Post-operative check radiographs following Total Hip Replacements (THR) are routine practice in most orthopaedic units. In our unit an Anteroposterior and Turned Lateral View (TLV) radiograph was used routinely in this assessment, but the TLV method has anecdotally been reported as painful by patients. We undertook a study to evaluate patients' experiences of pain using this technique and to consider if a change to a Horizontal Beam Lateral View (HBLV) radiograph method would result in a reduction in pain. The study was conducted in two phases. Patients who underwent a primary THR and subsequent post-operative TLV over 3months (n=46) were contacted by telephone and asked to grade their experience using a numerical and descriptive pain scale. After a change in practice to HBLV, the study was repeated (n=53) to identify any difference in pain. Ten radiographs were randomly selected from each group and assessed for radiation exposure and quality by two independent assessors. 87.0% of patients who underwent the TLV radiograph described the post-operative radiograph as painful, with a mean pain score of 7.44+1.5. After a change in practice to the HBLV radiograph, only 28.4% of patients experienced any pain, with a significantly lower mean pain score of 1.00+1.89 (p< 0.001). There was a significant increase in radiation dose in the HBLV vs. TLV method (62.4mAs vs. 25.8mAs, p< 0.001). HBLV X-ray quality was only slightly inferior to TLV when evaluating stem alignment and cement mantle quality. There was a dramatic reduction in both number of patients experiencing pain and level of pain experienced when switching from TLV to HBLV radiographs; this is most likely due to reduced direct pressure on the wound post-operatively. X-ray quality was not compromised, and whilst there was increased radiation exposure, the benefits in patient experience were felt to outweigh this. We recommend the HBLV radiograph method when performing a lateral post-operative check x-ray following THR

Introduction: The radiographic evaluation of the antero-lateral femoral head is an essential tool for the assessment of cam type of femoroacetabular impingement. Computerised tomography (CT), magnetic resonance imaging and frog lateral plain radiograph views have all been suggested as imaging options for this type of lesion. The alpha angle is accepted as a reliable indicator of cam type of impingement and this may also be used as an assessment tool for successful operative correction of the cam lesion. The aim of our study was to analyse the reliability of The frog lateral view plain radiographs to analyse the alpha angle in cam femoroacetabular impingement. Patients and Methods: Thirty two patients who presented with femoroacetabular impingement were studied. Interobserver reliability for assessment of alpha angles on frog lateral radiographic view was analysed using intraclass correlation coefficient. The alpha angles measured on frog lateral views using digital templating tools were compared to those measured on CT scans. Results: A high interobserver reliability was noted for the assessment of alpha angles on frog lateral views with a correlation coefficient of 0.83. The average alpha angles measured on frog lateral views was 58.71 degrees (range 32 to 83.3). The average alpha angle measured on CT was 65.11 degrees (range 30 to 102). However, a poor correlation (Spearman r of 0.2) was noted between the measurements using the two systems. Conclusions: Frog lateral plain radiographs are not reliable predictors of alpha angle. Various factors may be responsible for this such as the projection of the radiographs, patient positioning and quality of images. CT imaging may be necessary for accurate measurement of the alpha angle

Radiographic evaluation of the anterolateral femoral head is an essential tool for the assessment of cam type of femoroacetabular impingement. Computerised tomography (CT), magnetic resonance imaging and frog lateral plain radiograph views have all been suggested as imaging options for this type of lesion. Alpha angle is accepted as a reliable indicator of cam type of impingement and this may also be used as an assessment tool for successful operative correction of the cam lesion. The aim of our study was to analyse the reliability of frog lateral view plain radiographs to analyse the alpha angle in cam femoroacetabular impingement. Thirty two patients who presented with femoroac-etabular impingement were studied. Interobserver reliability for assessment of alpha angles on frog lateral radiographic view was analysed using intraclass correlation coefficient. The alpha angles measured on frog lateral views using digital templating tools were compared to those measured on CT scans. A high interobserver reliability was noted for the assessment of alpha angles on frog lateral views with a correlation coefficient of 0.83. The average alpha angles measured on frog lateral views was 58.71 degrees (range 32 to 83.3). The average alpha angle measured on CT was 65.11 degrees (range 30 to 102). However, a poor correlation (Spearman r of 0.2) was noted between the measurements using the two systems. Frog lateral plain radiographs are not reliable predictors of alpha angle. Various factors may be responsible for this such as the projection of the radiographs, patient positioning and quality of images. CT imaging may be necessary for accurate prediction of alpha angle

