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Prolotherapy: A nontraditional approach to knee osteoarthritis
Dextrose injections into the knee can reduce pain and improve a patient’s quality of life.
Carlton J. Covey, MD, FAAFP
Marvin H. Sineath Jr., MD, CAQSM
Joseph F. Penta, MD, CAQSM
Jeffrey C. Leggit, MD, CAQSM
Uniformed Services University of the Health Sciences, Bethesda, Md (Drs. Covey and Leggit); Nellis Family Medicine Residency, Nellis Air Force Base, Nev (Dr. Sineath Jr); Naval Hospital Pensacola, Fla (Dr. Penta)
carlton.covey@usuhs.edu
The authors reported no potential conflict of interest relevant to this article.
The opinions and assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the US Air Force, Navy, or Army medical departments.
Knee osteoarthritis: Pain level and movement improve (SOR A)
In a study of patients with knee osteoarthritis (OA) and pain lasting 6 months or more, participants received bimonthly injections of either DPT with lidocaine or lidocaine alone. At 12 months, only those in the DPT group had achieved significant improvement in VAS pain score (44%), self-reported swelling (63%), and knee flexion (14%).11
A more recent study randomized 90 adults with painful knee OA of at least 3 months’ duration to blinded injection (either DPT or saline) or at-home exercise.9 The injections involved both intra- and extra-articular techniques, performed monthly for a total of 3 to 5 injections. At 52 weeks, the DPT group had improved scores on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) by 15.3 points compared with the saline group (7.6 points) and the exercise-only group (8.2 points).
Half of those receiving DPT improved by 12 or more points, compared with less than a third of those receiving saline and a quarter of those treated with exercise alone. Knee Pain Scale (KPS)-based pain frequency and severity were also significantly reduced in the DPT group vs both comparison groups.9
Finger OA. One small randomized study tested the efficacy of DPT in patients with symptomatic finger OA affecting the distal or proximal interphalangeal joint or the trapeziometacarpal (thumb) joint.23 Participants received either DPT with xylocaine or xylocaine alone. Injections were done on the medial and lateral aspects of the affected joints at baseline, 2, and 4 months. Pain (VAS score) during active finger movement improved by 45% in the DPT group vs 15% in the group treated with xylocaine alone. After 6 months, those in the xylocaine-only group received the DPT protocol, and their pain reduction scores rose, on average, from 18% to 54%.23
Low back pain: Little help for chronic condition (SOR A)
Early studies of DPT for the treatment of low back pain had conflicting results. In 2004, the largest (N=110) and most rigorous study of DPT for chronic non-specific low back pain to date12 found no significant improvement.
Participants received either DPT or normal saline injections into tender lumbopelvic ligaments every 2 weeks for a total of 6 treatments. They were then randomized to either core and low back strengthening exercises or normal activity for 6 months. At 12 months, VAS pain and disability scores significantly decreased from baseline in all the groups, with a decline ranging from 26% to 44% for pain and 30% to 44% for disability. However, at no point were there significant differences between injection groups or activity groups.12
A 2007 Cochrane review found insufficient evidence to support the use of DPT alone for the treatment of non-specific low back pain but suggested that, as an adjunct, it may improve pain and disability scores.13 And in 2011, a Cochrane review confirmed that there was insufficient evidence for the use of DPT in sub-acute and chronic low back pain.14 Other studies on the use of DPT for specific low back conditions, including sacroiliac joint pain,24,25 coccydynia,26 and degenerative disc disease,27 have shown trends toward improvement in pain scores24-27 and disability,25 but only one of these was a randomized controlled trial (RCT).25
Lateral epicondylosis: More effective than saline (SOR B)
A single RCT compared DPT to placebo in patients with 6 months of moderate to severe lateral epicondylosis who had failed conservative treatment. Patients received 3 injections of either hypertonic dextrose or saline tendon insertions every 4 weeks, with needle touching bone at the supracondylar ridge, lateral epicondyle, and annular ligament.15 Patients randomly assigned to DPT experienced significant pain relief from baseline to 16 weeks, with a Likert score decline from 5.1 to 0.5, compared with the saline group (4.5 at baseline and 3.5 at 16 weeks). Clinical improvement was maintained at 52-week follow-up.15
Osgood-Schlatter: DPT improves pain relief (SOR B)
In one of the few studies of prolotherapy for adolescents, patients with recalcitrant Osgood-Schlatter disease were randomized to either structured physical therapy or 3 monthly injections of lidocaine, with or without dextrose, over the apophysis and patellar tendon origin.16 Injections began at the most distal point of tenderness and were repeated at 1 cm intervals for a total of 3 to 4 midline injections. The proximal injections were deep to the patellar tendon, on the tibia above the tuberosity.
Pain scores, measured by the Nirschl Pain Phase Scale (0-7), improved significantly more in the DPT group (3.9) compared with either the lidocaine group (2.4) or the exercise group (1.2). Dextrose-treated knees were significantly more likely than knees treated with lidocaine (14 of 21 vs 5 of 22) to be asymptomatic with sport activity. After 3 months, patients in the lidocaine and exercise groups who had not responded adequately were given the option of receiving DPT; those who underwent the 3-month DPT protocol achieved the same level of improvement as the initial DPT group.16
Dextrose injections into the knee can reduce pain and improve a patient’s quality of life.