From the Research
The fat anterior to the psoas muscle below the lower pole of the left kidney is indeed part of the kidney's lymphatic chain, containing para-aortic lymph nodes that receive lymphatic drainage from the kidney. This area is crucial in understanding the lymphatic drainage pattern of the kidney, which follows a predictable course with lymph vessels accompanying the renal vessels and draining into the lateral aortic (para-aortic) lymph nodes. For the left kidney specifically, lymphatic fluid drains into nodes located along the left renal vein, the para-aortic region, and into nodes anterior to the psoas muscle 1.
The provided studies, although focusing on different aspects of anatomy and imaging, support the understanding of the complex relationships between the kidney, psoas muscle, and surrounding structures. For instance, the study by 2 highlights the importance of considering anatomical variations, such as the interposition of the colon between the kidney and the psoas muscle, during percutaneous procedures to avoid complications. However, the most recent and highest quality study 1 provides detailed insights into the anatomy beneath the psoas muscle, introducing the concept of the cleft of psoas major (CPM), which contains neurovascular structures and loose connective tissue. This information is vital for surgical procedures like lateral lumbar interbody fusion, where identifying safe entry points is crucial.
Key points to consider include:
- The lymphatic drainage of the kidney and its relation to the psoas muscle and surrounding lymph nodes.
- The presence of the cleft of psoas major (CPM) and its contents, which can vary significantly between individuals.
- The importance of understanding these anatomical relationships for surgical planning and to minimize the risk of complications during procedures involving the kidney and lower back region.
Given the complexity of the anatomy and the potential for significant variation between individuals, it is essential to approach each case with careful consideration of the patient's specific anatomy, using high-quality imaging techniques to guide surgical planning and intervention 1.