Anatomy, Abdomen and Pelvis, Femoral Sheath


Article Author:
Navid Mahabadi
Valerie Lew


Article Editor:
Michael Kang


Editors In Chief:
Stephen Leslie
Karim Hamawy


Managing Editors:
Avais Raja
Orawan Chaigasame
Carrie Smith
Abdul Waheed
Khalid Alsayouri
Trevor Nezwek
Radia Jamil
Patrick Le
Anoosh Zafar Gondal
Saad Nazir
William Gossman
Hassam Zulfiqar
Steve Bhimji
John Shell
Matthew Varacallo
Heba Mahdy
Ahmad Malik
Sarosh Vaqar
Mark Pellegrini
James Hughes
Beata Beatty
Nazia Sadiq
Hajira Basit
Phillip Hynes
Tehmina Warsi


Updated:
7/16/2019 2:04:22 PM

Introduction

The femoral sheath is a structure within bilateral femoral triangles. The femoral sheath contains the femoral vein, artery, and lymphatics. The femoral nerve lies lateral to the femoral sheath and is not enclosed within the sheath.[1][2]

Anatomy

The femoral sheath attaches superiorly to the inguinal and lacunar ligaments and resides completely in the thigh. The femoral sheath is funnel-shaped, blending distally into the vessels adventitia. The upper end of the femoral sheath lies at the low inguinal level, where the lacunar ligament attaches to the pectineus muscle fascia 1 cm to 1.5 cm below Cooper’s ligament. Also at this low inguinal level lies the inguinal ligament and transversalis fascia (floor of the femoral canal). The inguinal ligament attaches to the upper end of the anterior wall of the femoral sheath.

The three walls of the femoral sheath include:

  • The posterior wall is formed by the iliaca fascia, along with a narrow ribbon of pectineus muscle fascia.
  • The anterior wall is formed by the transversalis fascia and partially the fascia lata.
  • The lacunar ligament forms the medial wall. The transversalis fascia moves laterally from the floor of the femoral canal toward the upper end of the venous compartment forming the medial wall.

Two additional coverings of the sheath include the fascia lata that descends from the inguinal ligament, in front of the femoral sheath, to cover and blend with transversalis fascia of the anterior wall. Scarpa’s fascia covers the femoral sheath superior to that.

The three compartments of the femoral sheath include:

  • The lateral compartment, which contains the femoral artery and femoral branch of genitofemoral nerve.
  • The middle compartment, which contains the femoral vein.
  • The medial compartment, where the femoral canal and lymphatics course through.

The femoral canal (the opening is called the femoral ring) is the most medial portion of the femoral sheath. The femoral canal connects the pelvic cavity to the anteromedial aspect of the thigh. The four borders of the femoral canal include the femoral vein laterally, lacunar ligament medially, inguinal ligament anteriorly, and pectineal ligament posteriorly. Fatty tissue and lymph nodes course through the canal.

Lateral to the femoral sheath is a muscular lacuna, bordered by the inguinal ligament, innominate bones anterior edge, and iliopectineal arch. The femoral nerve and iliopsoas muscle pass through this muscular lacuna.

Structure and Function

The femoral sheath allows for flexible compartments to ensure blood flow continues despite certain movements and increased demands. The femoral canal sits medial to the femoral vein, allowing the femoral vein to increase in size when there is increased venous return (such as in Valsalva). Additionally, the femoral sheath allows vessel mobility during hip flexion.[3]

Blood Supply and Lymphatics

The femoral vein is a thin-walled vessel with a lumen up to 1.5 cm diameter.

The femoral artery is a thick-walled vessel with a lumen less than half that of the vein. This artery lies lateral to the femoral vein.

The common iliac arteries (left and right) bifurcate off the aorta around the L4 level. The common iliac artery bifurcates into the internal and external iliac arteries. As the external iliac artery courses under the inguinal ligament, it becomes the common femoral artery, bifurcating into the superficial and deep femoral artery. Five percent of the time, the lateral femoral circumflex artery (LCFA) branches off the common femoral artery, while 95% of the time, the LCFA branches off the deep femoral artery. The medial circumflex femoral artery also branches off the common femoral artery, supplying the head of the femur. The profunda femoris artery has small vessels that supply the femur shaft.

The femoral canal contains the deep inguinal node of Cloquet, which drains fatty connective tissue, the clitoris, and penis.

Nerves

The femoral branch of the genitofemoral nerve courses through the lateral compartment of the femoral sheath and pierces the anterior surface of the sheath. This nerve innervates the skin of the anterior thigh, just above the femoral sheath.

The femoral nerve sits lateral to the femoral sheath and does not lie within the sheath.

Muscles

The iliacus, psoas major and pectineus muscles run posterior to the femoral sheath. The psoas major muscle runs posterior to the iliacus and pectineus muscle, thus, does not form the posterior wall of the femoral sheath.

Surgical Considerations

In cases of inguinal lymphadenectomy, it is important to preserve the muscular fascia, especially the femoral sheath components such as the fascia lata. This is to ensure the valves of the femoral vein and lymphatics can continue functioning by pumping blood and lymph drainage toward the heart. This can also prevent lymphadenopathy.[4]

Clinical Significance

Femoral hernias comprise 5% to 10% of groin hernias in adults. Elderly females are predisposed to femoral hernias because of the wider pelvis anatomy and loss of fatty tissue in the femoral canal with increasing age. The incidence of femoral hernias in pediatrics is 0.5%. Weakness at the fascial attachments of the upper end of the femoral sheath can allow protrusion of pre-peritoneal fat, omentum, small bowel or other visceral structures. These protrusions can break through the transversalis fascia floor of the femoral canal, emerging through a circular fascial opening and forming a femoral hernia. This opening may begin as only 1 cm in diameter, but expand if not treated properly. Smaller fascial openings may lead to increased risk of an incarcerated femoral hernia (intestines are stuck but still has blood flow) or even strangulation (intestines are stuck with the loss of blood flow). There are multiple locations a femoral hernia can present within the femoral sheath. The femoral type hernia is most common, occurring 98.5% of the time and is easiest to repair. The perivascular Velpeau’s hernia and Scrafeu’s hernia are rare and difficult to repair.[5]

