 7 years. Results. Sixty fractures were classified as Vancouver C (UCS D) while 17 were Vancouver B (UCS B). Fifty-seven patients (74%) were treated with ORIF; 3 developed a non-union, 3 developed a PJI, and 2 developed aseptic loosening. Nineteen patients (25%) were treated with revision arthroplasty including: 13 revision THAs, 4 distal femoral replacements, 1 revision TKA, and 1 total femoral replacement of which 2 developed aseptic loosening and 2 developed a non-union. Survivorship free from any reoperation for the entire cohort was 79% at 2 years. Patients in the ORIF group who went on to union tended to have stemmed components and greater interprosthetic distance (IPD=189mm vs. 163mm, p=0.55) than non-united fractures. Patients who went on to nonunion in the revision arthroplasty group had higher medullary diameter: cortical width ratio (2.5 vs. 1.3, p=0.01) and lower IPD (36mm vs. 202mm, p=0.002). 95% of patients were ambulatory at latest follow-up. Conclusion. Interprosthetic femur fractures are technically and biologically challenging cases. An individualized approach of internal fixation versus revision arthroplasty led to a 79% success rate free of reoperation at 2 years with 95% of patients ambulatory. Continued improvements in management are warranted

Over the last decade, the number of total knee arthroplasty (TKA) has risen over 125%. Numerous studies have established a relationship between obesity and complications in primary TKA. Interestingly, few studies have investigated medical and orthopaedic complications in obese patients undergoing revision TKA (RTKA). With the increasing number of RTKA and with the prevalence of obesity still on the rise, the study of obesity on complications following RTKA is indicated. We retrospectively reviewed 180 RTKA performed by a single surgeon done between August 2008 and June 2017. All patients who underwent RTKA were included, but revisions done with simultaneous extensor mechanism reconstruction and/or distal femur replacement were excluded since these procedures are technically more demanding. 154 revisions met our inclusion/exclusion criteriaes and were included in the final analysis. 81 patients were included in the non-obese group (BMI . The total number of orthopaedic complications in the obese group (46.6%) was significantly higher than in the non-obese group (27.2%) (OR=1.71) (p = 0.01). The number of infection was higher in the obese group (11%) than in the non-obese (6.2%) but this was not statistically significant (OR=1.77) (p = 0.28). Reoperation rate was also higher in the obese group (23.3%) than in the non-obese group (16%) but this did not reach statistical significance (OR=1.46) (p = 0.26) (Table 3). Medical complications were higher in the obese group (31.5% vs 19.8%) (OR=1.59) (p=0.09). According to the Dindo-Clavien classification, the obese group demonstrated a significantly higher rate of grade 3 or higher complications (p = 0.01). Obesity significantly increases the occurrence of orthopaedic complications following RTKA. Obesity also seems to increase the number of medical complications following RTKA. The obese patient should be informed prior to revision TKA that there is an increased risk of complications when compared with the non-obese patient. Further research with higher power would seem advisable to confirm this trend. For any figures or tables, please contact the authors directly

Aims

Limb salvage in bone tumour patients replaces the bone with massive segmental prostheses where achieving bone integration at the shoulder of the implant through extracortical bone growth has been shown to prevent loosening. This study investigates the effect of multidrug chemotherapy on extracortical bone growth and early radiological signs of aseptic loosening in patients with massive distal femoral prostheses.

Aims

Our objective is to describe our early and mid-term results with the use of a new simple primary knee prosthesis as an articulating spacer in planned two-stage management for infected knee arthroplasty. As a second objective, we compared outcomes between the group with a retained first stage and those with a complete two-stage revision.