Osteoarthritis and beyond: a consensus on the past, present, and future of hyaluronans in orthopedics

Effectiveness of intra-articular injections of sodium bicarbonate and calcium gluconate in the treatment of osteoarthritis of the knee: a randomized double-blind clinical trial

Background

A novel therapeutic management of osteoarthritis (OA) of the knee was assessed. The study aimed to evaluate the effect of monthly sodium bicarbonate with a single (SBCG1) or double dose (SBCG2) of calcium gluconate injections on OA of the knee; as well as the efficacy and safety of both SBCG interventions in the long term.

Methods

A double-blind parallel-group clinical trial with 74 knee OA patients was performed during 12 months, both SBCG interventions were followed-up for another 6mo after intervention. The outcome variables were the Western Ontario-McMaster University Osteoarthritis Index (WOMAC), the Lequesne’s functional index and joint-space width changes from serial radiographs.

Results

After 12 months, group SBCG1 decreased −14.8 (95% CI:-14.2, −17.0) and group SBCG2 decreased −14.6 (−16.9, −12.4) in the global WOMAC score, the mean changes represent 80% and 82% lessened pain, respectively. In the Lequesne Functional Index scale, SBCG1 decreased −11.9 (−10.4, −14.2) and SBCG2 decreased -11.9 (−13.8, −10.0), representing 66 and 69% of improvement. Both mean scores were maintained after intervention discontinued. SBCG2 improved the knees’ joint space width more than SBCG1 at 3 and 18 months. Both SBCG interventions were well tolerated after 12 months of treatment

Conclusion

A solution of sodium bicarbonate and calcium gluconate is effective on reducing the symptoms associated with OA. Its beneficial effect is maintained for one year of continuous monthly administration and at least for 6 months after the administration is discontinued. When the dose of calcium gluconate is increased, it prevents further narrowing of joint-space.

Trial registration

Clinicaltrials.gov NCT00977444 September 11, 2009.

Increased cartilage volume after injection of hyaluronic acid in osteoarthritis knee patients who underwent high tibial osteotomy

PURPOSE

High tibial osteotomy (HTO) is a surgical procedure used to correct abnormal mechanical loading of the knee joint; additionally, intra-articular hyaluronic acid injections have been shown to restore the viscoelastic properties of synovial fluid and balance abnormal biochemical processes. It was hypothesized that combining HTO with intra-articular hyaluronic acid injections would have benefit to improve the cartilage volume of knee joints.

METHODS

Forty patients with medial compartment knee osteoarthritis (OA) were randomly placed into 1 of 2 groups. The study group (n = 20) received 2 cycles (at 6-month intervals) of 5 weekly intra-articular hyaluronic acid injections after HTO operation. The control group (n = 20) did not receive any intra-articular injections after HTO surgery. Cartilage volume (primary outcome) was assessed by magnetic resonance imaging (MRI) pre-operatively and 1 year post-operatively. Treatment efficacy (secondary outcomes) was evaluated with the Western Ontario and McMaster Universities OA Index (WOMAC) and by the comparison of the total rescue medication (paracetamol/diclofenac) used (weeks 6, 12, 24, 48).

RESULTS

MRI studies showed a significant increase in total cartilage volume (p = 0.033), lateral femoral cartilage volume (p = 0.044) and lateral tibial cartilage volume (p = 0.027) in the study group. Cartilage volume loss was detected at the lateral tibial plateau in the control group. There were significant improvements after surgery in both groups for all subscales of WOMAC scores (p < 0.001) compared to the baseline. However, no difference was found between the two groups. The study group had significantly lower amounts of diclofenac consumption (p = 0.017).

CONCLUSION

Based on the findings of the present study, intra-articular hyaluronic acid injections may be beneficial for increasing total cartilage volume and preventing the loss of lateral tibiofemoral joint cartilage after HTO.

LEVEL OF EVIDENCE

Therapeutic study, Level I.

Viscosupplementation treatment of arthritis pain

With the aging of the baby boomer generation, the number of patients with osteoarthritis (OA) is expected to swell, posing treatment challenges. Viscosupplementation, in which hyaluronic acid (HA) is injected into the knee joint, has evolved into an important part of our current therapeutic regimen in addressing the patient with knee pain due to OA. Although suffering from lack of an "evidence-based" approach, and largely funded by industry, there is a growing body of outcome data demonstrating the efficacy of HA in decreasing pain and improving function in patients with knee OA, although no evidence indicates that HA is in any way chondroprotective. The clinical success of HA has led to the ongoing introduction of various forms of HA, although little data are available to justify one over the other.

