Piran Aliabadi

Incidental meniscal findings on knee MRI in middle-aged and elderly persons.

BACKGROUND Magnetic resonance imaging (MRI) of the knee is often performed in patients who have knee symptoms of unclear cause. When meniscal tears are found, it is commonly assumed that the symptoms are attributable to them. However, there is a paucity of data regarding the prevalence of meniscal damage in the general population and the association of meniscal tears with knee symptoms and with radiographic evidence of osteoarthritis. METHODS We studied persons from Framingham, Massachusetts, who were drawn from census-tract data and random-digit telephone dialing. Subjects were 50 to 90 years of age and ambulatory; selection was not made on the basis of knee or other joint problems. We assessed the integrity of the menisci in the right knee on 1.5-tesla MRI scans obtained from 991 subjects (57% of whom were women). Symptoms involving the right knee were evaluated by questionnaire. RESULTS The prevalence of a meniscal tear or of meniscal destruction in the right knee as detected on MRI ranged from 19% (95% confidence interval [CI], 15 to 24) among women 50 to 59 years of age to 56% (95% CI, 46 to 66) among men 70 to 90 years of age; prevalences were not materially lower when subjects who had had previous knee surgery were excluded. Among persons with radiographic evidence of osteoarthritis (Kellgren-Lawrence grade 2 or higher, on a scale of 0 to 4, with higher numbers indicating more definite signs of osteoarthritis), the prevalence of a meniscal tear was 63% among those with knee pain, aching, or stiffness on most days and 60% among those without these symptoms. The corresponding prevalences among persons without radiographic evidence of osteoarthritis were 32% and 23%. Sixty-one percent of the subjects who had meniscal tears in their knees had not had any pain, aching, or stiffness during the previous month. CONCLUSIONS Incidental meniscal findings on MRI of the knee are common in the general population and increase with increasing age.

Comparison of the prevalence of knee osteoarthritis between the elderly Chinese population in Beijing and whites in the United States: The Beijing Osteoarthritis Study.

OBJECTIVE To estimate the prevalence of radiographic and symptomatic knee osteoarthritis (OA) in a population-based sample of elderly subjects in Beijing, China and compare it with that reported in the Framingham (Massachusetts) OA Study. METHODS We recruited a sample of persons age > or = 60, using door-to-door enumeration in randomly selected neighborhoods in Beijing. Subjects completed a home interview including questions on knee symptoms and a hospital examination including knee radiographs obtained during weight bearing. The protocol was identical to that used in the Framingham OA Study. A reader read intermingled Beijing and Framingham Study films to ensure high reliability. We defined a subject as having radiographic knee OA when the Kellgren/Lawrence grade was > or = 2 in at least 1 knee. Symptomatic knee OA was recorded as present when knee pain was reported and the symptomatic knee had radiographic OA. We estimated the prevalence of these entities in elderly subjects in Beijing and compared it with OA prevalence in Framingham, using an age-standardized prevalence ratio. RESULTS Of 2,180 age-eligible Beijing subjects contacted, knee radiographs were obtained in 1,787 (82.0%). The prevalence of radiographic knee OA was 42.8% in women and 21.5% in men. Symptomatic knee OA occurred in 15.0% of women and 5.6% of men. Compared with women of the same age in Framingham, women in Beijing had a higher prevalence of radiographic knee OA (prevalence ratio 1.45, 95% confidence interval 1.31-1.60) and of symptomatic knee OA (prevalence ratio 1.43, 95% confidence interval 1.16-1.75). The prevalence of knee OA in Chinese men was similar to that in their white US counterparts (for radiographic OA, prevalence ratio 0.90; for symptomatic OA, prevalence ratio 1.02). CONCLUSION Using identical methods and definitions to evaluate the prevalence of OA across populations, we found, surprisingly, that older Chinese women have a higher prevalence of knee OA than women in Framingham, Massachusetts. The prevalence in men was comparable. Possible explanations for these differences range from genetic differences to heavy physical activity among Chinese.

