{
  "abstract": "Background\n\nEarly knee osteoarthritis (EKOA) may present with persistent symptoms despite mild radiographic changes. This prospective case-control study evaluated whether a pointwise encoding time reduction with radial acquisition (PETRA)-derived osteochondral thickness ratio (F ratio) could characterize structural differences between patients with EKOA and healthy controls.Methods\n\nParticipants underwent weight-bearing radiography, conventional magnetic resonance imaging (MRI), and 3.0 T PETRA MRI. The F ratio was calculated as the sum of mean superficial cartilage, deep cartilage, and osteochondral junction thicknesses divided by mean subchondral bone plate thickness. We compared F ratios and individual layer measures between 59 participants with EKOA and 54 healthy controls, assessed within-sample discrimination using receiver operating characteristic analysis with bootstrap internal validation, and evaluated inter-reader and intra-reader reproducibility in 23 participants.Results\n\nThe median F ratio was lower in the EKOA group than in healthy controls (1.998 (interquartile range, 1.604-2.567) versus 2.692 (2.401-3.000); P < 0.001). The adjusted geometric mean ratio was 0.776 (95% confidence interval, 0.703-0.857; P < 0.001). Among knees with measurable superficial cartilage, superficial cartilage thickness was lower in EKOA (0.944 ± 0.298 mm versus 1.331 ± 0.285 mm; P < 0.001), whereas subchondral bone plate thickness was greater (1.521 ± 0.468 mm versus 1.320 ± 0.270 mm; false-discovery-rate-adjusted q = 0.019). Superficial cartilage was non-identifiable in 16 of 59 EKOA knees (27.1%) and in no controls (P < 0.001). The apparent area under the curve for EKOA discrimination was 0.766 (bootstrap 95% confidence interval, 0.674-0.851); the optimism-corrected area under the curve was 0.765. Inter-reader and intra-reader intraclass correlation coefficients for the F ratio were 0.988 and 0.993, respectively.Conclusions\n\nThe PETRA MRI-derived F ratio was lower in EKOA and showed high measurement reproducibility with moderate within-sample discrimination. This measure may serve as a supplementary descriptor of osteochondral structural phenotype in patients with persistent knee pain and mild radiographic change. External and longitudinal validation is required before clinical diagnostic use.",
  "abstract_shown": true,
  "affiliations": [
    "Radiology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, CHN.",
    "Radiology, The First Affiliated Hospital of Dalian Medical University, Dalian, CHN.",
    "Translational Medicine, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, CHN.",
    "Ultrasound Medicine, Jinhua People's Hospital, Jinhua, CHN.",
    "Clinical Biospecimen, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, CHN.",
    "Radiology, Nanyang Central Hospital, Nanyang, CHN."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 10,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Hao Ma"
    },
    {
      "affs": [
        0
      ],
      "name": "Qianyi Zhao"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Jiaxin Yin"
    },
    {
      "affs": [
        2
      ],
      "name": "Yuhao Zhao"
    },
    {
      "affs": [
        3
      ],
      "name": "Jiawen Tang"
    },
    {
      "affs": [
        4
      ],
      "name": "Jiatuo Zhang"
    },
    {
      "affs": [
        0
      ],
      "name": "Shizhou Tang"
    },
    {
      "affs": [
        0
      ],
      "name": "Fengzhang Zhu"
    },
    {
      "affs": [
        5
      ],
      "name": "Zheng Yan"
    },
    {
      "affs": [
        0
      ],
      "name": "Xianglin Zhang"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/63yna5gg9fvfg.bib",
  "cited_by": 0,
  "doi": "10.7759/cureus.116678",
  "fulltext_url": "https://europepmc.org/articles/PMC13688584",
  "id": "63yna5gg9fvfg",
  "issns": [
    "2168-8184"
  ],
  "landing_url": "https://europepmc.org/article/MED/42923987",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2745|Osteoarthritis Treatment and Mechanisms"
    ]
  ],
  "openalex": "W7213912625",
  "pdf_url": "https://europepmc.org/articles/PMC13688584?pdf=render",
  "pmcid": "PMC13688584",
  "pmid": "42923987",
  "published": "2026-09-21",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/63yna5gg9fvfg.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:02Z",
      "native_id": "MED:42923987",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42923987"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2745|Osteoarthritis Treatment and Mechanisms",
      "subfield": "general"
    }
  ],
  "title": "Pointwise Encoding Time Reduction With Radial Acquisition MRI-Derived Osteochondral Thickness Ratio for Assessing Early Knee Osteoarthritis: A Prospective Case-Control Study.",
  "title_text": "Pointwise Encoding Time Reduction With Radial Acquisition MRI-Derived Osteochondral Thickness Ratio for Assessing Early Knee Osteoarthritis: A Prospective Case-Control Study.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:21:02Z",
  "url": "https://research.draconitic.com/paper/63yna5gg9fvfg",
  "venue": "Cureus",
  "versions": []
}