Abstract
Objective
To identify any difference in clinical outcome between Intra-Capsular facet (IF) and Peri-facet (PF) injections in patients with low back pain (LBP). IF and PF joint steroid injections have been used for treatment of LBP with varied reports of pain relief for many years.
Methods
Patients randomised into IF and PF groups. Bilateral L4/5 and L5/S1 levels injected. 40mg of Depo-Medrone with Lignocaine (total 1ml) in IF group. 80mg of Depo-Medrone with 1ml of 0.5% Chirocaine (total 3ml) in PF group. Pain visual analogue score (VAS) and analgesic chart – completed till six months.
Results
Eighty eight total, 14 withdrew, 69 with feedback available. Sixty-three (91%) had significant pain relief a week following injection, 86% and 94% in IF & PF groups. Mean duration of pain relief was 12.4 weeks (IF-12.2, PF-12.5). Mean change in VAS before & after injection was 4 (IF-4, PF-4). Mean change in analgesic use before & after injection was 2 tablets. (IF-2.9, PF-2.3). Radiation dose area product (DAP) for IF injections- 603 and PF- 45 mGy.cm2. 45 (51%) came for repeat injections, 19 & 26 in IF & PF groups.
Conclusions
Majority of patients had pain relief with no statistically significant difference between 2 groups in change in pain severity, duration of pain relief or change in analgesic intake.
Significant change in VAS after injection in both groups (from 7 to 3). Pain relief for a mean duration of 12.4 weeks.
PF - technically easier- 9 patients randomised to IF group had to have PF injections (facet joint osteophytes).
Radiation doses much higher for IF injections even in expert hands (P=0.007). It took double the time to perform IF injections compared to PF (30 and 15 minutes).
