(90 days)
The TZ Medical skull pin is placed in a clamp and is applied to the patient's skull to hold their head and neck securely in a particular position when rigid fixation is desired. The clamp is indicated for use in open and percutaneous craniotomies as well as spinal surgery when rigid fixation is necessary.
The TZ Skull Pin is a sterile cervical traction skull pin manufactured from implant grade 316L stainless steel alloy. The TZ Skull Pin is used during neurosurgical procedures to immobilize the head in reference to the torso and to provide cervical immobilization.
Here's a breakdown of the acceptance criteria and study information for the TZ Skull Pin Adult device, based on the provided FDA 510(k) summary:
1. Table of Acceptance Criteria and Reported Device Performance
| Test | Acceptance Criteria (Implied/Direct) | Reported Device Performance |
|---|---|---|
| Skull Pin System Testing (using specified skull clamps) | The skull pins must perform safely and effectively in the specified skull clamps (V. Mueller Spetzler Skull Clamp-Model # M-1500; Integra Mayfield Skull Clamp-Model # A-1059; Integra Mayfield Skull Clamp-Model # A-2000) when subjected to the maximum force allowed by the skull clamp for a specified time period. No unacceptable deformation should occur. | Skull pins are safe to use in all 3 skull clamps. |
| Skull Pin Testing (Max Load Test) | The pins must hold the applied axial and radial loads for the required amount of time without slipping or material failure. | The pins held the load for the required amount of time without slipping or material failure. |
| Skull Pin Testing (Creep Test) | The pins must hold the applied axial and radial loads for the specified time frame without slipping or material failure. | The pins held the load for the required amount of time without slipping or material failure. |
| Cytotoxicity (ISO Elution method) | No evidence of causing cell lysis or toxicity. (Based on ISO 10993-5 (2009) standard). | Skull pin extract showed no evidence of causing cell lysis or toxicity. |
| Sensitization (ISO Guinea Pig maximization Sensitization Test) | No evidence of causing delayed dermal contact sensitization. (Based on ISO 10993-10 (2010) standard). | Skull pin extract showed no evidence of causing delayed dermal contact sensitization in the guinea pig. Skull pin was not considered a sensitizer in this test. |
| Irritation (ISO intracutaneous Study in Rabbits) | Meet the requirements of the test. (Based on ISO 10993-10 (2010) standard). | Test article met requirements of the test. |
| ISO Systemic Toxicity in Mice | No mortality or evidence of systemic toxicity. (Based on ISO 10993-11 (2006) standard). | No mortality or evidence of systemic toxicity from the skull pin extracts injected into mice. |
2. Sample Size Used for the Test Set and the Data Provenance
The document does not explicitly state the exact sample sizes (number of pins or animals) for each specific test in the "Summary of Performance Testing" section. It refers to testing being conducted but provides general results rather than specific numerical data for each test condition. The studies are laboratory-based and use animal models for biocompatibility tests (guinea pigs, rabbits, mice) and mechanical testing of the pins. Data provenance is implied to be from the manufacturer's internal testing as part of their 510(k) submission.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
This information is not applicable and not provided in the document. The tests performed are primarily mechanical and biological (biocompatibility) evaluations based on established international standards (ASTM and ISO), not human reader evaluations or clinical trials. The "ground truth" for these tests is defined by the specific parameters and outcomes outlined in the referenced standards (e.g., absence of cell lysis, holding a load without failure).
4. Adjudication Method for the Test Set
This information is not applicable. Adjudication methods like 2+1 or 3+1 are used for human reader studies to establish a consensus ground truth. The tests described are objective, laboratory-based evaluations against predetermined criteria.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
This information is not applicable. The TZ Skull Pin is a physical medical device (neurosurgical skull pin), not an AI algorithm or an imaging device to be read by human experts. Therefore, no MRMC study or AI-related comparative effectiveness study was performed or is relevant to this device's submission.
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was done
This information is not applicable. As explained above, this device is a physical skull pin, not an algorithm.
7. The Type of Ground Truth Used
The ground truth for the performance tests (Skull Pin System Testing, Max Load Test, Creep Test) is defined by the pass/fail criteria of established engineering standards, specifically ASTM F1831-97 (implicitly referenced for performance) and the general requirement that the device performs safely and effectively without material failure or slipping.
For the biocompatibility studies (Cytotoxicity, Sensitization, Irritation, Systemic Toxicity), the ground truth is defined by the objective criteria and endpoints specified in the relevant international ISO standards (ISO 10993-5, ISO 10993-10, ISO 10993-11), such as the absence of cell lysis, dermal contact sensitization, irritation, or systemic toxicity.
8. The Sample Size for the Training Set
This information is not applicable. There is no "training set" in the context of this physical medical device. Training sets are relevant for machine learning algorithms.
9. How the Ground Truth for the Training Set was Established
This information is not applicable, as there is no training set for this device.
§ 882.4460 Neurosurgical head holder (skull clamp).
(a)
Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures.(b)
Classification. Class II (performance standards).