Osteonecrosis is a major treatment complication of pediatric leukemias owing to its potential to cause joint deterioration. Because of potential long-term effects of osteonecrosis on joints, information regarding its progression and collapse in different patients can be used to identify high-risk groups, advise the patients and parents of this complication, and potentially consider the risk for development of osteonecrosis in planning primary treatment.
We therefore determined: (1) the incidence of joint collapse and/or pain in young patients with hematologic malignancies diagnosed with ON of the knee; (2) risk factors associated with collapse; and (3) the relationship between size and location of osteonecrotic knee lesions and the likelihood of joint collapse.
Patients and Methods
We retrospectively reviewed 109 patients with hematologic malignancies and MRI-confirmed knee osteonecrosis. The median age was 11.5 years (range, 2.3–18.8 years) at primary diagnosis of hematologic malignancy and a median age of 13.4 years (range, 2.7–23.3 years) at diagnosis of osteonecrosis of the knee. For analyses, we used the first and last MR images. Minimum clinical followup was 2.3 years after diagnosis of knee osteonecrosis (median, 6 years; range, 2.3–7.17 years).
Joint collapse occurred in 22% (24 of 109). Older age, pain at osteonecrosis presentation, and lesions extending to the articular surface of distal femoral epiphyses were associated with joint collapse.
Younger patients and those without extensive femoral epiphyseal involvement have a better prognosis for osteonecrosis of the knee.
Level of Evidence
Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.
The mobile bearing knee system was introduced to lessen contact stress on the articular bearing surface and reduce polyethylene wear. The purpose of the current study was to investigate the mid-term results of patients undergoing total knee arthroplasties (TKAs) using Scorpio Plus Mobile Bearing Knee System (Stryker, Mahwah, NJ), and compare the outcomes between patients with osteoarthritis and osteonecrosis (OA·ON group) and patients with rheumatoid arthritis (RA group).
Eight males and 58 females were followed up for a period of 4.4- 7.6 years from June 1, 2003 to December 31, 2005. There were 53 knees with osteoarthritis, 17 knees with rheumatoid arthritis, and 6 knees with osteonecrosis. Clinical and radiographic follow- up was done using The Japanese Orthopedic Association knee rating score (JOA score) and Knee Society Total Knee Arthroplasty Roentgenographic Evaluation and Scoring System.
With regard to the JOA score, there was significant improvement in both groups. The postoperative range of motion was between 0.8°and 116.8° in OA·ON group, and between 0.0° and 113.7° in RA group. There were no significant differences with the radiographic evaluation between two groups. Spontaneous dislocation of a polyethylene insert occurred in one patient, and deep infection was occurred in one patient.
There was significant improvement with regard to the clinical and radiographic results of patients undergoing TKAs using the model. The risk of polyethylene insert dislocation related to the mobile bearing TKA is a cause for concern.
Total knee arthroplasty; Mobile- bearing design; Osteoarthritis; Rheumatoid arthritis
Objective: Spontaneous osteonecrosis of the knee affects patients typically over the age of fifty-five years. Evidence exists that this process may not be true necrosis. The purpose of this study was to characterize the demographic, radiographic, and pathologic features of this condition.
Materials and Methods: Twenty-one patients (twenty-two knees) consecutively treated for spontaneous osteonecrosis of the knee were studied.
Results: Only one of twenty-two specimens demonstrated evidence of bone necrosis. No specimens showed fat necrosis, marrow necrosis, fibrous change or appositional bone repair. Fourteen of twenty-two specimens (64%) showed significant osteopenia and fifteen of twenty-two specimens (68%) showed evidence of osteoarthritis.
Conclusions: This study demonstrated that spontaneous osteonecrosis of the knee is not an osteonecrotic condition and has been misnamed. Osteopenia and osteoarthritis may play a role in the pathogenesis of this disease.
We analyzed the clinical and radiologic results of patients with spontaneous osteonecrosis of the knee treated by minimally invasive medial unicompartmental arthroplasty using Oxford Uni.
We reviewed 22 knees in 21 patients which were treated for spontaneous osteonecrosis between 2002 and 2006. Patients included one male and 20 females. The mean age was 70.8 years (range, 53 to 82 years). The mean follow-up period was 70.3 months (range, 48 to 93 months). The clinical results were evaluated using the Hospital for Special Surgery (HSS) knee score and the range of motion of the knee preoperatively and at the final follow-up. Preoperative plain radiographs and magnetic resonance images were analyzed to determine the size and stage of osteonecrotic lesions.
