Aims. Femoral cement-in-cement revision is a well described technique to reduce morbidity and complications in hip revision surgery. Traditional techniques for septic revision of hip arthroplasty necessitate removal of all bone cement from the femur. In our two centres, we have been using a cement-in-cement technique, leaving the distal femoral bone cement in selected patients for septic hip revision surgery, both for single and the first of two-stage revision procedures. A prerequisite for adoption of this technique is that the surgeon considers the cement mantle to be intimately fixed to bone without an intervening membrane between cement and host bone. We aim to report our experience for this technique. Methods. We have analyzed patients undergoing this cement-in-cement technique for femoral revision in infection, and present a consecutive series of 89 patients. Follow-up was undertaken at a mean of 56.5 months (24.0 to 134.7) for the surviving cases. Results. Seven patients (7.9%) required further revision for infection. Ten patients died of causes unrelated to their infection before their two-year review (mean 5.9 months; 0.9 to 18.6). One patient was lost to follow-up at five months after surgery, and two patients died of causes unrelated to their hip shortly after their two-year review was due without attending. Of the remaining patients, 69 remained infection-free at final review. Radiological review confirms the mechanical success of the procedure as previously described in aseptic revision, and postoperative Oxford Hip Scores suggest satisfactory functional outcomes. Conclusion. In conclusion, we found that retaining a well-fixed femoral cement mantle in the presence of infection and undertaking a cement-in-cement revision was successful in 82 of the patients (92.1%) in our series of 89, both in terms of eradication of infection and component fixation. These results are comparable to other more invasive techniques and offer significant potential benefits to the patient. Cite this article: Bone Joint J 2022;104-B(2):212–220

Intro. Calcium sulphate (CS) is a recent alternative for antibiotic elution in infected bones and joints. The purpose of this study is to evaluate the use of antibiotic impregnated calcium sulphate (AICS) beads in the management of infected tibia and femur, with regards to patient outcomes and complication rates (including reinfection rate, remission rate and union rate). Methods. Searches of AMED, CINAHL, EMBASE, EMCARE, Medline, PubMed and Google Scholar were conducted in June 2020, with the mesh terms: “Calcium sulphate beads” or “Calcium sulfate beads” or “antibiotic beads” or “Stimulan” AND “Bone infection” or “Osteomyelitis” or “Debridement” AND “Tibia” or “Femur”. Risk of bias was assessed using the Risk of Bias in Non-randomised Studies of interventions (ROBINS-i) tool, and quality assessed via the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) criteria. Results. Out of 105 relevant papers, 11 met the inclusion criteria for data extraction. Total infection recurrence rate was 6.8% (range 3.2 – 11.9%, n = 295), which was significantly lower (p < 0.001) than that of polymethylmethacrylate (PMMA; 19.6%, n = 163). Complication rates varied. The main issue regarding AICS use was wound drainage (7.9 – 33.3%), which was considerably higher in studies involving treatment of the tibia only. Studies using PMMA did not experience this issue, but there were a few incidences of superficial pin tract infection following surgery. Conclusions. AICS was consistently effective at infection eradication, despite variation in causative organism and location of bead placement. Additionally, PMMA has many inconvenient properties. AICS is therefore an attractive alternative as an adjunct in treatment of infected tibia and femur. Wound drainage rate varied and was higher in studies regarding tibial cases alone

Aims. Fractures of the distal femur are an important cause of morbidity. Their optimal management remains controversial. Contemporary implants include angular-stable anatomical locking plates and locked intramedullary nails (IMNs). We compared the long-term patient-reported functional outcome of fixation of fractures of the distal femur using these two methods of treatment. Patients and Methods. A total of 297 patients were retrospectively identified from a State-wide trauma registry in Australia: 195 had been treated with a locking plate and 102 with an IMN. Baseline characteristics of the patients and their fractures were recorded. Health-related quality-of-life, functional and radiographic outcomes were compared using mixed effects regression models at six months and one year. Results. There was a clinically relevant and significant difference in quality-of-life at six months in favour of fixation with an IMN (mean difference in EuroQol-5 Dimensions Score (EQ-5D) = 0.12; 95% CI 0.02 to 0.22; p = 0.025). There was weak evidence that this trend continued to one year (mean difference EQ-5D = 0.09; 95% CI -0.01 to 0.19; p = 0.073). There was a significant although very small reduction in angular deformity using an IMN (mean difference -1.02; 95% CI -1.99 to -0.06; p = 0.073). There was no evidence that there was a difference in any other outcomes at any time point. Take home message: IMN may be a superior treatment compared with anatomical locking plates for fractures of the distal femur. These findings are concordant with other data from pilot randomised studies which favour treatment of these fractures with an IMN. This study strongly supports the need for a definitive randomised trial. Cite this article: Bone Joint J 2016;98-B:846–50

The aim of this study was to investigate the relationship between the geometry of the proximal femur and the incidence of intra-operative fracture during uncemented total hip arthroplasty (THA). We studied the pre-operative CT scans of 100 patients undergoing THA with an uncemented femoral component. We measured the anteroposterior and mediolateral dimensions at the level of division of the femoral neck to calculate the aspect ratio of the femur. Wide variations in the shape of the femur were observed, from round, to very narrow elliptic. The femurs of women were narrower than those of men (p < 0.0001) and small femurs were also narrower than large ones. Patients with an intra-operative fracture of the calcar had smaller and narrower femurs than those without a fracture (p < 0.05) and the implanted Corail stems were smaller in those with a fracture (mean size 9 vs 12, p < 0.0001). The variability of the shape of the femoral neck at the level of division contributes to the understanding of the causation of intra-operative fractures in uncemented THA. Cite this article: Bone Joint J 2015;97-B:741–8

Aims. After intercalary resection of a bone tumour from the femur, reconstruction with a vascularized fibular graft (VFG) and massive allograft is considered a reliable method of treatment. However, little is known about the long-term outcome of this procedure. The aims of this study were to determine whether the morbidity of this procedure was comparable to that of other reconstructive techniques, if it was possible to achieve a satisfactory functional result, and whether biological reconstruction with a VFG and massive allograft could achieve a durable, long-lasting reconstruction. Patients and Methods. A total of 23 patients with a mean age of 16 years (five to 40) who had undergone resection of an intercalary bone tumour of the femur and reconstruction with a VFG and allograft were reviewed clinically and radiologically. The mean follow-up was 141 months (24 to 313). The mean length of the fibular graft was 18 cm (12 to 29). Full weight-bearing without a brace was allowed after a mean of 13 months (seven to 26). Results. At final follow-up, the mean Musculoskeletal Tumor Society Score of 22 evaluable patients was 94% (73 to 100). Eight major complications, five fractures (21.7%), and three nonunions (13%) were seen in seven patients (30.4%). Revision-free survival was 72.3% at five, ten, and 15 years, with fracture and nonunion needing surgery as failure endpoints. Overall survival, with removal of allograft or amputation as failure endpoints, was 94.4% at five, ten, and 15 years. Discussion. There were no complications needing surgical revision after five years had elapsed from surgery, suggesting that the mechanical strength of the implant improves with time, thereby decreasing the risk of complications. In young patients with an intercalary bone tumour of the femur, combining a VFG and massive allograft may result in a reconstruction that lasts a lifetime. Cite this article: Bone Joint J 2018;100-B:378–86

This is a retrospective study of survivors of recent conflicts with an open fracture of the femur. We analysed the records of 48 patients (48 fractures) and assessed the outcome. The median follow up for 47 patients (98%) was 37 months (interquartile range 19 to 53); 31 (66%) achieved union; 16 (34%) had a revision procedure, two of which were transfemoral amputation (4%). The New Injury Severity Score, the method of fixation, infection and the requirement for soft-tissue cover were not associated with a poor outcome. The degree of bone loss was strongly associated with a poor outcome (p = 0.00204). A total of four patients developed an infection; two with S. aureus, one with E. coli and one with A. baumannii. This study shows that, compared with historical experience, outcomes after open fractures of the femur sustained on the battlefield are good, with no mortality and low rates of infection and late amputation. The degree of bone loss is closely associated with a poor outcome. Cite this article: Bone Joint J 2015;97-B:842–6

Introduction: Increasing number of osteoporotic fractures of the femur, especially upper part of the femur creates everyday problem of health services. Treatment of these fractures has been improving markedly during the past 25 years. DHS, gamma nail and some other implants are very useful in everyday surgery. However some of complications still can not be resolved like cut out. Osteoporotic fractures in subtrochanteric area represent even bigger challenging. Diaphyseal fractures are also difficult to be treated. The main problem is quality of osteoporotic bone. Plate with parallel screws doesn’t provide reliable fixation. Intramedulary nails, because of wide channel in distal femur area also don’t provide desirable fixation stability. Material and Method: We analysed results of using of one new device: selfdynamisable internal fixator (SIF) in the series of 389 patients treated because of upper femur fractures. That device has possibilities of spontaneous dynamisation in two axes: along the femoral neck axis and along the diaphyseal axis. Spontaneous dynamisation in the diaphyseal axis is very important if diaphyseal or subrtochanteric fracture or comminuted fracture of the upper femur with subtrochanteric extension treated. For activation of axial dynamisation it not necessary to do any action from outside the body. This feature is activated spontaneously if there is no progress in fracture union within 6–8 weeks. This device provides three-dimensional fixation using clams and rod onto the lateral surface of the femur. The age of patients was from 59 to 87 years. This internal fixator is applied using minimally invasive method – by one or two small incisions. Results: During the treatment it has been confirmed working of self-dynamisation concept. Spontaneous dynamisation in the long axis of the femur has been proven in 21% of patients with subtrochanteric and diaphyseal fractures and it has been proven radiologically that sliding happened between 1–4 mm (average 2.5 mm). Such dynamisation together with 3D configuration of screws resulted in relatively quick fracture healing. Follow up was 19 months (6–60). Altogether 97.6% fractures healed within normal healing time. There were 1 infection, 2 cut out, 1 mechanical complication, 4 delay unions and one non-union. Conclusion: According to results obtained, it can bee concluded that new biological internal fixator is suitable for minimally invasive technique, without opening of fracture site

