Amends the Workers' Compensation Act. Provides that, in computing the compensation to be paid to an employee who, before the accident for which the employee claims compensation, had before that time sustained an injury resulting in a permanency award or settlement, the award or settlement shall be deducted from any award made for the subsequent injury. Provides that, if an employee received an award or settlement for a shoulder injury between 2012 and the effective date of the amendatory Act, then the award or settlement shall be converted to the appropriate number of weeks for an arm and the credit taken against any award or settlement shall be taken on the arm. Effective immediately.