Topic: Lower Limb; Subtopic: Obturator Nerve and Hip Joint Movements
Keyword Definitions:
• Obturator Nerve: A nerve arising from the lumbar plexus (L2–L4) that supplies the medial thigh muscles responsible for adduction of the hip joint.
• Hip Joint Adduction: Movement of the thigh toward the midline, primarily performed by adductor muscles.
• Femoral Nerve: A major nerve of the anterior thigh supplying extensor muscles of the knee and sensation to the anterior thigh.
• Saphenous Nerve: A sensory branch of the femoral nerve that supplies the medial leg and foot.
• Sciatic Nerve: The largest nerve in the body, supplying the posterior thigh, leg, and foot.
Lead Question – 2015
A patient presents with defective adduction of the hip joint and pains in the hip and knee joint. Which nerve is involved?
a) Obturator nerve
b) Femoral nerve
c) Saphenous nerve
d) Sciatic nerve
Explanation: The obturator nerve (L2–L4) supplies the adductor muscles of the medial thigh. Injury to this nerve results in loss of hip adduction and referred pain to the medial thigh and knee, due to its articular branches. This may occur during pelvic surgery or childbirth trauma. Answer: (a) Obturator nerve.
1. The obturator nerve emerges from which part of the lumbar plexus?
a) L1–L2
b) L2–L4
c) L4–S1
d) L5–S2
Explanation: The obturator nerve originates from the anterior divisions of L2–L4 roots of the lumbar plexus. It descends through the pelvis, exiting via the obturator foramen to supply adductor muscles. Answer: (b) L2–L4.
2. Which muscle is supplied by the posterior division of the obturator nerve?
a) Adductor longus
b) Adductor brevis
c) Adductor magnus (adductor part)
d) Gracilis
Explanation: The posterior division of the obturator nerve supplies the adductor magnus (adductor part) and obturator externus muscles. The anterior division supplies adductor longus, adductor brevis, and gracilis. Answer: (c) Adductor magnus (adductor part).
3. In case of obturator nerve injury, which movement is primarily affected?
a) Flexion of the knee
b) Adduction of the thigh
c) Abduction of the thigh
d) Extension of the hip
Explanation: The obturator nerve controls adductor muscles. Damage to it causes weakness in adduction of the thigh, making crossing legs difficult. Sensory loss may occur on the medial thigh. Answer: (b) Adduction of the thigh.
4. The sensory branch of the obturator nerve supplies:
a) Lateral thigh
b) Medial thigh
c) Posterior thigh
d) Anterior leg
Explanation: The obturator nerve provides sensory innervation to the medial aspect of the thigh and articular branches to the hip and knee joints. Damage causes pain in these regions. Answer: (b) Medial thigh.
5. A pelvic tumor compressing the obturator nerve will cause weakness in:
a) Knee flexion
b) Thigh abduction
c) Thigh adduction
d) Knee extension
Explanation: Compression of the obturator nerve affects adductor muscles of the thigh, leading to weakness in adduction and instability during walking. Answer: (c) Thigh adduction.
6. Which of the following is not a muscle supplied by the obturator nerve?
a) Gracilis
b) Adductor longus
c) Pectineus
d) Obturator externus
Explanation: The pectineus muscle is mainly supplied by the femoral nerve and occasionally by the obturator nerve. However, it is not consistently innervated by it. Answer: (c) Pectineus.
7. During childbirth, compression of which nerve may lead to difficulty in thigh adduction?
a) Obturator nerve
b) Pudendal nerve
c) Femoral nerve
d) Sciatic nerve
Explanation: Prolonged labor or forceps delivery can compress the obturator nerve against the pelvic wall, leading to weakness in adduction and pain in the medial thigh. Answer: (a) Obturator nerve.
8. Which of the following tests is used clinically to assess obturator nerve integrity?
a) Knee jerk reflex
b) Adductor reflex
c) Achilles reflex
d) Patellar reflex
Explanation: The adductor reflex tests the integrity of the obturator nerve (L2–L4). The examiner taps the medial thigh while observing adductor muscle contraction. Answer: (b) Adductor reflex.
9. A patient with obturator nerve injury may also complain of referred pain to:
a) Lateral thigh
b) Medial thigh and knee
c) Posterior leg
d) Anterior thigh
Explanation: Obturator nerve injury often causes referred pain to the medial thigh and knee because of its articular branches to these joints. Answer: (b) Medial thigh and knee.
10. In total hip arthroplasty, inadvertent damage to which nerve causes loss of thigh adduction and medial thigh sensation?
a) Obturator nerve
b) Femoral nerve
c) Sciatic nerve
d) Superior gluteal nerve
Explanation: During hip replacement surgery, the obturator nerve can be injured as it runs along the pelvic wall. This leads to weakness in adduction and sensory loss on the medial thigh. Answer: (a) Obturator nerve.
Chapter: Lower Limb Anatomy; Topic: Femoral Region; Subtopic: Femoral Sheath and Its Contents
Keyword Definitions:
Femoral sheath: A funnel-shaped fascial tube enclosing the femoral artery, femoral vein, and femoral canal.
Femoral canal: The medial compartment of the femoral sheath containing lymphatics and a lymph node.
Femoral nerve: Lies outside the femoral sheath, supplying the anterior thigh muscles.
Femoral artery and vein: Major vessels of the thigh enclosed within the femoral sheath.
Genitofemoral nerve: Divides into genital and femoral branches; lies on psoas major.
