Introduction

Osteoarthritis (OA) is a disease which causes degeneration of joint tissue due to trauma, aging, and metabolic changes. The rising prevalence of knee OA has put an increasingly large physical and financial burden on the U.S. population. Traditional treatment options for OA include lifestyle modifications, pain management, physical therapy, and injections such as hyaluronic acid (HA), corticosteroids, or prolotherapy, with joint replacement as an option for those who have failed conservative measures. More recently, platelet-rich plasma (PRP) injections have started to gain traction in research and clinical practice.  The authors of the review article The Use of Platelet-Rich Plasma in Symptomatic Knee OA summarize the current research and offer suggestions for future studies.

What is PRP and How Does It Work?

PRP is plasma that contains three- to five-times more platelets than whole blood, which typically has 150,000 to 300,000 platelets per microliter. The platelets in PRP contain numerous proteins which are involved in the initiation of healing and growth of new cells. With more proteins in the joint space, the progression of OA may potentially be slowed or halted. PRP is created by taking venous blood from the patient, centrifuging it, and injecting it into the joint space.

PRP vs Control Group

In one double-blind randomized control trial (RCT), 30 patients with knee OA who failed at least 6 weeks of nonoperative treatment received weekly intra-articular injections for either PRP or saline (control group) and were evaluated at one year. The PRP group showed statistically significant improvements in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) functional scale than those in the saline group.

PRP vs HA Injection

There were a few studies which compared PRP injections with HA injections. The first study looked at patients who received either two PRP injections at 4-week intervals or three HA injections at one-week intervals, the standard for this injection. At 12 months, pain scores improved significantly more in the PRP group and only in the PRP group was there improvement on the WOMAC and Study 36-Item Short Form Health Survey (SF-36) functional questionnaires.

A second study reported similar improvements between PRP injection and HA injections at a two-month follow-up but PRP results were better than HA at the 6-month follow up, especially in younger patients, which suggests a longer-term benefit for PRP. When comparing patient age and the degree of OA, the study reported PRP and HA showed similar results in patients over 50 and in those with more advanced OA, suggesting PRP might have better outcomes than HA in younger patients with either cartilage lesions or early OA.

A third double blind randomized control trial compared PRP to HA using the WOMAC, International Knee Documentation Committee (IKDC) for overall function, and Visual Analog Scale (VAS) for pain. No difference was seen between groups in regard to WOMAC score, but there was significant improvement in the IKDC score and VAS score in the PRP group.

PRP vs. Corticosteroid Injection

In a study comparing PRP to corticosteroid injections, PRP provided superior pain and symptom relief for patients with OA as well as significantly improved quality of life when compared to those receiving a cortisone injection.

PRP vs. Prolotherapy

When compared to prolotherapy in a double-blind randomized control trial, PRP injections were more effective in improving WOMAC scores at 1 month, 2 months, and 6 months post-injection.

Limitations

The largest limitations thus far in PRP research is the lack of consistency among PRP processing and concentrations which makes it difficult to prepare an ideal clinical PRP solution. There are still only a few randomized control trials that look at long-term follow-up; more research is needed in this area. The high cost and lack of insurance coverage for PRP injections (out-of-pocket costs range from $500 to $2,000 per injection) limit the number of people who can afford PRP and thus limits the real-world evidence that can be gathered.

Conclusion and PTF Implications

There is clear evidence to support the use of PRP in knee OA. The main advantages of using PRP are its longer-lasting and more efficacious function in restoring articular function when compared with HA injections, corticosteroid injections, and prolotherapy. It appears that PRP is most beneficial for early/low-grade OA compared with more advanced OA. Better outcomes are seen in patient populations under 50 years old with earlier OA due to PRP preventing or slowing the progression of the disease. As research increases on this subject, the use of PRP to treat OA will potentially increase leading to a possible decrease in total joint replacements and financial expenditures associated with OA. A combination of PRP injections and a tailored PT program could prove beneficial for patients with early knee OA and prevent the need for total joint replacement.

Reference

Southworth, T., Naveen, N., Tauro, T., Leong, N., Cole, B. (2019). The Use of Platelet-Rich Plasma in Symptomatic Knee Osteoarthritis. The Journal of Knee Surgery. 32:37-45.

