Effect of therapeutic exercise on knee osteoarthritis after intra-articular injection of botulinum toxin type A, hyaluronate or saline: A randomized controlled trial

The effects of exercise and intra-articular injections versus exercise alone for the treatment of knee osteoarthritis: A scoping review of the evidence

Objective

Current treatment for knee Osteoarthritis (OA) includes exercise and intra-articular injections with corticosteroid (CS), hyaluronic acid (HA), etc., which address OA-related pain and functional limitation. While these interventions can be given together, little is known about the efficacy of a multi-modal approach. The purpose of this scoping review is to examine studies that compare combining exercise and intra-articular knee injections to exercise alone for the management of knee OA.

Methods

A search was performed using PubMed, CINAHL, and Clinicaltrials.gov with MeSH terms "knee osteoarthritis" AND "exercise" AND "injections". Abstracts were screened to meet inclusion criteria of both intervention groups including exercise and one group receiving an injection for treatment of knee OA. Full text articles were screened to meet inclusion criteria and rated using the Pedro Scale.

Results

11 studies that met inclusion criteria. The included studies utilized CS, hyaluronic acid (HA), and Bone Marrow Concentrate (BMC), botulinum toxin A, or a combination of dextrose and lidocaine injections. Most studies included supervised exercise interventions with all studies including strengthening of the quadriceps. CS and exercise compared to exercise alone showed similar improvements in pain. The HA injection studies yielded mixed results with two studies finding HA and exercise was not superior than exercise alone while two other studies found that HA and exercise were superior.

Conclusion

There was a paucity of literature investigating multimodal approaches. Most of the included studies did not find superior effects of adding a knee injection to exercise compared to exercise alone for knee OA.

Botulinum toxin in the rehabilitation of painful syndromes: multiperspective literature analysis, lexical analysis and systematic review of randomized controlled trials

Pain represents a common symptom of several diseases and is often associated with a reduction in rehabilitation outcomes and recovery. The effectiveness of pain alleviation by botulinum toxin has been recently demonstrated. We searched in PubMed the papers about this topic published in the last ten years, and we selected clinical trials, guidelines, meta-analyses, reviews, and systematic reviews. We used different approaches: multiperspective presentation, lexical evaluation, and systematic review. The systematic review was only performed for the randomized controlled trials. We predominantly found reviews and trials about the rehabilitation of stroke/brain injury and epicondylitis. The most common outcome measures were pain, function, and spasticity. Among the common words, pain was the most frequent and the terms were grouped into different families, especially concerning the outcomes. Rehabilitation showed a relatively low frequency. Finally, the systematic review showed moderate-low levels of bias which confirms the effectiveness of botulinum toxin for pain treatment. The current literature about botulinum toxin is wide and globally diffuse but with some limitations in study strategies and clearness in the formal presentation. The evidence justifies the use of botulinum toxin in treating pain in different diseases.

Intraarticular botulinum toxin type A versus corticosteroid or hyaluronic acid for painful knee osteoarthritis: A meta-analysis of head-to-head randomized controlled trials

Intraarticular botulinum toxin type A (BTA) has been shown to be effective for painful knee osteoarthritis (KOA), while the efficacy and safety of intraarticular BTA compared to corticosteroid and hyaluronic acid (HA) remains unknown. A meta-analysis was performed to compare. A search was conducted in Medline (PubMed), CENTER (Cochrane Library), Embase (Ovid), Web of Science, Wanfang, and CNKI to find head-to-head randomized controlled trials (RCTs) directly compare the efficacy and safety between intraarticular BTA and intraarticular corticosteroid or HA for patients with painful KOA. The Cochrane Q test and estimation of I2 were used to assess heterogeneity among studies. After incorporating heterogeneity, a random-effects model was employed for data pooling. Overall, six RCTs involving 348 adults with KOA were included. Intraarticular BTA showed similar efficacy with corticosteroid as evidenced by the changes of pain visual analog scale (VAS: -0.35 [-0.97, 0.28]), total Western Ontario McMaster Universities Arthritis Index (WOMAC: 0.28 [-4.13, 4.69]), and WOMAC for pain (0.64 [-0.42, 1.70]), stiffness (-0.02 [-0.54, 0.50]), and function (0.00 [-2.99, 3.00]). Intraarticular BTA was shown to be more effective than HA in improving pain VAS (-1.31 [-1.97, -0.64]) and WOMAC for pain (-4.81 [-8.73, -0.89]), while the influence on WOMAC for knee stiffness (-1.01 [-4.43, 2.41]) and knee function (-1.86 [-6.71, 2.99]) were similar between groups. No serious adverse events were reported. Evidence from pilot RCTs suggests that intraarticular BTA may confer similar efficacy to corticosteroid for KOA, while BTA may be superior to HA for improving knee pain.

