抄録
Recently it was reported that suprascapular nerve injury may contribute to infraspinatus muscle atrophy after rotator cuff tear. The purpose of this study was to investigate whether suprascapular nerve injury contributes to infraspinatus muscle atrophy after rotator cuff tear.
We examined 18 shoulders (12 males, 6 females) which had occurred infraspinatus muscle atrophy after rotator cuff tear from July, 2006 to April, 2008.
Their ages were 51-76 years old(average : 63.2 years old ).
The period from injury to examination was from 1 to 42 months (average : 7.2 months).
We performed needle electromyogram on supraspinatus and infraspinatus, and evaluated it.
There was no evidence of suprascapular nerve injury with electromyogram in these patients. In all 18 patients, electromyogram findings showed normal insertional activity and no denervation potentials.
If suprascapular nerve injury contributed to infraspinatus muscle atrophy after rotator cuff tear, the electromyogram findings should have shown abnormal wave, but it was absent at this time.
In this study, we could not determine because of small symptom example number.
However, we think that the possibility which suprascapular nerve injury contributes to infraspinatus muscle atrophy after rotator cuff tear is low.