Inconsistencies in surface anatomy: The need for an evidence-based reappraisal

Accurate surface anatomy is a key component of safe clinical practice. But how consistent are modern clinical and surface anatomy texts in their reporting of common surface anatomy landmarks? Thirteen popular texts in common use were analyzed in detail: one clinical and anatomical reference text; seven clinical anatomy texts; two surface anatomy texts; and three clinical examination texts. Content relating to surface anatomy was reviewed, summarized, and assessed for consistency. Four main findings emerged: (i) there are numerous inconsistencies in clinically important surface markings (e.g., the femoral artery in the groin, superficial and deep inguinal rings, and accessory nerve in the posterior triangle), including inconsistencies within some texts; (ii) there is a consensus on many surface markings, e.g., the spleen and termination of the spinal cord; (iii) few texts address variation in surface anatomy related to age, sex, body mass, posture, respiration, and ethnicity; and (iv) the three standard clinical examination texts included in this review contain comparatively little surface anatomy. Seven surface anatomy landmarks were redefined within an evidence-based framework: termination of the spinal cord, supracristal plane, base of the appendix, renal length, the deep inguinal ring, the femoral artery in the groin, and the accessory nerve in the posterior triangle of the neck. An evidence-based framework is essential if surface anatomy is to be accurate and clinically relevant.