As with arthroplasty of other large joints, shoulder replacement reliably improves a patient’s quality of life. However, although shoulder replacement is frequently successful, complications do occur. Injury to the subscapularis can lead to weakness, decreased motion and stability, and diminished satisfaction following shoulder arthroplasty. Compromise or dysfunction of the subscapularis resulting from routine division and repair during the arthroplasty is a complication that is being recognized more frequently. Subscapularis dysfunction may lead to a loss of active terminal internal rotation with an abnormal belly-press or lift-off test or the inability to perform a shirt-tuck test. In a recent study, >65% of patients had subscapularis dysfunction following shoulder arthroplasty with a soft-tissue subscapularis repair.