A hierarchy of computationally derived surgical and patient influences on metal on metal press-fit acetabular cup failure

To ensure potential long-term stability and survivorship for metal-on-metal hip resurfacing prostheses, implant migration would need to be minimised to encourage bone in-growth. This study uses the finite element method to investigate the effects of the surgical press-fit procedure on the bearing and interfacial contact mechanics, and on the initial stability of a metal-on-metal (MOM) hip resurfacing prosthesis. The finite element models simulated the press-fit procedure using different amounts of interference between the cup-bone (1–2mm). The resurfacing prosthesis was implanted anatomically into a 3-D bone model. Resultant hip joint loads were applied to the model through muscle and subtrochanteric forces. Results showed that increasing the friction and the interference between the cup and bone resulted in significant reductions in the relative micromotion between the cup and bone. This would ensure the immediate post-operative stability of the acetabular cup and provide adequate conditions for potential long-term bone in-growth and implant stability. The contact mechanics at the bearing surfaces, which has a large effect on tribological performance, was found to be little affected by changes at the cup-bone interface. These findings are consistent with the general satisfactory short and medium-term clinical results of metal-on-metal hip resurfacing prostheses. This study suggests that interference, friction and a mechanically sound bone structure are important parameters to promote implant stability and support.

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Comparing the cup deformation following implantation of a novel ceramic-on-ceramic hip resurfacing bearing to a metal standard in a cadaveric model

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1177/0954411919845721 ◽

2019 ◽

Vol 233 (6) ◽

pp. 603-610

Author(s):

Adam James Farrier ◽

Lauren Moore ◽

Will Manning ◽

Carolina Avila ◽

Simon N Collins ◽

...

Keyword(s):

Femoral Head ◽

Hip Resurfacing ◽

Attractive Alternative ◽

Acetabular Cup ◽

Metal Implants ◽

Press Fit ◽

Metal On Metal ◽

Fresh Frozen ◽

Ceramic Implants ◽

Cadaveric Model

Hip resurfacing is an attractive alternative to total hip replacement preserving bone and reducing dislocation risk. Recent metal-on-metal designs have caused failure due to metal wear debris. Ceramic implants may mitigate this risk. Deformation of the acetabular cup can affect the lubrication, producing high friction torques between the femoral head and the cup that would increase wear and/or lead to cup loosening due to femoral head clamping. Our objective was to quantify the deformation of a novel monobloc ceramic hip resurfacing cup component compared to a metal standard, in a fresh frozen cadaveric model using a press-fit technique representative of standard surgical conditions. For this study eight acetabula were prepared from four fresh frozen cadavers. One surgeon with extensive experience in hip resurfacing surgery (J.H.) prepared the acetabulum by sequential reaming. The implants were then impacted into the acetabulum. Four ceramic and four metal implants were used of equal and varying size. Deformation was measured peri-implantation, and at 30 min, using an optical high-precision deformation sensor (GOM GmbH, Braunschweig, Germany). The maximum inscribed circle and the measurement of radial segment techniques were used. Deformation was greater in the metal implants (mean: 34–22mm) immediately after implantation. At 30 min after implantation, the deformation increased to 36mm in the metal and 26mm in the ceramic cup. Greater diameter changes were observed in larger cups. Metal and ceramic implants did not return to the initial diameter. We conclude the ceramic resurfacing acetabular implants undergo similar deformation to existing metal-on-metal implants. The deformation observed was significantly less in the ceramic component at 30 min on one measure. Less deformation may result in better surface conditions and wear characteristics. Deformation change did not resolve after 30 min for both implants.

