Intraarticular injection of anakinra in osteoarthritis of the knee: A multicenter,randomized, double‐blind,placebo‐controlled study

Objective

To evaluate the clinical response, safety, and tolerability of a single intraarticular injection of anakinra in patients with symptomatic osteoarthritis (OA) of the knee.

Methods

Patients with OA of the knee were enrolled in a multicenter, double‐blind, placebo‐controlled study and randomized 2:1:2 to receive a single intraarticular injection of placebo, anakinra 50 mg, or anakinra 150 mg in their symptomatic knee. Patients were evaluated for 12 weeks postinjection. The primary end point was the change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score from baseline to week 4. Safety assessments included the evaluation of adverse events (AEs), laboratory tests, and vital signs. Pharmacokinetic parameters were assessed in a subset of patients.

Results

Of 170 patients who enrolled, 160 (94%) completed the study. The mean improvements from baseline to week 4 in the WOMAC score were not statistically different between the placebo group and the patients who received 50 mg of anakinra (P = 0.67) or 150 mg of anakinra (P = 0.77). Anakinra was well tolerated. No withdrawals due to AEs or serious AEs, and no serious infections or deaths were reported. No clinically significant trends were noted in laboratory values or vital signs. Pharmacokinetic parameters demonstrated that the mean terminal half‐life of anakinra in serum after intraarticular injection was ∼4 hours.

Conclusion

Anakinra was well tolerated as a single 50‐mg or 150‐mg intraarticular injection in patients with OA of the knee. However, anakinra was not associated with improvements in OA symptoms compared with placebo.

     

Safety and efficacy of long‐term intraarticular steroid injections in osteoarthritis of the knee: A randomized,double‐blind,placebo‐controlled trial

Objective

To evaluate the safety and efficacy of long‐term intraarticular (IA) steroid injections for knee pain related to osteoarthritis (OA).

Methods

In a randomized, double‐blind trial, 68 patients with OA of the knee received IA injections of triamcinolone acetonide 40 mg (34 patients) or saline (34 patients) into the study knee every 3 months for up to 2 years. The primary outcome variable was radiologic progression of joint space narrowing of the injected knee after 2 years. Measurements of minimum joint space width were performed by an automated computerized method on standardized fluoroscopically guided radiographs taken with the patient standing and with the knee in a semiflexed position. The clinical efficacy measure of primary interest was the pain subscale from the Western Ontario and McMaster Universities OA Index (WOMAC). Efficacy measures of secondary interest were the total score on the WOMAC, physician's global assessment, patient's global assessment, patient's assessment of pain, range of motion (ROM) of the affected knee, and 50‐foot walking time. Clinical symptoms were assessed just before each injection.

Results

At the 1‐year and 2‐year followup evaluations, no difference was noted between the two treatment groups with respect to loss of joint space over time. The steroid‐injected knees showed a trend toward greater symptom improvement, especially at 1 year, for the WOMAC pain subscale, night pain, and ROM values (P = 0.05) compared with the saline‐injected knees. Using area under the curve analyses, knee pain and stiffness were significantly improved throughout the 2‐year study by repeated injections of triamcinolone acetonide, but not saline (P < 0.05).

Conclusion

Our findings support the long‐term safety of IA steroid injections for patients with symptomatic knee OA. No deleterious effects of the long‐term administration of IA steroids on the anatomical structure of the knee were noted. Moreover, long‐term treatment of knee OA with repeated steroid injections appears to be clinically effective for the relief of symptoms of the disease.

     

The efficacy and safety of diacerein in the treatment of painful osteoarthritis of the knee: A randomized,multicenter, double‐blind,placebo‐controlled study with primary end points at two months after the end of a three‐month treatment period

Objective

To determine whether the efficacy of diacerein persists at 2 months after the end of a 3‐month treatment period, compared with placebo, in patients with painful knee osteoarthritis (OA).

