With the advent of digital radiology, our institution has introduced digital templating for preoperative planning of total hip arthroplasty (THA). Prior studies of the accuracy of digital templating had contradictory results. This study compares the accuracy of digital and analog templating for THA. Ninety patients were recruited. Sixty-eight patients had analog pre-operative templating while 22 patients had digital templating. A retrospective review of medical records obtained the sizes of hip implants inserted during THA and patient demographics. The templated hip sizes were compared with the actual hip implants inserted. Accuracies of both templating methods were compared in four outcomes: prediction of acetabular cup size, prediction of femoral stem size, prediction of femoral offset and prediction of femoral neck length.

Digital templating was more accurate than analog templating in predicting acetabular cup size, femoral stem size and femoral offset. Analog templating was more accurate in predicting femoral neck length. However, only the comparison of femoral offset achieved statistical significance (p-value = 0.049).

After stratifying the data by BMI, digital templating was more accurate than analog templating in predicting acetabular cup and femoral stem sizes for patients with high BMI. For patients with BMI = 25-30, accuracy of digital templating was 100.0% for cup and 80.0% for stem while accuracy of analog templating was 74.1% for cup and 74.1% for stem. For patients with BMI > 30, accuracy of digital templating was 84.6% for cup and 69.2% for stem while that of analog templating was 75.0% for cup and 66.7% for stem.

Digital templating outperformed analog templating in all the outcomes except femoral neck length. In addition, digital templating was significantly more accurate in predicting femoral offset. This study showed that digital templating has the potential to reduce errors in pre-operative planning for THA.

Introduction. Robotics have been applied to total knee arthroplasty (TKA) to improve surgical precision in component placement and joint function restoration. The purpose of this study was to evaluate prosthetic component alignment in robotic arm-assisted (RA)-TKA performed with functional alignment and intraoperative fine-tuning, aiming for symmetric medial and lateral gaps in flexion/extension. It was hypothesized that functionally aligned RA-TKA the femoral and tibial cuts would be performed in line with the preoperative joint line orientation. Methods. Between September 2018 and January 2020, 81 RA cruciate retaining (CR) and posterior stabilized (PS) TKAs were performed at a single center. Preoperative radiographs were obtained, and measures were performed according to Paley's. Preoperatively, cuts were planned based on radiographic epiphyseal anatomies and respecting ±3° boundaries from neutral coronal alignment. Intraoperatively, the tibial and femoral cuts were modified based on the individual soft tissue-guided fine-tuning, aiming for symmetric medial and lateral gaps in flexion/extension. Robotic data were recorded. Results. A total of 56 RA-TKAs performed on varus knees were taken into account. On average, the tibial component was placed at 1.9° varus (SD 0.7) and 3.3° (SD 1.0) in the coronal and sagittal planes, respectively. The average femoral component alignment, based on the soft tissue tensioning with spoons, resulted as follows: 0.7° varus (SD 1.7) in the coronal plane and 1.8° (SD 2.1) of external rotation relative to surgical transepicondylar axis in the transverse plane. A statistically significant linear direct relationship was demonstrated between radiographic epiphyseal femoral and tibial coronal alignment and femoral (r=0.3, p<0.05) and tibial (r=0.3, p<0.01) coronal cuts, resepctively. Conclusion. Functionally aligned RA-TKA performed in varus knees, aiming for ligaments’ preservation and balanced flexion/extension gaps, provided joint line respecting femoral and tibial cuts on the coronal plane

Introduction. Prosthetic replacement remains the treatment of choice for displaced femoral neck fractures in the elderly population, with recent literature demonstrating significant functional benefits of total hip arthroplasty (THA) over hemiarthroplasty. Yet the fracture population also has historically high rates of early postoperative instability when treated with THA. The direct anterior approach (DAA) may offer the potential to decrease the risk of postoperative instability in this high-risk population by maintaining posterior anatomic structures. The addition of intraoperative fluoroscopy can improve precision in component placement and overcome limitations on preoperative planning due to poor preoperative radiographs performed in the emergency setting. Methods. We retrospectively reviewed clinical and radiographic outcomes of 113 consecutive patients with displaced femoral neck fractures treated by two surgeons over a five-year period. All underwent surgery via the DAA using fluoroscopic guidance, and were allowed immediate postoperative weight bearing without any hip precautions or restrictions. Charts were reviewed for relevant complications, while radiographs were reviewed for component positioning, sizing, and leg length discrepancy. Mean follow-up was 8.9 months. Results. Mean age was 79.3 years (range, 42 to 101), 73% of patients were women, and mean BMI was 22.6 kg/m. 2. Ninety patients (80%) received THA while 23 (20%) received unipolar or bipolar hemiarthroplasty. Mean acetabular anteversion was 15.0 degrees (range, 4 to 24) and mean abduction was 39.2 degrees (range, 27 to 51) with 95% of acetabular components in the combined safe zone as described by Lewinnek. Mean radiographic leg-length difference was +2.2 mm (range, −4.9 to +8.8mm). There was no femoral stem subsidence of more than 2mm. Only one patient (0.9%) dislocated postoperatively, who was eventually constrained for recurrent posterior instability 3 months following surgery. Delayed wound healing (6.1%) was the most common postoperative complication. Conclusions. The direct anterior approach allows a safe, effective, and reproducible approach for treatment of displaced femoral neck fractures, with very low rate of early postoperative instability compared to historical controls. The use of intraoperative fluoroscopy allows excellent component positioning, sizing, and restoration of leg length in spite of inconsistent preoperative radiographs