Lead Question - 2015
Structure which lies outside the femoral sheath
a) Femoral artery
b) Femoral nerve
c) Femoral vein
d) Genitofemoral nerve
Explanation: The femoral nerve lies outside the femoral sheath, lateral to the femoral artery. The sheath encloses the femoral artery, femoral vein, and femoral canal but not the femoral nerve. The sheath is derived from transversalis and iliac fascia. Its function is to allow smooth movement of vessels during hip flexion. (Answer: b)
1) The medial compartment of the femoral sheath contains
a) Femoral artery
b) Femoral vein
c) Femoral canal
d) Femoral nerve
Explanation: The femoral canal is the medial compartment of the femoral sheath and contains lymphatics and a deep inguinal lymph node called the node of Cloquet. It provides a potential space for venous expansion and can become the site of femoral hernia. (Answer: c)
2) The femoral sheath is derived from
a) Fascia lata
b) Iliac and transversalis fascia
c) Cribriform fascia
d) Deep fascia of thigh
Explanation: The femoral sheath develops from the downward prolongation of the transversalis fascia (anteriorly) and iliac fascia (posteriorly). It surrounds the femoral vessels below the inguinal ligament and facilitates their movement during limb motion. (Answer: b)
3) Femoral sheath encloses all except
a) Femoral artery
b) Femoral vein
c) Femoral nerve
d) Femoral canal
Explanation: The femoral nerve lies outside the femoral sheath. The sheath encloses the artery, vein, and canal. This anatomic relationship is important during femoral hernia repair and vascular catheterization. (Answer: c)
4) The femoral canal transmits
a) Femoral artery
b) Femoral vein
c) Lymphatics and lymph node
d) Femoral nerve
Explanation: The femoral canal transmits lymphatic vessels and the deep inguinal lymph node (node of Cloquet). It allows expansion of the femoral vein and acts as a weak point where femoral hernia can develop. (Answer: c)
5) Which of the following passes through the femoral ring?
a) Femoral artery
b) Femoral vein
c) Lymphatics
d) Femoral nerve
Explanation: The femoral ring is the upper opening of the femoral canal through which lymphatics pass to the external iliac lymph nodes. It is the potential site for femoral hernia. (Answer: c)
6) A 40-year-old woman presents with a swelling below the inguinal ligament, medial to the femoral vein. The most likely diagnosis is
a) Inguinal hernia
b) Femoral hernia
c) Lipoma
d) Lymphadenopathy
Explanation: A swelling below the inguinal ligament and medial to the femoral vein indicates a femoral hernia. It passes through the femoral ring into the canal and appears below the ligament. This type of hernia is more common in females due to a wider pelvis. (Answer: b)
7) The node of Cloquet is located in
a) Femoral canal
b) Inguinal canal
c) Adductor canal
d) Popliteal fossa
Explanation: The node of Cloquet is a deep inguinal lymph node situated within the femoral canal. It is the highest deep inguinal node and connects to external iliac lymph nodes. It helps drain lymph from the lower limb. (Answer: a)
8) A catheter inserted into the femoral artery passes through which structure first?
a) Femoral sheath
b) Cribriform fascia
c) Fascia lata
d) Femoral ring
Explanation: During arterial catheterization, the needle passes through the femoral sheath which surrounds the femoral artery and vein. The sheath allows smooth gliding of vessels during limb movements and protects them from compression. (Answer: a)
9) Which nerve lies lateral to the femoral artery in the femoral triangle?
a) Femoral nerve
b) Obturator nerve
c) Lateral cutaneous nerve of thigh
d) Saphenous nerve
Explanation: The femoral nerve lies lateral to the femoral artery in the femoral triangle. This anatomical relationship is crucial for nerve blocks and vascular access procedures. The nerve divides into muscular and cutaneous branches below the inguinal ligament. (Answer: a)
10) Injury to femoral sheath during surgery may lead to
a) Arterial spasm
b) Venous thrombosis
c) Lymphatic leakage
d) Nerve palsy
Explanation: Damage to the femoral sheath may lead to lymphatic leakage due to injury to lymphatic channels within the femoral canal. It can cause postoperative lymphocele formation. Proper identification and ligation of lymphatic vessels are essential during surgery. (Answer: c)
Chapter: Lower Limb Anatomy; Topic: Knee Joint; Subtopic: Ligaments of Knee Joint and Clinical Correlations
Keyword Definitions:
ACL (Anterior Cruciate Ligament): Prevents anterior displacement of the tibia on the femur; most commonly injured ligament in the knee.
PCL (Posterior Cruciate Ligament): Prevents posterior displacement of the tibia on the femur; stronger than ACL.
MCL (Medial Collateral Ligament): Resists valgus stress; often injured along with medial meniscus.
LCL (Lateral Collateral Ligament): Resists varus stress; not attached to the lateral meniscus.
Knee Joint: A synovial hinge joint between femur, tibia, and patella; allows flexion, extension, and slight rotation.
