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A 15 year old boy has suffered an injury to his right leg while playing soccer. He also noticed that he frequently trips over while walking thereafter. Physical examination should a tense swollen right lower extremitiy and a bruise over the upper lateral part of the shin area. Dorsiflexion is weakened and decreased sensation between the first and second big toes were also noticed. Which of the following nerves was most likely affected by this compartment syndrome?

A- Deep fibular
B- Superficial fibular
C- Common peroneal
D- Tibial
E- Femoral
 

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I aggree with you Sharer.
The features are totally coincide with common peroneal nerve.
The sensation defect highlights superficial peroneal nerve.
 

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Answer is A.

The answer is A- Deep Fibular Nerve

Mechanism of injury is to the lateral upper shin, which is also the differential for deep fibular nerve injury (lateral knee).

Signs are also consistent with damage to that nerve: foot drop (loss of dorsiflexion of foot), slight difficulty walking since there is decrease in motor finction of all anterior leg muscles (can't extend digits) and lastly the deep fibular nerve provides the sensory innervation to the webspace between the hallux and the second digit.
 

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C) Common peroneal

peroneal1.gif
click image to enlarge

Common Peroneal Nerve Injury

The peroneal nerve is a branch of the sciatic nerve, which supplies movement and sensation to the lower leg, foot and toes.

Common causes of damage to the peroneal nerve include the following:

Trauma or injury to the knee

Fracture of the fibula (a bone of the lower leg)

Use of a tight plaster cast (or other long-term constriction) of the lower leg
Habitual leg crossing

Regularly wearing high boots

Pressure to the knee from positions during deep sleep or coma

Injury during knee surgery.

People who are extremely thin or emaciated (for example, from anorexia nervosa) have a higher-than-normal risk of common peroneal nerve injury.

Conditions such as diabetic neuropathy or polyarteritis nodosa, as well as exposure to certain toxins, can also cause damage to the common peroneal nerve.

Symptoms

Decreased sensation, numbness or tingling in the top of the foot or the outer part of the upper or lower leg

Weakness of the ankles or feet

Walking abnormalities

"Slapping" gait (walking pattern in which each step taken makes a slapping noise)

Foot drop (unable to hold foot horizontal)

Toes drag while walking
 

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A or C? I think A

It's actually a pretty hard question. I would want to pick the common peroneal, since I believe that that is the most likely of these lesions to have resulted from a kick to the outside upper leg. However, the question stem says that the nerve injury is from the compartment syndrome rather than direct injury! I think that because of this, the deep peroneal (fibular) nerve is the most likely answer, since both it and the blood supply run between the anterior compartment and the interosseous membrane and would be impinged upon by the expanding compartment. Also, the neurological symptoms only seem to point to the deep peroneal n.

Let's get an x-ray and a measure the compartment pressure...
 

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The answer should be A (deep fibular), reason is bcuz there's loss of sensation at the lateral part, fibular bone is located at the lateral aspect of the leg and decrease dorsiflexion that means the muscle on the lateral aspect of the leg has been injured, i.e. nerve supplying it has been injured.
 

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i agree with sona. Site makes me think common peroneal but symptoms are that of deep peroneal. So which one to choose ? I guess deep ?
 

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A- Deep fibular ( deep peroneal nerve ), branch of common peroneal nerve,
supplies muscles of anterior compartment of leg - tibialis anterior, extensor digitorum longus, extensor hallucis longus and peroneus tertius,
and an articular branch to ankle joint.

After its bifurcation past the ankle joint, the lateral branch of the deep fibular nerve innervates extensor digitorum brevis and extensor hallucis brevis while the medial branch goes on to provide cutaneous innervation to the webbing between the first and second digits.
 

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Buzz word loss of sensation b/w 1st and 2nd toe deep fibulae/ deep peroneal nerve

Sup peroneal>> loss of dorsal foot sensation+ inability to evert foot
 

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why the hell he/she hasn't posted the answer yet???????:mad::mad::mad:
Don't be mad :)) The answer by what authority? Qbanks and qbook writers have no special knowledge that we don't have. I think that if you really read them, we have more to learn from the responses of the other members, what they would choose and their reasoning, than we would from knowing what was given as the "right" answer.
 
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