Internal fixation is currently the standard of care for Garden I and II femoral neck fractures in the elderly. However, there may be a degree of posterior tilt on the preoperative lateral radiograph above which failure is likely, and primary arthroplasty would be preferred. The purpose of this study was to determine the association between posterior tilt and the risk of subsequent arthroplasty following internal fixation of Garden I and II femoral neck fractures in the elderly. This study represents a secondary analysis of data collected in the FAITH trial, an international multicenter randomized controlled trial comparing the sliding hip screw to cannulated screws in the management of femoral neck fractures in patients aged 50 years or older. For each patient who sustained a Garden I or II femoral neck fracture and had an adequate preoperative lateral radiograph, the amount of posterior tilt was categorized as < 2 0 degrees or ≥20 degrees. Multivariable Cox proportional hazards analysis was used to assess the association between posterior tilt and subsequent arthroplasty during the two-year follow-up period, while controlling for potential confounders. Of the 555 patients in the study sample, posterior tilt was classified as ≥20 degrees for 67 (12.1%) and < 2 0 degrees for 488 (87.9%). Overall, 13.2% (73/555) of patients underwent subsequent arthroplasty in the 24-month follow-up period. In the multivariable analysis, patients with posterior tilt ≥20 degrees had a significantly increased risk of subsequent arthroplasty compared to those with posterior tilt < 2 0 degrees (22.4% (15/67) vs 11.9% (58/488), Hazard Ratio (HR) 2.22, 95% confidence interval (CI) 1.24–4, p=0.008). The other factor associated with subsequent arthroplasty was age ≥80 (p=0.03). In this study of patients with Garden I and II femoral neck fractures, posterior tilt ≥20 degrees was associated with a significantly increased risk of subsequent arthroplasty. Primary arthroplasty should be considered for Garden I and II femoral neck fractures with posterior tilt ≥20 degrees, especially among older patients

Purpose. Isolated fractures of femoral condyle in the coronal plane (Hoffa fracture) is rare and is surgically challenging to treat. 44 patients were operated between 2004–2014. The aim was to retrospectively assess the fracture patterns, fixation done and functional outcome. Methods. All injuries resulted from direct trauma to the knee out of which 36 were due to road traffic accidents.38 were closed injuries and the rest open.35 involved lateral condyle, 8 involved medial condyle and one was bicondylar type. All were anatomically reduced with fixation decided based on preoperative radiographs, CT scan and intra-op observation. Early passive motion and isometric exercises were started but kept non-weight bearing for 6–8 weeks. The mean follow up period was five years. Outcomes were measured using Neer's scoring system and International Knee Society Documentation Committee (IKDC) Functional Score. Results. 26 patients had excellent outcome, 14 had satisfactory and 4 had unsatisfactory outcome which corresponded with the specified fracture severity pattern. Uniformly excellent results were obtained in all simple pattern fractures, whereas comminuted fracture patterns were more challenging to treat with variable outcomes. Conclusion. In our retrospective observational study, we found that each fracture had specific pattern which dictated the treatment plan and the prognosis. Subsequently we grouped the fractures and proposed a classification system that would specify the pattern of fracture and dictate the type of fixation preferred. We conclude that therapeutic outcome is significantly affected by the amount of articular surface comminution, posterior cortex comminution, attainment of anatomical reduction and stable fixation

