Does advancement in marker-less pose-estimation mean more quality research? A systematic review

Abstract

Recent breakthroughs in marker-less pose-estimation have driven a significant transformation in computer-vision approaches. Despite the emergence of state-of-the-art keypoint-detection algorithms, the extent to which these tools are employed and the nature of their application in scientific research has yet to be systematically documented. We systematically reviewed the literature to assess how pose-estimation techniques are currently applied in rodent (rat and mouse) models. Our analysis categorized each study by its primary focus: tool-development, method-focused, and study-focused studies. We mapped emerging trends alongside persistent gaps. We conducted a comprehensive search of Crossref, OpenAlex PubMed, and Scopus for articles published on rodent pose-estimation from 2016 through 2025, retrieving 16,412 entries. Utilizing an AI-assisted screening tool, we subsequently reviewed the top ∼1,000 titles and abstracts. 67 papers met our criteria: 30 tool-focused reports, 28 method-focused studies, and nine study-focused papers. Publication frequency trend has accelerated in recent years, with more than half of these studies published after 2021. Through a detailed review of the selected studies, we charted emerging trends and key patterns, from the emergence of new keypoint-detection methods to their integration into behavioral experiments and adoption in various disease contexts. Despite significant progress in marker-less pose-estimation technologies, their widespread application remains limited. Many laboratories still rely on traditional behavioral assays, under-using advanced tools. Establishing standardized protocols is the key step to bridge this gap, which will ultimately realize the full potential of marker-less pose-estimation and even greater insight into preclinical behavioral science.

Keywords: behavior classification; keypoint detection; marker-less pose estimation; rodent model; systematic review.

FIGURE 1

PRISMA flow chart (a) n = 16,412 studies were retrieved; out of which top n = 1,000 studies were screened using ASReview Tool. Full-text of Relevant records n = 69 were manually screened for the selection of the 30 Tool-focused (n = 4 Manual Inclusion), 28 Method-focused, and nine Study-focused included studies; *as the screening process is AI-assisted the quantitative details of excluded studies are unavailable. The ASReview screening result is represented as (b) the relevant studies found in chronological order and (c) rate of relevant record discovery.

FIGURE 2

(a) Based on the year of publication, the timeline of marker-less rodent pose-estimation based keypoint detection and behavior detection tools. (b) The current network represents the primary intended purpose and key capabilities. The main categories (Green node) include: Core Pose-estimation, Multi-Animal Tracking, 3D Pose-estimation, Real-Time Tracking, Behavior Classification, Behavior Prediction, and Infrastructure/Frameworks. The published tools (Blue node) are linked with their intended purpose.

FIGURE 3

(a) Chronological milestone for method-focused studies. (b) Marker-less pose-estimation tool usage frequency across method development and disease studies. (c) The cross-analysis map of disease conditions, behavioral assays, study-focused or method-focused studies, and tools to present the current scenario of marker-less pose-estimation technology in the disease studies.