Histomorphometric Differences between Human and Sheep Femoral Cortices: Implications for Forensic Identification

Aims: This study compared histomorphometric and micromorphological features of the femoral cortex in humans and sheep (Ovis aries) for accurate forensic species identification, particularly in cases involving fragmented skeletal remains. Study Design: Comparative histomorphometric study. Place and Duration of Study: Department of Human Anatomy, University of Port Harcourt, Nigeria, with bone collection and analysis conducted between January and June 2024. Methodology: Thirty femoral midshaft samples were analyzed, consisting of 15 human and 15 sheep specimens. Samples were processed using the Modified Frost technique, sectioned, mounted, and examined under a Leica ICC 50K photomicroscope. Histomorphometric parameters including osteon count, osteon diameter, and Haversian canal dimensions were measured using ImageJ software. Independent t-tests (P = .05) were applied to assess species differences. Results: Significant differences were observed in secondary osteon count, osteon fragments, and Haversian canal dimensions (P < .001), with human femoral cortices showing higher remodeling activity and larger vascular channels. No significant difference was found in primary osteon count (p = 0.82). Micromorphologically, humans’ femoral cortices exhibited irregularly arranged secondary osteons, numerous osteon fragments, and well-developed Haversian and Volkmann’s canals. Sheep femoral cortices displayed a more organized plexiform pattern with fewer secondary osteons and smaller canals, indicating reduced remodeling activity. Conclusion: Key histomorphometric and micromorphological features reliably differentiate humans from sheep femoral bone. These findings support the applic​ation of histomorphometric and quali​ta​tive analys‍i​s as effective tools in forensic ant​hr‌opol​ogy f​or spe‍cies ide​ntifi​cation and contribute to the⁠ development​t of region sp​ecific⁠ forensic bone reference data.