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Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_16 | Pages 56 - 56
19 Aug 2024
McCalden RW Vasarhelyi EM Howard JL Lanting BA Naudie DD MacDonald SJ
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For over a decade, modular titanium fluted tapered (TFT) stems have demonstrated excellent clinical success for femoral revision total hip arthroplasty (THA) surgery. The aim of this study was to report the short-term outcomes of a novel modern monoblock TFT stem used for revision and complex primary THA with a minimum of 2 years follow-up.

We identified 126 patients who received a single monoblock TFT stem - 26 patients for complex THA (failed fracture fixation) and 100 patients for revision THA. The reasons for revision THA included 40 for previous prosthetic joint infection (PJI), 42 for aseptic loosening, 9 for trunnionosis, 9 for periprosthetic fractures. The Paprosky grading for femoral bone loss at the time of surgery and the measured subsidence of femoral stems at 3 months follow-up were determined. We evaluated the number and indications for re-operations.

The mean time from surgery was 3.9 years (range 2.0 to 6.9 years). A paired t-test analysis showed significant improvement from pre-operative versus post-operative clinical outcome scores (p<0.001) for HHS (38.76 +/- 15.24vs. 83.42 +/- 15.38), WOMAC (45.6 ± 19.0 vs. 69.9 ± 21.3) and SF-12 Physical component (31.7 ± 8.1 vs. 37.8 ± 11.3) and SF-12 Mental component (48.2 ± 12.2 vs. 51.6 ± 12.5). The Paprosky grading for femoral bone loss was Grade 1 (3.9%), Grade 2 (35.7%), Grade 3A (47.6%), Grade 3B (11.1%) and Grade 4 (1.6%) cases. There were 18 re-operations (14.7%) with 13 for PJI (7 treated with implant retention, 6 treated with a two-staged revision), 4 for instability and one for acetabular aseptic loosening. There were no aseptic failures of the stem.

This novel modern monoblock TFT stem provided reliable femoral fixation and has increasingly supplanted the use of modular TFT stems for complex primary and revision surgery in our institution.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_11 | Pages 57 - 57
1 Oct 2019
Broberg JS Teeter MG Lanting B Vasarhelyi EM Howard JL Yuan X Naudie DDR
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Introduction

Surgeons performing a total knee replacement (TKR) have two techniques to assist them achieve proper bone resections and ligament tension – gap balancing (GB) and measured resection (MR). GB relies on balancing ligaments prior to bony resections, whereas bony resections are made based on anatomical landmarks in MR. Many studies have been done to compare the implant migration and kinematics between the two techniques, but the results have been varied. However, these studies have not been done on modern anatomically designed prostheses using radiostereometric analysis (RSA). Anatomical designs attempt to mimic the normal knee joint structure to return more natural kinematics to the joint, with emphasis on eliminating both paradoxical anterior motion and reduced posterior femoral rollback. Given the major design differences between anatomical and non-anatomical prostheses, it is important to investigate whether one surgical technique may have advantages another. We hypothesize that there would be no difference between GB and MR techniques in implant migration, but that GB might provide better knee kinematics.

Methods

Patients were recruited to receive an anatomically designed prosthesis and randomized to groups where the GB or MR technique is used. For all patients in the study, RSA images were acquired at a 2 week baseline, as well as at 6 weeks, 3 months, and 6 months post-operatively. These images were used to collect the maximum total point motion (MTPM) of the tibial and femoral implant components relative to the bone using a model-based RSA software. A series of RSA images were also acquired at 3-months post-operatively at different knee flexion angles, ranging in 20° increments from 0° to 100°. Model-based RSA software was used to obtain the 3D positions and orientations of the femoral and tibial components, which were used to obtain the anterior-posterior (AP) contact locations for each condyle.


The Bone & Joint Journal
Vol. 101-B, Issue 5 | Pages 565 - 572
1 May 2019
Teeter MG Marsh JD Howard JL Yuan X Vasarhelyi EM McCalden RW Naudie DDR

Aims

The purpose of the present study was to compare patient-specific instrumentation (PSI) and conventional surgical instrumentation (CSI) for total knee arthroplasty (TKA) in terms of early implant migration, alignment, surgical resources, patient outcomes, and costs.

