Anteroposterior Pelvis X-rays Research Articles

Risk Factors for Trochanteric Bursitis Following Total Hip Arthroplasty: A Radiographic Analysis

BackgroundTrochanteric bursitis (TB) is a prevalent complication following total hip arthroplasty (THA), with increased offset hypothesized as a potential risk factor. This study investigated potential TB predictors in THA patients, including radiographic measurements of offset and leg length, comorbidities, and patient characteristics. MethodsIn this retrospective cohort study, all THA patients from a single academic tertiary care center between 2005 and 2021 were reviewed. Exclusion criteria included less than one-year follow-up, osteonecrosis, or fracture. Manual radiographic measurements of offset (acetabular, femoral, and total) and leg length from preoperative and postoperative antero-posterior pelvis X-rays were taken, with scaling using femoral cortical diameter. Univariable and multivariable Cox proportional hazard models were employed to estimate TB risk. ResultsOf 1,094 patients, 103 (9.4%) developed TB, with a median (Q1, Q3) time to presentation of 41.8 weeks (25.5, 66.9). In univariable models, only sex was associated with increased TB risk, with women exhibiting a 1.79 times increased risk (hazard ratio: 1.79 (1.16, 2.76), P = .009). Changes in acetabular offset, femoral offset, total offset, and leg length between preoperative and postoperative radiographs were not associated with an increased risk of developing TB in the univariate or multivariate models. Furthermore, various offset thresholds were evaluated, with no amount of increased offset showing increased TB risk. ConclusionsThis study found no relationship between femoral, acetabular, or total offset and TB following THA. These findings suggest that surgeons may consider adding offset for increased prosthetic stability in high-risk cases. However, given that this is a retrospective study, the authors are not advocating for the routine use of increased offset. The study identified women as a risk factor with a 1.79 times higher TB risk, highlighting the importance of counseling women patients on this heightened risk.

Acetabular index as an indicator of Pavlik harness success in grade I developmental dysplasia of the hip: A retrospective study.

Some articles have focused on the effectiveness of the Pavlik harness treatment for unstable and dislocated hips, yet data on monitoring its effectiveness with the acetabular index remains elusive. Therefore, this study aimed to assess Pavlik harness effectiveness in infants ≤6 months diagnosed with grade I developmental dysplasia of the hip using acetabular index improvement and identify the possible predictors of successful Pavlik harness treatment. A retrospective review of infants with grade I acetabular dysplasia treated with a Pavlik harness and monitored with anteroposterior pelvis X-rays at presentation and follow-up. Successful treatment was defined as achieving an acetabular index <30°. A total of 231 infants with acetabular dysplasia were treated with a Pavlik harness. A successful outcome was achieved in 135 infants (58.4%). Younger age, lower initial acetabular index, and patients with unilateral developmental dysplasia of the hip were significant predictors of a successful outcome. An age of 4.5 months or older was found to be the threshold for an unsuccessful result following Pavlik harness treatment, with a sensitivity of 65.2% and specificity of 57.3%. An initial acetabular index of 35.5° was found to be the threshold for an unsuccessful result, with a sensitivity of 83.7% and specificity of 61.5%. Pavlik Harness's success in correcting the acetabular index in acetabular dysplasia patients was related to unilateral cases, a younger age at presentation, and a lower initial acetabular index. The thresholds for unsuccessful treatment were an age of 4.5 months or greater and an acetabular index of 35.5° or higher.

