Assessment Of Total Hip Arthroplasty Research Articles

The variability of CT scan protocols for total hip arthroplasty: a call for harmonisation

CT is the principal imaging modality used for the pre-operative 3D planning and assessment of total hip arthroplasty (THA). The image quality offered by CT has a radiation penalty to the patient. Higher than necessary radiation exposure is of particular concern when imaging young patients and women of childbearing age, due to the greater risk of radiation-induced cancer in this group. A harmonised low-dose CT protocol is needed, evidenced by the huge variability in the 17 protocols reviewed. The majority of the protocols were incomplete, leading to uncertainty among radiographers when performing the scans. Only three protocols (20%) were optimised for both ‘field of view’ and image acquisition parameters. 10 protocols (60%) were optimised for ‘field of view’ only. These protocols included imaging of the relevant landmarks in the bony pelvis in addition to the knees – the reference for femoral anteversion. CT parameters, including the scanner kilovoltage (kV), milliamperage–time product (mAs) and slice thickness, must be optimised with a ‘field of view’ that includes the relevant bony landmarks. The recommended kV and mAs values were very wide ranging from 100 to 150 and from 100 to 250, respectively. The large variability that exists amongst the CT protocols illustrates the need for a more consistent low-dose CT protocol for the planning of THA. This must provide an optimal balance between image quality and radiation dose to the patient. Current CT scanners do not allow for measurements of functional pelvic orientation and additional upright imaging modalities are needed to augment them.

Comparative outcome assessment of total hip arthroplasty versus bipolar hemiarthroplasty in intracapsular neck of femur fracture in old age

Background: This prospective study aimed to compare the outcomes of total hip replacement (THR) and bipolar hemiarthroplasty for the treatment of displaced femoral neck fractures in elderly patients. Methods: A total of 30 patients aged over 60 years with femoral neck fractures were included in the study, with 15 patients receiving a bipolar prosthesis and patients receiving THR between June 2021 and January 2023. The patients were followed up for 6 months postoperatively, with functional analysis conducted using the modified Harris hip score. Results: The results showed that the modified Harris hip score was significantly higher in the THR group compared to the bipolar prosthesis group at day 1, 3, 6 and 12 months postoperatively. Pain levels were similar between the two groups at all follow-up intervals. Gait and range of motion were significantly higher in the THR group compared to the bipolar prosthesis group at all-time points. Conclusions: Based on the short-term functional outcomes of this study, THR appears to be a preferable option over bipolar prosthesis for managing femoral neck fractures in elderly.

Functional assessment of total hip arthroplasty using inertial measurement units: Improvement in gait kinematics and association with patient-reported outcome measures.

Inertial measurement units (IMUs) are commonly used for gait assessment, yet their potential for quantifying improvements in gait function and patterns after total hip arthroplasty (THA) has not been fully explored. The primary aim of this study was to compare spatiotemporal parameters and sagittal plane kinematic patterns of patients with hip osteoarthritis (OA) before and after THA, and to asymptomatic controls. The secondary aim was to assess the association between dynamic hip range of motion (ROM) during walking and the Hip Osteoarthritis Outcome Scores (HOOS). Twenty-four patients with hip OA and 24 matched asymptomatic controls completed gait analyses using the RehaGait® sensor system. Patients were evaluated pre- and 1 year postoperatively, controls in a single visit. Differences in kinematic data were analyzed using statistical parametric mapping, and correlations between dynamic hip ROM and HOOS were calculated. Walking speed and stride length significantly increased (+0.08 m/s, p = 0.019; +0.06 m, p = 0.048) after THA but did not reach the level of asymptomatic controls (-0.11 m/s, p = 0.028; -0.14 m, p = 0.001). Preoperative hip and knee kinematics differed significantly from controls. After THA, they improved significantly and did not differ from controls. Dynamic hip flexion-extension ROM correlated positively with all HOOS subscores (r > 0.417; p ≤ 0.001). The change in HOOS symptoms in patients was explained by the combination of baseline HOOS symptoms and change in dynamic hip ROM (r2 = 0.748) suggesting that the additional information gained with IMU gait analysis helps to complement and objectify patient-reported outcome measures pre- and postoperatively and monitor treatment-related improvements.

