ORPHA:2345
Isolated Klippel-Feil syndrome
Also known as: Congenital cervical vertebral fusion · Congenital fused cervical segments · Klippel-Feil malformation · Klippel-Feil sequence
Publications
57
34.1th percentile
Trials
0
Interventional, condition-specific
Researchers
327
Distinct authors in sample
Gene link
—
Readiness
1/6
Stages with a signal
Clinical definition (Orphanet)
Klippel-Feil Syndrome is characterised by improper segmentation of cervical segments resulting in congenitally fused cervical vertebrae.
How rare: 1-9 / 100 000 — about one to nine people per hundred thousand.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
Additional Mondo synonyms (3)
congenital cervical vertebral fusion · congenital fused cervical segments · nonsyndromic Klippel-Feil syndrome
Research stages
Trial readiness signals
Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”
1/6 stages with a signal
Research-stage checklist from open sources (GenCC, literature, Monarch when enriched, ClinicalTrials.gov). Not a prognosis or care recommendation.
- Gene identifiedNot found
No GenCC disease–gene assertion in this build
- LiteraturePresent
57 matched papers (17 in last 10 years) Source
- Phenotype characterisedNot found
No HPO disease–phenotype associations via Monarch for these Mondo IDs
- Animal modelNot found
No Alliance genotype “model of” associations via Monarch for these Mondo IDs
- Orphan designationNot found
No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source
- Interventional trialNot found
No matched interventional trial under our ClinicalTrials.gov rules
Biology
Genes and phenotypes
Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.
Do we know what causes it?
Not yet — the cause hasn't been pinned down in GenCC.
No strong gene–disease assertion joined for this Orphanet entity.
Phenotypes (Monarch / HPO)
None returned for this Mondo ID. That often means “not linked under this ID,” not “no clinical features.”
Animal models (Monarch / Alliance)
None returned for this Mondo ID. Empty here is not proof that no model organism work exists under another name or gene.
Monarch fetch 2026-07-29
Therapies
Designations, candidates, and chemicals
FDA OOPD and EMA orphan designations, Open Targets clinical candidates, and CTD chemical associations via MyDisease.info. These never change the interventional-trial headline.
Orphan designation (FDA · EMA)
No designation matched this disease via UMLS or preferred name on the FDA OOPD mirror or EMA orphan register. Absence here is not proof that none exists under another wording.
Open Targets candidates
No drugs or clinical candidates returned for this Mondo ID on Open Targets.
CTD chemicals (MyDisease.info)
No CTD chemical associations returned for this Mondo ID.
Literature
Is anyone studying this?
57
57 papers have ever been published on this condition (under this name). For scale, breast cancer has over 700,000. Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.
57 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 59 (publications denominator n=3967).
17 in the last 10 years · high confidence · 34.1th percentile (publications denominator)
Phrase hits: 57 · MeSH hits: 0
Who's working on it?
327
Distinct author names in 57 sampled papers — named people below.
Who's working on it?
No interventional trial matched this name; these authors publish on it in the sampled literature — a practical starting point for contact.
- 01Capri Y2 papers · 2020
Département de Génétique, Hôpital Robert Debré, Assistance Publique Hôpitaux de Paris, Paris 75019, France.
Papers in Europe PMC - 02Henderson FC Sr2 papers · 2019
Doctors Community Hospital, Georgetown University Hospital, United States.
Papers in Europe PMC - 03Liu Z2 papers · 2024
Department of Orthopaedic Surgery, Beijing Tian Tan Hospital, Capital Medical University, Beijing, China (mainland).
Papers in Europe PMC - 04Nishimura G2 papers · 2026
Department of Radiology, Musashino-Yowakai Hospital, Tokyo, Japan.
Papers in Europe PMC - 05Poca MA2 papers · 2024
Department of Neurosurgery, Vall d'Hebron University Hospital, Passeig Vall d'Hebron 119-129, 08035 Barcelona, Spain.
Papers in Europe PMC - 06Sahuquillo J2 papers · 2024
Department of Neurosurgery, Vall d'Hebron University Hospital, Passeig Vall d'Hebron 119-129, 08035 Barcelona, Spain.
