With greater numbers of younger patients undergoing total hip replacement (THR), the effect of patient age on the diameter of the femoral canal may become more relevant. This study aimed to investigate the relationship between the diameter of the diaphysis of the femoral canal with increasing age in a large number of patients who underwent THR. A total of 1685 patients scheduled for THR had their femoral dimensions recorded from calibrated radiographs. There were 736 males and 949 females with mean ages of 67.1 years (34 to 92) and 70.2 years (29 to 92), respectively. The mean diameter of the femoral canal was 13.3 mm (8.0 to 23.0) for males and 12.7 mm (6.0 to 26.0) for females. There was a poor correlation between age and the diameter of the canal in males (r = 0.071, p = 0.05) but a stronger correlation in females (r = 0.31, p < 0.001). The diameter of the femoral canal diameter of a female patient undergoing THR could be predicted to increase by 3.2 mm between the ages of 40 and 80 years, in contrast a male would be expected to experience only a 0.6 mm increase during the same period. This increase in the diameter of the canal with age might affect the long-term survival of the femoral component in female patients. Cite this article: Bone Joint J 2013;95-B:339–42

The anatomy of the femur shows a high inter-patient variability, making it challenging to design standard prosthetic devices that perfectly adapt to the geometry of each individual. Over the past decade, Statistical Shape Models (SSMs) have been largely used as a tool to represent an average shape of many three-dimensional objects, as well as their variation in shape. However, no studies of the morphology of the residual femoral canal in patients who have undergone an amputation have been performed. The aim of this study was therefore to evaluate the main modes of variation in the shape of the canal, therefore simulating and analysing different levels of osteotomy. To assess the variability of the femoral canal, 72 CT-scans of the lower limb were selected. A segmentation was performed to isolate the region of interest (ROI), ranging from the lesser tip of the trochanter to the 75% of the length of the femur. The canals were then sized to scale, aligned, and 16 osteotomy levels were simulated, starting from a section corresponding to 25% of the ROI and up to the distal section. For each level, the main modes of variations of the femoral canal were identified through Principal Component Analysis (PCA), thus generating the mean geometry and the extreme shapes (±2 stdev) of the principal modes of variation. The shape of the canals obtained from these geometries was reconstructed every 10 mm, best- fitted with an ellipse and the following parameters were evaluated: i) ellipticity, by looking at the difference between axismax and axismin; ii) curvature of the canal, calculating the arc of circumference passing through the shapes’ centroids; iii) conicity, by looking at the maximum/minimum diameter; iv) mean diameter. To understand the association between the main modes and the shape variance, these parameters were compared, for each level of osteotomy, between the two extreme geometries of the main modes of variation. Results from PCA pointed out that the first three PCs explained more than the 87% of the total variance, for each level of simulated osteotomy. By analysing the extreme geometries for a distal osteotomy (e.g. 80% of the length of the canal), the first PC was associated to a combination of ROC (var%=41%), conicity (var%=28%) and ellipticity (var%=7%). PC2 was still associated with the ROC (var%=16%), while PC3 turned out to be associated with the diameter (var%=38%). Through the SSM presented in this study, a quantitatively evaluation of the deformation of the intramedullary canal has been made possible. By analysing the extreme geometries obtained from the first three modes of variance, it is clear that the first three PCs accounted for the variations in terms of curvature, conicity, ellipticity and diameter of the femoral canal with a different weight, depending on the level of osteotomy. Through this work, it was also possible to parametrize these variations according to the level of excision. The results given for the segment corresponding to the 80% of the length of the canal showed that, at that specified level, the ROC, conicity and ellipticity were the anatomical parameters with the highest range of variability, followed by the variation in terms of diameter. Therefore, the analysis carried out can provide information about the relevance of these parameters depending on the level of osteotomy suffered by the amputee. In this way, optimal strategies for the design and/or customization of osteo-integrated stems can be offered depending on the patient's residual limb