Methods

After a 1‐week nonsteroidal antiinflammatory drug washout period, patients received either diacerein or placebo for 3 months, followed by an off‐treatment period of 3 months to determine the carryover effects of the drug. Although patients were followed up through month 6, the primary efficacy end point was the percent change from baseline in pain (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC] A) at month 5 (i.e., 2 months after the end of treatment) compared with placebo. The co–primary efficacy end point was the percent change from baseline in the total WOMAC score, also at month 5 versus placebo.

Results

Two hundred three patients were screened, and 168 patients with painful knee OA were randomized. One hundred sixty‐five patients were analyzed in an intent‐to‐treat analysis. At month 5, diacerein showed statistically significant superiority versus placebo as assessed with both the WOMAC A (P < 0.0001) and the total WOMAC (P < 0.0001), demonstrating the carryover effect of the drug. This superiority was already evident from month 2 for pain (P = 0.001) and month 1 for total WOMAC (P = 0.0021). Diacerein was safe and well tolerated. No serious or previously undocumented adverse events were observed during the study.

Conclusion

This is the first published study of a symptomatic slow‐acting OA drug in which the time of assessment of the primary outcome end points was 2 months after the end of a 3‐month treatment period. The results show that diacerein is safe and effective for the treatment of knee OA and has a long carryover effect.

     

Efficacy and safety of four doses of lumiracoxib versus diclofenac in patients with knee or hip primary osteoarthritis: A phase II,four‐week,multicenter, randomized,double‐blind,placebo‐controlled trial

Objective

To compare the efficacy and tolerability of the novel cyclooxygenase 2‐selective inhibitor lumiracoxib with placebo and diclofenac in osteoarthritis (OA).

Methods

Adults (n = 583) with knee or hip OA were randomized to receive for 4 weeks lumiracoxib 50, 100, or 200 mg twice daily or 400 mg once daily; placebo; or diclofenac 75 mg twice daily. Efficacy assessments included overall joint pain intensity and Western Ontario and McMaster Universities Osteoarthritis Index subscales; tolerability was evaluated by adverse event and physician reporting.

Results

All lumiracoxib doses were superior to placebo in relieving pain, improving stiffness, and improving physical function after 4 weeks. At study endpoint, pain relief was comparable among all lumiracoxib dosages and similar to diclofenac. Lumiracoxib tolerability was superior to diclofenac and comparable to placebo.

Conclusion

Lumiracoxib provides predictable and sustained relief from pain, stiffness, and impaired physical function in OA. Lumiracoxib shows clinically comparable efficacy and superior tolerability to diclofenac.

     

Pilot study of the effects of a heat‐retaining knee sleeve on joint pain,stiffness, and function in patients with knee osteoarthritis

Objective

To identify changes in joint pain, stiffness, and functional ability in patients with knee osteoarthritis (OA) after use of a knee sleeve that prevents loss of body heat by the joint.

Methods

Subjects with symptomatic knee OA (n = 52) were randomized to 2 treatment groups: verum sleeve (specially fabricated to retain body heat) or placebo sleeve (standard cotton/elastane sleeve). Subjects wore the sleeve over the more painful OA knee for at least 12 hours daily for 4 weeks. Pain, stiffness, and functional impairment (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]) in the index knee were measured at baseline and after 4 weeks of wear, after which sleeve use was discontinued. Telephone followup interviews were conducted 2 and 4 weeks later.

Results

After 4 weeks of sleeve wear, subjects in the active treatment group reported a 16% decrease in mean WOMAC pain score relative to baseline (P = 0.001). Those who wore the placebo sleeve reported a 9.7% decrease from baseline (P = 0.002). The difference between treatment groups was not statistically significant (P = 0.12). However, it was found that the 12 subjects who believed correctly that they had received the verum sleeve reported a highly significant decrease in WOMAC pain score (?27.5% relative to baseline, P = 0.0001). In comparison, subjects who received the verum sleeve but believed they had received the placebo sleeve exhibited only a marginally significant improvement in pain (?13.0% relative to baseline, P = 0.07). In the placebo group, the modest improvement in pain scores appeared unrelated to the subject's impression of the type of sleeve worn.