We investigated the clinical outcome of internal fixation for pathological fracture of the femur after primary excision of a soft-tissue sarcoma that had been treated with adjuvant radiotherapy. A review of our database identified 22 radiation-induced fractures of the femur in 22 patients (seven men, 15 women). We noted the mechanism of injury, fracture pattern and any complications after internal fixation, including nonunion, hardware failure, secondary fracture or deep infection. The mean age of the patients at primary excision of the tumour was 58.3 years (39 to 86). The mean time from primary excision to fracture was 73.2 months (2 to 195). The mean follow-up after fracture fixation was 65.9 months (12 to 205). Complications occurred in 19 patients (86%). Nonunion developed in 18 patients (82%), of whom 11 had a radiological nonunion at 12 months, five a nonunion and hardware failure and two an infected nonunion. One patient developed a second radiation-associated fracture of the femur after internal fixation and union of the initial fracture. A total of 13 patients (59%) underwent 24 revision operations. Internal fixation of a pathological fracture of the femur after radiotherapy for a soft-tissue sarcoma has an extremely high rate of complication and requires specialist attention. Cite this article: Bone Joint J 2013;95-B:1144–8

It is becoming increasingly common for a patient to have ipsilateral hip and knee replacements. The inter-prosthetic (IP) distance, the distance between the tips of hip and knee prostheses, has been thought to be associated with an increased risk of IP fracture. Small gap distances are generally assumed to act as stress risers, although there is no real biomechanical evidence to support this. The purpose of this study was to evaluate the influence of IP distance, cortical thickness and bone mineral density on the likelihood of an IP femoral fracture. A total of 18 human femur specimens were randomised into three groups by bone density and cortical thickness. For each group, a defined IP distance of 35 mm, 80 mm or 160 mm was created by choosing the appropriate lengths of component. The maximum fracture strength was determined using a four-point bending test. The fracture force of all three groups was similar (p = 0.498). There was a highly significant correlation between the cortical area and the fracture strength (r = 0.804, p <  0.001), whereas bone density showed no influence. This study suggests that the IP distance has little influence on fracture strength in IP femoral fractures: the thickness of the cortex seems to be the decisive factor. Cite this article: Bone Joint J 2014;96-B:1378–84

We retrospectively reviewed 101 consecutive patients with 114 femoral tumours treated by massive bone allograft at our institution between 1986 and 2005. There were 49 females and 52 males with a mean age of 20 years (4 to 74). At a median follow-up of 9.3 years (2 to 19.8), 36 reconstructions (31.5%) had failed. The allograft itself failed in 27 reconstructions (24%).

Mechanical complications such as delayed union, fracture and failure of fixation were studied. The most adverse factor on the outcome was the use of intramedullary nails, followed by post-operative chemotherapy, resection length > 17 cm and age > 18 years at the time of intervention. The simultaneous use of a vascularised fibular graft to protect the allograft from mechanical complications improved the outcome, but the use of intramedullary cementing was not as successful.

In order to improve the strength of the reconstruction and to advance the biology of host–graft integration, we suggest avoiding the use of intramedullary nails and titanium plates, but instead using stainless steel plates, as these gave better results. The use of a supplementary vascularised fibular graft should be strongly considered in adult patients with resection > 17 cm and in those who require post-operative chemotherapy.

There is a strong association between the presence of a calcar collar on a cementless stem and a reduced risk of revision surgery for periprosthetic fracture of the femur (PFF). A medial calcar collar may act to reduce relative movement between the implant and femur during PFF, through calcar-collar contact (CCC). The aims were:. Estimate the effect of CCC on periprosthetic fracture mechanics. Estimate the effect of initial calcar-collar separation on the likelihood of CCC. Three groups of six composite femurs were implanted with a fully coated collared cementless femoral stem. Neck resection differed between groups (group 1 = no additional resection, group 2 = 3mm additional resection, group 3 = 6mm additional resection). PFF were simulated using a previously published technique. Fracture torque and rotational displacement were measured and torsional stiffness and rotational work prior to fracture were estimated. Results between trials where CCC did and did not occur where compared using Mann-Whitney U tests. Logistic regression estimated the odds (OR) of failing with 95% confidence interval (CI) to achieve CCC for a given initial separation. Where CCC occurred fracture torque was greater (47.33 [41.03 to 50.45] Nm versus 38.26 [33.70 to 43.60] Nm, p= 0.05) and torsional stiffness was greater (151.38 [123.04 to 160.42] rad.Nm. −1. versus 96.86 [84.65 to 112.98] rad.Nm. −1. , p <0.01). CCC was occurred in all cases in group one, 50% in group two and 0% in group three. OR of failure to obtain CCC increased 3.8 fold (95% CI 1.6 to 30.2, p <0.05) for each millimetre of separation. Resistance to fracture and construct stiffness increased when a the collar made contact with the calcar prior to fracture and the chances of contact decrease with increasing initial separation at the time of implantation. Surgeons should aim to achieve a calcar-collar distance of less than 1mm following implantation to ensure CCC and to reduce the risk of fracture

Abstract. Objective. To estimate the effect of calcar collar contact on periprosthetic fracture mechanics using a collared fully coated cementless femoral stem. Methods. Three groups of six composite femurs were implanted with a fully coated collared cementless femoral stem. Neck resection was increased between groups (group 1 = normal, group 2 = 3mm additional, group 3 = 6mm additional), to simulate failure to obtain calcar collar contact. Periprosthetic fractures of the femur were simulated using a previously published technique. Fracture torque and rotational displacement were measured and torsional stiffness and rotational work prior to fracture were estimated. High speed video recording identified if collar to calcar contact (CCC) occurred. Results between trials where calcar contact did and did not occur where compared using Mann-Whitney U tests. Results. Where CCC occurred versus where no CCC occurred, fracture torque was greater (47.33 [41.03 to 50.45] Nm versus 38.26 [33.70 to 43.60] Nm, p= 0.05), Rotational displacement was less (0.29 [0.27 to 0.39] rad versus 0.37 [0.33 to 0.49] rad, p= 0.07), torsional stiffness was greater (151.38 [123.04 to 160.42] rad. Nm-1 versus 96.86 [84.65 to 112.98] rad.Nm-1, p <0.01) and rotational work was similar (5.88 [4.67, 6.90] J versus 5.31 [4.40, 6.56] J, p= 0.6). Conclusions. Resistance to fracture and construct stiffness increased when a collared cementless stem made contact with the femoral calcar prior to fracture. These results demonstrate that calcar-collar contact and not a calcar collar per se, is crucial to maximising the protective effect of a medial calcar collar on the risk of post-operative periprosthetic fractures of the femur. Declaration of Interest. (a) fully declare any financial or other potential conflict of interest

Introduction. The human body is a complex and continually adapting organism. It is theorised that the morphology of the proximal femur is closely related to that of the distal femur. Patients that have abnormal anatomy in the proximal femur, such as a high femoral neck anteversion angle, may have abnormal anatomy in the distal femur to overcome proximal differences. This phenomenon is of key interest when performing Total Hip Replacement (THR) or Total Knee Replacement (TKR) surgery. The current design and placement of existing hip and knee implants does not account for any correlation between the anatomical parameters of the proximal and distal femur, where bone anatomy may have adapted to compromise for abnormalities. A preliminary study of 21 patients has been carried out to assess the relationship between the proximal and distal femur. The difficulties in defining and measuring key anatomical parameters on the femur have been widely discussed in the literature [1] due to its complex three dimensional geometry. Using CT scans of healthy octogenarians, it was possible to mark key anatomical landmarks which could be used to define various anatomical axes throughout the femur. Correlation analyses could then be carried out on these parameters to assess the relationship between proximal and distal femur morphology. Methods. Each femur was initially realigned along the mechanical axis (MA); defined by joining the centre of the femoral head (FHC) to the centre of the intercondylar notch (INC) [2]. All anatomical landmarks were then identified using the Materialise Mimics v12 software (Figure 1 and 2) and exported into Microsoft Excel for analysis. Key anatomical parameters which were derived from these landmarks included the femoral neck axis (FNA), femoral neck anteversion angle (FNAA) [1–4], condylar twist angle, clinical transepicondylar axis (TEA), trochlea sulcus angle and medial and lateral trochlea twist. A correlation analysis was carried out on SPSS Statistics v20 (IBM) to assess the relationship between proximal and distal anatomical parameters. Results. The correlation analysis displayed a positive linear correlation between the FNAA and the clinical TEA (adjusted R squared = 0.471, p < 0.001) indicating that an abnormally high FNAA is correlated with a higher TEA angle (Figure 3). No strong relationship was found between the FNAA and the additional distal parameters compared, in particular there was no trend between the FNAA and the geometry of the trochlea as measured by the sulcus angle and trochlea twist. Discussion. The morphology of the distal femur seems to be at least partially correlated with the proximal femur and the relationship should be studied further to assess any potential effect on THA and TKA surgery. An extension of this study should assess an increased patient sample size and further anatomical parameters

Introduction. Infected big gap non-union of femur and tibia are difficult to treatment because of infection, bone loss, shortening, poor sift tissue over and deformity. Step by step management and definitive treatment by Ilizarov fixator was achieved in our cases. Materials and Methods. A long defect which is more than 10cm in femur and tibia because of infection and gap, tumor resection, traumatic loss, which is very difficult to treat by conventional method and that's why we treated that type defect by Tibialization of fibula with Ilizarov technique. Management of infected big gap non-union of the femur include debridement and bone transport by Ilizarov technique by using Ilizarov fixator we can correct deformities, regenerate new bone without bone grafting, correct LLD and patient can weight bear during the course of treatment. We retrospectively reviewed records of 246 consecutive patients who underwent distraction osteogenesis using Ilizarov compression-distraction device for infected big gap INU of femur and tibia from 2000 to 2020. Results. All healed with the application of Ilizarov fixator, 5 needed reapplications of Ilizarov to achieve 100% union. 210 were excellent, 25 good and 6 were fair by ASAMI criteria. Mean Ilizarov duration was 366 days (130–250). Mean 8.2 cm length was achieved in the regenerate. Conclusions. A well plan step by step Ilizarov technique to cover infected gap non-union of femur and tibia is an excellent method in challenging cases. Excellent results cannot be achieved with conventional methods but can be easily achieved with Ilizarov technique within 1–2 years