Hyaluronic acid as a treatment for ankle osteoarthritis

Viscosupplementation refers to the concept of synovial fluid replacement with intra-articular injections of hyaluronic acid (HA) for the relief of pain associated with osteoarthritis (OA). Intra-articular viscosupplementation was approved by the Food and Drug Administration (FDA) in 1997. It is currently indicated only for the treatment of pain associated with knee OA. However, OA can occur in several of the weight-bearing joints of the foot and ankle. Ankle OA produces chronic disability that directly impacts the quality of life. There is only limited published literature relating to the use of HA in the ankle. This paper will review the authors’ experience, indications, clinical outcomes, and complications of viscosupplementation therapy in patients with ankle OA.

Efficacy and Safety of Hyaluronan Treatment in Combination Therapy With Home Exercise for Knee Osteoarthritis Pain

OBJECTIVE

To assess the efficacy and safety of intra-articular injections of sodium hyaluronate combined with a home exercise program (HEP) in the management of pain associated with osteoarthritis (OA) of the knee.

DESIGN

Single-blinded, parallel-design, 1-year clinical study with sequential enrollment.

SETTING

University-based outpatient physiatric practice.

PARTICIPANTS

Sixty patients (18 men, 42 women; age, > or =50 y) with moderate-to-severe pain associated with OA of the knee.

INTERVENTIONS

(1) Five weekly intra-articular hyaluronate injections (5-HYL); (2) 3 weekly intra-articular hyaluronate injections (3-HYL); or (3) a combination of an HEP with 3 weekly intra-articular hyaluronate injections (3-HYL+HEP).

MAIN OUTCOME MEASURES

The primary outcome measure was a 100-mm visual analog scale for pain after a 50-foot walk (15.24 m). Secondary measures included the Western Ontario and McMaster Universities Osteoarthritis Index subscales.

RESULTS

The 3-HYL+HEP group had significantly faster onset of pain relief compared with the 3-HYL (P<.01) and 5-HYL groups (P=.01). All groups showed a mean symptomatic improvement from baseline (reduction in baseline pain at 3 mo was 59%, 49%, and 48% for the 3-HYL+HEP, 3-HYL, and 5-HYL groups, respectively) that was clinically and statistically significant. There were no between-group differences in the incidence or nature of adverse events.

CONCLUSIONS

The combined use of hyaluronate injections with HEP should be considered for management of moderate-to-severe pain in patients with knee OA.

Hyaluronan: pharmaceutical characterization and drug delivery

Hyaluronic acid (HA), is a polyanionic polysaccharide that consists of N-acetyl-D-glucosamine and beta-glucoronic acid. It is most frequently referred to as hyaluronan because it exists in vivo as a polyanion and not in the protonated acid form. HA is distributed widely in vertebrates and presents as a component of the cell coat of many strains of bacteria. Initially the main functions of HA were believed to be mechanical as it has a protective, structure stabilizing and shock-absorbing role in the body. However, more recently the role of HA in the mediation of physiological functions via interaction with binding proteins and cell surface receptors including morphogenesis, regeneration, wound healing, and tumor invasion, as well as in the dynamic regulation of such interactions on cell signaling and behavior has been documented. The unique viscoelastic nature of hyaluronan along with its biocompatibility and nonimmunogenicity has led to its use in a number of cosmetic, medical, and pharmaceutical applications. More recently, HA has been investigated as a drug delivery agent for ophthalmic, nasal, pulmonary, parenteral, and dermal routes. The purpose of our review is to describe the physical, chemical, and biological properties of native HA together with how it can be produced and assayed along with a detailed analysis of its medical and pharmaceutical applications.

Viscosupplementation for the treatment of osteoarthritis of the knee

BACKGROUND

Osteoarthritis (OA) is the most prevalent chronic joint disorder worldwide and is associated with significant pain and disability.

OBJECTIVES

To assess the effects of viscosupplementation in the treatment of OA of the knee. The products were hyaluronan and hylan derivatives (Adant, Arthrum H, Artz (Artzal, Supartz), BioHy (Arthrease, Euflexxa, Nuflexxa), Durolane, Fermathron, Go-On, Hyalgan, Hylan G-F 20 (Synvisc Hylan G-F 20), Hyruan, NRD-101 (Suvenyl), Orthovisc, Ostenil, Replasyn, SLM-10, Suplasyn, Synject and Zeel compositum).

SEARCH STRATEGY

MEDLINE (up to January (week 1) 2006 for update), EMBASE, PREMEDLINE, Current Contents up to July 2003, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched. Specialised journals and reference lists of identified randomised controlled trials (RCTs) and pertinent review articles up to December 2005 were handsearched.