Pain Modulation in Chronic Musculoskeletal Disorders: Botulinum Toxin, a Descriptive Analysis

Botulinum neurotoxin (BoNT), a product of Clostridium botulinum, reversibly inhibits the presynaptic release of the neurotransmitter acetylcholine at the neuromuscular junction. In addition, BoNT blocks the transmission of other substances involved in pain perception and, together with a soft-tissue anti-inflammatory effect, may play a role in analgesia. When first-line treatment fails, second-line therapies might include BoNT. Studies on chronic and recurrent pain using different mechanisms offer heterogenous results that must be validated and standardized. Plantar fasciitis, severe knee osteoarthritis, painful knee and hip arthroplasty, antalgic muscular contractures, and neuropathic and myofascial pain syndromes may benefit from the administration of BoNT. Research on this topic has revealed the main musculoskeletal conditions that can benefit from BoNT, stressing the effects, modalities of administration, doses, and schedule.

What are the unsupervised exercise adherence rates in clinical trials for knee osteoarthritis? A systematic review

BACKGROUND

Exercise is an effective intervention for knee osteoarthritis (OA), and unsupervised exercise programs should be a common adjunct to most treatments. However, it is unknown if current clinical trials are capturing information regarding adherence.

OBJECTIVE

To summarize the extent and quality of reporting of unsupervised exercise adherence in clinical trials for knee OA.

METHODS

Reviewers searched five databases (PubMed, CINAHL, Medline (OVID), EMBASE and Cochrane). Randomized controlled trials where participants with knee OA engaged in an unsupervised exercise program were included. The extent to which exercise adherence was monitored and reported was assessed and findings were subgrouped according to method for tracking adherence. The types of adherence measurement categories were synthesized. A quality assessment was completed using the Physiotherapy Evidence Database (PEDro) scores.

RESULTS

Of 3622 abstracts screened, 176 studies met criteria for inclusion. PEDro scores for study quality ranged from two to ten (mean=6.3). Exercise adherence data was reported in 72 (40.9%) studies. Twenty-six (14.8%) studies only mentioned collection of adherence. Adherence rates ranged from 3.7 to 100% in trials that reported adherence. For 18 studies (10.2%) that tracked acceptable adherence, there was no clear superiority in treatment effect based on adherence rates.

CONCLUSIONS

Clinical trials for knee OA do not consistently collect or report adherence with unsupervised exercise programs. Slightly more than half of the studies reported collecting adherence data while only 40.9% reported findings with substantial heterogeneity in tracking methodology. The clinical relevance of these programs cannot be properly contextualized without this information.

