Lower Limb Practice Questions

Q: The common peroneal nerve can be rolled against which part of the fibula?

Neck. The **common peroneal nerve** (also known as the common fibular nerve) is a terminal branch of the sciatic nerve. It descends through the popliteal fossa and winds laterally around the **neck of the fibula**. At this specific anatomical location, the nerve lies subcutaneously, resting directly against the bone before dividing into its deep and superficial branches. This superficial position makes it easily palpable (it can be "rolled" against the bone) but also highly susceptible to compression and trauma. **Analysis of Options:** * **Neck (Correct):** This is the narrow portion just below the head. The nerve curves around the lateral aspect of the neck to enter the peroneus longus muscle. * **Styloid process:** This is the pointed apex of the fibular head. It serves as an attachment point for the fibular collateral ligament and biceps femoris tendon, but the nerve passes inferior to it. * **Head:** While the nerve passes posterior to the head, it is not as tightly bound or palpable against the bone here as it is at the neck. * **Shaft:** The nerve has already bifurcated into its terminal branches by the time it reaches the mid-shaft of the fibula. **Clinical Pearls for NEET-PG:** * **Foot Drop:** Injury to the nerve at the fibular neck results in paralysis of the anterior and lateral compartment muscles, leading to loss of dorsiflexion and eversion. * **Sensory Loss:** Patients typically present with anesthesia over the lateral leg and the dorsum of the foot. * **Common Causes:** Tight plaster casts, crossing legs for prolonged periods, or fractures of the proximal fibula. * **Nerve Type:** It is the most commonly injured nerve in the lower limb.

Q: Which of the following is also known as the peripheral heart?

Soleus muscle. **Explanation:** The **Soleus muscle** is famously referred to as the **"Peripheral Heart"** because of its critical role in venous return from the lower limbs [1]. Unlike the superficial gastrocnemius, the soleus contains large, non-valvular venous sinuses (soleal sinuses). When the muscle contracts during walking or standing, it compresses these sinuses, pumping deoxygenated blood upward against gravity toward the heart. This mechanism is the primary driver of the **musculovenous pump** of the leg [1]. **Analysis of Options:** * **Soleus (Correct):** It is a multipennate muscle with a high density of slow-twitch fibers, making it fatigue-resistant and ideal for maintaining postural stability and continuous venous pumping [1]. * **Gastrocnemius:** While it contributes to the calf pump [1], it lacks the extensive venous sinuses found in the soleus. It is primarily a fast-twitch muscle used for explosive movements like jumping. * **Plantaris:** A vestigial muscle with a very short belly and a long tendon (the "freshman's nerve"). It has negligible contractile power and no significant role in venous return. * **Popliteus:** Known as the "Key to the knee," its primary function is to unlock the knee joint by laterally rotating the femur on the fixed tibia. **Clinical Pearls for NEET-PG:** 1. **Soleal Sinuses & DVT:** The soleal sinuses are the most common site for the initiation of **Deep Vein Thrombosis (DVT)** due to stasis during prolonged immobility. 2. **Triceps Surae:** Together, the two heads of the gastrocnemius and the soleus form the *Triceps Surae*, which inserts into the calcaneus via the Tendo Achilles. 3. **Safety Valve:** The venous pump of the calf can generate pressures over 100 mmHg to overcome hydrostatic pressure [1].

Q: When a patient gets up from a sitting position, which of the following events takes place in the knee joint?

Medial rotation of the femur on a fixed tibia. ### Explanation The question describes the **"Locking Mechanism"** of the knee joint. When a person rises from a sitting position to a standing position, the knee moves from flexion to full extension. **1. Why Option A is Correct:** In the final stages of knee extension (the last 30 degrees), the medial condyle of the femur is longer than the lateral condyle. To achieve full extension and maximum stability, the femur must undergo **medial rotation on a fixed tibia** (closed chain movement). This "screws" the joint into a stable, locked position where the ligaments are taut, allowing a person to stand for long periods with minimal muscular effort. **2. Why the Other Options are Incorrect:** * **Option B:** Lateral rotation of the femur on a fixed tibia is the **"Unlocking"** mechanism. This is initiated by the **Popliteus muscle** when moving from a standing to a sitting position. * **Option C & D:** These describe "Open Chain" movements (where the foot is off the ground). In an open chain (e.g., kicking a ball), locking occurs via **lateral rotation of the tibia** on a fixed femur. However, rising from a chair is a "Closed Chain" movement because the feet are fixed on the floor. **3. High-Yield Clinical Pearls for NEET-PG:** * **The "Key" to the Knee:** The **Popliteus muscle** is known as the "Key" because it unlocks the knee by laterally rotating the femur on the tibia. * **Locking vs. Unlocking:** * **Locking:** Extension + Medial rotation of femur (Closed Chain). * **Unlocking:** Flexion + Lateral rotation of femur (Closed Chain). * **Cruciate Ligaments:** During locking, both the Anterior Cruciate Ligament (ACL) and Posterior Cruciate Ligament (PCL) become taut.