Conclusion

This pilot study was insufficiently powered to be a definitive trial of the heat‐retaining sleeve. Given the magnitude of changes in knee pain in the active treatment group, heat retention merits further scientific investigation as a treatment modality for patients with knee OA.

     

The effectiveness of pulsed electrical stimulation in the management of osteoarthritis of the knee: Results of a double‐blind,randomized, placebo‐controlled,repeated‐measures trial

Objective

To determine the effectiveness of subsensory, pulsed electrical stimulation (PES) in the symptomatic management of osteoarthritis (OA) of the knee.

Methods

This was a double‐blind, randomized, placebo‐controlled, repeated‐measures trial in 70 participants with clinical and radiographically diagnosed OA of the knee who were randomized to either PES or placebo. The primary outcome was change in pain score over 26 weeks measured on a 100‐mm visual analog scale (VAS). Other measures included pain on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), function on the WOMAC, patient's global assessment of disease activity (on a 100‐mm VAS), joint stiffness on the WOMAC, quality of life on the Medical Outcomes Study Short‐Form 36 (SF‐36) health survey, physical activity (using the Human Activity Profile and an accelerometer), and global perceived effect (on an 11‐point scale).

Results

Thirty‐four participants were randomized to PES and 36 to placebo. Intent‐to‐treat analysis showed a statistically significant improvement in VAS pain score over 26 weeks in both groups, but no difference between groups (mean change difference 0.9 mm [95% confidence interval −11.7, 13.4]). Similarly, there were no differences between groups for changes in WOMAC pain, function, and stiffness scores (−5.6 [95% confidence interval −14.9, 3.6], −1.9 [95% confidence interval −9.7, 5.9], and 3.7 [95% confidence interval −6.0, 13.5], respectively), SF‐36 physical and mental component summary scores (1.7 [95% confidence interval −1.5, 4.8] and 1.2 [95% confidence interval −2.9, 5.4], respectively), patient's global assessment of disease activity (−2.8 [95% confidence interval −13.9, 8.4]), or activity measures. Fifty‐six percent of the PES‐treated group achieved a clinically relevant 20‐mm improvement in VAS pain score at 26 weeks compared with 44% of controls (12% [95% confidence interval −11%, 33%]).

Conclusion

In this sample of subjects with mild‐to‐moderate symptoms and moderate‐to‐severe radiographic OA of the knee, 26 weeks of PES was no more effective than placebo.

     

Independent association of joint space narrowing and osteophyte formation at the knee with health‐related quality of life in Japan: A cross‐sectional study

Objective

To clarify the individual associations of joint space narrowing (JSN) and osteophytosis at the knee with quality of life (QOL) in Japanese men and women using a large‐scale population‐based cohort from the Research on Osteoarthritis Against Disability (ROAD) study.

Methods

The associations of minimum joint space width (JSW) and osteophyte area in the medial compartment of the knee with QOL parameters, such as the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), were examined. Minimum JSW and osteophyte area in the medial compartment of the knee were measured using a computer‐aided system for the diagnosis of knee osteoarthritis.

Results

Of the 3,040 participants in the ROAD study, the present study included 2,039 participants age 40 years or older who completed the questionnaires (741 men and 1,298 women with a mean ± SD age of 68.6 ± 10.9 years). Multiple regression analysis after adjustment for age and body mass index showed that minimum JSW was significantly associated with scores on the pain domains of the WOMAC in men and women, while osteophyte area was significantly associated with scores on the physical function domains of the WOMAC in men and women.

Conclusion

The findings of this cross‐sectional study using a large‐scale population from the ROAD study indicate that JSN and osteophytosis are independently associated with QOL.

     

The effect of estrogen plus progestin on knee symptoms and related disability in postmenopausal women: The heart and estrogen/progestin replacement study,a randomized,double‐blind,placebo‐controlled trial

Objective

Most observational studies suggest that postmenopausal women taking hormone replacement therapy have a reduced risk of radiographic knee and hip osteoarthritis (OA). There are no randomized trial data on the association of hormone treatment with knee or hip OA, and no studies have been published regarding the relationship of hormone treatment to knee or hip symptoms. This study examined the association of hormone treatment with prevalent knee symptoms and disability related to knee pain as assessed at the final visit of the Heart and Estrogen/Progestin Replacement Study (HERS).

