A walking model to assess the onset of analgesia in osteoarthritis knee pain.

OBJECTIVE: To assess a walking model utilizing a set of standardized treadmill walks to measure acute analgesic response in osteoarthritis (OA) of the knee. DESIGN: Randomized, double-blind, placebo-controlled, multiple dose, three-period crossover study. Patients > or =45 years of age (N=22) with symptomatic knee OA were randomized to naproxen 500 mg bid, tramadol/acetaminophen 37.5 mg/325 mg in forced titration, or placebo in each of three periods. Patients performed multiple 20-minute treadmill walks on Day 1 and Day 3 at a consistent self-selected pace predetermined at screening. Pain intensity (PI) during the walks was assessed on an 11-point numerical rating scale at 0, 3, 6, 9, 12, 15, 18, and 20 min. The primary endpoint was the time-weighted average (TWA) change from baseline PI on Day 3 for the two self-paced walks for the active treatments vs placebo. Time to moderate pain (TTMP) was a key secondary endpoint. RESULTS: Compared with placebo, the TWA change from baseline PI on Day 3 was significantly better with tramadol/acetaminophen (P=0.043) but not with naproxen (P=0.089). TWA change from baseline on Day 1 was also significantly better with both tramadol/acetaminophen (P=0.001) and naproxen (P=0.048) compared with placebo. TTMP was significantly better for tramadol/acetaminophen and naproxen than placebo (P<0.001 to P=0.015) for walks on Day 1 after a single dose and on Day 3. CONCLUSIONS: This novel OA pain model was able to discriminate both tramadol/acetaminophen and naproxen from placebo after single and multiple doses. ClinicalTrials.gov identifier: NCT00772967.

OARSI recommendations for the management of hip and knee osteoarthritis: part III: Changes in evidence following systematic cumulative update of research published through January 2009.

OBJECTIVE: To update evidence for available therapies in the treatment of hip and knee osteoarthritis (OA) and to examine whether research evidence has changed from 31 January 2006 to 31 January 2009. METHODS: A systematic literature search was undertaken using MEDLINE, EMBASE, CINAHL, AMED, Science Citation Index and the Cochrane Library. The quality of studies was assessed. Effect sizes (ESs) and numbers needed to treat were calculated for efficacy. Relative risks, hazard ratios (HRs) or odds ratios were estimated for side effects. Publication bias and heterogeneity were examined. Sensitivity analysis was undertaken to compare the evidence pooled in different years and different qualities. Cumulative meta-analysis was used to examine the stability of evidence. RESULTS: Sixty-four systematic reviews, 266 randomised controlled trials (RCTs) and 21 new economic evaluations (EEs) were published between 2006 and 2009. Of 51 treatment modalities, new data on efficacy have been published for more than half (26/39, 67%) of those for which research evidence was available in 2006. Among non-pharmacological therapies, ES for pain relief was unchanged for self-management, education, exercise and acupuncture. However, with new evidence the ES for pain relief for weight reduction reached statistical significance, increasing from 0.13 [95% confidence interval (CI) -0.12, 0.36] in 2006 to 0.20 (95% CI 0.00, 0.39) in 2009. By contrast, the ES for electromagnetic therapy which was large in 2006 (ES=0.77, 95% CI 0.36, 1.17) was no longer significant (ES=0.16, 95% CI -0.08, 0.39). Among pharmacological therapies, the cumulative evidence for the benefits and harms of oral and topical non-steroidal anti-inflammatory drugs, diacerhein and intra-articular (IA) corticosteroid was not greatly changed. The ES for pain relief with acetaminophen diminished numerically, but not significantly, from 0.21 (0.02, 0.41) to 0.14 (0.05, 0.22) and was no longer significant when analysis was restricted to high quality trials (ES=0.10, 95% CI -0.0, 0.23). New evidence for increased risks of hospitalisation due to perforation, peptic ulceration and bleeding with acetaminophen >3g/day have been published (HR=1.20, 95% CI 1.03, 1.40). ES for pain relief from IA hyaluronic acid, glucosamine sulphate, chondroitin sulphate and avocado soybean unsponifiables also diminished and there was greater heterogeneity of outcomes and more evidence of publication bias. Among surgical treatments further negative RCTs of lavage/debridement were published and the pooled results demonstrated that benefits from this modality of therapy were no greater than those obtained from placebo. CONCLUSION: Publication of a large amount of new research evidence has resulted in changes in the calculated risk-benefit ratio for some treatments for OA. Regular updating of research evidence can help to guide best clinical practice.