Contemplate iliosacral screw in patients with developmental dysplasia of the hip

ObjectivesOur aim in the study was evaluating sacroiliac morphology in patients with DDH and its possible effect on appropriate iliosacral screw fixation.DesignRetrospective cohort study.SettingLevel of evidence 3.Patients/participantsWe evaluated the anteroposterior pelvis X-ray and pelvic CT scans of patients. We mainly divided the patients into two groups: DDH group (n:105) and control group (n:105).InterventionThe presence of the five qualitative characteristics of sacral dysplasia evaluated according to Route in both groups. The DDH group was divided into four subgroups according to the degree of hip dysplasia.Main outcome measurementThe cross-sectional area, length of the osseous corridor, coronal and vertical angulation evaluated in both groups.ResultsThe DDH group also exhibited a significantly higher S1 coronal and axial angulation, lower S1 cross-sectional area and S1 iliosacral screw length than the control group (p:0.033, p:0,002, p:0.006, p:0,019, respectively). According to the Rout classification, 9% were normal, 31% transient, 58% dysplastic in the DDH group. 45.7% were normal, 38% transient, 17% dysplastic in the control groups. These differences between the groups were statistically significant (p < 0.001). When the DDH groups were evaluated within themselves; no statistically significant difference was observed in S1 and S2 cross-sectional area, S1 and S2 maximum estimated iliosacral screw length, S1 and S2 axial and coronal angles assessment.ConclusionSacral dysplasia was more common, narrower and more angled osseous canal for the iliosacral screw was found in the DDH group. There was no relation between the degree of hip dysplasia and sacrum morphology in the DDH group. Thus, we suggest the surgeons be aware of iatrogenic injury even in constrained dysplastic hips.

Comparison of a Minimally Invasive Tissue-Sparing Posterior Superior (TSPS) Approach and the Standard Posterior Approach for Hip Replacement.

Purpose The purpose of this study is to compare the functional and clinical outcomes, blood loss, complication rate, and hospital length of stay (LOS) of total hip replacement (THR) using a minimally invasive tissue-sparing posterior superior (TSPS) approach and the standard posterior approach. Materials and Methods This retrospective, observational, double-centered study included 38 patients undergoing hip replacement. The patents were divided into two groups: control group (19 patients), who underwent surgery with the standard posterior approach, and treatment group (19 patients), who received the same type of implant with ceramic-on-ceramic bearing via the TSPS approach. Hemoglobin level was assessed preoperatively, on first and second postoperative days, and on discharge day. Harris hip score and Western Ontario and McMaster Universities Arthritis Index were used to measure the clinical and functional outcomes. Hospital LOS and incidence of early and late complications were assessed in both groups. Postoperative anteroposterior pelvis X-ray was performed to assess the correct positioning of implants. Results Better early clinical outcomes (p = 0.0155), lesser blood loss (p < 0.0001), and reduced hospital LOS (p < 0.0001) were observed in the TSPS group than in the control group. No major adverse effects occurred in both groups, and a satisfactory implant orientation was achieved in all patients. Conclusions The TSPS approach is a reliable minimally invasive procedure for THR as it allows an accurate orientation of the components and provides better early postoperative functional outcomes, faster recovery, significantly lower blood loss, and shorter hospital LOS than the standard posterior approach. However, further research is needed to confirm the promising results and cost-effectiveness of the TSPS approach in larger cohorts with a longer follow-up period.

Translated article] Correlation between femoral version and severity of hip dysplasia in patients with advanced osteoarthritis prior to total hip arthroplasty

IntroductionDevelopmental dysplasia of the hip (DDH) is a condition which comprises a number of joint abnormalities, including modifications in femoral version and neck-shaft angle (CCD), as well as a probable progression to osteoarthritis in certain cases. The main objective of this research was to find a correlation between femoral version and severity of DDH in patients with advanced osteoarthritis prior to joint replacement, which has not been previously reported. A secondary aim was to describe the modification of CCD as the severity of DDH increases. Materials and methodPatients over the age of 15 with dysplastic hips and severe osteoarthritis prior to total hip arthroplasty were assessed between March 2018 and February 2019. Cases with any previous hip surgery were excluded. Anteroposterior pelvis X-rays and femoral computed tomography (CT) were performed; femoral version was measured in CT and CCD was evaluated both in X-rays (2 observers: A and B) and CT (one observer: musculoskeletal radiologist). Severity of DDH was defined by observers A and B according to Crowe classification in X-rays. Statistical analysis was performed on SPSS v.21. Shapiro–Wilk test was used to confirm a normal data distribution. Intraclass correlation coefficient (ICC) determined the level of agreement between observers A and B. Pearson test assessed the correlation between femoral version and Crowe classification (positive if >0.5). Student's t test evaluated the statistical significance, which was defined as P<0.05. ResultsOne-year assessment; 42 patients (54 hips), 76% women. Mean age 52.7 years. 45 hips completed the imaging set, 9 hips were assessed only with X-rays. 48%, 16%, 7% and 28% were classified as Crowe I, II, III and IV (100% interobserver agreement). Crowe classes were grouped as I, II/III and IV due to a low number of cases classified as II and III. Mean femoral version was 21.73°, 26.8° and 43.58°, respectively. ICC between observers A and B for CCD measured in X-rays was 0.96. Mean CCD measured in X-rays for each group (I, II/III and IV) was 148.11°, 147.7° and 147°, and in CT was 131.21°, 127.9° and 122.14°, respectively. A significant difference was found in femoral version between groups I and IV (P=0.0002) and II/III and IV (P=0.042). Pearson correlation between femoral version and severity of DDH was positive (r=0.52; P=0.0002). A significant difference between CCD measured in CT was found between groups I and IV (P=0.003). ConclusionsA significant increase in femoral version related to severity of DDH and a positive correlation between these 2 features were found. Furthermore, a significant decrease in CCD between groups I and IV measured in CT was revealed. These findings would be helpful for preoperative planning of total hip replacement in osteoarthritis secondary to DDH, because once the surgeon has assessed the severity of DDH on X-rays or CT, an increased femoral version could be expected. Therefore, availability of specific implants such as conic, modular or cemented stems is critical, in order to modify the femoral anteversion to normal values in the most severe cases.