Methods

The HERS was a 4‐year randomized, double‐blind, placebo‐controlled trial of estrogen plus medroxy progesterone acetate for prevention of coronary heart disease in postmenopausal women with documented coronary disease. Participants in this substudy on knee pain were 969 postmenopausal women, with a mean age of 66 years and mean body mass index of 28.6 kg/m², attending the final visit at 9 clinical centers. Frequent knee symptoms were assessed by interview and the severity of knee pain and disability related to knee pain were determined using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Knee symptoms and disability were compared between women assigned to receive hormones and those assigned to receive placebo.

Results

Frequent knee pain was reported in 24.1% of women assigned to receive hormone therapy versus 26.1% of those assigned to the placebo group, a difference of −2.0% (95% confidence interval [95% CI] −7.4% to 3.5%). Among women with knee pain, there were no differences in the severity of pain (score difference −0.2, 95% CI −1.2 to 0.8) or disability (score difference −0.7, 95% CI −3.8 to 2.4) as assessed on the WOMAC. All results were similar for women whose body mass index was either above or below the median.

Conclusion

In a group of older, postmenopausal women with cardiac disease, we found no significant effect of 4 years of estrogen plus progestin therapy compared with placebo on knee pain and related disability. Our findings may not apply to other groups of women or to the effect of hormone therapy on the structural changes of knee OA.

     

Transdermal fentanyl for improvement of pain and functioning in osteoarthritis: A randomized,placebo‐controlled trial

Objective

Although common treatments for osteoarthritis (OA) pain, such as nonsteroidal antiinflammatory drugs (NSAIDs), simple analgesics, and weak opioids, provide relief in some cases, they fail to control pain or are poorly tolerated in many cases. Strong opioids have been used to successfully treat several types of noncancer pain but have rarely been tested in controlled studies. Therefore, we tested the effects of transdermal fentanyl (TDF) in patients with moderate‐to‐severe OA pain, in a placebo‐controlled study.

Methods

The cohort comprised patients with radiologically confirmed OA of the hip or knee (meeting the American College of Rheumatology criteria) requiring joint replacement and with moderate‐to‐severe pain that had been inadequately controlled by weak opioids. The patients were randomized to receive TDF or placebo for 6 weeks after a 1‐week pretreatment run‐in phase. During study treatment, previously prescribed NSAIDs and simple analgesics were continued, but weak opioids were discontinued. All patients had access to paracetamol and metoclopramide. Pain was recorded on a visual analog scale (VAS), and function was assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).

Results

Data were available for 399 patients (202 receiving TDF, 197 receiving placebo), of whom 199 (50%) completed the study. TDF provided significantly better pain relief than placebo, as demonstrated by the primary outcome measure (area under the curve for VAS scores −20 in the TDF group versus −14.6 in the placebo group; P = 0.007). TDF was also associated with significantly better overall WOMAC scores and pain scores. The most common adverse events were nausea, vomiting, and somnolence, and these occurred more often in the TDF group.

Conclusion

TDF can reduce pain and improve function in patients with knee or hip OA.

     

Problems in the development and validation of questionnaire‐based screening instruments for ascertaining cases with symptomatic knee osteoarthritis: The Framingham Study

Objective

To determine if screening for symptomatic knee osteoarthritis (OA) for clinical trials and epidemiologic studies could be satisfactorily done without performing knee radiographs and to develop efficient screening instruments for symptomatic knee OA based on self‐reported symptoms and functional limitations.

Methods

We administered a mailed questionnaire containing many different questions on knee symptoms and functional limitations to 1,921 participants of the Framingham Study who had previously been screened for symptomatic OA with a history and knee radiographs. Recursive partitioning methods (using the Classification and Regression Trees [CART] program) were used to create a set of screening instruments for symptomatic knee OA, which was defined as knee symptoms on most days and radiographic evidence of OA. Three screening instruments were developed to maximize the sensitivity, specificity, and efficiency.

