(288 days)
DASH hip is intended to be an intraoperative image-guided localization system to enable minimally invasive surgery. It links a freehand probe, tracked by a passive marker sensor system to virtual computer image space on an individual 3D-model of the patient's bone, which is generated through acquiring multiple landmarks on the bone surface.
The system is indicated for any medical condition in which the use of stereotactic surgery may be considered to be safe and effective, and where a reference to a rigid anatomical structure, such as a long bone, can be identified relative to the anatomy. The system aids the surgeon in controlling leg length and offset discrepancies.
Example orthopedic surgical procedures include but are not limited to:
Total Hip Replacement (THR) Revision surgery of THR Minimally Invasive THR Surgery
DASH hip is intended to enable operational navigation in minimally invasive orthopedic surgery. It links a surgical instrument, tracked by passive markers to virtual computer image space on an individual 3D-model of the patient's bone, which is generated through acquiring multiple landmarks.on the bone surface. DASH hip uses the registered landmarks to determine postoperative changes in leg length and offset,
DASH hip software intraoperatively registers the patient data needed for navigating the surgery. No preoperative CT-scanning is necessary.
Here's an analysis of the acceptance criteria and study information for the BrainLAB DASH hip, based on the provided text:
BrainLAB DASH hip: Acceptance Criteria and Study Details
1. Table of Acceptance Criteria and Reported Device Performance
The provided 510(k) summary does not explicitly list quantitative acceptance criteria in a table format. However, it states the overall performance goal and the conclusion of the pivotal study.
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Accuracy of navigation measurements for leg length and offset. | "The navigation accuracy of the leg length and offset measurements were evaluated in a prospective clinical study... it is shown that the accuracy relating purely to the navigation measurements for leg length and offset is comparable to the previously used leg length and offset technique from the predicate device... Thus, both techniques are considered to be equivalent." |
| Equivalence to predicate device (BrainLAB hip unlimited K083483). | "Dash hip has been verified and validated... The information provided... was found to be substantially equivalent with the predicate device BrainLAB hip unlimited (K083483) and Kolibri Image Guided Surgery System (K014256)." |
| Correct system functionality (registration, post-operative point acquisition, analysis). | "All tests have been successfully completed." (Referring to design verification activities) |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Test Set: 43 consecutive Total Hip Replacement (THR) surgeries.
- Data Provenance: The study was a "prospective clinical study," implying the data was collected specifically for this purpose in a real-world clinical setting. No specific country of origin is mentioned for the clinical study data.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The document does not provide details on the number of experts or their qualifications for establishing ground truth within the clinical study. It states that the study evaluated "navigation accuracy," implying a comparison to some established measurement standard, but doesn't specify who performed or validated these standards. Given the context of surgical navigation, it's highly probable that orthopedic surgeons were involved in the procedures and likely in assessing outcomes, but this is not explicitly stated as "ground truth establishment" by independent experts.
4. Adjudication Method for the Test Set
The document does not describe any specific adjudication method (e.g., 2+1, 3+1) for the clinical study data.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, an MRMC comparative effectiveness study involving human readers and AI assistance was not performed based on the provided text. The study compared the navigation accuracy of the DASH hip (which aids the surgeon) to a previously used predicate device's technique, not the improvement of human readers with AI vs. without AI assistance.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done
The document describes "verification of the software algorithm itself" as part of the design verification activities. This suggests a standalone evaluation of the algorithm's performance prior to integration with instrumentation and human interaction. However, detailed results of this standalone testing are not provided, only that it was "successfully verified." The primary clinical study focuses on the system's navigation accuracy, which inherently includes human interaction in using the system to measure.
7. The Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, etc.)
For the prospective clinical study, the ground truth for "leg length and offset measurements" would likely be derived from:
- Intraoperative measurements: Taken by the surgeon using conventional or established methods, possibly compared against pre-operative plans or fluoroscopic images.
- Radiographic measurements: Post-operative X-rays interpreted to determine actual leg length and offset changes.
The document states the study showed "the accuracy relating purely to the navigation measurements... is comparable to the previously used leg length and offset technique from the predicate device." This implies the "ground truth" was a reliable, established method of measuring these parameters, against which the DASH hip's measurements were compared.
8. The Sample Size for the Training Set
The document does not mention a specific "training set" or sample size for training. The DASH hip is a navigation system that uses landmarks acquired intraoperatively to generate a patient-specific 3D model. It does not appear to be a machine learning or AI system that requires a distinct "training set" in the conventional sense for image analysis or diagnostic tasks. Its core algorithm, though, would have been developed and refined using various data, potentially from predicate devices or simulated scenarios, but this is not described as a "training set."
9. How the Ground Truth for the Training Set Was Established
As noted above, a "training set" in the traditional machine learning sense is not explicitly described. The development and verification process included:
- Design verification: Covered instrument and system accuracy during registration, post-operative point acquisition, and analysis by comparing values to "externally-measured reference values." This implicitly establishes ground truth for verification tasks.
- Non-clinical validation: Performed with plastic bone models (sawbones) in "Usability Workshops (use labs)." Ground truth here would be the known anatomical dimensions of the models and the physical measurements taken.
- Pre-clinical validation: Performed in a "cadaver lab." Ground truth here would again be actual anatomical measurements and established surgical reference points.
These pre-clinical and verification steps provided data and a basis for establishing the correctness and accuracy of the device's measurements, which could be considered akin to establishing "ground truth" for development and early testing, distinct from a statistical "training set" for AI model development.
§ 882.4560 Stereotaxic instrument.
(a)
Identification. A stereotaxic instrument is a device consisting of a rigid frame with a calibrated guide mechanism for precisely positioning probes or other devices within a patient's brain, spinal cord, or other part of the nervous system.(b)
Classification. Class II (performance standards).