Aims. Osteoarticular reconstruction of the distal femur in childhood has the advantage of preserving the tibial physis. However, due to the small size of the distal femur, matching the host bone with an osteoarticular allograft is challenging. In this study, we compared the outcomes and complications of a resurfaced allograft-prosthesis composite (rAPC) with those of an osteoarticular allograft to reconstruct the distal femur in children. Methods. A retrospective analysis of 33 skeletally immature children with a malignant tumour of the distal femur, who underwent resection and reconstruction with a rAPC (n = 15) or osteoarticular allograft (n = 18), was conducted. The median age of the patients was ten years (interquartile range (IQR) 9 to 11) in the osteoarticular allograft group and nine years (IQR 8 to 10) in the rAPC group (p = 0.781). The median follow-up of the patients was seven years (IQR 4 to 8) in the osteoarticular allograft group and six years (IQR 3 to 7) in the rAPC group (p = 0.483). Limb function was evaluated using the Musculoskeletal Tumor Society (MSTS) score. Results. At final follow-up, the knee was unstable in 9/18 patients (50%) in the osteoarticular allograft group and 2/15 patients (13%) in the rAPC group (p = 0.026). The median range of motion (ROM) of the knee was 117° (IQR 115° to 120°) in the osteoarticular allograft group and 100° (IQR 95° to 105°) in the rAPC group (p < 0.001). The median MSTS score was 25 (IQR 23 to 26) in the osteoarticular allograft group and 28 (IQR 26 to 29) in the rAPC group (p = 0.007). Osteoarthritic change was detected in 11/18 patients (61%) in the osteoarticular allograft group and in 4/15 (26%) patients in the rAPC group (p = 0.048). Conclusion. In our series, a resurfaced allograft-prosthesis composite provided better knee stability and function, with a lower rate of osteoarthritis; an osteoarticular allograft was associated with better knee ROM. Cite this article: Bone Joint J 2022;104-B(10):1174–1179

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

Introduction. Fully implantable systems are used commonly only after maturity. What are indications to use fully implantable systems at the femur even in children?. Materials and Methods. Implantable lengthening nails (FITBONE) were used retrograde at the femur in minimal invasive technique to correct a limb length discrepancy of >6 cm. In 5 cases a relevant deformity was corrected in the same surgery. In all cases a final step of lengthening was planned at the femur and at the tibia with fully implantable devices at maturity. Results. 18 patients with the medium age of 10,3 years (8–14) were treated. In 17 cases the goal of lengthening was achieved without any complication. In one case of proximal femoral deficiency lengthening had to be stopped because of increasing tendency of knee joint luxation. Bone formation occurred circular around the nail in all cases. Full load bearing was possible in the average after 2,2 days/mm. No technical problems occur. In one case induced deformity in the lateral plane was observed which was corrected at the final step. At the end of treatment functional and cosmetical result was perfect in all cases. Conclusions. Fully implantable motorized distraction nails are a favorable option for lengthening and deformity correction of the femur even for children older than 10 years to correct limb length discrepancy of more than 6 cm. The treatment has a low pain level, is comfortable and nearly no scars are visible

Aims. One-stage revision hip arthroplasty for periprosthetic joint infection (PJI) has several advantages; however, resection of the proximal femur might be necessary to achieve higher success rates. We investigated the risk factors for resection and re-revisions, and assessed complications and subsequent re-revisions. Methods. In this single-centre, case-control study, 57 patients who underwent one-stage revision arthroplasty for PJI of the hip and required resection of the proximal femur between 2009 and 2018 were identified. The control group consisted of 57 patients undergoing one-stage revision without bony resection. Logistic regression analysis was performed to identify any correlation with resection and the risk factors for re-revisions. Rates of all-causes re-revision, reinfection, and instability were compared between groups. Results. Patients who required resection of the proximal femur were found to have a higher all-cause re-revision rate (29.8% vs 10.5%; p = 0.018), largely due to reinfection (15.8% vs 0%; p = 0.003), and dislocation (8.8% vs 10.5%; p = 0.762), and showed higher rate of in-hospital wound haematoma requiring aspiration or evacuation (p = 0.013), and wound revision (p = 0.008). The use of of dual mobility components/constrained liner in the resection group was higher than that of controls (94.7% vs 36.8%; p < 0.001). The presence and removal of additional metal hardware (odds ratio (OR) = 7.2), a sinus tract (OR 4), ten years’ time interval between primary implantation and index infection (OR 3.3), and previous hip revision (OR 1.4) increased the risk of proximal femoral resection. A sinus tract (OR 9.2) and postoperative dislocation (OR 281.4) were associated with increased risk of subsequent re-revisions. Conclusion. Proximal femoral resection during one-stage revision hip arthroplasty for PJI may be required to reduce the risk of of recurrent or further infection. Patients with additional metalware needing removal or transcortical sinus tracts and chronic osteomyelitis are particularly at higher risk of needing proximal femoral excision. However, radical resection is associated with higher surgical complications and increased re-revision rates. The use of constrained acetabular liners and dual mobility components maintained an acceptable dislocation rate. These results, including identified risk factors, may aid in preoperative planning, patient consultation and consent, and intraoperative decision-making. Cite this article: Bone Joint J 2021;103-B(11):1678–1685

The most important outcome predictor of Legg-Calvé-Perthes disease (LCPD) is the shape of the healed femoral head. However, the deformity of the femoral head is currently evaluated by non-reproducible, categorical, and qualitative classifications. In this regard, recent advances in computer vision might provide the opportunity to automatically detect and delineate the outlines of bone in radiographic images for calculating a continuous measure of femoral head deformity. This study aimed to construct a pipeline for accurately detecting and delineating the proximal femur in radiographs of LCPD patients employing existing algorithms. To detect the proximal femur, the pretrained stateof-the-art object detection model, YOLOv5, was trained on 1580 manually annotated radiographs, validated on 338 radiographs, and tested on 338 radiographs. Additionally, 200 radiographs of shoulders and chests were added to the dataset to make the model more robust to false positives and increase generalizability. The convolutional neural network architecture, U-Net, was then employed to segment the detected proximal femur. The network was trained on 80 manually annotated radiographs using real-time data augmentation to increase the number of training images and enhance the generalizability of the segmentation model. The network was validated on 60 radiographs and tested on 60 radiographs. The object detection model achieved a mean Average Precision (mAP) of 0.998 using an Intersection over Union (IoU) threshold of 0.5, and a mAP of 0.712 over IoU thresholds of 0.5 to 0.95 on the test set. The segmentation model achieved an accuracy score of 0.912, a Dice Coefficient of 0.937, and a binary IoU score of 0.854 on the test set. The proposed fully automatic proximal femur detection and segmentation system provides a promising method for accurately detecting and delineating the proximal femoral bone contour in radiographic images, which is necessary for further image analysis

Aims. The epiphyseal approach to a chondroblastoma of the intercondylar notch of a child’s distal femur does not provide adequate exposure, thereby necessitating the removal of a substantial amount of unaffected bone to expose the lesion. In this study, we compared the functional outcomes, local recurrence, and surgical complications of treating a chondroblastoma of the distal femoral epiphysis by either an intercondylar or an epiphyseal approach. Methods. A total of 30 children with a chondroblastoma of the distal femur who had been treated by intraregional curettage and bone grafting were retrospectively reviewed. An intercondylar approach was used in 16 patients (group A) and an epiphyseal approach in 14 (group B). Limb function was assessed using the Musculoskeletal Tumor Society (MSTS) scoring system and Sailhan’s functional criteria. Results. At final follow-up, the mean MSTS score was 29.1 (SD 0.9) in group A and 26.7 (SD 1.5) in group B (p = 0.006). According to Sailhan’s criteria, the knee function was good and fair in 14 (87.5%) and two (12.5%) patients of group A, and eight (57.1%) and six (42.9%) patients of group B, respectively (p = 0.062). The lesion had recurred in one patient (6.2%) in group A and four patients (28.6%) in group B. Limb shortening > 1 cm was recorded in one patient (6.2%) from group A and six patients (42.8%) from group B. Joint degeneration was noted in one patient from group A and three patients from group B. Conclusion. An intercondylar approach to a chondroblastoma of the middle two-quarters of the distal femoral epiphysis results in better outcomes than a medial or lateral epiphyseal approach: specifically, better limb function, a lower rate of recurrence, and a lower rate of physeal damage and joint degeneration. Cite this article: Bone Joint J 2024;106-B(2):195–202

Aims. Giant cell tumours (GCTs) of the proximal femur are rare, and there is no consensus about the best method of filling the defect left by curettage. In this study, we compared the outcome of using a fibular strut allograft and bone cement to reconstruct the bone defect after extended curettage of a GCT of the proximal femur. Methods. In a retrospective study, we reviewed 26 patients with a GCT of the proximal femur in whom the bone defect had been filled with either a fibular strut allograft (n = 12) or bone cement (n = 14). Their demographic details and oncological and nononcological complications were retrieved from their medical records. Limb function was assessed using the Musculoskeletal Tumor Society (MSTS) score. Results. Mean follow-up was 116 months (SD 59.2; 48 to 240) for the fibular strut allograft group and 113 months (SD 43.7; 60 to 192) for the bone cement group (p = 0.391). The rate of recurrence was not significantly different between the two groups (25% vs 21.4%). The rate of nononcological complications was 16.7% in the strut allograft group and 42.8% in the bone cement group. Degenerative joint disease was the most frequent nononcological complication in the cement group. The mean MSTS score of the patients was 92.4% (SD 11.5%; 73.3% to 100.0%) in the fibular strut allograft group and 74.2% (SD 10.5%; 66.7% to 96.7%) in the bone cement group (p < 0.001). Conclusion. Given the similar rate of recurrence and a lower rate of nononcological complications, fibular strut grafting could be recommended as a method of reconstructing the bone defect left by curettage of a GCT of the proximal femur. Cite this article: Bone Joint J 2022;104-B(2):297–301