Results

The sensitive instrument had 84% sensitivity and 73% specificity. The specific instrument had 46% sensitivity and 94% specificity. The efficient instrument had 56% sensitivity and 85% specificity. Sensitivity was lower and specificity was higher when these instruments were used to screen for radiographic OA. All instruments had higher sensitivity but lower specificity when used for older subjects (age >60) with greater disease prevalence. However, using any of these instruments as a single‐step screening mechanism resulted in considerable misclassification.

Conclusion

We conclude that none of these instruments has adequate diagnostic test performance to serve as a single‐step evaluation of the presence or absence of symptomatic knee OA.

     

A randomized controlled trial to evaluate the slow‐acting symptom‐modifying effects of colchicine in osteoarthritis of the knee: A preliminary report

Objective

To determine if colchicine added to nimesulide may have a beneficial effect on osteoarthritis (OA) of the knee.

Methods

Colchicine 0.5 mg twice daily or placebo was added to nimesulide (a nonsteroidal antiinflammatory drug) in 36 patients with OA of the knee in a randomized, double‐blind, placebo‐controlled trial over a 5‐month period.

Results

The 30% improvement rate at 20 weeks was higher in the colchicine group than in the control group receiving placebo, as measured by total Western Ontario and McMaster University Osteoarthritis scores (57.9% versus 23.5%) and visual analog scale for index knee pain (52.6% versus 17.6%) (primary measures of response). The significance persisted on combined analysis by Mantel‐Haenszel test (P = 0.062). Comparison of means also showed significant improvement in the colchicine group versus the control group in a multivariate analysis performed using T² test (P = 0.0115).

Conclusion

Among patients with OA of the knee, the group receiving colchicine plus nimesulide exhibited significantly greater symptomatic benefit at 20 weeks than did the control group receiving nimesulide plus placebo.

     

Comparative responsiveness of measures of pain and function after total hip replacement

Objective

To compare the responsiveness of the Functional Assessment System (FAS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Medical Outcomes Study 36‐item Short Form (SF‐36) in patients with osteoarthritis (OA) scheduled for total hip replacement.

Method

Twenty patients with a mean age at surgery of 72.6 years, with primary OA of the hip, were investigated preoperatively and at 3, 6, and 12 months postoperatively with the FAS, WOMAC, and SF‐36. The responsiveness was calculated as standardized response mean, effect size, and relative efficiency.

Results

The pain and function scores of WOMAC and SF‐36 showed greater responsiveness than FAS at 3 months. These differences remained at 6 and 12 months postoperatively. The differences between these 3 outcome measures were found to be similar using several methods for calculating responsiveness.

Conclusion

Self‐administered questionnaires like WOMAC and SF‐36 are more responsive measures of pain and function than range of motion, performance tests, and observer‐administered questions (FAS) following total hip replacement.

     

Steroid injection for osteoarthritis of the hip: A randomized,double‐blind,placebo‐controlled trial

Objective

To determine the efficacy of fluoroscopically guided corticosteroid injection for hip osteoarthritis (OA) in a randomized, double‐blind, placebo‐controlled trial.

Methods

Fifty‐two patients with symptomatic hip OA were randomly allocated to receive placebo (10 mg bipuvicaine, 2 ml saline) (n = 21) or corticosteroid treatment (10 mg bipuvicaine, 40 mg triamcinolone hexacetonide) (n = 31). Patients were followed up for 1, 2, 3, and 6 months. The primary outcome measure was the pain improvement response, defined as a 20% decrease in the Western Ontario and McMaster Universities OA Index (WOMAC) pain score (on 5 100‐mm visual analog scales [VAS]) (WOMAC20) from baseline to 2 months postinjection. Secondary outcomes were a 50% decrease in the WOMAC pain score (WOMAC50), changes in other WOMAC subscale scores, patient's global assessment of health (on a 100‐mm VAS), and Short Form 36 (SF‐36) quality of life indices. Analyses were based on the intent‐to‐treat principle.