Purpose of the study: It has been demonstrated that navigation systems improve the quality of implantation of total knee arthroplasty (TKA). The definitions of the reference alignment for the femur are not however consensual. We wanted to define the different alignments of the femur on the lateral view, including the femoral head and comparing the alignments with those defined by the measured axes during navigated implantation. Material and methods: We analysed 30 navigated TKA or unicompartmental prosthesis implantations. The following lines were drawn on the pre and postoperative lateral telemetric views: anatomic axis aligned on the anterior cortical of the femur, mechanical alignment n°1 (centre of the femoral head to the most distal point of the Blumensaat line), mechanical alignment n°2 (centre of the femoral head to the junction between the anterior two-thirds and the posterior third of the femoral condyles). The anatomic diaphyseal alignment was taken as the reference and the angles between this reference line and the other lines was measure. In addition, the sagittal orientation of the femoral component measured during the operation by the navigation system in relation to the n°2 mechanical alignment was noted; this orientation was also measured on the postoperative lateral telemetric views in relation to this same mechanical alignment. Results: The mean difference between the anatomic cortical alignment and the reference was 0.3 (−1 to +). The mean difference between the n°1 mechanical alignment and the reference was −1.1 (−5 to +3). The mean difference between the mechanical alignment n°2 and the reference was 0.8 (−4 to 4). The mean intraoperative sagittal orientation of the femoral component was 0.0 (−2 to 2). The mean postoperative sagittal orientation of the femoral component was 1.1 (−4 to 6). Discussion: The differences between the orientations of the different sagittal alignments of the femur were minimal. The cortical axis has a smaller variance and could be considered as the most reliable reference, but this alignment does not include the femoral anteversion. The difference between the sagittal orientation of the femoral component as measured by the navigation system and as measured on the postoperative x-rays was also minimal, and probably of no significance clinically. Conclusion: The choice of the sagittal alignment of the femur is of little importance. The intraoperative navigated measurement of the sagittal orientation of the femoral component is reliable

Introduction. Deciding the acetabular cup inclination and anteversion is an important step in total hip arthroplasty. Despite numerous studies focusing on enhancement of precise positioning into anatomical safe zone, problem remains regarding which is the “optimal anteversion” and what is the proper anatomical reference during the surgery. Objectives. The purpose of this study is to evaluate pelvic tilt angle measured in standing lateral view of pelvis in patients with hip osteoarthritis, and to find out the correlations between pelvic tilt angle (on Lewinnek anterior pelvic plane) and optimal anteversion position in total hip arthroplasty surgery. Results. The average pelvic tilt angle is 8.79 degree with standard deviation 8.25 degree. There have no statistically significant difference between the pelvic tilt angles of male and female patients, or patients received total hip arthroplasty and patients did not received surgery. The pelvic tilt angle significantly greater in patients older than 60 years old compared with patients younger than 60 years old (12 degree Vs 4 degree, p<0.005). Conclusions. There are large variations in the pelvic AP tilting between individuals, and the posterior tilting of pelvis increased with aging. Our findings suggested that instead of body axis measured when patient is in decubitus position on the table, cup positioning during total hip arthroplasty should be based on the functional position when patients is in upright position. The difference between functional position and bony axis might increase with age; hence increase the risk of over anteversion in cup positioning. This might lead to impingement between cup and femur prosthesis and cause early failure or dislocation. While positioning the patient using lateral position, surgeons should pay attention to anterior pelvic plane and pelvic tilt angle (taking from lateral standing position) for estimation of anteversion of cup

Cam type femoroacetabular impingement (FAI) is due to an aspheric femoral head, which is best quantified by the alpha angle described on MRI and CT-scan. Radiographic measurement of the alpha angle is not well codified and studies from the literature cannot conclude on the best view to measure it. Most authors also describe a mixed type FAI which associates an aspheric femoral head with an excessive anterior acetabular coverage of the femoral head. Anterior center edge (ACE) angle has been described on the false profile view to measure anterior acetabular coverage in hip dysplasia and has never been evaluated in FAI. In this study, we developed a new lateral hip view which associates a lateral view of the femoral neck and a false profile view of the acétabulum, which we called profile view in impingement position (PVIP). Twenty six patients operated for FAI had CT-scan, the PVIP and the false profile view of one or two hips according to pain. A control group of 19 patients who did not suffer from the hip had the PVIP. Alpha angles were measured twice on 17 CT scan of FAI patients by two observers and compared with the alpha angles measured on the corresponding hip PVIP by a correlation analysis. Alpha angles were measured twice on 45 PVIP in FAI patient and on 19 PVIP in the control group by three observers. ACE angles were measured once on 15 PVIP and on 15 false profile views. Means were compared by two tail paired t-tests, intra- and inter-observer reliability were measured by intraclass correlation coefficient. Mean alpha angle on CT scan was 65.8° and 65.6° for observers 1 and 2 respectively (p>0.05). It was 63.6° and 64.3° on the PVIP (p>0.05). No significant difference was found between CT scan and radiographic measurements, and Pearson's correlation coefficients were good at 0.74 and 0.8. ICC was 0.86 for inter-rater reliability, and 0.91 for intra-rater reliability for CT-scan alpha angle measures. ICC for PVIP measures varied from 0.82 to 0.9 for intra-rater reliability and from 0.6 to 0.9 for inter-rater reliability. Mean alpha angle measured on PVIP in FAI patients was 63.3° and was 44.9° in control subjects and the difference was significant (p<0.001) for the three observers. None of the FAI patients and 88% of the control subjects had an alpha angle < 50°. Mean ACE angle was 26.8° on PVIP and 32.8° on the false profile view, the difference was significant (p=0.015), and the Pearson's correlation coefficient was moderate (r=0.58). The PVIP is a reliable radiographic view to measure the alpha angle. It allows a good quantification of the alpha angle comparable to CT-scan measurements and permits to differentiate patients from control subjects. PVIP is not a good view to quantify anterior edge angle probably because of acetabular retroversion due to the hip flexion needed in this view. Mean ACE angle measured on the false profile view in FAI patient was comparable to ACE angle in general population reported in the literature