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Press-fit acetabular cup fixation: Principles and testing

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1243/0954411991534780 ◽

1999 ◽

Vol 213 (1) ◽

pp. 33-39 ◽

Cited By ~ 38

Author(s):

W Macdonald ◽

L V Carlsson ◽

G J Charnley ◽

C M Jacobsson

Keyword(s):

Acetabular Cup ◽

Press Fit ◽

Fixation Principles

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Effect of cementless acetabular cup geometry on strain distribution and press-fit stability

The Journal of Arthroplasty ◽

10.1016/s0883-5403(97)90068-1 ◽

1997 ◽

Vol 12 (2) ◽

pp. 207-212 ◽

Cited By ~ 35

Author(s):

Michael D. Ries ◽

Mark Harbaugh ◽

Jeff Shea ◽

Richard Lambert

Keyword(s):

Strain Distribution ◽

Acetabular Cup ◽

Press Fit

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Compression of the Femoral Vessels by a Pseudotumor after Metal-on-Metal Total Hip Arthroplasty

Case Reports in Orthopedics ◽

10.1155/2017/2594902 ◽

2017 ◽

Vol 2017 ◽

pp. 1-5

Author(s):

Yasuaki Tamaki ◽

Tomohiro Goto ◽

Takahiko Tsutsui ◽

Tomoya Takasago ◽

Keizo Wada ◽

...

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Vascular Compression ◽

Acetabular Cup ◽

Primary Metal ◽

Total Hip ◽

Circulatory Disturbance ◽

Metal Head ◽

Metal On Metal ◽

Femoral Vessels

Here we present a case of pseudotumor following total hip arthroplasty (THA) that resulted in a circulatory disturbance caused by compression of the femoral vasculature. A 63-year-old man presented with pain, swelling, and redness of the left leg 5 years after primary metal-on-metal THA using the AML-Plus stem, Pinnacle® acetabular cup, and 36 mm diameter Ultamet™ metal head system (DePuy Orthopaedics, Warsaw, IN). Enhanced computed tomography and magnetic resonance imaging revealed a large cystic lesion extending from the left hip anteriorly to the intrapelvic region and compressing the left femoral vessels. Percutaneous puncture of the lesion yielded a dark red aspirate and the patient was diagnosed to have a pseudotumor causing compression of the femoral vessels. We performed revision surgery to replace the metal head and metal liner with a smaller ceramic head and polyethylene liner without removal of the stem. Corrosion of the head-neck junction was identified intraoperatively with no obvious wear on the bearing surfaces. The left leg swelling and redness improved immediately postoperatively. A large pseudotumor should be kept in mind as a cause of vascular compression with unilateral leg edema in a patient who has undergone metal-on-metal THA.

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Clinical evaluation of a novel press-fit acetabular cup using “Ein-Bild-Roentgen-Analysis” (EBRA): A positive short-term prognosis

Journal of Orthopaedics ◽

10.1016/j.jor.2020.03.059 ◽

2020 ◽

Vol 22 ◽

pp. 33-37

Author(s):

B.A. Ishaque ◽

J. Wieczorek ◽

C.A. Fonseca Ulloa ◽

J.B. Seeger ◽

G.A. Ahmed ◽

...

Keyword(s):

Clinical Evaluation ◽

Acetabular Cup ◽

Short Term ◽

Press Fit

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Effect of interposed tissue and contamination on the initial stability of a highly porous press‐fit acetabular cup

Journal of Orthopaedic Research® ◽

10.1002/jor.24253 ◽

2019 ◽

Vol 37 (5) ◽

pp. 1117-1122 ◽

Cited By ~ 4

Author(s):

Daniel H. Wiznia ◽

Garrett Joyal ◽

Gregg Schmidig ◽

Raga Rajaravivarma ◽

Raja Lokesh ◽

...

Keyword(s):

Acetabular Cup ◽

Press Fit ◽

Initial Stability ◽

Highly Porous

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Diametral Clearance Effect on Friction and Wear Characteristics of a Metal-on-Metal Total Hip Arthroplasty

ASME/STLE 2007 International Joint Tribology Conference, Parts A and B ◽

10.1115/ijtc2007-44484 ◽

2007 ◽

Author(s):

