G2142 HCPCS - FUNCTIONAL STATUS MEASURED BY THE OSWESTRY DISABILITY INDEX (ODI VERSION 2.1A) AT ONE YEAR (9 TO 15 MONTHS) POSTOPERATIVELY WAS LESS THAN OR EQUAL TO 22 OR FUNCTIONAL STATUS MEASURED BY THE ODI VERSION 2.1A WITHIN THREE MONTHS PREOPERATIVELY AND AT ONE YEAR (9 TO 15 MONTHS) POSTOPERATIVELY DEMONSTRATED AN IMPROVEMENT OF 30 POINTS OR GREATER