Preprints.org · Oct 21, 2026

Buffalo Hump, Neck Circumference, and Stroke Risk: A Narrative Review from a Surface Landmark to an Untested Intervention Target

By Huang X

Background: Buffalo hump is often oversimplified as localized fat accumulation, but its tissue composition is heterogeneous, and its clinical significance extends beyond cosmetic concerns. Neck circumference has accumulated relatively consistent evidence in cardiometabolic epidemiology, but most integrated analyses have used metabolic risk factors or metabolic syndrome as endpoints rather than hard endpoints such as stroke. Whether enlargement of the buffalo hump leads to an increase in neck circumference, and whether interventions that reduce the buffalo hump or neck circumference can translate into stroke prevention, remain unresolved. This narrative review examines the evidence linking buffalo hump and neck circumference to stroke risk and identifies structural gaps that currently preclude translation into prevention strategies. Methods: PubMed, Embase, the Cochrane Library, and the China National Knowledge Infrastructure were searched through March 2026 using terms for buffalo hump or dorsocervical fat, neck circumference, stroke or carotid atherosclerosis, and physical therapy or exercise. Population studies, intervention studies, mechanistic studies, and systematic reviews/meta-analyses reporting neck circumference, buffalo hump, carotid imaging, or stroke/cardiovascular endpoints were included. Case reports alone, narrative reviews without quantitative outcomes, and duplicate publications were excluded. After deduplication, title/abstract screening, and full-text assessment, 42 articles were included. As a narrative review, screening was performed by a single author without independent dual screening; selection bias cannot be excluded, and exhaustive retrieval according to systematic review standards is not claimed. Results: Buffalo hump is morphologically heterogeneous and frequently co-occurs with obesity and metabolic disorders. Increased neck circumference is associated with ischemic stroke and its subclinical precursor, independently of overall obesity. In a cohort of 3,009 patients with type 2 diabetes, high neck circumference was associated with an approximately 2.3-fold higher risk of a composite cardiovascular endpoint that included stroke; this estimate was not stroke-specific. The association was relatively robust in women in some East Asian cohorts; however, a cohort using the same cutoffs reported stronger predictive performance in men, and negative results from the Jackson Heart Study and the Framingham Offspring Cohort indicate that the direction and presence of the association are not uniform across populations. Pericarotid fat density and perivascular adipose tissue attenuation show incremental predictive signals beyond plaque burden in some studies, but this incremental value has not been consistently quantified, and their quantitative relationship with neck circumference has not been established. Surgical debulking, diet, physical therapy, and exercise have preliminary evidence, but none has reported postintervention neck circumference change in relation to stroke endpoints. Forward head posture remains an untested candidate pathway. Conclusions: The existing evidence supports treating buffalo hump and neck circumference as surface markers of stroke risk and potential intermediate targets, but it is still insufficient to support the clinical conclusion that treating or reducing buffalo hump, or lowering neck circumference, can prevent stroke. Concurrent collection of neck circumference, buffalo hump subtype, carotid imaging parameters, obstructive sleep apnea (OSA) severity, atrial fibrillation, forward head posture parameters, and stroke endpoints, together with systematic tracking of postintervention neck circumference trajectories, may translate the current descriptive associations into testable prevention hypotheses.

doi.org/10.20944/preprints202610.2030.v1Open accessPopulations