Patients and Methods

The study was a prospective, randomized controlled trial of 50 patients undergoing TKA. There were 25 patients in each of the PSI and CSI groups. There were 12 male patients in the PSI group and seven male patients in the CSI group. The patients had a mean age of 69.0 years (sd 8.4) in the PSI group and 69.4 years (sd 8.4) in the CSI group. All patients received the same TKA implant. Intraoperative surgical resources and any surgical waste generated were recorded. Patients underwent radiostereometric analysis (RSA) studies to measure femoral and tibial component migration over two years. Outcome measures were recorded pre- and postoperatively. Overall costs were calculated for each group.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_12 | Pages 52 - 52
1 Oct 2018
Naudie DD Broberg JS Howard JL Vasarhelyi EM Yuan X McCalden RW Teeter MG
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Introduction

The effectiveness of patient specific instrumentation (PSI) to perform total knee arthroplasty (TKA) remains controversial. Multiple studies have been published that reveal conflicting results on the effectiveness of PSI, but no study has analyzed the contact kinematics within knee joints replaced with the use of PSI. Since a departure from normal kinematics can lead to eccentric loading, premature wear, and component loosening, studying the kinematics in patients who have undergone TKA with PSI can provide valuable insight on the ability of PSI to improve functionality and increase longevity. The goal of the present study was to compare femoral and tibial component migration (predictive of long-term loosening and revision) and contact kinematics following TKA using conventional instruments (CI) and PSI based surgical techniques.

Methods

The study was designed as a prospective, randomized controlled trial of 50 patients, with 25 patients each in the PSI and CI groups, powered for radiostereometric analysis (RSA). Patients in the PSI group received an MRI and standing 3-foot x-rays to construct patient-specific cut-through surgical guides for the femur and tibia with a mechanical limb alignment. All patients received the same posterior-stabilized implant with marker beads inserted in the bone around the implants to enable RSA imaging. Patients underwent supine RSA exams at multiple time points (two and six weeks, three and six months, and one and two years). At 2 years post-op, a series of RSA radiographs were acquired at different knee flexion angles, ranging in 20° increments from 0° to 120°, to measure the tibiofemoral contact kinematics. Migrations of the femoral and tibial components were calculated using model-based RSA software. Kinematics were measured for each condyle for magnitude of excursion, contact location, and stability.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_13 | Pages 26 - 26
1 Oct 2018
McCalden RW Ponnusamy K Vasarhelyi EM Somerville LE Howard JL MacDonald SJ Naudie DD Marsh JD
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Introduction

The purpose of this study is to estimate the cost-effectiveness of performing total hip arthroplasty (THA) versus nonoperative management (NM) in non-obese (BMI 18.5–24.9), overweight (25–29.9), obese (30–34.9), severely-obese (35–39.9), morbidly-obese (40–49.9), and super-obese (50+) patients.

Methods

We constructed a state-transition Markov model to compare the cost-utility of THA and NM in the six above-mentioned BMI groups over a 15-year time period. Model parameters for transition probability (i.e. risk of revision, re-revision, death), utility, and costs (inflation adjusted to 2017 US dollars) were estimated from the literature. Direct medical costs of managing hip arthritis were accounted in the model. Indirect societal costs were not included. A 3% annual discount rate was used for costs and utilities. The primary outcome was the incremental cost-effectiveness ratio (ICER) of THA versus NM. One-way and Monte Carlo probabilistic sensitivity analysis of the model parameters were performed to determine the robustness of the model.


The Bone & Joint Journal
Vol. 97-B, Issue 12 | Pages 1640 - 1644
1 Dec 2015
Dzaja I Vasarhelyi EM Lanting BA Naudie DD Howard JL Somerville L McCalden RW MacDonald SJ

The purpose of this study was to compare clinical outcomes of total knee arthroplasty (TKA) after manipulation under anaesthesia (MUA) for post-operative stiffness with a matched cohort of TKA patients who did not requre MUA.

