Identifying the procedural gap and improved methods for maintaining accuracy during total hip arthroplasty

Factors Predicting Pressure Injury Incidence in Older Adults Following Elective Total Hip Arthroplasty: A Longitudinal Study

OBJECTIVE

To identify the factors associated with pressure injury (PI) development in older adult patients who underwent elective total hip arthroplasty (THA).

METHODS

A nonexperimental longitudinal prospective study was conducted with a sample of 40 patients undergoing elective THA. Patients were evaluated for PI at hospital admission, 24 hours postsurgery, at discharge, and 1 month after surgery.

RESULTS

The incidence of PIs (category 1 or category 2) in this study was 7.9% 24 hours after surgery and 24.3% at discharge. The most common PI location was the sacrum/coccyx or the ischial tuberosity. This study found significant relationships between PIs and female sex (odds ratio [OR], 8.75), body fat mass percentage (OR, 1.15), and the motor score from a Functional Independence Measure scale (OR, 0.89). Finally, the following variables were also associated with PIs (P < .1): skeletal muscle mass (OR, 0.82), lower limb with osteoarthritis weight (OR, 0.61), lower limb without osteoarthritis weight (OR, 0.62), and geriatric depression scale (OR, 1.12).

CONCLUSIONS

This work identifies those patients at higher risk of PI, enabling targeted prevention and treatment in the population of patients undergoing elective THA. The findings of this study are in line with extant literature and suggest that women with a higher percentage of body fat and less mobility had a higher risk of PI.

A Vertical Measurement System to Predict the Change in Leg Length in Total Hip Arthroplasty

The management of leg lengths in total hip arthroplasty continues to challenge orthopaedic surgeons. The aim of this study is to test the reliability of a measuring device used to measure the resected femoral head and how the resulting intra operatively calculated change in leg length compares to the radiographically measured change in leg length. Four orthopaedic surgeons measured 20 femoral heads and the intra class coefficients of the raters were between 0.955 and 0.990 with a mean difference less 1 mm, indicating the reliability of the device. The ‘actual’ radiographic leg length correction of 50 patients and the ‘predicted’ intra operatively calculated correction was analysed with a linear regression model and 47 measurements were within 2 mm and the remaining 3 within 4 mm.

Computer-assisted navigation as a diagnostic tool in revision total hip arthroplasty: A case report

Revision total hip arthroplasty is a costly procedure accounting for approximately 14% of all hip arthroplasties. Compounding the cost considerations is the potential for serious injury to the patient when removing existing components. Such injury can result in not only increased morbidity but also dramatically increased costs. The use of computer-assisted navigation in revision total hip arthroplasty, while relatively uncommon, offers surgeons the ability to measure component position and orientation intraoperatively, thus allowing them the opportunity to modify their surgical plan, with the potential for decreasing both costs and iatrogenic injury. Here, we report a case of revision total hip arthroplasty where the use of computer-assisted navigation as a diagnostic tool allowed for intraoperative alterations in surgical plan and resulted in improved post-operative outcomes.

Birmingham Hip Resurfacing Using a Novel Mini-navigation System: A Case Report

Introduction:

Inaccurate positioning of acetabular and femoral components during Birmingham Hip Resurfacing (BHR) can lead to increased wear, edge-loading, and failure of the prosthesis, a consequence of substantial concern for young and active patients seeking long- term, post-operative survival of the joint. In turn, sizing of the acetabular component during BHR is limited by the size of the native femoral neck, and reaming of the acetabulum should be minimized to optimize the bony architecture for potential subsequent arthroplasties. Computer-assisted navigation systems (CAS) can improve the accuracy of component selection and positioning during total hip arthroplasty (THA); however, evidence for the usefulness of CAS in BHR is lacking. The present report summarizes a case of BHR performed with navigation to assist with component positioning.

Case Report:

A 34-year-old male martial arts instructor presented with a constant and localized pain in the left hip and groin. Following the examination, the patient was diagnosed with left hip impingement and osteoarthritis. Due to his age and active lifestyle, the patient elected to undergo BHR rather than THA. The navigation tool was used to assist with acetabular reaming and to confirm final cup placement. Post- operatively, standard, anteroposterior pelvic radiographs showed a final cup position of 39.0° inclination and 24.7° anteversion, which was confirmed by the navigation tool. A pre-operative leg length differential of 3mm was measured from pre-operative radiographs; however, leg lengths were equalized following BHR.

Conclusion:

This report summarizes a case of BHR performed in a young, active patient with the assistance of a novel surgical navigation tool. The use of the navigation device allowed for more accurate acetabular preparation and component positioning, maximizing the bone-sparing characteristics of BHR.

Leg length correction in computer assisted primary total hip arthroplasty: A collective review of the literature

AIM

The aim of this study was to determine whether computer assisted surgery (CAS) can provide a more accurate, reproducible technique to achieve equal leg lengths in total hip arthroplasty (THA) and to compare the clinical outcome with conventional on table judgement of leg lengths in unilateral total hip replacement.

METHODS

A collective review of the literature was undertaken utilizing applicable databases. Research criteria were the following: (1) Developing and developed country studies, (2) level II, III, IV and V studies, (3) human subjects only, (4) period of study from 1996 to 2017 - English text only. The identified publications were assessed for their relevance and methodology and 20 articles were selected.

RESULTS

The overall evaluation of the results demonstrates that CAS provides a more accurate reproduction of limb length in THA compared to conventional freehand THA. Short to medium-term studies have demonstrated no benefit in clinical outcome scores. There is a high degree of correlation between measurements provided by CAS intraoperatively and radiographic measurements postoperatively.