Comparative Efficacy of Intra-Articular Injection, Physical Therapy, and Combined Treatments on Pain, Function, and Sarcopenia Indices in Knee Osteoarthritis: A Network Meta-Analysis of Randomized Controlled Trials

Knee osteoarthritis (KOA) is associated with a high risk of sarcopenia. Both intra-articular injections (IAIs) and physical therapy (PT) exert benefits in KOA. This network meta-analysis (NMA) study aimed to identify comparative efficacy among the combined treatments (IAI+PT) in patients with KOA. Seven electronic databases were systematically searched from inception until January 2023 for randomized controlled trials (RCTs) reporting the effects of IAI+PT vs. IAI or PT alone in patients with KOA. All RCTs which had treatment arms of IAI agents (autologous conditioned serum, botulinum neurotoxin type A, corticosteroids, dextrose prolotherapy (DxTP), hyaluronic acid, mesenchymal stem cells (MSC), ozone, platelet-rich plasma, plasma rich in growth factor, and stromal vascular fraction of adipose tissue) in combination with PT (exercise therapy, physical agent modalities (electrotherapy, shockwave therapy, thermal therapy), and physical activity training) were included in this NMA. A control arm receiving placebo IAI or usual care, without any other IAI or PT, was used as the reference group. The selected RCTs were analyzed through a frequentist method of NMA. The main outcomes included pain, global function (GF), and walking capability (WC). Meta-regression analyses were performed to explore potential moderators of the treatment efficacy. We included 80 RCTs (6934 patients) for analyses. Among the ten identified IAI+PT regimens, DxTP plus PT was the most optimal treatment for pain reduction (standard mean difference (SMD) = -2.54) and global function restoration (SMD = 2.28), whereas MSC plus PT was the most effective for enhancing WC recovery (SMD = 2.54). More severe KOA was associated with greater changes in pain (β = -2.52) and WC (β = 2.16) scores. Combined IAI+PT treatments afford more benefits than do their corresponding monotherapies in patients with KOA; however, treatment efficacy is moderated by disease severity.

The efficacy and safety of intra-articular botulinum toxin type A injection for knee osteoarthritis: A meta-analysis of randomized controlled trials

The purpose of this study was to investigate the efficacy and safety of intra-articular Botulinum Toxin type A (BTA) injection in the management of patients with knee osteoarthritis (KOA). The literature retrieval was conducted based on PRISMA guidelines. Databases including Pubmed, Web of science, EMBASE, and Cochrane Library were searched to identify RCTs that comparing the effects of intra-articular BTA injection with control interventions on patients with KOA. The primary outcomes involved pain and function improvements as well as the occurrence of adverse events. Seven RCTs comprising 548 participants were included in this meta-analysis. Compared with the control group, BTA injection exhibited greater pain reduction at 4 weeks posttreatment (SMD = -0.86, 95% CI [-1.52, -0.19], p = 0.011), but not 8-24 weeks posttreatment (wk 8, SMD = -0.53, 95% CI [-1.21, 0.15], p = 0.127; wk 12, SMD = -0.34, 95% CI [-0.73, 0.04], p = 0.081; wk 24, SMD = -0.65, 95% CI [-1.52, 0.22], p = 0.144). Additionally, no differences were found between BTA injection versus control intervention on functional improvement at all time points assessed (wk 4, WMD = -5.16, 95% CI [-12.31, 2.00], p = 0.158; wk 8, WMD = -0.98, 95% CI [-5.66, 3.71], p = 0.683; wk 12, WMD = -2.52, 95% CI [-7.54, 2.50], p = 0.325); wk 24, WMD = -3.66, 95% CI [-14.09, 6.76], p = 0.491). There was no significant difference in adverse event rate between the BTA and control group (OR = 0.88, 95% CI [0.24, 3.18], p = 0.843). This meta-analysis suggests that intra-articular BTA injection could be an efficious and safe strategy for analgesic treatment of KOA. However, evidence is limited due to the small number and heterogeneity of included studies, this urges further and stronger trials to confirm our findings.