Absence of association of asporin polymorphisms and osteoarthritis susceptibility in US Caucasians.

OBJECTIVE: An association between osteoarthritis (OA) and functional polymorphisms in the aspartic acid (d) repeat of the asporin (ASPN) gene was reported in Japanese and Han Chinese populations. The aim of this study was to assess the association of variants in the ASPN gene with the presence of radiographic hand and/or knee OA in a US Caucasian population. METHODS: Ten single nucleotide polymorphisms (SNPs) within the ASPN gene were genotyped in 775 affected siblings with radiographically confirmed hand and/or knee OA, and the allelic, genotypic and haplotypic association results were examined. RESULTS: One variant (SNP RS7033979) showed nominal evidence of association with both hand OA (P=0.042) and knee OA (P=0.032). Four additional SNPs showed nominal evidence of association with knee OA only. These associations were only observed with genotypic tests; the corresponding allelic and haplotype tests did not corroborate the single-point association results. CONCLUSION: These data suggest that polymorphisms within ASPN are not a major influence in susceptibility to hand or knee OA in US Caucasians.

OARSI recommendations for the management of hip and knee osteoarthritis, Part II: OARSI evidence-based, expert consensus guidelines.

PURPOSE: To develop concise, patient-focussed, up to date, evidence-based, expert consensus recommendations for the management of hip and knee osteoarthritis (OA), which are adaptable and designed to assist physicians and allied health care professionals in general and specialist practise throughout the world. METHODS: Sixteen experts from four medical disciplines (primary care, rheumatology, orthopaedics and evidence-based medicine), two continents and six countries (USA, UK, France, Netherlands, Sweden and Canada) formed the guidelines development team. A systematic review of existing guidelines for the management of hip and knee OA published between 1945 and January 2006 was undertaken using the validated appraisal of guidelines research and evaluation (AGREE) instrument. A core set of management modalities was generated based on the agreement between guidelines. Evidence before 2002 was based on a systematic review conducted by European League Against Rheumatism and evidence after 2002 was updated using MEDLINE, EMBASE, CINAHL, AMED, the Cochrane Library and HTA reports. The quality of evidence was evaluated, and where possible, effect size (ES), number needed to treat, relative risk or odds ratio and cost per quality-adjusted life years gained were estimated. Consensus recommendations were produced following a Delphi exercise and the strength of recommendation (SOR) for propositions relating to each modality was determined using a visual analogue scale. RESULTS: Twenty-three treatment guidelines for the management of hip and knee OA were identified from the literature search, including six opinion-based, five evidence-based and 12 based on both expert opinion and research evidence. Twenty out of 51 treatment modalities addressed by these guidelines were universally recommended. ES for pain relief varied from treatment to treatment. Overall there was no statistically significant difference between non-pharmacological therapies [0.25, 95% confidence interval (CI) 0.16, 0.34] and pharmacological therapies (ES=0.39, 95% CI 0.31, 0.47). Following feedback from Osteoarthritis Research International members on the draft guidelines and six Delphi rounds consensus was reached on 25 carefully worded recommendations. Optimal management of patients with OA hip or knee requires a combination of non-pharmacological and pharmacological modalities of therapy. Recommendations cover the use of 12 non-pharmacological modalities: education and self-management, regular telephone contact, referral to a physical therapist, aerobic, muscle strengthening and water-based exercises, weight reduction, walking aids, knee braces, footwear and insoles, thermal modalities, transcutaneous electrical nerve stimulation and acupuncture. Eight recommendations cover pharmacological modalities of treatment including acetaminophen, cyclooxygenase-2 (COX-2) non-selective and selective oral non-steroidal anti-inflammatory drugs (NSAIDs), topical NSAIDs and capsaicin, intra-articular injections of corticosteroids and hyaluronates, glucosamine and/or chondroitin sulphate for symptom relief; glucosamine sulphate, chondroitin sulphate and diacerein for possible structure-modifying effects and the use of opioid analgesics for the treatment of refractory pain. There are recommendations covering five surgical modalities: total joint replacements, unicompartmental knee replacement, osteotomy and joint preserving surgical procedures; joint lavage and arthroscopic debridement in knee OA, and joint fusion as a salvage procedure when joint replacement had failed. Strengths of recommendation and 95% CIs are provided. CONCLUSION: Twenty-five carefully worded recommendations have been generated based on a critical appraisal of existing guidelines, a systematic review of research evidence and the consensus opinions of an international, multidisciplinary group of experts. The recommendations may be adapted for use in different countries or regions according to the availability of treatment modalities and SOR for each modality of therapy. These recommendations will be revised regularly following systematic review of new research evidence as this becomes available.