Lead Question - 2015
Most common ligament damaged in knee injury is
a) ACL
b) PCL
c) MCL
d) LCL
Explanation: The anterior cruciate ligament (ACL) is the most commonly injured ligament of the knee. It prevents anterior translation of the tibia on the femur. ACL injury usually occurs due to sudden deceleration, twisting, or hyperextension during sports. It presents with knee instability and positive Lachman and anterior drawer tests. (Answer: a)
1) Which test is used to assess the integrity of the ACL?
a) Lachman test
b) Posterior drawer test
c) McMurray test
d) Pivot shift test
Explanation: The Lachman test is the most sensitive test for ACL injury. It involves pulling the tibia forward while stabilizing the femur to assess anterior translation. Increased forward movement indicates ACL tear. The pivot shift test also checks for rotational instability caused by ACL deficiency. (Answer: a)
2) Which ligament prevents posterior displacement of the tibia on the femur?
a) ACL
b) PCL
c) MCL
d) LCL
Explanation: The posterior cruciate ligament (PCL) prevents posterior displacement of the tibia relative to the femur. It is stronger than the ACL and is commonly injured in dashboard-type car accidents where the tibia is forced backward. (Answer: b)
3) A football player sustains a blow to the lateral side of the knee. Which structures are likely injured?
a) MCL, medial meniscus, ACL
b) LCL and lateral meniscus
c) PCL and popliteus
d) Quadriceps tendon
Explanation: A blow to the lateral side of the knee stretches the medial side, resulting in injury to the medial collateral ligament (MCL), often accompanied by damage to the medial meniscus and ACL—known as the “unhappy triad” injury pattern. (Answer: a)
4) Which ligament of the knee is attached to the lateral meniscus?
a) ACL
b) PCL
c) MCL
d) LCL
Explanation: The lateral meniscus is not attached to the lateral collateral ligament (LCL). Instead, it is connected to the popliteus tendon, which helps prevent injury. The medial meniscus, however, is firmly attached to the MCL, predisposing it to injury. (Answer: d)
5) Which ligament prevents excessive valgus stress at the knee joint?
a) MCL
b) LCL
c) ACL
d) PCL
Explanation: The medial collateral ligament (MCL) resists valgus stress, which pushes the knee medially. Injury occurs with lateral impact or twisting forces, commonly during football or skiing accidents. It is often associated with medial meniscus and ACL injury. (Answer: a)
6) A 25-year-old athlete hears a “pop” in the knee followed by swelling and instability. Which ligament is most likely torn?
a) ACL
b) PCL
c) MCL
d) LCL
Explanation: A “popping” sound followed by rapid swelling and instability is classic for ACL tear. It often occurs after sudden deceleration or change in direction during sports. Diagnosis is confirmed by MRI or positive Lachman test. (Answer: a)
7) A patient involved in a car accident presents with posterior sagging of the tibia. Which ligament is most likely injured?
a) ACL
b) PCL
c) MCL
d) LCL
Explanation: Posterior sagging of the tibia in a flexed knee indicates a PCL injury. It commonly occurs in dashboard injuries where the tibia strikes the dashboard, forcing it posteriorly. The posterior drawer test helps confirm this diagnosis. (Answer: b)
8) The “unhappy triad” of knee injury includes damage to which three structures?
a) ACL, MCL, Medial meniscus
b) PCL, LCL, Lateral meniscus
c) ACL, LCL, Lateral meniscus
d) PCL, MCL, Medial meniscus
Explanation: The classic unhappy triad involves tears of the ACL, MCL, and medial meniscus. It occurs when a lateral blow to the knee causes valgus stress. This triad leads to instability, pain, and swelling, requiring surgical repair in many cases. (Answer: a)
9) The tibial collateral ligament is also known as
a) Medial collateral ligament
b) Lateral collateral ligament
c) Posterior cruciate ligament
d) Oblique popliteal ligament
Explanation: The tibial collateral ligament is another name for the medial collateral ligament (MCL). It extends from the medial epicondyle of the femur to the medial condyle and shaft of the tibia, providing medial knee stability. (Answer: a)
10) A basketball player presents with knee instability during pivoting movements. Which ligament injury is most likely?
a) ACL
b) PCL
c) MCL
d) LCL
Explanation: Instability during pivoting or twisting is characteristic of an ACL tear. The ACL provides anterior and rotational stability to the knee. Damage results in “giving way” sensations during direction changes, requiring rehabilitation or surgical reconstruction. (Answer: a)
Chapter: Lower Limb Anatomy; Topic: Inguinal Region; Subtopic: Structures Passing Beneath the Inguinal Ligament
Keyword Definitions:
Inguinal Ligament: A fibrous band formed by the lower border of the external oblique aponeurosis, extending from the anterior superior iliac spine (ASIS) to the pubic tubercle.
Femoral Nerve: Major nerve of the anterior thigh passing beneath the inguinal ligament lateral to the femoral artery.
Genitofemoral Nerve: Arises from L1–L2; divides into genital and femoral branches.
Psoas Major: A large muscle of the posterior abdominal wall that passes beneath the inguinal ligament to insert on the femur.
Femoral Vessels: Artery and vein passing through the femoral sheath into the thigh beneath the inguinal ligament.
Lead Question - 2015
Which structure(s) passes behind the inguinal ligament:
a) Femoral branch of genitofemoral nerve
b) Femoral vein
c) Psoas major
d) All
Explanation: All the listed structures pass beneath the inguinal ligament. The femoral nerve, artery, vein, and lymphatics pass from the abdomen into the thigh beneath this ligament. The psoas major muscle lies posterior to the ligament. The femoral branch of the genitofemoral nerve also passes below the ligament to supply the skin over the femoral triangle. (Answer: d)
1) Which muscle forms the floor of the femoral triangle?
a) Pectineus
b) Sartorius
c) Adductor longus
d) Iliacus
Explanation: The floor of the femoral triangle is formed by the iliopsoas laterally and pectineus medially. These muscles provide the base upon which the femoral vessels and nerve lie. The roof is formed by fascia lata, while the boundaries are sartorius, adductor longus, and inguinal ligament. (Answer: a)
2) The femoral nerve passes:
a) Below the inguinal ligament
b) Through the femoral sheath
c) Above the inguinal ligament
d) Behind the femoral vein
Explanation: The femoral nerve passes beneath the inguinal ligament but outside the femoral sheath. It lies lateral to the femoral artery and supplies the anterior thigh muscles. This relationship is clinically important in femoral nerve blocks for anesthesia. (Answer: a)
3) The femoral artery passes under which part of the inguinal ligament?
