Any amounts which may be paid or payable by the said cities under the provisions of any workers’ compensation or similar law to a member or to the dependents of a member on account of any temporary total disability, permanent total disability or death shall be offset against and payable in lieu of any periodic benefits payable out of the retirement system on account of the same disability or death. In case the present value of the total commuted benefits under said workers’ compensation or similar law is less than the actuarial equivalent of the benefits otherwise payable from the retirement system, then the present value of the commuted payments shall be deducted from the actuarial equivalent of the benefits and such benefits as may be provided by the retirement system so reduced.