OARSI recommendations for the management of hip and knee osteoarthritis, part I: critical appraisal of existing treatment guidelines and systematic review of current research evidence.

PURPOSE: As a prelude to developing updated, evidence-based, international consensus recommendations for the management of hip and knee osteoarthritis (OA), the Osteoarthritis Research Society International (OARSI) Treatment Guidelines Committee undertook a critical appraisal of published guidelines and a systematic review (SR) of more recent evidence for relevant therapies. METHODS: Sixteen experts from four medical disciplines (primary care two, rheumatology 11, orthopaedics one and evidence-based medicine two), two continents and six countries (USA, UK, France, Netherlands, Sweden and Canada) formed the guidelines development team. Three additional experts were invited to take part in the critical appraisal of existing guidelines in languages other than English. MEDLINE, EMBASE, Science Citation Index, CINAHL, AMED, Cochrane Library, seven Guidelines Websites and Google were searched systematically to identify guidelines for the management of hip and/or knee OA. Guidelines which met the inclusion/exclusion criteria were assigned to four groups of four appraisers. The quality of the guidelines was assessed using the AGREE (Appraisal of Guidelines for Research and Evaluation) instrument and standardised percent scores (0-100%) for scope, stakeholder involvement, rigour, clarity, applicability and editorial independence, as well as overall quality, were calculated. Treatment modalities addressed and recommended by the guidelines were summarised. Agreement (%) was estimated and the best level of evidence to support each recommendation was extracted. Evidence for each treatment modality was updated from the date of the last SR in January 2002 to January 2006. The quality of evidence was evaluated using the Oxman and Guyatt, and Jadad scales for SRs and randomised controlled trials (RCTs), respectively. Where possible, effect size (ES), number needed to treat, relative risk (RR) or odds ratio and cost per quality-adjusted life year gained (QALY) were estimated. RESULTS: Twenty-three of 1462 guidelines or consensus statements retrieved from the literature search met the inclusion/exclusion criteria. Six were predominantly based on expert opinion, five were primarily evidence based and 12 were based on both. Overall quality scores were 28%, 41% and 51% for opinion-based, evidence-based and hybrid guidelines, respectively (P=0.001). Scores for aspects of quality varied from 18% for applicability to 67% for scope. Thirteen guidelines had been developed for specific care settings including five for primary care (e.g., Prodigy Guidance), three for rheumatology (e.g., European League against Rheumatism recommendations), three for physiotherapy (e.g., Dutch clinical practice guidelines for physical therapy) and two for orthopaedics (e.g., National Institutes of Health consensus guidelines), whereas 10 did not specify the target users (e.g., Ontario guidelines for optimal therapy). Whilst 14 guidelines did not separate hip and knee, eight were specific for knee but only one for hip. Fifty-one different treatment modalities were addressed by these guidelines, but only 20 were universally recommended. Evidence to support these modalities ranged from Ia (meta-analysis/SR of RCTs) to IV (expert opinion). The efficacy of some modalities of therapy was confirmed by the results of RCTs published between January 2002 and 2006. These included exercise (strengthening ES 0.32, 95% confidence interval (CI) 0.23, 0.42, aerobic ES 0.52, 95% CI 0.34, 0.70 and water-based ES 0.25, 95% CI 0.02, 0.47) and nonsteroidal anti-inflammatory drugs (NSAIDs) (ES 0.32, 95% CI 0.24, 0.39). Examples of other treatment modalities where recent trials failed to confirm efficacy included ultrasound (ES 0.06, 95% CI -0.39, 0.52), massage (ES 0.10, 95% CI -0.23, 0.43) and heat/ice therapy (ES 0.69, 95% CI -0.07, 1.45). The updated evidence on adverse effects also varied from treatment to treatment. For example, while the evidence for gastrointestinal (GI) toxicity of non-selective NSAIDs (RR=5.36, 95% CI 1.79, 16.10) and for increased risk of myocardial infarction associated with rofecoxib (RR=2.24, 95% CI 1.24, 4.02) were reinforced, evidence for other potential drug related adverse events such as GI toxicity with acetaminophen or myocardial infarction with celecoxib remained inconclusive. CONCLUSION: Twenty-three guidelines have been developed for the treatment of hip and/or knee OA, based on opinion alone, research evidence or both. Twenty of 51 modalities of therapy are universally recommended by these guidelines. Although this suggests that a core set of recommendations for treatment exists, critical appraisal shows that the overall quality of existing guidelines is sub-optimal, and consensus recommendations are not always supported by the best available evidence. Guidelines of optimal quality are most likely to be achieved by combining research evidence with expert consensus and by paying due attention to issues such as editorial independence, stakeholder involvement and applicability. This review of existing guidelines provides support for the development of new guidelines cognisant of the limitations in existing guidelines. Recommendations should be revised regularly following SR of new research evidence as this becomes available.