Association between radiographic features of knee osteoarthritis and pain: results from two cohort studies

Objective To examine the relation of radiographic features of osteoarthritis to knee pain in people with knees discordant for knee pain in two cohorts. Design Within person, knee matched, case-control study. Setting and participants Participants in the Multicenter Osteoarthritis (MOST) and Framingham Osteoarthritis studies who had knee radiographs and assessments of knee pain. Main outcome measures Association of each pain measure (frequency, consistency, and severity) with radiographic osteoarthritis, as assessed by Kellgren and Lawrence grade (0-4) and osteophyte and joint space narrowing grades (0-3) among matched sets of two knees within individual participants whose knees were discordant for pain status. Results 696 people from MOST and 336 people from Framingham were included. Kellgren and Lawrence grades were strongly associated with frequent knee pain—for example, for Kellgren and Lawrence grade 4 v grade 0 the odds ratio for pain was 151 (95% confidence interval 43 to 526) in MOST and 73 (16 to 331) in Framingham (both P<0.001 for trend). Similar results were also seen for the relation of Kellgren and Lawrence scores to consistency and severity of knee pain. Joint space narrowing was more strongly associated with each pain measure than were osteophytes. Conclusions Using a method that minimises between person confounding, this study found that radiographic osteoarthritis and individual radiographic features of osteoarthritis were strongly associated with knee pain.

Meniscal tear in knees without surgery and the development of radiographic osteoarthritis among middle-aged and elderly persons: The Multicenter Osteoarthritis Study.

OBJECTIVE Although partial meniscectomy is a risk factor for the development of knee osteoarthritis (OA), there is a lack of evidence that meniscal damage that is not treated with surgery would also lead to OA, suggesting that surgery itself may cause joint damage. Furthermore, meniscal damage is common. The aim of this study was to evaluate the association between meniscal damage in knees without surgery and the development of radiographic tibiofemoral OA. METHODS We conducted a prospective case-control study nested within the observational Multicenter Osteoarthritis Study, which included a sample of men and women ages 50-79 years at high risk of knee OA who were recruited from the community. Patients who had no baseline radiographic knee OA but in whom tibiofemoral OA developed during the 30-month followup period were cases (n = 121). Control subjects (n = 294) were drawn randomly from the same source population as cases but had no knee OA after 30 months of followup. Individuals whose knees had previously undergone surgery were excluded. Meniscal damage was defined as the presence of any medial or lateral meniscal tearing, maceration, or destruction. RESULTS Meniscal damage at baseline was more common in case knees than in control knees (54% versus 18%; P < 0.001). The model comparing any meniscal damage with no meniscal damage (adjusted for baseline age, sex, body mass index, physical activity, and mechanical knee alignment) yielded an odds ratio of 5.7 (95% confidence interval 3.4-9.4). CONCLUSION In knees without surgery, meniscal damage is a potent risk factor for the development of radiographic OA. These results highlight the need for better understanding, prevention, and treatment of meniscal damage.

Prevalence of abnormalities in knees detected by MRI in adults without knee osteoarthritis: population based observational study (Framingham Osteoarthritis Study)

Objective To examine use of magnetic resonance imaging (MRI) of knees with no radiographic evidence of osteoarthritis to determine the prevalence of structural lesions associated with osteoarthritis and their relation to age, sex, and obesity. Design Population based observational study. Setting Community cohort in Framingham, MA, United States (Framingham osteoarthritis study). Participants 710 people aged >50 who had no radiographic evidence of knee osteoarthritis (Kellgren-Lawrence grade 0) and who underwent MRI of the knee. Main outcome measures Prevalence of MRI findings that are suggestive of knee osteoarthritis (osteophytes, cartilage damage, bone marrow lesions, subchondral cysts, meniscal lesions, synovitis, attrition, and ligamentous lesions) in all participants and after stratification by age, sex, body mass index (BMI), and the presence or absence of knee pain. Pain was assessed by three different questions and also by WOMAC questionnaire. Results Of the 710 participants, 393 (55%) were women, 660 (93%) were white, and 206 (29%) had knee pain in the past month. The mean age was 62.3 years and mean BMI was 27.9. Prevalence of “any abnormality” was 89% (631/710) overall. Osteophytes were the most common abnormality among all participants (74%, 524/710), followed by cartilage damage (69%, 492/710) and bone marrow lesions (52%, 371/710). The higher the age, the higher the prevalence of all types of abnormalities detectable by MRI. There were no significant differences in the prevalence of any of the features between BMI groups. The prevalence of at least one type of pathology (“any abnormality”) was high in both painful (90-97%, depending on pain definition) and painless (86-88%) knees. Conclusions MRI shows lesions in the tibiofemoral joint in most middle aged and elderly people in whom knee radiographs do not show any features of osteoarthritis, regardless of pain.