CONCLUSION

CAS provides a more accurate, reproducible technique to achieve limb length equality in THA compared to conventional freehand THA, however more intensive long-term studies are required to establish the effect on implant longevity and revision surgery rates in the two groups.

A new mini-navigation tool allows accurate component placement during anterior total hip arthroplasty

Introduction

Computer-assisted navigation systems have been explored in total hip arthroplasty (THA) to improve component positioning. While these systems traditionally rely on anterior pelvic plane registration, variances in soft tissue thickness overlying anatomical landmarks can lead to registration error, and the supine coronal plane has instead been proposed. The purpose of this study was to evaluate the accuracy of a novel navigation tool, using registration of the anterior pelvic plane or supine coronal plane during simulated anterior THA.

Methods

Measurements regarding the acetabular component position, and changes in leg length and offset were recorded. Benchtop phantoms and target measurement values commonly seen in surgery were used for analysis. Measurements for anteversion and inclination, and changes in leg length and offset were recorded by the navigation tool and compared with the known target value of the simulation. Pearson's r assessed the relationship between the measurements of the device and the known target values.

Results

The device accurately measured cup position and leg length measurements to within 1° and 1 mm of the known target values, respectively. Across all simulations, there was a strong, positive relationship between values obtained by the device and the known target values (r=0.99).

Conclusion

The preliminary findings of this study suggest that the novel navigation tool tested is a potentially viable tool to improve the accuracy of component placement during THA using the anterior approach.

The Influence of Presurgical Factors on the Rehabilitation Outcome of Patients Following Hip Arthroplasty

PURPOSE

The aims of this study were to evaluate the relationship between sociodemographic information, anthropometric values, clinical and presurgery factors, and length of stay (LOS) in older adult patients undergoing total hip arthroplasty (THA) and to predict which factors can delay the start of the rehabilitation program and increase the corresponding LOS.

METHODS

A prospective cohort study was conducted in an orthopedic inpatient unit with 40 patients undergoing THA.

FINDINGS

The Morse Fall Scale scores and pain intensity scores delayed the commencement of the rehabilitation program. Gender and social support were important determinants of LOS and rehabilitation outcome following THA. The weight of the lower limb without osteoarthritis followed by pain intensity and overweight patients also influenced LOS.

CONCLUSIONS/CLINICAL RELEVANCE

Functional outcomes after THA are variable, and the rehabilitation process is an important factor to regain their normal level of physical functioning. This factor can have an impact in the discharge of patients, in resource allocation and in health care of older adult patients.

Quantification of Imaging Error in the Measurement of Cup Position: A Cadaveric Comparison of Radiographic and Computed Tomography Imaging

Postoperative radiographs remain the standard for assessment of component placement following total hip arthroplasty (THA), despite the known limitations of radiographs. Computed tomography (CT) scanning offers improved accuracy, but its costs and radiation exposure are prohibitive. The authors performed a cadaver study to compare the error associated with radiographs with that of CT scans following THA. The authors also compared imaging with a novel mini-navigation system. Three board-certified orthopedic surgeons each performed 4 THA procedures (6 cadavers, 12 hips) via the posterior approach using a mini-navigation tool to assist with component placement. Cup position from imaging was compared with corrected CT values for anteversion and inclination, created by correcting the initial scan to align the anterior pelvic plane coplanar with the CT table, thus representing cup position not distorted by imaging or positioning. Anteversion from standard CT scans was within 2.5° (standard deviation [SD], 1.5°) of reference values (P=.25); radiographs showed an average error of 7.8° (SD, 4.3°) vs reference values (all values absolute means) (P<.01). The mini-navigation system provided anteversion values within an average of 4.0° (SD, 4.0°) of reference anteversion (P<.01). Standard CT values for inclination were within 2.4° (SD, 2.0°) of reference values (P=.53), whereas radiographic inclination values were within 2.5° (SD, 2.3°) (P=.12). Mini-navigation values for inclination were within 3.9° (SD, 3.2°) of reference inclination (P=.26). This study demonstrated that cup position as measured by radiographs is significantly less accurate than CT scans and that the mini-navigation system provided anteversion measurements that were of comparable accuracy to CT scans. [Orthopedics. 2017; 40(6):e952-e958.].

Intellijoint HIP®: a 3D mini-optical navigation tool for improving intraoperative accuracy during total hip arthroplasty

Total hip arthroplasty is an increasingly common procedure used to address degenerative changes in the hip joint due to osteoarthritis. Although generally associated with good results, among the challenges associated with hip arthroplasty are accurate measurement of biomechanical parameters such as leg length, offset, and cup position, discrepancies of which can lead to significant long-term consequences such as pain, instability, neurological deficits, dislocation, and revision surgery, as well as patient dissatisfaction and, increasingly, litigation. Current methods of managing these parameters are limited, with manual methods such as outriggers or calipers being used to monitor leg length; however, these are susceptible to small intraoperative changes in patient position and are therefore inaccurate. Computer-assisted navigation, while offering improved accuracy, is expensive and cumbersome, in addition to adding significantly to procedural time. To address the technological gap in hip arthroplasty, a new intraoperative navigation tool (Intellijoint HIP^®) has been developed. This innovative, 3D mini-optical navigation tool provides real-time, intraoperative data on leg length, offset, and cup position and allows for improved accuracy and precision in component selection and alignment. Benchtop and simulated clinical use testing have demonstrated excellent accuracy, with the navigation tool able to measure leg length and offset to within <1 mm and cup position to within <1° in both anteversion and inclination. This study describes the indications, procedural technique, and early accuracy results of the Intellijoint HIP surgical tool, which offers an accurate and easy-to-use option for hip surgeons to manage leg length, offset, and cup position intraoperatively.