Isokinetic strength after tears of the supraspinatus tendon.
We measured the isokinetic strength of abduction, adduction, internal rotation, and external rotation in ten patients with full-thickness tears of the supraspinatus and ten with partial-thickness tears. The measurements were repeated after intra-articular or intrabursal injection of local anaesthetic. Pain blocks produced significant increases in strength in both full and partial-thickness tears. After the block, the strength in full-thickness tears compared with the opposite side was 67% to 81% in abduction and 67% to 78% in external rotation, both significantly smaller than those on the uninvolved side (p = 0.0064, p = 0.0170). In partial-thickness tears the strength after the block ranged from 82% to 111%, with no significant differences between the involved and uninvolved sides. The decreases in strength of 19% to 33% in abduction and 22% to 33% in external rotation after full-thickness tears appear to represent the contribution of supraspinatus to the strength of the shoulder.
Itoi
E
E
Department of Orthopedic Surgery, Akita University School of Medicine, Japan.
Minagawa
H
H
Sato
T
T
Sato
K
K
Tabata
S
S
D000328:Adult; D000368:Aged; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008875:Middle Aged; D012399:Rotation; D017006:Rotator Cuff / Q000601:surgery; D000070636:Rotator Cuff Injuries; D012782:Shoulder / Q000503:physiopathology*