Development of an open-source measurement system to assess the areal bone mineral density of the proximal femur from clinical CT images.

For existing CT images acquired for various reasons other than osteoporosis, it might be beneficial to estimate areal BMD as assessed by dual-energy X-ray absorptiometry (DXA-based BMD) to ascertain the bone status based on DXA. In this study, we aimed to (1) develop an open-source reproducible measurement system to quantify DXA-based BMD from CT images and (2) validate its accuracy. This study analyzed 75 pairs of hip CT and DXA images of women that were acquired for the preoperative assessment of total hip arthroplasty. From the CT images, the femur and a calibration phantom were automatically segmented using pre-trained codes/models available at https://github.com/keisuke-uemura . The proximal femoral region was isolated by manually selected landmarks and was projected onto the coronal plane to measure the areal density (CT-aHU). The calibration phantom was employed to convert the CT-aHU into CT-aBMD. Each parameter was correlated with DXA-based BMD, and the residual errors of CT images to estimate the T-scores in DXA were calculated using the standard error of estimate (SEE). The correlation coefficients of DXA-based BMD with CT-aHU and CT-aBMD were 0.947 and 0.950, respectively (both p < 0.001). The SEE for quantifying the T-scores in DXA were 0.51 and 0.50 for CT-aHU and CT-aBMD, respectively. With the method developed herein, CT permits estimation of the DXA-based BMD of the proximal femur within the standard DXA total hip region of interest with an SEE of 0.5 in T-scores. The radiation dose for CT acquisition needs consideration; therefore, our data do not provide a rationale for performing CT for screening osteoporosis. However, on CT images already acquired for clinical indications other than osteoporosis, researchers may use this open-source system to investigate osteoporosis status through the estimated DXA-based BMD of the proximal femur.

Radiological assessment of total hip arthroplasty in displaced neck of femur fracture: An observational study

Aim: Radiological assessment of Total Hip Arthroplasty in Displaced fracture Neck of femur. Materials and Methods: This observational study was carried out in the Department of Orthopaedics, American International Institute of Medical Sciences, Udaipur, Rajasthan, India. Total 110 patients were treated with total hip replacement. Plain X-ray pelvis with both hip joints and proximal femur - pre and post-operative - AP view, preoperative X-ray of affected hip- lateral view, X-ray of the operated hip with proximal 2/3rd of femur- AP and lateral view were evaluated. Results: Out of 110, 80 patients were male and 30 female. Most of the patients in this study were above 60 year, followed by 55-60 year. Patients scored 47.3% excellent, 27.3% good, 10.9% fair and 14.5% poor. The acetabular cup inclination 85 neutral, 15 vertical and 10 horizontal positions were seen. Femoral stem positions were central in 82 hips, valgus in 15 hips and varus in 13 hips. There were 2 subsidences and 1 migration. Class II heterotopic ossification was noted in 4 hips, i.e., 6% incidence that underwent THA. We had 2 cases of dislocation (1.8%). Conclusion: The result of this study shows that Total Hip Arthroplasty gave good results in Displaced Intracapsular Neck of femur fractures with radiological assessment.

Assessment of total hip arthroplasty as a predisposing factor for ischiofemoral impingement.

To examine the effect of total hip arthroplasty (THA) on ischiofemoral (IF) and quadratus femoris (QF) spaces with the hypothesis that THA does not affect ischiofemoral relationships. The study was IRB approved and complied with HIPAA guidelines. We identified consecutive MR examinations (pelvis and/or hip) obtained at our institution in adults (≥18years old) screened for THA-related complications. Native hips from the same individuals served as controls. We collected medical record data including age, gender, surgical history, and THA designs. Two radiologists independently measured the IF-RAD and IF-MRI (IF space on radiographs and MR imaging, respectively) and QF space (on MR imaging). Groups were compared using ANCOVA controlled for gender. The study group comprised 250 hips (132 subjects; 162 post-THA and 88 native hips). Subjects were aged 59 ± 10years, with 66 males and 66 females. Comparison of IF-MRI and QF spaces between native and post-THA hips showed no differences (P > 0.12) and IF-RAD was higher in post-THA subjects (P = 0.01). No differences in the IF-MRI and QF spaces were present between native hips and different THA designs (P > 0.4). IF-RAD of metal-on-metal THA was higher than that of native hips (P = 0.01) and trended higher than ceramic-on-polyethylene THA (P = 0.08), with the remaining comparisons showing no significant differences (P > 0.4). Radiographic- and MRI-based measures in patients with standard THA do not show narrowing of IF and QF spaces.

