No abstract

No abstract

Evidence-based practice emphasizes the examination and application of evidence from clinical research into diagnosis, prognosis, and outcomes based on a formal set of rules 1 . One method of evaluating evidence is to assign levels of evidence 2 . In this evidence hierarchy, extrapolations from basic science research are classified as the lowest level of evidence. However, especially in situations where higher-level research evidence is insufficient, such extrapolation based on a thorough knowledge of relevant anatomy often still serves to guide clinical reasoning. This importance of anatomy remains recognized within physical therapy education in the United States, both as part of program entrance requirements 3 and as a part of the required basic sciences content in entry-level curricular content 4 . In those circumstances where clinical diagnosis is solely based on anatomical extrapolation, knowledge of anatomical deviations with a potential impact on interpretation of test results becomes even more important.The lumbar plexus originates from the ventral rami of the L1-L4 nerve roots and projects laterally and caudally from the intervertebral foramina, posterior to the psoas major muscle. A communicating branch from the T12, also known as the subcostal nerve, often joins the first lumbar nerve [5][6][7][8][9][10] . The L2-L4 ventral rami first bifurcate into an anterior and posterior primary division. The T12 and L1 nerves and the L2-L4 anterior primary divisions supply muscular branches to the psoas major and quadratus lumborum. Both primary divisions then enter the lumbar plexus and give rise to six peripheral nerves. Within this plexus, the L1 nerve splits into a cranial and caudal branch. The cranial branch bifurcates into the iliohypogastric and ilioinguinal nerves, the former also formed by the subcostal nerve in people where this nerve contributes to the lumbar plexus. The caudal branch of the L1 nerve unites with the anterior division of the L2 nerve to form the genitofemoral nerve. The anterior divisions of the L2-L4 roots form the obturator nerve. The lateral femoral cutaneous nerve arises from the posterior divisions of the L2 and L3 roots; the posterior divisions of L2, L3, and L4 join to create the femoral nerve (Figure 1). Table 1 presents a summary of the normal presentation of nerves of the lumbar plexus based upon a review of several authoritative anatomical texts commonly used in physical therapy education [5][6][7][8][9][10] . The purpose of this study was to describe the anatomical variations in the lumbar plexus from the origin at the ventral roots of (T12) L1-L4 to the exit from the pelvic cavity based on our descriptive anatomy study of human cadavers as compared to the above description of normal anatomy [5][6][7][8][9][10] . Comparing our findings to anatomical variation described elsewhere in the literature, we will also suggest possible clinical implications ABSTRACT: This study used dissection of 34 lumbar plexes to look at the prevalence of anatomical variations in the lumbar plexu...

No abstract

No abstract