The mean HSS knee score was 64.3 (range, 54 to 75) preoperatively and 92.0 (range, 71 to 100) at the final follow-up. The mean preoperative flexion contracture was 8.9° (range, 0 to 15°) and 0.2° (range, 0 to 5°) at the final follow-up. The mean further flexion increased from 138.6° (range, 100 to 145°) preoperatively to 145.6° (range, 140 to 150°) at the final follow-up. Active full flexion was possible within 2 months of the operation. The squatting position was possible in 16 patients (84.2%) out of 19, except one case of bronchiectasis and one case of spine fracture. The cross-leg posture was possible in 19 patients (90.5%) out of 21. The mean tibiofemoral angle was improved from varus 0.98° to valgus 3.22°. Meniscal bearing dislocation occurred in 2 cases and femoral component loosening occurred in 1 case.
Unicompartmental knee arthroplasty using Oxford Uni could be an alternative treatment option in spontaneous osteonecrosis of the knee.
Knee; Spontaneous osteonecrosis; Unicompartmental knee arthroplasty
While the literature suggests lateral unicondylar knee arthroplasty (UKA) improves function in the short- and medium-term, it is less clear on longer-term function. We asked (1) whether lateral UKA improved longer-term Knee Society scores and return to previous activity level); (2) whether there were any concerning longer-term radiographic findings (the Knee Society roentgenographic evaluation and scoring system); and (3) whether lateral UKA was durable as measured by survivorship to revision at 10 and 16 years. We retrospectively reviewed 39 patients with 40 lateral cemented metal-backed UKA. The patients had a mean age of 61 years at surgery. The etiologies were primary osteoarthritis in 24 knees, posttraumatic in 12 cases, and osteonecrosis in four cases. We performed clinical and radiographic evaluations at a minimum followup of 3 years (mean, 12.6 years; range, 3–23 years). Prostheses survivorship was 92% at 10 years and 84% at 16 years. Despite the limited number of indications and technical considerations, our data suggest lateral UKA is a reasonable alternative for isolated lateral femorotibial compartment disease.
Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
Avascular necrosis of bone (osteonecrosis) can cause structural failure and subsequent deformation, leading to joint dysfunction and pain. Structural failure is the result of resorption of necrotic bone during revascularization, before new bone has formed or consolidated enough for loadbearing. Bone resorption can be reduced by bisphosphonates. If resorption of the necrotic bone could be reduced during the revascularization phase until sufficient new bone has formed, it would appear that structural failure could be avoided.
To test whether resorption of necrotic bone can be prevented, structural grafts were subjected to new bone ingrowth during systemic bisphosphonate treatment in a rat model.
In rats treated with alendronate the necrotic bone was not resorbed, whereas it was almost entirely resorbed in the controls.
Systemic alendronate treatment prevents resorption of necrotic bone during revascularization. In patients with osteonecrosis, bisphosphonates may therefore prevent collapse of the necrotic bone.
Although the severity of knee osteoarthritis (OA) usually is assessed using different measures of joint structure, function, and pain, the relationships between these measures are unclear.
Therefore, we: (1) examined the relationships between the measures of knee structure (flexion-extension range of motion, radiographic tibiofemoral angle, and medial joint space), function (Knee Osteoarthritis Outcome Scores [KOOS], peak adduction angle, and moment), and pain (visual analog scale [VAS]); and (2) identified variables that best predicted knee pain.
We assessed 15 patients with medial knee OA using VAS pain, KOOS questionnaire, 3-D gait analysis, and radiographic examination. Parameter relationships were assessed using Pearson correlation, and variables most predictive of knee pain were determined using a stepwise multiple regression.
Subjective measurements correlated (|r| ≥ 0.54) with one another, as did most of the objective measurements (|r| ≥ 0.56) except for adduction moment which did not correlate with any variable. All variables correlated (|r| > 0.54) with VAS knee pain except peak adduction moment. Medial joint space and peak adduction angle best predicted knee pain, accounting for approximately three-quarters of the model variance (r2 = 0.73).
Medial joint space and peak adduction angle may be useful for predicting knee pain in patients with medial knee OA. Therapies that target these structural and functional variables may reduce knee pain in this population.