Prospective comparative study of quantitative X-ray (QXR) versus dual energy X-ray absorptiometry to determine the performance of QXR as a predictor of bone health for adult patients in secondary care

ObjectivesTo evaluate a method of quantitative X-ray (QXR) for obtaining bone health information from standard radiographs aimed at identifying early signs of osteoporosis to enable improved referral and treatment. This...

Applying the Hip-Spine Relationship: What X-Rays and Measurements Are Important?

Understanding spinopelvic motion and the dynamic relationship of the hip, spine, and pelvis is essential in decreasing the risk of instability after total hip arthroplasty. The hip-spine relationship is complex, and a detailed analysis of each patient’s spinopelvic mobility is warranted to help guide safe acetabular component positioning. Through the use of a standing anteroposterior pelvis X-ray, lateral spinopelvic radiographs in the standing and seated position, and advanced functional imaging, key spinopelvic parameters can be obtained. A systematic preoperative workup can help to identify hip-spine pathology that predisposes patients to instability, and can help in planning and establishing a patient-specific “safe zone.” Based on the presence of concomitant hip-spine pathology, patients must be evaluated thoroughly with preoperative imaging to plan for the optimal target acetabular cup position. This paper guides readers through important parameters and imaging associated to spinopelvic motion as it relates to total hip arthroplasty stability.

Hip hemiarthroplasty with modular neck: is it useful in residents' learning curve? A prospective clinical trial.

The number of femoral neck fractures (FNFs) worldwide will drastically increase in the next few decades, reaching 6.3 million by 2050. In the future, therefore, newly-qualified orthopaedic surgeons will treat this kind of injury more frequently than in past decades. This prospective observational study aims to assess whether hip hemiarthroplasty with modular neck, performed via the Hardinge approach, can be safely carried out by orthopaedic residents. Patients referred to our Level I trauma centre, between January 2016 and June 2017, with displaced intra-articular femoral fractures, were prospectively recruited. All patients underwent cemented modular bipolar hip hemiarthroplasty (Profemur Z, MicroPort Orthopedics Inc., Arlington, TN, USA) via the Hardinge approach, with the patient positioned in lateral decubitus. The surgical procedures were performed by the same surgical and anesthesiology team, under spinal anaesthesia. All patients underwent clinical and radiographic follow-up up to 24 months. Complications and re-operations were recorded. Clinical evaluation was performed using the Harris Hip Score (HHS), Osteoporosis Quality of Life Questionnaire QUALEFFO-41 and EuroQol-5D (EQ-5D) questionnaire. Anteroposterior pelvis x-rays were performed preoperatively, postoperatively and at 1, 3, 6, 12 and 24 months follow-up. 118 patients met the inclusion criteria (male: 50; female: 68; mean age: 74.3 years; range 65-88 years) and were included in the current study. 67 patients out of 118 (56.8%) were managed by senior orthopaedic surgeons (Group A), whereas the remaining 51 patients out of 118 (43.2%) were treated by orthopaedic residents (Group B). Hip hemiarthroplasties performed by senior surgeons showed the prevalent use of straight (short or long) necks, whereas, in surgical procedures performed by residents, there was a significantly higher use of varus/valgus, anteverted or retroverted necks. The overall complication rate was significantly higher in Group-B patients, compared with Group-A patients (p = 0.002). The length of hospital stay and the mean clinical scores at 24 months follow-up showed no significant differences. Hip hemiarthroplasty with modular neck can be safely employed during the learning curve of orthopaedic residents. Great efforts, however, should be made in future to improve residents' training in the management of FNFs.