SELECTION CRITERIA

RCTs of viscosupplementation for the treatment of people with a diagnosis of OA of the knee were eligible. Single and double-blinded studies, placebo-based and comparative studies were eligible. At least one of the four OMERACT III core set outcome measures had to be reported (Bellamy 1997).

DATA COLLECTION AND ANALYSIS

Each trial was assessed independently by two reviewers for its methodological quality using a validated tool. All data were extracted by one reviewer and verified by a second reviewer . Continuous outcome measures were analysed as weighted mean differences (WMD) with 95% confidence intervals (CI). However, where different scales were used to measure the same outcome, standardized mean differences (SMD) were used. Dichotomous outcomes were analyzed by relative risk (RR).

MAIN RESULTS

Seventy-six trials with a median quality score of 3 (range 1 to 5) were identified. Follow-up periods varied between day of last injection and eighteen months. Forty trials included comparisons of hyaluronan/hylan and placebo (saline or arthrocentesis), ten trials included comparisons of intra-articular (IA) corticosteroids, six trials included comparisons of nonsteroidal anti-inflammatory drugs (NSAIDs), three trials included comparisons of physical therapy, two trials included comparisons of exercise, two trials included comparisons of arthroscopy, two trials included comparisons of conventional treatment, and fifteen trials included comparisons of other hyaluronans/hylan. The pooled analyses of the effects of viscosupplements against 'placebo' controls generally supported the efficacy of this class of intervention. In these same analyses, differential efficacy effects were observed for different products on different variables and at different timepoints. Of note is the 5 to 13 week post injection period which showed a percent improvement from baseline of 28 to 54% for pain and 9 to 32% for function. In general, comparable efficacy was noted against NSAIDs and longer-term benefits were noted in comparisons against IA corticosteroids. In general, few adverse events were reported in the hyaluronan/hylan trials included in these analyses.

AUTHORS' CONCLUSIONS

Based on the aforementioned analyses, viscosupplementation is an effective treatment for OA of the knee with beneficial effects: on pain, function and patient global assessment; and at different post injection periods but especially at the 5 to 13 week post injection period. It is of note that the magnitude of the clinical effect, as expressed by the WMD and standardised mean difference (SMD) from the RevMan 4.2 output, is different for different products, comparisons, timepoints, variables and trial designs. However, there are few randomised head-to-head comparisons of different viscosupplements and readers should be cautious, therefore, in drawing conclusions regarding the relative value of different products. The clinical effect for some products, against placebo, on some variables at some timepoints is in the moderate to large effect-size range. Readers should refer to relevant tables to review specific detail given the heterogeneity in effects across the product class and some discrepancies observed between the RevMan 4.2 analyses and the original publications. Overall, the analyses performed are positive for the HA class and particularly positive for some products with respect to certain variables and timepoints, such as pain on weight bearing at 5 to 13 weeks postinjection. In general, sample-size restrictions preclude any definitive comment on the safety of the HA class of products; however, within the constraints of the trial designs employed no major safety issues were detected. In some analyses viscosupplements were comparable in efficacy to systemic forms of active intervention, with more local reactions but fewer systemic adverse events. In other analyses HA products had more prolonged effects than IA corticosteroids. Overall, the aforementioned analyses support the use of the HA class of products in the treatment of knee OA.

Hyaluronic acid: a unique topical vehicle for the localized delivery of drugs to the skin

Hyaluronic acid (HA) is a naturally occurring polyanionic, polysaccharide that consists of N-acetyl-D-glucosamine and beta-glucoronic acid. It is present in the intercellular matrix of most vertebrate connective tissues especially skin where it has a protective, structure stabilizing and shock-absorbing role. The unique viscoelastic nature of HA along with its biocompatibility and non-immunogenicity has led to its use in a number of clinical applications, which include: the supplementation of joint fluid in arthritis; as a surgical aid in eye surgery; and to facilitate the healing and regeneration of surgical wounds. More recently, HA has been investigated as a drug delivery agent for various routes of administration, including ophthalmic, nasal, pulmonary, parenteral and topical. In fact, regulatory approval in the USA, Canada and Europe was granted recently for 3% diclofenac in 2.5% HA gel, Solaraze, for the topical treatment of actinic keratoses, which is the third most common skin complaint in the USA. The gel is well tolerated, safe and efficacious and provides an attractive, cost-effective alternative to cryoablation, curettage or dermabrasion, or treatment with 5-fluorouracil. The purpose of this review is to describe briefly the physical, chemical and biological properties of HA together with some details of its medical and pharmaceutical uses with emphasis on this more recent topical application.

