A prospective, randomized, controlled trial was performed to compare the outcome of treatment of unstable fractures of the proximal part of the femur with either a sliding hip screw or a short proximal femoral nail antirotation (PFNA-XS, Synthes). Eighty one patients (April 2007 – May 2008) presenting with unstable fracture of the proximal part of the femur were randomized, at the time of admission, to fixation with use of either a short proximal femoral nail antirotation (n=42) or a sliding hip screw (n= 39). The primary outcome measure was reoperation within the first postoperative year and mortality at the end of one year. Operative time, fluoroscopy time, blood loss, and any intra-operative complication were recorded for each patient. Follow-up was undertaken at 3, 6, and 12 postoperative months and yearly thereafter. Plain AP and lateral radiographs were obtained at all visits. All changes in the position of the implant, complications, or fixation failure were recorded. Hip range of motion, pain about the hip and the thigh, walking ability score and return to work status were used to compare the outcomes. There was no significant difference between 1 year mortality rates for the two groups. Mean Operative time was significantly less in PFNA group (Mean 25 min, range 19 – 56 min) than DHS group (Mean 38 min, range 28 – 70 min). Patients treated with a PFNA experienced a shorter fluoroscopy time and less blood loss. 6 patients in DHS group had implant failure as compared to none in PFNA group. The functional outcome was also better in PFNA group. When compared to DHS, PFNA-XS provides better functional outcome for unstable trochanteric fractures with less operative time, less blood loss and less complications, however one year mortality rate remains the same

Purpose. To perform comparative analysis between the results of internal fixation using proximal femoral nail system and bipolar hemiarthroplasty in pantrochanteric hip fracture in elderly patients. Materials and Methods. From January 2006 to February 2012, we reviewed 43 patients, who were treated surgically for pantrochanterichip fractures, with a minimum of 2 years follow up. The patient's age was older than 70 year old. The patients were divided into three groups and evaluated, retrospectively. The fracture reduction were regarded as satisfactory in S-OR-IF group(17 cases) and unsatisfactory in US-OR-IF group(9 cases) and the other group was treated with bipolar hemiarthroplasty (BHA group, 17 cases.). Results. At 24 months post-operation, S-OR-IF group had higher Harris scores, less pain, and better walking ability than S-OR-IF and BHA group. Six patients in the internal fixation group (one with S-OR-IF and five with US-OR-IF) had got reoperation. Conclusion. For pantrochanteric fractures of old-aged patient over 70 years old, bipolar hemiarthroplasty has few of severe complications which needs reoperation, and has good results of early ambulation. However, satisfactory reduction and internal fixation makes better clinical results in long term follow-up

Introduction. Internal fixation of pertrochanteric fractures is evolving as newer implants are being developed. Proximal Femoral Nail Antirotation (PFNA) is a recently introduced implant from AO/ASIF designed to compact the cancellous bone and may be particularly useful in unstable and osteoporotic hip fractures. This study is a single and independent centre experience of this implant used in management of acute hip fractures. Methods. 68 patients involving 68 PFNA nailing procedures done over a period of 2 years (2007–09) were included in the study. Average follow-up period of patients was 1 year. AO classification for trochanteric fractures was used to classify all the fractures. Radiological parameters including tip-apex distance and neck shaft angle measurement were assessed. Results. Average age of patients included in the study was 80 years. 18 patients died during the follow up period due to non-procedure related causes. Average tip-apex distance was 12.7 mm and radiological fracture union time was 5 months. Revision of short to a long PFNA was needed for periprosthetic fracture of shaft of femur in two patients. Two patients needed a complex total hip replacement eventually and further two patients had removal of the implant due to PFNA blade penetration through the femoral head. Discussion. PFNA is a technically demanding procedure and has a learning curve. Our experience shows that it is a useful implant in unstable pertrochanteric fracture fixation. A close radiological and clinical follow up is recommended due to the risk of late fracture and implant related complications

Aims

The aim of this study was to present the first retrieval analysis findings of PRECICE STRYDE intermedullary nails removed from patients, providing useful information in the post-market surveillance of these recently introduced devices.