Papers in Europe PMC - 07Abrahams AC1 paper · 2011
Department of Nephrology and Hypertension, University Medical Centre Utrecht, P.O. Box 85500, 3508 GA Utrecht, The Netherlands.
Papers in Europe PMC - 08Adcock J1 paper · 2019
Harvey Institute of Human Genetics, Greater Baltimore Medical Center, Baltimore, MD, USA.
Papers in Europe PMC - 09Adorno A1 paper · 2015
Department of Neurosurgery - AOOR Papardo-Piemonte, Contrada Papardo, 98158, Messina, Italy. aleadorno@yahoo.it.
Papers in Europe PMC - 10Alafaci C1 paper · 2015
Department of Neurosurgery - AOU Policlinico "G.Martino", Via Consolare Valeria, 98125, Messina, Italy. calafaci@unime.it.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
0
interventional trials for this specific condition
No interventional trial testing a treatment matched this specific condition name on ClinicalTrials.gov (observational studies and pan-disease registries are listed separately when present).
Data as of 11 September 2026 · last trial check 11 September 2026
No matched interventional trials. This is true for 77.2% of diseases in the trials denominator (5501 of 7126). Here are the researchers publishing on it.
high confidence · 38.6th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
No interventional trial testing a treatment was found for this specific condition name on ClinicalTrials.gov.
See who's working on it — people publishing on this disease are often the practical next contact when no trial is listed.
General rare disease registries you may be eligible for
These studies enroll across many rare conditions. They are not counted as evidence that anyone is studying this specific disease.
- NCT01793168·RECRUITING·Rare Disease Patient Registry & Natural History Study - Coordination of Rare Diseases at Sanford
Conditions: Rare Disorders · Undiagnosed Disorders · Disorders of Unknown Prevalence · Cornelia De Lange Syndrome
Other registries (secondary)
Broader net from EU CTIS, ISRCTN, and ICTRP when available — deduped against ClinicalTrials.gov IDs already counted above. Dual-model LLM relevance gates what we keep. These rows are not added to the interventional headline.
raw 2 · after dedupe 2 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 2 · dropped 0 · fetched 2026-07-29
Source notes: ictrp: Error: ICTRP public search unavailable (WHO portal is SPA-only; SOAP needs partnership). Tried: https://apps.who.int/tri
No secondary-registry studies passed dual-model relevance for this condition name (after dedupe).
Uncertain / not reviewed (2)
- isrctn·ISRCTN63972735·No longer recruiting·Prospective clinical study to evaluate the performance and safety of the TRYPTIK® Ti cage after cervical spinal fusion surgery
skipped — LLM skipped (--skip-llm)
- isrctn·ISRCTN89404187·No longer recruiting·Clinical outcome and fusion rates after surgery with TM Ardis interbody fusion system
skipped — LLM skipped (--skip-llm)
Where to find support
Condition-specific patient organisations, when Orphanet lists them, are on the disease’s Orphanet page. We also link umbrella groups that support undiagnosed and ultra-rare families.
Orphanet entry for Isolated Klippel-Feil syndrome — check Associations / patient organisations on that page.
India — NPRD
Last verified 2026-07-26This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.
Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.
How we counted this
Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.
"Isolated Klippel-Feil syndrome" OR "Congenital cervical vertebral fusion" OR "Congenital fused cervical segments" OR "Klippel-Feil malformation" OR "Klippel-Feil sequence" OR "nonsyndromic Klippel-Feil syndrome"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Isolated Klippel-Feil syndrome" OR "Congenital cervical vertebral fusion" OR "Congenital fused cervical segments" OR "Klippel-Feil malformation" OR "Klippel-Feil sequence" OR "nonsyndromic Klippel-Feil syndrome"
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: ok — strategies attempted: phrase; with hits: phrase
Run this search on ClinicalTrials.gov
Confidence reasoning
- Preferred label is multi-word and distinctive
- No synonyms dropped by stoplist
- No label/synonym collisions with other diseases in this corpus
Ingested 2026-07-26T19:55:21.128Z