Search Results

The MISHATM Knee System is indicated for patients with medial compartment knee osteoarthritis that have failed to find relief in surgical and/or non-surgical treatment modalities and are still experiencing pain that interferes with activities of daily living and are also unwilling to undergo or ineligible for total knee replacement due to age or absence of advanced osteoarthritis.

The MISHATM Knee System (Figure 1) is a prescription use, extra-capsular knee implant device that is comprised of a tibial base subassembly, femoral base subassembly, absorber subassembly, piston subassembly and locking screws. The tibial base subassembly, femoral base subassembly, piston subassembly and absorber subassembly are provided pre-assembled, and the implant is fixed with locking screws to the medial cortices of the distal femur and proximal tibia to share the loads with the knee joint. The articulating ball-and-sockets allow the implant to accommodate the natural motions of the knee. The implant bases and locking screws are made of titanium alloy and the sockets are CoCrMo alloy. The compressive component of the absorber is made of polycarbonate urethane. The femoral balls, tibial balls, and the internal lining of the absorber are made of carbon-fiber-reinforced polyetheretherketone (CFR-PEEK). The implant comes in two sizes (small and large) and right or left configurations.

The provided text describes the results of a clinical study for the MISHATM Knee System (formerly Calypso Knee System) and various non-clinical (bench) studies to demonstrate its safety and effectiveness.

Here's an analysis of the acceptance criteria and study data based on your request:

1. Table of Acceptance Criteria and Reported Device Performance:

• Clinically significant improvement ($ \ge $20% change AND $ \ge $10 points) from baseline on WOMAC pain questions in KOOS.
• Clinically significant improvement ($ \ge $20% change AND $ \ge $10 points) from baseline on WOMAC function questions in KOOS.
• Freedom from specified device-related serious adverse events (Deep infection requiring surgical intervention, Damage to adjacent neurovascular or ligament structures necessitating reconstruction, Non-union (HTO only)).
• Maintenance of implant integrity by radiographic assessment.
• (Additional explicit failure criterion: conversion to arthroplasty through 24 months).

Non-inferiority margin (δ) of -0.10. | Achieved.

• Success Rate (Multiple Imputation):
  • Calypso Knee group: 83.5%
  • Control (HTO) group: 57.2%
• Difference: Calypso Knee group led the Control (HTO) group by 26.3%.
• WOMAC Pain endpoint responder (Crude Observed, N=72): 95.8% (Calypso), 87.9% (HTO)
• WOMAC Function endpoint responder (Crude Observed, N=72): 91.7% (Calypso), 81.3% (HTO)
• No Safety Endpoint Event (CEC) (Crude Observed, N=81): 95.1% (Calypso), 93.8% (HTO)
• No Endpoint Implant Integrity Failure (Crude Observed, N=81): 98.8% (Calypso), 98.8% (HTO)
• No Endpoint Subsequent Surgical Intervention (Crude Observed, N=81): 98.8% (Calypso), 98.8% (HTO)

The study conclusion of non-inferiority was found to be robust through sensitivity analysis for missing data. |
| Non-clinical Performance Testing (Mechanical Function & Durability):

1. Absorber Unloading Capacity: Minimum compressive resistance force $ \ge $15 lbs at implanted length.
2. Durability, Wear, and Corrosion Resistance:
   • Mean polymeric wear rate $ \le $ 6.1 mm³ per one million cycles.
   • Mean metallic wear rate $ \le $ 0.004 mm³ per one million cycles.
   • Implant materials corrosion resistant.
   • Implant functionality maintained for $ \ge $ 10 million simulated gait cycles.
3. Static Strength: Will not fracture or break under static compressive load up to 60 lbs. | Bench Study Results:
4. Absorber Unloading Capacity: All specimens exceeded the performance criteria ($ \ge $ 15 lbs).
5. Durability, Wear, and Corrosion Resistance:
   • Mean polymeric wear rate: 0.248 mm³ per one million cycles (Met criterion $ \le $ 6.1).
   • Mean metallic wear rate: 0.004 mm³ per one million cycles (Met criterion $ \le $ 0.004).
   • No evidence of corrosion after immersion in simulated in vivo environment.
   • All test articles remained functional throughout testing (10.3 million cycles).
6. Static Strength: All articles survived a static compressive load of 65 lbs without permanent deformation or damage (Met criterion $ \le $ 60 lbs). |
   | Biocompatibility: Patient-contacting components demonstrated to be biocompatible. | Achieved. Testing per ISO 10993 series showed:

• Cytotoxicity: Non-cytotoxic
• Irritation: Non-irritant
• Sensitization: Non-sensitizing
• Implantation Effects: Null to minimal reactivity
• Material Mediated Pyrogenicity: Non-pyrogenic
• Systemic Toxicity, Genotoxicity, Carcinogenicity: Non-systemically toxic/genotoxic/carcinogenic (addressed via chemical characterization and toxicological risk assessment).
  A 26-week rabbit study showed no local or systemic toxicological effects. |
  | Sterility & Pyrogenicity: Performance data support sterility and pyrogenicity of sterile components. | Achieved.
• Sterility: Validated to SAL 10-6 using VDMax25 method (ANSI/AAMI/ISO 11137-1/-2).
• Pyrogenicity: All tested devices passed BET with $ \le $ 1 EU/device, meeting ANSI/AAMI ST72:2011. |
  | Shelf-life: Performance data support shelf life (sterility, package integrity, device functionality). | Achieved. Non-clinical performance testing confirmed a 5-year shelf-life. |
  | MR Compatibility: Safety and compatibility in MR environment. | MR Conditional:
• Displacement Force: Translation deflection angle of piral; maximum spatial gradient (D)(4) (bx).
• Torque: No torque.
• Image Artifacts: Maximum artifact size approx. 37 mm from implant with gradient echo pulse sequence (3.0 T MR scanner).
• RF Induced Heating: Maximum temperature rise $