Pertrochanteric femoral fractures are common and intramedullary nailing with a proximal femoral nail (PFNA®) is an accepted method for the surgical treatment. Accurate guide wire and subsequent hardware placement in the femoral neck is believed to be essential in order to avoid mechanical failure. Malpositioned implants may lead to rotational or angular malalignment or “cut out” in the femoral neck. Hip and knee arthritis might be a potential long-term consequence. The conventional technique might require multiple guidewire passes, and relies heavily on fluoroscopy. A computer-assisted surgical planning and navigation system based on 2D-fluoroscopy was developed in-house as an intraoperative guidance system for navigated guide wire placement in the femoral neck and head. To support the image acquisition process, the surgeon is supported by a so-called “zero-dose C-arm navigation” module. This tool enables a virtual radiation-free preview of the X-ray images of the femoral neck and head. The aim of this study was to compare PFNA® insertion using this system to conventional implantation technique. We hypothesised that guide wire and subsequent implant placement using our software decreases radiation exposure to the minimum of two images and reduces the number of drilling attempts. Furthermore, accuracy of implant placement in comparison to the conventional method might be improved and operation time shortened. We used 24 identical intact left femoral Sawbones® to simulate reduced pertrochanteric femoral fractures. First, we performed placement of the PFNA® into 12 Sawbones using the conventional fluoroscopic technique (group 1). Secondly, we performed placement of the PFNA® into 12 Sawbones guided by the computer-assisted surgical planning software (group 2). In each group, we first performed open and secondly minimal-invasive intramedullary nailing in six sawbones each. For minimal-invasive guide wire placement, a surgical drape imitated soft tissue coverage. Conventional and navigated technique used a C-arm fluoroscope (Siemens IsoC 3D®, Erlangen, Germany) in conventional 2D mode. Guidewire and subsequent blade placement in the femoral neck was evaluated. We documented: 1: the number of fluoroscopic images; 2: the total number of drilling attempts; 3: implant placement accuracy (3.1. Tip apex distance (TAD); 3.2. visible penetrations of the femoral neck and head; 3.3. blade-corticalis bone distance in the anteroposterior and lateral plane) and the 4: operation time. The number of fluoroscopic single shots taken to achieve an acceptable PFNA®-blade position was reduced significantly with computer-assistance by 71.5% (p<0.001) in the open and by 72,4% (p<0.001) in the minimally invasive technique. In each operation two X-rays for final documentation were taken. The average number of drilling attempts for the computer-guided system was significantly (p<0.05) less than that of the conventional technique in the minimally invasive procedure. The average number of drilling attempts showed no difference between the computer-assisted and conventional techniques in the open procedure. Accuracy of implant placement showed no difference between the computer-assisted and the conventional group. Computer assistance significantly increased the mean operation time for fixation of pertrochanteric femoral fractures with a PFNA® by 79.8% (p<0.001) in the open technique and by 54.4% (p<0.001) in the minimally invasive technique. Use of our computer-guided system for fixation of pertrochanteric femoral fractures by a PFNA® decreases the number of fluoroscopic single shots and of suboptimal guide wire passes while maintaining blade placement accuracy that is equivalent to the conventional technique. Computer-assisted surgery with our system increases the operation time and has just been tested in non-fractured sawbones. Although these results are promising, additional studies including fractured sawbones and cadaver models with extension of the navigation process to all steps of PFNA® introduction and with the goal of reducing the operation time are indispensable before integration of this navigation system into the clinical workflow

The PFNA is used routinely at the RUH for unstable peri-trochanteric and femoral fractures. Failure of operative treatment is associated with increased morbidity and financial burden. We analysed surgical and fracture factors, aiming to identify those associated with fixation failure.

Retrospective analysis of 76 consecutive patients treated with a PFNA between 2009–2012 was performed. Patient demographics were assessed, along with fracture classification, adequacy of reduction, tip apex distance (TAD) and grade of surgeon. Failure was defined as metal work failure, non-union or need for repeat procedure.

The mean age was 78.9 years (25.9–97.4). 21 were male and 49 female. There were 17 failures (24.3%) (7 required further surgery). 10 failures were per-trochanteric, 2 sub-trochanteric and 5 mid-shaft fractures. Complications included 4 broken and 6 backed-out distal locking screws, 2 blade cut-outs, 1 nail fracture and 4 non-unions. All per-trochanteric were adequately reduced with a TAD <25 mm. 11/17 had consultant supervision.

A high rate of backed-out distal locking screws was identified. We found no concerns with adequacy of reduction, TAD or consultant supervision.

