Possible long thoracic nerve problem?

Hi everyone,

I saw a thirty year old lady last week who suffered a fall from her bicycle 2 months ago, whereby the wheels jammed and she fell onto her left hand side.

She complains of a left 'dead arm' and slight ache along the superior border of her left scapula. The dead arm is most noticable when driving and she tends to hold onto the bottom of the steering wheel. When she lies on her left side the arm goes numb straight away. She didn't have any other specific aggs as she tends not to use the arm so much.

On examination, she has a slight winging of the left scapula which becomes more noticeable on eccentric activity. Actively she cannot abduct/flex the arm for the last 20 degrees or so, but this can be gained passively by bringing the scapula into abduction and medial rotation. She had reduced sensation in dermatomes C5-T1 but full power (except in serratus anterior, obviously). ULTT's were negative. I have not yet examined the cervical or thoracic spines.

She has had UL and neck X rays which were fine. An orthopaedic surgeon thinks she may have a problem with the long thoracic nerve and has referred her for an EMG. Her osteopath hasn't helped either.

I'm wondering just how the long thoracic nerve could have been isolated in the mechanism of injury (if this is the diagnosis) without damage to other parts of the brachial plexus? Has anyone had a similar experience or can offer any advice at all? I really don't know where to go with her!

Many thanks in advance.

"I have not yet examined the cervical or thoracic spines."

Why not?, seems the most obvious place to begin an exam given her symptoms.

Hello Lucin ;
I encounter like these traumatic nerve injuries around the shoulder and scapulothoracic region . I had seem something like your patient and a supraspinatus nerve injury .

The Point of specifity nerve injury could occur in case of comperssion aetiologies , but I think in case of traction/stretching injuries no rule specific e.g. in Erb's palsy .
The progress / outcome according to the degree of nerve injury ,but I like to raise point PAIN around shoulder could disable the patient from abduction to the degree the practionner imagine it is nerve / paralysis .

cheers
Emad

Hi lucinda,

I would agree with Ginger - but it sounds like you had your hands full with getting through your shoulder assessment etc.

Your question is why just the long thoracic nerve.

Who knows why it got injured and not other parts of the brachial plexus.

Perhaps - and this is purely guessing - it was because she knew she was falling, held her arm out to stop the fall, suffered a retraction injury in trying to stabilise her shoulder when the weight landed on the outstretched arm and then caused some long thoracic nerve injury when serratus anterior failed to stabilise?

Good luck!

LTN is cervical plexus - very flimsey structurely compared to nerves of the brachial plexus. Susceptable to nerve compression around the neck (middle scalene) and along it's superficial course.
Look out for very overdeveloped scapular and rotator cuff muscles that are doing compensatory supportive role.

:)

G

You should also perform assement of cervical spine and thoracic spine. From whatever you have described, it seems to be a brachial plexus injury with sensory involvement and motor involvement predominently affecting the long thoracic nerve (C5,6,7). Long thoracic nerve arises from nerve roots and it is proximal injury.

hi friend
your discription gives a picture likely of root level injury of brachial plexus.in traumatic injuries of brachial plexus,it wont follow a specific pattern.as suggested by others a detailed evaluation of cervical and thoracic spine should be done.also check for the sensation and tenderness in periscapular region,mmt of scapular muscles.
neural assessment should follow the pattern of
root level
trunk level
cord level
peripheral nerve level

please let us know the details of the same,cheers

I am wondering, it seems a lot of guessing is going on. This while there is no evidence of full exam. Everyone seems to think the worst of it while the question is how the thoracic nerve can be isolated. Well can it with the information we have at the moment? I would think no. But a full examination of all movements of arm, spine (T and C), nerve testing and strength might reveal far more. A fall on an outstretched arm could cause problems at the wrist, elbow, shoulder, scapula:thoracal and cervical for example.