Ask a specific question about this device

The WMT Modular Ulnar Head Implant is indicated for the following indications:

• Replacement of the distal ulnar head for disorders of the distal radioulnar joint in rheumatoid, degenerative and post-traumatic arthritis presenting with the following findings:
  • -pain and weakness of the wrist joint not improved by nonoperative treatment;
  • -instability of the ulnar head with radiographic evidence of dislocation or erosive changes of the distal radioulnar joint;
  • -failed ulnar head resection; e.g. Darrach resection
• Primary replacement after fracture of the ulnar head or neck.
• Revision following failed ulnar head arthroplasty.

The design features of the WMT Modular Ulnar Head Implant (Figure 1) is substantially equivalent to the Avanta uHead™ modular ulnar head implant (previously submitted and cleared under AVANTA ULNAR HEAD IMPLANT -- 510(k): K010786).

The WMT Modular Ulnar Head Implant was designed as a more anatomic alternative to the previously submitted and cleared Avanta uHead™ modular ulnar head implant (previously submitted and cleared under AVANTA ULNAR HEAD IMPLANT – 510(k): K010786) that utilizes axisymmetric head and stem components. The anatomy of the distal ulna is not axisymmetric, but rather consists of a head that is offset medial-lateral and dorsal-volar from the ulnar canal. Cadaveric analysis has shown that there is no correlation between head and stem location, thus a system where the head is offset relative to the stem is required to replicate normal anatomy and thus, joint kinematics.

The WMT Modular Ulnar Head is manufactured from cobalt chrome (ASTM F799 or F1537). The triangulated head will have a highly polished exterior surface across the articulating arc and distal surface, and will have a plasma sprayed textured surface laterally for tissue adhesion. The heads will be available in sizes ranging from 16mm to 22mm in diameter, 8mm to 11mm in height, and 1.5mm to 3mm in offset. The WMT Modular Ulnar Head Implant will contain suture holes for attaching soft tissues and a locking taper mechanism for engaging the modular head onto the stem.

The WMT Modular Ulnar Stem is manufactured from titanium (ASTM F136). The stems will be available in a standard and revision option: the standard stem will be tapered 4.5° to match the anatomical canal geometry while the revision stem will have a 1º taper to match proximal canal geometry. Each stem option will be available in distal diameters ranging from 5.5mm to 8mm and in two lengths: a standard length will have a 1mm platform and 25mm stem, and the extended length will have a 20mm platform and a 50mm stem. The stems will be fluted and will have a heavy grit blast finish over entire part except for the taper.

The provided text is a 510(k) summary for the WMT MODULAR ULNAR HEAD. It describes the device and its intended use, and claims substantial equivalence to a previously cleared device (Avanta uHead™ modular ulnar head implant). However, it does not contain any information about acceptance criteria, specific performance study results (statistical metrics, sample sizes, ground truth establishment, expert qualifications, adjudication methods), or MRMC studies.

The core of this submission is a claim of "substantial equivalence" based on design features, materials, and intended use, rather than a detailed performance study against explicit acceptance criteria.

Therefore, most of the requested information cannot be extracted from the provided text.

Here's what can be extracted:

1. Table of Acceptance Criteria and Reported Device Performance

Not explicitly stated. The document asserts "substantial equivalence" to a predicate device (Avanta uHead™ modular ulnar head implant) based on shared intended use, materials, and design features. It does not provide quantitative acceptance criteria or specific performance metrics obtained from a study comparing the WMT Modular Ulnar Head implant to these criteria.

2. Sample Size Used for the Test Set and Data Provenance

Not applicable. The document does not describe a clinical or performance study with a test set of data. The "testing results" mentioned generally refer to materials data and mechanical testing to support the safety, but not a study to evaluate performance against specific criteria.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

Not applicable. Ground truth establishment is irrelevant as no test set requiring such expert assessment is described.

4. Adjudication Method for the Test Set

Not applicable. No test set or expert adjudication process is described.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size of How Much Human Readers Improve with AI vs. Without AI Assistance

Not applicable. This device is a physical implant, not an AI-assisted diagnostic tool. Therefore, an MRMC study and AI-related metrics are irrelevant.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

Not applicable. This device is a physical implant, not an algorithm.

7. The Type of Ground Truth Used

Not applicable. As above, no test set with ground truth is discussed.

8. The Sample Size for the Training Set

Not applicable. No training set is mentioned as this is not a machine learning or AI-based device.

9. How the Ground Truth for the Training Set Was Established

Not applicable. No training set with ground truth is discussed.

Summary of what is present in the document:

The 510(k) submission for the WMT Modular Ulnar Head states its safety and effectiveness are supported by:

• Substantial equivalence information
• Materials data
• Testing results (implied mechanical/biocompatibility testing, not clinical performance against specific metrics)

The main argument for clearance is based on the device being "substantially equivalent" to the Avanta uHead™ modular ulnar head implant (K010786) in terms of intended use, materials, type of interface, and design features. The design differences (e.g., more anatomic shape, different sizing options) are presented as improvements, but without a comparative clinical performance study.

Ask a specific question about this device