Introduction

In comminuted intertrochanteric fractures, various operative options have been introduced. The purpose of this study was to determine whether there were differences in clinical and radiologic outcomes among bipolar hemiarthroplasty(BH), compression hip screw(CHS) and proximal femur nail antirotatory(PFNA) in treating comminuted intertrochanteric fractures(AO type, A2(21, 22, 23))

Long femoral nails for neck of femur fractures and prophylactic fixation have a risk of anterior cortex perforation. Previous studies have demonstrated the radius of curvature (ROC) of a femoral nail influencing the finishing point of a nail and the risk of anterior cortex perforation. This study aims to calculate a patients femoral ROC using preoperative XR and CT and therefore nail finishing position. We conducted a retrospective study review of patients with long femoral cephalomedullary nailing for proximal femur fractures (OTA/AO 31(A) and OTA/AO 32) or impending pathological fractures at a level 1 trauma centre between January 1, 2015 and December 31, 2020 with both full length lateral X-ray and CT imaging. Femoral ROC was calculated on both imaging modalities. Outcomes measured including nail finishing position, anterior cortex encroachment and impingement. The mean femoral ROC was 1026mm on CT and 1244mm on XR. CT femoral ROC strongly correlated with nail finishing point with a spearmans coefficient of 0.77. Additionally, femurs with a ROC <1000mm were associated with a higher risk of anterior encroachment (OR 6.12) and femurs with a ROC <900mm were associated with a higher risk of anterior cortex impingement (OR 6.47). To our knowledge this is the first study to compare a measured femoral ROC to nail finishing position. The use of CT to measure femoral ROC and to a lesser extent XR was able to predict both nail finishing position and risk of anterior cortex encroachment. Preoperative XRs and CTs were able to identify patients with a small femoral ROC. This predicted patients at risk of anterior cortex impingement, anterior cortex encroachment and nail finishing position. We may be able to select femoral nails that resemble the native femoral ROC and mitigate the risk of anterior cortex perforation

In the polytrauma patient, intraoperative patient positioning is one factor thought to influence pulmonary complications associated with intramedullary (IM) nailing of the femur. With regards to lateral femoral nailing, it is currently unknown as to whether the position of the injured lung contributes to changes in pulmonary function. It has been proposed that, similar to prone positioning in the ICU for acute respiratory distress syndrome management, having the injured lung in a dependent position during lateral femoral nailing would prevent barotrauma from hyperinflation and promote gas exchange in the non-dependent healthy lung. This study aims to assess the association between the position of the injured lung during lateral femoral nailing and pulmonary complications as determined by ICU LOS. This retrospective cohort study was conducted at a single level 1 trauma centre. All patients treated with IM nailing for femur fracture between 2006 and 2014 were screened for inclusion. Only patients who 1) underwent lateral femoral nailing and 2) had a significant chest injury, defined by chest Abbreviated Injury Scale (AIS) of three or greater, were included. Patients with bilateral femur fractures or symmetric bilateral thoracic injuries were excluded. Intraoperative position of the lung injury was described depending on whether the injured lung was down, or in the dependent position, during lateral femoral nailing, versus the healthy lung down. The primary outcome was ICU LOS in all study patients. Secondary analysis was performed on the subgroup of patients who were admitted to ICU prior to femoral nailing. Data analysis assessing for differences in ICU LOS between groups was performed through Wilcoxan testing. One hundred and thirteen femur fractures were included in the study. During lateral femoral nailing, 53 patients had the injured lung down and 60 patients had the healthy lung down. No differences between age, ICU admission rate, injury severity score, chest AIS or head AIS were detected between the groups. There were no detectable differences in the rate of ICU admission between patients with the injured lung down (47.2%) and patients with the healthy lung down (46.7%) (P=0.96). We were unable to detect a difference in average ICU LOS between patients who had the injured lung down (4.9 days, 95% CI 2.8 – 7) compared to patients with the healthy lung down (6 days, 95% CI 3.7 – 8.4) during lateral femoral nailing (P=0.73). When looking only at patients who were admitted to ICU prior to femoral nailing, the LOS was 10.3 days (95% CI 7 – 13.7) in injured lung down patients compared to 12.9 days (9.2 – 16.6) in healthy lung down patients (P= 0.25). In patients with chest AIS greater than three, the position of the injured lung during lateral femoral IM nailing does not appear to affect ICU LOS