We have developed an animal model to examine the formation of heterotopic ossification using standardised muscular damage and implantation of a beta-tricalcium phosphate block into a hip capsulotomy wound in Wistar rats. The aim was to investigate how cells originating from drilled femoral canals and damaged muscles influence the formation of heterotopic bone. The femoral canal was either drilled or left untouched and a tricalcium phosphate block, immersed either in saline or a rhBMP-2 solution, was implanted. These implants were removed at three and 21 days after the operation and examined histologically, histomorphometrically and immunohistochemically. Bone formation was seen in all implants in rhBMP-2-immersed, whereas in those immersed in saline the process was minimal, irrespective of drilling of the femoral canals. Bone mineralisation was somewhat greater in the absence of drilling with a mean mineralised volume to mean total volume of 18.2% (. sd. 4.5) versus 12.7% (. sd. 2.9, p < 0.019), respectively. Our findings suggest that osteoinductive signalling is an early event in the formation of ectopic bone. If applicable to man the results indicate that careful tissue handling is more important than the prevention of the dissemination of bone cells in order to avoid heterotopic ossification

Introduction and Objectives: We analysed a series of 27 patients who underwent salvage total hip replacement and femoral packing with bone bank allograft for the treatment of femoral defects. We analyzed results clinically and radiographically. Materials and Methods: This study involved 27 hip salvage surgeries in 27 patients. The patients were treated between March 1997 and April 1999 with a follow-up period of 4–6 years. Femoral defects were classified according to AAOS criteria. Clinical results were assessed using the Harris scale. Radiographic studies were performed postoperatively, at 6 months, at one year after treatment, at 4 years, and in 6 cases, at 6 years. We also analysed clinical complications, technical problems, and sinking of the prosthesis into the femoral canal. Results: Of these patients, 80% did not present with pain one year after treatment, and 85% could walk without assistance. The graft was incorporated in 90% of cases. Sinking of the prosthesis without indications of loosening occurred in less than 50% of cases. In one patient is was necessary to repeat treatment due to sinking and loosening of the femoral component, and in another case it was necessary to remove the prosthesis due to infection. Discussion and Conclusions: The method of impaction of morselised cancellous bone into the femoral canal as described by Ling et al. has been shown in recent years to be reliable and reproducible in cases of femoral canal defects resulting from osteolysis and significant losses of cortical bone. Bone stock is restored, thus paving the way for future revisions with distal diaphyseal attachment revision prosthesis. Continued evaluation of the allograft impaction technique in femoral component revision shows optimal results after 5 years of follow up

We have long suspected that patients treated at our institution have narrower femoral canals than the literature suggests. This has implications when it comes to nail size and the question of using reamed or unreamed nails. Using CT analysis, we studied the morphology of the femoral isthmus. We prospectively evaluated 30 men with a mean age of 26 years (20 to 35). Patients with previous femoral fractures were excluded from the study. A scanogram determined the level of the isthmus and axial cuts at this level accurately revealed canal size and shape. We found a canal size of less than 12 mm in 62%. In a third of these, canal size was less than 11 mm. Axial cuts showed three types of femoral canals: 14 patients had thick femoral cortices and a narrow canal, seven had thin cortices and a wider canal, and nine had an oval canal, with the larger diameter in the sagittal plane. If one adheres to the principle of reaming until cortical clutter is heard, the recommended 12-mm or 13-mm reamed femoral nail is not suitable for the majority of non-Caucasian men in our population. Larger nails may cause such complications as delayed union, nonunion and fracture. Smaller nails of 10-mm and 11-mm diameter result in satisfactory clinical and radiological outcomes