Q: What is another name for the spring ligament?

Calcaneonavicular ligament. The **Spring Ligament** is a critical structure in the anatomy of the foot, specifically known as the **Plantar Calcaneonavicular Ligament**. ### Why Option A is Correct The spring ligament connects the **sustentaculum tali** of the calcaneus to the plantar surface of the **navicular bone**. It is called the "spring" ligament because it is composed of dense fibroelastic tissue that supports the head of the talus. Its primary function is to maintain the **medial longitudinal arch** of the foot by preventing the talus from dropping downward and medially under the weight of the body. ### Why Other Options are Incorrect * **B. Calcaneocuboid ligament:** This refers to the short and long plantar ligaments. While they support the lateral longitudinal arch, they do not support the head of the talus. * **C. Transverse tibiofibular ligament:** This is part of the distal tibiofibular syndesmosis at the ankle joint, preventing the separation of the tibia and fibula. * **D. Talocalcaneal ligament:** These ligaments (interosseous, medial, lateral) stabilize the subtalar joint but do not form the "spring" mechanism for the arch. ### NEET-PG High-Yield Pearls * **Clinical Correlation:** Chronic stretching or rupture of the spring ligament leads to **Pes Planus (Flat Foot)**, as the head of the talus descends. * **The "Keystone":** In the medial longitudinal arch, the **Talus** is the keystone, but the spring ligament is the main static stabilizer. * **Anatomical Relation:** The tendon of the **Tibialis Posterior** muscle passes immediately inferior to the spring ligament, providing additional dynamic support to the arch.

Q: A 46-year-old woman stepped on a broken wine bottle, and sharp glass entered the posterior part of her foot. Physical examination concluded that her lateral plantar nerve had been transected. Which of the following conditions will most likely be confirmed by physical examination?

Paralysis of the interossei and adductor hallucis. ### Explanation The **lateral plantar nerve (LPN)**, a branch of the tibial nerve, is functionally analogous to the **ulnar nerve** in the hand. It supplies the majority of the intrinsic muscles of the foot and provides sensation to the lateral 1.5 digits. #### Why the Correct Answer is Right: * **Muscular Supply:** The LPN supplies the **adductor hallucis**, all **interossei** (plantar and dorsal), the lateral three lumbricals, and the muscles of the little toe (abductor, flexor, and opponens digiti minimi). * **Mechanism:** Transection of the LPN leads to denervation of these muscles, resulting in paralysis of the interossei (responsible for abduction/adduction of toes) and the adductor hallucis. #### Why Other Options are Wrong: * **Option A:** Sensation over the plantar surface of the **third toe** is provided by the **medial plantar nerve** (which covers the medial 3.5 digits). The LPN covers the lateral 1.5 digits (5th and lateral half of 4th). * **Option B:** The **abductor hallucis** is supplied by the **medial plantar nerve** (analogous to the median nerve in the hand). * **Option D:** The **flexor hallucis brevis** is primarily supplied by the **medial plantar nerve**. (Note: The LPN may occasionally supply the lateral head, but the medial plantar nerve is the primary driver). #### High-Yield Clinical Pearls for NEET-PG: * **The "Rule of 4":** The **Medial Plantar Nerve** supplies only **4** muscles: 1. Abductor hallucis 2. Flexor digitorum brevis 3. Flexor hallucis brevis 4. First lumbrical * **The Lateral Plantar Nerve** supplies **all other** intrinsic muscles of the foot. * **Sensory Split:** The division between medial and lateral plantar nerves occurs at the midline of the **4th digit**. * **Clinical Correlation:** Injury to the LPN often presents with "clawing" of the toes due to the loss of interossei and lumbrical function.

Q: Which nerve supplies the gluteus medius?

Superior Gluteal Nerve. **Explanation:** The **Superior Gluteal Nerve (L4, L5, S1)** is a branch of the sacral plexus. It exits the pelvis through the greater sciatic foramen, passing *above* the piriformis muscle. It provides motor innervation to three specific muscles: the **Gluteus Medius**, **Gluteus Minimus**, and the **Tensor Fasciae Latae (TFL)**. These muscles are the primary abductors and medial rotators of the hip. **Analysis of Incorrect Options:** * **B. Inferior Gluteal Nerve (L5, S1, S2):** This nerve exits *below* the piriformis and exclusively supplies the **Gluteus Maximus**, the chief extensor of the hip. * **C. Nerve to Obturator Internus (L5, S1, S2):** Supplies the Obturator Internus and the Superior Gemellus. * **D. Nerve to Quadratus Femoris (L4, L5, S1):** Supplies the Quadratus Femoris and the Inferior Gemellus. **High-Yield Clinical Pearls for NEET-PG:** 1. **Trendelenburg Sign:** Injury to the superior gluteal nerve (often due to misplaced intramuscular injections or hip surgery) leads to paralysis of the gluteus medius and minimus. This results in the pelvis dropping on the unsupported side when the patient stands on the affected leg. 2. **Lurching Gait:** To compensate for the pelvic drop, the patient tilts their trunk toward the affected side (compensated Trendelenburg gait). 3. **The "Safe Zone":** Intramuscular injections are given in the **upper outer quadrant** of the gluteal region to avoid injuring the sciatic nerve and the gluteal nerves.

