MATERIALS AND METHODS

All outpatient fluoroscopically guided facet injections at a single institution during a 54-month period were retrospectively and independently reviewed by 2 musculoskeletal (MSK) trained radiologists. All intra-articular, all periarticular, and partial intra-/periarticular injection locations were determined. Periarticular and partial peri-/intra-articular injections were combined for analysis. Preinjection, immediate, and 1-week postinjection numeric pain scores, patient age, sex, anesthetic/steroid mixture, fluoroscopic time, and physician performing the procedure were recorded.

RESULTS

Seventy-seven patients (mean age, 51.1 years) had 100 procedures with 205 total facet joints injected. All intra-articular, all periarticular, and partial peri-/intra-articular injections constituted 54%, 20%, and 26% of the cases, respectively. The immediate and 1-week postprocedural change in pain was −3.7 (95% CI, −4.5 to −2.8; P < .001) and −1.4 (95% CI, −2.2 to −0.6; P = .001) for the all intra-articular and −3.6 (95% CI, −4.4 to −2.9; P < .001) and −1.2 (95% CI, −1.9 to −0.4; P = .002) for the combined group. Changes in immediate pain were significantly associated with the prepain level (P < .001) and patient age (P = .024) but not with the anesthetic used. Analyses revealed no significant difference in pain reduction between the groups either immediately or 1 week postinjection. Intra-articular injections required less fluoroscopic time (geometric mean, 39 versus 52 seconds) (P = .005).

CONCLUSIONS

Intra-articular and periarticular fluoroscopically guided facet injections provide statistically significant and similar pain relief both immediately and 1 week postinjection.

Given the variety of presentations and factors that contribute to low back pain, determining the optimal treatment method may be challenging. The facet joint is 1 possible etiology of axial low back pain with both surgical and nonsurgical treatment methods used to provide pain relief.1 Facet-mediated pain or “facet syndrome” may account for up to 45% of cases of axial low back pain.2 The characteristic pain in facet syndrome is located in the low back with involvement of the buttock/greater trochanteric region with occasional unilateral extension along the lateral thigh.1,2 The pain is usually more pronounced after immobilization and with low back extension.2 The injection of a local anesthetic is often used to both diagnose and manage facet-mediated pain.1,2 Even though there is a paucity of literature to support the use of intra-articular steroid injections in this patient population, corticosteroids are often injected to provide longer term pain relief and restore functional status.3–12 Whether intra-articular or periarticular placement of the injectate substantially alters the efficacy of the injection is also debated.4,7,8 Therefore, we retrospectively evaluated patients with fluoroscopically guided facet injections for clinically suspected facet syndrome to determine the immediate and short-term efficacy of those injections and to evaluate whether an intra-articular or periarticular injection provided greater pain relief.