a) Mid-inguinal point
b) Midpoint of inguinal ligament
c) Lateral one-third
d) Medial one-third
Explanation: The femoral artery passes under the inguinal ligament at the mid-inguinal point, which is the midpoint between the ASIS and pubic symphysis. This point is crucial for palpating the femoral pulse and performing femoral artery catheterization. (Answer: a)
4) The femoral sheath encloses all except:
a) Femoral artery
b) Femoral vein
c) Femoral nerve
d) Femoral canal
Explanation: The femoral sheath is a fascial sleeve enclosing the femoral artery, femoral vein, and femoral canal, but not the femoral nerve. The nerve lies outside the sheath, lateral to the artery. This arrangement allows smooth gliding of vessels during thigh movements. (Answer: c)
5) Which of the following does not pass below the inguinal ligament?
a) Obturator nerve
b) Femoral nerve
c) Iliacus
d) Psoas major
Explanation: The obturator nerve passes through the obturator canal, not beneath the inguinal ligament. In contrast, the femoral nerve, iliacus, and psoas major do pass beneath it into the anterior thigh. (Answer: a)
6) A patient presents with pain in the upper anterior thigh following pelvic surgery. Which nerve is likely affected?
a) Femoral branch of genitofemoral nerve
b) Obturator nerve
c) Femoral nerve
d) Iliohypogastric nerve
Explanation: The femoral branch of the genitofemoral nerve supplies skin over the upper anterior thigh. It can be injured during lower abdominal or pelvic surgery, leading to sensory loss in this area. The nerve passes beneath the inguinal ligament alongside the femoral vessels. (Answer: a)
7) Which of the following passes through the muscular lacuna under the inguinal ligament?
a) Femoral nerve
b) Femoral artery
c) Femoral vein
d) Femoral canal
Explanation: The muscular lacuna beneath the inguinal ligament contains the femoral nerve and iliopsoas muscle, whereas the vascular lacuna contains the femoral vessels and canal. These lacunae are separated by the iliopectineal arch. (Answer: a)
8) A hernia protruding below and lateral to the pubic tubercle is likely:
a) Direct inguinal hernia
b) Indirect inguinal hernia
c) Femoral hernia
d) Obturator hernia
Explanation: A femoral hernia emerges below and lateral to the pubic tubercle through the femoral canal, beneath the inguinal ligament. It is more common in females due to a wider pelvis and femoral canal. It carries a high risk of strangulation. (Answer: c)
9) Which structure separates the femoral nerve from the femoral artery beneath the inguinal ligament?
a) Iliopsoas muscle
b) Pectineus muscle
c) Fascia lata
d) Femoral sheath
Explanation: The iliopsoas muscle separates the femoral nerve (lying lateral) from the femoral artery (lying medial) beneath the inguinal ligament. This anatomical relationship is vital in regional anesthesia and surgical approaches to the femoral triangle. (Answer: a)
10) Which structure passes through the femoral canal?
a) Deep inguinal lymph node
b) Femoral artery
c) Femoral nerve
d) Genitofemoral nerve
Explanation: The femoral canal contains lymphatics and the deep inguinal lymph node (Cloquet’s node). It allows expansion of the femoral vein during increased venous return. The canal is clinically important as the site of femoral hernias. (Answer: a)
Chapter: Pelvis and Perineum Anatomy; Topic: Ischiorectal (Ischioanal) Fossa; Subtopic: Boundaries and Contents of Ischiorectal Fossa
Keyword Definitions:
• Ischiorectal fossa: A wedge-shaped fat-filled space located on either side of the anal canal in the anal triangle.
• Obturator internus: A muscle forming the lateral wall of the pelvis, covered by obturator fascia.
• Pelvic diaphragm: Muscular floor of the pelvis formed mainly by levator ani and coccygeus muscles.
• Pudendal canal: A canal within the obturator fascia that carries pudendal nerve and internal pudendal vessels.
Lead Question – 2015
Lateral border of ischiorectal fossa is formed by?
a) Gluteus maximus
b) Perineal membrane
c) Pelvic diaphragm
d) Obturator internus
Answer: d) Obturator internus
Explanation: The lateral wall of the ischiorectal fossa is formed by the obturator internus muscle covered with its fascia, which contains the pudendal canal. The medial wall is formed by the levator ani and external anal sphincter. The space allows distension of the anal canal during defecation and contains fat and neurovascular structures.
1. The medial wall of the ischiorectal fossa is formed by:
a) Obturator internus
b) Levator ani
c) Gluteus maximus
d) Piriformis
Answer: b) Levator ani
Explanation: The levator ani muscle forms the medial boundary of the ischiorectal fossa, separating it from the anal canal. The fascia over this muscle contributes to the fossa’s structure and supports the rectum, maintaining continence during defecation.
2. Which of the following structures pass through the pudendal canal?
a) Inferior rectal vessels
b) Internal pudendal vessels and pudendal nerve
c) Perineal branch of femoral nerve
d) Inferior gluteal nerve
Answer: b) Internal pudendal vessels and pudendal nerve
Explanation: The pudendal canal (Alcock’s canal) is formed by the obturator fascia and contains the pudendal nerve, internal pudendal artery, and vein. It supplies structures of the perineum and external genitalia.