Association of Subpubic Angle Measurement with Age and Gender in a Group of Adult Sudanese Patients

Background: The measurement of the subpubic angle (SPA) has been used for determining gender with a high degree of accuracy in various ethnic groups. This measurement can also be helpful in forensic and physical anthropology. The aim of this study was to compare the SPA in different adult age groups (males and females) and to use the SPA to estimate the demarking point (DP) for the determination of gender. Methods: This study included 158 subjects – 59 male and 99 female. The SPA was measured electronically using antero-posterior pelvis X-rays. Measurements were taken retrospectively using the Picture Archiving and Communication System. SPA measurements were compared between the male and female participants in different adult age groups. To determine the gender, the DP was calculated from the means of SPA in male and female participants. Results: A comparison of the means of SPA between males and females showed that females (134.94 ± 15.33º) had wider SPA than males (105.88 ± 10.33) with a significant difference (P = 0.012). While a DP &gt; 126.5 is most likely indicative of a female pelvis, a DP &lt; 104.3 is indicative of a male pelvis. The accuracy levels based on the measured DP of participants in this study were 45.8% and 69.7% for males and females, respectively. Besides, with regards to age, the mean values for different age groups in males and females were statistically insignificant (P-values were 0.21 and 0.75, respectively). Conclusions: According to the obtained results, the variations in the measurements of the SPA from pelvic X-rays can be used to determine gender. The calculated SPA range and DP were found to predict female gender with higher accuracy. Age was not associated with any notable differences in SPA measurements. Keywords: subpubic angle, pelvis, Sudanese, sex differences

Evaluation of version of acetabular component following total hip replacement on conventional radiograph and computed tomography

Background/Purpose: Total hip replacement (THR) is considered as one of the most successful orthopedic procedures. However, improperly placed components can lead to instability and accelerated wear. Acetabular cup inclination can be very well accessed by anteroposterior pelvis X-rays; for acetabular version assessment, computed tomography (CT) scan is the gold standard. CT scan is not readily available at many centers and the surgeon has to rely on X-ray methods for evaluation of acetabular version to audit results and to predict behavior of the surgical intervention. This prospective study was undertaken to compare Woo and Morrey’s and ischiolateral methods of assessment of acetabular version on cross-table lateral radiographs with CT assessment and to assess the validity of radiographic methods with respect to CT scan method. Material and methods: A prospective follow-up study was conducted for 18 months’ duration (October 2016 to March 2018) on 30 adult patients who underwent THR surgery. Cross-table lateral radiograph was obtained at 3 and 6 weeks in the postoperative period. Two observers made each observation at two different points of time. CT scan was performed at 3 weeks. Version as measured by radiographs and CT scan was recorded. Results: The major overlap in the distribution of the values of the Woo and Morrey method suggests that there is no significant difference between the observations. Distribution of the values of the ischiolateral view and the CT scan value distributions have a very small overlap and hence suggest a strong significant difference between the two. Conclusion: In this study, Woo and Morrey’s method and ischiolateral method of assessment of acetabular version were compared with CT assessment. We found that in Woo and Morrey’s method, values were comparable to CT scan values, when put on regression line. However, in situation of change in patient positioning, namely hip stiffness in contralateral hip, measurement of component changed in series of radiography due to differences in pelvis tilt. So, in these circumstances, we can use ischiolateral method which can give consistent measurement. But it will not be in concordance with CT scan values and Woo and Morrey values, as represented in regression line. The high intra-class correlation coefficients for both intra- and inter-observer reliability indicated that the angle measured with these methods is consistent and reproducible for multiple observers. CT, however, be considered as gold standard for measurement owing to control over pelvic rotation and/or tilt/patient positioning.