We have investigated the use of a conically-shaped cement plug made of Polyactive (PA), a biodegradable copolymer. The flexibility and hydrogel properties were thought to facilitate occlusion of the femoral canal even when it was oval or irregular in shape. The function of the plug was first compared with that of the Thackray polyethylene model in 16 artificial plastic femora. The maximum intramedullary pressure achieved during cementing was ten times higher with the biodegradable model. Migration or leakage of cement did not occur when the diameter of the femoral canal was equal to or smaller than the diameter of the plug. We also showed that the biodegradable properties of this implant were such that it did not require removal during revision. The new plug was tested in a pilot clinical trial. At two years only two out of 21 patients had evidence of migration or leakage of cement, probably due to a mismatch in the size of plug and femoral canal. There were no local changes in the femur

Bone growth was compared in six types of (beta-tricalcium phosphate) implants implanted in subcutaneous pouches or close to femoral head of male Wistar rats:. implants immersed in 0.9% sodium chloride solution (control implants),. implants with the progenitor cells from femoral canal,. implants immersed in inductive BMP-2 solution,. implants with the progenitor cells from femoral canal + BMP-2 solution,. implants immersed in inductive BMP-2 solution and implanted closed to the femoral head,. implants immersed in inductive BMP-2 solution and implanted closed to the femoral head while leaving the femoral canal opened for better access of the femoral canal cells. Implants were removed 21 days after operation and dissected following principles of stereology. Presence of bone or cartilage or connective tissue was evaluated by hematoxylin eosin histochemistry. Results: Bone formation was only found in the implants where BMP-2 was introduced. However, no distinctive differences were found between the implants where cells and BMP-2 were introduced and between the implants where just BMP-2 was used. Percentages of the bone tissue out of all the implant were as follows: 0.0% in group 1, 1.2% in group 2, 32.4% in group 3, 42.4% in group 4, 44.4% in group 5 and, 54.9% in group 6. Differences in amount of bone tissue were statistically significant between groups 3 and 2, groups 3 and 1 and also between groups 1 and 2 (p=0.0013, p=0.0004 and p=0.0525 respectively). In the other cases, the differences between BMP-2 affected implants and implants without BMP-2 were even greater. We concluded that presence of osteoconductive matrix and introduction of an osteoinductive agent (e.g. BMP-2) are the main components of designing of bone tissue and introduction of exogenous bone cells is not as important as the first two in subcutaneous pouches or close to the hip joint

In the cementless total hip arthroplasty, the position of the stem is pretty much determined by broach and rasping with which the is required for two reasons: one is to align the stem with the femur at the desired position and the orientation. The other is to achieve the conformity between the stem and the prepared proximal cavity surface in the femur. The robotic hip surgery can be a solution for the accurate of femoral canal shaping, but recent reports about the clinical follow-up study of the robotic hip surgery indicated frequent dislocation mainly due to the excessive soft tissue damage during robotic operation. In this paper, a guide being inserted into the femoral canal is proposed to restrict the undesired motion of the rasp inside the femur without extra incision. A set of canal guide and custom rasp for the selected stem(versys fibermetal midcoat, zimmer co.)were developed and tested with 4 synthetic femurs (model 1130, Sawbones co.). After rasping, a plastic copy of the stem was inserted into the femur and sliced at 5 mm thickness. From obtained cross sections, percentages of the gap larger than 0.3mm between the stem and the bone was measured. 6_C_Results: In average, 79% of bone-implant interface was close contact. Valgus/varus deviations of the stem were 0.40±0.45 degree, which means the angle of axis of straight reamer and axis of final cut. In average, 79% of bone-implant interface was close contact. Valgus/varus deviations of the stem were 0.40±0.45 degree, which means the angle of axis of straight reamer and axis of final cut. The conformity of femoral canal with the femoral stem in this approach was higher than the conventional hip surgery and comparable to those in the robotic surgery. The alignment of the stem within the femur is also as good as those in the robotic surgery(0.34±0.67 approach does require neither expensive system nor CT scan. Also this approach can be executed swiftly without extra time and unnecessary large incision compared with the robotic surgery