Introduction. Conventional hip radiographs allow surgeons, during preoperative planning, to make important decisions. Size and location of implants are routinely measured by overlaying schematics of the implanted components onto preoperative radiographs. Most currently available planning tools are in two-dimensions (2D), using X-ray images and 2D templates of the implants. Determination of the ideal component size requires two radiographic views of the femur: the anterior-posterior (AP) and the lateral direction. The surgeon uses this information to determine component sizes. Even though this approach has been used for many years leading to very good results, this manual process potentially carries multiple shortcomings. The biggest issue with the AP X-ray image is the fact that it is 2D in nature while the measurement's objective is to obtain three-dimensional (3D) parameters. Objective. The objective of this study is to derive a methodology to automatically select correct THA implant sizes while keeping the anatomical center of each specific patient within a forward solution model (FSM) that predicts post-operative outcomes. Methods. The femoral components in our process contain five parameters: stem length, neck offset, neck length, neck shaft angle, and component width. There are many steps to measure the morphologic parameters of a femoral component. (1)Preparation of training implant database, (2)defining multi-plane intersection, (3)determining circumcircles for all intersected femoral component contours, (4)finding centers and radii of circumcircles, (5)measuring distances from each circumcircle to the femoral component head center, and (6)determining the stem shaft axis. The FSM fits specific femoral canal using a 3D mesh model of the femur. The femoral component and canal morphology of a femur model are compared to the training femoral component database. For each femoral component morphology, the algorithm determines how far distally the femoral component fits within the canal before collision between the stem and cortical bone. Once the defined position is confirmed, the relative distance from the anatomical femoral head center to the femoral component head center is calculated. This process is repeated for all femoral component morphology. The best fitting femoral component is determined when the distance from its head center to the femoral head center is minimized, Figure 1. Results. Three intensive validation tools have been developed: (1) cross-sectional analysis, (2) slice analysis, and (3) contact map analysis. Cross-sectional analysis is a graphic interaction program where users can freely view the anatomy at any orientation, Figure 2. The slice analysis enhances the user visualization by providing a static view of the fit between chosen femoral component and femoral canal, Figure 3. Finally, the contact map analysis allows for visualization of contact area through the bone-stem interface. Conclusion and Discussion. This is a powerful tool with the FSM that allows surgeons to get a “best fit” implant in 3D, based on canal fit and distance from anatomical femoral head center. Surgeons may want to manually size up or down, but the program will pick best fit sizes based on anatomical morphology. Future iterations will consider the reaming depth each surgeon uses to improve implant selection for each surgeon's technique. For any figures or tables, please contact authors directly

Introduction. In total knee arthroplasty (TKA), component realignment with bone-based surgical correction (BBSC) can provide soft tissue balance and avoid the unpredictability of soft tissue releases (STR) and potential for more post-operative pain. Robotic-assisted TKA enhances the ability to accurately control bone resection and implant position. The purpose of this study was to identify preoperative and intraoperative predictors for soft tissue release where maximum use of component realignment was desired. Methods. This was a retrospective, single center study comparing 125 robotic-assisted TKAs quantitatively balanced using load-sensing tibial trial components with BBSC and/or STR. A surgical algorithm favoring BBSC with a desired final mechanical alignment of between 3° varus and 2° valgus was utilized. Component realignment adjustments were made during preoperative planning, after varus/valgus stress gaps were assessed after removal of medial and lateral osteophytes (pose capture), and after trialing. STR was performed when a BBSC would not result in knee balance within acceptable alignment parameters. The predictability for STR was assessed at four steps of the procedure: Preoperatively with radiographic analysis, and after assessing static alignment after medial and lateral osteophyte removal, pose capture, and trialing. Cutoff values predictive of release were obtained using receiver operative curve analysis. Results. STR was necessary in 43.5% of cases with medial collateral ligament (MCL) release being the most common. On preoperative radiographs, a medial tibiofemoral angle (mTFA) ≤177° predicted MCL release (AUC = 0.76. p< 0.01) while an mTFA ≥188° predicted ITB release (AUC = 0.79, p <0.01). Intraoperatively after removal of osteophytes, a robotically assessed mechanical alignment (MA) ≥8° varus predicted MCL release (AUC = 0.84. p< 0.01) while a MA ≥2° valgus (AUC = 0.89, p< 0.01) predicted ITB release. During pose-capture, in medially tight knees, an extension gap imbalance ≥2.5mm (AUC = 0.82, p <0.01) and a flexion gap imbalance ≥2.0mm (AUC = 0.78, p <0.01) predicted MCL release while in laterally tight knees, any extension or flexion gap imbalance >0 mm predicted ITB release (AUC = 0.84, p <0.01 and AUC = 0.82, p <0.01 respectively). During trialing, in medially tight knees, a medial>lateral extension load imbalance ≥18 PSI (AUC = 0.84. p< 0.01) and a flexion load imbalance ≥ 35 PSI (AUC = 0.83, p< 0.01) predicted MCL release while, in laterally tight knees, a lateral>medial extension load imbalance ≥3 PSI (AUC = 0.97, p< 0.01) or flexion load imbalance ≥ 9.5 PSI (AUC = 0.86, p< 0.01) predicted ITB release. Of all identified predictors, load imbalance at trialing had the greatest positive predictive value for STR. Conclusion. There are limitations to the extent that TKA imbalance that can be corrected with BBSC alone if one has a range of acceptable alignment parameters. The ability to predict STR improves from pose-capture to trialing stages during detection of load imbalance. Perhaps this may be due to posterior osteophytes that are still present at pose capture. Further investigation of the relationship between the presence, location and size of posterior osteophytes and need for STR during TKA is necessary