As part of the workup long length femur radiograph may be carried out pre-operatively in patients presenting with a proximal femur fracture in order to rule out distant metastasis in patients with a history of malignancy but also in some patients in whom a suspicion of possible distal abnormality is aroused by the configuration of the proximal fracture. Using our unit’s database we identified all patients (n=689) presenting with a proximal femoral fracture between Sept 2006 and August 2007 at the Norfolk and Norwich University hospital in Norwich. Of 689 patients, 92 patients (13.2%) had long length femur radiograph performed before surgery. Indications included history of cancer (39), subtrochantric fractures (14), spontaneous fracture without any fall(2), paget s disease(1), early onset osteoporosis(1) while no clear indication was available in 35 patients. Five patients (5.5%) were found to have some abnormality. Three of the 39 patients with a history of previous cancer were found to have a distal femur metastasis. Two of the 35 patients where a clear indication was not apparent had abnormal findings: one patient had a distal femur infarction and another was found to have a distal femoral malunion. In both cases long leg films did not influence choice of implant. Of the 39 patients with a previous history of cancer, 24 had short implants (hemi-arthroplasty, intramedullary device, DHS), 14 had long implants and one patient died before the operation. Long length femoral radiographs appear to be indicated in patients with a documented history of a cancer as it helps to decide whether to use a long or short implant. However in patients without a history of malignancy, long leg films were of no value in decision making even if the configuration of the fracture was suspicious

Gunshot-induced fractures of the proximal femur typically present with severe comminution and bone loss. These fractures may also be associated with local damage to soft tissue, neurovascular structures and injuries to abdominal organs. The aim was to evaluate the outcomes of civilian gunshot injuries to the proximal femur at a major trauma center in South Africa. A retrospective review of all patients who sustained gunshot-induced proximal femur fractures between January 2014 and December 2017 was performed. Patients with gunshot injuries involving the hip joint, neck of femur or pertrochanteric fractures were included. Patient demographics, clinical- treatment and outcome data were collected. Results are reported as appropriate given the distribution of continuous data or as frequencies and counts. Our study included 78 patients who sustained 79 gunshot-induced proximal femur fractures. The mean age of patients was 31 ± 112, and the majority of patients were male (93.6%). Pertrochantenteric fractures were the most common injuries encountered (73.4%). Treatment included cephalomedullary nail (60.8%), arthrotomy and internal fixation (16.4%) and interfragmentary fixation with cannulated screws (6%). One case of complete neck of femur fracture had fixation failure, which required conversion to total hip arthroplasty. The overall union rate was 69.6%, and 6.3% of patients developed a fracture-related infection in cases who completed follow-up. The study shows an acceptable union rate when managing these fractures and a low risk of infection. As challenging as they are, individual approaches for each fracture and managing each fracture according to their merits yield acceptable outcomes

Aims. Dual plating of distal femoral fractures with medial and lateral implants has been performed to improve construct mechanics and alignment, in cases where isolated lateral plating would be insufficient. This may potentially compromise vascularity, paradoxically impairing healing. This study investigates effects of single versus dual plating on distal femoral vascularity. Methods. A total of eight cadaveric lower limb pairs were arbitrarily assigned to either 1) isolated lateral plating, or 2) lateral and medial plating of the distal femur, with four specimens per group. Contralateral limbs served as matched controls. Pre- and post-contrast MRI was performed to quantify signal intensity enhancement in the distal femur. Further evaluation of intraosseous vascularity was done with barium sulphate infusion with CT scan imaging. Specimens were then injected with latex medium and dissection was completed to assess extraosseous vasculature. Results. Quantitative MRI revealed a mean reduction of 21.2% (SD 1.3%) of arterial contribution in the lateral plating group and 25.4% (SD 3.2%) in the dual plating group (p = 0.051); representing a mean decrease in arterial contribution of 4.2%. The only significant difference found between both experimental groups was regionally, at the lateral aspect of the distal femur with a mean drop in arterial contribution in the lateral plating group of 18.9% (SD 2.6%) versus 24.0% (SD 3.2%) in the dual plating group (p = 0.048), representing a mean decrease in arterial contribution of 5.1%. Gross dissection revealed complete destruction of periosteal vessels underneath either medial or lateral plates in both groups. The network of genicular branches contributing to the posterior and distal femoral condyles was preserved in all specimens. A medial vascular pedicle was found dividing from the superficial femoral artery at a mean 12.7 cm (SD 1.7) proximal to the medial epicondyle and was undisrupted in the dual plating group. Conclusion. Lateral locking-plate application resulted in mean 21.2% reduction in distal femur vascularity. Addition of medial plates did not further markedly decrease vascularity. As such, the majority of the vascular insult occurred with lateral plating alone. Supplemental medially based fixation did not lead to marked devascularization of the distal femur, and should therefore be considered in the setting of comminution and poor bone stock in distal femoral fractures. Further clinical research is required to confirm the results of this study. Cite this article: Bone Joint J 2020;102-B(4):530–538

Introduction. The use of vascularised fibula grafts is an accepted method for reconstructing the distal femur following resection of malignant childhood tumours. Limitations relate to the mismatch of the cross-sectional area of the transplanted fibula graft and thel ocal bone, instability of the construct and union difficulties. We present midterm results of a unique staged technique—an immediate defect reconstruction using a double-barrel vascularised fibula graft set in in A-frame configuration and a subsequent intramedullary femoral lengthening. Materials & Methods. We retrospectively included 10 patients (mean age 10 y)with an osteosarcoma of the distal femur, who were treated ac-cording to the above-mentioned surgical technique. All patients were evaluated with regards to consolidation of the transplanted grafts, hypertrophy at the graft-host junctions, leg length discrepancies, lengthening indices, complications as well as functional outcome. Results. The mean defect size after tumour resection was 14.5 cm, the mean length of the harvested fibula graft 22 cm, resulting in a mean (acute) shortening of 4.7 cm (in 8 patients). Consolidation was achieved in all cases, 4 patients required supplementary bone grafting. Hypertrophy at the graft-host junctions was observed in78% of the evaluable junctions. In total 11 intramedullary lengthening procedures in 9 patients had been performed at the last follow up. The mean Muskuloskeletal Society Rating Scale(MSTS) score of the evaluable 9 patients was 85% (57% to 100%)with good or excellent results in 7 patients. Conclusions. A-frame vascularised fibula reconstructions showed encouraging results with respect to defect reconstruction, length as well as function and should therefore be considered a valuable option for reconstruction of the distal femur after osteosarcoma resection. The surgical implementation is demanding though, which is emphasized by the considerable high number of com-plications requiring surgical intervention, even though most were not serious

Resection of the proximal femur raises several challenges to the orthopedic oncology surgeon. Among these is the re-establishment of the abductor mechanism that might impacts on hip function. Extent of tumor resection and surgeons’ preferences dictate the reconstruction method of the abductors. While some surgeons advocate the necessity of greater trochanter (GT) preservation whenever possible, others attempt direct soft tissues reattachment to the prosthesis. Sparse data in the literature evaluated the outcomes of greater trochanter fixation to the proximal femur megaprosthesis. This is a retrospective monocentric study. All patients who received a proximal femoral replacement after tumor resection between 2005 and 2021 with a minimum follow-up of three months were included. Patients were divided into two groups: (1) those with preserved GT reattached to the megaprosthesis and (2) those with direct or indirect (tenodesis to fascia lata) abductor muscles reattachment. Both groups were compared for surgical outcomes (dislocation and revision rates) and functional outcomes (Trendelenburg gait, use of walking-assistive device and abductor muscle strength). Additionally patients in group 1 were subdivided into patients who received GT reinsertion using a grip and cables and those who got direct GT reinsertion using suture materials and studied for GT displacement at three, six and 12 months. Time to cable rupture was recorded and analyzed through a survival analysis. Fifty-six patients were included in this study with a mean follow-up of 45 months (3-180). There were 23 patients with reinserted GT (group 1) and 33 patients with soft tissue repair (group 2). Revision rate was comparable between both groups(p=0.23); however, there were more dislocations in group 2 (0/23 vs 6/33; p=0.037). Functional outcomes were comparable, with 78% of patients in group 1 (18/23) and 73% of patients in group 2 (24/33) that displayed a Trendelenburg gait (p=0.76). In group 1, 70% (16/23) used walking aids compared to 79% of group 2 (27/33) (p=0.34). Mean abductor strength reached 2.7 in group 1 compared to 2.3 in group 2 (p=0.06). In group 1, 16 of the 23 patients had GT reinsertion with grip and cables. Median survival of cables for these 16 patients reached 13 months in our series. GT displacement reached a mean of two mm, three mm, and 11 mm respectively at three, six and 12 months of follow-up in patients with grip and cables compared to 12 mm, 24 mm and 26 mm respectively at the same follow-up intervals in patients with GT stand-alone suture reinsertion(p<0.05). Although GT preservation and reinsertion did not improve functional outcomes after proximal femur resection and reconstruction with a megaprosthesis, it was significantly associated with lower dislocation rate despite frequent cable failure and secondary GT migration. No cable or grip revision or removal was recorded. Significantly less displacement was observed in patients for whom GT reattachment used plate and cables rather than sutures only. Therefore we suggest that GT should be preserved and reattached whenever possible and that GT reinsertion benefits from strong materials such as grip and cables

Introduction. Correction of multiplanar bone deformities in children is indicated for prevention of secondary orthopaedic complications. Different problems related to surgical intervention were reported: non-union, delayed union, recurrent deformity, refracture, nerve palsy and pin tract infection. The aim of this study was to show the results of children femur and tibia bowing deformities by Ilizarov technique. Materials and Methods. We analysed 27 cases of children femur and tibia bowing deformities under the age of 13 yrs. Simultaneous deformity correction in femur and tibia was done with Ilizarov device in ipsilateral side. Contralateral side was operated after 14 days. Results. The duration of Ilizarov fixation was 130 days on an average. The deformity correction was achieved with a proper alignment in all the cases. Conclusions. Bowing of femur and tibia can be corrected simultaneously by Ilizarov fixation with minimum complications. There were no recurrent deformities in our cases

