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Anthony M DiGioia

Publications and source records attributed to Anthony M DiGioia.

9 recordsLinked to original sources
PubMed2006

Functional pelvic orientation measured from lateral standing and sitting radiographs.

We prospectively obtained preoperative and 3-month postoperative lateral pelvic radiographs in the standing and sitting positions from 84 patients who underwent total hip arthroplasty. We measured pelvic orientation (flexion extension) using the anterior pelvic plane as defined by the anterior superior iliac spines and pubic tubercles as references. There was a trend towards upright pelvic alignment when standing, with a mean anterior pelvic plane angle of 1.2 degrees (range, -22 degrees - +27 degrees). In the sitting position the pelvis tended to extend posteriorly, with a mean anterior pelvic plane angle of -36.2 degrees (range, -64 degrees - +4 degrees). There was a wide variation in the arc of pelvic flexion extension as patients moved from standing to sitting, with are of pelvic motion in some patients as mobile as 70 degrees and in others as stiff as 5 degrees. There was no significant variation between males and females or between preoperative and postoperative pelvic flexion extension. There were substantial variations in pelvic orientation when comparing standing and sitting for an individual patient and between different patients. This variation can be unpredictable, and may influence implant alignment and stability after total hip arthroplasty.

Adult↗
PubMed2006

Three-dimensional planning and virtual radiographs in revision total hip arthroplasty for instability.

Instability is one of the most challenging complications of total hip arthroplasty. The cause of instability is not always clear and treatment outcome is not always satisfactory. Treatment can be optimized by accurate identification of the cause of instability and precise surgical technique. In this case report, we illustrate the use of a three-dimensional (3-D) preoperative planner and virtual radiographic system to improve component position in revision total hip arthroplasty required because of recurrent dislocation. Using this technique, we identified common problems seen in patients with unstable hips after previous revision surgery including impingement, cup malpositioning, bone deficiency in the medial wall, and integrity of fixation screws. The computer-assisted system allowed preoperative planning with range of motion simulation and optimization of the acetabular cup position. The virtual radiographic system provided 3-D measurement of the cup position using a postoperative plane radiograph.

Aged↗
PubMed2004

A kinematic model for calculating cup alignment error during total hip arthroplasty.

Reduced range of motion, prosthetic impingement, and joint dislocation can all result from misalignment of the acetabular component (i.e. cup alignment) in patients undergoing total hip arthroplasty. Most methods for acetabular component alignment are designed to provide 45-50 degrees abduction and 15-25 degrees of operative anteversion (also known as flexion) with respect to the anterior pelvic plane coordinate system. Yet in most cases, this coordinate system is not assigned properly, due to differences in patient anatomy and improper positioning in the operating room. This misalignment can result in an error in the cup alignment, which can cause the above-mentioned consequences. This work presents a complete mathematical formulation for the analysis of the inaccuracies related to the anterior pelvic plane axes (APPA) definition and their effect on final cup orientation. We do this by introducing a method taken from Kinematics of Mechanisms, and by representing the errors in the APPA as three concurrent axes of rotation, followed by the version and abduction rotations which are defined relative to the previous rotations. We also present a sensitivity analysis of the results by introducing differential changes between sequential coordinate frames, which simulates the errors in the APPA and their effect on cup orientation. Finally, we demonstrate a computational method which provides corrected version and abduction angles to achieve the desired cup orientation, given that the actual measurement errors are known.

Arthroplasty, Replacement, Hip↗
PubMed2004

Computer-assisted orthopaedic surgery: minimally invasive hip and knee reconstruction.

Joint reconstructive surgery is experiencing new and important developments. Less and minimally invasive techniques for hip and knee replacement have been described recently by several investigators. They have outlined not only the positive aspects, but also some of the difficult challenges. Accuracy and safety of the surgery could be increased, despite the smaller approaches, with navigation tools. Although promising,the initial clinical experience is limited and needs to be supported by further, prospective analysis.

Arthroplasty, Replacement, Hip↗
PubMed2004

Less invasive total hip arthroplasty using navigational tools.

Although traditional total hip arthroplasty offers good visualization of bony landmarks and allows for the accurate orientation and fixation of implants, these benefits are achieved at the expense of extensive soft-tissue dissection and can result in postoperative complications and a delayed return to full function. To address these disadvantages, navigational tools were coupled with a mini-incision technique that allowed accurate bone preparation and orientation of the implant components without direct visualization of the bony landmarks. Additionally, image-guided systems provide three-dimensional information before and during surgery, making it possible to know, in real time, the orientation of implants and to visualize the full bony anatomy. This "computer-enhanced vision" allows surgeons to perform less invasive and eventually minimally invasive total hip arthroplasty with improved accuracy.

Arthroplasty, Replacement, Hip↗
PubMed2003

Mini-incision technique for total hip arthroplasty with navigation.

This prospective study compares a mini-incision technique and traditional posterior approach for total hip arthroplasty (THA). Thirty-three patients who had undergone a mini-incision THA were matched by diagnosis, gender, average age, and preoperative Harris Hip Score (HHS) to 33 patients who had undergone THA using the traditional posterior approach. The average length of the incision for group 1 was 11.7 cm (range, 7.3-13.0) and for group 2 was 20.2 cm (range, 14.8-26.0). At the 3-month follow-up, patients in the mini-incision group had significant improvement in limp (P<.05) and ability to climb stairs (P <.01) compared with the traditional group. At the 6 month follow-up, the mini-incision group was significantly better in terms of limp (P <.05), distance walked (P<.001), and stairs (P < 0.001). There was no significant difference between groups for pain, function, or range of motion at the 1-year follow-up examination.

Aged↗
PubMed2003

Ultrasound registration of the bone surface for surgical navigation.

OBJECTIVE: To allow non-invasive registration of the bone surface for computer-assisted surgery (CAS), this investigation reports the development and evaluation of intraoperative registration using 2D ultrasound (US) images. This approach employs automatic segmentation of the bone surface reflection from US images tagged with the 3D position to enable the application of CAS to minimally invasive procedures. METHODS: The US-based registration method was evaluated in comparison to point-based registration, which is the predominant method in current clinical use. The absolute accuracy of the US-based registration was determined using a phantom pelvis, with fiducial registration providing the ground truth. The relative accuracy was determined by an intraoperative study comparing the US registration to the point-based registration obtained as part of the HipNav experimental protocol. RESULTS: The phantom pelvis study demonstrated equivalent accuracy between point- and US-based registration under in vitro conditions. In the intraoperative study, the US-based registration was sufficiently consistent with the point-based registration to warrant larger-scale clinical trials of this non-invasive registration method. CONCLUSION: Ultrasound-based registration eliminates the need for physical contact with the bone surface as in point-based registration. As a result, non-invasive registration could fully unlock the potential of computer-assisted surgery, enabling development of the next generation of minimally invasive surgical procedures.

Humans↗