Objectives. In total hip arthroplasty (THA), the cementless, tapered-wedge stem design contributes to achieving initial stability and providing optimal load transfer in the proximal femur. However, loading conditions on the femur following THA are also influenced by femoral structure. Therefore, we determined the effects of tapered-wedge stems on the load distribution of the femur using subject-specific finite element models of femurs with various canal shapes. Patients and Methods. We studied 20 femurs, including seven champagne flute-type femurs, five stovepipe-type femurs, and eight intermediate-type femurs, in patients who had undergone cementless THA using the Accolade TMZF stem at our institution. Subject–specific finite element (FE) models of pre- and post-operative femurs with stems were constructed and used to perform FE analyses (FEAs) to simulate single-leg stance. FEA predictions were compared with changes in bone mineral density (BMD) measured for each patient during the first post-operative year. Results. Stovepipe models implanted with large-size stems had significantly lower equivalent stress on the proximal-medial area of the femur compared with champagne-flute and intermediate models, with a significant loss of BMD in the corresponding area at one year post-operatively. Conclusions. The stovepipe femurs required a large-size stem to obtain an optimal fit of the stem. The FEA result and post-operative BMD change of the femur suggest that the combination of a large-size Accolade TMZF stem and stovepipe femur may be associated with proximal stress shielding. Cite this article: M. Oba, Y. Inaba, N. Kobayashi, H. Ike, T. Tezuka, T. Saito. Effect of femoral canal shape on mechanical stress distribution and adaptive bone remodelling around a cementless tapered-wedge stem. Bone Joint Res 2016;5:362–369. DOI: 10.1302/2046-3758.59.2000525

For radiographic assessment of THA, we must estimate a 3-D structure with 2-D images. Basically, it has been good. But even after a successful surgery, sometimes we encountered an undersized stem in radiograph. Interestingly, it was more frequent after we introduced surgical robot for primary THA. It sometimes brought a huge dilemma during planning and evaluating the surgery. We performed this study to elucidate the cause of this problem. We used image data of 30 consecutive THAs using ROBODOC (ISS, USA). The measurement was made with the built-in tool in the Orthodoc, which is for the CT-based preoperative planning, and digital imaging system (PiView, Infinitt, Korea). We measured femoral anteversion, tilting angle at corresponding level, the longest and shortest diameters of femoral canal and their ratio. Also we measured anteversion and alignment of the stem. The canal filling of the stem was measured in projected images with CT and postoperative radiographs. The mean femoral anteversion was 21.1±10.2°. The canal tiling angle was 39.3±7.9°(p< 0.01). The long and short diameters were 19.3±2.6° and 14.3±1.8°. The mean ratio between them was 0.8±0.08°. Canal filling at AP and lateral dimensions were 88.25±9.8% and 85.7±6.9%. In postoperative radiographs, they were 85.4±7.3%(p=0.05) and 88.0±6.1%(p=0.06). This result suggests that the femoral canal at this particular or more distal level is elliptically shaped constantly. It tilts (in axial plane) to the same direction but not to the same degrees with femoral anteversion. Because of this tilt, relatively well-fixed round femoral stem can be considered as undersized in plane radiograph. Therefore, rather than using two plain radiographs alone for postoperative evaluation, adding postoperative CT may provide appropriate accuracy for assessment. And surgeon should keep in mind this axial tilt during planning and evaluating a robotic THA, especially not to remove too much healthy cortical bones to obtain full distal filling

Introduction

To utilize existing cancellous bone for initial stability, custom-made stems were implanted without reaming and rasping. This study reviewed the results of this non-reaming technique.

Introduction

One of the objectives of total hip arthroplasty is to restore femoral and acetabular combined anteversion. It is desirable to reproduce both femoral and acetabular antevesions to maximize the acetabular cup fixation coverage and hip joint stability. Studies investigated the resultant of implanted femoral stem anteversion in western populations showed that the implanted femoral stems had only a small portion can meet the desirable femoral anteversion angle¹, and anteversion angle increases after the implantation of an anatomical femoral stem with anteverted stem neck comparing to anatomical femoral neck². The purpose of this study was to anatomically measure the anteversion angular difference between metaphyseal long axis and femoral neck in normal Chinese population. The metaphyseal long axis represents the coronal fixation plane of modern cementless medial-lateral cortical fitting taper stem. This angular difference or torsion Δ angle provides the estimation of how much the neck antevertion angle of femoral stem would be needed to match for desirable anatomical femoral neck version.