Dual plating of the medial and lateral distal femur has been proposed to reduce angular malunion and hardware failure secondary to delayed union or nonunion. This strategy improves the strength and alignment of the construct, but it may compromise the vascularity of the distal femur paradoxically impairing healing. This study investigates the effect of dual plating versus single plating on the perfusion of the distal femur. Ten matched pairs of fresh-frozen cadaveric lower extremities were assigned to either isolated lateral plating or dual plating of a single limb. The contralateral lower extremity was used as a matched control. A distal femoral locking plate was applied to the lateral side of ten legs using a standard sub-vastus approach. Five femurs had an additional 3.5mm reconstruction plate applied to the medial aspect of the distal femur using a medial sub-vastus approach. The superficial femoral artery and the profunda femoris were cannulated at the level of the femoral head. Gadolinium MRI contrast solution (3:1 gadolinium to saline ration) was injected through the arterial cannula. High resolution fat-suppressed 3D gradient echo sequences were completed both with and without gadolinium contrast. Intra-osseous contributions were quantified within a standardized region of interest (ROI) using customized IDL 6.4 software (Exelis, Boulder, CO). Perfusion of the distal femur was assessed in six different zones. The signal intensity on MRI was then quantified in the distal femur and comparison was made between the experimental plated limb and the contralateral, control limb. Following completion of the MRI protocol, the specimens were injected with latex medium and the extra-osseous vasculature was dissected. Quantitative MRI revealed that application of the lateral distal femoral locking plate reduced the perfusion of the distal femur by 21.7%. Within the dual plating group there was a reduction in perfusion by 24%. There was no significant difference in the perfusion between the isolated lateral plate and the dual plating groups. There were no regional differences in perfusion between the epiphyseal, metaphyseal or meta-diaphyseal regions. Specimen dissection in both plating groups revealed complete destruction of any periosteal vessels that ran underneath either the medial or lateral plates. Multiple small vessels enter the posterior condyles off both superior medial and lateral geniculate arteries and were preserved in all specimens. Furthermore, there was retrograde flow to the distal most aspect of the condyles medially and laterally via the inferior geniculate arteries. The medial vascular pedicle was proximal to the medial plate in all the dual plated specimens and was not disrupted by the medial sub-vastus approach in any specimens. Fixation of the distal femur via a lateral sub-vastus approach and application of a lateral locking plate results in a 21% reduction in perfusion to the distal femur. The addition of a medial 3.5mm reconstruction plate does not significantly compromise the vascularity of the distal femur. The majority of the vascular insult secondary to open reduction, internal fixation of the distal femur occurs with application of the lateral locking plate

Periprosthetic femur fracture (PPF) are heterogeneous, complex, and thought to be increasingly prevalent. The aims were to evaluate PPF prevalence, casemix, management, and outcomes.

This nationwide study included all PPF patients aged >50 years from 16 Scottish hospitals in 2019. Variables included: demographics; implant and fracture factors; management factors, and outcomes.

There were 332 patients, mean age 79.5 years, and 220/332 (66.3%) were female. One-third (37.3%) were ASA1-2 and two-thirds (62.3%) were ASA3+, 91.0% were from home/sheltered housing, and median Clinical Frailty Score was 4.0 (IQR 3.0). Acute medical issues featured in 87/332 (26.2%) and 19/332 (5.7%) had associated injuries. There were 251/332 (75.6%) associated with a proximal femoral implant, of which 232/251 (92.4%) were arthroplasty devices (194/251 [77.3%] total hip, 35/251 [13.9%] hemiarthroplasty, 3/251 [1.2%] resurfacing). There were 81/332 (24.4%) associated with a distal femoral implant (76/81 [93.8%] were total knee arthroplasties). In 38/332 (11.4%) there were implants proximally and distally. Most patients (268/332; 80.7%) were treated surgically, with 174/268 (64.9%) requiring fixation only and 104/268 (38.8%) requiring an arthroplasty or combined solution. Median time to theatre was longer for arthroplasty versus fixation procedures (120 vs 46 hours), and those requiring inter-hospital transfer waited longer (94 vs 48 hours).

Barriers to investigating PPF include varied classification, coding challenges, and limitations of existing registries. This is the first study to examine a national PPF cohort and presents important data to guide service design and research. Additional findings relating to fracture patterns, implant types, surgeon skill-mix, and outcomes are reported herein.

A painful “dreaded black line” (DBL) has been associated with progression to complete fractures in atypical femur fractures (AFF). Adjacent sclerosis, an unrecognized radiological finding, has been observed in relation to the DBL. We document its incidence, associated features, demographics and clinical progression. We reviewed plain radiographs of 109 incomplete AFFs between November 2006 and June 2021 for the presence of sclerosis adjacent to a DBL. Radiographs were reviewed for location of lesions, and presence of focal endosteal or periosteal thickening. We collected demographical data, type and duration of bisphosphonate therapy, and progression to fracture or need for prophylactic stabilization, with a 100% follow up of 72 months (8 – 184 months). 109 femurs in 86 patients were reviewed. Seventeen sclerotic DBLs were observed in 14 patients (3 bilateral), involving 15.6% of all femora and 29.8% of femora with DBLs. Location was mainly subtrochanteric (41.2%), proximal diaphyseal (35.3%) and mid-diaphyseal (23.5%), and were associated with endosteal or periosteal thickening. All patients were female, mostly Chinese (92.9%), with a mean age of 69 years. 12 patients (85.7%) had a history of alendronate therapy, and the remaining 2 patients had zoledronate and denosumab therapy respectively. Mean duration of bisphosphonate therapy was 62 months. 4 femora (23.5%) progressed to complete fractures that were surgically managed, whilst 6 femora (35.3%) required prophylactic fixation. Peri-lesional sclerosis in DBL is a new radiological finding in AFFs, predominantly found in the proximal half of the femur, at times bilateral, and are always associated with endosteal or periosteal thickening. As a high proportion of patients required surgical intervention, these lesions could suggest non-union of AFFs, similar to the sclerotic margins commonly seen in fractures with non-union. The recognition of and further research into this new feature could shed more light on the pathophysiological progression of AFFs

Neck of femur fractures are a common trauma presentation and patients with a history of malignancy are sent for long leg femur views (LLF), to exclude a distal lesion which would alter the management plan (Intra-medullary nail/Long stem Hemiarthroplasty). The aim of this is to identify incidence of malignancy on LLF views, the length of time in between each xray (XR) and to identify demographics. Data was retrospectively collected from 01/01/2021 to 31/01/2021 from a single centre. All patients admitted to the Queen Elizabeth University Hospital had their electronic records (Bluespier, PACS, Clinical Portal) accessed. These confirmed if patients had a past medical history of malignancy, if they had LLF view and the time differences between diagnostic pelvis XR and LLF XR. A total of 784 patients were identified in the specified time period. Of these, 138 were identified with a malignancy and there were 85 LLF views completed. LLF views diagnosed 1 patient with known prostate cancer that had a new distal femoral metastasis (Incidence = 1.28 cases per 1000). This patient underwent further imaging (MRI Femur) and received a long stem hip hemiarthroplasty. The average length of wait between the images was 9 hours 27 minutes. LLF views can alter management of patients with malignancy and are therefore useful to perform. There can be a long delay between each image. Therefore we recommend imaging tumour with common bony metastasis (Renal, Thyroid, Breast, Prostrate, Lung) and other remaining tumours with known secondary metastasis. Imaging primary low risk (eg basal cell carcinoma) can lead to long delays in a frail patient cohort and consideration should be given to rationalise appropriate use of resources

Aims

The aim of this retrospective study was to assess the incidence of early periprosthetic femoral fracture (PFF) associated with Charnley-Kerboull (CK) femoral components cemented according to the ‘French paradox’ principles through the Hueter anterior approach (HAA) in patients older than 70 years.

Infected non-unions of proximal femoral fractures are difficult to treat. If debridement and revision fixation is unsuccessful, staged revision arthroplasty may be required. Non-viable tissue must be resected, coupled with the introduction of an antibiotic-eluting temporary spacer prior to definitive reconstruction. Definitive tissue microbiological diagnosis and targeted antibiotic therapy are required. In cases of significant proximal femoral bone loss, spacing options are limited. We present a case of a bisphosphonate-induced subtrochanteric fracture that progressed to infected non-union. Despite multiple washouts and two revision fixations, the infection remained active with an unfavourable antibiogram. The patient required staged revision arthroplasty including a proximal femoral resection. To enable better function by maintaining leg length and offset, a custom-made antibiotic-eluting articulating temporary spacer, the Cement-a-TAN, was fabricated. Using a trochanteric entry cephalocondylar nail as a scaffold, bone cement was moulded in order to fashion an anatomical, patient-specific, proximal femoral spacer. Following resolution of the infection, the Cement-a-TAN was removed and a proximal femoral arthroplasty was successfully performed. Cement-a-TAN is an excellent temporary spacing technique in staged proximal femoral replacement for infected non-union of the proximal femur where there has been significant bone loss. It preserves mobility and maintains leg length, offset and periarticular soft-tissue tension

Aim. Differentiation of infected (INF) nonunion from aseptic (AS) nonunion is crucial for the choice of intra- and postoperative treatment. Preoperative diagnosis of infected nonunion is challenging, especially in case of low-grade infection lacking clinical signs of infection. Standard blood markers such as C-reactive protein or leucocyte count do not aid in preoperative diagnosis. Proteomic profiling has shown promising results for differentiation of numerous chronic disease states, and in this study was applied to preoperative blood samples of patients with nonunion in an attempt to identify potential biomarkers. Method. This prospective multicenter study enrolled patients undergoing revision surgery of femur or tibia nonunion. Patients with implant removal after regular fracture healing (HEAL) were included as a control-group. Preoperative blood samples, intraoperative tissue samples, sonication of osteosynthesis material and 1-year-follow-up questionnaire were taken. Nonunion patients were grouped into INF or AS after assessing bacterial culture and histopathology of retrieved samples. Diagnosis of infection followed the fracture related infection consensus group criteria, with additional consideration of healing one year after revision surgery. Targeted proteomics was used to investigate a predefined panel of 45 cytokines in preoperative blood samples. Statistical differences were calculated with Kruskal Wallis and Dunn's post hoc test. Cytokines with less than 80% of samples being above the lower limit of detection range (LLDR) were excluded for this study. Results. We recruited 62 AS, 43 INF and 32 HEAL patients. Patients in the two nonunion groups (INF and AS) did not differ concerning smoking, diabetes or initial open or closed fracture. Thirty-two cytokines were above LLDR in >80% of patients. INF patients showed a significant difference in expression of 8 cytokines compared to AS, with greatest differences observed for Macrophage Colony Stimulating Factor 1 (MCSF-1) and Hepatocyte Growth Factor (HGF) (p<0.01). In comparing AS with HEAL patients, 9 cytokines displayed significant differences, including interleukin (IL)-6, Vascular Endothelial Growth Factor A (VEGFA), Matrix Metalloproteinase 1 (MMP-1). Comparison of INF with HEAL patients revealed significantly different expression of 20 cytokines, including. IL-6, IL-18, VEGFA or MMP-1. Conclusions. Our study revealed differences in plasma cytokine profile of blood samples from INF and AS patients. Although no single biomarker is sufficient to differentiate these patients preoperatively in isolation, future multivariant analysis of this cytokine data in combination with clinical characteristics may provide valuable diagnostic insights. Funded by German Social Accident Insurance (FF-FR 0276) and AO Trauma (AR2021_04)

