Acetabular Shell Revision for Hip Arthritis

(RAS Trial)

Overseen By Marissa Puccio

Age: Any Age

Sex: Any

Trial Phase: Academic

Sponsor: Stryker Orthopaedics

Must not be taking: Steroids

Disqualifiers: High BMI, Infection, Neuromuscular disorder, Bone deterioration, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 2 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

Duration: Surgical procedure

56 Participants Needed

Trial Summary

What is the purpose of this trial?

This study will be a non-randomized, ambidirectional (retrospective and prospective) study where all subjects will be followed prospectively. The study will evaluate the survivorship of the RAS acetabular component in a previously failed total hip arthroplasty (THA) in a consecutive series of subjects who meet the eligibility criteria.

Do I have to stop taking my current medications for the trial?

The trial protocol does not specify if you need to stop taking your current medications. However, if you are receiving steroids in excess of normal physiological requirements, you may be excluded from the trial.

What data supports the idea that Acetabular Shell Revision for Hip Arthritis is an effective treatment?

The available research does not directly address the effectiveness of Acetabular Shell Revision for Hip Arthritis specifically. However, it does discuss various techniques for dealing with severe bone loss in hip surgeries, which is a related issue. For instance, one study mentions a new acetabular shell that helps maintain the natural position of the hip joint, which is important for good movement and stability. Another study talks about using a 'double-cup' method to handle severe bone defects, which could be similar to the challenges faced in hip arthritis cases. These studies suggest that innovative approaches in hip surgeries can lead to better outcomes, but they don't provide specific data on Acetabular Shell Revision for Hip Arthritis itself. ^{1 2 3 4 5}

What safety data exists for acetabular shell revision treatments like the Trident and Trident II systems?

Safety data for the Trident acetabular system indicates issues with incomplete seating of metal-backed ceramic liners, with a reported incidence of 16.4% in one study and 8% in another. Shell deformation may contribute to this problem. For the Trident II system, there have been reports of screw/shell interface failures, suggesting potential design flaws. These findings highlight technical challenges and the need for careful surgical technique to mitigate risks. ^{1 6 7 8 9}

Is the Restoration Anatomic Acetabular Shell a promising treatment for hip arthritis?

The Restoration Anatomic Acetabular Shell is a promising treatment for hip arthritis because it is designed to improve the fit and function of hip replacements, potentially leading to better movement and comfort for patients. ^{10 11 12 13 14}

Eligibility Criteria

This trial is for individuals needing a revision of a failed hip replacement component, specifically with the Restoration Anatomic Acetabular Shell. Participants must be adults who can follow post-op check-ups and have signed an informed consent form. Those with extreme obesity (BMI > 45), infections around the hip, immune suppression, mental or neuromuscular issues affecting recovery, poor bone quality, or sensitivity to device materials cannot join.

Inclusion Criteria

I am a man or a woman not currently pregnant.

I am a candidate for hip socket revision surgery.

Subject is willing and able to comply with postoperative scheduled clinical evaluations

Exclusion Criteria

I have a condition like Lupus or Paget's Disease affecting my bones.

Subject has a mental or neuromuscular disorder which would create an unacceptable risk of prosthesis instability, prosthesis fixation failure, or complications in postoperative care

I am on long-term steroids or have a weakened immune system.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive the Restoration Anatomic Acetabular Shell as part of the revision surgery for failed total hip arthroplasty

Surgical procedure

Follow-up

Participants are monitored for safety and effectiveness after treatment, including evaluation of adverse events and success rate

10 years

Treatment Details

Interventions

• Restoration Anatomic Acetabular Shell

Trial Overview The study is testing the long-term effectiveness ('survivorship') of the RAS acetabular shell in patients whose previous total hip arthroplasty has failed. It's a non-randomized study tracking patients both retrospectively and prospectively after they receive this specific implant.

Participant Groups

Group I: Restoration Anatomic Acetabular Shell Experimental Treatment 1 Intervention

Restoration Anatomic Acetabular Shell is already approved in United States, European Union for the following indications:

Approved in United States as Restoration Anatomic Shell for:

• Revision of previously failed total hip arthroplasty (THA)
• Primary and revision procedures for degenerative arthritis, rheumatoid arthritis, post-traumatic arthritis, or late stage avascular necrosis

Approved in European Union as Trident II Acetabular Shell for:

• Revision of previously failed total hip arthroplasty (THA)
• Primary and revision procedures for degenerative arthritis, rheumatoid arthritis, post-traumatic arthritis, or late stage avascular necrosis

Who Is Running the Clinical Trial?

Stryker Orthopaedics

Lead Sponsor

Trials

79

Recruited

20,500+

Kevin A. Lobo

Stryker Orthopaedics

Chief Executive Officer since 2012

Bachelor's degree in Commerce from McGill University, MBA from University of Toronto

Dr. Jorge Enrique Diaz

Stryker Orthopaedics

Chief Medical Officer since 2023

MD from University of Michigan Medical School

Findings from Research

In a study of 41 patients with massive acetabular bone loss, the use of an antiprotrusio cage combined with porous metal augments showed an 87.4% survival rate free from aseptic cage failure at 10 years, indicating good long-term efficacy of this reconstruction technique.