Aims. Proximal femur fractures treatment can involve anterograde nailing with a single or double cephalic screw. An undesirable failure for this fixation is screw cut-out. In a single-screw nail, a tip-apex distance (TAD) greater than 25 mm has been associated with an increased risk of cut-out. The aim of the study was to examine the role of TAD as a risk factor in a cephalic double-screw nail. Methods. A retrospective study was conducted on 112 patients treated for intertrochanteric femur fracture with a double proximal screw nail (Endovis BA2; EBA2) from January to September 2021. The analyzed variables were age, sex, BMI, comorbidities, fracture type, side, time of surgery, quality of reduction, pre-existing therapy with bisphosphonate for osteoporosis, screw placement in two different views, and TAD. The last follow-up was at 12 months. Logistic regression was used to study the potential factors of screw cut-out, and receiver operating characteristic curve to identify the threshold value. Results. A total of 98 of the 112 patients met the inclusion criteria. Overall, 65 patients were female (66.3%), the mean age was 83.23 years (SD 7.07), and the mean follow-up was 378 days (SD 36). Cut-out was observed in five patients (5.10%). The variables identified by univariate analysis with p < 0.05 were included in the multivariate logistic regression model were screw placement and TAD. The TAD was significant with an odds ratio (OR) 5.03 (p = 0.012) as the screw placement with an OR 4.35 (p = 0.043) in the anteroposterior view, and OR 10.61 (p = 0.037) in the lateral view. The TAD threshold value identified was 29.50 mm. Conclusion. Our study confirmed the risk factors for cut-out in the double-screw nail are comparable to those in the single screw. We found a TAD value of 29.50 mm to be associated with a risk of cut-out in double-screw nails, when good fracture reduction is granted. This value is higher than the one reported with single-screw nails. Therefore, we suggest the role of TAD should be reconsidered in well-reduced fractures treated with double-screw intramedullary nail. Cite this article: Bone Jt Open 2024;5(6):457–463

Spinopelvic mobility describes the change in lumbar lordosis and pelvic tilt from standing to sitting position. For 1° of posterior pelvic tilt, functional cup anteversion increases by 0.75° after total hip arthroplasty (THA). Thus, spinopelvic mobility is of high clinical relevance regarding the risk of implant impingement and dislocation. Our study aimed to 1) determine the proportion of OA-patients with stiff, normal or hypermobile spino-pelvic mobility and 2) to identify clinical or static standing radiographic parameters predicting spinopelvic mobility. This prospective diagnostic cohort study followed 122 consecutive patients with end-stage osteoarthritis awaiting THA. Preoperatively, the Oxford Hip Score, Oswestry Disability Index and Schober's test were assessed in a standardized clinical examination. Lateral view radiographs were taken of the lumbar spine, pelvis and proximal femur using EOS© in standing position and with femurs parallel to the floor in order to achieve a 90°-seated position. Radiographic measurements were performed for the lumbar lordosis angle (LL), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI) and pelvic-femoral-angle (PFA). The difference in PT between standing and seated allowed for patient classification based on spino-pelvic mobility into stiff (±30°). From the standing to the sitting position, the pelvis tilted backwards by a mean of 19.6° (SD 11.6) and the hip was flexed by a mean of 57° (SD 17). Change in pelvic tilt correlated inversely with change in hip flexion. Spinopelvic mobility is highly variable in patients awaiting THA and we could not identify any clinical or static standing radiographic parameter predicting the change in pelvic tilt from standing to sitting position. In order to identify patients with stiff or hypermobile spinopelvic mobility, we recommend performing lateral view radiographs of the lumbar spine, pelvis and proximal femur in all patients awaiting THA. Thereafter, implants and combined cup inclination/anteversion can be individually chosen to minimize the risk of dislocation. No predictors could be identified. We recommend performing sitting and standing lateral view radiographs of the lumbar spine and pelvis to determine spinopelvic mobility in patients awaiting THA