Osteomyelitis is an inflammatory condition accompanied by the destruction of bone and caused by an infecting microorganism. Open contaminated fractures can lead to the development of osteomyelitis of the fractured bone in 3-25% of cases, depending on fracture type, degree of soft-tissue injury, degree of microbial contamination, and whether systemic and/or local antimicrobial therapies have been administered. Untreated, infection will ultimately lead to non-union, chronic osteomyelitis, or amputation. We report a case series of 10 patients that presented with post-operative infected non-union of the distal femur with or without prior surgery. The cases were performed at Padmashree Dr. D. Y. Patil Hospital, Nerul, Navi Mumbai, India. All the patients’ consents were taken for the study which was carried out in accordance with the Helsinki Declaration. The methodology involved patients undergoing a two-stage procedure in case of no prior implant or a three-stage procedure in case of a previous implant. Firstly, debridement and implant removal were done. The second was a definitive procedure in form of knee arthrodesis with ring fixator and finally followed by limb lengthening surgery. Arthrodesis was planned in view of infection, non-union, severe arthritic, subluxated knee, stiff knee, non-salvage knee joint, and financial constraints. After all the patients demonstrated wound healing in 3 months along with good radiographic osteogenesis at the knee arthrodesis site, limb lengthening surgeries by tibial osteotomy were done to overcome the limb length discrepancy. Distraction was started and followed up for 5 months. All 10 patients showed results with sound knee arthrodesis and good osteogenesis at the osteotomy site followed by achieving the limb length just 1-inch short from the normal side to achieve ground clearance while walking. Our case series is unique and distinctive as it shows that when patients with infected nonunion of distal femur come with the stiff and non-salvage knee with severe arthritic changes and financial constraints, we should consider knee arthrodesis with Ilizarov ring fixator followed by limb lengthening surgery

Femoral cement-in-cement revision is a well described technique to reduce morbidity and complications in hip revision surgery. Traditional techniques for septic revision necessitate removal of all bone cement from the femur. In our two institutions, we have been using a cement-in-cement technique, leaving the distal femoral cement in selected cases for septic hip revision surgery. Between February 2010 and September 2019, 89 patients with prosthetic hip infection underwent first or single stage procedures leaving the distal femoral cement in situ and performing a cement-in-cement revision. The mean patient age was 72.0 years (24–92). The median time from the last arthroplasty procedure was 29.0 months (1–294). 81 patients underwent revision using a cemented Exeter stem, 7 patients received an articulating spacer, and one patient underwent excision arthroplasty with the distal cement left in situ. Patients received clinical and radiographic follow-up with a mean of 42.8 months (range 11.0–120.1 months). Oxford hip scores were collected from each institution's existing databases. 9 patients (10.1%) died within one year of surgery. No deaths were directly related to joint infection or the surgery. One patient was lost to follow up before one year. Of the remainder, 7 patients (8.9%) required further procedures for infection and were therefore considered to be treatment failures. 6 patients (7.6%) underwent planned second stage procedures with no recurrence of infection. 7 patients (8.9%) had further surgery for non-infective reasons. The Kaplan-Meier estimate of infection free survival at one year was 93.7% (95% CI 88.4 to 99.0%). No patients underwent revision for stem loosening. Oxford hip scores were available at over one year postoperatively for 51 patients with a mean score of 30.6, and a mean gain of 11.9. In our combined cohort of patients, cement-in-cement revision had an infection eradication rate of 91.1%. Patient selection is crucial, and the procedure can only be performed when there is a well-fixed cement mantle. However, when strict criteria are followed, this technique offers potential significant benefits to surgeons performing this challenging surgery, and more importantly the patients undergoing them

Aims. The Exeter short stem was designed for patients with Dorr type A femora and short-term results are promising. The aim of this study was to evaluate the minimum five-year stem migration pattern of Exeter short stems in comparison with Exeter standard stems. Methods. In this case-control study, 25 patients (22 female) at mean age of 78 years (70 to 89) received cemented Exeter short stem (case group). Cases were selected based on Dorr type A femora and matched first by Dorr type A and then age to a control cohort of 21 patients (11 female) at mean age of 74 years (70 to 89) who received with cemented Exeter standard stems (control group). Preoperatively, all patients had primary hip osteoarthritis and no osteoporosis as confirmed by dual X-ray absorptiometry scanning. Patients were followed with radiostereometry for evaluation of stem migration (primary endpoint), evaluation of cement quality, and Oxford Hip Score. Measurements were taken preoperatively, and at three, 12, and 24 months and a minimum five-year follow-up. Results. At three months, subsidence of the short stem -0.87 mm (95% confidence interval (CI) -1.07 to -0.67) was lower compared to the standard stem -1.59 mm (95% CI -1.82 to -1.36; p < 0.001). Both stems continued a similar pattern of subsidence until five-year follow-up. At five-year follow-up, the short stem had subsided mean -1.67 mm (95% CI -1.98 to -1.36) compared to mean -2.67 mm (95% CI -3.03 to -2.32) for the standard stem (p < 0.001). Subsidence was not influenced by preoperative bone quality (osteopenia vs normal) or cement mantle thickness. Conclusion. The standard Exeter stem had more early subsidence compared with the short Exeter stem in patients with Dorr type A femora, but thereafter a similar migration pattern of subsidence until minimum five years follow-up. Both the standard and the short Exeter stems subside. The standard stem subsides more compared to the short stem in Dorr type A femurs. Subsidence of the Exeter stems was not affected by cement mantle thickness. Cite this article: Bone Jt Open 2023;4(7):507–515

Proximal femur fractures are common in the elderly population. The aim of this study was to determine the relationship between fracture type and proximal femoral geometric parameters. We retrospectively studied the electronic medical records of 85 elderly patients over 60 years of age who were admitted to the orthopedic department with hip fractures between January 2016 and January 2018 in a training and research hospital in Turkey. Age, fracture site, gender, implant type and proximal femoral geometry parameters (neck shaft angle [NSA], center edge angle [CEA], femoral head diameter [FHD], femoral neck diameter [FND], femoral neck axial length [FNAL], hip axial length [HAL], and femoral shaft diameter [FSD]) were recorded. Patients with femoral neck fractures and femur intertrochanteric fractures were divided into two groups. The relationship between proximal femoral geometric parameters and fracture types was examined. SPSS 25.0 (IBM Corparation, Armonk, New York, United States) program was used to analyze the variables. Independent samples t test was used to compare the fracture types according to NSA, FHD, FND and FSD variables. A statistically significant difference was found in FSD (p=0,002) and age (p=0,019). FSD and age were found to be greater in intertrochanteric fractures than neck fractures. Gender, site, CEA, FNAL, HAL, NSA, FHD and FND parametres were not significantly different. In the literature, it is seen that different results have been reached in different studies. In a study conducted in the Chinese population, a significant difference was found between the two groups in NSA, CEA and FNAL measurements. In a study conducted in the Korean population, a significant difference was found only in NSA measurements. The FSD is generally associated with bone mineral densitometry in the literature and has been shown to be a risk factor for fracture formation. However, a study showing that there is a relationship between FSD and fracture type is not available in the literature. In this study; FSD was found to be higher in intertrochanteric fractures (p = 0.002). However, for the clinical significance of this difference, we think that larger patient series and biomechanical studies are needed

Aims. Accurate estimations of the risk of fracture due to metastatic bone disease in the femur is essential in order to avoid both under-treatment and over-treatment of patients with an impending pathological fracture. The purpose of the current retrospective in vivo study was to use CT-based finite element analyses (CTFEA) to identify a clear quantitative differentiating factor between patients who are at imminent risk of fracturing their femur and those who are not, and to identify the exact location of maximal weakness where the fracture is most likely to occur. Methods. Data were collected on 82 patients with femoral metastatic bone disease, 41 of whom did not undergo prophylactic fixation. A total of 15 had a pathological fracture within six months following the CT scan, and 26 were fracture-free during the five months following the scan. The Mirels score and strain fold ratio (SFR) based on CTFEA was computed for all patients. A SFR value of 1.48 was used as the threshold for a pathological fracture. The sensitivity, specificity, positive, and negative predicted values for Mirels score and SFR predictions were computed for nine patients who fractured and 24 who did not, as well as a comparison of areas under the receiver operating characteristic curves (AUC of the ROC curves). Results. The sensitivity of SFR was 100% compared with 88% for the Mirels score, and the specificity of SFR was 67% compared with 38% for the Mirels score. The AUC was 0.905 for SFR compared with 0.578 for the Mirels score (p = 0.008). Conclusion. All the patients who sustained a pathological fracture of the femur had an SFR of > 1.48. CTFEA was far better at predicting the risk of fracture and its location accurately compared with the Mirels score. CTFEA is quick and automated and can be incorporated into the protocol of CT scanners. Cite this article: Bone Joint J 2020;102-B(5):638–645

Aims

In this study, we aimed to explore surgical variations in the Femoral Neck System (FNS) used for stable fixation of Pauwels type III femoral neck fractures.