This technique is a novel superior based muscle sparing approach. Acetabular reaming in all hip approaches requires femoral retraction. This technique is performed through a hole in the lateral femoral cortex without the need to retract the femur. A 5 mm hole is drilled in the lateral femur using a jig attached to the broach handle, similar to a femoral nail. Specialised instruments have been developed, including a broach with a hole going through it at the angle of the neck of the prosthesis, to allow the rotation of the reaming rod whilst protecting the femur. A special C-arm is used to push on the reaming basket. The angle of the acetabulum is directly related to the position of the broach inside the femoral canal and the position of the leg. A specialised instrument allows changing of offset and length without dislocating the hip during trialling. Some instrumentation has been used in surgery but ongoing cadaver work is being performed for proof of concept. The ability to ream through the femur has been proven during surgery. The potential risk to the bone has been assessed using finite analysis as minimal. The stress levels for any diameter maintained within a safety factor >4 compared to the ultimate tensile strength of cortical bone. The described technique allows for transfemoral acetabular reaming without retraction of the femur. It is minimally invasive and simple, requiring minimal assistance. We are incorporating use with a universal robot system as well as developing an electromagnetic navigation system. Assessment of the accuracy of these significantly cheaper systems is ongoing but promising. This approach is as minimally invasive as is possible, safe, requires minimal assistance and has a number of other potential advantages with addition of other new navigation and simple robotic attachments

Introduction. The aim of this radiographic study was to define the anatomical axis joint centre distance (aJCD) and anatomical axis joint centre ratio (aJCR) of the distal femur in the coronal plane for skeletally mature individuals. Materials and Methods. A cross-sectional radiographic study was conducted to calculate the horizontal distances between the anatomical axis and the centre of the knee at the level of the intercondylar notch and the joint line. Ratios relating these points to the width of the femur were then calculated. Results. A total of 164 radiographs were included: 91 male (55.5%) and 73 female patients (44.5%) with a mean age of 44.9 ± 18.0 years, with 79 right (48.2%) and 85 left (51.8%). The intercondylar width mean was 75.4 ± 6.8mm, the median aJCD at the notch was 3.6mm (interquartile range, IQR 2.1 – 5.1), the median aJCD at the joint line was 4.7mm (IQR 3.5 – 6.3), the aJCR at the notch 45.1 ± 2.7, and the aJCR at the joint line 43.5 ± 2.7. The intercondylar width was significantly different (p<0.001) between males (79.5 ± 5.0 mm) and females (70.4 ± 5.1 mm). A significant difference between the aJCR at the notch (p=0.003) and the aJCR at the joint line (p=0.002) was observed in males and females. No differences between the aJCD at the notch or aJCD at the joint line was observed between males versus females, left versus right and those younger versus those older than 65 years. Conclusions. This is the first objective description of the anatomic axis joint centre ratio (aJCR) of the distal femur in the coronal plane. This ratio can be used to aid the planning and execution of distal femoral deformity correction, retrograde femoral nailing, and total knee arthroplasty

Introduction. At Sheffield Children's Hospital, treatment of leg length discrepancy is a common procedure. Historically, this has been done with external fixators. With the development in intramedullary technology, internal nails have become the preferred modality for long bone lengthening in the adolescent population. However, it is important to review whether this technology practically reduces the known challenges seen and if it brings any new issues. Therefore, the aim of this review is to retrospectively evaluate the therapeutic challenges of 16 fit-bone intramedullary femoral lengthening's at Sheffield Children's Hospital between 2021–2022. Materials & Methods. The international classification of function (ICF) framework was used to differentiate outcomes. The patient's therapy notes were retrospectively reviewed for themes around structural, activity and participation limitation. The findings were grouped for analysis and the main themes presented. Results. There were 8 males, mean age 17.4 years (range 17–18) and 8 females, mean age 15.9 years (range 14–18). 5 right and 11 left femurs were lengthened. Underlying pathology varied amongst the 16 patients. All patients went into a hinged knee brace post operatively. Structural limitations included: pain, fixed flexion deformity of the knee, loss of knee flexion, quadriceps muscle lag, muscle spasms and gluteal weakness. The primary activity limitation was reduced weight bearing with altered gait pattern. Participation limitations included reduced school attendance and involvement in activities with peers. Access to Physiotherapy from local services varied dramatically. Five of the cohort have completed treatment. Conclusions. Anecdotally, intramedullary femoral lengthening nails have perceived benefits for families compared to external fixators in the adolescent population. However, there remain musculoskeletal and psychosocial outcomes requiring therapeutic management throughout the lengthening process and beyond. Therefore, quantifying these outcomes is essential for measuring the impact on each patient for comparison. To interpret these themes, we need to evaluate the outcomes objectively, this was not done consistently in this review. Future research should look at outcome measures that are sensitive to all aspects of the ICF. With an aim of improving the therapeutic treatment provided and the overall outcome for the children treated