Musculoskeletal findings in obese subjects before and after weight loss following bariatric surgery.

OBJECTIVE: To determine the point prevalence of painful musculoskeletal (MSK) conditions in obese subjects before and after weight loss following bariatric surgery. DESIGN: Longitudinal, interventional, unblended. SUBJECTS: Forty-eight obese subjects (47 women, one man, mean age 44+/-9 years; mean body mass index (BMI) 51+/-8 kg/m(2)) recruited from an academic medical center bariatric surgery program. MEASUREMENTS: Comorbid medical conditions; MSK findings; BMI; Western Ontario McMaster Osteoarthritis Index (WOMAC) for pain, stiffness and function; and SF-36 for quality of life. METHODS: Consecutive subjects were recruited from the University Hospitals of Cleveland Bariatric Surgery Program. Musculoskeletal signs and symptoms and non-MSK comorbid conditions were documented at baseline and at follow-up. SUBJECTS completed the SF-36 and the WOMAC questionnaires. Analyses were carried out for each MSK site, fibromyalgia syndrome (FMS) and for the cumulative effect on the spine, upper and lower extremities. The impact of change in comorbid medical conditions, BMI, physical and mental health domains of the SF-36 on the WOMAC pain subscale score was evaluated. SF-36 outcomes were compared to normal published controls. RESULTS: Forty-eight subjects were available for baseline and a follow-up assessment 6-12 months after gastric bypass surgery. They lost an average of 41+/-15 kg and the mean BMI decreased from 51+/-8 to 36+/-7 kg/m(2). Baseline comorbid medical conditions were present in 96% before surgery and 23% after weight loss. There was an increased prevalence of painful MSK conditions at baseline compared to general population frequencies. Musculoskeletal complaints had been present in 100% of obese subjects before, and 23% after weight loss. The greatest improvements occurred in the cervical and lumbar spine, the foot and in FMS (decreased by 90, 83, 83 and 92%, respectively). Seventy-nine percent had upper extremity MSK conditions before and 40% after weight loss. Before surgery, 100% had lower extremity MSK conditions and only 37% did after weight loss. The WOMAC subscale and composite scores all improved significantly, as did the SF-36((R)). Change in BMI was the main factor impacting the WOMAC pain score. CONCLUSION: There was a higher frequency of multiple MSK complaints, including non-weight-bearing sites compared to historical controls, before surgery, which decreased significantly at most sites following weight loss and physical activity. These benefits may improve further, as weight loss may continue for up to 24 months. The benefits seen with weight loss indicate that prevention and treatment of obesity can improve MSK health and function.

