(129 days)
For Total Hip Replacement (THR) procedures
The Brainlab hip system 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 either on a patient's preoperative image data being processed by Brainlab IGS platforms, or 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 the skull, a long bone, or vertebra, can be identified relative to a CT, X-Ray, or MR-based model of the anatomy. The system aids the surgeon to accurately navigate a hip endoprosthesis to the preoperatively or intraoperatively planned position.
Example orthopedic surgical procedures include but are not limited to:
Total Joint Replacement
Minimally invasive orthopedic surgery
Tumor resection and bone/joint reconstruction
For Surface Replacement (SR) procedures
The Brainlab hip system is intended as an intraoperative image-guided localization system. It links a freehand probe, tracked by a passive marker sensor system to virtual computer image space on Brainlab IGS platforms. The image data is provided either in the form of preoperatively-acquired patient images or in the form of an individual 3D model of the patient's bone, which is generated by 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 appropriate and where a reference to a rigid anatomical structure, such as the skull, a long bone, or vertebra, can be identified relative to a CT, X-ray, or MR-based model of the anatomy. The system aids the surgeon in accurately navigating a hip endoprothesis to the preoperatively or intraoperatively planned position. Example orthopedic surgical procedures include but are not limited to: Partial/hemi-hip resurfacing
The Brainlab hip system is intended to enable operational planning and navigation in orthopedic hip replacement surgery. It links a surgical instrument, tracked by passive markers to virtual computer image space on an individual three-dimensional model of the patient's bone, which is generated through acquiring multiple landmarks either directly on the bone surface or by palpating bony landmarks through soft tissue and defining them directly on skin. The Brainlab hip system uses the registered landmarks to navigate the necessary surgical tools, e.g., cup reamer, cup inserter, stem broach handles and k-wires, to the planned position and orientation. Additionally, it enables to intra-operative measurement of implant position, including measurement of the changes in leg length and offset.
The Brainlab hip system provides a three-dimensional reconstruction of the relevant anatomical axes and planes of the femur and pelvis to aid the alignment of the implants and to determine leg length and offset parameters. Based on the selected procedure, the Brainlab hip system loads implant and instrument data that has been provided by the implant manufacturer. It is possible to individually choose the prostheses for each surgery, which are shown in the software in relation to the determined anatomical structures. If no implant data is available, to the user can enter
Here's a breakdown of the acceptance criteria and the study proving the device meets them, based on the provided text:
Acceptance Criteria and Device Performance Study for Brainlab Hip
The Brainlab Hip system is an intraoperative image-guided localization system for Total Hip Replacement (THR) and Surface Replacement (SR) procedures.
1. Table of Acceptance Criteria and Reported Device Performance
The provided document doesn't explicitly state "acceptance criteria" for the quantitative accuracy metrics in a tabular format. However, it presents the results of a clinical validation study and implicitly defines the desired performance by comparing it against a "gold standard" and a "safe zone."
Implicit Acceptance Criteria (Based on Study Results and "Safe Zone"):
| Metric | Acceptance Criteria (Implicit) | Reported Device Performance (Mean ± Standard Deviation) | Percentage of cases outside ±10° safe zone (Statistical) | Percentage of cases outside ±10° safe zone (Actual) |
|---|---|---|---|---|
| Lateral Registration | ||||
| Inclination | Minimal deviation from gold standard; >95% within ±10° safe zone | -1.1° ± 3.1° | 0.25% | 0% |
| Anteversion | Minimal deviation from gold standard; >95% within ±10° safe zone | 0.9° ± 4.3° | 2.32% | 0% |
| Supine Registration | ||||
| Inclination | Minimal deviation from gold standard; >95% within ±10° safe zone | 0.5° ± 2.2° | 0.0% | 0% |
| Anteversion | Minimal deviation from gold standard; >95% within ±10° safe zone | -0.9° ± 3.9° | 1.2% | 0% |
Interpretation: The implicit acceptance criterion appears to be that the deviation from the gold standard should be small, and crucially, that the percentage of cases falling outside a clinically recognized ±10° safe zone should be very low (ideally 0% in actual cases). The device met these criteria, reporting 0% of actual cases falling outside the safe zone for both registration methods.
2. Sample Size and Data Provenance for the Test Set
- Sample Size for Test Set: The clinical validation study included 50 total hip replacement surgeries. Two patients were excluded (one for data loss, one for pelvic reference array loosening), resulting in 48 cases for analysis.
- Data Provenance: The study was a prospective clinical validation study. The document does not specify the country of origin, but given the manufacturer is Brainlab AG based in Germany, it is highly probable the study was conducted in a European country, although this is not explicitly stated.
3. Number of Experts and Qualifications for Ground Truth
- The document does not explicitly state the number of experts used or their specific qualifications (e.g., radiologist with 10 years of experience) for establishing the ground truth.
- However, it does mention that the "gold standard" registration was determined by defining the APP points directly on bone from post-operative CT scans. This implies a process where medical professionals (likely surgeons or radiologists specialized in orthopedic imaging) would interpret these CT scans to establish the bone-based ground truth.
4. Adjudication Method for the Test Set
- The document does not describe an explicit adjudication method (e.g., 2+1, 3+1) for establishing the ground truth.
- The "gold standard" was determined by defining points directly on bone from post-operative CT scans. This suggests a direct measurement from imaging rather than a consensus process involving multiple human observers for classification, which is typical for image interpretation tasks.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No MRMC comparative effectiveness study was done to assess how much human readers improve with AI vs. without AI assistance.
- This study focused on the accuracy of the Brainlab Hip itself in determining cup orientation compared to a gold standard, rather than its impact on human reader performance.
6. Standalone (Algorithm Only Without Human-in-the-Loop) Performance
- A standalone performance study was done. The entire clinical validation study detailed in the document assesses the accuracy of the Brainlab Hip system (the device/algorithm) in measuring cup orientation.
- The system's measurements were compared directly to a "gold standard" derived from post-operative CT scans, indicating an evaluation of the device's inherent accuracy in a standalone capacity for the critical task of orientation measurement. The "virtually adapted cup orientation" based on Brainlab Hip's registration methods was compared to the CT-derived gold standard.
7. Type of Ground Truth Used
- The ground truth used was outcomes data / reference truth derived from post-operative CT scans combined with expert-defined anatomical landmarks.
- Specifically, the "gold standard registration" was established by defining the anterior pelvic plane (APP) points directly on bone from post-operative CT scans. This is a highly accurate, objective measurement based on direct anatomical information.
8. Sample Size for the Training Set
- The document does not specify the sample size used for the training set. The provided information pertains to the verification and validation of the device, focusing on a clinical validation study rather than the development or training of an underlying machine learning model (though the "Brainlab Hip has changed in the following from the predicate devices: ... Modified registration techniques have been integrated..." hints at potential algorithmic improvements).
9. How the Ground Truth for the Training Set Was Established
- Since the document does not specify a training set or its sample size, it does not describe how the ground truth for any training set was established.
§ 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).