Results

The mean WOMAC pain score fell 49.2% (decreasing from 310.1 mm to 157.4 mm) at 2 months postinjection in patients receiving corticosteroid, compared with a decrease of 2.5% (from 314.3 mm to 306.5 mm) in the placebo group (P < 0.0001). The proportion of WOMAC20 responders at 2 months' followup was significantly higher in the corticosteroid group (67.7%) compared with the placebo group (23.8%) (P = 0.004); similar proportions of WOMAC50 responders were observed between groups (61.3% in the corticosteroid group versus 14.3% in the placebo group; P = 0.001). Response differences were maintained at 3 months' followup (58.1% responders in the corticosteroid group versus 9.5% responders in the placebo group; P = 0.004). Significant differences in the WOMAC stiffness and physical function scores (P < 0.0001), patient's global health scores (P = 0.005), and SF‐36 physical component scores (P = 0.04) were observed, with patients in the corticosteroid group showing greater improvements. There were no differences in the frequency of adverse events between groups.

Conclusion

This placebo‐controlled trial confirms that corticosteroid injection can be an effective treatment of pain in hip OA, with benefits lasting up to 3 months in many cases. Future studies should address questions related to the benefits of repeated steroid injection and the effects of this treatment on disease modification.

     

Quality of well‐being in older people with osteoarthritis

Objective

To examine the sensitivity of the Quality of Well‐Being Scale (QWB) as a measure of health‐related quality of life (HRQOL) in people with osteoarthritis (OA).

Methods

The QWB was administered, along with the Arthritis Impact Measurement Scale (AIMS) and other health measures. Health care utilization data were also obtained.

Results

People with OA had a mean QWB score of 0.643. The QWB scores were significantly correlated with total AIMS scores, self‐rated health status, health care costs, depression scores, and most AIMS subscales. In addition, changes in QWB scores after 1 year were significantly correlated with changes in total AIMS scores and some AIMS subscales.

Conclusion

The QWB appears to be a useful and sensitive generic, utility‐based measure of HRQOL in people with OA.

     

Assessing bone loss on radiographs of the knee in osteoarthritis: A cross‐sectional study

Objective

The only established system to grade subchondral bone attrition in knee osteoarthritis (OA) has low interobserver reliability. In this study, our aim was to convert this system into a reliable tool for the assessment of subchondral bone loss in knee OA.

Methods

Templates that were designed to outline the normal contours of the knee were overlaid onto conventional radiographs of a random sample of 100 knees of OA patients who were awaiting total knee replacement (TKR). Seventy‐five films from individuals with chronic knee pain who were not awaiting TKR and 75 films from asymptomatic control subjects were also assessed. Bone loss was graded from 0 (no attrition) to 3 (severe attrition of >10 mm); other established radiologic features were also graded. Spearman's rho was used to determine the correlation of attrition scores with other features, and logistic regression was used to explore whether definite bone attrition was associated with night pain.

Results

The inter‐ and intraobserver reliability values were high for attrition scores and for the presence of definite attrition (score ≥2). Bone attrition was evident in 62% of films from patients awaiting TKR, in 9% of films from individuals with chronic knee pain who were not awaiting TKR, and in 1% of films from controls. In all groups, the correlation between attrition and other features was weak to moderate. There was a nonsignificant association between definite bone attrition and night pain.

Conclusion

Bone attrition is an additional dimension of knee OA that can be measured reliably. Definite attrition may be associated with night pain.

     

Living with osteoarthritis: patient expenditures,health status,and social impact

Objective

To determine “out‐of‐pocket” expenditures related to osteoarthritis (OA) and to explore whether demographic details, health status scores (Medical Outcomes Study 36‐item Short Form [SF‐36] and Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]), or perception of social effect were expenditure determinants.

Methods

A prospective cohort study of community‐dwelling subjects with OA completed 4 consecutive 3‐month cost diaries. In addition, subjects completed the SF‐36 and WOMAC at baseline and at 12 months. Social impact at baseline was collected. Four groups categorized by age and sex were compared. Patients undergoing joint replacement were excluded.

