Swelling of the upper extremity, function and muscle strength of shoulder joint following mastectomy combined with radiotherapy.

Swelling of the arm, mobility of the shoulder joint and muscle strength were examined in 76 patients with breast cancer 4.5 to 14 years (mean 8 years) after primary therapy. Marked arm swelling was found on the operated side in 31% of the patients operated by radical mastectomy and in 18% of those having undergone total mastectomy. The swelling was more marked in the upper arm than in the forearm. Patients irradiated postoperatively with a megavoltage technique showed more often and more oedema than those treated with a kilovoltage technique. Obese patients had more swelling than patients of normal weight. Of the various movements of the shoulder joint, abduction, adduction, flexion, extension, horizontal extension and internal rotation were significantly reduced on the operated side in comparison with the non-operated side, but the differences were not great. Neither swelling of the arm nor the patient's weight had any effect on the function of the shoulder joint, as expressed in terms of abduction. Of the muscle groups in the shoulder joint adductors, flexors and extensors were significantly weaker on the operated than on the non-operated side. The muscle strength of the operated side averaged 25% weaker than that of the control side. Swelling of the arm did not reduce the muscle strength of the shoulder joint.