Prolotherapy is an injection-based complementary and alternative medical therapy for chronic musculoskeletal pain. It has been used for approximately 100 years, however, its modern applications can be traced to the 1950s when the prolotherapy injection protocols were formalized by George Hackett, a general surgeon in the U.S. The name prolotherapy is based on the presumed “proliferative” effects on chronically injured tissue. It has also been called “regenerative injection therapy.”
Prolotherapy treatment commonly consists of several injection sessions delivered every 1 week to 4 weeks over the course of several months. During an individual prolotherapy session, therapeutic solutions are injected at sites of painful and tender ligament and tendon insertions, or in adjacent joint spaces. Injected solutions (“proliferants”) is used to cause local irritation, with subsequent inflammation and tissue healing, resulting in enlargement and strengthening of damaged ligamentous, tendon and intra-articular structures. These processes were thought to improve joint stability, biomechanics, function and ultimately, to decrease pain. The potential of prolotherapy to stimulate release of growth factors favoring soft tissue healing has also been suggested as a possible mechanism.
Prolotherapy has been best assessed as a treatment for low back pain, osteoarthritis and tendinopathy, each of which is a significant cause of pain and disability, and is often refractory to best standard-of-care therapies.
Low back pain
In the Ongley study1, the intervention and control groups differed markedly on the make-up of initial injections and type of spinal manipulation associated with the injections. Significantly more subjects in the prolotherapy (88%) group reported at least 50% reduction in pain severity compared to controls (39%). Also, prolotherapy subjects, compared to controls, reported significantly decreased pain and disability levels.
Reeves et al. assessed prolotherapy as a treatment for knee and finger OA.2 Subjects with finger or knee pain and radiological evidence of OA were randomly assigned to receive 3 injection sessions of either prolotherapy with dextrose and lidocaine, or lidocaine and bacteriostatic water (control group). In the finger OA trial, intervention subjects significantly improved in ‘pain with movement’ and ‘flexion range’ scores compared to controls; pain scores at rest and with grip showed a tendency to improvement. In the knee OA trial, subjects in both groups reported significant improvements in pain and swelling scores, number of buckling episodes, and flexion range of motion compared to baseline. At 12-month follow-up in both studies showed improved radiological features of OA on plain x-ray films: authors reported decreased joint space narrowing and osteophyte grade in the finger study, and increased patellofemoral cartilage thickness in the knee study. These radiological findings may suggest disease modification properties of prolotherapy.