Intra-Articular Injection of Botulinum Toxin for the Treatment of Knee Osteoarthritis: A Systematic Review of Randomized Controlled Trials

The purpose of the present paper was to review the available evidence on intra-articular botulinum toxin (BTX) injection in the treatment of knee osteoarthritis and to compare it to other conservative treatment options. A systematic review of the literature was performed on the PubMed, Scopus, Cochrane Library, Web of Science, Pedro and Research Gate databases with the following inclusion criteria: (1) randomized controlled trials (RCTs), (2) written in the English language, and (3) published on indexed journals in the last 20 years (2001-2021) dealing with the use of BTX intra-articular injection for the treatment of knee OA. The risk of bias was assessed using the Cochrane Risk of Bias tool for RCTs. Nine studies involving 811 patients in total were included. Patients in the control groups received different treatments: conventional physiotherapy, hyaluronic acid injection or prolotherapy or a combination thereof in 5 studies, steroid infiltrative therapy (triamcinolone) in 1 study, placebo in 2, and local anesthetic treatment in 1 study. Looking at the quality of the available literature, two of the included studies reached "Good quality" standard, three were ranked as "Fair", and the rest were considered "Poor". No major complications or serious adverse events were reported following intra-articular BTX, which provided encouraging pain relief, improved motor function, and quality of life. Based on the available data, no clear indication emerged from the comparison of BTX with other established treatments for knee OA. The analysis of the available RCTs on BTX intra-articular injection for the treatment of knee OA revealed modest methodological quality. However, based on the data retrieved, botulinum toxin has been proven to provide good short-term outcomes, especially in patients with pain sensitization, by modulating neurotransmitter release, peripheral nociceptive transduction, and acting on the control of chronic pain from central sensitization.

The application of platelet-rich plasma in the treatment of knee osteoarthritis: A literature review

BACKGROUND

Primary knee osteoarthritis remains a difficult-to-control degenerative disease. With the rise in average life expectancy and the incidence of obesity, osteoarthritis has brought an increasing economic and physical burden on people. This article summarizes the latest understanding of platelet-rich plasma in the treatment of knee osteoarthritis, and reviews the economic issues of PRP.

METHODS

The literatures in Pubmed, Embase, Cochrane library, Web-science and other databases were searched, and literature inclusion and exclusion criteria were formulated. According to the Cochrane systematic reviewer's manual, the included literatures were grouped, and qualitative descriptions and quantitative meta-analysis were performed. Continuous statistical methods were used to compare the effects and adverse effects of PRP before and after treatment, as well as between PRP and other conservative treatments.

RESULTS

A total of 12 randomized controlled trials were included in this study. A total of 959 KOA patients (1070 knees) were enrolled and followed for 3-12 months. PRP total knee scores were significantly better than baseline at 1, 2, 3, 6 and 12 months after treatment (1 month: SMD = 0.60, P < 0.01; 2 months: SMD = 0.98, P < 0.01; 3 months: SMD = 1.16, P < 0.01; 6 months: SMD = 1.49, P < 0.01; 12 months: SMD = 1.47, P < 0.01). In terms of adverse reactions, PRP did not increase the risk of adverse events compared with HA (OR = 0.96, P = 0.85).

CONCLUSIONS

Compared with many other treatment methods, intra-articular injection of PRP has been proven to be safe and effective to improve the quality of life of patients with KOA.

BoNT/A alleviates neuropathic pain in osteoarthritis by down-regulating the expression of P2X4R in spinal microglia

Neuropathic pain in osteoarthritis is one of the reasons why the pain is difficult to treat, and P2X4R plays an important role in neuropathic pain. In addition, BoNT/A has been proven to have analgesic effects on both neuropathic pain and osteoarthritis, but its exact mechanism is still unknown. This study aims to investigate the relationship between the analgesic effect of BoNT/A on osteoarthritis and the expression of P2X4R in spinal cord microglia. The analgesic effect was compared between BoNT/A and compound betamethasone. Western blot analysis was used to examine the expression of P2X4R and BDNF proteins in the spinal cord. Immunohistochemistry was used to determine the cellular location of P2X4R. Mechanical allodynia and weight asymmetry were identified using the hind paw withdrawal threshold and weight bearing test. The results showed that intra-articular injection of MIA induced persistent mechanical allodynia and weight asymmetry in rats. Both BoNT/A and betamethasone could relieve pain behavior in rats, but BoNT/A had a more obvious effect and lasted longer. Furthermore, BoNT/A could reverse the MIA-induced overexpression of BDNF and P2X4R in the spinal dorsal horn. To sum up, BoNT/A is more effective than betamethasone in relieving MIA-induced osteoarthritis pain in rats, and its analgesic effect may be related to the regulation of P2X4R-mediated BDNF release in spinal microglia and the relief of neuropathic pain in osteoarthritis.