Aims. In UK there are around 76,000 hip fractures occur each year 10% to 15% of which are undisplaced intracapsular. There is considerable debate whether internal fixation is the most appropriate treatment for undisplaced fractures in older patients. This study describes cannulated hip screws survivorship analysis for patients aged ≥ 60 years with undisplaced intra-capsular fractures. Methods. This was a retrospective cohort study of consecutive patients aged ≥ 60 years who had cannulated screws fixation for Garden I and II fractures in a teaching hospital between March 2013 and March 2016. The primary outcome was further same-side hip surgery. Descriptive statistics were used and Kaplan-Meier estimates calculated for implant survival. Results. A total of 114 operations were performed on 112 patients with a mean age of 80.2 years (SD 8.9). The 30-day and one-year mortality were 1% (n = 1) and 13% (n = 15), respectively. Median follow-up was 6.6 years (interquartile range 6.0 to 7.3). Kaplan-Meier estimates showed a survivorship of 95% at one year and 90% at five years (95% confidence interval 84% to 95%) for cannulated screws. Nine patients underwent further hip surgery: four revision to total hip arthroplasty, one revision to hemiarthroplasty, three removals of screws, and one haematoma washout. Posterior tilt was assessable in 106 patients; subsequent surgery was required in two of the six patients identified with a posterior angle > 20° (p = 0.035 vs angle < 20°). Of the 100 patients with angle < 20°, five-year survivorship was 91%, with seven patients requiring further surgery. Conclusion. This study of cannulated hip screw fixation for undisplaced fractures in patients aged ≥ 60 years reveals a construct survivorship without further operation of 90% at five years. Cannulated screws can be considered a safe reliable treatment option for Garden I and II fractures. Caution should be taken if posterior tilt angle on lateral view exceeds 20°, due to a higher failure rate and reoperation, and considered for similar management to Garden III and IV injuries. Cite this article: Bone Jt Open 2022;3(3):182–188

Lag screw cut-out is a serious complication of dynamic hip screw fixation in trochanteric hip fractures. Lag screw position is recognised as a crucial factor influencing the occurrence of lag screw cut-out. We propose a modification of the Tip Apex Distance (TAD) and hypothesize that it could enhance the reliability of predicting lag screw cut-out in these injuries. A retrospective study of hip fracture cases was conducted from January 2018 to July 2022. A total of 109 patients were eligible for the final analysis. The modified TAD was measured in millimetres, based on the sum of the traditional TAD in the lateral view and the net value of two distances in the anteroposterior (AP) view. The first distance is from the lag screw tip to the opposite point on the femoral head along the lag screw axis, while the second distance is from that point to the femoral head apex. The first distance is a positive value, whereas the second distance is positive if the lag screw is superior and negative if it is inferior. Receiver operating characteristic (ROC) curve analysis was used to assess the reliability of various parameters for evaluating the lag screw position within the femoral head. Factors such as reduction quality, fracture pattern according to the AO/OTA classification, TAD, Calcar-Referenced TAD, Axis Blade Angle, Parker’s ratio in the AP view, Cleveland Zone 1, and modified TAD were statistically associated with lag screw cut-out. Among the tested parameters, the novel parameter exhibited 90.1% sensitivity and 90.9% specificity for predicting lag screw cut-out at a cut-off value of 25 mm, with a p-value < 0.001. The modified TAD demonstrated the highest reliability in predicting lag screw cut-out. A value of 25 mm may potentially reduce the risk of lag screw cut-out in trochanteric hip fractures

Introduction. The Oxford Unicompartmental Knee Replacement (OUKA) is the most popular unicompartmental knee replacement (UKR) in the New Zealand Joint Registry with the majority utilising cementless fixation. We report the 10-year radiological outcomes. Methods. This is a prospective observational study. All patients undergoing a cementless OUKA between May 2005 and April 2011 were enrolled. There were no exclusions due to age, gender, body mass index or reduced bone density. All knees underwent fluoroscopic screening achieving true anteroposterior (AP) and lateral images for radiographic assessment. AP assessment for the presence of radiolucent lines and coronal alignment of the tibial and femoral components used Inteliviewer radiographic software. The lateral view was assessed for lucencies as well as sagittal alignment. Results. 687 OUKAs were performed in 641 patients. Mean age at surgery was 66 years (39–90yrs), 382 in males and 194 right sided. 413 radiographs were available for analysis; 92 patients had died, 30 UKRs had been revised and 19 radiographs were too rotated to be analysed the remainder were lost to follow-up. Mean radiograph to surgery interval was 10.2 years (7.1–16.2yrs). RLLs were identified in zone 1 (3 knees), zone 2 (2 knees), zone 3 (3 knees), zone 5 (3 knees), zone 6 (2 knees) and zone 7 (42 knees). No RLL had progressed, and no case had any osteolysis or prosthesis subsidence. Alignment in the coronal plane: mean 2.90° varus (9.30° varus - 4.49° valgus) of the tibial component to the tibial anatomic axis and the femoral component in mean 4.57° varus (17.02° varus - 9.3° valgus). Sagittal plane posterior tibial slope was a mean 6.30° (0.44° -13.60° degrees) and mean femoral component flexion of 8.11° (23.70° flexion – 16.43° extension). Conclusion. The cementless OUKA demonstrates stable fixation with low revision rates at our centre supporting results earlier published by the design centre