Introduction. Traditionally, conventional radiographs of the hip are used to assist surgeons during the preoperative planning process, and these processes generally involve two-dimensional X-ray images with implant templates. Unfortunately, while this technique has been used for many years, it is very manual and can lead to inaccurate fits, such as “good” fits in the frontal view but misalignment in the sagittal view. In order to overcome such shortcomings, it is necessary to fully describe the morphology of the femur in three dimensions, therefore allowing the surgeon to successfully view and fit the components from all possible angles. Objective. The objective of this study was to efficiently describe the morphology of the proximal femur based on existing anatomical landmarks for use in surgical planning and/or forward solution modeling. Methods. Seven parameters are needed to fully define femoral morphology: head diameter, head center, neck shaft axis, femoral canal, proximal shaft axis, offset, and neck shaft angle. A previous algorithm has been developed in-house to automatically locate anatomical landmarks of patient specific bone models. Once the bone model has been aligned and scaled based on these landmarks, the femoral head diameter and center are calculated by iteratively fitting a sphere to the corresponding femoral head point cloud. An iterative cylindrical fitting algorithm is used to describe the neck shaft axis. The femoral canal is determined using three steps: 1) the femur is sliced at 10mm increments below the lesser trochanter, 2) the femoral canal boundary is determined at each slice, and 3) the largest circle is fit within each slice's canal boundary. The proximal shaft axis is described by fitting a line to the canal circle center locations. Offset is defined as the distance from the head center to the proximal shaft axis. Finally, the neck shaft angle is the angle between the neck shaft axis and the proximal shaft axis. Results. The goal pertaining to femoral component morphology is to provide meaningful information that can be used to determine how the femoral stem fits within the canal. Regardless of differences in bone sizes and geometries, the algorithm has proven to be successful in describing the femoral morphology of a patient-specific bone model. Discussion. These results lay the groundwork for an automatic stem fitting algorithm, which is described in a subsequent abstract. The morphology knowledge of the femoral head, femoral neck, femoral canal, and various axes can be coupled with known THA component parameters (such as offset, neck length, neck shaft angle, etc.) to allow our algorithms to predict the “best selection” and “best fit” for the femoral stem. This can also be applied to the acetabulum and can then be used as a surgical planning tool as well as a parameter when modeling postoperative predictions. For any figures or tables, please contact authors directly