Increasing the medial joint space and limiting the peak knee adduction angle may be critical in achieving effective pain relief in patients with varus knee OA.
One hundred consecutive admissions to an acute geriatric unit were examined for clinical and radiographic evidence of osteoarthritis (OA) and articular chondrocalcinosis (ACC). Thirty-four patients had ACC. This was age related, the prevalence rising from 15% in patients aged 65-74 years to 44% in patients over 84 years. The commonly involved joints were the knee (25%), public symphysis (15%), and wrist (9%). No other aetiological factors predisposing to ACC were found. Of the 25 patients with ACC in the knee 7 had no symptoms or signs and no radiographic evidence of OA at that site. However, the combination of ACC and radiographic OA was characterised by an increase in clinical joint disease. Features of inflammation (joint swelling and joint line tenderness) involving the knee, wrist, and elbow were particularly common in ACC. It is concluded that ACC is common in the elderly and is associated with an increased incidence of joint disease.
The aim of our study was to determine the radiographic prevalence of hip and knee osteoarthritis and compare our results with prevalence data reported by other studies, as no similar study had been performed in Hungary previously. Our aim was also to investigate the usefulness of the different radiological scoring methods for the definition of osteoarthritis. Patients who earlier reported complaints and gave written consent were asked to participate in a clinical follow-up. In the 682 participants Harris hip score, visual analogue pain scale values for both joints, Knee Society score and knee functional score were calculated. Weight-bearing radiographs were taken of both joints. Kellgren-Lawrence radiological evaluation was performed and osteoarthritis prevalence was defined. Hip osteoarthritis was found in 109 cases (16.49%), and knee osteoarthritis was found in 111 cases (16.54%). Harris hip score, Knee Society score, functional score and visual analogue scale values were significantly worse in people with radiographically proven osteoarthritis compared to the control group (p < 0.05). Significantly higher osteoarthritis prevalence of both joints was found in those with increased body mass index values. Age also plays a significant role in the development of both hip and knee osteoarthritis. No significant difference was observed between male and female participants regarding osteoarthritis prevalence. The Kellgren-Lawrence score with a cut-off value of 2 or more is a useful evaluation method for the detection of osteoarthritis prevalence in epidemiological studies; according to our observations, in clinical practice a cut-off value of three or more is more relevant.
Studies have suggested that the symptoms of knee osteoarthritis (OA) are rather weakly associated with radiographic findings and vice versa. Our objectives were to identify estimates of the prevalence of radiographic knee OA in adults with knee pain and of knee pain in adults with radiographic knee OA, and determine if the definitions of x ray osteoarthritis and symptoms, and variation in demographic factors influence these estimates.
A systematic literature search identifying population studies which combined x rays, diagnosis, clinical signs and symptoms in knee OA. Estimates of the prevalence of radiographic OA in people with knee pain were determined and vice versa. In addition the effects of influencing factors were scrutinised.
The proportion of those with knee pain found to have radiographic osteoarthritis ranged from 15–76%, and in those with radiographic knee OA the proportion with pain ranged from 15% – 81%. Considerable variation occurred with x ray view, pain definition, OA grading and demographic factors
Knee pain is an imprecise marker of radiographic knee osteoarthritis but this depends on the extent of radiographic views used. Radiographic knee osteoarthritis is likewise an imprecise guide to the likelihood that knee pain or disability will be present. Both associations are affected by the definition of pain used and the nature of the study group. The results of knee x rays should not be used in isolation when assessing individual patients with knee pain.
Background and purpose Early migration of joint replacements is an effect of poor fixation and can predict late loosening. By reducing the bone resorption after implantation of a joint replacement, it should be possible to enhance the initial fixation of the implant. We studied the effect of once-weekly treatment with alendronate after knee replacement.
Patients and methods We recruited 60 patients (60 knees) with gonarthrosis who were scheduled for a total knee replacement. They were operated on with identical implants and uncemented fixation. 30 patients were treated with a bisphosphonate (alendronate) and 30 patients underwent placebo treatment. The treatment started postoperatively and continued on a weekly basis for 6 months. The fixation of the implants was measured with repeated radiostereometry for 2 years.
Results There was no difference in migration of implants between the two groups.
Conclusion With uncemented fixation of knee implants, no benefit of once-weekly treatment with alendronate, starting postoperatively, could be seen during a 2-year follow-up period.