Abstract. Objective. Short-stem total hip arthroplasty (THA) aims to preserve the proximal bone stock for future revisions, so that the first revision should resemble a primary intervention rather than a revision. This study aimed to compare the clinical and radiological outcomes in revision THA after failed short stem versus after failed conventional stem THA. Methods. This study included forty-five patients with revision THA divided into three groups (15 each); group A: revision after short stem, group B: revision after conventional cementless stem and group C revision after conventional cemented stem. The studied groups were compared regarding 31 variables including demographic data, details of the primary and revision procedures, postoperative radiological subsidence, hospital stay, time for full weight bearing (FWB), preoperative and postoperative clinical scores. Results. Early stem subsidence (40%) was the main indication of revision in group A compared to peri-prosthetic femoral fractures (PFFs) (73.3%) and aseptic loosening (53.3%) in group B and C respectively (P=0.021). The mean time to revision was significantly shorter in group A (15 months) compared to 95.33 and 189.40 months in group B and C respectively. (P=0.005). Sixty % (9 patients) in group A were revised in the first year. The mean operative time, blood loss, postoperative blood transfusion and hospital stay were significantly lower in group A compared to group B and C (P<0.001, <0.001, 0.002 and 0.001 respectively). Revisions in group A were performed using either short stems (13.3%) or conventional stems (86.7%) whilst 80% of patients needed long stems and 20% of patients needed conventional stems in group B and C (P<0.001). The mean postoperative Harris Hip Score (HHS) at the latest follow up was 87.07, 87.53 and 85.47 in group A, B and C respectively. All PFFS had excellent results according to Beal's and Tower's criteria; all fractures healed and the implants were stable. Conclusion. The most common cause of failure of short stems is early stem subsidence. Short stem THA has specific indications and patient selection is very crucial. Preoperative templating for short stems and a detailed analysis of the individual patient anatomy in anteroposterior and lateral views are mandatory to predict the correct implant size more accurately. The use of intraoperative imaging can verify the sizing, implant position, and sufficient contact with the lateral cortex. Revision of short stem THA resembled the primary THA. If a standard implant can be used in a surgical revision instead of a longer revision stem, this can be considered as an advantage for the hip arthroplasty treatment concept. However, this only applies if the longevity of the first treatment with a short stem is comparable with that of a standard stem. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Primary care physicians rely on radiology reports to confirm a scoliosis diagnosis and inform the need for spine specialist referral. In turn, spine specialists use these reports for triage decisions and planning of care. To be a valid predictor of disease and management, radiographic evaluation should include frontal and lateral views of the spine and a complete view of the pelvis, leading to accurate Cobb angle measurements and Risser staging. The study objectives were to determine 1) the adequacy of index images to inform treatment decisions at initial consultation by generating a score and 2) the utility of index radiology reports for appropriate triage decisions, by comparing reports to corresponding images. We conducted a retrospective chart and radiographic review including all idiopathic scoliosis patients seen for initial consultation, aged three to 18 years, between January 1-April 30, 2021. A score was generated based on the adequacy of index images to provide accurate Cobb angle measurements and determine skeletal maturity (view of full spine, coronal=two, lateral=one, pelvis=one, ribcage=one). Index images were considered inadequate if repeat imaging was necessary. Comparisons were made between index radiology report, associated imaging, and new imaging if obtained at initial consultation. Major discrepancies were defined by inter-reader difference >15°, discordant Risser staging, or inaccuracies that led to inappropriate triage decisions. Location of index imaging, hospital versus community-based private clinic, was evaluated as a risk factor for inadequate or discrepant imaging. There were 94 patients reviewed with 79% (n=74) requiring repeat imaging at initial consultation, of which 74% (n=55) were due to insufficient quality and/or visualization of the sagittal profile, pelvis or ribcage. Of index images available for review at initial consult (n=80), 41.2% scored five out of five and 32.5% scored two or below. New imaging showed that 50.0% of those patients had not been triaged appropriately, compared to 18.2% of patients with a full score. Comparing index radiology reports to initial visit evaluation with <60 days between imaging (n=49), discrepancies in Cobb angle were found in 24.5% (95% CI 14.6, 38.1) of patients, with 18.4% (95% CI 10.0, 31.4) categorized as major discrepancies. Risser stage was reported in only 14% of index radiology reports. In 13.8% (n=13) of the total cohort, surgical or brace treatment was recommended when not predicted based on index radiology report. Repeat radiograph (p=0.001, OR=8.38) and discrepancies (p=0.02, OR=7.96) were increased when index imaging was obtained at community-based private clinic compared to at a hospital. Re-evaluation of available index imaging demonstrated that 24.6% (95% CI 15.2, 37.1) of Cobb angles were mis-reported by six to 21 degrees. Most pre-referral paediatric spine radiographs are inadequate for idiopathic scoliosis evaluation. Standardization of spine imaging and reporting should improve measurement accuracy, facilitate triage and decrease unnecessary radiation exposure