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

The number of cemented femoral stems implanted in the United States continues to slowly decrease over time. Approximately 10% of all femoral components implanted today are cemented, and the majority are in patients undergoing hip arthroplasty for femoral neck fractures. The European experience is quite different. In the UK, cemented femoral stems account for approximately 50% of all implants, while in the Swedish registry, cemented stems still account for the majority of implanted femoral components. Recent data demonstrating some limitations of uncemented fixation in the elderly for primary THA, may suggest that a cemented femoral component may be an attractive alternative in such a group. Two general philosophies exist with regards to the cemented femoral stem: Taper slip and Composite Beam. There are flagship implants representing both philosophies and select designs have shown excellent results past 30 years. A good femoral component design and cementing technique, however, is crucial for long-term clinical success. The author's personal preference is that of a “taper slip” design. The cemented Exeter stem has shown excellent results past 30 years with rare cases of loosening. The characteristic behavior of such a stem is to allow slight subsidence of the stem within the cement mantle through the process of cement creep. One or two millimeters of subsidence in the long-term have been observed with no detrimental clinical consequences. There have been ample results in the literature showing the excellent results at mid- and long-term in all patient groups. The author's current indication for a cemented stem include the elderly with no clear and definitive cutoff for age, most likely in females, THA for femoral neck fracture, small femoral canals such as those patients with DDH, and occasionally in patients with history of previous hip infection. Modern and impeccable cement technique is paramount for durable cemented fixation. It is important to remember that the goal is interdigitation of the cement with cancellous bone, so preparing the femur should not remove cancellous bone. Modern technique includes distal plugging of the femoral canal, pulsatile lavage, drying of the femoral canal with epinephrine or hydrogen peroxide, retrograde fill of the femoral canal with cement with appropriate suction and pressurization of the femoral cement into the canal prior to implantation of the femoral component. The dreaded “cement implantation syndrome” leading to sudden death can be avoided by appropriate fluid resuscitation prior to implanting the femoral component. This is an extremely rare occurrence today with reported mortality for the Exeter stem of 1 in 10,000. A cemented femoral component has been shown to be clinically successful at long term. Unfortunately, the art of cementing a femoral component has been lost and is rarely performed in the US. The number of cemented stems, unfortunately, may continue to go down as it is uncommonly taught in residency and fellowship, however, it might find a resurgence as the limits of uncemented fixation in the elderly are encountered. National joint registers support the use of cemented femoral components, and actually demonstrate higher survivorship at short term when compared to all other uncemented femoral components. A cemented femoral component should be in the hip surgeons armamentarium when treating patients undergoing primary and revision THA

Traditional mechanical debridement can only remove visibly infected tissue and is unable to completely clear all the biofilm that hides within muscle crevices and nerves. This study aims to determine the results of single-stage revision using noncontact low frequency ultrasonic debridement in treating chronic periprosthetic joint infections (PJI). A prospective study of consecutive patients requiring single-stage revision for chronic PJI was performed since August 2021. After mechanical debridement, an 8‑mm handheld non‑contact low‑frequency ultrasound probe was used for ultrasonic debridement at a frequency of (25±5) kHz and power of 90% for 5 minutes. Each ultrasound lasted 10 seconds with 3‑seconds intervals. The probe was repeatedly sonicated among all soft tissue and bsingle interface. The distal femoral canal and the posterior capsule of the knee were fully sonicated with a special right‑angle probe. Chemical debridement was then performed to irrigation the whole operative area. Recurrence of infection, culture results and number of colonies 24 hours after ultrasonic debridement were recorded. A total of 45 patients (25 hips and 20 knees) were included and 43 of them (95.6%) were free of infection at a mean follow-up time of 29 months (24 to 33). There were no intraoperative complications related to ultrasonic debridement (neurovascular and muscle injury, poor wound healing and fat liquefaction). The culture‑positive rate of wound liquid before ultrasonic debridement was 40.0% (18/45), which significantly increased to 75.6% (34/45) after ultrasonic debridement (P=0.001). The median number of colonies 24 hours after ultrasonic debridement was 2372 CFU/ml (310 to 4340 CFU/ml), which was significantly higher than that before debridement (307 CFU/ml; 10 to 980 CFU/ml) (P=0.000). Single-stage revision with non‑contact low‑frequency ultrasonic debridement can fully expose bacteria within biofilm, increase the efficacy of chemical debridement and lead to a favorable short‑term outcome without related complications