Q: The peroneal artery is a branch of which artery?

Posterior tibial artery. **Explanation:** The **peroneal artery** (also known as the fibular artery) is the largest and most important branch of the **posterior tibial artery**. It typically arises approximately 2.5 cm distal to the lower border of the popliteus muscle. It descends along the medial aspect of the fibula, supplying the lateral compartment of the leg and the calcaneal region. **Analysis of Options:** * **Posterior Tibial Artery (Correct):** After the popliteal artery divides into the anterior and posterior tibial arteries, the posterior tibial artery gives off the peroneal artery via the **tibioperoneal trunk**. * **Anterior Tibial Artery:** This artery passes forward through the opening in the interosseous membrane to supply the anterior compartment. It does not give rise to the peroneal artery. * **Popliteal Artery:** This is the parent trunk that terminates at the lower border of the popliteus by dividing into the anterior and posterior tibial arteries. It does not directly branch into the peroneal artery. * **Arcuate Artery:** This is a branch of the dorsalis pedis artery (the continuation of the anterior tibial artery) located on the dorsum of the foot. **High-Yield Clinical Pearls for NEET-PG:** * **Nutrient Artery:** The peroneal artery provides the nutrient artery to the **fibula**, making the fibula a common site for vascularized bone grafts. * **Termination:** It ends by dividing into the calcaneal branches. * **Tibioperoneal Trunk:** This is the segment of the posterior tibial artery between the origin of the anterior tibial artery and the origin of the peroneal artery. Its occlusion can lead to significant ischemia of both the posterior and lateral compartments.

Question 1

The common peroneal nerve can be rolled against which part of the fibula?

Accepted Answer

Neck

Answer

Styloid process

Answer

Head

Answer

Shaft

Question 2

Which of the following is also known as the peripheral heart?

Accepted Answer

Soleus muscle

Answer

Gastrocnemius muscle

Answer

Plantaris muscle

Answer

Popliteus muscle

Question 3

The patellar plexus is formed by which artery?

Accepted Answer

All of the above

Answer

Descending genicular artery

Answer

Anterior tibial recurrent artery

Answer

Posterior tibial recurrent artery

Question 4

When a patient gets up from a sitting position, which of the following events takes place in the knee joint?

Accepted Answer

Medial rotation of the femur on a fixed tibia

Answer

Lateral rotation of the femur on a fixed tibia

Answer

Medial rotation of the tibia on a fixed femur

Answer

Lateral rotation of the tibia on a fixed femur

Question 5

An elderly woman was admitted with a fracture of the neck of the right femur which failed to unite. On examination, avascular necrosis of the head of the femur was noted. The condition most probably resulted from damage to which of the following?

Accepted Answer

Retinacular branches of the circumflex femoral arteries

Answer

Superior gluteal artery

Answer

Inferior gluteal artery

Answer

Acetabular branch of the obturator artery

Question 6

What is another name for the spring ligament?

Accepted Answer

Calcaneonavicular ligament

Answer

Calcaneocuboid ligament

Answer

Transverse tibiofibular ligament

Answer

Talocalcaneal ligament

Question 7

A 46-year-old woman stepped on a broken wine bottle, and sharp glass entered the posterior part of her foot. Physical examination concluded that her lateral plantar nerve had been transected. Which of the following conditions will most likely be confirmed by physical examination?

Accepted Answer

Paralysis of the interossei and adductor hallucis

Answer

Loss of sensation over the plantar surface of the third toe

Answer

Paralysis of the abductor hallucis

Answer

Flexor hallucis brevis paralysis

Question 8

Which of the following statements about the Anterior Cruciate Ligament (ACL) is true?

Accepted Answer

It prevents posterior dislocation of the femur on the tibia.

Answer

It attaches to the posterior part of the intercondylar area of the tibia.

Answer

It is stronger than the posterior cruciate ligament.

Answer

It attaches upward, backward, and laterally to the posterior aspect of the lateral surface of the medial femoral condyle.

Question 9

Which nerve supplies the gluteus medius?

Accepted Answer

Superior Gluteal Nerve

Answer

Inferior Gluteal Nerve

Answer

Nerve to Obturator Internus

Answer

Nerve to Quadratus Femoris

Question 10

The peroneal artery is a branch of which artery?

Accepted Answer

Posterior tibial artery

Answer

Anterior tibial artery

Answer

Popliteal artery

Answer

Arcuate artery

Lower Limb — MCQs

Lower Limb — MCQs

On this page

Practice by Chapter

Want unlimited practice?