Introduction

Osteoarthritis (OA) is a musculoskeletal condition that commonly affects the knee and/or hip joint(s). There is no cure for OA and most treatment options focus on alleviating pain and preventing functional decline. Hyaluronic acid (HA) and corticosteroids are common intra-articular therapies for OA. If conservative treatments fail, a common procedure for advanced hip or knee OA is a total joint arthroplasty.

Platelet-rich-plasma (PRP) injections are a biologic therapy for treatment of OA receiving increased research interest. PRP is an autologous blood product with a higher concentration of platelets than whole blood which is created by centrifuging it.  PRP is easy to use, minimally-invasive, safe, and does not have as many regulatory requirements as traditional therapeutic pharmaceuticals.

The authors in the article, Platelet-Rick Plasma for the Management of Hip and Knee Osteoarthritis, provide a review of the literature and clinical guidelines regarding the use of PRP as a treatment option for hip and knee OA.

Proposed Biological Mechanisms of PRP in the Context of Osteoarthritis

Osteoarthritis is a disease which causes breakdown of joint tissue including cartilage, bone, ligament, and muscle. The pathophysiology of OA is thought to be caused by an imbalance between anabolic and catabolic mechanisms and is characterized by the presence of increased inflammatory cells.

Although the biology of PRP is not completely understood, it may be able to interfere with the progression of OA by promoting an anabolic response. PRP has been shown to have an initial proinflammatory action followed by a reduction in inflammatory molecules. There is evidence that PRP has analgesic effect as well as a role in inflammation. PRP enhances the joint repair and slows deterioration of tissue.

Effects on Osteoarthritis Symptoms

The first randomized control trial (RCT) on PRP was published in 2012. Fifteen knee OA and three hip OA RCT’s have been published since 2012. The studies are difficult to interpret and methodological concerns include questionable blinding, failure to conceal allocation, selective reporting, small sample sizes and inappropriate statistical analyses. While some studies have shown promise, more rigorous studies need to be performed to determine if PRP is clinically significant.

Three studies compared PRP to a placebo and all reported significant benefits of PRP at 6 or 12 months but small sample sizes limit the influence of the studies. Most studies reported greater improvements in clinical outcomes with PRP over HA for knee OA. These benefits have been seen up until 12 months but appear to decline over time. While results may be statistically significant, there is question about the clinical relevance of the improvements.

Little research attention has been given to comparing PRP to treatments commonly used in the management of OA, such as exercise and analgesics. One small study in knee OA found no difference between PRP and exercise plus transcutaneous electrical nerve stimulation while another trial showed that PRP resulted in better clinical outcomes compared to acetaminophen.

While most studies have evaluated PRP as a monotherapy for OA, PRP could be given in combination with other therapies in clinical practice. It has been postulated that PRP may have an additive effect with HA. In a knee OA study, the combination of PRP and HA led to better pain and function outcomes at one year when compared with HA alone and better function outcomes at three months when compared with PRP alone. Another hip OA trial found that PRP alone was actually more effective than the combination of PRP and HA at two-, six- and 12-months follow-up.

Effects on Joint Structure

One study, reported that nearly 50% of their 13 patients with knee OA showed improved cartilage volume (assessed using ultrasonography) at the lateral and medial femoral condyles, as well as the intercondylar notch, at six months following three PRP injections administered at monthly intervals. Another uncontrolled trial involving 15 patients with no or early knee OA received a single PRP injection. The study found no significant structural worsening at 12-months follow-up (assessed using magnetic resonance imaging) in 73% of those with medial compartment involvement, 80% of those with patellofemoral involvement and 83% of those with lateral compartment involvement. Due to the lack of a control group in both studies, no conclusions can be made at this time about the ability of PRP to slow structural disease progression in those with knee or hip OA.

Clinical Implications

Current clinical guidelines either do not mention or are unable to recommend the use of PRP for the management of OA, based on the lack of high-quality studies and questions regarding statistical significance. Clarity around the efficacy and appropriate protocol for PRP is required before clinical guidelines are likely to be updated.