Introduction. Pixel Value Ratio (PVR) is a radiographic measure of the relative density of the regenerate to the adjacent bone. This has been reported as an objective criterion for regenerate healing and a guide for when to allow full weight bearing (FWB) in lengthening with intramedullary telescopic nails. The threshold for which magnitude of PVR is adequate to allow bearing full weight is not yet agreed. The aim of this study was to identify from our cohort of adult limb lengthening patients the time to FWB following lengthening, the PVR at this point, and how this compared with the recommended values in the literature. Materials and Methods. A retrospective database review identified 30 adult patients treated with the PRECICE femoral nail by two senior authors. Time from completion of lengthening to instruction to fully weight bear was noted. The PVR was calculated for each cortex on plain radiographs taken at each postoperative visit following completion of lengthening. Significance was set at p <0.05. Results. The median age was 30.5 years (IQR 22.5 – 42.5), 19 male and 11 female patients were included. The underlying cause of shortening was post traumatic in 12 (40%) with the remaining due to a wide variety of causes including congenital, infective, and idiopathic leg length discrepancies. Twenty-two nails were antegrade and the mean distance lengthened was 42 mm. Median time from completion of lengthening to full weight bearing was 42 days (IQR 28 – 69). The overall mean PVR at FWB was 0.79. Each surgeon had differing protocols for weightbearing, however there was no statistical difference between time to weight bearing, nor the mean PVR at FWB. There were no implant failures, shortening, or regenerate fractures. Conclusions. We report on our cohort of adult patients treated with intramedullary lengthening nails with a mean PVR of 0.79 at time of full weightbearing. This is considerably lower than the values reported in the literature ranging from 0.90 to 0.93. We therefore suggest that weightbearing following lengthening nails can be permitted earlier than previously reported without an increased risk of complication

Purpose. To compare the clinical and radiological results between internal fixation using the proximal femoral nail system and bipolar hemiarthroplasty in reverse oblique intertrochanteric hip fracture in elderly patients. Materials and Methods. From January 2005 to July 2012, we reviewed 53 patients who had been treated surgically for reverse oblique intertrochanteric fracture and been followed up on for a minimum of 2 years. The patients, all over 70 years old, were divided into two groups for retrospective evaluation: one group was treated with open reduction and internal fixation using the proximal femoral nail system (31 cases), and the other group was treated with bipolar hemiarthroplasty (22 cases). Results. Early ambulation postoperatively and less pain at postoperative three months were significantly superior in the bipolar hemiarthroplasty group. However, by 24 months postoperatively, the open reduction and internal fixation group had higher Harris scores and correspondingly less pain than the bipolar hemiarthroplasty group. There were no significant differences in union rate, duration of hospitalization or lateral wall fracture healing between the two groups. Four patients in the open reduction and internal fixation group underwent reoperation. Conclusions. In the treatment of intertrochanteric fracture of the reverse oblique type, if the patient's health and bone quality are good, open reduction and internal fixation is considered to be the better choice. However, in cases of severe communition of fracture and poor bone quality along with high risk of early reduction failure, bipolar hemiarthroplasty is an alternative offering advantages in terms of early ambulation, less pain at early stages, and lower risk of reoperation