Successful nonoperative management of chronic osteoarthritis pain of the knee: safety and efficacy of retreatment with intra-articular hyaluronans

CONTEXT

Although there are many nonsurgical therapies available for the treatment of pain associated with osteoarthritis (OA), their long-term use and safety have not been systematically followed. Intra-articular hyaluronan therapy has been used in the treatment of symptoms associated with OA of the knee with a very favorable safety profile. Five intra-articular hyaluronan products are approved in the US. No systematic review of the safety and efficacy of their chronic use has been reported.

OBJECTIVE

To evaluate the literature on the efficacy and safety of repeat courses of hyaluronan therapy in patients with OA of the knee.

DATA SOURCES

MEDLINE, EMBASE, searched through October 2004.

STUDY SELECTION

Databases were searched using the terms hyaluronan, sodium hyaluronate, hyaluronic acid, hylan, hylan G-F 20, osteoarthritis, adverse events, repeat treatment, and multiple courses.

DATA SYNTHESIS

There are some data that support the benefit and safety of repeat treatment for all products. Data also indicate that one formulation of sodium hyaluronate (molecular weight [MW] 500-730 kDa) is well tolerated and as effective after multiple courses of treatment as it is after a single course. There is also clinical evidence that prolonged use of sodium hyaluronate (MW 500-730 kDa) may significantly decrease the rate of deterioration of joint structure. Localized severe acute inflammatory reactions reported with repeated treatment in some patients are not a class effect but may be linked to physicochemical characteristics of hylan-based treatment.

CONCLUSIONS

Repeat courses of the hyaluronans are safe and effective in the treatment of pain associated with OA of the knee.

Evaluation of hyaluronidase activity in equine and bovine sera and equine synovial fluid samples by use of enzyme zymography

OBJECTIVE

To investigate the activities of hyaluronidases in equine sera and synovial fluid samples and sera from fetal and adult bovids and evaluate the extent to which the degradation of hyaluronan is influenced by chondrocytes.

SAMPLE POPULATION

Commercial and noncommercial samples of equine (n = 6) and bovine (6) sera and 16 synovial fluid samples from horses.

PROCEDURE

Hyaluronidase activities in sera and synovial fluid samples were assessed via enzyme zymography (performed at pH 4, 5, 6, or 7). Chondrocytes were isolated from equine cartilage and cultured with or without hyaluronan (1 mg/mL); the degradation of hyaluronan was assessed via agarose gel electrophoresis.

RESULTS

[corrected] Hyaluronidase activity was detected in equine sera and synovial fluid samples at pH 4, but not at pH 7, and in bovine sera at both pH values. In all samples at pH 4, a major band of activity (molecular weight, approx 60 kd) and some additional higher molecular weight bands were detected; high- and low-molecular-weight activities were detected in bovine sera at pH 7 Hyaluronan in tissue culture medium with or without fetal calf serum was degraded in the presence, but not the absence, of equine chondrocytes.

CONCLUSIONS AND CLINICAL RELEVANCE

Hyaluronidase activity was detected in equine sera and synovial fluid at pH 4 and in bovine sera at pH 4 and 7. Primary chondrocytes in monolayer culture can degrade exogenous hyaluronan. Modulating native hyaluronidase activity may offer a new approach to improve the quantity and quality of hyaluronan in articular joints.

Viscosupplementation for the treatment of osteoarthritis of the knee

BACKGROUND

Osteoarthritis (OA) is the most prevalent chronic joint disorder worldwide and is associated with significant pain and disability.

OBJECTIVES

To assess the effects of viscosupplementation in the treatment of OA of the knee. The products were hyaluronan and hylan derivatives (Adant, Arthrum H, Artz (Artzal, Supartz), BioHy (Arthrease), Durolane, Fermathron, Go-On, Hyalgan, Hylan G-F 20 (Synvisc Hylan G-F 20), NRD-101, Orthovisc, Ostenil, Replasyn, SLM-10, Suplasyn, Synject and Zeel compositum).

SEARCH STRATEGY

MEDLINE, EMBASE, PREMEDLINE, Current Contents up to July 2003, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched. Specialised journals and reference lists of identified randomised controlled trials (RCTs) and pertinent review articles up to April 2004 were handsearched.

SELECTION CRITERIA

RCTs of viscosupplementation for the treatment of people with a diagnosis of OA of the knee were eligible. Single and double-blinded studies, placebo-based and comparative studies were eligible. At least one of the four OMERACT III core set outcome measures had to be reported (Bellamy 1997).