Optimal parameters of blood flow restriction and resistance training on quadriceps strength and cross-sectional area and pain in knee osteoarthritis

BACKGROUND: Knee osteoarthritis (KOA) is one of the most common chronic diseases impacting millions of elderly people. OBJECTIVES: The study compared the effects of two intensities of partial blood flow restriction (BFR) with low-intensity resistance training on quadriceps strength and cross-sectional area (CSA), and pain in people with knee osteoarthritis (PwKOA). METHODS: Thirty-five PwKOA, aged 50–65, participated. Quadriceps CSA was measured by ultrasonography, quadriceps strength – by isokinetic dynamometry and pain by VAS. These outcome variables were obtained at the beginning of the study and re-evaluated eight weeks after the intervention. RESULTS: An interaction effect was present for quadriceps CSA (P= 0.042) and quadriceps strength (P= 0.006), showing that using 70% of total occlusion pressure with 30% 1RM had a more significant effect. Knee pain improved significantly through the main effect of BFR (P< 0.001), and low-intensity resistance training (P= 0.011). Pain improved more at 70% of total occlusion pressure, with 30% of 1RM (2.5 ± 1.06) than 50% total occlusion pressure with 10% of 1RM (5.77 ± 1.46). CONCLUSION: A combination of 70% of total occlusion pressure with 30% 1RM could be beneficial in PwKOA in improving pain, and increasing the quadriceps strength. The changes in the quadriceps strength could be a predictor for knee pain.

Therapeutic Effects of Intra-articular Botulinum Neurotoxin Versus Physical Therapy in Knee Osteoarthritis

Background

Knee osteoarthritis (KOA) is the most common cause of chronic knee pain, and disability and different modalities have been used to improve pain and function. Botulinum toxin intra-articular injection is proposed to manage resistant joint pains.

Objectives

This study was carried out to compare therapeutic effects of intra-articular botulinum neurotoxin (BTX) versus physical therapy (PT) in KOA.

Methods

In this single-blind randomized clinical trial, patients with KOA attending to Imam-Reza Hospital, Tehran, Iran, from June 2018 to March 2019 were enrolled. Patients who met the inclusion criteria were randomly divided into BTX receiving a single intra-articular dose of 100 units (250 units from disport brand) and PT groups. The study was described for patients, and informed consent forms were received. For assessment of the pain and related severity, the VAS score and KOOS scales were used. Post-intervention assessment was done 1, 3, and 6 months after the intervention. The level of significance was set at α = 0.05. All data analyses were performed with SPSS version 26 for windows.

Results

In this study, 50 patients were randomly divided into BTX and PT groups. All patients completed the study, and there was no loss to follow-up. There was no significant difference between demographic data of the two groups, including age and BMI. The VAS score was similar in the two groups at the beginning. KOOS subscales were not significantly different, but the quality of life was better in the BTX than the PT group (86.2 ± 15 vs. 72.1 ± 11.5, P < 0.001). One month after the intervention, all KOOS subscales were improved in the BTX group in comparison to the PT group (P < 0.001). This difference was statistically significant in the 3rd (P < 0.001 in all comparisons except Sport/Rec subscale in which P = 0.02) and 6th months (P < 0.001) after the intervention, and the improvement in all KOOS subscales and VAS score were higher in the BTX group than the PT group. The trend of KOOS subscales and VAS score was improved over time in the BTX (P < 0.001 in all tests), but the PT group showed no improvement (P > 0.05) except for Sport/Rec and VAS score (P < 0.001).