Ming Shen ◽

Birgit Grundmann ◽

Gernot Liebentritt

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Wear Test ◽

Frictional Torque ◽

Acetabular Cup ◽

Total Hip ◽

Hip Simulator ◽

Pendulum Test ◽

Metal On Metal ◽

Friction And Wear Characteristics

Tribological performance of a metal-on-metal total hip arthroplasty was evaluated as a function of the diametral clearance between the femoral head and acetabular cup. Frictional torque results, measured by a pendulum apparatus, suggested that a threshold clearance existed. Below the threshold clearance, frictional torque increased nearly linearly as the clearance decreased. Beyond the threshold, the clearance effect was minimal. The wear results, measured using a hip simulator, showed that a running-in wear was present in the first million cycles. The subsequent steady-state wear rate was very low in all tested clearances. The highest running-in wear was associated with the largest clearance. These results demonstrated the usefulness of combining a pendulum test and a simulator wear test to fully characterize the clearance effect.

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Double-Modular Hip Device Design Susceptible to Stress Corrosion Failure

ASME 2009 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2009-204734 ◽

2009 ◽

Author(s):

Sara A. Atwood ◽

Eli W. Patten ◽

Kevin J. Bozic ◽

Lisa A. Pruitt ◽

Michael D. Ries

Keyword(s):

Femoral Head ◽

Femoral Anteversion ◽

Metal Alloy ◽

Leg Length ◽

Acetabular Cup ◽

Corrosion Failure ◽

Total Hip ◽

Press Fit ◽

Free Mobility ◽

Hip Replacements

Total hip replacements restore pain-free mobility to approximately 200,000 patients in the U.S. each year [1]. A typical hip system comprises a metal alloy stem, a femoral head (ceramic or metal alloy), and a polyethylene acetabular cup fit into a metal alloy backing. A modular press-fit Morse taper is commonly used to attach the femoral head to the stem. There are also more recent designs that incorporate a second interface at the neck-stem junction (Figure 1). Increased modularity in total hip replacement design allows the surgeon to intraoperatively preserve patient anatomy such as leg length and femoral anteversion and better balance the surrounding soft tissue for optimal biomechanics. However, modularity also increases the number of mechanical junctions and interfaces in the device which may lead to complications such as corrosion, wear, and fracture.

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Good mid-term results with the trident peripheral self-locking cup: a clinical evaluation and migration measurement with EBRA

Archives of Orthopaedic and Trauma Surgery ◽

10.1007/s00402-020-03639-5 ◽

2020 ◽

Author(s):

Dietmar Dammerer ◽

Philipp Blum ◽

David Putzer ◽

Andreas Tscholl ◽

Michael C. Liebensteiner ◽

...

Keyword(s):

Trial Registration ◽

Inclusion Criteria ◽

Acetabular Cup ◽

Term Outcome ◽

Long Term Outcome ◽

Press Fit ◽

Medical Histories ◽

Migration Analysis ◽

Radiological Analysis

Abstract Introduction The most common cause of failure in total hip arthroplasty (THA) is aseptic loosening. Uncemented cup migration analysis by means of Einzel–Bild–Roentgen–Analyse (EBRA) has shown to be a good predictive indicator for early implant failure if the cup migrates more than 2 mm within 4 years after surgery. In this study, we performed a migration analysis of an uncemented peripheral self-locking (PSL) press-fit cup after 4 years follow-up. Materials and methods We retrospectively reviewed all patients who received a trident PSL press-fit cup at our department between 2004 and 2017. A total of 636 patients were identified. As inclusion criteria for radiological analysis, a minimum follow-up of 2 years was defined. We reviewed medical histories and performed radiological analysis using EBRA software. EBRA measurements and statistical investigations were performed by two independent investigators. Results A total of 149 cups in 146 patients (female 82; male 64) met our inclusion criteria. Mean age at surgery was 65 years (33–89). We found a significant improvement in the WOMAC score pre- to postoperative (p < 0.0001). EBRA migration analysis showed a mean total migration of 0.6 mm (0.0–8.2) over our follow-up period of 4 years. Of the investigated cups, 69.8% showed a migration rate smaller than 2 mm in the investigated follow-up. Conclusion The acetabular cup used in our study provides low migration at final follow-up. Therefore, a good long-term outcome can be expected for the PSL cup. Trial registration Trial registration number is 20181024-1875 and date of registration is 2018-10-24.

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