Overall, the authors of this study recommend that knee OA be managed through education, exercise and, if appropriate, weight loss. If PRP is offered, it is suggested that clinicians inform patients about PRP’s inconclusive evidence so patients can make informed decisions about whether or not to consent to this currently unproven therapy.

Conclusions

Basic science and clinical studies suggest that PRP could be a promising non-operative treatment for OA but more robust studies are needed. Evidence from studies of low to moderate quality show that intra-articular PRP injection therapy is a safe treatment with potential to provide symptomatic benefit for OA up to 12 months, and more effective than HA. While there is some evidence that younger patients and those with less structural change may be more responsive to PRP, further research is needed to establish whether older patients respond effectively to PRP. Effects of PRP on OA structural disease progression are unknown due to lack of studies in this area. No recommendations can currently be made about the optimal PRP protocol for patients with OA.

Physical Therapy First Implications

Physical therapy remains a valuable option for reducing pain and improving function in knee and hip OA while additional research is conducted on alternative treatment options. While the therapists at Physical Therapy First remain up to date on the latest research, it is important to talk with your physician regarding research implications for alternative treatments such as PRP when considering treatment options for knee and hip OA.

Reference

Bennell, K., Hunter, D., Paterson, K. (2017). Platelet-Rich Plasma for the Management of Hip and Knee Osteoarthritis. Complementary and Alternative Medicine, Current Rheumatology Report. 19:24

Introduction

It is theorized that individuals who suffer from migraines are more likely to present with neck pain and cervical muscle dysfunction. There is a lack of information regarding endurance of the neck extensors, the only muscle group with reported weakness in patients with migraine. The authors in the study, Cervical Muscular Endurance Performance in Women with and Without Migraines, looked at cervical muscle endurance of neck flexors and extensors in a population of women most at risk for suffering from migraines.

Methods

Women between the ages of 18 and 55 with a history of migraines were recruited for the study. Study inclusion criteria included a diagnosis of migraine by a neurologist and a frequency of at least three migraine attacks per month for the past three months. Exclusion criteria included presence of a concurrent diagnosis, a history of headache medication overuse, a history of head or neck trauma, current pregnancy, history of cancer, use of recent anesthesia, history of cervical disc disorder, and history of degenerative spine disease. The control group was comprised of women who were age, height, and weight-matched to the study group.

The neck extensor endurance test was performed with patients in a prone position with their head over the end of a plinth and strap support around pelvis and thoracic spine. A separate strap was used to suspend a 2-kg weight approximately 30 cm above the floor. The test ended when the participant was no longer able to sustain the head position, the neck/head position changed more than 5 degrees for three seconds, or the participant opted to terminate the test due to neck pain or fatigue.

The neck flexor endurance test was performed with patients in a hook-lying position with supportive straps at the sternum and pelvis. Patients were asked to perform slight head and neck flexion off the table. The test was concluded when the participant was unable to maintain the unsupported head position or the participant decided to terminate the test due to neck pain or fatigue.

Results

A total of 26 women with migraines and 26 control subjects were included in the study. The migraine group demonstrated a shorter cervical flexor and extensor muscle holding time than the control group. The median hold times for neck flexion were 35.0 seconds and 60.5 seconds for the migraine and control groups, respectively. The median hold times for neck extension were 166.5 seconds and 290.5 seconds for the migraine and control groups, respectively.

Patients in the control group with a history of neck pain showed lower endurance in both flexor and extensor muscle groups. In the migraine group, those with a history of neck pain had lower endurance for the neck extensors but, in contrast, slightly higher endurance for the neck flexors. The proportion of participants who reported neck pain during both endurance tests was similar between the migraine and control groups.

Discussion

The study results suggest that migraines may be associated with reduced neck flexor and extensor cervical muscle endurance. Based on the study findings, it should be considered that the presence of migraines is associated with a lower endurance of the cervical spine musculature; however, the higher prevalence of neck pain reported by those with migraines could have also influenced muscle endurance. When the frequency of neck pain during the test was considered, there were similar rates between those with or without migraine. However, findings of this study along with other recent reports, suggest that decreased cervical muscle performance may be associated with migraines and often coexisting neck pain, particularly for the neck extensors.

Conclusion

Women with migraines had a lower holding time for cervical spine flexor and extensor musculature compared to that of a matched control group. These results suggest that cervical spine muscle endurance may be an important and potentially overlooked aspect of cervical spine muscle function in this population.