Surgical implications of the hip-spine relationship in total hip arthroplasty.

Total hip arthroplasty (THA) is considered the most successful orthopedic surgical procedure of the last century with excellent survivorship up to 20-years. However, instability remains a major issue representing the most common reason for revision after THA. Hip-spine relationship has gained progressive interest between arthroplasty surgeons and its understanding is crucial in order to identify high-risk patients for postoperative dislocation. Spinal deformity and abnormal spinopelvic mobility have been associated with increased risk for instability, dislocation and revision THA. Preoperative workup begins with standing anteroposterior pelvis x-ray and lateral spinopelvic radiographs in the standing and sitting position. Hip-spine stiffness needs to be addressed before THA in consideration of adapting the preoperative planning to the patient’s characteristics. Acetabular component should be implanted with different anteversion and inclination angles according to the pattern of hip-spine motion in order to reduce the risk of impingement and consequent dislocation. Different algorithmic approaches have been proposed in case of concomitant hip-spine disease and in case of altered sagittal balance and pelvic mobility. The aim of this review is to investigate and clarify the hip-spine relationships and evaluate the impact on modern total hip arthroplasty.

Low back pain and radiographic severity as predictors in hip osteoarthritis patients receiving steroid injection therapy.

We investigated the effects of lower back pain (LBP) on measures of pain, disability, and function in highly symptomatic hip OA patients receiving intra-articular steroid injection (IASI) therapy. We also investigated the effect of radiographic severity of hip OA for comparison to LBP. 97 consenting subjects with symptomatic hip OA presenting for IASI were evaluated at baseline, assessed over an 8-week period, and followed at least 1 year later for new arthroplasty. At baseline and 8 weeks follow-up patient demographics, presence/absence of back pain, physical function tests, a single anteroposterior pelvis x-ray, and subjective scores of pain, stiffness and function (VAS and WOMAC) were collected. We also followed which subjects proceeded to obtain total hip arthroplasty in the examined hip. Cohorts with LBP reported significantly worse scores for all of VAS pain and WOMAC questionnaires but showed no difference in ROM and were not more likely to proceed to arthroplasty. Cohorts with severe radiographic OA had significantly worsened scores for stiffness (χ2 = 6.74, p = 0.009), decreased ROM (p < 0.01), and were more likely to proceed to arthroplasty (χ2 = 9.79, p = 0.044). Back pain has a substantial effect on clinical parameters relevant to assessment of severity of hip OA, especially self-reported pain and function. This finding highlights LBP as a significant confounding factor in hip OA patient assessments and will inform future studies to determine the most effective treatment strategies for hip OA patients.

Semi-automated longitudinal assessment of quantitative joint space width at the hip in a community-based cohort