DATA COLLECTION AND ANALYSIS

Each trial was assessed independently by two reviewers (NB, JC) for its methodological quality using a validated tool. All data were extracted by one reviewer (JC) and verified by a second reviewer (VR). Continuous outcome measures were analysed as weighted mean differences (WMD) with 95% confidence intervals (CI). Dichotomous outcomes were analyzed by relative risk (RR).

MAIN RESULTS

Sixty-three trials with a median quality score of 3 (range 1 to 5) were identified. Follow-up periods varied between day of last injection and one year. Thirty-seven trials included comparisons of hyaluronan/hylan and placebo, nine trials included comparisons of intra-articular (IA) corticosteroids, and five trials included comparisons of nonsteroidal anti-inflammatory drugs (NSAIDs). The pooled analyses of the effects of viscosupplements against 'placebo' controls generally supported the efficacy of this class of intervention. In these same analyses, differential efficacy effects were observed for different products on different variables and at different timepoints. Of note is the 5 to 13 week post injection period which showed a percent improvement from baseline of 11 to 54% for pain and 9 to 15% for function. In general, comparable efficacy was noted against NSAIDs and longer-term benefits were noted in comparisons against IA corticosteroids. In general, few adverse events were reported in the hyaluronan/hylan trials included in these analyses.

AUTHORS' CONCLUSIONS

Based on the aforementioned analyses, viscosupplementation is an effective treatment for OA of the knee with beneficial effects: on pain, function and patient global assessment; and at different post injection periods but especially at the 5 to 13 week post injection period. It is of note that based on non-randomised groups, the magnitude of the clinical effect, as expressed by the WMD and standardised mean difference (SMD) from the RevMan 4.1 output, is different for different products, comparisons, timepoints, variables and trial designs. However, there are few randomised head-to-head comparisons of different viscosupplements and readers should be cautious, therefore, in drawing conclusions regarding the relative value of different products. The clinical effect for some products, against placebo, on some variables at some timepoints is in the moderate to large effect-size range. Readers should refer to relevant tables to review specific detail given the heterogeneity in effects across the product class and some discrepancies observed between the RevMan 4.1 analyses and the original publications. Overall, the analyses performed are positive for the HA class and particularly positive for some products with respect to certain variables and timepoints, such as pain on weight bearing at 5 to 13 weeks postinjection. In general, sample-size restrictions preclude any definitive comment on the safety of the HA class of products; however, within the constraints of the trial designs employed no major safety issues were detected. In some analyses viscosupplements were comparable in efficacy to systemic forms of active intervention, with more local reactions but fewer systemic adverse events. In other analyses HA products had more prolonged effects than IA corticosteroids. Overall, the aforementioned analyses support the use of the HA class of products in the treatment of knee OA.

Potential Applications of Hyaluronans in Orthopaedics

The use of hyaluronans for the treatment of pain in patients with osteoarthritis of the knee is well established. There are growing data to suggest that they may also alter the rate of disease progression. Reviewed here are preliminary data that also indicate a potential use for hyaluronans in the treatment of inflammatory arthropathies (e.g. acute joint trauma and fractures) that require long periods of immobilisation, and in tissue engineering for chondral defects. Although the trials that have investigated the use of hyaluronan therapy for the management of traumatic and degenerative musculoskeletal disorders seen in sports medicine have limitations in design and patient number, the results have been promising and suggest that larger controlled clinical trials are warranted.

Non-Animal Stabilized Hyaluronic Acid

Hyaluronic acid (HA) is a major component of human synovial fluid, providing the rheologic properties (elasticity and viscosity) that enable the synovial fluid to perform lubricating and shock-absorbing functions within the healthy joint. Over the last 2 decades, HA preparations have become established in intra-articular therapy of osteoarthritis (OA), particularly OA of the knee. Existing HA preparations, both cross-linked and non-cross-linked, are all administered by courses of multiple injections, and all have been associated with variable success rates. The clinical profile of an HA preparation is inextricably linked to the product's physicochemical properties. For example, the molecular structure of the HA affects the intra-articular residence time, which should in turn influence the duration of action post-injection. Non-animal stabilized hyaluronic acid (NASHA) is a new-generation HA preparation, produced wholly from non-animal sources. NASHA is stabilized using a carefully controlled cross-linking process, which increases the intra-articular residence time from hours to weeks. This facilitates single-injection treatment for OA without affecting the biocompatibility of HA. This review evaluates the properties of NASHA, including the available clinical data, in the context of previously developed HA preparations.