An analgesic model for assessment of acute pain response in osteoarthritis of the knee.

BACKGROUND: Osteoarthritis (OA) is frequently treated only during periods of flare, in which rapid onset of analgesia is the outcome target. OBJECTIVE: To assess an acute pain model of knee OA in flare. METHODS: In a multicenter, randomized, double-blind, controlled study, 530 patients aged >or=50 years received valdecoxib 10 mg qd (n=212), rofecoxib 2 5 mg qd (n=208), or placebo (n=110). Pain intensity (PI) was measured on a visual analog scale (VAS) at baseline after a 10-min walk. Patients took their first dose of study medication, rested for 20 min, then measured their PI VAS at 0.5, 1, 1.5, 2, 3, 4, 5, and 6h, each time following a 10-min walk. RESULTS: PI VAS differences (PID) were significantly greater vs placebo both with valdecoxib and rofecoxib (P<0.05) beginning as early as 3h (intent-to-treat population). The percentage of patients with analgesia onset from 4h was significantly higher with both valdecoxib (55%) and rofecoxib (56%) relative to placebo (40%). Median time to first onset of analgesic was shorter with both valdecoxib and rofecoxib compared with placebo (P=0.104 vs valdecoxib; P=0.036 vs rofecoxib). CONCLUSIONS: This acute pain model of knee OA flare detected significant pain relief with agents known to relieve pain in OA and placebo within hours after the first treatment dose, allowing assessment of pain relief within hours rather than days or weeks when evaluating analgesic efficacy in OA. This model is undergoing further study to determine optimal walk times, distances, and rates to maximize its sensitivity.

Hip joint replacement surgery for idiopathic osteoarthritis aggregates in families.

In order to determine whether there is a genetic component to hip or knee joint failure due to idiopathic osteoarthritis (OA), we invited patients (probands) undergoing hip or knee arthroplasty for management of idiopathic OA to provide detailed family histories regarding the prevalence of idiopathic OA requiring joint replacement in their siblings. We also invited their spouses to provide detailed family histories about their siblings to serve as a control group. In the probands, we confirmed the diagnosis of idiopathic OA using American College of Rheumatology criteria. The cohorts included the siblings of 635 probands undergoing total hip replacement, the siblings of 486 probands undergoing total knee replacement, and the siblings of 787 spouses. We compared the prevalence of arthroplasty for idiopathic OA among the siblings of the probands with that among the siblings of the spouses, and we used logistic regression to identify independent risk factors for hip and knee arthroplasty in the siblings. Familial aggregation for hip arthroplasty, but not for knee arthroplasty, was observed after controlling for age and sex, suggesting a genetic contribution to end-stage hip OA but not to end-stage knee OA. We conclude that attempts to identify genes that predispose to idiopathic OA resulting in joint failure are more likely to be successful in patients with hip OA than in those with knee OA.

A newly described hereditary cartilage debonding syndrome.

OBJECTIVE: We describe a hereditary chondropathy characterized by extreme cartilage friability and cartilage-bone debonding, which has not previously been described in the literature. We also describe initial studies into the molecular basis of this disorder. METHODS: Affected family members had multiple shoulder, hip, and knee arthropathies, beginning in the pre-teen years and continuing into adulthood. Various diagnoses had been suggested, including spondyloepiphyseal dysplasia, multiple epiphyseal dysplasia, Legg-Calvé-Perthes disease, and Osgood-Schlatter disease. The affected proband father, his 3 affected children, and unaffected family members provided blood samples, which were examined for single-nucleotide polymorphisms (SNPs) in the chromosome 2 region that included the Frizzled-related protein gene, a soluble Wnt protein signaling antagonist that influences bone and cartilage development. RESULTS: All affected individuals showed clear similarities, including effusions, large loose bodies, and bubbling and delamination of the cartilage with exposure of subchondral bone. All affected individuals exhibited radiographic changes in the hip, showing femoral head flattening and secondary degenerative arthritis, accompanied by abnormalities in the physical properties of the cartilage that were evident upon arthroscopic examination. Two SNPs were identified in subjects with the hereditary cartilage debonding syndrome. Examination of the siblings and parents of the proband demonstrated, however, that both SNPs were present in the unaffected mother and in 2 of 4 unaffected siblings of the proband. CONCLUSION: The clinical findings reported here represent a newly defined clinical syndrome characterized by marked cartilage friability and osteochondral debonding. Because the SNPs are present in the general population, and because unaffected members of this family carry the SNPs, these polymorphisms alone are insufficient to result in the observed phenotype.

