RESUMO
Objective To observe efficacy of percutaneous laser disc decompression (PLDD) and its correlation with plasma levels of β-endorphine and substance P in patients suffering from protrusion of lumbar intervertebral disc (PLIVD). Methods Seventy-eight patients with PLIVD were randomly divided into two groups, one group (40 patients) treated with PLDD and the other (38 patients) treated with lumbar spine traction and physical therapy as control. Their peripheral plasma levels of β-endorphine and substance P were measured before the procedure and one day, one week and four weeks after it, respectively.Meanwhile, the visual analogue scale (VAS)was applied to assess their pain index. Results Plasma level of substance P was (186±66) ng/L and (419±82) ng/L, and (127 +83) ng/L and (322 +47) ng/L,in treatment and control groups, one day and one week after the procedure, respectively, and that of β-endorphine was (313 ±27) mg/L and (187 ±56) mg/L, and (364 + 18) mg/L and (211 +39) mg/L,one day and one week after it, respectively ( all P ＜ 0. 01 ), with its clinical efficacy of 90% (36/40)and 66% (25/38) one week after it, respectively ( P ＜ 0. 01 ) . Four weeks after it, plasma level of substance P was (64 ±50) ng/L in treatment group as compare to that in controls (93 ±75) ng/L, and that of β-endorphine was (410 ± 21 ) mg/L and (317 ± 42 ) mg/L, respectively, with efficacy of 95% (38/40) and 84% (32/38), respectively. Conclusions Plasma level of substance P can be reduced and that of β-endorphine can be increased by PLDD in patients with PLIVD, thus relieving their pain.Measurements of substance P and β-endorphine can be used as objective indicators to evaluate clinical efficacy of PLDD.