Hip fractures accounts to about 86000 cases per annum in UK. AP and Lateral radiographs form an essential investigation in planning the management of these fractures. Recently it has been suggested that lateral view doesn't provide any additional information in majority of the cases. We looked retrospectively at 25 consecutive radiographs with intracapsular and extracapsular fracture neck of femur each presenting to our department between May 2010 and January 2011. These radiographs were put on the CD in 2 folders as AP and Lateral. It was reviewed by 2 Observers who suggested their preferred treatment. The results were compared for the intra observer agreement to assess the necessity of the lateral view of the radiographs. We also compared the treatment options with the gold standard and looked at the interobserver agreement. Of the 50 set of radiographs that were reviewed, Observer 1 had disagreed with himself on one occasion (98%agreement) compared to the Observer 2 who had two disagreements (96% agreement). When analyzing the intracapsular fractures, we found 100% agreement of OBSERVER 1 with himself when proposing treatment on AP and Lateral View. Whereas, OBSERVER 2 had only one disagreement. It gave us a Free marginal kappa value of more than 0.70 indicating excellent agreement. One difference doesn't have any statistical significance. In the extracapsular fractures, Kappa values ranged from 0.413 to 0.88. OBSERVER 1 did change his opinion after reviewing the lateral view but generally had good outcome (K=0.88). Whereas, the opinion of OBSERVER 2 was unaffected by the Lateral view. The X-ray diagnoses by OBSERVER 1 and OBSERVER 2 had only moderate agreement (K=0.52 (AP) and 0.57 (Lat). Comparing the observer opinion to the gold standard (operation performed) showed moderate agreement both on AP and Lateral view (OBSERVER 1 AP and Lat both K=0.64, OBSERVER 2 AP and Lat both K=0.41). The Lateral view failed to change the opinion of the observers (K > 0.7) but there was moderate to excellent agreement between the observers and observer vs operation (The Gold Standard) with kappa value of more than 0.52. We feel that the Lateral view doesn't make any difference in most of the cases as shown by a good intra-observer agreement. However, we cannot completely rule out their importance and they should be performed in occult fractures, pathological fractures, fractures extending into the shaft, young patients, and on the request of physician

Introduction Thoracic pedicle screws are increasingly being used for internal fixation. Surgeons and radiologists are often required to make decisions about the position of the screws in relation to the pedicle based on AP and lateral plain radiographs alone. We ventured to assess the value of orthogonal radiographs in determining the position of thoracic pedicle screws in 23 cadaveric thoracic vertebrae. Methods Disarticulated cadaveric thoracic vertebrae were used in this study. Pedicle screws were inserted in three positions: 1) within the pedicle, deliberately violating the 2) lateral cortex of the pedicle and 3) medial cortex of the pedicle. AP (antero-posterior) & lateral radiographs were obtained and presented to 6 readers (4 surgeons & 2 radiologists) in booklets consisting of AP views alone, lateral views alone and both AP & lateral views together in a sequential manner. The readers were asked to indicate the position of the screws and the results of the evaluation were compared to the actual position (axial views). Results On AP views alone, the accuracy in detecting screws placed out of the pedicle laterally and medially were 93% and 76% respectively, while the accuracy for screws placed inside the pedicle was 85% . On LATERAL views alone, the accuracy for the same screw positions were 69%, 58% and 64% respectively. When AP + LATERAL views were considered together, the accuracy for the same screw positions were 93%, 80% and 87% respectively. Comparing the three groups, it was observed that screw positions were read more accurately in AP + LATERAL views (87%) compared to AP views alone (85%), or LATERAL views alone (64%). The sensitivity of correctly identifying screws placement is highest in AP + LATERAL (90%) views with a specificity of 94%. The specificity of detecting screws placed inside the pedicle is highest in AP (94%). The positive predictive value (PPV) of radiographs in general (AP +LATERAL) in detecting screws placed inside the pedicle, out of the pedicle laterally and medially were 73%, 92% and 86% respectively. The negative predictive value (NPV) of radiographs in general for the same screw locations were 90%, 96% and 76% respectively. On AP and AP + LATERAL views respectively, 25% and 23% of screws placed inside the pedicle were read as medially ‘out’. 10% of screws placed medially ‘out’ were read as ‘in’ on both AP and AP + LATERAL views. Inter-observer difference was substantial. In general, surgeons appeared to have consistently higher accuracy, sensitivity, specificity, PPV and NPV values compared to radiologists and fellows in determining screw position. Discussion The positions of the screws appear to be most accurately detected when both AP and lateral x-rays are provided compared to AP or lateral alone. Screws that perforated the lateral cortex were the easiest and those that were medially out were the most difficult to identify. Screws passed inside the pedicle may create an unnecessary apprehension that they may be medial and screws passed medially may give a false sense of security that the screw is inside the pedicle. Radiographs are just one component in ensuring accurate pedicle screw placement and surgeon’s experience, in the use of tactile skills and anatomical knowledge continue to be vitally important in the safe placement of thoracic pedicle screws

