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Posterior pedicle screw fixation: The Rogozinka Spinal Rod System Direct ("U"-shaped head) and Offset ("T"-shaped head) screws when placed in the vertebral levels L3 to S1 are intended only for patients: (a) having severe spondylolisthesis (Grades 3 and 4) of the fifth lumbar - first sacral (L5-S1) vertebral joint; (b) who are receiving fusions using autogenous bone graft only; and (c) who are having the device fixed or attached to the lumbar and sacral spine. Other and Offset Screws are intended only for sacral/iliac attachment as specified below.

Posterior hook and/or sacral/iliac screw fixation: The Rogozinski Rod System is intended for the treatment of degenerative disc disease (defined as spinal instability and one of the following: decreased disc height, ridging of vertebral end plates, scaring or thickening of ligamentous tissues and/or change in the facet process), scoliosis; spondylolisthesis; fracture; unsuccessful previous attempts at spinal fusion; or tumor resection. The Rogozinski Thoracolumbar Spinal Rod system is limited to non-cervical use.

The Rogozinski Thoracolumbar Spinal Rod System consists of two stainless steel rods attached to the spinal column through the use of hooks and/or screws. Universal cross-bars may be used to connect rods to provide a more rigid construct, as well as screws to rods and hooks to rods. Screws are provided in a variety of lengths and in up-angle, neutral, down-angle and pedicle hooks are provided in several sizes to accommodate varying patient morphology. Screws used with this system feature a "T" shaped head for offset attachment to the rod using a coupler, crossbar, and set screw or a "T"-shaped head for direct attachment to the rod use screw. Up-angle, down-angle, neutral and pedicle hooks may be attached either directly to the rod or offset from the rod attached with to the rod with a crossbar mechanism.

The provided text describes a spinal rod system and references several studies to support its safety and effectiveness. However, it does not include specific acceptance criteria for the device's performance, nor does it present a study proving the device meets such criteria directly.

Instead, the documents focus on demonstrating substantial equivalence to predicate devices and supporting the overall clinical utility and safety of pedicle screw fixation through meta-analyses, historical cohort studies, and randomized trials of similar systems or approaches, rather than directly evaluating the "Rogozinski Thoracolumbar Spinal Rod System Smith & Nephew Spine" against predefined performance metrics.

Therefore, I cannot provide a table of acceptance criteria and reported device performance as that information is not present. I can, however, extract details about the referenced studies that informed the device's acceptance.

Here's an analysis of the provided text based on your requested information, highlighting what is missing and what can be inferred:

1. Table of Acceptance Criteria and Reported Device Performance

• Acceptance Criteria: Not explicitly stated. The document does not define specific numerical thresholds (e.g., fusion rate > X%, complication rate < Y%) that the Rogozinski system needs to meet. Instead, acceptance appears to be based on demonstrating substantial equivalence to predicate devices and showing that the class of devices (pedicle screw fixation) is safe and effective through literature review and clinical studies.
• Reported Device Performance: Not directly reported for the Rogozinski system itself. The performance data presented refers to the general category of pedicle screw fixation or specific predicate devices in comparative studies.

Analysis of Supporting Studies Mentioned:

The three primary studies referenced are:

• Madjetko et al. (1994): A meta-analysis of literature on degenerative spondylolisthesis.
• Yuan et al. (1994): An open, non-randomized, historical cohort study comparing pedicle screw devices to non-instrumented and non-pedicle screw instrumentation.
• Zdeblick (1993): A prospective, randomized study of lumbar fusion comparing different instrumentation types.

Let's break down the information for these studies:

Study 1: Madjetko et al. (1994) - Degenerative Lumbar Spondylolisthesis: A Meta-Analysis of Literature 1970-1973

• 2. Sample size used for the test set and the data provenance:

  • Sample Size: This is a meta-analysis, not a single test set. It included 25 papers published between 1970 and 1973. The total number of patients across these papers is broken down by group:
    • Nonoperative/natural history: 3 papers total
    • Posterior decompression without fusion: 11 papers with 216 patients total
    • Posterior decompression without instrumentation: 6 papers with 84 patients total
    • Posterior decompression with "control" device (legally marketed Class II devices): 4 papers with 138 patients total
    • Posterior decompression with fusion with pedicular instrumentation: 5 papers (patient count not specified beyond 5 papers)
    • Anterior spinal fusion: 3 papers with 72 patients total.
  • Data Provenance: Retrospective (literature review, studies published between 1970-1973). Country of origin is not specified, but peer-reviewed medical literature.

• 3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

  • Not applicable. This is a meta-analysis. The "ground truth" would be established by the primary studies reviewed, which is not detailed here. The authors of the meta-analysis (Madjetko SM, Comolly P., Shott S) are the "experts" performing the analysis, but their qualifications are not provided beyond their names.