3. Clinical case: A patient presents with a perianal abscess spreading laterally. The infection is most likely to involve which structure?
a) Ischiorectal fossa
b) Pudendal canal
c) Deep perineal pouch
d) Anal sphincter
Answer: a) Ischiorectal fossa
Explanation: The ischiorectal fossa is a common site for abscess formation because it contains loose areolar tissue and fat. Infection may spread across the midline via the deep postanal space, causing bilateral abscesses requiring drainage.
4. The base of the ischiorectal fossa is formed by:
a) Pelvic diaphragm
b) Perineal skin and fascia
c) Obturator internus
d) Anal sphincter
Answer: b) Perineal skin and fascia
Explanation: The base or inferior boundary of the ischiorectal fossa is formed by the skin and superficial fascia of the perineum. It provides an external limit and can become tender or swollen during abscess formation.
5. The apex of the ischiorectal fossa is directed toward:
a) Pubic symphysis
b) Ischial tuberosity
c) Urogenital diaphragm
d) Pelvic diaphragm
Answer: d) Pelvic diaphragm
Explanation: The apex of the ischiorectal fossa lies superiorly where the obturator internus fascia meets the levator ani muscle. It is a potential site of communication between the pelvic and perineal spaces for spread of infection.
6. Clinical case: A patient develops pain and swelling in the right buttock and anal area. The abscess is found extending to the opposite side. The infection likely spread through:
a) Pudendal canal
b) Deep postanal space
c) Anal sphincter
d) Pelvic diaphragm
Answer: b) Deep postanal space
Explanation: The deep postanal space connects the two ischiorectal fossae posteriorly, allowing infection or abscesses to spread from one side to the other. Prompt surgical drainage prevents systemic infection and fistula formation.
7. Which nerve supplies the skin overlying the ischiorectal fossa?
a) Pudendal nerve
b) Inferior rectal nerve
c) Perineal branch of femoral nerve
d) Posterior femoral cutaneous nerve
Answer: b) Inferior rectal nerve
Explanation: The inferior rectal branch of the pudendal nerve supplies the skin around the anal orifice and the external anal sphincter. It traverses the ischiorectal fossa and is often involved in perianal infections or during surgical interventions.
8. The ischiorectal fossa contains all EXCEPT:
a) Fat
b) Inferior rectal vessels
c) Internal pudendal artery
d) Deep perineal pouch
Answer: d) Deep perineal pouch
Explanation: The deep perineal pouch lies anterior and superior to the ischiorectal fossa. The fossa itself contains fat, inferior rectal vessels and nerves, and the pudendal canal, which runs along its lateral wall.
9. Which muscle forms the roof of the ischiorectal fossa?
a) Levator ani
b) Coccygeus
c) Obturator internus
d) Both a and b
Answer: d) Both a and b
Explanation: The levator ani and coccygeus muscles together form the pelvic diaphragm, which serves as the roof of the ischiorectal fossa. These muscles support pelvic viscera and maintain continence by elevating the anal canal during defecation.
10. Clinical case: During surgical drainage of an ischiorectal abscess, which structure should be avoided to prevent fecal incontinence?
a) External anal sphincter
b) Obturator internus
c) Pudendal canal
d) Perineal membrane
Answer: a) External anal sphincter
Explanation: The external anal sphincter forms part of the medial wall of the ischiorectal fossa. Injury to this muscle during abscess drainage can lead to fecal incontinence. Proper anatomical knowledge ensures safe drainage without compromising continence.
Chapter: Lower Limb Anatomy; Topic: Blood Supply of the Femur; Subtopic: Arterial Supply of Head and Neck of Femur
Keyword Definitions:
• Medial circumflex femoral artery: Supplies the posterior aspect of the neck and head of the femur through retinacular branches.
• Lateral circumflex femoral artery: Supplies the anterior part of the femoral neck and adjacent muscles.
• Profunda femoris artery: Main deep artery of the thigh giving rise to both circumflex branches.
• Retinacular arteries: Small branches providing crucial blood supply to the femoral head.
Lead Question - 2015
Arterial branches which supply the head and neck of the femur is/are:
a) Medial circumflex artery
b) Lateral circumflex artery
c) Profunda femoris artery
d) All
Explanation (Answer: d) All
The medial and lateral circumflex femoral arteries, branches of the profunda femoris artery, supply the head and neck of the femur. The medial circumflex gives retinacular branches that reach the head through the capsule. The lateral circumflex provides anterior support. Their combined contribution maintains femoral head viability, crucial in hip fractures.
1. Which artery gives the main blood supply to the femoral head in adults?
a) Medial circumflex femoral artery
b) Lateral circumflex femoral artery
c) Obturator artery
d) Femoral artery
2. Which artery supplies the ligamentum teres of the femur?
a) Obturator artery
b) Medial circumflex artery
c) Lateral circumflex artery
d) Inferior gluteal artery
3. In fracture neck of femur, avascular necrosis of the head occurs mainly due to injury to:
a) Retinacular arteries
b) Obturator artery
c) Popliteal artery
d) Inferior gluteal artery
4. Which branch of profunda femoris passes between the divisions of femoral nerve?
a) Lateral circumflex femoral artery
b) Medial circumflex femoral artery
c) Descending genicular artery
d) Superior gluteal artery
5. Clinical case: A 60-year-old woman with displaced fracture neck femur develops avascular necrosis. Which artery is most likely damaged?
