Our aim was to describe the atypical pattern of increased fatty
degeneration in the infraspinatus muscle compared with the supraspinatus
in patients with a massive rotator cuff tear. We also wished to
describe the nerve conduction and electromyography findings in these
patients. A cohort of patients undergoing surgery for a massive rotator
cuff tear was identified and their clinical records obtained. Their
MRI images were reviewed to ascertain the degree of retraction of
the torn infraspinatus and supraspinatus muscles, and the degree
of fatty degeneration in both muscles was recorded. Nerve conduction studies
were also performed in those patients who showed more degeneration
in the infraspinatus than in the supraspinatus.Aims
Patients and Methods
Although many clinical and experimental investigations have shed
light on muscle atrophy and intramuscular accumulation of fat after
rotator cuff disruption, none have reported on their onset in the
absence of muscle retraction. In 30 rabbits, we detached one supraspinatus (SSP) tendon and
repaired it immediately, thus preventing muscle retraction. The
animals were killed in groups of 10 at one, two and six weeks. Both
shoulders of 15 non-operated rabbits served as controls. We measured
the weight and volume of SSP muscles and quantified the cross-sectional
area of intramuscular fat (i-fat) histologically.Objectives
Methods