• 4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:

  • Not applicable. As a meta-analysis, it synthesizes existing literature; it does not involve a "test set" with adjudication in the typical sense of a device evaluation study.

• 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:

  • No. This is a meta-analysis of surgical outcomes, not a diagnostic imaging study involving human readers or AI.

• 6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:

  • No. Not applicable to this type of study.

• 7. The type of ground truth used (expert consensus, pathology, outcomes data, etc):

  • Outcomes data and clinical results from the original studies (e.g., fusion rates, patient satisfaction, maintenance of physiological spinal alignment).

• 8. The sample size for the training set:

  • Not applicable. This is a meta-analysis, not an algorithm development study.

• 9. How the ground truth for the training set was established:

  • Not applicable.

Study 2: Yuan et al. (1994) - Historical Cohort Study of Pedicle Screw Fixation in Thoracic, Lumbar, and Sacral Spinal Fusions

• This study is an "open, non-randomized, historical cohort study."

• 2. Sample size used for the test set and the data provenance:

  • Sample Size: 2,634 patients with degenerative spondylolisthesis.
    • Pedicle screw group: 2,177 (81.1%)
    • Non-instrumented group: 456 (17.0%)
    • Non-pedicle screw instrumentation group: 51 (1.9%)
  • Data Provenance: Retrospective ("historical cohort study"). Country of origin is not specified.

• 3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

  • Not specified. The study collected data on patients' outcomes, likely based on surgical records and follow-up examinations by various clinicians.

• 4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:

  • Not specified. Given the retrospective nature, it's unlikely a formal adjudication process was used in the context of ground truth establishment for a single test set. Data was "collected."

• 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:

  • No. This is a clinical outcomes study, not a diagnostic imaging study.

• 6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:

  • No. Not applicable.

• 7. The type of ground truth used (expert consensus, pathology, outcomes data, etc):

  • Outcomes data: Fusion rates, complication rates (intraoperative and postoperative events), implant breakage, screw fracture/loosening, re-operations, time to fusion, maintenance of spinal alignment.

• 8. The sample size for the training set:

  • Not applicable. This is a clinical study, not an algorithm development study.

• 9. How the ground truth for the training set was established:

  • Not applicable.

Study 3: Zdeblick (1993) - A Prospective, Randomized Study of Lumbar Fusion

• This is a "prospective, randomized study."

• 2. Sample size used for the test set and the data provenance:

  • Sample Size: 124 patients undergoing lumbar or lumbosacral fusion.
    • Group I (posterolateral fusion using autogenous bone graft): Number not explicitly stated but implied from totals.
    • Group II (autogenous posterolateral with Luque II screw-inter fixation system): Not explicitly stated.
    • Group III (autogenous posterolateral fusions supplemented with TSRH screw-rod fixation system): Not explicitly stated.
    • Specifically for degenerative or isthmic spondylolisthesis: 56 patients. 21 of these were in Group II.
  • Data Provenance: Prospective, randomized clinical trial. Country of origin not specified.

• 3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

  • Not specified. "Each patient clinically assessed and assigned a rating." This implies clinical experts (physicians) made these assessments, but their number or specific qualifications are not detailed.

• 4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:

  • Not specified. For clinical assessment, it's common for a single clinician to assess or for multiple to be involved in the overall care and outcome determination, but a formal adjudication method for ground truth labeling is not mentioned.

• 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:

  • No. This is a clinical trial comparing surgical techniques/devices, not a diagnostic imaging study.

• 6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:

  • No. Not applicable.

• 7. The type of ground truth used (expert consensus, pathology, outcomes data, etc):

  • Outcomes data primarily: Fusion rates (radiographic assessment), clinical results (ratings of "excellent," "good," etc.).

• 8. The sample size for the training set:

  • Not applicable. This is a clinical trial.

• 9. How the ground truth for the training set was established:

  • Not applicable.

Summary of Device-Specific Information from the Text:

The document primarily focuses on establishing substantial equivalence for the Rogozinski Thoracolumbar Spinal Rod System to numerous predicate devices. It then supports the utility of pedicle screw fixation (the general class of devices) through literature, rather than presenting a direct study validating the Rogozinski system's performance against specific acceptance criteria.

The "Information Bearing on Safety and Effectiveness" section aims to demonstrate that:

• Pedicular instrumentation, in general, improves fusion rates.
• Pedicle screw devices are at least as safe and effective as currently marketed Class II devices.
• While complication rates might be higher with instrumented fusion, pedicle screw devices do not have higher or more significant complications than other available Class II instrumentation.

This approach is typical for 510(k) submissions, where the focus is on showing the new device is "substantially equivalent" to legally marketed predicate devices, and the available scientific literature supports the safety and effectiveness of the device type.

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