a) Medial circumflex femoral artery
b) Lateral circumflex femoral artery
c) Profunda femoris artery
d) Inferior epigastric artery
6. The lateral circumflex femoral artery divides into how many branches?
a) Two
b) Three
c) Four
d) One
7. The cruciate anastomosis around the hip involves all except:
a) Inferior gluteal artery
b) Medial circumflex femoral artery
c) Lateral circumflex femoral artery
d) Superior gluteal artery
8. Clinical case: A patient undergoing hip replacement accidentally injures the artery passing posterior to the femoral neck. Which is it?
a) Medial circumflex femoral artery
b) Lateral circumflex femoral artery
c) Obturator artery
d) Deep external pudendal artery
9. Which of the following does NOT participate in trochanteric anastomosis?
a) Superior gluteal artery
b) Inferior gluteal artery
c) Obturator artery
d) Deep circumflex iliac artery
10. Clinical case: A patient has severe hip pain and MRI shows necrosis of femoral head post dislocation. Which vascular network is mainly affected?
a) Retinacular vessels from medial circumflex femoral artery
b) Obturator artery
c) Popliteal artery
d) Inferior gluteal artery
11. Which artery forms the ascending branch that anastomoses around the greater trochanter?
a) Lateral circumflex femoral artery
b) Profunda femoris artery
c) Medial circumflex femoral artery
d) Inferior gluteal artery
Chapter: Lower Limb Anatomy; Topic: Femoral Nerve; Subtopic: Muscular and Sensory Distribution
Keyword Definitions:
• Femoral nerve: The largest branch of the lumbar plexus (L2–L4), supplying the anterior thigh muscles and skin of the anterior and medial leg.
• Pectineus: A flat muscle of the upper thigh that flexes and adducts the hip; mainly supplied by the femoral nerve.
• Obturator externus: A muscle responsible for lateral rotation of the thigh, innervated by the obturator nerve.
• Vastus medialis: A part of the quadriceps group that stabilizes the patella and extends the knee.
Lead Question - 2015
Femoral nerve supplies all except?
a) Pectineus
b) Sartorius
c) Vastus medialis
d) Obturator externus
Explanation (Answer: d) Obturator externus
The femoral nerve (L2–L4) supplies the muscles of the anterior thigh including quadriceps femoris, pectineus (partially), and sartorius. The obturator externus is an exception; it is supplied by the posterior division of the obturator nerve. Understanding these innervations is important in diagnosing nerve injuries affecting hip movements and knee extension strength.
1. Which root values contribute to the formation of the femoral nerve?
a) L1–L3
b) L2–L4
c) L3–L5
d) L4–S1
2. Which of the following is NOT a branch of the femoral nerve in the thigh?
a) Saphenous nerve
b) Muscular branches
c) Obturator branch
d) Articular branches
3. Clinical case: A patient cannot extend the knee after pelvic surgery. Which nerve is most likely injured?
a) Femoral nerve
b) Obturator nerve
c) Sciatic nerve
d) Lateral femoral cutaneous nerve
4. Which of the following muscles receives dual nerve supply from femoral and obturator nerves?
a) Pectineus
b) Sartorius
c) Adductor longus
d) Vastus lateralis
5. Clinical case: A 50-year-old man presents with loss of sensation over the anterior thigh and medial leg. The likely lesion involves?
a) Femoral nerve
b) Obturator nerve
c) Tibial nerve
d) Common peroneal nerve
6. Which of the following is a sensory continuation of the femoral nerve beyond the adductor canal?
a) Saphenous nerve
b) Obturator nerve
c) Lateral femoral cutaneous nerve
d) Ilioinguinal nerve
7. Femoral nerve emerges from the lateral border of which muscle in the abdomen?
a) Psoas major
b) Iliacus
c) Quadratus lumborum
d) Obturator internus
8. Clinical case: During catheterization, the patient feels sharp pain radiating down the anterior thigh. Which structure might be irritated?
a) Femoral nerve
b) Obturator nerve
c) Genitofemoral nerve
d) Iliohypogastric nerve
9. Which of the following statements about the femoral nerve is TRUE?
a) Lies outside the femoral sheath
b) Lies inside the femoral sheath
c) Lies within the femoral canal
d) Passes behind the femoral vein
10. Clinical case: Following trauma to the inguinal region, the patient develops weakness in hip flexion and knee extension. Which nerve is injured?
a) Femoral nerve
b) Obturator nerve
c) Sciatic nerve
d) Lateral cutaneous nerve of thigh
11. Which nerve supplies the skin over the anterior and medial aspects of the thigh?
a) Femoral nerve
b) Obturator nerve
c) Tibial nerve
d) Pudendal nerve
Chapter: Lower Limb Anatomy; Topic: Gluteal Region; Subtopic: Nerve Supply of Gluteal Muscles
Keyword Definitions:
• Superior gluteal nerve: A branch of the sacral plexus (L4–S1) that supplies the gluteus medius, gluteus minimus, and tensor fasciae latae muscles.
• Gluteus maximus: The largest muscle of the body, responsible for hip extension, supplied by the inferior gluteal nerve.
• Tensor fasciae latae: A muscle that assists in abduction and medial rotation of the thigh.
• Gluteus medius and minimus: Muscles that stabilize the pelvis during walking.
Lead Question - 2015
Superior gluteal nerve does not supply?
a) Tensor fasciae latae
b) Gluteus medius
c) Gluteus minimus
d) Gluteus maximus
Explanation (Answer: d) Gluteus maximus
The superior gluteal nerve (L4–S1) supplies the gluteus medius, gluteus minimus, and tensor fasciae latae. It exits through the greater sciatic foramen above the piriformis. The gluteus maximus is supplied by the inferior gluteal nerve (L5–S2), which provides motor control for hip extension and rising from a sitting position. Injury leads to difficulty climbing stairs or standing up.
