Section 58. Any employee of the commonwealth eligible to receive workers' compensation under chapter one hundred and fifty-two who sustains injuries while in the employ of the commonwealth and who has sufficient sick leave credits accrued shall be granted leave of absence with pay for each working day he is absent from his duties because of such injuries until he returns to work or until the case has been approved by the industrial accident board.
Workers' compensation for such period shall be refunded to the state treasurer or spending agency of the commonwealth. The payment by the industrial accident board for such period shall constitute the total refund and the employee shall be credited with the proportionate part of sick leave credits represented by the workers' compensation paid by the industrial accident board.
If the industrial accident board refuses to accept jurisdiction over the case the employee shall not be granted leave with pay in excess of his accumulated sick leave credits or vacation leave.
Notwithstanding the provisions of this section, an employee who, while in the performance of duty, receives bodily injuries resulting from acts of violence of patients or prisoners in his custody, and who as a result of such injury would be entitled to benefits under said chapter one hundred and fifty-two, shall be paid the difference between the weekly cash benefits to which he would be entitled under said chapter one hundred and fifty-two and his regular salary, without such absence being charged against available sick leave credits, even if such absence may be for less than eight calendar days' duration.