The assessment of total hip arthroplasty

•. Technical aspects of total hip arthroplasty (THA), such as component position or the quality of the cement mantle, can be assessed post-operatively and may affect long-term outcome.•. The radiographic appearance of THA changes over time according to well-defined biomechanical and biological principles.•. There are fundamental differences between the design principles and subsequent behaviour of cemented and cementless components.•. Microscopic wear debris (particularly polyethylene debris) causes osteolysis and may lead to loosening, implant migration or fracture.•. Identification of important radiographic features may predict failure and allow timely and appropriate intervention.Soft tissue abnormalities related to THA can be assessed with ultrasound or MRI.Total hip arthroplasty (THA) is now a common surgical procedure. Radiologists are increasingly required to assess the prosthetic hip construct, either in the immediate post-operative period or later in the life of the patient, often years or decade...

Assessment of Total Hip Arthroplasty by Means of Computed Tomography 3D Models and Fracture Risk Evaluation

Total hip arthroplasty (THA) can be achieved by using a cemented or noncemented prosthesis. Besides patient's age, weight, and other clinical signs, the evaluation of the quality of the bones is a crucial parameter on which orthopedic surgeons base the choice between cemented and noncemented THA. Although bone density generally decreases with age and a cemented THA is preferred for older subjects, the bone quality of a particular patient should be quantitatively evaluated. This study proposes a new method to quantitatively measure bone density and fracture risk by using 3D models extracted by a preoperative computed tomography (CT) scan of the patient. Also, the anatomical structure and compactness of the quadriceps muscle is computed to provide a more complete view. A spatial reconstruction of the tissues is obtained by means of CT image processing, then a detailed 3D model of bone mineral density of the femur is provided by including quantitative CT density information (CT must be precalibrated). A finite element analysis will provide a map of the strains around the proximal femur socket when solicited by typical stresses caused by an implant. The risk for structural failure due to press-fitting and compressive stress during noncemented THA surgery was estimated by calculating a bone fracture risk index (ratio between actual compressive stress and estimated failure stress of the bone). A clinical trial was carried out including 36 volunteer patients (ages 22-77) who underwent unilateral THA surgery for the first time: 18 received a cemented implant and 18 received a noncemented implant. CT scans were acquired before surgery, immediately after, and after 12 months. Bone and quadriceps density results were higher in the healthy leg in about 80% of the cases. Bone and quadriceps density generally decrease with age but mineral density may vary significantly between patients. Preliminary results indicate the highest fracture risk at the calcar and the lowest at the intertrocanteric line, with some difference between patients. An analysis of the results suggest that this methodology can be a valid noninvasive decision support tool for THA planning; however, further analyses are needed to tune the technique and to allow clinical applications. Combination with gait analysis data is planned.

Vibroacoustography for the assessment of total hip arthroplasty

OBJECTIVES:This paper proposes imaging with 3-dimensional vibroacoustography for postoperatively assessing the uncovered cup area after total hip arthroplasty as a quantitative criterion to evaluate implant fixation.METHODS:A phantom with a bone-like structure covered by a tissue-mimicking material was used to simulate a total hip arthroplasty case. Vibroacoustography images of the uncovered cup region were generated using a two-element confocal ultrasound transducer and a hydrophone inside a water tank. Topological correction based on the geometry of the implant was performed to generate a 3-dimensional representation of the vibroacoustography image and to accurately evaluate the surface. The 3-dimensional area obtained by the vibroacoustography approach was compared to the area evaluated by a 3-dimensional motion capture system.RESULTS:The vibroacoustography technique provided high-resolution, high-contrast, and speckle-free images with less sensitivity to the beam incidence. Using a 3-dimensional-topology correction of the image, we accurately estimated the uncovered area of the implant with a relative error of 8.1% in comparison with the motion capture system measurements.CONCLUSION:Measurement of the cup coverage after total hip arthroplasty has not been well established; however, the covered surface area of the acetabular component is one of the most important prognostic factors. The preliminary results of this study show that vibroacoustography is a 3-dimensional approach that can be used to postoperatively evaluate total hip arthroplasty. The favorable results also provide an impetus for exploring vibroacoustography in other bone or implant surface imaging applications.

