Postoperative Assessment by Using a Torque Machine (BIODEX) and MRIs in Patients treated for a Recurrent Anterior Dislocation or Subluxation of the Shoulder by HATA Yukihiko MURAKAMI Narumichi Department of Rehabilitation Medicine, Shinshu University School of Medicine SEKI Hiroshi, KOBAYASHI Hirokazu and TAKAOKA Kunio Department of Orthopedic Surgery, Shinshu University School of Medicine The recovering process of the operated shoulder function was observed in 21 shoulders of 21 patients who underwent surgery for a recurrent anterior dislocation or subluxation of the shoulder. Putti-Platt procedure was carried out in the affected shoulder and none of the 21 patients demonstrated a recurrence of the shoulder dislocation or subluxation after surgery. The muscle powers were measured at 6 months, and one year postoperatively using a torque machine (BIODEX) after confirming the patients at level 5 in the manual muscle testing without having any apprehension of a dislocation. The power was measured on the affected and unaffected shoulders in both of the directions of flexion/extension, and external rotation/internal rotation at 90 degrees abduction at 2 speeds of 60 degrees/second and 180 degrees/second. The measured values were compared between the affected and unaffected shoulders for statistically significant differences. The cross-sectional area of the subscapularis muscle was measured on MRI transverse images and the values obtained preoperatively, 6 months postoperatively, and one year postoperatively were compared to each other. The peak torque/body weight (%) 6 months postoperatively was significantly smaller in the affected shoulder than that in the unaffected shoulder when the patient actively internally rotated his shoulder at 90 degrees abduction at a speed of 60 degrees/second (p<0.0l). But the power appeared to recover one year postoperatively since there was no significant difference one year after the operation. No significant differences were detected among the cross-sectional area of the subscapularis muscle before the operation, 6 months postoperatively, and one year postoperatively. Postoperative assessment of the muscular power by a torque machine (BIODEX) appears to be more sensitive a method than the measurement of the cross-sectional muscle area on MRI in observing the postoperative recovering process of the shoulder function in the patients with a dislocation or subluxation. -353-
The Shoulder Joint, 2001 ; Vol. 25, No2 : 353-357. -354-
Peak torque/body weight (%) -355-
The Shoulder Joint, 2001 ; Vol. 25, Nat : 353-357. -356-
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