Six RCTs (439 adults) and 34 case reports, case series and non- randomised controlled trials (3,831 children and adults) were included.
The RCTs were of a high quality, scoring 4 or 5 out of 5 on the Jadad scale and 7 to 9 out of 9 on the Delphi internal validity assessment.
Osteoarthritis: 2 RCTs were identified. One study found that PrT (with dextrose plus lidocaine) significantly improved finger movement (p=0.027) and the range of finger flexion (p=0.003) compared with lidocaine plus bacteriostatic water, but found no significant difference between treatments for pain at rest or grip. The other study of knee osteoarthritis found that both treatments significantly improved pain scores, swelling, buckling episodes and flexion compared with baseline.
Low back pain (4 RCTs): the results were mixed. Two RCTs found PrT preceded by injected steroids, manipulation and exercise significantly increased the proportion of patients with >50% improvement compared with control (88% versus 39% with pain reduction, p<0.03l and 77% versus 53% with reduction in pain score or disability, p=0.04). The other 2 RCTs found no significant difference between PrT alone and control in pain or somatic perception scores (1 RCT) or between a non-standard PrT injection protocol and control in pain and disability (the largest and highest quality RCT).
Adverse effects (6 RCTs): the studies suggested that PrT (as used in the included studies) was associated with short-term pain and irritation at the injection site.
Case reports, case series and non-randomised controlled trials (34 studies).
Taken all together, the studies reported positive subjective outcomes with few adverse effects.
Two non-randomised controlled trials reported positive effects with PrT in low back pain. One found PrT non statistically significantly improved response rate compared with control. The other found significant improvements in pain and leg pain and non significantly decreased disability and back pain compared with conservative treatment.