The Ligament of Treitz, formally known as the suspensory muscle of the duodenum, is a thin, fibromuscular band of tissue. It connects a portion of the small intestine to the posterior abdominal wall. This ligament acts as an anchor for the gastrointestinal tract where the duodenum ends and the jejunum begins. It plays a significant part in maintaining the normal arrangement of the intestines.
Precise Anatomical Placement
The ligament is situated deep within the abdomen, originating high up near the posterior wall. Its uppermost connection involves fibers from the right crus of the diaphragm, the muscular structure separating the chest and abdominal cavities. From this origin, the ligament descends, blending with connective tissue surrounding the celiac artery and the superior mesenteric artery.
The structure extends downward to attach to the intestine at the duodenojejunal flexure. This flexure is the sharp bend marking the transition between the duodenum and the jejunum. The ligament defines the location where the digestive tract emerges from the fixed retroperitoneal space into the mobile, intraperitoneal space of the jejunum. This arrangement creates a distinct angle at the flexure, often situated to the left of the spine at the second lumbar vertebra. The ligament is composed of two parts: an upper section containing skeletal muscle fibers and a lower section made of smooth muscle.
Physiological Role of the Ligament
The primary function of this tissue band is to provide mechanical support and anchoring for the final segment of the duodenum. By tethering the duodenojejunal flexure to the posterior abdominal structures, the ligament prevents excessive movement or displacement. This fixation maintains the sharp angle of the flexure, which is necessary for efficient intestinal transit.
The smooth muscle fibers within the lower portion of the ligament are thought to contract, assisting in the digestive process. This contraction helps to widen the angle of the duodenojejunal flexure, facilitating the passage of chyme from the duodenum into the jejunum. Without this support, the intestine would be prone to kinking or prolapse, potentially leading to obstruction.
Clinical Importance in Diagnosis and Surgery
The Ligament of Treitz serves as a universally recognized anatomical landmark defining a major division within the digestive tract. This attachment point separates the upper gastrointestinal (GI) tract from the lower GI tract. Bleeding originating at or before the duodenojejunal flexure is classified as an upper GI bleed, while bleeding beyond this point is considered a lower GI bleed. This distinction is fundamental for diagnosis, as treatment methods differ significantly; upper GI bleeding is often treated using an endoscope, while lower GI bleeding requires different imaging or colonoscopy techniques.
The ligament’s location is also a point of reference for surgeons during various abdominal procedures. In pediatrics, the ligament is a specific marker used to identify intestinal malrotation. During embryonic development, the gut rotates, and the Ligament of Treitz should end up on the left side of the spine. If imaging studies show the ligament positioned to the right of the spine, it confirms a diagnosis of malrotation. This condition is a risk factor for a life-threatening intestinal twist called a volvulus, making the ligament’s precise location a vital diagnostic sign.