In total 72 patients (mean age 59.8 years, 42 to 83) who underwent MUA following TKA were identified from our prospective database and compared with a matched cohort of patients who had undergone TKA without subsequent MUA. Patients were evaluated for range of movement (ROM) and clinical outcome scores (Western Ontario and McMaster Universities Arthritis Index, Short-Form Health Survey, and Knee Society Clinical Rating System) at a mean follow-up of 36.4 months (12 to 120). MUA took place at a mean of nine weeks (5 to 18) after TKA. In patients who required MUA, mean flexion deformity improved from 10° (0° to 25°) to 4.4° (0° to 15°) (p < 0.001), and mean range of flexion improved from 79.8° (65° to 95°) to 116° (80° to 130°) (p < 0.001). There were no statistically significant differences in ROM or functional outcome scores at three months, one year, or two years between those who required MUA and those who did not. There were no complications associated with manipulation.

At most recent follow-up, patients requiring MUA achieved equivalent ROM and clinical outcome scores when compared with a matched control group. While other studies have focused on ROM after manipulation, the current study adds to current literature by supplementing this with functional outcome scores.

Cite this article: Bone Joint J 2015;97-B:1640–4.


The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 11_Supple_A | Pages 100 - 102
1 Nov 2012
Vasarhelyi EM MacDonald SJ

Obesity is an epidemic across both the developed and developing nations that is possibly the most important current public health factor affecting the morbidity and mortality of the global population. Obese patients have the potential to pose several challenges for arthroplasty surgeons from the standpoint of the influence obesity has on osteoarthritic symptoms, their peri-operative medical management, the increased intra-operative technical demands on the surgeon, the intra- and post-operative complications, the long term outcomes of total hip and knee arthroplasty. Also, there is no consensus on the role the arthroplasty surgeon should have in facilitating weight loss for these patients, nor whether obesity should affect the access to arthroplasty procedures.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 20 - 20
1 Sep 2012
Vasarhelyi EM Thomas B Grant H Deluzio KJ Rudan JF
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Purpose

Prospective randomized intervention trial to determine whether patients undergoing rotating platform total knee arthroplasty have better clinical outcomes at two years when compared to patients receiving fixed bearing total knee arthroplasty as measured by the WOMAC, SF-36 and Knee Society (KSS) scores.

Method

67 consecutive patients (33 males and 34 females; average age 66 years) were randomized into either receiving a DePuy Sigma rotating platform (RP) total knee arthroplasty (29 patients) or a DePuy Sigma fixed bearing (FB) total knee arthroplasty (38 patients). Inclusion criteria included patients between the ages of 45–75 undergoing single-sided total knee arthoplasty for clinically significant osteoarthritic degeneration.

Pain, disability and well-being were assessed using the WOMAC, KSS, and SF-36 preoperatively and at 6 months, 1 year and 2 years post-operatively. In addition, intraoperative measures were collected. Pre-operative radiographs were analyzed using the Kellgren and Lawrence Score, modified Scotts Scoring and mechanical axis. Post-operative radiographs were collected at 1 and 2 years and analyzed to identify evidence of prosthetic loosening, implant positioning and limb alignment.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 132 - 132
1 Sep 2012
Vasarhelyi EM Yach J
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Purpose

Anterior column screw fixation has been a useful tool in the management of acetabular fractures, either alone or in combination with other fixation techniques. Percutaneous insertion may be advantageous by limiting surgical dissection but little has been reported on its safety. The purpose of this study is to report on the efficacy and safety of percutaneous anterior column stabilization.

Method

In a consecutive series of 122 operatively treated acetabular fractures, 56 patients were treated with antegrade percutaneous anterior column stabilization either alone or in combination with other fixation techniques by a single surgeon (JY). The technique was selected when the anterior column portion of the fracture was undisplaced or could be reduced via indirect methods. Intraoperative fluoroscopy was used to guide the placement of either a 6.5 mm or 7.3 mm cannulated antegrade anterior column lag screw. Postoperative radiographs (anteroposterior and Judet views) were obtained in the recovery room, prior to discharge and at clinic follow up.