Introduction. Today, Uganda has the second highest rate of road accidents in Africa and the world after Ethiopia. According to the World Health Organization's Global Status Report on Road Safety 2013, Uganda is named among countries with alarmingly high road accident rates. If such trend of traffic accidents continues to increase, the health losses from traffic injuries may be ranked as the second to HIV/AIDS by 2020. These road traffic accidents often result in terrible open injuries. Open fractures are complex injuries of bone and soft tissue. They are orthopedic emergencies due to risk of infection secondary to contamination and compromised soft tissues and sometimes vascular supply and associated healing problems. Any wound occurring on the same limb should be suspected as result of open fracture until proven otherwise. The principles of management of open fracture are initial evaluation and exclusion of life threatening injuries, prevention of infection, healing of fracture and restoration of function to injured extremity. Because of the poor hygienic circumstances and the high rate of cross-infection due to the crowded patient-wards, the risk of getting a post-operative infection is relatively high. Osteoset-T® (Wright Medical) is a medical grade calcium sulfate bone graft substitute which is enhanced for use in infected sites by incorporating 4% tobramycin sulfate. The tobramycin is released locally, allowing therapeutic antibiotic levels at the graft site, while maintaining low systemic antibiotic levels. This local treatment of infection allows new bone formation in the defect site, while decreasing potential systemic effects. Purpose/aim. Prevention and treatment of postoperative osteomyelitis by introducing alcoholic hand-sanitizers and the use of wound debridement and implantation of a medicated bone graft substitute. Materials and Methods. We treated some existing osteomyelitis cases and some open fractures with the medicated bone graft substitutes, at Kilembe Mines Hospital, Uganda. A proper debridement with sequestrectomy when needed was performed after which the pellets were implanted and the wound was closed. A preoperative X-ray was taken as well as clinical pictures. Post-operative x-rays were obtained at 6 weeks post-operative and 6 months post-operative when possible. The case presented in this abstract is a 25year old nurse with a bilateral open tibia fracture due to a motorcycle accident. A proper debridement and plate and screw osteosynthesis was performed after which the pellets were implanted underneath the plate. After surgery systemic antibiotics were given and the wound-dressings were changed when dirty. Results. The case presented is currently 6 months post-operatively and is able to walk without support. The fracture is fully consolidated and the wounds are healed without any sign of infection. Conclusion. Even though the clinical follow-up is not easy in this developing country setting, we were able to evaluate some patients postoperatively. By introducing better hand hygiene (by use of alcoholic hand sanitizers) and medicated bone graft substitutes, we hope to be able to prevent osteomyelitis after open fractures and also to treat chronic osteomyelitis cases. More people are being treated at the moment and a case-control study will be started soon

Purpose. The purpose was to compare the accuracy of the method using 3D printing model with the method using picture archiving and communication system (PACS) images in high tibial osteotomy (HTO). Materials and methods. This study analyzed 40 patients with varus deformity and medial osteoarthritis. From 2012 to 2016, patients underwent HTO using either 3D printing model (20 knees) or method based on a PACS image (20 knees). After obtaining the correction angle for the target point (62.5% point of the mediolateral tibial plateau width), in the 3D printing method, the wedge-shaped 3D-printed model was designed with the measured angle and osteotomy section and was produced by the 3D printer. The PACS method used preoperative radiographs to shift the weight bearing axis. The accuracy of the HTO and the proportion of acceptable range (62.5 ± 5%) at each method was compared using the full-length lower limb radiographs at the sixth postoperative week. The pre and postoperative posterior tibial slope angle was also compared at each method. Results. The weight bearing line on the tibial plateau was corrected from a preoperative 21.1 ± 11.8% to a postoperative 61.6 ± 3.4% in the 3D group and from 19.5 ± 12.3% to 61.4 ± 8.0% in the PACS group. The patients in an acceptable range were more in 3D printing group (80%) than in PACS group (60%) (p=0.028). The mean of absolute difference with the target point was less in 3D printing groups (2.4 ± 2.5) than PACS group (6.2 ± 5.1) (p=0.006). The posterior tibial slope was not significantly different in 3D printing group (8.6° to 8.9°, p=0.073), whereas different in PACS group (9.9° to 10.5°, p=0.042). Conclusions. In HTO, correction based on the 3D printing method was more accurate than correction using the PACS method

Aim. One of the most challenging problems in total knee arthroplasty (TKA) is periprosthetic infection. A major problem that arises in septic revision TKA (RTKA) are extended bone defects. In case of extended bone defects revision prostheses with metaphyseal sleeves are used. Only a few studies have been published on the use of metaphyseal sleeves in RTKA - none were septic exclusive. The aim of our study was to determine the implant survival, achieved osseointegration as well as the radiological mid-term outcomes of metaphyseal sleeve fixation in septic two-stage knee revision surgery. Method. Clinical and radiological follow-up examinations were performed in 49 patients (25 male and 24 female). All patients were treated with a two-stage procedure, using a temporary non-articulating bone cement spacer. The spacer was explanted after a median of 12 weeks (SD 5, min. 1 – max. 31) and reimplantation was performed, using metaphyseal sleeves in combination with stem fixation. Bone defects were classified on preoperative radiographs using the Anderson Orthopaedic Research Institute (AORI) classification. During follow-up postoperative range of motion (ROM) was measured and radiographs were performed to analyse: (i) osseointegration (radiolucent lines and spot welds), (ii) leg alignment, (iii) patella tilt and shift. Results. All types of bone defects were found on the tibial (4× type 1, 7× type 2a, 26× type 2b, 9× type 3) as well as on the femoral side (1× type 1, 4× type 2a, 20× type 2b, 6× type 3). Mean follow-up time was 4.7 years (minimum 1 year). In total 12 knees (24.5%) had to be re-revised, all due to re-infection. We did not encounter any case of aseptic loosening. In 3 patients (6.8%) we detected an insufficient osseointegration, but no patient had to be re-revised due to only minimal or to the absence of symptoms and no clinical signs of loosening. The ROM (mean 93°, SD 20.6, min. 25° max. 125°) has shown very satisfying results at the time of follow-up. Malalignment was detected in 4 patients (10.3%), a patella tilt in 7 (19.4%) and a patella shift in 14 (48.3%). Conclusions. Metaphyseal Sleeves have shown very promising mid-term results regarding osseointegration and aseptic implant survival in RTKA with compromised metaphyseal bone stock. Our results indicate that they are a reliable fixation option in septic RTKA patients