INTRODUCTION. The magnitude of principal strain is indicative of the risks of femoral fracture,. 1,2. while changes in femoral strain energy density (SED) after total hip arthroplasty (THA) have been associated with bone remodeling stimulus. 3. Although previous modeling studies have evaluated femoral strains in the intact and implanted femur under walking loads through successfully predicting physiological hip contact force and femoral muscle forces,. 1,2,3. strains during ‘high load’ activities of daily living have not typically been evaluated. Hence, the objective of this study was to compare femoral strain between the intact and the THA implanted femur under peak loads during simulated walking, stair descent, and stumbling. METHODS. CTs of three cadaveric specimens were used to develop finite element (FE) models of intact and implanted femurs. Implanted models included a commercially-available femoral stem (DePuy Synthes, Warsaw, IN, USA). Young's moduli of the composite bony materials were interpolated from Hounsfield units using a CT phantom and established relationships. 4. Peak hip contact force and femoral muscle forces during walking and stair descent were calculated using a lower extremity musculoskeletal model. 5. and applied to the femur FE models (Fig. 1). While maintaining the peak hip contact forces, muscle forces were further adjusted using an iterative optimization approach in FE models to reduce the femur deflection to the reported physiological range (< 5 mm). 2. Femoral muscle forces during stumbling were estimated utilizing the same optimization approach with literature-reported hip contact forces as input. 6. Maximum and minimum principal strains were calculated for each loading scenario. Changes in SED between intact and THA models were calculated in bony elements around the stem. RESULTS. As expected, high loads during stumbling resulted in the highest peak principal strains along femoral diaphysis (THA: 3179±523 and −4559±629 με; intact: 4232±818 and −5853±204 με) compared to stair descent and typically evaluated gait loads (THA: 1741±363 and −1893±76 με; intact: 2256±887 and −2509±493 με; Fig. 2). Principal strains in THA models peaked close to the tip of the femoral stem across three activities, compared with proximally located peak principal strains in the intact models (Fig. 2). Bony elements located medially and laterally to the femoral stem showed decreased SED after THA, while increased SED was observed in elements distal to the femoral stem (Fig. 3). DISCUSSION. Using appropriately distributed muscle forces, our model predicted similar peak principal strains and SED differences compared with reported values during walking (peak principal strains: ±1500 to ±2000 με. 1,2. ; SED differences: ± 0.02 MPa. 3. ). In addition to the close to failure level principal strains, stumbling showed the most noticeable changes in SED compared with the other two activities. Results suggest iterative bone remodeling simulations should include a composite of activities-of-daily-living loading conditions as well as appropriately distributed muscle forces. For any figures or tables, please contact authors directly

Advances in cancer therapy have prolonged patient survival even in the presence of disseminated disease and an increasing number of cancer patients are living with metastatic bone disease (MBD). The proximal femur is the most common long bone involved in MBD and pathologic fractures of the femur are associated with significant morbidity, mortality and loss of quality of life (QoL). Successful prophylactic surgery for an impending fracture of the proximal femur has been shown in multiple cohort studies to result in longer survival, preserved mobility, lower transfusion rates and shorter post-operative hospital stays. However, there is currently no optimal method to predict a pathologic fracture. The most well-known tool is Mirel's criteria, established in 1989 and is limited from guiding clinical practice due to poor specificity and sensitivity. The ideal clinical decision support tool will be of the highest sensitivity and specificity, non-invasive, generalizable to all patients, and not a burden on hospital resources or the patient's time. Our research uses novel machine learning techniques to develop a model to fill this considerable gap in the treatment pathway of MBD of the femur. The goal of our study is to train a convolutional neural network (CNN) to predict fracture risk when metastatic bone disease is present in the proximal femur. Our fracture risk prediction tool was developed by analysis of prospectively collected data of consecutive MBD patients presenting from 2009–2016. Patients with primary bone tumors, pathologic fractures at initial presentation, and hematologic malignancies were excluded. A total of 546 patients comprising 114 pathologic fractures were included. Every patient had at least one Anterior-Posterior X-ray and clinical data including patient demographics, Mirel's criteria, tumor biology, all previous radiation and chemotherapy received, multiple pain and function scores, medications and time to fracture or time to death. We have trained a convolutional neural network (CNN) with AP X-ray images of 546 patients with metastatic bone disease of the proximal femur. The digital X-ray data is converted into a matrix representing the color information at each pixel. Our CNN contains five convolutional layers, a fully connected layers of 512 units and a final output layer. As the information passes through successive levels of the network, higher level features are abstracted from the data. The model converges on two fully connected deep neural network layers that output the risk of fracture. This prediction is compared to the true outcome, and any errors are back-propagated through the network to accordingly adjust the weights between connections, until overall prediction accuracy is optimized. Methods to improve learning included using stochastic gradient descent with a learning rate of 0.01 and a momentum rate of 0.9. We used average classification accuracy and the average F1 score across five test sets to measure model performance. We compute F1 = 2 x (precision x recall)/(precision + recall). F1 is a measure of a model's accuracy in binary classification, in our case, whether a lesion would result in pathologic fracture or not. Our model achieved 88.2% accuracy in predicting fracture risk across five-fold cross validation testing. The F1 statistic is 0.87. This is the first reported application of convolutional neural networks, a machine learning algorithm, to this important Orthopaedic problem. Our neural network model was able to achieve reasonable accuracy in classifying fracture risk of metastatic proximal femur lesions from analysis of X-rays and clinical information. Our future work will aim to externally validate this algorithm on an international cohort

The Masquelet technique is a variable method for treating critical-sized bone defects, but there is a need to develop a technique for promoting bone regeneration. In recent studies of bone fracture healing promotion, macrophage-mesenchymal stem cell (MSC) cross-talk has drawn attention. This study aimed to investigate macrophage expression in the induced membrane (IM) of the Masquelet technique using a mouse critical-sized bone defect model. The study involved a 3-mm bone defect created in the femur of mice and fixed with a mouse locking plate. The Masquelet (M) group, in which a spacer was inserted, and the Control (C) group, in which the defect was left intact, were established. Additionally, a spacer was inserted under the fascia of the back (B group) to form a membrane due to the foreign body reaction. Tissues were collected at 1, 2, and 4 weeks after surgery (n=5 in each group), and immunostaining (CD68, CD163: M1, M2 macrophage markers) and RT-qPCR were performed to investigate macrophage localization and expression in the tissues. The study found that CD68-positive cells were present in the IM of the M group at all weeks, and RT-qPCR showed the highest CD68 expression at 1 week. In addition, there was similar localization and expression of CD163. The C group showed lower expression of CD68 and CD163 than the M group at all weeks. The B group exhibited CD68-positive cells in the fibrous capsule and CD163-positive cells in the connective tissue outside the capsule, with lower expression of both markers compared to the M group at all weeks. Macrophage expression in IM in M group had different characteristics compared to C group and B group. These results suggest that the IM differs from the fibrous capsules due to the foreign body reaction, and the macrophage-MSC cross-talk may be involved in Masquelet technique

Advances in cancer therapy have prolonged cancer patient survival even in the presence of disseminated disease and an increasing number of cancer patients are living with metastatic bone disease (MBD). The proximal femur is the most common long bone involved in MBD and pathologic fractures of the femur are associated with significant morbidity, mortality and loss of quality of life (QoL). Successful prophylactic surgery for an impending fracture of the proximal femur has been shown in multiple cohort studies to result in patients more likely to walk after surgery, longer survival, lower transfusion rates and shorter post-operative hospital stays. However, there is currently no optimal method to predict a pathologic fracture. The most well-known tool is Mirel's criteria, established in 1989 and is limited from guiding clinical practice due to poor specificity and sensitivity. The goal of our study is to train a convolutional neural network (CNN) to predict fracture risk when metastatic bone disease is present in the proximal femur. Our fracture risk prediction tool was developed by analysis of prospectively collected data for MBD patients (2009–2016) in order to determine which features are most commonly associated with fracture. Patients with primary bone tumors, pathologic fractures at initial presentation, and hematologic malignancies were excluded. A total of 1146 patients comprising 224 pathologic fractures were included. Every patient had at least one Anterior-Posterior X-ray. The clinical data includes patient demographics, tumor biology, all previous radiation and chemotherapy received, multiple pain and function scores, medications and time to fracture or time to death. Each of Mirel's criteria has been further subdivided and recorded for each lesion. We have trained a convolutional neural network (CNN) with X-ray images of 1146 patients with metastatic bone disease of the proximal femur. The digital X-ray data is converted into a matrix representing the color information at each pixel. Our CNN contains five convolutional layers, a fully connected layers of 512 units and a final output layer. As the information passes through successive levels of the network, higher level features are abstracted from the data. This model converges on two fully connected deep neural network layers that output the fracture risk. This prediction is compared to the true outcome, and any errors are back-propagated through the network to accordingly adjust the weights between connections. Methods to improve learning included using stochastic gradient descent with a learning rate of 0.01 and a momentum rate of 0.9. We used average classification accuracy and the average F1 score across test sets to measure model performance. We compute F1 = 2 x (precision x recall)/(precision + recall). F1 is a measure of a test's accuracy in binary classification, in our case, whether a lesion would result in pathologic fracture or not. Five-fold cross validation testing of our fully trained model revealed accurate classification for 88.2% of patients with metastatic bone disease of the proximal femur. The F1 statistic is 0.87. This represents a 24% error reduction from using Mirel's criteria alone to classify the risk of fracture in this cohort. This is the first reported application of convolutional neural networks, a machine learning algorithm, to an important Orthopaedic problem. Our neural network model was able to achieve impressive accuracy in classifying fracture risk of metastatic proximal femur lesions from analysis of X-rays and clinical information. Our future work will aim to validate this algorithm on an external cohort

