Table 1.
Study characteristics.
| Author | Study design | No. of patients | No. US-guided blocks | Injectate | Technique | Levels blocked (number of blocks) | Confirmation method |
|---|---|---|---|---|---|---|---|
| Medial branch block | |||||||
| Batalov3 2013 | Single-arm cohort | 35 | 176 | 1 mL 0.25% bupivacaine and 5 mg methylprednisolone | US-guided “facet nerve block,” technique not specified | L2–L5 spinal levels; 17 unilateral, 18 bilateral | None |
| Chen6 2020 | Case report | 1 | 2 | 0.25 mL, content not described | Transverse view to determine target (junction of SAP and superior border of TP), lateral to medial in-plane injection, longitudinal view to confirm location | L2 MBB and L3 MBB | None |
| Etheridge14 2020 | Single-arm cohort | 115 | 100 (15 patients excluded due to inability to visualize target) | 0.5 mL 0.75% bupivacaine | Longitudinal view to determine level, transverse view to locate L4 MBB target (junction of the cephalad TP and SAP), lateral to medial in-plane injection; subsequent redirection of needle medially and caudally for L5 MBB while tracking progress in a sagittal view | L4 MBB (100), L5 MBB (100); all unilateral | Fluoroscopic needle position and contrast to validate position of L5 MBB only |
| Greher17 2004 | Case series | 5 | 28 | 1 mL 0.25% bupivacaine | Longitudinal view to determine level, transverse view to determine target (junction of the cephalad TP and SAP), in-plane injection, lateral to medial, verification with longitudinal view | L2 MBB (8), L3 MBB (10), L4 MBB (10); all bilateral | Fluoroscopic needle position |
| Han20 2017 | Retrospective comparative | 146 (US group: 68, FL group: 78) | 94 | 0.5 mL 1% lidocaine and 2.5 mg dexamethasone | Longitudinal scan to determine level, transverse view to determine target (junction of cephalad TP and SAP and junction of SAP and sacral ala); L5 MBB occasionally performed in out-of-plane fashion if sacral ala obstructed field of view | L3 MBB, L4 MBB, L5 MBB; number at each level not specified, number of unilateral and bilateral cases not specified | None |
| Hashemi21 2017 | Single-arm cohort | 30 | 89 | 1 mL 1% lidocaine and 40 mg triamcinolone | Longitudinal view to determine level, transverse view to determine target (junction of the cephalad TP and SAP), lateral to medial in-plane injection | L3 MBB (30), L4 MBB (31), L5 MBB (28); number of unilateral and bilateral cases not specified | Fluoroscopic needle position |
| Jung24 2012 | Single-arm cohort | 50 | 95 | 1 mL 2% lidocaine and 40 mg triamcinolone | Longitudinal view to determine level, transverse view to locate target (junction superior TP and SAP), lateral to medial in-plane injection | T12 MBB (1), L1 MBB (1), L2 MBB (3), L3 MBB (35), L4 MBB (48), L5 MBB (7); number of unilateral and bilateral cases not specified | Fluoroscopic needle position and contrast |
| Moon32 2013 | Single-arm cohort | 27 | 27 patients, total number of blocks not reported | 0.5% lidocaine | Transverse view to identify target (groove at root of TP and base of SAP) | Blocks performed at L1-L5; specific levels blocked are unclear; number of unilateral and bilateral cases not specified | None |
| Rauch37 2009 | Single-arm cohort | 20 | 84 | 0.3 mL mixture of 1% lidocaine and steroid | Longitudinal view to determine level, transverse to determine target, lateral to medial in-plane injection | L3 MBB (28), L4 MBB (29), L5 MBB (35); number of unilateral and bilateral cases not specified | Fluoroscopic needle position |
| Shim43 2006 | Self-controlled cohort | 20 | 101 | 1 mL 0.25% bupivacaine | Parasagittal view to determine level, transverse view to determine target (junction of cephalad TP and SAP), parasagittal view to confirm placement | T12 MBB (4), L1 MBB (22), L2 MBB (35), L4 MBB (31); number at L3 not reported but calculated to be 9 based on total number of blocks; number of unilateral and bilateral cases not specified | Fluoroscopic needle position and contrast |
