Does motor control training improve pain and function in adults with symptomatic lumbar disc herniation? A systematic review and meta-analysis of 861 subjects in 16 trials

Key points

1. 01Motor control training (MCT) teaches low-level sustained activation of deep trunk muscles (multifidus, transversus abdominis, pelvic floor) to correct movement faults and reduce loading on the lumbar spine.
2. 02Across 16 trials with 861 participants, MCT tended to outperform comparators such as TENS, general exercises, conventional care, and minimal intervention for pain and function.
3. 03In non-surgical patients, MCT produced a clinically meaningful short-term pain reduction versus TENS (MD -28.85, 95% CI -40.04 to -17.66), though the authors note the robustness of this finding was poor.
4. 04Large favorable effects on function were seen both before and after surgery, but each comparison rested on only 1 to 3 small studies.
5. 05Certainty of evidence was very low to low and 14 of 16 trials had high risk of bias, so results should be interpreted with caution.

How it was conducted

Design

Systematic review and random-effects meta-analysis of clinical trials with concurrent comparison groups (PROSPERO CRD42016038166)

Search

Eight databases plus ClinicalTrials.gov from inception to April 2021; 6,695 records screened

Participants

16 trials with 861 participants who had symptomatic lumbar disc herniation, with and without surgery

Intervention

Motor control training vs other physiotherapist-led interventions (eg TENS, general exercises, conventional care), minimal or no intervention, or surgery

Outcomes

Pain intensity (mean difference) and functional status (standardised mean difference); certainty by GRADE

What they found

• 16 trials (861 participants) were eligible; 14 had high risk of bias and 2 had some risk of bias.
• Non-surgical patients, pain at short-term: MCT vs TENS gave a clinically meaningful reduction (MD -28.85, 95% CI -40.04 to -17.66; n=69, 2 studies), but robustness was poor.
• Non-surgical patients, function: MCT favored over traditional general exercises at long-term (SMD -0.83, 95% CI -1.35 to -0.31; n=63, 1 study) and over TENS at short-term (SMD -1.43, 95% CI -2.41 to -0.46; n=69, 2 studies).
• Post-surgical patients, function at short-term: MCT favored over general exercises (SMD -0.95, 95% CI -1.32 to -0.58; n=124, 3 studies), conventional treatment (SMD -2.30, 95% CI -2.96 to -1.64; n=60, 1 study), and minimal intervention (SMD -1.34, 95% CI -1.87 to -0.81; n=68, 2 studies).
• No trial compared MCT with surgery; overall certainty of evidence was very low to low.

Limitations

• Few high-quality trials per comparison, with 14 of 16 studies at high risk of bias, making results inconclusive.
• Several comparisons rested on a single small study, and the pain-versus-TENS finding had poor robustness.
• Effect data could not be extracted from several trials, and sample sizes were generally not pre-specified.
• No study compared MCT directly with surgery, leaving that clinically important question unanswered.

Why it matters

For patients

Core-focused motor control exercises may help reduce sciatica-type back pain and improve function from a disc herniation, whether or not you have had surgery.

For clinicians

MCT is a reasonable conservative option for lumbar disc herniation, but the very low certainty means it should not be presented as clearly superior to alternatives.

For readers

The signal favors motor control training, yet high risk of bias and tiny per-comparison samples keep the evidence weak.