Patients experienced a significant reduction in their need for ambulatory aids after surgery, suggesting improved functional outcomes following the procedure.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Hip Arthroplasty With the Use of a Reconstruction Cage and Porous Metal Augment to Treat Massive Acetabular Bone Loss: A Midterm Follow-Up. Garceau, SP., Warschawski, Y., Joly, D., et al.[2022]

The novel double-cup construct using a Trabecular Metal Revision Shell for treating Paprosky type IIIA and IIIB acetabular defects showed no cases of acetabular loosening in a study of 20 patients over a mean follow-up of 2.4 years.

While the technique demonstrated significant improvements in hip function, with average Harris Hip Scores rising from 28.2 to 68.7, a 25% dislocation rate was noted, primarily occurring within the first year post-surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Double-Cup Construct: A Novel Treatment Strategy for the Management of Paprosky IIIA and IIIB Acetabular Defects. Webb, JE., McGill, RJ., Palumbo, BT., et al.[2018]

The new acetabular shell is designed to maintain the native hip center-of-rotation (COR) while providing effective fixation during revision total hip arthroplasty (THA), particularly in cases with significant acetabular bone loss.

This case series highlights the shell's potential to successfully lower the hip COR in challenging revision THA scenarios, suggesting it may improve surgical outcomes for patients with severe bone loss.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Difficult Revision Total Hip Arthroplasty Cases Treated with an Offset Head Center Acetabular Shell. Wassef, A., Sodhi, N., Khlopas, A., et al.[2019]

A customized cage was successfully used in 23 hips of 22 patients with severe acetabular bone loss during revision total hip arthroplasty, leading to significant improvement in hip function as measured by the Harris hip score, which increased from an average of 39.6 to 80.9 after surgery.

The method showed a good safety profile with no deep infections or severe complications, although two patients experienced dislocations that were managed effectively, indicating that while the technique is promising, further long-term studies are needed to assess its durability.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The use of customized cages in revision total hip arthroplasty for Paprosky type III acetabular bone defects. Mao, Y., Xu, C., Xu, J., et al.[2018]

In a study of 187 acetabular revisions where the old shell was retained, 25 cases required rerevision, highlighting the potential risks associated with this approach.

The rerevision rates varied significantly by shell design, with old spiked shells showing a 17% rerevision rate, suggesting that the design and condition of the existing shell should be carefully evaluated before deciding to retain it.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Survivorship of polyethylene liner exchanges performed for the treatment of wear and osteolysis among porous-coated cups. Hamilton, WG., Hopper, RH., Engh, CA., et al.[2022]

In a review of 117 hips from 113 patients who received the Trident acetabulum in total hip replacements, 16.4% showed incomplete seating of the metal-backed ceramic liner, indicating a potential issue with the implant's design or surgical technique.

The study suggests that the Trident shell may deform during implantation, which could hinder proper seating of the liner, highlighting the need for surgeons to be aware of this complication when using this prosthesis.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Incomplete seating of the liner with the Trident acetabular system: a cause for concern? Langdown, AJ., Pickard, RJ., Hobbs, CM., et al.[2016]

In a review of 68 patients who underwent total hip arthroplasties using the Trident acetabular system, 8% of the metal-backed ceramic liners were found to be incompletely seated, with a higher risk of 10% in primary surgeries compared to 0% in revision surgeries.

The study suggests that shell deformation may contribute to the malseating issue, and to mitigate this risk, the authors have adjusted their surgical technique by underreaming by 0.8 mm instead of 1.8 mm, especially in cases of sclerotic bone.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Seating of ceramic liners in the uncemented trident acetabular shell: is there really a problem? Howcroft, DW., Qureshi, A., Graham, NM.[2021]

This case series reports two instances of screw penetration through the Stryker Trident II acetabular shell, highlighting a potential design flaw in the implant system during total hip arthroplasty procedures.

Both cases were managed conservatively with weight-bearing as tolerated and radiographic monitoring, suggesting that while the failures occurred, they did not require more invasive interventions, but they do emphasize the need for careful intraoperative assessment of screw placement.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Failure of Screw/Shell Interface in the Trident II Acetabular System in Total Hip Arthroplasty. Ulrich, PA., Zondervan, RL., Cochran, JM.[2022]

Acetabular revisions using reinforcement rings and cages show good survival rates and functional outcomes, with a mean follow-up period of 8.8 years across 1327 procedures analyzed.