Purpose. Evaluation of status of collateral ligament & prediction of post-op alignment is important for partial knee replacement because during UKA the ligament can't be released & overcorrection or severe varus alignment result in poor clinical result. Evaluation of ligament could be done with valgus stress or distraction. The authors compare the stress view & distractive CT scanogram. to know the effectiveness regarding the prediction of final alignment. Material & Method. 19 knee from the 16 people receiving partial knee replacement was studied, we measure the anatomical axis &mechanical axis of the valgus stress view & distractive CT scanogram & post-operative whole leg radiogram. Result. anatomic axis in preoperative radiograph of a 30-degree valgus load was 7.31 ± 3.33, that of full-length radiograph of postoperative period was 3.11 ± 2.12, there was a significant difference between both groups (p = 0). Anatomic axis in preoperative CT anatomical valgus axis was 2.36 ± 2.04 & that of full-length radiograph of postoperative period was 3.11 ± 2.12, there were not significantly different. (P = 0.209). mechanical axis in preoperative of distraction CT scanogram were 4.15 ± 2.23 & that of post-op full length radiogram was 3.43 ± 2.42,& there were no significant difference between both groups. (P = 0.314) displacement of the mechanical axis of the surgery was 29.27 ± 14.08% in CT,& that of post-op full length radiogram was 34.45 ± 11.9%, there was no significant difference in both groups. (P = 0.261). Conclusion. InPartial knee replacement, distractive CT scanogram effectively predict the post-operative alignment, & valgus stress view show the overcorrected alignment

Objectives. Delayed gadolinium enhanced MRI of cartilage (dGEMRIC) is a novel MRI-based technique with intravenous contrast agent that allows an objective quantification of biochemical cartilage properties. It enables a ‘monitoring' of the loss of cartilage glycosaminoglycan content which ultimately leads to osteoarthritis. Data regarding the longitudinal change of cartilage property after joint preserving hip surgery is sparse. We asked (1) if and how the dGEMRIC-index changes in patients undergoing open/arthroscopic treatment of femoroacetabular impingement (FAI) one year postoperatively compared to a control group of patients with non-operative treatment; (2) and if a change correlates with the clinical short term outcome. Methods. IRB-approved prospective comparative longitudinal study of two groups involving a total of 61 hips in 55 symptomatic patients with FAI. The ‘operative' group consisted of patients that underwent open/arthroscopic treatment of their pathomorphology. The ‘non-operative' group consisted of conservatively treated patients. Groups were comparable for preoperative radiographic arthritis (Tönnis score), preoperative HOOS- and WOMAC-scores and baseline dGEMRIC indices. All patients eligible for evaluation had preoperative radiographs and dGEMRIC scans at baseline and repeated dGEMRIC scans using the same scanner and protocol. (1) dGEMRIC indices of femoral and acetabular cartilage were assessed separately on the initial and follow-up dGEMRIC scans. Radial images were reformatted from a 3D T1 map for measurements. Regions of interest were placed manually peripherally and centrally within the cartilage based on anatomical landmarks at the 12 ‘hour' position of the clcok-face with the help of radial high-resolution PD-weighted MR images. (2) Patient-reported outcome was evaluated at baseline and at 1 year follow-up: Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Hip disability and Osteoarthritis Outcome Score (HOOS). Statistical analysis included Student's t-Tests, Mann-Whitney U-tests and Wilcoxon signed-rank tests (p<0.05). Results. On the acetabular side, the dGEMRIC index decreased significantly (p<0.05) in 17/20 (85%) zones respectively in 21/24 (88%) of femoral zones in the operated group [Fig. 1]. In the non-operative group, no acetabular zone and 2/24 (8%) femoral zones presented with a significant drop [Fig. 2]. After one year the WOMAC and the HOOS scores significantly improved (58±42 to 33±42; p= 0.007 respectively 63±16 to 74±18; p= 0.028) for the operative group, while there was no change (55±45 to 48±50; p= 0.825 respectively 63±14 to 66±19; p= 0.816) for the non-operative group. Discussion. Interestingly joint-preserving surgery for FAI led to a decline in biochemical cartilage properties on MRI at a one year follow-up despite the significant improvement of patient outcome. This short-term phenomenon was described after periacetabular osteotomy for correction of hip dysplasia in literature with a normalization of the dGEMRIC values at 2 years