| Soni47 2018 | Single-arm cohort | 30 | 74 | 0.5 mL 2% lidocaine | US-guided MBB, technique not specified | Levels and laterality not specified | Fluoroscopic needle position and contrast (contrast not specifically mentioned in text but is noted on included confirmatory imaging) |
| Facet joint injection | |||||||
| Constantinescu9 2017 | Case series | 3 | 3 patients, total number of blocks not reported | Local anesthetic and steroid | Intra-articular placement verified by US, views not specified | Not specified | None |
| Erdogan13 2019 | Single-arm cohort | 22 | 61 | 1 mL 2% lidocaine and 40 mg triamcinolone | Longitudinal view to determine level, transverse view with in-plane injection to superolateral corner of facet joint | Unilateral L3-4 (7), bilateral L3-4 (8), unilateral L4-5 (6), bilateral L4-5 (13), unilateral L5-S1 (4), bilateral L5-S1 (4); 6 levels could not be fully or partially visualized by US, although the specific levels were not specified | Fluoroscopic needle position and contrast |
| Galiano16 2007 | RCT | 40 (US group: 20, CT group: 20) | 20 | 1 mL 1% lidocaine, 1 mL 0.5% bupivacaine, and 4 mg betamethasone; 3 mL total volume | Parasagittal view to determine level, transverse view with in-plane injection to facet joint | L3-4 (1), L4-5 (6), L5-S1 (13); facet joints not able to be identified in 2 patients (level not specified), facets only partially identified in 2 other patients (level not specified) | CT needle position |
| Ha19 2010 | RCT | 105 (US group: 54, control group: 51) | 108 | 2% lidocaine and dexamethasone; 0.5 mL total volume | Parasagittal image to determine level, transverse view with in-plane injection | Bilateral L2-3 (3), bilateral L3-4 (15), bilateral L4-5 (28), bilateral L5-S1 (8) | None |
| Karkucak25 2020 | RCT | 49 (US group: 25, palpation-guided: 24) | 38 | 1% lidocaine and 10–20 mg triamcinolone per level; 1–2 mL total volume; 2nd injection performed at 2 wk | Parasagittal view to determine level, transverse view to determine target, lateral to medial in-plane injection | Unilateral L4-5 (18), unilateral L5-S1 (16), bilateral L5-S1 (2); 2 patients in US group did not complete the study | None |
| Kullmer28 1997 | Single-arm cohort | 78 | 213 | 5 mL carbostesin in combination with corticosteroids | Transverse and longitudinal views to visualize facet joint; caudal to cranial in-plane injection | Bilateral L5-S1 (56), unilateral L5-S1 (2), unilateral L4-5 (1), bilateral L4-5 (46), bilateral L3-4 (3) | None |
| Sadeghian40 2018 | Case series | 10 | 18 | 5 mg bupivacaine and 40 mg methylprednisolone | Longitudinal view to determine level, transverse view with in-plane injection | L4-5 and L5-S1, number of blocks per level not specified | None |
| Santiago41 2014 | Case report | 3 | 3 | 0.25% bupivacaine and 10 mg methylprednisolone; 1 mL total volume | Longitudinal view to determine level, transverse view with out-of-plane injection | L1-2 (1), L2-3 (1), L3-4 (1) | Fluoroscopic needle position and contrast |
| Wen51 2014 | RCT | 20 (US group: 10, CT group: 10) | 37 | 0.5% lidocaine, 1–2 mL of analgesic solution | Facet joint identified with ultrasound in transverse plane, otherwise unspecified | Not specified | CT needle position |
| Ye54 2018 | RCT | 40 (US group: 20, CT group: 20) | 74 | 0.5 mL 2% lidocaine and 4 mg betamethasone; 2 mL total volume | Longitudinal view to determine level, transverse view to visualize facet joint | Not specified | CT needle position |
| Yun55 2012 | RCT | 57 (US group: 25, control group: 32) | 81 | 2 mL 1% lidocaine and 10 mg triamcinolone | Parasagittal view to identify level, transverse view with lateral to medial in-plane injection to midpoint of facet joint | Unilateral L4-5 (6), bilateral L4-5 (18), unilateral L5-S1 (5), bilateral L5-S1 (17) | None |
BMI, body mass index; FL, fluoroscopic; FJI, facet joint injection; MBB, medial branch block; SAP, superior articular process; TP, transverse process; RCT, randomized controlled trial; US, ultrasound.