Introduction. The incidence of distal femoral fractures amongst elderly patients is likely to rise due to increased life expectancy. This study reports on the outcome of a series of distal femoral fractures treated by retrograde femoral nailing and then to compare the results for these patients with a series of patients with a proximal femoral fracture. Materials and/Methods. In this longitudinal cohort study, 36 patients with extra-articular distal femoral fractures were treated with a solid retrograde femoral nail. Data was collected prospectively and then compared to proximal femoral fractures (2426) treated by the same surgeon treated over the same time period. Results. Within the distal femoral group 97% of the patients were female, with a mean age of 81 years. The mean length of hospital stay amongst the distal femoral group was slightly higher (19 days) compared to the proximal femoral group (18 days). All the post-operative complications were higher amongst the distal femoral group which included deep vein thrombosis 8% vs 2%, pneumonia 5% vs 3%, superficial wound infection 5% vs 3% and deep wound infection 2% vs 1%. 5% of patients in the proximal femoral group required revision surgery whereas none in the distal femoral group did. The survival analysis curve indicated to an increased trend in mortality amongst the distal femoral group however due to the small sample size this did not reach statistical significance. Conclusions. Our study shows that there is a significant morbidity and mortality amongst patients who have sustained a distal femoral fracture. Given the significant risk that elderly patients have we propose that distal femoral fractures should be treated with prompt surgical fixation with an emphasis on early rehabilitation and safe discharge

Aims

The use of fluoroscopy in orthopaedic surgery creates risk of radiation exposure to surgeons. Appropriate personal protective equipment (PPE) can help mitigate this. The primary aim of this study was to assess if current radiation protection in orthopaedic trauma is safe. The secondary aims were to describe normative data of radiation exposure during common orthopaedic procedures, evaluate ways to improve any deficits in protection, and validate the use of electronic personal dosimeters (EPDs) in assessing radiation dose in orthopaedic surgery.

Purpose. The timing of definitive fixation for major fractures in polytrauma patients is controversial. To clarify this aspect of trauma management, we randomised patients with blunt multiple injuries to either initial definitive stabilisation of the femur shaft with an intramedullary nail or an external fixator which was converted to an intramedullary nail at a secondary procedure and documented the post-operative clinical condition. Methods. Multiply injured patients with femoral shaft fractures were randomised to either initial (<24 hours) intramedullary femoral nailing or to initial external fixation and conversion to an intramedullary nail at a later phase. Inclusion criteria: New Injury Severity Score >16 points, or 3 fractures and Abbreviated Injury Scale score >2 points and another injury (Abbreviated Injury Scale score >2 points), and age 18 to 65 years. Exclusion criteria: unstable or patients in extremis. Patients were graded as stable or borderline (increased risk of systemic complications). OUTCOMES: Incidence of acute lung injuries. Results. Ten European Centres, 165 patients, mean age 32.7 ±11.7 years. Group of intramedullary nailing, n = 94; Group of external fixation, n = 71. Pre-operatively, 121 patients were stable and 44 patients were in borderline condition. After adjusting for differences in initial injury severity, the odds of developing acute lung injury were 6.69 times greater in borderline patients who underwent intramedullary nailing in comparison to the external fixation group, P < 0.05. Conclusion. Intramedullary stabilisation of the femur fracture can affect the outcome in patients with multiple injuries. In stable patients, primary femoral nailing is associated with shorter ventilation time. In borderline patients, it is associated with a higher incidence of lung dysfunctions when compared to those that underwent initially external fixation. Therefore, the pre-operative condition should be when deciding on the type of initial fixation to perform in patients with multiple blunt injuries

Proximal Femoral Nail Antirotation (PFNA) I one of the implants commonly used to stabilise subtrochanteric fractures or communited inter/pertrochanteric fractures. The aim of this project was to assess the outcome of PFNA in a busy District General Hospital. Between November 2009 to November 2012, 76 patients underwent PFNA. These patients were identified from the local hip fracture database, which is prospectively collected. The mean age of the patients was 80.11 years (range of 26.83 to 98.53). 27 were male and 49 female. Right hip was involved in 36 cases and left hip in 40. 9 patients required revision surgery due to failure of the primary surgery. 2 patients died due to other causes. 5 out of the 9 patients who underwent revision surgery had their primary surgery performed by a trainee under consultant supervision and a consultant surgeon performed the other 4 cases. In our series failure rate was 11.8%. We conclude that although PFNA is an excellent device to fix subtrochanteric or communited intertrochanteric fractures of the proximal femur one needs to be cautious and follow the correct operative technique to avoid failures