The role of anti-inflammatory drugs in the treatment of osteoarthritis: a United States viewpoint.

Guidelines for the treatment of osteoarthritis (OA), first published in 1995 under the auspices of the American College of Rheumatology, were updated with publication of revised recommendations in September 2000 to take account of significant advances in OA management. These advances include increased understanding of the disease process and the introduction of new medications, including the cyclooxygenase-2 (COX-2) selective inhibitors and the intra-articular hyaluronans. In addition, studies demonstrating superior efficacy of non-steroidal anti-inflammatory agents (NSAIDs) vs acetaminophen in the treatment of OA led to a re-evaluation of indications for initial pharmacologic approaches, given the availability of safer NSAIDs. In contrast to the previous recommendation that acetaminophen was the drug of choice for the initial treatment of all patients with OA, the new recommendations support consideration of the use of NSAIDs as initial treatment--either COX-2 selective inhibitors or classical NSAIDs with gastroprotective agents--particularly in patients with moderate to severe pain and inflammation. The important role of non-pharmacologic approaches including weight loss, avoidance of joint overuse, appropriate exercises and orthotics was re-emphasized. It is anticipated that guideline revisions will take place at more frequent intervals in the future, given today's rapid advances in therapeutic approaches, not only for symptomatic therapy but also for therapy targeted to structural disease modification.

Expression profile of protein tyrosine kinase genes in human osteoarthritis chondrocytes.

OBJECTIVE: To determine the expression profile of protein kinase (PK) and protein tyrosine kinase (PTK) genes in human primary osteoarthritis (OA) chondrocytes and to compare it with that of immortalized human chondrocytes T/C 28a4 with a view to learning whether T/C 28a4 cells can be used for elucidating signal transduction pathways in human chondrocytes. DESIGN: We used the Atlas Human cDNA Array and a method based on PCR with degenerate primers to analyse the expression profile of protein kinase genes in primary human OA chondrocytes and compared it with that of immortalized human chondrocyte cell line T/C 28a4 using RT-PCR and Western blotting. RESULTS: A total of 21 PTK genes were identified and several of these have never been shown to be expressed in human OA chondrocytes. Comparative expression analysis of some selected kinase genes showed that the mRNA expression pattern of many protein kinase genes in OA chondrocytes was identical to that of T/C 28a4 cells. However, there were differences in the level of protein expression of selected protein kinases in these cells. For example, mRNA expression of the novel kinase HCK was detected in OA chondrocytes and in the cell lines analysed but by Western blotting HCK protein was not detected in OA chondrocytes. In these studies, we also identified a novel mutant form of the discoidin domain receptor 2 (DDR2) transcript from chondrocyte-like cell line HTB-94. CONCLUSIONS: Our results provide novel information about protein kinase gene expression in OA chondrocytes and indicate that the transformed chondrocyte cell line T/C 28a4 may be suitable for elucidating signal transduction pathways in chondrocytes and to investigate how they regulate chondrocyte function in inflammatory and degenerative joint diseases.

Comparative efficacy and safety of celecoxib and naproxen in the treatment of osteoarthritis of the hip.