In cases of severe acetabular defects, the revisions still maintained a satisfactory mean Harris Hip Score of 76.3, indicating effective restoration of hip function despite challenges like aseptic and septic loosening.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Outcome of cages in revision arthroplasty of the acetabulum: a systematic review. Aprato, A., Olivero, M., Branca Vergano, L., et al.[2020]

The case report demonstrates that replacing a metal-ceramic crown with a CEREC 3-D crown can significantly improve aesthetic outcomes for patients, as seen in a 42-year-old patient who was dissatisfied with their previous crown.

The success of the CEREC crown replacement relies heavily on both the precision of the dentist's preparation and the quality of the laboratory work, leading to high satisfaction for both the patient and clinician.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Use of the CEREC system in dental practices. Esthetic reconstruction of the anterior teeth--a case report]. Di Rocco, D.[2016]

The use of a digital workflow combined with CAD/CAM technology in creating natural restorations allows for more predictable and aesthetically pleasing results compared to traditional methods.

In a case involving a 38-year-old patient with esthetic concerns, the interdisciplinary approach included periodontal surgery and CAD/CAM ceramic veneers, successfully restoring the natural appearance of the teeth.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

CAD-CAM natural restorations-Reproducing nature using a digital workflow. Segundo, ÂRTC., Saraiva, S., de Castro, C., et al.[2023]

The case study highlights the importance of interdisciplinary treatment planning and precise execution in the prosthetic rehabilitation of malpositioned anterior dental implants to achieve optimal esthetic results.

After using custom gold abutments and correcting a ridge defect, the study documented a stable and aesthetically pleasing outcome for maxillary central incisor implants over a 7-year period, demonstrating the long-term success of the approach.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Effect of Implant Abutment Design on Long-Term Soft Tissue Stability: A Clinical Case Report. Otero, N., Scarton, J., Pizzolante, LL., et al.[2019]

The study highlights the critical role of careful planning in reconstructive procedures for the front region of the jaw, especially in patients with class III relationships, which can complicate the process.

Five patients were treated using various techniques, including bone transplants and implants, emphasizing the need for both functional and aesthetic outcomes in successful reconstructions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Rehabilitation of the anterior portions of the maxilla and mandible by means of implants and bone grafts]. Neyt, L., Deryckere, F., Abeloos, J., et al.[2011]

A new procedure using a custom-made template and plastic foil allows for the accurate reproduction of internal contours of existing crowns, facilitating the rebuilding of composite core foundations for teeth that have undergone endodontic treatment.

This method addresses challenges faced when retrofitting existing crowns after core fractures or recurrent caries, improving the efficiency and effectiveness of dental restorations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Rebuilding core foundations for existing crowns using a custom-made template. Berksun, S.[2005]

References

1. United States pubmed.ncbi.nlm.nih.gov

Hip Arthroplasty With the Use of a Reconstruction Cage and Porous Metal Augment to Treat Massive Acetabular Bone Loss: A Midterm Follow-Up. [2022]

2. United States pubmed.ncbi.nlm.nih.gov

The Double-Cup Construct: A Novel Treatment Strategy for the Management of Paprosky IIIA and IIIB Acetabular Defects. [2018]

3. United States pubmed.ncbi.nlm.nih.gov

Difficult Revision Total Hip Arthroplasty Cases Treated with an Offset Head Center Acetabular Shell. [2019]

4. Germany pubmed.ncbi.nlm.nih.gov

The use of customized cages in revision total hip arthroplasty for Paprosky type III acetabular bone defects. [2018]

5. United States pubmed.ncbi.nlm.nih.gov

Survivorship of polyethylene liner exchanges performed for the treatment of wear and osteolysis among porous-coated cups. [2022]

6. England pubmed.ncbi.nlm.nih.gov

Incomplete seating of the liner with the Trident acetabular system: a cause for concern? [2016]

7. United States pubmed.ncbi.nlm.nih.gov

Seating of ceramic liners in the uncemented trident acetabular shell: is there really a problem? [2021]

8. United States pubmed.ncbi.nlm.nih.gov

Failure of Screw/Shell Interface in the Trident II Acetabular System in Total Hip Arthroplasty. [2022]

9. Italy pubmed.ncbi.nlm.nih.gov

Outcome of cages in revision arthroplasty of the acetabulum: a systematic review. [2020]

10. Switzerland pubmed.ncbi.nlm.nih.gov

[Use of the CEREC system in dental practices. Esthetic reconstruction of the anterior teeth--a case report]. [2016]

11. England pubmed.ncbi.nlm.nih.gov

CAD-CAM natural restorations-Reproducing nature using a digital workflow. [2023]

12. United States pubmed.ncbi.nlm.nih.gov

The Effect of Implant Abutment Design on Long-Term Soft Tissue Stability: A Clinical Case Report. [2019]

13. Belgium pubmed.ncbi.nlm.nih.gov

[Rehabilitation of the anterior portions of the maxilla and mandible by means of implants and bone grafts]. [2011]

14. United States pubmed.ncbi.nlm.nih.gov

Rebuilding core foundations for existing crowns using a custom-made template. [2005]