Purpose: Computer-assisted quantitative joint space (qJSW) measurements may provide a more accurate measurement of hip joint width and help identify other risk factors for hip OA. The aim of this study was to characterize qJSW over time in the Johnson County Osteoarthritis Project (JoCo OA), overall and by incident radiographic and symptomatic hip OA. Methods: The JoCo OA is a longitudinal study of civilian, non-institutionalized African American and white men and women greater than 45 years old at baseline who were residents of one of six designated townships in Johnson County for at least one year. For this analysis, we selected individuals with anteroposterior pelvis x-rays from baseline and 3 follow up time points, approximately 6 years apart. Per protocol, women under 50 years old did not have pelvis radiography. All hips were assigned a Kellgren-Lawrence grade (KLG) by an expert musculoskeletal radiologist (JBR). At all time points, participants were asked about the presence of hip symptoms (On most days, do you have pain, aching, or stiffness in your (right, left) hip?”). Incident radiographic hip radiographic OA (rHOA) was defined as KLG 2 or more at follow up (among those without rHOA at baseline), while incident symptomatic hip OA (sxHOA) required both rHOA and symptoms in the same hip. QJSW measurements were performed at 3 locations on each hip radiograph: 10, 30 and 50 degrees with respect to an anatomical landmark. Assessment was performed using a previously described method by an independent reader (JD) blinded to other radiographic or clinical information (Figure 1). With qJSW as the outcome over time from baseline, longitudinal mixed models (LMM) for each angle were stratified by sex, adjusted for continuous age, height, BMI, time, and categorical weight gain or loss (defined as a 5% change in BMI) to estimate model-based fixed effects (using restricted maximum likelihood); additional stratification by incident rHOA or sxHOA was also performed. LMM were assessed at the hip level with an unstructured covariance matrix, accounting for random effects at the participant level (intercept and time) and at the hip level (intercept). Results: There were 577 participants with 1154 hip x-rays meeting the above criteria; after exclusion of those missing hip films or with hip replacement, 397 participants and 784 hips were analyzed (59% women, 24% African American, average baseline age 57.5 for women and 55.2 for men). The overall incidence of rHOA and sxHOA was about 20% and 12%, respectively. In men, qJSW at the 10, 30, and 50 degree measurements did not vary significantly with time; in general, qJSW was wider with increasing height in males. In women, compared to 10 and 30 degrees, the qJSW measurements at 50 degrees were more sensitive to change over time and are discussed below and shown in Figure 2. As shown in Figure 2 A-B, taller women had greater qJSW although this declined with age. Taller women (e.g., at a representative value of 165cm) with higher BMI (here, at a representative value of 34 kg/m2) had more significant narrowing if they gained weight compared with those that maintained weight. Women with normal BMI (24 kg/m2) at the same height (165cm) had a similar decrease in qJSW regardless of gaining or maintaining weight. Shorter women (155cm) who were obese (34 kg/m2) had a decline in qJSW regardless of change in weight. However, shorter women (155cm) with average BMI (24 kg/m2) showed a significant decrease in qJSW if they maintained weight compared to those that gained weight. As shown in Figure 2 C-D, women who developed HOA according to KLG criteria had significantly narrower qJSW at baseline (this was also true for men, data not shown) and greater loss over time than those who did not develop HOA. Conclusions: In this community-based cohort, sex differences were observed in qJSW measurements of the hip, suggesting that qJSW changes over time may not be as sensitive in males, potentially due to anatomical differences in men and women. In women, the 50 degree measurements appear to be the most sensitive, and the impact of gaining or maintaining weight appeared to vary based on height. At 50 degrees in both men and women, rHOA and sxHOA were strongly associated with a narrower qJSW, suggesting that qJSW may prove to be a valid measurement tool.

Ultrasound Is an Alternative to X-ray for Diagnosing Developmental Dysplasia of the Hips in 6-Month-Old Children.

Infants previously treated for developmental dysplasia of the hips (DDH) are routinely imaged with ultrasound initially and reimaged with an anteroposterior (AP) pelvis X-ray at 6months of age to assess for dysplasia. It has become convention to transition from ultrasound to AP X-ray at 6months of age, but no study has demonstrated that ultrasound is inadequate at this age. The purpose of this study was to confirm that ultrasound for the 6-month DDH evaluation is a feasible alternative to the standard X-ray. Thirty-one 5- to 7-month-old infants undergoing AP pelvis X-ray related to previous Pavlik harness treatment for DDH or to a history of breech presentation were prospectively enrolled. All patients were imaged with an AP pelvis X-ray and bilateral hip ultrasounds. Three senior orthopedic surgeons unfamiliar with the patient histories evaluated both types of imaging for standard measures of hip dysplasia, including acetabular index (AI), alpha angle, and bony rim percent coverage of the femoral head. Pearson correlation coefficients were calculated for the X-ray and ultrasound measures. Good quality ultrasound images were obtained in all patients, despite the presence of the ossific nucleus in 66% of the hips. All three reviewers correctly diagnosed the one dislocated hip via both X-ray and ultrasound. There were no false negatives on ultrasound, and none of the patients with negative ultrasounds required treatment during the mean 26months of follow up. An increased AI on X-ray was correlated with lower percent coverage of the femoral head on ultrasound. Ultrasound is a technically feasible DDH imaging modality that can be used as an alternative to X-ray for 6-month-olds.

