Objectives: The current study aimed to compare the efficiency of epidural injection of methylprednisolone (M) with or without hyaluronidase (H) in treating patients with failed back surgery syndrome.
Patients & Methods: The study included 60 patients with history of previous spine surgery and had persisting pain for >6 months with a leg pain severity of ≥60 on pain visual analogue scale (VAS) and pronounced epidural fibrosis surrounding the nerve root as judged by MRI examination. Both back pain and leg pain were evaluated separately using 0-100 point pain VAS with zero= no pain and 100= worst intolerable pain. Impact of pain on daily life activities was evaluated using the modified Oswestry Disability Questionnaire (ODQ) with higher total score indicates worse function. All patients received epidural injection of 100μg fentanyl plus 120mg methylprednisolone solution (Solu-medrol) in 20ml saline in group M and 120mg methylprednisolone solution and 1500 units hyaluronidase in 20ml saline in group H+M. All patients were assigned to receive 2 injection-settings one-week apart of the same medications. Follow-up consisted of evaluation of back and leg pain scores, disability score and the need for analgesics at 1, 3, 6 and 12 months after the second injection-setting.
Results: The mean duration of symptoms of 9.2±3.1; range: 4-16 months. During injection, discomfort was reported in 24 patients (40%); 14 in group H+M and 10 in group M and burning sensation in the lower limb was experienced in 3 patients in group H+M. The number of patients experienced pain relief of either low back or leg pain showed gradual decrease in both groups, however, there was a significant increase of number of patients experienced pain relief in H+M group compared to M group. Mean low-back pain VAS scores were significantly lower in H+M group at 3-, 6- and 12-months after injection compared to M group, while the difference was non-significant at 1-month after injection, but in favor of H+M group. Mean leg pain VAS scores were significantly lower in H+M group compared to M group throughout the observation period. Moreover, number of patients required analgesia at home showed a significant increase in M group compared to H+M group. Mean disability scores were significantly lower in H+M group compared to pre-injection scores throughout the observation period, while in group M were significantly lower till 6-m after injection and the difference was non-significantly better at 12-months after injection compared to pre-injection scores. In both groups, the lowest DS scores were reported at one month after injection and increased thereafter. Group H+M showed significantly lower DS scores until 6-m after injection compared to M group, but at 12-months after injection the difference was non-significant but in favor of H+M group.
Conclusion: The obtained results confirm the benefits of percutaneous epidural adhesiolysis as part of an overall pain management strategy with a superior outcome with the use of hyaluronidase in combination with methylprednisolone. |