Introduction. Cementless grit-blasted tapered-wedge titanium femoral stems are being used with increasing frequency in hip arthroplasty because of excellent long-term outcomes. However, periprosthetic femur fracture is a potentially worrisome phenomenon in these types of femoral stems. The aim of this study is to report the incidence of stem loosening in association with periprosthetic femur fractures following hip arthroplasty using cementless grit-blasted tapered-wedge stems. Materials & Methods. A total of 36 Vancouver Type B1 and B2 periprosthetic femur fractures following either hemiarthroplasty or total hip arthroplasty using cementless grit-blasted tapered-wedge titanium femoral stems (GB group) were identified from a retrospective review of the medical records at three participating academic institutions. The control group consisted of 21 Vancouver Type B1 and B2 periprosthetic femur fractures following either hemiarthroplasty or total hip arthroplasty using cementless proximal porous-coated femoral stems (PC group) at the same institutions during the same period of the study. All femoral stems included in this study had been a well-fixed state before the occurrence of periprosthetic femur fractures. All patients in both groups were treated surgically with either open reduction and internal fixation or femoral stem revision. Femoral stem stability was assessed by preoperative radiographs and was confirmed by intraoperative scrutinization. The incidence of stem loosening was compared between the groups. Results. There was no significant difference between the groups with respect to demographic data including age, gender, body mass index, primary diagnosis, Dorr types of proximal femur, and time to fracture. All fractures occurred from low-energy mechanisms. Mean age at the time of hip arthroplasty was 54.5 years in the GB group and 57.0 years in the PC group. Mean time interval between hip arthroplasty and periprosthetic fracture was 49.6 months in the GB group and 44.4 months in the PC group. At the time of the last follow-up, 29 (80.6%) of 36 fractures was Vancouver B2 in the GB group, whereas only 3 (14.3%) of 21 fractures was Vancouver B2 in the PC group (P <0.001). Conclusions. High incidence of stem loosening was developed in association with periprosthetic femur fractures in previously well-fixed cementless grit-blasted tapered-wedge femoral stems in our population. We believe that this is an underreported phenomenon of these types of stem design

Background. Total elbow arthroplasty (TEA) has become an established procedure in the treatment of patients with rheumatoid arthritis (RA). However, there is little information on whether limited extension of the elbow affects clinical outcome scores after TEA and what causes the limited extension. Methods. We retrospectively analyzed fifty-four cases of primary TEA in patients with RA. There were seven men and thirty-nine women with a mean age of 63.6 years (range, thirty to eighty years). Thirty-seven of Coonrad-Morrey and seventeen of Discovery prostheses were used. The mean length of follow-up was 7.1 ± 4.0 years (range 2.0–14.6 years). Mayo Elbow Performing Score (MEPS) and radiological measurements were recorded. Anteroposterior and lateral radiographs were assessed before and after the operation and at the latest follow-up. Widening of the joint space was calculated by subtracting the length measured on the postoperative radiograph from that on the preoperative radiograph. Results. MEPS was significantly improved after surgery (51.2 to 91.1), especially in the domains of pain (18.6 to 43.1), stability (5.9 to 10) and daily function (10.7 to 21.0). Range of motion was significantly improved, in flexion (111.3° to 140.6°), pronation (62.1° to 72.3°), and supination (60.2° to 72.3°), but not in extension (30.0° to 28.8°). Simple and multivariate analyses showed that longer disease duration (p = 0.004), higher Larsen grade (p = 0.013), worse pronation/supination arc (p = 0.004) and worse postoperative extension (p = 0.033), but not postoperative flexion (p = 0.532), were significantly correlated with lower MEPS daily function. Conversely, simple and multivariate analyses showed that worse postoperative extension was correlated with lower MEPS daily function (p = 0.005) and worse preoperative extension (p < 0.001). Radiological analyses showed that, in the limited extension group (≧40°), the degree of extension was correlated with radiological widening of the joint. Conclusions. In linked TEA, perioperative widening of the elbow joint caused limited extension and worse daily function in patients with RA