A Preoperative Workup of a “Hip-Spine” Total Hip Arthroplasty Patient: A Simplified Approach to a Complex Problem

BackgroundA large body of evidence has confirmed that patients with spinal deformity, lumbar fusion, and abnormal spinopelvic mobility are at significantly increased risk for instability, dislocation, and revision after total hip arthroplasty (THA). MethodsAchieving a stable construct in patients with pre-existing spine disease requires an understanding of basic spinopelvic parameters and the compensatory mechanisms associated with abnormal spinopelvic motion. Indicated patients with concomitant hip-spine pathology should be assessed for (1) the presence of spinal deformity and (2) the presence of spinal stiffness before undergoing THA. Preoperative imaging should include a standing anteroposterior pelvis x-ray, as well as two lateral spinopelvic radiographs in the standing and seated position. ResultsBased on the presence of spinal deformity and/or spinal stiffness, patients may be categorized as one of the four groups of the “Hip-Spine Classification in THA.” A series of illustrative case examples is provided. ConclusionA simple three-step assessment with minimal measurements will effectively identify the complex “hip-spine” THA patient at high risk for postoperative instability. Adhering to group-specific recommendations for acetabular cup position can help to further reduce the burden of instability and related revisions in this challenging population.

Variability of Pelvic Orientation in the Lateral Decubitus Position: Are External Alignment Guides Trustworthy?

BackgroundThe position of the acetabular component in total hip arthroplasty (THA) is critical for success. However, this remains the most variable aspect of the surgery. We hypothesized that there is wide variation in pelvic orientation in the lateral decubitus position. We sought to determine the variability in pelvic positioning and the frequency of pelvic malposition during THA in lateral decubitus with regard to pelvic tilt and pelvic rotation. MethodsWe analyzed preoperative standing and intraoperative anteroposterior pelvis X-rays in 248 consecutive THAs performed in lateral decubitus by one surgeon. Pelvic tilt and rotation were determined for preoperative and intraoperative X-rays. Proper intraoperative positioning was defined as less than 10° change in tilt or rotation between preoperative and intraoperative X-rays. ResultsWith regard to pelvic tilt, the intraoperative position was proper in 188 (76%) cases. There was a pelvic tilt discrepancy of 10°-20° in 43 (17.5%) cases and greater than 20° in 16 (6.5%) patients. With regard to pelvic rotation, the intraoperative position was proper in 202 (81%) cases. There was a pelvic rotation discrepancy of 10°-20° in 38 (15.4%) cases and greater than 20° in 7 (2.8%) cases. In 248 cases, only 154 (62.1%) had intraoperative positioning within 10° of preoperative tilt and axial rotation. Pelvic malposition occurred in 38% of cases overall. ConclusionThere is wide variation in pelvic orientation in lateral decubitus and frequent discrepancy in pelvic tilt and rotation between preoperative and intraoperative anteroposterior X-rays. Anatomic landmarks should be used to guide acetabular component positioning. Level of Evidence IIIDiagnostic.

Pre-surgery evaluations by telephone decrease travel and cost for families of children with cerebral palsy.

Introduction:Children with cerebral palsy need highly specialized care. This can be very burdensome for families, particularly in large rural states, due to the need for long-distance travel to appointments. In this study, children undergoing the selective percutaneous myofascial lengthening surgery utilized a telephone-based telemedicine evaluation to assess for surgical eligibility. The goal was to avoid a separate preoperative clinic visit weeks before the surgery. If possible, eligibility was determined by telephone, and then, the patient could be scheduled for a clinic visit and possible surgery the next day, saving the family a trip. The purposes of the study were to calculate estimated reductions in miles traveled, in travel expenses, and in carbon emissions and to determine whether the telephone assessment was accurate and effective in determining eligibility for surgery.Methods:From 2010 to 2012, 279 patients were retrospectively reviewed, and of those, 161 mailed four-page questionnaire and anteroposterior pelvis X-ray followed by a telephone conference. Geographic information system methods were used to geocode patients by location. Savings in mileage and travel costs were calculated. From 2014 to 2015, 195 patients were additionally studied to determine accuracy and effectiveness.Results:The telephone prescreening method saved 106,070 miles in transportation over 3 years, a 38% reduction with US$55,326 in savings. Each family saved an average of 658 (standard deviation = 340) miles of travel and US$343.64 (standard deviation = US$178) in travel expenses. For each increase of 10 miles in distance from the health center, the odds of a patient utilizing telephone screening increased by 10% (odds ratio: 1.101, 95% confidence interval: 1.073–1.129, p < 0.001). After the telephone prescreening, 86% were determined to be likely candidates for the procedure. For 14%, a clinic visit only was scheduled, and they were not scheduled for surgery.Conclusion:Families seeking specialized surgical care for their disabled children particularly benefited from this approach.

