External Oblique Muscles, Lateral View

Description

Positioned in lateral profile, the male trunk is presented with the external oblique forming the superficial anterolateral abdominal wall, its serrated digitations arising from the external surfaces of ribs 5 through 12 and interdigitating superiorly with slips of serratus anterior. Muscle fibers run inferomedially toward a broad aponeurosis that approaches the linea alba anteriorly, while posterior fibers attach along the anterior half of the iliac crest and contribute to the posterior free margin near the lumbar region. The rib cage, thoracic vertebrae, and iliac crest provide firm bony landmarks behind the muscle. Clear landmarks. Clinically, the lateral view clarifies the muscular layering and fiber direction that guides both physical examination and operative planning: external oblique lies superficial to internal oblique and transversus abdominis, and its aponeurosis contributes to the anterior rectus sheath and the formation of the inguinal ligament from the anterior superior iliac spine to the pubic tubercle. That relationship matters in inguinal hernia repair, where the external oblique aponeurosis is opened to access the inguinal canal, and in sports-related side strain injuries where pain localizes along the lower costal attachments after trunk rotation. Fiber orientation also helps distinguish external oblique involvement from latissimus dorsi or intercostal sources of lateral thoracic pain. Ideal for gross anatomy and kinesiology teaching when you need to tie rib mechanics to abdominal wall function during rotation, forced expiration, and trunk flexion, and for surgical education materials covering the anterior abdominal wall and inguinal approaches. Publishers can also pair it with ultrasound or cross-sectional imaging to orient learners to surface anatomy and attachment sites along the ribs and iliac crest. Anatomical accuracy verified by SciePro's Medical Advisory Board.