Although data on uncemented short stems are available, studies on cemented short-stemmed THAs are limited. These cemented short stems may have inferior long-term outcomes and higher femoral component fracture rates. Hence, we examined the long-term follow-up of cemented short Exeter stems used in primary THA. Within the Exeter stem range, 7 stems have a stem length of 125 mm or less. These stems are often used in small patients, in young patients with a narrow femoral canal or patients with anatomical abnormalities. Based on our local database, we included 394 consecutive cemented stems used in primary THA (n=333 patients) with a stem length ≤125 mm implanted in our tertiary referral center between 1993 and December 2021. We used the Dutch Arthroplasty Registry (LROI) to complete and cross-check the data. Kaplan-Meier survival analyses were performed to determine 20-year survival rates with stem revision for any reason, for septic loosening, for aseptic loosening and for femoral component fracture as endpoints. The proportion of male patients was 21% (n=83). Median age at surgery was 42 years (interquartile range: 30–55). The main indication for primary THA was childhood hip diseases (51%). The 20-year stem survival rate of the short stem was 85.4% (95% CI: 73.9–92.0) for revision for any reason and 96.2% (95%CI: 90.5–98.5) for revision for septic loosening. No stems were revised for aseptic femoral loosening. However, there were 4 stem fractures at 6.6, 11.6, 16.5 and 18.2 years of follow-up. The stem survival with femoral component fracture as endpoint was 92.7% (CI: 78.5–97.6) at 20 years. Cemented short Exeter stems in primary THA show acceptable survival rates at long-term follow-up. Although femoral component fracture is a rare complication of a cemented short Exeter stem, orthopaedic surgeons should be aware of its incidence and possible risk factors

Intraoperative fractures although rare are one of the complications known to occur while performing a total hip arthroplasty (THA). However, due to lower incidence rates there is currently a gap in this area of literature that systematically reviews this important issue of complications associated with THA. Method: We looked into Electronic databases including PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), the archives of meetings of orthopaedic associations and the bibliographies of included articles and asked experts to identify prospective studies, published in any language that evaluated intra-operative fractures occurring during total hip arthroplasty from the year 1950-2020. The screening, data extraction and quality assessment were carried out by two researchers and if there was any discrepancy, a third reviewer was involved. Fourteen studies were identified. The reported range of occurrence of fracture while performing hip replacement surgery was found to be 0.4-7.6%. Major risk factors identified were surgical approaches, Elderly age, less Metaphyseal-Diaphyseal Index score, change in resistance while insertion of the femur implants, inexperienced surgeons, uncemented femoral components, use of monoblock elliptical components, implantation of the acetabular components, patients with ankylosing spondylitis, female gender, uncemented stems in patients with abnormal proximal femoral anatomy and with cortices, different stem designs, heterogeneous fracture patterns and toothed design. Intraoperative fractures during THA were managed with cerclage wire, femoral revision, intramedullary nail and cerclage wires, use of internal fixation plates and screws for management of intra operative femur and acetabular fractures. The main reason for intraoperative fracture was found to be usage of cementless implants but planning and timely recognition of risk factors and evaluating them is important in management of intraoperative fractures. Adequate surgical site exposure is critical especially during dislocation of hip, reaming of acetabulum, impaction of implant and preparing the femoral canal for stem insertion. Eccentric and increased reaming of acetabulum to accommodate a larger cup is to be avoided, especially in females and elderly patients as the acetabulum is thinner. However, this area requires more research in order to obtain more evidence on effectiveness, safety and management of intraoperative fractures during THA