The femoral vein is a relatively safe option for gaining central venous access when more proximal locations are less easily accessible. Ultrasound guidance helps reduce vascular bleeding by 60% when used for femoral vein cannulation. Routine use of ultrasound is not recommended for femoral vein cannulation as there are rare fatal complications as opposed to jugular or subclavian approaches. Also, the anatomical location of the femoral vein is fairly constant, allowing palpation of the femoral artery to be a fairly reliable technique. However, central venous catheter infection risks are increased with femoral vein catheters as opposed to subclavian approach.


  • Image 2100 Not availableImage 2100 Not available
    Contributed by Gray's Anatomy Plates
Attributed To: Contributed by Gray's Anatomy Plates

Interested in Participating?

We are looking for contributors to author, edit, and peer review our vast library of review articles and multiple choice questions. In as little as 2-3 hours you can make a significant contribution to your specialty. In return for a small amount of your time, you will receive free access to all content and you will be published as an author or editor in eBooks, apps, online CME/CE activities, and an online Learning Management System for students, teachers, and program directors that allows access to review materials in over 500 specialties.

Improve Content - Become an Author or Editor

This is an academic project designed to provide inexpensive peer-reviewed Apps, eBooks, and very soon an online CME/CE system to help students identify weaknesses and improve knowledge. We would like you to consider being an author or editor. Please click here to learn more. Thank you for you for your interest, the StatPearls Publishing Editorial Team.

Anatomy, Abdomen and Pelvis, Femoral Sheath - Questions

Take a quiz of the questions on this article.

Take Quiz
A patient presents to the emergency department complaining of chest tightness, sweating, and pain radiating down his left arm. Point of care troponin and ECG confirm an acute myocardial infarction. The patient is rushed to the cardiac catheterization lab where angioplasty is performed via the femoral artery. Which of the following nerves is located within the same fascial sheath as the femoral artery?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
A patient presents to the emergency department complaining of chest tightness, shortness of breath, and pain radiating down this left arm. Point of care blood test reveals elevated troponin and the patient is rushed for cardiac catheterization. The patient sneezes as the interventional cardiology is inserting his catheter at the femoral artery and the needle goes through the vessel and punctures the posterior wall of the femoral sheath. What structures form the posterior wall of the femoral sheath?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
While in the operating room a surgeon begins his cut over the proximal anterior thigh, just below the inguinal ligament, to gain access to the inguinal lymph nodes in the femoral sheath. In which compartment of the femoral sheath are the lymph nodes located?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
A 65-year-old male patient presents to the clinic complaining of back pain and numbness along his right anterior thigh. An abdominal CT scan reveals a mass on the patient's right psoas muscle that protrudes anteriorly into the adjacent tissue. Biopsy of the mass confirms malignant psoas sarcoma. Protrusion of the mass into which anatomical structures are most likely causing numbness in this patient's anterior thigh?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up

Anatomy, Abdomen and Pelvis, Femoral Sheath - References

References

Lytle WJ, Inguinal anatomy. Journal of anatomy. 1979 May     [PubMed]
Karakousis CP, The abdominoinguinal incision: the equivalent of thoracoabdominal incision for the lower quadrants of the abdomen. Journal of surgical oncology. 1998 Dec     [PubMed]
Kaki A,Blank N,Alraies MC,Kajy M,Grines CL,Hasan R,Htun WW,Glazier J,Mohamad T,Elder M,Schreiber T, Access and closure management of large bore femoral arterial access. Journal of interventional cardiology. 2018 Nov 19     [PubMed]
Khan Z,Nattanamai P,Keerthivaas P,Newey CR, An Evaluation of Complications in Femoral Arterial Sheaths Maintained Post-Neuroangiographic Procedures. Cureus. 2018 Feb 26     [PubMed]
Fitzgibbons RJ Jr,Forse RA, Clinical practice. Groin hernias in adults. The New England journal of medicine. 2015 Feb 19     [PubMed]

Disclaimer

The intent of StatPearls is to provide practice questions and explanations to assist you in identifying and resolving knowledge deficits. These questions and explanations are not intended to be a source of the knowledge base of all of medicine, nor is it intended to be a board or certification review of Surgery-Urologic. The authors or editors do not warrant the information is complete or accurate. The reader is encouraged to verify each answer and explanation in several references. All drug indications and dosages should be verified before administration.

StatPearls offers the most comprehensive database of free multiple-choice questions with explanations and short review chapters ever developed. This system helps physicians, medical students, dentists, nurses, pharmacists, and allied health professionals identify education deficits and learn new concepts. StatPearls is not a board or certification review system for Surgery-Urologic, it is a learning system that you can use to help improve your knowledge base of medicine for life-long learning. StatPearls will help you identify your weaknesses so that when you are ready to study for a board or certification exam in Surgery-Urologic, you will already be prepared.

Our content is updated continuously through a multi-step peer review process that will help you be prepared and review for a thorough knowledge of Surgery-Urologic. When it is time for the Surgery-Urologic board and certification exam, you will already be ready. Besides online study quizzes, we also publish our peer-reviewed content in eBooks and mobile Apps. We also offer inexpensive CME/CE, so our content can be used to attain education credits while you study Surgery-Urologic.