Radiographic assessment of primary hip arthroplasty

Assessment of total hip arthroplasty with plain radiography remains the first choice of investigation for postoperative review and investigation of any subsequent symptoms or problems. A working knowledge of the radiographic appearance of hip arthroplasty and how this appearance changes with time is important to identify potential or evolving problems. Most of our knowledge of these radiographic features comes from observations made from arthroplasty outcome studies rather than directed research and as such, is not readily available as a single resource. This article summarizes the features seen after primary total hip arthroplasty and how they may evolve, with a brief review of the underlying biological and biomechanical principles. The technical assessment of the postoperative radiograph is considered, together with important landmarks and subsequent long-term changes. We emphasize the importance of appreciating features that identify patients at risk for revision surgery and reinforce the concept that changes may vary depending on the type of implant used. With basic principles of radiology, biology and biomechanics, orthopaedic surgeons and radiologists can accurately assess the majority of radiographs taken after total hip arthroplasty.

Objective functional assessment of total hip arthroplasty following two common surgical approaches: The posterior and direct lateral approaches

Despite the high number of total hip arthroplasty (THA) procedures performed each year, there is no common consensus on the best surgical approach. Gait is known to improve following THA although it does not return to what is typically quantified as normal, and surgical approach is believed to be a contributing factor. The current study evaluates postoperative hip function and provides an objective assessment following two common surgical approaches: the McFarland-Osborne direct lateral and the southern posterior. Faced with the common problem of providing an objective comparison from the wealth of data collected using motion analysis techniques, the current study investigates the application of an objective classification tool to provide information on the effectiveness of each surgery and to differentiate between the characteristics of hip function following the two approaches. Seven inputs for the classifier were determined through statistical analysis of the biomechanical data. The posterior approach group exhibited greater characteristics of non-pathological gait and displayed a greater range of functional ability as compared with the lateral approach cohort. The classification tool has proved to be successful in characterizing non-pathological and THA function but was insufficient in distinguishing between the two surgical cohorts.

Visual analog scale for the assessment of total hip arthroplasty

The use of a visual analog scale (VAS) for the assessment of total hip prostheses was evaluated in 54 patients (58 hips), on average 3.4 years following operation. The Harris hip scores were determined in each case and the patients were also asked to record their overall assessment of their new hips on a VAS. Five patients (6 hips) were unable to understand and use the VAS. For the remaining 49 patients (52 hips), the Harris hip score averaged 84 (41–100) and the VAS score 75 (2–100). There was a high correlation between the Harris hip scores and the VAS scores (+0.84). Use of a VAS provides a simple and reliable basis for the assessment of a total hip arthroplasty.

Clinical and Roentgenographic Assessment of Total Hip Arthroplasty

A new total hip scoring system is presented and applied in a group of patients who were treated by revision of total hip arthroplasty. The Mayo hip score combines clinical (80 points) and roentgenographic (20 points) data in a 100-point score. The roentgenographic input into the score decreased the percentage of good-to-excellent results because of the high frequency of roentgenographic signs of loosening. With the Harris rating, there were 63% good-to-excellent results, 12% fair results, and 26% poor results a mean of 4.25 years after component revision of total hip arthroplasty. With the Mayo system, there were 52% good-to-excellent results, 19% fair results, and 29% poor results a mean of 4.25 years after revision. A modification of the roentgenographic rating system would apply the Mayo hip score to noncemented total hip arthroplasties.