Purpose. Use of theguide angle method using intramedullary guide angle for distal femoral cutting in total knee arthroplasty may cause error when rotation of the femur occurs or the insertion point of the intramedullary guide is incorrectly positioned in preoperative radiography. On the other hand, use of the measured cutting method, in which resection of distal femoral condyles is performed according to predicted measured thickness in a preoperative radiograph can allow for correction of these errors intraoperatively. Therefore, we compared these two distal femoral bone cutting methods for restoration of accurate coronal alignment. Methods. Between 2010 and 2012, 47 patients (70 knees) underwent total knee arthroplasty for treatment of osteoarthritis with varus deformity and flexion contracture less than 10 degrees. Bone resection depending on distal femur resection thickness measured before the operation was performed in 38 cases (Group I). Distal femoral cutting using the guide angle was performed in 32 cases (Group II). Radiographic evaluation, including mean value of lower leg mechanical axis angle and the frequency of errors of more than 3 degrees, was performed for comparison between the two groups. Results. In Group I, mechanical axis was corrected from 8.4 ± 4.9 degrees (−7.2 to 16.9) on average before the operation to 0.1 ± 2.4 degrees (−5.87 to 2.98) after the operation, and, in Group II, from 6.7 ± 3.6 degrees (0.4 to 14.7) on average before the operation to 0.5 ± 2.8 degrees (−5.4 to 6.9) after the operation. No statistically significant difference in mechanical axis (p = 0.554) was observed between the two groups after the operation, and no difference in errors of more than 3 degrees was observed between the two groups, with four of 38 cases (11 %) in Group I and six of 32 cases (19%) in Group II (p = 0.495). Conclusions. No significantly different results were observed between the measured resection technique and the existing guide angle technique. Therefore, predictive measurement of distal femoral cutting thickness is another useful method for restoration of accurate coronal alignment

Open reduction and internal fixation of acetabular fractures demands detailed preoperative planning, and given their frequent complexity, a thorough understanding of their three-dimensional (3D) form is necessary. This study aims to assess if the use of dynamic 3D models will improve preoperative planning of acetabular fractures. In this study, three experienced pelvic trauma surgeons were provided with computer based dynamic 3D models in addition to preoperative radiographs, CT scans and static 3D reconstructions of 17 acetabular fractures operatively managed at the Royal Melbourne Hospital. Surgeons, blinded to any previous operative plan or patient detail, then classified fracture type and made preoperative surgical plans. Comparison was then made to classification and operative approach documented in the patient's operation notes. Comparison was then made with regard to surgical plan and planning time with or without access to dynamic 3D models. In complex cases the additional information provided by dynamic 3D modelling was found to reduce planning time and, in some cases, change the surgical plan. For complex acetabular fractures we recommend that surgeons should have access to computer-based dynamic 3D models of the injuries for pre-operative planning

Background. Nutrient arteries appear as radiolucent lines (Fig. 1) on account of their topography and may erroneously suggest fracture lines. Question/purpose. (1) How frequently the nutrient artery canals of the femur are seen after cementless THA and their distribution patterns are; (2) How to distinguish visible nutrient artery canal from fracture lines; and (3) Whether clinical significance of the nutrient artery canals of the femur in patients with primary cementless THA is evident or not. Methods. Between March 2010 and December 2013, 93 patients 102 hips were enrolled for this retrospective analysis. The number, location, direction of obliquity, length of the nutrient artery canals of the femur, the distance between the tip of the greater trochanter and the proximal end of the nutrient artery canal were measured. Results. The nutrient artery canal of the femur in the cortex on preoperative cross-table lateral hip radiograph (NACL) was seen in 32 of 102 hips (31.4%), the nutrient artery canal of the femur in the medullary cavity on preoperative anteroposterior hip radiograph (NAMA) was seen in 17 hips (16.6%), and the nutrient artery canal of the femur in the medullary cavity on preoperative cross-table lateral hip radiograph (NAML) was seen in 5 hips (4.9%). The nutrient artery canal of the femur in the cortex on anteroposterior hip radiograph was not seen at all. Entire visible NACLs coursed upward obliquely from postero-distal to antero-proximal direction. An average length of NACL was 32.6 ± 13.9 mm and an average distance between the tip of the greater trochanter and the proximal end of the NACL, NAMA and NAML was 130.1 ± 15.8 mm, 105.1 ± 13.4 mm and 102.5 ± 7.4 mm, respectively. NACL was seen postoperatively in 37 of 102 hips (36.3%), in 24 of which (23.5% overall) both ends of the nutrient artery canal were distal to the implant tip and in 13 of which (12.8% overall) one of the ends of the nutrient canal was at least proximal to the implant tip. NAMA was seen postoperatively in 8 of 102 hips (7.8%) and NAML was seen postoperatively in 6 hips (5.9%), in 5 of which (4.9% overall) femoral stems fully masked the nutrient artery canal and in 9 of which (8.8% overall) a nutrient artery canal was visible postoperatively, but its proximal end was not defined because of implant shadowing. The length of stems which fully masked the nutrient artery canals postoperatively were at least 150 mm or larger. Six (5.9%) intraoperative periprosthethic femoral fractures were detected (Fig. 2 and 3). One was type TL, one was type A1, three were type B2 and one was type B3. Type B2 fractures showed new or additional radiolucent lines on intraoperative and/or postoperative radiographs by comparison with the preoperative radiographs. Conclusions. The knowledge of radiographic features of the nutrient artery canals of the femur may be useful to distinguish them from intraoperative fractures after cementless THA

