Table 3.
Description of study characteristics of randomized controlled epidural trials assessing the efficacy of caudal epidural injections in lumbar disc herniation.
| Study | Study characteristics | Methodologic quality score | Number of patients | Interventions | Outcome measures | Pain and function improvement | Improvement | Comment(s) | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 months | 6 months | 12 months | Short term (≤ 6 months) | Long term | ||||||||
| > 6 months | ≥ 12 months | |||||||||||
| Manchikanti et al. [85, 86] (2012, 2011) | RA, AC, F | 10/12 | Total = 120 | Lidocaine vs lidocaine mixed with steroid Number of injections = 1–5 | NRS, ODI, employment status, opioid intake | 62% vs 72% | 72% vs 73% | 67% vs 72% | Y | Y | Y | Double-blind study showing improvement |
| Ackerman and Ahmad [1] (2007) | RA, AC, F | 7/12 | Total = 90 Caudal = 30 IL = 30 TF = 30 |
Methylprednisolone + saline Number of injections = 1–3 |
Numeric pain score (0–10), rating of pain relief, ODI, BDI, contrast dispersion pattern | Caudal = 57% IL = 60% TF = 283% |
Caudal = 57% IL = 60% TF = 83% |
NA | Y | Y | NA | Study showing mid-term improvement |
| Dashfield et al. [29] (2205) | RA, AC, F | 9/12 | Total = 60 Caudal = 30 Endoscopy = 30 |
Lidocaine with triamcinolone Number of injections = 1 |
Pain relief, SF-MPQ, HADS scores | SI | SI | NA | Y | Y | NA | Study showing mid-term improvement |
| Iversen et al. [50] (2011) | RA, PC, UL | 6/12 | Total = 116 | Saline or triamcinolone acetonide with saline Number of injections = 2 |
ODI, EQLS, VAS | N | N | N | U | U | U | Study with numerous deficiencies with flawed design and without local anesthetic showing lack of improvement |
| Murakibhavi and Khemka [95] (2011) | RA, AC, B | 7/12 | Group A = 50 control conservative management Group B = 52 caudal epidural steroid injections Total = 102 |
Conservative management or caudal epidural steroid injections | VAS, ODI, BDI, NPI | Group A = 32% Group B = 92% |
Group A = 24% Group B = 86% |
NA | Y | Y | NA | Moderate-quality study showing short-term improvement |
RA = randomized; AC = active control; F = fluoroscopy; PC = placebo control; UL = ultrasound; B = blinded; IL = interlaminar; TF = transforaminal; NRS = Numeric Rating Scale; ODI = Oswestry Disability Index; BDI = Beck Depression Inventory; SF-MPQ = Short-Form McGill Pain Questionnaire; HADS = Hospital Anxiety and Depression Scale; EQLS = European Quality of Life Scale; NPI = Numerical Pain Intensity; SI = significant improvement; N = no; NA = not applicable; Y = yes; U = unclear.