Successful Pavlik Harness Treatment for Developmental Dysplasia of the Hip and Normal X-Ray at the Age of 2 Years: Is a Longer Follow-up Necessary?

Management of developmental dysplasia of the hip (DDH) with a Pavlik harness is a well-known treatment.Follow-up until skeletal maturity is recommended as long-term studies mention late sequelae.The purpose of this study was to determine whether such a follow-up is necessary in patients treated successfully under a strict protocol. A retrospective review of a consecutive series of normal infants treated for DDH between January 1995 and July 2004 was undertaken.Only normal infants with frankly pathologic hips treated successfully with a Pavlik harness were included, and with a normal anteroposterior (AP) pelvis x-ray at the age of 2 years.All infants with any type of neurological disease, syndrome, other form of treatment for DDH, and failure of the Pavlik harness were excluded.At the last follow-up, a clinical examination and a standing AP pelvis x-ray were performed. A total of 109 hips in 83 children were available for review. The mean follow-up was of 10 years and 2 months. All 109 hips had a normal clinical examination and a normal AP pelvis x-ray: a mean center-edge angle (CEA) of 29.5 degrees, SD±4.1 degrees, a mean acetabular index (AI) of 1457±3.74 degrees, a mean Sharp's angle of 41.92±3.42 degrees, a Seringe-Severin score of IA, a normal teardrop figure, no signs of avascular necrosis, and Moses circles <2. This study strongly suggests that in a selected group of patients treated for DDH with a Pavlik harness, under a strict protocol, and a normal x-ray at 2 years of age, a long-term follow-up is not necessary. Level III-therapeutic.

2015

Acetate templating for total hip arthroplasty (THA) is cumbersome and inaccurate. High cost hampers mainstream use of digital templating despite ease of use and accuracy. The aim of this study was to validate a low-cost digital THA templating system. Low-cost digital templating software was created using C# programming language. On the basis of power calculations, three surgeons templated 20 consecutive anteroposterior pelvis X-rays using this software against an industry standard. Intraclass correlation coefficient for both systems was approximately .90 for component size and femoral neck cut position. Bland-Altman plots demonstrated that both systems predicted actual implant size with similar accuracy. Interrater reliability was not significantly different between the two systems. This low-cost digital THA templating system is up to 12-fold lower in cost than currently available software with similar accuracy.

Fully automatic segmentation of AP pelvis X-rays via random forest regression with efficient feature selection and hierarchical sparse shape composition

In clinical practice, traditional X-ray radiography is widely used, and knowledge of landmarks and contours in anteroposterior (AP) pelvis X-rays is invaluable for computer aided diagnosis, hip surgery planning and image-guided interventions. This paper presents a fully automatic approach for landmark detection and shape segmentation of both pelvis and femur in conventional AP X-ray images. Our approach is based on the framework of landmark detection via Random Forest (RF) regression and shape regularization via hierarchical sparse shape composition. We propose a visual feature FL-HoG (Flexible-Level Histogram of Oriented Gradients) and a feature selection algorithm based on trace radio optimization to improve the robustness and the efficacy of RF-based landmark detection. The landmark detection result is then used in a hierarchical sparse shape composition framework for shape regularization. Finally, the extracted shape contour is fine-tuned by a post-processing step based on low level image features. The experimental results demonstrate that our feature selection algorithm reduces the feature dimension in a factor of 40 and improves both training and test efficiency. Further experiments conducted on 436 clinical AP pelvis X-rays show that our approach achieves an average point-to-curve error around 1.2mm for femur and 1.9mm for pelvis.