Introduction. This study investigates and compares the accuracy of pre-operative templating from the AP and lateral radiographs in total knee arthroplasty. Methods. Pre-operative radiographs from 478 patients undergoing primary total knee arthroplasty from September 2006 to April 2009 were reviewed. 154 had digital templating performed on both the AP and lateral radiograph The sizes templated for both the femoral and tibial components were recorded from the PACS archive. These were compared aginst the implanted femoral and tibial sizes taken from the theatre record. A Z-score for two proportions was used to determine the level of significance of any difference in accuracy between the AP and lateral views for each component. Results. The femoral component was templated accurately in 56 cases (36.4%) on the lateral view and in 48 (31.2%) on the AP. It was accurate to within 1 size for the femoral component in 125 cases (81.2%) from both the AP and lateral views. The tibial component was template accurately in 70 cases (45.5%) on the lateral view and in 78 (50.6%) on the AP. It was accurate to within 1 size in 139 cases (90.3%) on the lateral view and in 142 (92.2%) on the AP. The same size was templated for the femoral component in 111 cases (72.1%) and in 83 cases (53.9%) for the tibial component. There was no statistical difference between the AP and lateral templating for either femoral or tibial component. The tibial component was templated significantly more accurately than the femoral component for the exact size (p= 0.016) and to within 1 size (p= 0.007). Conclusions. There is a tendency for greater accuracy of femoral templating on the lateral radiograph and for tibial templating on the AP. Tibial templating is significantly more accurate than femoral templatin

Introduction. To report our early experience and suitability over unicortical fixation system to reduce and hold the bone fragments in position during a CHAOS procedure of the femur or tibia during lower limb reconstruction surgery. Materials and Methods. We report a case series of the first consecutive 10 patients (11 bones) for which this CHAOS technique was used between May 2017 and October 2019 by the same surgeon. The novel aspect of the procedure was the use of a unicortical device, Galaxy UNYCO (Orthofix, Verona, Italy), which eliminate the need for any change of fixation during the procedure. It also means the intramedullary canal was left free for the intramedullary nailing. Results. We treated 4 femurs and 7 tibias with this technique without any loss or failure of the construct. We treated uniplanar and multiplanar deformities with the angulations between 8 degrees of valgus to 15 degrees of varus and from 0 to 8 mm translation in the AP view, from 20 degrees procurvatum to 15 degrees recurvatum and 0 to 2 mm translation on the lateral view and from 20 degrees internal rotation to 5 degrees external rotation and 0 to 10 mm translation on axial view. Conclusions. The construct was able to deal with the total tension in the system both in the correction phase and the additional stress applied during insertion of a nail such as reaming and impacting the nail to the canal. The potential advantage also included the possibility of intramedullary nailing without interference with the external fixation device

Introduction. The functional ante-inclination (AI) of the cup after total hip arthroplasty (THA) is a key component in the combined sagittal index (CSI) to predict joint stability after THA. To accurately predict AI, we deducted a mathematic algorithm between the radiographic anteversion (RA), radiographic inclincation (RI), pelvic tilting (PT), and AI. The current study aims (1) to validate the mathematic algorithm; (2) to convert the AI limits in the CSI index (standing AI ≤ 45°, sitting AI ≥ 41°) into coronal functional safe zone (CFSZ) and explore the influences of the stand-to-sit pelvic motion (PM) and pelvic incidence (PI) on CFSZ; (3) to locate a universal cup orientation that always fulfill the AI criteria of CSI safe zone for all patients or subgroups of PM(PM ≤ 10°, 10° < PM ≤ 30°, and PM > 30°) and PI (PI≤ 41°, 41°< PI ≤ 62°, and PI >62°), respectively. Methods. A 3D printed phantom pelvic model was designed to simulate changing PT values. An acetabular cup was implanted with different RA, RI, and PT settings using robot assisted technique. We enrolled 100 consecutive patients who underwent robot assisted THA from April, 2019 to June, 2019 in our hospital. EOS images before THA and at 6-month follow-up were collected. AI angles were measured on the lateral view radiographs as the reference method. Mean absolute error (MAE), Bland-Altman analysis and linear regression were conducted to assess the accuracy of the AI algorithm for both the phantom and patient radiographic studies. The 100 patients were classified into three subgroups by PM and PI, respectively. Linear regression and ANOVA analysis were conducted to explore the relationship between the size of CFSZ, and PM and PI, respectively. Intersection of the CFSZ was conducted to identify if any universal cup orientation (RA, RI) existed for the CSI index. Results. The mathematic algorithm for calculating AI based on RI, RA, and PT is highly accurate according to the phantom and patient radiographic study. CFSZ size corresponds linearly with PM (R² = 0.638) and PI (R² = 0.129), respectively. There are significant differences in the size of CFSZ, as well as in the intersection of CFSZ and LSZ, between the subgroups of PM and PI, respectively (P<0.017). There is no universal cup orientations could be identified to fulfill the AI limits of the CSI index for all the 100 patients or any of the three subgroups, according to either PM or PI. Conclusions. The cup target orientation should be individualized. The validated algorithm between AI and RA, RI, and PT parameters can serve as the quantitative tool for patient-specific optimization of functional cup AI in different postures