Osteoarthritis (OA) is responsible for more disability of the lower extremities in the elderly than any other disease in the US. The pain associated with OA is the primary symptom leading to disability in these patients. Current ACR guidelines recommend consideration of acetaminophen for mild-to-moderate pain and conventional non-steroidal anti-inflammatory drugs (NSAIDs) or COX-2 specific inhibitors for moderate-to-severe OA symptoms. The aim of this study was to compare the efficacy and safety of the COX-1 sparing, COX-2 specific inhibitor, celecoxib, with the conventional NSAID naproxen, and placebo, in the treatment of OA of the hip. In this multicenter, randomized, placebo-controlled trial, 1061 patients with symptomatic OA of the hip were randomized to receive celecoxib at doses of 100 mg, 200 mg, or 400 mg/day; naproxen 1000 mg/day; or placebo, for 12 weeks. Patients were evaluated using standard measures of efficacy at baseline, 2-4 days after discontinuing previous NSAID or analgesic therapy, and after 2, 6, and 12 weeks of treatment. All doses of celecoxib and naproxen significantly improved the symptoms of OA, at all time points compared with placebo. This sustained treatment effect of celecoxib was dose dependent. In terms of pain relief and improvement in functional capacity, celecoxib 200 mg/day and 400 mg/day were similarly efficacious and were comparable to naproxen. Both drugs were generally well tolerated. Celecoxib at a dose of 200 mg/day is as effective as a standard therapeutic dose of the conventional NSAID, naproxen, in reducing the pain associated with OA of the hip.

Hyaluronic acid supplementation.

As evidenced by publication of a new set of guidelines for the treatment of osteoarthritis (OA) by the American College of Rheumatology after only 5 years, modalities available for the management of OA have undergone significant changes. New therapeutic approaches include the use of cyclo-oxygenase-2 inhibitors, and intra-articular hyaluronans (HA). HA, found in a number of body tissues, is altered in the presence of osteoarthritis with decreased molecular weight and concentration resulting in impaired viscoelasticity. Hyaluronan preparations have been shown to decrease pain and increase function in patients with osteoarthritis of the knee. Mechanisms of therapeutic effect include restoration of more normal synovial fluid with improved viscoelasticity, effects on cartilage biosynthesis and degradation, anti-inflammatory effects, and direct analgesic effects. Studies in animal models, and preliminary studies in humans suggest that hyaluronans may have a structure-modifying effect in OA. Hyaluronans represent a substantive addition to the therapeutic armamentarium in osteoarthritis.

Role of collagen hydrolysate in bone and joint disease.

OBJECTIVES: To review the current status of collagen hydrolysate in the treatment of osteoarthritis and osteoporosis. METHODS: Review of past and current literature relative to collagen hydrolysate metabolism, and assessment of clinical investigations of therapeutic trials in osteoarthritis and osteoporosis. RESULTS: Hydrolyzed gelatin products have long been used in pharmaceuticals and foods; these products are generally recognized as safe food products by regulatory agencies. Pharmaceutical-grade collagen hydrolysate (PCH) is obtained by hydrolysis of pharmaceutical gelatin. Clinical studies suggest that the ingestion of 10 g PCH daily reduces pain in patients with osteoarthritis of the knee or hip; blood concentration of hydroxyproline is increased. Clinical use is associated with minimal adverse effects, mainly gastrointestinal, characterized by fullness or unpleasant taste. In a multicenter, randomized, doubleblind, placebo-controlled trial performed in clinics in the United States, United Kingdom, and Germany, results showed no statistically significant differences for the total study group (all sites) for differences of mean pain score for pain. There was, however, a significant treatment advantage of PCH over placebo in German sites. In addition, increased efficacy for PCH as compared to placebo was observed in the overall study population amongst patients with more severe symptomatology at study onset. Preferential accumulation of 14C-labeled gelatin hydrolysate in cartilage as compared with administration of 14C-labeled proline has been reported. This preferential uptake by cartilage suggests that PCH may have a salutary effect on cartilage metabolism. Given the important role for collagen in bone structure, the effect of PCH on bone metabolism in osteoporotic persons has been evaluated. Studies of the effects of calcitonin with and without a collagen hydrolysate-rich diet suggested that calcitonin plus PCH had a greater effect in inhibiting bone collagen breakdown than calcitonin alone, as characterized by a fall in levels of urinary pyridinoline cross-links. PCH appeared to have an additive effect relative to use of calcitonin alone. CONCLUSIONS: Collagen hydrolysate is of interest as a therapeutic agent of potential utility in the treatment of osteoarthritis and osteoporosis. Its high level of safety makes it attractive as an agent for long-term use in these chronic disorders.