Introduction. Since the expanded war in Ukraine in 2022, explosives, mines, debris, blast waves, and other factors have predominantly caused injuries during artillery or rocket attacks. These injuries, such as those from shelling shrapnel, involve high-energy penetrating agents, resulting in extensive necrosis and notable characteristics like soft tissue defects and multiple fragmentary fractures with bone tissue defects and a high rate of infection complications caused by multi resistant gram-negative (MRGN) pathogens. Material and Methods. We conducted a prospective study at our center between March 2022 and December 2023. Out of the 56 patients from Ukraine, 21 met the inclusion criteria who had severe war injuries were included in the study. Each of these patients presented with multiple injuries to both bones and soft tissues, having initially undergone treatment in Ukraine involving multiple surgeries. The diagnosis of infection was established based on the EBJIS criteria. Prior to our treatment patients had undergone multiple revision surgeries, including debridement, biopsies, implant and fixator replacement. Additionally, soft tissue management required previously VAC therapy and flap reconstruction for successful treatment. Results. All 21 infections manifested as bone infections (11; 52%), followed by implant-associated infections (5; 24%), soft tissue infections (4; 19%), and septic arthritis (1; 5%). In all patients, the infection was polymicrobial, caused by 3- and 4-MRGN pathogens, as Klebsiella pneumonia 4MRGN, Proteus mirabilis 4MRGN, Enterobacter cloacae 4MRGN etc. Upon admission, all patients carried a diagnosis and exhibited signs indicative of chronic infection. 19 (90.5%) patients required complex antibiotic regimens combined with multiple wound revisions and debridements, changes of fixators and combination of systemic and local antibiotic therapy. In 6 patients (28%) high dosages of local antibiotics such as gentamycin, vancomycin and meropenem were incorporated into a carrier of bio-absorbable calcium sulfate, calcium sulfate/hydroxyapatite which were introduced into the hip joint, femoral canal or bone defect for dead space management during the surgery. When local antibiotics were administered at intervals, the microbiology results at implantation showed negative results. 2 (9%) patients had new infections (different site, different pathogens), 1 (4.8%) is still under the treatment. In 17 (81%) patients infection complications were treated successfully with no recurrence of infection. Conclusion. War injuries result in complex bone and soft-tissue infections caused by 3-, 4-MRGN pathogens. Addressing this challenge necessitates multidisciplinary approach with multiple, thorough surgical debridements, effective local, and systemic antimicrobial therapy. As for the outlook we can see potential in local antibiotic carriers

The number of cemented femoral stems implanted in the United States continues to slowly decrease over time. Approximately 10% of all femoral components implanted today are cemented, and the majority are in patients undergoing hip arthroplasty for femoral neck fractures. The European experience is quite different, in the UK, cemented femoral stems account for approximately 50% of all implants, while in the Swedish registry, cemented stems still account for the majority of implanted femoral components. Recent data demonstrating some limitations of uncemented fixation in the elderly for primary THA, may suggest that a cemented femoral component may be an attractive alternative in such a group. Two general philosophies exist with regards to the cemented femoral stem: Taper slip and Composite Beam. There are flagship implants representing both philosophies and select designs have shown excellent results past 30 years. A good femoral component design and cementing technique, however, is crucial for long-term clinical success. The authors' personal preference is that of a “taper slip” design. The cemented Exeter stem has shown excellent results past 30 years with rare cases of loosening. The characteristic behavior of such a stem is to allow slight subsidence of the stem within the cement mantle through the process of cement creep. One or two millimeters of subsidence in the long-term have been observed with no detrimental clinical consequences. There have been ample results in the literature showing the excellent results at mid- and long-term in all patient groups. The authors' current indications for a cemented stem include the elderly with no clear and definitive cutoff for age, most likely in females, THA for femoral neck fracture, small femoral canals such as those patients with DDH, and occasionally in patients with history of previous hip infection. Modern and impeccable cement technique is paramount for durable cemented fixation. It is important to remember that the goal is interdigitation of the cement with cancellous bone, so preparing the femur should not remove cancellous bone. Modern technique includes distal plugging of the femoral canal, pulsatile lavage, drying of the femoral canal with epinephrine or hydrogen peroxide, retrograde fill of the femoral canal with cement with appropriate suction and pressurization of the femoral cement into the canal prior to implantation of the femoral component. The dreaded “cement implantation syndrome” leading to sudden death can be avoided by appropriate fluid resuscitation prior to implanting the femoral component. This is a extremely rare occurrence today with reported mortality for the Exeter stem of 1 in 10,000. A cemented femoral component has been shown to be clinically successful at long term. Unfortunately, the art of cementing a femoral component has been lost and is rarely performed in the US. The number of cemented stems unfortunately may continue to go down as it is uncommonly taught in residency and fellowship, however it might find a resurgence as the limits of uncemented fixation in the elderly are encountered. National joint registers support the use of cemented femoral components, and actually demonstrate higher survivorship at short term when compared to all other uncemented femoral components. A cemented femoral component should be in the hip surgeons' armamentarium when treating patients undergoing primary and revision THA