Results

Differences in health status were defined more by age than by sex, especially for physical function. The costs to the patients were high, particularly for women, who spent more on medications and special equipment. Women also reported receiving more assistance from family and friends. Higher disease‐related expenditures were associated with greater pain levels, poorer social function and mental health, and longer duration of disease. Significant independent predictors of total patient expenditures related to OA were being female and having joint stiffness.

Conclusion

Despite having heavily subsidized health care and access to the Pharmaceutical Benefits Scheme, out‐of‐pocket costs for patients with OA in Australia are considerable. Higher expenditures for patients with OA are related to more advanced disease, especially for women.

     

Association of hospital and surgeon procedure volume with patient‐centered outcomes of total knee replacement in a population‐based cohort of patients age 65 years and older

Objective

To study the association between procedure volume and patient‐centered outcomes such as functional status.

Methods

We performed an observational study of a stratified random sample of Medicare beneficiaries who underwent primary total knee replacement (TKR) in 2000. Low‐volume surgeons were defined as surgeons performing ≤6 TKRs per year in the Medicare population, and low‐volume centers were defined as those in which ≤25 TKRs per year were performed. The primary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) functional status score (0–100 scale; 100 = best) 2 years after TKR. We defined a WOMAC functional status score of <60 as a poor functional outcome. Analyses were adjusted for sociodemographic factors, preoperative functional status, and comorbidities.

Results

Fifty‐eight percent of 1,597 eligible patients agreed to participate. Twelve percent of participating patients had a WOMAC score <60 2 years following TKR. Patients operated upon by low‐volume surgeons in low‐volume hospitals were twice as likely to have a poor WOMAC functional status score as patients operated upon by higher volume surgeons and in higher volume hospitals (odds ratio 2.1, 95% confidence interval 1.1–4.2).

Conclusion

Patients operated upon in low‐volume hospitals by low‐volume surgeons had worse functional outcomes 2 years after TKR. These findings add a new and important dimension to the discussion of whether to promote selective referral of procedures such as TKR to high‐volume centers.

     

Risk factors for symptomatic knee osteoarthritis fifteen to twenty‐two years after meniscectomy

Objective

To evaluate the influence of age, sex, body mass index (BMI), extent of meniscal resection, cartilage status, and knee load on the development of radiographically evident osteoarthritis (OA) of the knee and knee symptoms after meniscal resection.

Methods

We evaluated 317 patients with no cruciate ligament injury (mean ± SD age 54 ± 11 years) who had undergone meniscal resection 15–22 years earlier (followup rate 70%), with radiographic and clinical examination. The Knee injury and Osteoarthritis Outcome Score was used to quantify knee‐related symptoms. Sixty‐eight unoperated subjects identified from national population records were included as a reference group.

Results

Symptomatic radiographic OA (corresponding to Kellgren/Lawrence grade ≥2) was present in 83 of 305 operated knees (27%) and 7 of 68 control knees (10%) (relative risk 2.6, 95% confidence interval [95% CI] 1.3–6.1). Patients who had undergone total meniscectomy and subjects with obesity (BMI ≥30) had a greater likelihood of tibiofemoral radiographic OA than those who had undergone partial meniscal resection and those with a BMI <25, respectively. Furthermore, degenerative meniscal tear, intraoperative cartilage changes, and lateral meniscectomy were associated with radiographic OA more frequently than were longitudinal tear, absence of cartilage changes, and medial meniscectomy, respectively. Symptomatic tibiofemoral or patellofemoral radiographic OA was associated with obesity, female sex, and degenerative meniscal tear.

Conclusion

Contributing risk factors for OA development after meniscal resection are similar to risk factors for common knee OA. Systemic factors and local biomechanical factors interact. Obesity, female sex, and preexisting early‐stage OA are features associated with poor self‐reported and radiographic outcome. Partial meniscal resection is associated with less radiographic OA over time than is total meniscectomy.