Is Obesity a Risk Factor for Progressive Radiographic Knee Osteoarthritis

OBJECTIVE To examine whether obesity increases the risk of progression of knee osteoarthritis (OA). METHODS We used data from the Multicenter Osteoarthritis Study, a longitudinal study of persons with or at high risk of knee OA. OA was characterized at baseline and 30 months using posteroanterior fixed-flexion radiographs and Kellgren/Lawrence (K/L) grading, with alignment assessed on full-extremity films. In knees with OA at baseline (K/L grade 2 or 3), progression was defined as tibiofemoral joint space narrowing on the 30-month radiograph. In knees without OA at baseline (K/L grade 0 or 1), incident OA was defined as the development of radiographic OA at 30 months. Body mass index (BMI) at baseline was classified as normal (<25 kg/m(2)), overweight (25-<30 kg/m(2)), obese (30-<35 kg/m(2)), and very obese (>or=35 kg/m(2)). The risk of progression was tested in all knees and in subgroups categorized according to alignment. Analyses were adjusted for age, sex, knee injury, and bone density. RESULTS Among the 2,623 subjects (5,159 knees), 60% were women, and the mean +/- SD age was 62.4 +/- 8.0 years. More than 80% of subjects were overweight or obese. At baseline, 36.4% of knees had tibiofemoral OA, and of those, only one-third were neutrally aligned. Compared with subjects with a normal BMI, those who were obese or very obese were at an increased risk of incident OA (relative risk 2.4 and 3.2, respectively [P for trend < 0.001]); this risk extended to knees from all alignment groups. Among knees with OA at baseline, there was no overall association between a high BMI and the risk of OA progression; however, an increased risk of progression was observed among knees with neutral but not varus alignment. The effect of obesity was intermediate in those with valgus alignment. CONCLUSION Although obesity was a risk factor for incident knee OA, we observed no overall relationship between obesity and the progression of knee OA. Obesity was not associated with OA progression in knees with varus alignment; however, it did increase the risk of progression in knees with neutral or valgus alignment. Therefore, weight loss may not be effective in preventing progression of structural damage in OA knees with varus alignment.

Prevalence, incidence and progression of hand osteoarthritis in the general population: the Framingham Osteoarthritis Study

Objectives To describe the prevalence and longitudinal course of radiographic, erosive and symptomatic hand osteoarthritis (HOA) in the general population. Methods Framingham osteoarthritis (OA) study participants obtained bilateral hand radiographs at baseline and 9-year follow-up. The authors defined radiographic HOA at joint level as Kellgren–Lawrence grade (KLG)≥2, erosive HOA as KLG≥2 plus erosion and symptomatic HOA as KLG≥2 plus pain/aching/stiffness. Presence of HOA at individual level was defined as ≥1 affected joint. The prevalence was age-standardised (US 2000 Population 40–84 years). Results Mean (SD) baseline age was 58.9 (9.9) years (56.5% women). The age-standardised prevalence of HOA was only modestly higher in women (44.2%) than men (37.7%), whereas the age-standardised prevalence of erosive and symptomatic OA was much higher in women (9.9% vs 3.3%, and 15.9% vs 8.2%). The crude incidence of HOA over 9-year follow-up was similar in women (34.6%) and men (33.7%), whereas the majority of those women (96.4%) and men (91.4%) with HOA at baseline showed progression during follow-up. Incident metacarpophalangeal and wrist OA were rare, but occurred more frequently and from an earlier age in men than women. Development of erosive disease occurred mainly in those with non-erosive HOA at baseline (as opposed to those without HOA), and was more frequent in women (17.3%) than men (9.6%). Conclusions The usual female predominance of prevalent and incident HOA was less clear for radiographic HOA than for symptomatic and erosive HOA. With an ageing population, the impact of HOA will further increase.