In patients requiring two-stage procedures, stabilization of large skeletal defects after radical debridement must be attained in order to successfully treat the infection. With the use of standard rod plus antibiotic impregnated PMMA spacers limb salvage may be attempted with satisfactory results. Between 1992 and 2014, 23 patients were treated for hip, knee, or shoulder musculoskeletal infections resulting in an average skeletal defect of 22 cm. There were 13 males and 10 females. Twelve patients had infected tumor prostheses, seven patients had an infected total joint arthroplasty, and four patients had a primary infection involving a large skeletal defect. The mean time from the index procedure until infection was 22 months. Following debridement, the defect was stabilized with Tobramycin and Vancomycin impregnated PMMA and intramedullary nails. Patients were treated with IV and oral antibiotics for six weeks each. In 18 patients who had resection about the knee stabilization was achieved with a single femoral or tibial nail in nine patients and with two nails joined by a screw or cerclage wire in the other nine. In four patients a cephalomedullary femoral nail was used for stabilization after resection of the proximal or total femur. One patient had a custom total humeral prostalac using threaded Steinmann pins and 16-gauge wire. The organisms cultured were gram positive in 19 cases, mixed gram positive and fungal in one, mixed gram negative and mycobacterium in one, and two patients had no growth on cultures but histologic evidence of acute infection. Of the 23 patients, 16 were successfully reimplanted following the initial procedure (70%) and seven had recurrent infections. Three patients with recurrent infections were successfully reimplanted after an additional one-stage procedure and four patients were not reimplanted. Two of these four had amputations and the other two had a second two-stage procedure and have retained their spacers. There were seven complications including a broken spacer, three periprosthetic fractures, two contractures, and one case of aseptic loosening. Successful limb salvage with infection control was 19/23 (83%). One patient required an amputation for local recurrence of their tumor. The overall limb salvage rate was 18/23 (78%). Stable temporary antibiotic laden cement spacers, made in conjunction with standard intramedullary nails, can provide the necessary limb stability to treat musculoskeletal infections and allow for reimplanation of tumor prostheses for limb salvage

Introduction. The project of a modular, double-conicity stem is born from the need to obtain primary stability and correct osseointegration in patients with developmental hip dysplasia, or proximal femoral dysmorphisms requiring a femoral shortening osteotomy or presenting characteristics of non-adaptability to single-conicity or straight stems. Such an implant could also be employed in femoral nail failures, or lateral femoral neck fractures requiring prosthetic substitution. Aim of the study. To assess implantability of the new double-conicity stem in cadaver femurs, determining “fit and fill” and the behaviour of femoral cortical bone by means of Rx, CT and pre- and post-implantation mechanical testing. Methods. Seven double-conicity stems with anti-rotation fins were implanted in cadaver femurs of various sizes. All femurs underwent pre- and post-implantation radiological assessment for evaluation of fit and fill at the 2 levels corresponding to the 2 conicities, fins penetration, possible microfractures and stem positioning. Prior to implantation, templating was carried out to define the correct size of the stem to be implanted. Modular necks with cervico-diaphyseal angle of 125° or 135° (short or long) were implanted, to preserve the correct rotation center and femoral offset. In 2 femurs, mechanical testing was performed before and after implantation, in order to assess, by means of strain gauges, the variation of the tensional state of cortical bone under dynamic loading (gait cycle simulation). In 2 femurs, 3 cm chevron shortening osteotomies were performed and stabilized with the stem alone. Results. Implanted stems respected pre-operative planning. In the 2 cases in which shortening osteotomies were performed, the stem allowed for good meta-diaphyseal stability without the employment of fixation devices. Radiographic assessment evidenced a valid “fit and fill”. In 4 cases the stem was correctly aligned; in 2 cases it was positioned in 1° varus and in 1 case in 1° valgus. In the 2 osteotomy cases, penetration of the fins was good at the proximal level and slight distally. In the remaining 4 cases penetration at both levels ranged from slight to good. No microfractures, either intraoperative or following stress testing, were evidenced. Mechanical tests showed that stem implantation reduced deformation of the femoral cortical bone undergoing cyclic loading, in comparison with the pre-implantation situation. Conclusions. The double-conicity prosthetic stem showed good implantability, with the capacity to allow for stability in case of femoral shortening osteotomies without the use of plates or cerclage fixation. Mechanical testing also showed a correct load distribution, and a reduction of stress on femoral cortical bone in comparison with the state before implantation. Prospective clinical studies are necessary to assess efficacy and dependability from a clinical and radiographic viewpoint