Conclusions

Totally, it is concluded that the use of BTX can reduce pain and improve the function and quality of life in patients with KOA.

The Use of Botulinum Toxin A as an Adjunctive Therapy in the Management of Chronic Musculoskeletal Pain: A Systematic Review with Meta-Analysis

Several studies have investigated the effect of botulinum toxin A (BoNT-A) for managing chronic musculoskeletal pain, bringing contrasting results to the forefront. Thus far, however, there has been no synthesis of evidence on the effect of BoNT-A as an adjunctive treatment within a multimodal approach. Hence, Medline via PubMed, EMBASE, and the Cochrane Library-CENTRAL were searched until November 2020 for randomised controlled trials (RCTs) that investigated the use of BoNT-A as an adjunctive therapy for chronic musculoskeletal pain. The risk of bias (RoB) and the overall quality of the studies were assessed through RoB 2.0 and the GRADE approach, respectively. Meta-analysis was conducted to analyse the pooled results of the six included RCTs. Four were at a low RoB, while two were at a high RoB. The meta-analysis showed that BoNT-A as an adjunctive therapy did not significantly decrease pain compared to the sole use of traditional treatment (SDM -0.89; 95% CI -1.91; 0.12; p = 0.08). Caution should be used when interpreting such results, since the studies displayed very high heterogeneity (I = 94%, p < 0.001). The overall certainty of the evidence was very low. The data retrieved from this systematic review do not support the use of BoNT-A as an adjunctive therapy in treating chronic musculoskeletal pain.

Physical therapy, intra-articular dextrose prolotherapy, botulinum neurotoxin, and hyaluronic acid for knee osteoarthritis: randomized clinical trial

This study aimed to compare the efficacy of four treatments in the management of knee osteoarthritis. We carried out a randomized clinical trial with four study arms in an outpatient Department of Physical Medicine and Rehabilitation at a University Hospital. In total, 120 patients with knee osteoarthritis ≥50 years of age were randomly allocated to four groups. The primary outcome was knee pain in visual analog scale and the secondary outcome was the Knee Injury and Osteoarthritis Outcome Score. The exercise was prescribed daily for all participants throughout the study. For physical therapy (group 1), participants received superficial heat, transcutaneous electrical nerve stimulation and pulsed ultrasound. We administered a single intra-articular injection of botulinum neurotoxin type A (group 2) and three injections of hyaluronic acid (group 3) or 20% dextrose (group 4) to patients in the corresponding groups. Mixed analysis of variance showed that there was statistically significant difference between the groups in pain (P < 0.001), and Knee Injury and Osteoarthritis Outcome Score (P < 0.001). Pairwise between- and within-group comparisons showed that botulinum neurotoxin and dextrose prolotherapy were the most, and hyaluronic acid was the least efficient treatments for controlling pain and recovering function in patients. An intra-articular injection of botulinum toxin type A or dextrose prolotherapy is effective first-line treatments. In the next place stands physical therapy particularly if the patient is not willing to continue regular exercise programs. Our study was not very supportive of intra-articular injection of hyaluronic acid as an effective treatment of knee osteoarthritis.

The Effect of Botulinum Toxin Injection into the Common Extensor Tendon in Patients with Chronic Lateral Epicondylitis: A Randomized Trial

BACKGROUND

Botulinum toxin (BTX) is widely used for pain control in various musculoskeletal disorders.

OBJECTIVES

We evaluated the analgesic effect of botulinum toxin type A (BTX-A) in chronic lateral epicondylitis and compared the effect between 10 and 50 IU of BTX-A.

METHODS

Sixty subjects with chronic lateral epicondylitis were included and underwent a BTX-A injection in the common extensor tendon. The subjects were randomly allocated into two groups: the small-dose group (SD group; 30 subjects, 10 IU) and large-dose group (LD group; 30 subjects, 50 IU). Treatment outcomes were evaluated by measuring the pain level using the numeric rating scale (NRS) and measuring grip strength before and one, two, three, four, five, and six months after treatment.