Knee buckling : Prevalence, risk factors, and associated limitations in function

Context Knee buckling is the sudden loss of postural support across the knee at a time of weight bearing. Its prevalence and consequences are not clear. Contribution This study of 2351 community-dwelling, middle-age and older adults found that 278 participants (12%) reported at least 1 episode of knee buckling in the past 3 months. Of these, 13% fell during the episode. Knee pain, quadriceps weakness, and worse physical function were associated with buckling. Caution The studys cross-sectional design limits causal inferences. Implications Knee buckling occurs commonly among middle-age and older adults and is sometimes associated with functional limitations. The Editors Knee buckling is the sudden loss of postural support across the knee at a time of weight bearing. Affected persons often characterize this phenomenon as giving way. One study has suggested that the prevalence of knee buckling is high in selected persons seeking physical therapy and stability training for knee osteoarthritis (1). However, the prevalence of knee buckling in the community and its effect on physical function have not been described. Buckling occurs mostly in persons with knee pain, and frequent knee pain affects about 25% of adults (2). Many of these persons have osteoarthritis of the knee (3). Whereas buckling and instability are a focus of orthopedic literature, these phenomena are neglected in medicine textbooks in chapters on knee pain or osteoarthritis (4, 5). When buckling is discussed, it is identified as evidence of an internal derangement, such as an anterior cruciate ligament (ACL) tear (5). A search of MEDLINE for articles on knee instability (subject), buckling, or giving way (words in title or abstract) from 1966 through June 2007 revealed that articles on knee buckling or instability were found almost exclusively in the orthopedic literature, where it was noted as a complication of surgery (6, 7); a hallmark symptom of ACL tear (8); or a consequence of specific, uncommon conditions, such as patellar dislocation (9). Thus, buckling is not generally described in native, uninjured knees. Buckling and symptoms of impending falling may be treatable or at least prevented, but avoiding activities that precipitate buckling may limit function. Buckling may cause falls and fractures and may help to explain the increased risk for hip fracture in patients with osteoarthritis who have higher bone density than others their age and who, therefore, should be at diminished risk for fracture (10). We sought to characterize the frequency of knee buckling in the previous 3 months among persons from the community. We also evaluated whether buckling was associated with particular characteristics, such as knee or other joint pain or muscular weakness. Finally, we examined the relationship of buckling with physical function and determined whether, independent of knee pain, buckling was associated with limited function. Methods Participants Our study cohort consisted of members of the Framingham Offspring Study and a newly recruited cohort from Framingham, Massachusetts. We combined these participants into a single cohort that we designated the Framingham Osteoarthritis Study cohort. Participants were examined between 2002 to 2005. Participants in the Framingham Offspring Study included surviving descendants and spouses of descendants of participants in the original Framingham Heart Study. The Framingham Osteoarthritis Study is a population-based study of osteoarthritis. As part of a study of the inheritance of osteoarthritis, descendants of the original Framingham Heart Study cohort (the descendants of the original cohort and their spouses constitute the Framingham Offspring) whom we had studied for knee or hand osteoarthritis in earlier Framingham Osteoarthritis studies (11) were selected. This allowed us to examine inheritance patterns of osteoarthritis and genetic linkage. Selected Framingham Offspring were originally examined from 1992 to 1995 (11). All surviving members of this group and those not lost to follow-up were contacted by a letter of invitation, and those interested in participating received a follow-up telephone call to schedule clinic examinations (Appendix Figure 1). Appendix Figure 1. Study flow diagram: the Framingham Offspring Study cohort. ACL = anterior cruciate ligament; MRI = magnetic resonance imaging. The newly recruited participants to the Framingham Osteoarthritis Study were drawn from a random sample of the Framingham, Massachusetts, community. Participants were recruited by using random-digit dialing and U.S. census tract data from 2000 to ensure inclusion of a representative sample of the community (Appendix Figure 2). To increase participation of eligible persons in contacted households, a press release was sent to the local media and public officials and flyers were hung in public areas to heighten awareness of the study, which focused on musculoskeletal health. To be included, persons had to be at least 50 years of age and ambulatory. Bilateral total knee replacement and rheumatoid arthritis were the exclusion criteria. Rheumatoid arthritis was assessed by using a validated survey instrument (12) supplemented by questions about medication use that would reflect treated disease. Participant selection was not based on the presence or absence of knee osteoarthritis or knee pain. Appendix Figure 2. Study flow diagram: the Framingham Osteoarthritis Study community cohort. ACL = anterior cruciate ligament. *Members of Framingham Offspring Study, positive screening for rheumatoid arthritis, magnetic resonance imaging (MRI) contraindicated, bilateral knee replacement, dementia or terminal cancer, or planned to move from area. Declined to participate because of cancer, chronic illness, no interest when received full details of the study, no reason given, no time, declined MRI or radiography, or other reasons. Not done because of claustrophobia, medical contraindications, or problems with scheduling. The study was approved by the Boston University Medical Center institutional review board. All participants provided written informed consent. Assessment of Buckling We informed all participants that we are interested in knee buckling, which is also called giving way. We asked, Have you had an episode in the past 3 months where your knee buckled or gave way? Persons who answered yes were asked to indicate which knee gave way, how many times in the past 3 months they had had such an episode, and whether knee buckling precipitated a fall. We also asked what they were doing when their knee buckled and offered 4 options (they could choose more than 1): walking, going up or down stairs, twisting or turning, or other. We chose a 3-month period because other studies have suggested that recollection of falling was accurate for approximately 3 months after the event (13). We considered a person who answered yes to the initial question on buckling as having experienced buckling. We also examined the subgroup of participants who had had more than 1 episode of buckling in the past 3 months. Pain, Physical Limitation, and Assessment of Risk Factors We asked participants about knee symptoms by using the following question: In the past 30 days, have you had any pain, aching, or stiffness in either of your knees? We considered all persons who said yes to have knee pain. A positive response triggered the follow-up question, Is the pain, aching, or stiffness in your right knee, left knee, or both knees? We assessed knee pain in the past week by using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire, a validated instrument for assessment of knee pain and disability (14). To evaluate the effect of buckling on physical function or limitation, we used WOMAC and the Short Form (SF-12) as self-reported measures of physical function or limitation. The WOMAC has a physical function subscale consisting of 17 questions, each of which asks about a different type of activity and whether knee problems limit the respondent in performing those activities. Each item is scored on a scale of 0 to 4 on the basis of the amount of limitation experienced; the total score ranges from 0 to 68, with 68 constituting profound limitation and 0 constituting none. In addition, we used items from the SF-12 (15, 16) to gather information on specific physical functional limitations that might be affected by buckling. The items we focused on from the SF-12 were whether participants were limited in moderate activities, in climbing several flights of stairs, and in the type of work or other activities they could do and whether they accomplished less than they wanted. Isometric quadriceps strength was measured while participants were sitting in a straight-backed chair by using a strain gauge dynamometer strapped to the lower leg. The force exerted when the knee was extended was recorded. Three measurements were made on each leg, and the maximum of the 3 was chosen as the measure of leg strength. For a person, we used the maximal leg strength. More than 90% of participants had all assessments completed during 1 clinic visit. Occasionally, participants were scheduled to return within 2 weeks for magnetic resonance imaging (MRI). Radiographic Assessments All participants underwent bilateral weight-bearing radiography using a posteroanterior fixed-flexion approach with a SynaFlex frame (Synarc, San Francisco, California), and a lateral weight-bearing semiflexed film was obtained according to a recently published protocol (17). Radiographs were scored on the KellgrenLawrence scale (18); a knee was considered to have radiographic osteoarthritis if its grade was 2 or greater. Patellofemoral osteoarthritis was characterized on the lateral view by using a validated approach (19). A bone and joint radiologist and an experienced rheumatologist each read roughly one half of the films. The intrareader value for KellgrenLawrence grade was 0.82, an