Aims. The consensus is that bipolar hemiarthroplasty (BHA) in allograft-prosthesis composite (APC) reconstruction of the proximal femur following primary tumour resection provides more stability than total hip arthroplasty (THA). However, no comparative study has been performed. In this study, we have compared the outcome and complication rates of these two methods. Methods. In a retrospective study, 57 patients who underwent APC reconstruction of proximal femur following the primary tumour resection, either using BHA (29) or THA (28), were included. Functional outcome was assessed using the Musculoskeletal Tumour Society (MSTS) scoring system and Harris Hip Score (HHS). Postoperative complications of the two techniques were also compared. Results. The mean follow-up of the patients was 8.3 years (standard deviation (SD) 5.5) in the BHA and 6.9 years (SD 4.7) in the THA group. The mean HHS was 65 (SD 16.6) in the BHA group and 88 (SD 11.9) in the THA group (p = 0.036). The mean MSTS score of the patients was 73.3% (SD 16.1%) in the BHA and 86.7% (SD 12.2%) in the THA group (p = 0.041). Limping was recorded in 19 patients (65.5%) of the BHA group and five patients (17.8%) of the THA group (p < 0.001). Dislocation occurred in three patients (10.3%) of the BHA group and two patients (7.1%) of the THA group. Conclusion. While the dislocation rate was not higher in THA than with BHA, the functional outcome was significantly superior. Based on our results, we recommend THA in APC reconstruction of the proximal femur. Cite this article: Bone Joint J 2020;102-B(4):524–529

Introduction. The posterior condylar axis of the knee is the most common reference for femoral anteversion. However, the posterior condyles, nor the transepicondylar axis, provide a functional description of femoral anteversion, and their appropriateness as the ideal reference has been questioned. In a natural standing positon, the femur can be internally or externally rotated, altering the functional anteversion of the native femoral neck or prosthetic stem. Uemura et al. found that the femur internally rotates by 0.4° as femoral anteversion increases every 1°. The aim of this study was to assess the relationship between femoral anteversion and the axial rotation of the femur before and after total hip replacement (THR). Method. Fifty-nine patients had a pre-operative CT scan as part of their routine planning for THR. The patients were asked to lie in a comfortable position in the CT scanner. The internal/external rotation of the femur, described as the angle between the posterior condyles and the CT coronal plane, was measured. The native femoral neck anteversion, relative to the posterior condyles, was also determined. Identical measurements were performed at one-week post-op using the same CT methodology. The relationship between femoral IR/ER and femoral anteversion was studied pre- and post-op. Additionally, the effect of changing anteversion on the axial rotation of the femur was investigated. Results. There was a strong correlation between axial rotation of the femur and femoral anteversion, both pre-and post-operatively. Pearson correlation coefficients of 0.64 and 0.66 respectively. This supported Uemura et al.'s findings that internal rotation of the femur increases with increasing anteversion. Additionally, there was a moderate correlation, r = 0.56, between the change in axial rotation of the femur and change in anteversion. This trend suggested that external rotation of the leg would increase, if stem anteversion was decreased from the native. Conclusions. Patients with high femoral anteversion may have a natural mechanism of “correction” with femoral internal rotation. Equally, patients with femoral retroversion tend to naturally externally rotate their leg. Decreasing stem anteversion from native, trended toward an increase in external rotation of the femur. This finding is supported by the clinical observation of patients with high anteversion and compensatory in-toe, who have normal foot progression angle post-operatively after having their anteversion decreased. These findings have implications when planning implant alignment in THR

Introduction. IM (Intra Medullary) nail fixation is the standard treatment for diaphyseal femur fractures and also for certain types of proximal and distal femur fractures. Despite the advances in the tribology for the same, cases of failed IM nail fixation continue to be encountered routinely in clinical practice. Common causes are poor alignment or reduction, insufficient fixation and eventual implant fatigue and failure. This study was devised to study such patients presenting to our practice and develop a predictive model for eventual failure. Materials and Methods. 57 patients who presented with failure of IM nail fixation (± infection) between Jan 2011 – Jun 2020 were included in the study and hospital records and imaging reviewed. Those fixed with any other kinds of metalwork were excluded. Classification for failure of IM nails – Type 1: Failure with loss of contact of lag screw threads in the head due to backing out and then rotational instability, Type 2A: Failure of the nail at the nail and lag screw junction, Type 2B: Failure of the screws at the nail lag screw junction, Type 3: Loosening at the distal locking sites with or without infection. X-rays reviewed and causes/site of failure noted. Results. Total patients - 57. Demography - Average age - 58.9 years, 22 Males and 35 females. Eleven patients were noted to have an infection at the fracture site that needed oral or IV antibiotics.16 patients - at least 1 cerclage wire for fracture reduction and fixation + IM Nail. Subtrochanteric fractures (42/57) were the most common to fail. In those fractures with postero-medial comminution, locking of the lag screw in position thus preventing backout can prevent failure. In type 2 failures, preventing varus fixation by early open reduction and temporary fixation with plates and screws can achieve improved results. Those with type 3 failures with periosteal reaction should be considered to be infected until proven otherwise. Conclusions. This classification for failure of IM nails in the femur can be used as a predictive model for failures and allow early recognition and intervention to tackle them

Deformity of the proximal femur in fibrous dysplasia leads to deviation of the mechanical axis of the hip, which may lead to the development of secondary osteoarthritis (OA). This study investigated the prevalence and predisposing factors for the development of OA in patients with fibrous dysplasia of the proximal femur. We reviewed the records of 209 patients from our institutional database with fibrous dysplasia of the proximal femur, investigating possible predisposing factors including patient demographics, the extent of the coxa vara deformity, the presence of peri-articular disease, and the overall burden of skeletal disease. Of the 209 patients, 24 (12%) had radiological evidence of OA in the ipsilateral hip. The prevalence was significantly higher in patients with polyostotic fibrous dysplasia compared with those with monostotic disease (p < 0.001). In a subgroup analysis of patients with polyostotic disease, the extent of deformity (quantified using the neck–shaft angle), and the presence of peri-articular disease (whether in the head of the femur or the acetabulum) were significant predictors of osteoarthritis (neck–shaft angle likelihood ratio (LR) = 0.847 per 1° increase, p = 0.004; presence of lesion in the head of the femur LR = 9.947, p = 0.027; presence of lesion in the acetabulum LR = 11.231, p = 0.014). . Our data suggest that patients with polyostotic fibrous dysplasia have a high risk of developing secondary OA of the hips. This risk is higher in patients with peri-articular disease, and those with a more severe deformity of proximal femur. Cite this article: Bone Joint J 2015;97-B:1007–11

INTRODUCTION. Over the past 40 years of knee arthroplasty, significant advances have been made in the design of knee implants, resulting in high patient satisfaction. Patellar tracking has been central to improving the patient experience, with modern designs including an optimized Q-angle, deepened trochlear groove, and thin anterior flange.[1–4] Though many of today's femoral components are specific for the left and right sides, Total Joint Orthopedics’ (TJO) Klassic® Knee System features a universal design to achieve operating room efficiencies while providing all the advancements of a modern knee. The Klassic Femur achieves this through a patented double Q-angle to provide excellent patellar tracking whether implanted in the left or the right knee (Figure 1). The present study examines a prospective cohort of 145 consecutive TKA's performed using a modern universal femur and considers patients’ pre- and post-operative Knee Society Clinical Rating System score (KSS). METHODS AND MATERIALS. 145 primary total knee arthroplasties (TKA) were performed during the study using a measured resection technique with a slope-matching tibial cut for all patients. The posterior cruciate ligament (PCL) was sacrificed to accommodate an ultra-congruent polyethylene insert. The distal femur was cut at five degrees (5°) valgus; the tibia was resected neutral (0°) alignment for valgus legs and in two degrees (2°) of varus for varus alignment. The patella was resurfaced for all patients. Patients were followed annually for up to 46 months and were evaluated using the KSS score on a 200-point scale. RESULTS. The final study group comprised 127 primary TKAs. The average age was 68 years (51–90) with 45 males and 68 females. The average weight was 110kg (range: 75–151kg) for men and 88kg (range: 50–129kg) for women. One patient deceased during the follow-up period, four required manipulation under anesthesia, and two required revision for periprosthetic joint infection. There were no failures due to patellar maltracking. No special soft tissue releases were required in any patient. Average pre-operative knee score was 107, improving to 182 at average follow-up of 41 months (36–46 months). Results are summarized in Table 1. DISCUSSION. The improvement in patient clinical experience demonstrates that a universal femoral design can achieve excellent results if it incorporates modern technologies. A double Q-angle design with a deepened trochlear groove and a thin anterior flange appears to provide excellent patellar tracking for all patients in this cohort. This study is limited to the experience of a single institution. Further study would improve the extensibility of these findings. It does show, however, that a femur using a universal design with modern patellar tracking can improve patient satisfaction with their knee following TKA. For any figures or tables, please contact the authors directly

Objectives. In this prospective cohort study, we investigated whether patient-specific finite element (FE) models can identify patients at risk of a pathological femoral fracture resulting from metastatic bone disease, and compared these FE predictions with clinical assessments by experienced clinicians. Methods. A total of 39 patients with non-fractured femoral metastatic lesions who were irradiated for pain were included from three radiotherapy institutes. During follow-up, nine pathological fractures occurred in seven patients. Quantitative CT-based FE models were generated for all patients. Femoral failure load was calculated and compared between the fractured and non-fractured femurs. Due to inter-scanner differences, patients were analyzed separately for the three institutes. In addition, the FE-based predictions were compared with fracture risk assessments by experienced clinicians. Results. In institute 1, median failure load was significantly lower for patients who sustained a fracture than for patients with no fractures. In institutes 2 and 3, the number of patients with a fracture was too low to make a clear distinction. Fracture locations were well predicted by the FE model when compared with post-fracture radiographs. The FE model was more accurate in identifying patients with a high fracture risk compared with experienced clinicians, with a sensitivity of 89% versus 0% to 33% for clinical assessments. Specificity was 79% for the FE models versus 84% to 95% for clinical assessments. Conclusion. FE models can be a valuable tool to improve clinical fracture risk predictions in metastatic bone disease. Future work in a larger patient population should confirm the higher predictive power of FE models compared with current clinical guidelines. Cite this article: F. Eggermont, L. C. Derikx, N. Verdonschot, I. C. M. van der Geest, M. A. A. de Jong, A. Snyers, Y. M. van der Linden, E. Tanck. Can patient-specific finite element models better predict fractures in metastatic bone disease than experienced clinicians? Towards computational modelling in daily clinical practice. Bone Joint Res 2018;7:430–439. DOI: 10.1302/2046-3758.76.BJR-2017-0325.R2