1. Which nerve supplies the gluteus maximus muscle?
a) Superior gluteal nerve
b) Inferior gluteal nerve
c) Sciatic nerve
d) Pudendal nerve
2. Which muscles are supplied by the superior gluteal nerve?
a) Gluteus medius and minimus
b) Gluteus maximus and medius
c) Tensor fasciae latae and gluteus maximus
d) Piriformis and obturator internus
3. Clinical case: A patient has a waddling gait and pelvic drop on the contralateral side during walking. The lesion involves which nerve?
a) Superior gluteal nerve
b) Inferior gluteal nerve
c) Obturator nerve
d) Femoral nerve
4. The superior gluteal nerve emerges from which spinal segments?
a) L2–L4
b) L4–S1
c) L5–S2
d) S1–S3
5. Clinical case: A patient has difficulty abducting the thigh at the hip. Which muscle is likely paralyzed?
a) Gluteus medius
b) Gluteus maximus
c) Adductor longus
d) Pectineus
6. Which of the following exits through the greater sciatic foramen above the piriformis?
a) Superior gluteal nerve
b) Inferior gluteal nerve
c) Pudendal nerve
d) Sciatic nerve
7. Clinical case: After intramuscular injection in the superomedial quadrant of the gluteal region, a patient develops hip drop. Which nerve was injured?
a) Superior gluteal nerve
b) Inferior gluteal nerve
c) Sciatic nerve
d) Posterior cutaneous nerve of thigh
8. Which muscle acts as both a flexor and abductor of the hip joint?
a) Tensor fasciae latae
b) Gluteus maximus
c) Piriformis
d) Obturator externus
9. Clinical case: A 35-year-old athlete presents with inability to climb stairs after a fall. Which nerve is most likely affected?
a) Inferior gluteal nerve
b) Superior gluteal nerve
c) Obturator nerve
d) Femoral nerve
10. Which muscle, if paralyzed, will result in difficulty maintaining a level pelvis during walking?
a) Gluteus medius
b) Gluteus maximus
c) Adductor magnus
d) Psoas major
11. Trendelenburg sign is due to paralysis of which nerve?
a) Superior gluteal nerve
b) Inferior gluteal nerve
c) Obturator nerve
d) Sciatic nerve
Chapter: Lower Limb Anatomy; Topic: Medial Compartment of Thigh; Subtopic: Adductor Muscles and Their Nerve Supply
Keyword Definitions:
• Adductor muscles: Group of muscles in the medial compartment of the thigh responsible for adduction of the thigh, including adductor longus, brevis, magnus, gracilis, and obturator externus.
• Adductor magnus: The largest adductor muscle, consisting of adductor and hamstring parts.
• Profunda femoris artery: The main blood supply of the adductor compartment.
• Adductor tubercle: A bony prominence on the medial condyle of the femur where the hamstring part of adductor magnus inserts.
Lead Question - 2015
What is true about adductors of thigh –
a) Ischial head of adductor magnus is an adductor
b) Profunda femoris artery is the main blood supply
c) Ischial head of adductor magnus originates from adductor tubercle
d) Adductor magnus is the largest muscle
Explanation (Answer: b) Profunda femoris artery is the main blood supply
The profunda femoris artery provides the chief vascular supply to the adductor muscles of the thigh. The adductor magnus has two parts — adductor (obturator nerve) and hamstring (tibial nerve). The adductor part arises from the inferior pubic ramus, while the hamstring part arises from the ischial tuberosity and inserts into the adductor tubercle. It’s the largest adductor muscle.
1. Which nerve supplies the adductor longus muscle?
a) Femoral nerve
b) Obturator nerve
c) Sciatic nerve
d) Tibial nerve
2. Which artery mainly supplies the adductor muscles of the thigh?
a) Femoral artery
b) Profunda femoris artery
c) Popliteal artery
d) Obturator artery
3. Clinical case: A patient has difficulty bringing thighs together and loss of sensation on the medial thigh. Which nerve is affected?
a) Obturator nerve
b) Femoral nerve
c) Sciatic nerve
d) Pudendal nerve
4. The hamstring part of adductor magnus is supplied by:
a) Tibial part of sciatic nerve
b) Obturator nerve
c) Common peroneal nerve
d) Femoral nerve
5. Which of the following is not part of the adductor group of the thigh?
a) Adductor longus
b) Gracilis
c) Sartorius
d) Adductor brevis
6. Clinical case: A 40-year-old runner complains of pain in the medial thigh after sprinting. Which muscle is most likely strained?
a) Adductor longus
b) Biceps femoris
c) Tensor fasciae latae
d) Rectus femoris
7. Adductor magnus is supplied by:
a) Obturator and tibial nerves
b) Femoral and sciatic nerves
c) Tibial and femoral nerves
d) Common peroneal nerve
8. The opening in the adductor magnus for passage of femoral vessels is called:
a) Adductor canal
b) Adductor hiatus
c) Saphenous opening
d) Obturator foramen
9. Clinical case: Paralysis of the obturator nerve results in:
a) Loss of adduction of the thigh
b) Loss of knee extension
c) Loss of hip flexion
d) Foot drop
10. Which muscle acts both as an adductor and extensor of the thigh?
a) Adductor magnus
b) Adductor longus
c) Gracilis
d) Pectineus
11. The adductor tubercle serves as an attachment for:
a) Hamstring part of adductor magnus
b) Adductor longus
c) Adductor brevis
d) Pectineus
Chapter: Upper Limb Anatomy; Topic: Nerves of Upper Limb; Subtopic: Medial Cutaneous Nerve of Arm
Keyword Definitions:
Radical neck dissection: A surgical procedure for removing lymph nodes and surrounding tissue to treat cancer in the neck.