Defining radiographic incidence and progression of knee osteoarthritis: suggested modifications of the Kellgren and Lawrence scale

In the 1950s, Kellgren and Lawrence carried out the first large-scale epidemiological studies of osteoarthritis. Obtaining x-rays on multiple subjects from the populations of various communities in England, they defined a grading scale for osteoarthritis that is still widely used and called by their names, the Kellgren and Lawrence (K&L) scale.1 This osteophyte-based scale is used in most large and small-scale clinical and epidemiological studies to define whether osteoarthritis is present or absent on the radiograph. Unfortunately, neither Kellgren and Lawrence nor subsequent users of their scale were consistent in how they described each of their grades. Importantly, for grade 2, which usually defines whether osteoarthritis is present, it has been labelled as ‘definite osteophyte’ to ‘definite osteophyte with possible narrowing of the joint space’. As noted by Schiphof and colleagues,2 3 as investigators have come up with various descriptions of K&L grade 2, each of these studies may have identified a somewhat different group of persons with radiographic knee osteoarthritis. With the emergence of large longitudinal studies of osteoarthritis have come questions about how to define new-onset disease and progressive disease, questions that the K&L scale was never designed to address. Even so, many studies, especially large epidemiological investigations, have used the K&L scale to identify knees with new-onset disease or progressive disease. In the Framingham and Rotterdam Studies,4 5 for example, investigators have defined new-onset disease as the emergence of K&L grade 2 disease in knees that had previously been graded as either K&L grades 0 or 1. Rotterdam Study investigators have alternatively used as disease incidence the new onset of K&L grade 1 in knees previously graded as grade 0.5 Progression of extant disease has also been characterised using K&L grades with progression by one grade or more often listed as one criterion …

Postoperative proximal migration in total shoulder arthroplasty. Incidence and significance.

Abstract A retrospective review of 131 Neer total shoulder arthroplasties in 111 patients performed between 1974 and 1986 was undertaken to identify factors associated with proximal humeral migration. The influence of proximal migration on results was evaluated to clarify the indications for prosthetic constraint. The average follow-up period was 55 months (range: 24–124 mo). The results showed proximal migration in 22% of patients (29 shoulders). The migration was progressive in all cases, without corresponding increases in pain. Major rotator cuff tears were present in 21% of patients with a normal glenohumeral relationship and in 24% of the patients with proximal migration. Limited elevation was noted in patients with proximal migration, but all patients had improved range of motion and decreased postoperative pain. The cause of postoperative proximal migration is believed to be secondary to a combination of factors and not rotator cuff disruption alone. These data do not support the routine use of a constrained prosthesis for irreparable rotator cuff tears