Physical Therapy First Implications

This study demonstrates that the endurance of cervical flexors and extensors is important in the evaluation and treatment of patients with migraines and neck pain. Our therapists have the resources to perform these cervical muscular endurance tests and can recommend exercises for strengthening the neck. If you suffer from neck pain or migraines, a tailored home exercise program that includes neck flexor and extensor strengthening created by a skilled physical therapist could be beneficial for decreasing pain and improving function.

Reference

Florencio, L., Oliveira, I., Lodovichi, S., Bragatto, M., Benatto, M., Dach, F…Bevilaqua-Grossi, D (2019). Cervical Muscular Endurance Performance in Women With and Without Migraine. Journal of Orthopaedic and Sports Physical Therapy. Vol 49, No 5, pages 330-336

Introduction

Osteoarthritis (OA) of the knee is a leading cause of disability in the United States. Treatment typically involves symptom management until late stages warrant a knee replacement surgery. Intraarticular glucocorticoid injections are commonly used as a primary treatment for OA but there are conflicting reports on the duration of symptom-relief. Physical therapy (PT) is also a standard treatment, however, referrals for treatment of knee OA have declined between 2007 and 2015, despite guideline recommendations. In the U.S. Military Health System, patients who were initially diagnosed with knee OA were more likely to be referred for glucocorticoid injection than for physical therapy (51% vs. 29%), and only 13% received both. The authors in the article, Physical Therapy versus Glucocorticoid Injection for Osteoarthritis of the Knee, performed a randomized control trial comparing the long-term functional outcomes of patients who receive either physical therapy or a glucocorticoid injection for the treatment of knee OA.

Methods

Patients were either beneficiaries of the Military Healthy System (active-duty or retired service members) or their family members. Patients were eligible for the study if they were clinically diagnosed with OA and radiographs showed Grade I-IV arthritis of the knee joint. Patients were randomly assigned to either the PT group or the glucocorticoid injection group.

The injection group received one ml of triamcinolone acetonide and seven ml of 1% lidocaine and could receive up to three total injections in the 1-year trial period, as needed. This group had re-assessments performed at 4-months and 9-months. Patients in the PT group underwent eight sessions of PT over the initial 4-6-week period which included patient education, a written home exercise program, manual therapy, stretching and exercise. PT group patients could also attend an additional 1-3 sessions at the 4-month and 9-month reassessments as needed. All five treating therapists were board certified in orthopedic PT and fellowship-trained in orthopedic manual therapy.

The researchers assessed outcome measures at baseline and at one-year post-intervention physical function using the WOMAC and GROC questionnaires, and two functional tests which included the Timed Up and Go test and the Alternate Step Test.

Results

A total of 156 patients were recruited for the study; 78 patients in each treatment group. The mean treatment-related costs for all knee-related medical care during the one-year trial period was similar in the two groups ($2,113 in the glucocorticoid injection group and $2,131 in the physical therapy group). The mean (±SD) WOMAC scores at 1 year were 55.8±53.8 in the glucocorticoid injection group and 37.0±30.7 in the PT group. At one year, the median score on the Global Rating of Change scale was +5 (“quite a bit better”) in the physical therapy group and +4 (“moderately better”) in the glucocorticoid injection group. Patients in the PT group performed better (lower mean times) on both functional tests than patients in the glucocorticoid injection group.

Conclusion

In conclusion, physical therapy for OA of the knee resulted in better absolute scores on the WOMAC and GROC scales and the Timed Up and Go and Alternate Step functional tests than glucocorticoid injection at one year.

Physical Therapy First Implications

The therapists at Physical Therapy First are board-certified orthopedic clinical specialists and are residency or fellowship-trained in manual therapy. If you are having knee pain and/or have been diagnosed with knee OA, PT treatment may improve your pain and long-term function.

Reference:

Deyle, G., Allen, C., Allison, S., Gill, N., Hando, B., Petersen, E…Rhon, D (2020). Physical Therapy versus Glucocorticoid Injection for Osteoarthritis of the Knee. The New England Journal of Medicine. 382,15, pages 1420-1429.