Medial cutaneous nerve of arm: A branch of the medial cord of the brachial plexus that supplies skin sensation on the medial side of the arm.
Brachial plexus: A network of nerves supplying the upper limb, formed by the anterior rami of C5–T1 spinal nerves.
Thoracodorsal nerve: Nerve supplying the latissimus dorsi muscle, aiding in shoulder adduction and extension.
Long thoracic nerve: Nerve supplying the serratus anterior muscle, important for scapular movement.
Lead Question – 2015
A nerve injured in radical neck dissection leads to loss of sensation in medial side of the arm, nerve injured is?
a) Long thoracic nerve
b) Thoracodorsal nerve
c) Dorsal scapular nerve
d) Medial cutaneous nerve of arm
Explanation: The medial cutaneous nerve of arm (C8–T1) is a branch of the medial cord of the brachial plexus. It supplies sensory innervation to the medial surface of the arm. Injury during radical neck dissection leads to loss of sensation over this region. Other nerves like long thoracic and thoracodorsal are motor nerves, not sensory.
Guessed Questions for NEET PG:
1. Injury to the long thoracic nerve leads to –
a) Winged scapula
b) Loss of arm sensation
c) Shoulder dislocation
d) Loss of elbow flexion
Explanation: The long thoracic nerve supplies the serratus anterior muscle. Its injury results in winging of the scapula due to loss of scapular fixation. Sensory loss does not occur as it is a motor nerve. The correct answer is a) Winged scapula.
2. Which muscle is supplied by the thoracodorsal nerve?
a) Latissimus dorsi
b) Deltoid
c) Trapezius
d) Rhomboid major
Explanation: The thoracodorsal nerve arises from the posterior cord of the brachial plexus and innervates the latissimus dorsi muscle. It helps in shoulder adduction, internal rotation, and extension. Hence, the correct answer is a) Latissimus dorsi.
3. Dorsal scapular nerve injury affects which muscle?
a) Rhomboid major
b) Deltoid
c) Biceps brachii
d) Subscapularis
Explanation: The dorsal scapular nerve supplies rhomboid major, rhomboid minor, and levator scapulae. Injury leads to weak scapular retraction and elevation. The correct answer is a) Rhomboid major.
4. Which nerve is derived from the medial cord of brachial plexus?
a) Medial cutaneous nerve of arm
b) Axillary nerve
c) Musculocutaneous nerve
d) Suprascapular nerve
Explanation: The medial cutaneous nerve of arm is a direct branch of the medial cord (C8–T1). It provides cutaneous sensation to the medial arm. Thus, the correct answer is a) Medial cutaneous nerve of arm.
5. Loss of shoulder adduction indicates injury to –
a) Thoracodorsal nerve
b) Axillary nerve
c) Suprascapular nerve
d) Musculocutaneous nerve
Explanation: Shoulder adduction is primarily by the latissimus dorsi, innervated by the thoracodorsal nerve. Hence, injury to this nerve causes weakness in adduction. The correct answer is a) Thoracodorsal nerve.
6. Clinical Case: A patient develops winged scapula after axillary lymph node dissection. Which nerve is likely injured?
a) Long thoracic nerve
b) Axillary nerve
c) Median nerve
d) Radial nerve
Explanation: The long thoracic nerve supplies the serratus anterior muscle. Damage during axillary surgery causes winging of the scapula, as the muscle can no longer hold the scapula against the thoracic wall. The correct answer is a) Long thoracic nerve.
7. Clinical Case: A patient presents with loss of sensation over the medial side of the arm following trauma to the axilla. Which nerve is injured?
a) Medial cutaneous nerve of arm
b) Lateral cutaneous nerve of forearm
c) Ulnar nerve
d) Musculocutaneous nerve
Explanation: The medial cutaneous nerve of arm provides sensation to the medial aspect of the arm. Injury in the axilla or during lymph node dissection can cause sensory loss in that region. Hence, the correct answer is a) Medial cutaneous nerve of arm.
8. Clinical Case: A patient after trauma to the neck shows difficulty in raising the shoulder. Which nerve is likely involved?
a) Spinal accessory nerve
b) Axillary nerve
c) Dorsal scapular nerve
d) Suprascapular nerve
Explanation: The spinal accessory nerve supplies the trapezius muscle, responsible for shoulder elevation. Injury during neck surgery causes shoulder droop and difficulty elevating the shoulder. The correct answer is a) Spinal accessory nerve.
9. Clinical Case: Injury to the posterior cord of the brachial plexus causes paralysis of which muscle?
a) Latissimus dorsi
b) Deltoid
c) Both a and b
d) None
Explanation: The posterior cord gives rise to the axillary and thoracodorsal nerves, which supply deltoid and latissimus dorsi respectively. Hence, both muscles are affected. The correct answer is c) Both a and b.
10. Clinical Case: Following breast surgery, a woman complains of difficulty in reaching forward and scapular winging. Which nerve was injured?
a) Long thoracic nerve
b) Thoracodorsal nerve
c) Axillary nerve
d) Median nerve
Explanation: The long thoracic nerve injury leads to paralysis of the serratus anterior muscle. This causes winging of the scapula and difficulty in forward arm movement. The correct answer is a) Long thoracic nerve.