RESULTS

Subjects in both groups showed a significant decrease in NRS scores at all evaluation time points after treatment. The reduction in NRS scores was significantly greater in the LD group at one, two, three, and four months after treatment. Six months after treatment, 19 subjects (63.3%) in the SD group and 21 (70%) in the LD group reported successful pain relief (pain relief ≥50%). The rate of successful pain relief was not significantly different between the two groups. Grip strength was more increased in the LD group at one, two, three, four, and six months after treatment.

CONCLUSIONS

BTX-A injection into the common extensor tendon can be a good treatment option for chronic lateral epicondylitis. The 50-IU BTX-A injection achieved a better outcome than the 10-IU injection.

Lack of standardization among clinical trials of injection therapies for knee osteoarthritis: a systematic review

Purpose: Osteoarthritis (OA) of the knee is a debilitating, expensive, and prevalent disease, and interest in the non-surgical management of knee OA has grown recently. Our objective was to systematically assess the level of heterogeneity among all clinical trials and published studies regarding injections for knee osteoarthritis, in terms of treatment of interest, outcomes evaluated, and time points of outcome assessment. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were utilized to review all published studies and publically available clinical trials from 1 January 2013 to 3 May 2019evaluating intra-articular injections to treat knee OA. Their treatment group and specifics of methodology were scrutinized and compared. Results: 84 published studies and 114 clinical trials were included. Within the 84 published studies, the most common injection treatment studied was hyaluronic acid [N = 22; 26.2%]. In total, 29 different injection treatment groups were utilized. The most common time point for patient evaluation post-injection was 6 months (N = 33 studies; 50.0%), and ranged from 1 week (N = 9 studies; 13.6%) to 7 years (N = 1 study; 1.5%). The most common patient-reported outcome (PRO) measure assessed in the included studies was Western Ontario and McMaster's University Osteoarthritis Index (WOMAC) [N = 44 studies; 66.7%]. For the 114 clinical trials identified, the most common injection treatment studied is platelet-rich plasma in isolation (N = 19; 16.7%). Forty-two different injection treatment types/groups are utilized. The most common PRO measure assessed was WOMAC (N = 77 trials; 67.5%). Overall there were 34 different patient-reported outcome measures used. Conclusions: Research efforts to find the most effective injection therapy for knee OA continue with a tremendous number of injection therapies still being evaluated. Substantial heterogeneity exists in these completed and ongoing trials in terms of patient demographics, OA grades, outcome scores and relatively short-term timing of assessments, with no clear standardization of testing protocol despite proposing to answer the same clinical question. We recommend that studies of this genre going forward be standardized in terms of outcome measures and longer-term follow-up time points, and should incorporate functional assessment evaluations and imaging studies.

Development and Prospect of Intra-Articular Injection in the Treatment of Osteoarthritis: A Review

Osteoarthritis (OA) is a common degenerative disease that affects the vast majority of the elderly and may eventually embark on the road of the total knee arthroplasty (TKA), although controversy still exists in the medical community about the best therapies for osteoarthritis. Compared with physical therapy, oral analgesics and other non-operative treatments, intra-articular injection is more safe and effective. Moreover, intra-articular injection is much less invasive and has fewer adverse reactions than surgical treatment. This article reviews mechanism, benefits and adverse reactions of corticosteroids (CS), hyaluronic acid (HA), platelet-rich plasma (PRP), mesenchymal stem cell (MSCs), stromal vascular fraction (SVF) and other new therapies (for example: gene therapy). The application prospect of intra-articular injection was analyzed according to the recent progress in drug research.