Templates are used in the preoperative planning of many orthopaedic procedures. The magnification of the bones on preoperative radiographs can vary despite using standardised radiological techniques. Templates will give misleading measurements unless this magnification is quantified. A coin may be used to calculate the magnification, with significant improvement in the accuracy of templating (p = 0.05). A group of patients undergoing uncemented arthroplasty of the hip was at high risk for intraoperative fracture of the femur because the magnification of the radiograph was larger than that of the template

Permanent patellar subluxation is treated with surgeries such as proximal realignment and distal realignment, however, it is difficult to cure this condition by using any methods. We performed mobile-bearing total knee arthroplasty (TKA) in a case of severe knee osteoarthritis complicated with permanent patellar subluxation since childhood, and obtained good results without performing any additional procedures. The patient was an 82-year-old woman with severe pain in the left knee. During the initial examination, the range of motion of the left knee joint was -10°of extension to 140°of flexion, and the Japanese Orthopaedic Association (JOA) score for knee osteoarthritis was 40 points (maximum score: 100). Preoperative radiographs showed a varus deformity in the left lower extremity with a femorotibial angle (FTA) of 188°, the axial view showed luxation of the patella. We performed TKA using a mobile-bearing implant. Intraoperative findings revealed that the central articular surface of the distal femur had disappeared, and that the patellar articular surface was concave and dome-shaped. The lateral patellofemoral ligament was released; this procedure was identical to that performed in conventional TKA. Postoperative radiographs showed good alignment, with an FTA of 173°. In the axial view, the patella was located in a reduced position at any angle of knee joint flexion. The postoperative range of motion of the left knee joint was 0°of extension to 130°of flexion. The patient was able to walk without the support of a T-shaped cane. There are many surgical treatments for permanent patellar subluxation. The appropriate treatment is selected according to the type and seriousness of the dislocation and the age of the patient. From the findings of the present case, we believe that in a case of knee osteoarthritis complicated with permanent patellar subluxation, surgery performed using a mobile-bearing implant would eliminate the necessity of performing additional proximal realignment and distal realignment

Introduction. Total knee arthroplasty is effective for the management of osteoarthritis of the knee. Conventional techniques utilizing manual instrumentation (MI) make use of intramedullary femoral guides and either extramedullary or intramedullary tibial guides. While MI techniques can achieve excellent results in the majority of patients, those with ipsilateral hardware, post-traumatic deformity or abnormal anatomy may be technically more challenging, resulting in poorer outcomes. Computer-assisted navigation (CAN) is an alternative that utilizes fixed trackers and anatomic registration points, foregoing the need for intramedullary guides. This technique has been shown to yield excellent results including superior alignment outcomes compared to MI with fewer outliers. However, studies report a high learning curve, increased expenses and increased operative times. As a result, few surgeons are trained and comfortable utilizing CAN. Patient-specific instrumentation is an alternative innovation for total knee arthroplasty. Custom guide blocks are fabricated based on a patient's unique anatomy, allowing for the benefits of CAN but without the increased operative times or the high learning curve. In this study we sought to evaluate the accuracy of PSI techniques in patients with previous ipsilateral hardware of the femur. Methods. After reviewing our database of 300 PSI total knee arthroplasty patients, 16 were identified (10 male, 6 female) using the Zimmer NexGen Patient Specific Instrumentation System. Fourteen patients included in the study had a preexisting total hip arthroplasty on the ipsilateral side [Figure 1], 1 had a sliding hip screw, and 1 patient had a cephalomedullary nail. Postoperative mechanical axis alignment measurements were performed using plain long-standing radiographs [Figure 2]. The American Knee Society Score was used to evaluate clinical outcomes postoperatively. Results. Sixteen total knee arthroplasties were performed using PSI, all in the setting of previous ipsilateral hardware placement. The average age at the time of surgery was 72, with patients ranging from 56 to 85 years of age [Table 1]. 11 of the included knees had a preoperative varus alignment and 5 had valgus alignment. The average value of a deformity identified via the preoperative planning software was 7.9°(1.5°–15.7°). The average value of a deformity identified via preoperative radiographs was 10.1°(2.2°–14.7°). Average postoperative mechanical axis was 3.1° (1°–5.3°) measured from plain radiographs. Average angle between the FMA and femoral component was 90.0° (85.3°–94.1°). The average angle between the TMA and tibial component was 90.6°(87.6°–92.9°). The average difference between the femoral mechanical and anatomic axes was 5.9°(3.4°–7.0°). The average discrepancy between medial and lateral joint space on an anterior-posterior standing radiograph was 0.4mm(0.0mm–1.1mm). At an average of 4.5 months follow-up, American Knee Society knee scores show an aggregate average score of 82.94. Conclusions. Patient specific instrumentation (PSI) is an innovative technology in TKA that replaces the use of intramedullary femoral guides and either extramedullary or intramedullary tibial guides. This study demonstrates that PSI is capable of producing favorable radiographic and clinical outcomes despite preexisting ipsilateral hardware, which may otherwise preclude the use of customary manual instrumentation. We believe PSI is an accurate and effective tool for use in patients with preexisting ipsilateral hardware