Study Design: A radiographic study using disarticulated cadaver thoracic vertebrae. Objective: To determine the accuracy of orthogonal X-rays in detecting thoracic pedicle screw position by different groups of observers. Summary of Background Data: Pedicle screws are increasingly being used for internal fixation of the thoracic spine. Surgeons and radiologists are often required to make decisions on the pedicle screw position by plain antero-posterior (AP) and lateral radiographs. Materials and Methods: 23 disarticulated fresh adult thoracic vertebrae were used in this study. Pedicle screws were inserted completely within the pedicle; or deliberately violating the lateral or medial cortex of the pedicle. AP and lateral radiographs of each vertebrae were assessed by 2 spine surgeons, 2 spine trainees, and 2 musculoskeletal radiologists in a sequence of AP alone, and AP + lateral views. They were supposed to cataogorize the pedicular screw as ‘out laterally’/‘inside the pedicle’/‘out medially’ or ‘unsure’. Their assessments were compared to the actual position of the screws determined by the axial views. Results: For each screw position, trend was found towards slightly better accuracy with availability of AP & lateral views in combination. From either AP alone or AP + lateral views, significantly higher accuracy was found in detecting screws “out laterally” than “inside pedicle” (p< 0.01), or “out medially”(p< 0.05), respectively. Nearly 30% of screws that were deliberately placed through the medial pedicle wall were not correctly identified. In addition, surgeons have highest accuracy from either AP alone, or AP + lateral views, followed by the spine trainees and radiologists. Radiologists provided more “unsure” answers than surgeons or trainees. Conclusions: Screws that perforated the lateral cortex were the easiest, and those that were wholly within the pedicle were the most difficult to identify correctly. The use of plain radiographs to detect thoracic pedicle screws placed through the critical medial cortex is unreliable. The positions of thoracic pedicle screws appear to be more accurately detected by AP + lateral, however, the major contribution was from AP views. Surgeon experience continues to be vitally important in the safe placement of thoracic pedicle screws. Key points:. Screws that perforated the lateral cortex were the easiest, and those that were wholly within the pedicle were the most difficult to identify correctly. The use of plain radiographs to detect thoracic pedicle screws placed through the critical medial cortex is unreliable. AP + lateral views provides higher accuracy in determining the screw position, while, the major contribution comes from AP views. Surgeon experience, in the use of tactile skills and anatomical knowledge continue to be vitally important in the safe placement of thoracic pedicle screws

Introduction. There is many reports about complications with a resurfacing total hip arthroplasty (RHA). One of the most common complications is the femoral neck fracture. A notch and malalignment were risk factors for this. For an accurate implanting the femoral component in RHA, we performed 3D template and made a patient specific template (PST) using 3D printer and applied this technique for a clinical usage. We report a preliminary early result using this novel technique. material and method. We performed 10 RHAs in nine patients (7 male, 2 female) from June 2009 to March 2010 due to osteonecrosis in 7 hips and secondary osteoarthritis in 3hips with a mean age of 48 years (40-60). We obtained a volumetric data from pre-operative CT and planned using 3D CAD software. Firstly, size of femoral components were decided from the size planning of cups. We aimed a femoral component angle as ten degrees valgus to the neck axis in AP and parallel in lateral view avoiding a notch. We measured femoral shaft axis and femoral neck axis in AP and lateral view using 3D processing software. PSTs were made using Laser Sintering by 3D printer which had the heat tolerance for sterilization in order to insert the femoral guide wire correctly. We operated in postero-lateral approach for all the patients PST has the base (contact part) fit to poterior inter trochanteric area. It has the arm reached from the base and sleeve hole to insert the guide pin into the femoral head. We measured the femoral component angle in three dimensions using the 3D processing software postoperatively. We compared the difference of this angle and the pre-operative planed angles. We also investigated the operation time, the volume of bleeding during operation and complications. Results. The mean femoral neck angle is 131.9±7.2°. The mean femoral component angle in AP view is 142.5±5.4°. The mean femoral component angle in lateral view is 0.1±1.2°. The mean calculated difference in AP view is 3.5±2.8°. And the mean calculated difference in lateral view is 0.9±0.7°. The mean operation time was 120±25 minutes. The mean volume of bleeding was 401±325ml. No major complication was noted. Discussion. By planning three-dimensional, it was possible to make an accurate preoperative planning. Though it is a very preliminary report with a small number of cases, we are encouraged to continue this procedure from this data. An application of PST for implanting femoral component in resurfacing THA brought us an accurate implanting as planned. This technique do not prolong an operation time, cost less and can be done with less invasions compared with a navigation system