The Use of Botulinum Toxin for the Treatment of Chronic Joint Pain: Clinical and Experimental Evidence

Chronic osteoarthritis pain is an increasing worldwide problem. Treatment for osteoarthritis pain is generally inadequate or fraught with potential toxicities. Botulinum toxins (BoNTs) are potent inhibitors of neuropeptide release. Paralytic toxicity is due to inhibition at the neuromuscular junction, and this effect has been utilized for treatments of painful dystonias. Pain relief following BoNT muscle injection has been noted to be more significant than muscle weakness and hypothesized to occur because of the inhibition of peripheral neuropeptide release and reduction of peripheral sensitization. Because of this observation, BoNT has been studied as an intra-articular (IA) analgesic for chronic joint pain. In clinical trials, BoNT appears to be effective for nociceptive joint pain. No toxicity has been reported. In preclinical models of joint pain, BoNT is similarly effective. Examination of the dorsal root ganglion (DRG) and the central nervous system has shown that catalytically active BoNT is retrogradely transported by neurons and then transcytosed to afferent synapses in the brain. This suggests that pain relief may also be due to the central effects of the drug. In summary, BoNT appears to be safe and effective for the treatment of chronic joint pain. The long-term effects of IA BoNT are still being determined.

The efficacy and safety of Botulinum Toxin Type A in painful knee osteoarthritis: a systematic review and meta-analysis

Objective

A systematic review and meta-analysis was carried out to evaluate the efficacy and safety of Botulinum Toxin Type A in painful knee osteoarthritis.

Methods

The EMBASE and MEDLINE databases were searched to identify randomized controlled trials (RCTs) of Botulinum Toxin Type A in the treatment of painful knee osteoarthritis. The references of included literature were also searched.

Results

Five articles involving 5 RCTs including 314 patients were included in this analysis. There was a significant difference between Botulinum Toxin Type A and placebo in the visual analog scale (VAS) pain scale and Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC) questionnaire score in both the short-term (≤4 weeks) and long-term (≥8 weeks) treatment period. There were no serious adverse events in the Botulinum Toxin Type A groups.

Conclusions

This meta-analysis suggests that Botulinum Toxin Type A is effective and safe in the painful knee OA treatment. However, high-quality randomized controlled studies are still needed to further confirm our findings.

Intra-articular botulinum toxin type A for treatment of knee osteoarthritis: Clinical trial

In recent years, there is a growing interest in new medical applications of botulinum toxin, including pain control, osteoarthritis treatment, and wound healing. While clinical applications of botulinum toxin seem promising, existing evidence regarding the therapeutic effects is still inadequate. The aim was to assess the efficacy of a single injection of abobotulinumtoxin A into the knee joint cavity to reduce pain in elderly people. We carried out a single group clinical trial in a University Hospital. Thirty participants (24 women) more than 50 years of age with knee osteoarthritis were included. Diagnosis of osteoarthritis was based on clinical and radiologic findings. We gave a single injection containing 250 units of Dysport (= 100 units of botulinum neurotoxin type A) diluted with 5 ml of normal saline. The primary outcome measure was knee pain. The secondary outcome was the patients' opinion about their knee and associated problems measured with the Knee injury and Osteoarthritis Outcome Score. The outcomes were measured at the baseline and at 4 weeks after the intervention. Within-group comparisons based on the Knee injury and Osteoarthritis Outcome Scores showed favorable results for joint pain and stiffness, sports, severity of symptoms, quality of life, and daily activities (all p-values < 0.001). Also, pain intensity, joint effusion, knee clicking and locking, and flexion-extension scores showed significant beneficial results (all p-values ≤ 0.005). We concluded that botulinum neurotoxin type A is an effective and safe initial treatment of knee osteoarthritis with clear clinical advantages. Patients' satisfaction, minimum adverse effects in addition to single-dose prescription make the toxin as a choice for the first-line therapy of osteoarthritis at least at the short-term in elderly people. The symptom relief increases the patient's compliance and willing to participate in other therapeutic programs. REGISTRATION: Iranian Registry of Clinical Trials (IRCT) website http://www.irct.ir/, a WHO Primary Register setup, with registration code: Irct ID: IRCT20180416039323N1.