I just had a case like this.  (permission to post)

The things I checked were:

Latch/Position
Mother's feeling of let down
Milk ejection reflex - heavy/hard/light/slow
Site of breast pain
Is there back pain as well?
Baby's affect during nursing - tense, calm, frustrated...

Things I observed or mother reported

Blanching at base of nipple as if baby were clamping down on it
Heavy letdown (mother collects up to 10mls in a breast shell)
Baby sputters and never relaxed at breast and mother reports that he sometimes has milk come up through his nose.
Mother has cysts at 8:00 and 4:00 which throb
Shooting pain in mid upper back 
Baby had slight tongue tie, which I described as being posterior because he could point his tongue but when extended his tongue to latch it bunched up.

Solutions:

I had mother put a tennis ball behind her back and lean against it as she breastfed to ease the spasm in her back.  
Adjusted the latch and position. Removed all of the pillows she was using
Encouraged her express a few mls prior to latch - which she did do, but with limited success.  She had received some poor advice earlier about pumping after feeding and was having oversupply issues as well.  So she was still drowning her babe on one side.
We used a nipple shield effectively to help babe train his tongue into position and improve the latch.  
Mother is going to an acupuncturist today actually to try and reduce the inflammation.

Conclusions:
The cysts that she had prenatally irritated the 4th intercostal nerve.  This inflammation coupled with her oversupply issue and heavy/hard MER and the babe's solution of clamping down to prevent drowning created the cycle of pain.  Short term use of nipple shield, awareness of latch and use of tennis ball to massage back spasms have improved her experience significantly.

Lea Rivera Todaro, MPhil, IBCLC

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