A recent study of adults aged ≥50 years reporting knee pain found an excess of radiographic knee osteoarthritis (knee ROA) in symptomatic males compared to females. This was independent of age, BMI and other clinical signs and symptoms. Since this finding contradicts many previous studies, our objective was to explore four possible explanations for this gender difference: X-ray views, selection, occupation and non-articular conditions.
A community-based prospective study. 819 adults aged ≥50 years reporting knee pain in the previous 12 months were recruited by postal questionnaires to a research clinic involving plain radiography (weight-bearing posteroanterior semiflexed, supine skyline and lateral views), clinical interview and physical examination. Any knee ROA, ROA severity, tibiofemoral joint osteoarthritis (TJOA) and patellofemoral joint osteoarthritis (PJOA) were defined using all three radiographic views. Occupational class was derived from current or last job title. Proportions of each gender with symptomatic knee ROA were expressed as percentages, stratified by age; differences between genders were expressed as percentage differences with 95% confidence intervals.
745 symptomatic participants were eligible and had complete X-ray data. Males had a higher occurrence (77%) of any knee ROA than females (61%). In 50–64 year olds, the excess in men was mild knee OA (particularly PJOA); in ≥65 year olds, the excess was both mild and moderate/severe knee OA (particularly combined TJOA/PJOA). This male excess persisted when using the posteroanterior view only (64% vs. 52%). The lowest level of participation in the clinic was symptomatic females aged 65+. Within each occupational class there were more males with symptomatic knee ROA than females. In those aged 50–64 years, non-articular conditions were equally common in both genders although, in those aged 65+, they occurred more frequently in symptomatic females (41%) than males (31%).
The excess of knee ROA among symptomatic males in this study seems unlikely to be attributable to the use of comprehensive X-ray views. Although prior occupational exposures and the presence of non-articular conditions cannot be fully excluded, selective non-participation bias seems the most likely explanation. This has implications for future study design.
In osteonecrosis the vascular supply of the bone is interrupted and the living cells die. The inorganic mineral network remains intact until ingrowing blood vessels invade the graft. Accompanying osteoclasts start to resorb the bone trabeculae and gradually replace the bone. If the osteonecrosis occurs in mechanically loaded parts, like in the subchondral bone of a loaded joint, the remodelling might lead to a weakening of the bone and, in consequence to a joint collapse. Systemic bisphosphonate treatment can reduce the resorption of necrotic bone. In the present study we investigate if zoledronate, the most potent of the commercially available bisphosphonates, can be used to reduce the amount or speed of bone graft remodeling.
Bone grafts were harvested and placed in a bone chamber inserted into the tibia of a rat. Host tissue could grow into the graft through openings in the chamber. Weekly injections with 1.05 μg zoledronate or saline were given subcutaneously until the rats were harvested after 6 weeks. The specimens were fixed, cut and stained with haematoxylin/eosin and used for histologic and histomorphometric analyses.
By histology, the control specimens were almost totally resorbed in the remodeled area and the graft replaced by bone marrow. In the zoledronate treated specimens, both the old graft and new-formed bone remained and the graft trabeculas were lined with new bone. By histomorphometry, the total amount of bone (graft+ new bone) within the remodelled area was 35 % (SD 13) in the zoledronate treated grafts and 19 % (SD 12) in the controls (p = 0.001). Also the amount of new bone was increased in the treated specimens (22 %, SD 7) compared to the controls (14 %, SD 9, p = 0.032).
We show that zoledronate can be used to decrease the resorption of both old graft and new-formed bone during bone graft remodelling. This might be useful in bone grafting procedure but also in other orthopedic conditions, both where necrotic bone has to be remodelled i.e. after osteonecrosis of the knee and hip and in Perthes disease, or in high load, high turnover conditions like delayed union, periprosthetic osteolysis or bone lengthening operations. In our model an increased net formation of new bone was found which probably reflects that new bone formed was retained by the action of the bisphosphonates rather than a true anabolic effect.
OBJECTIVES—Different prevalences of generalised osteoarthritis (GOA) in patients with knee and hip OA have been reported. The aim of this investigation was to evaluate radiographic and clinical patterns of disease in a hospital based population of patient subgroups with advanced hip and knee OA and to compare the prevalence of GOA in patients with hip or knee OA, taking potential confounding factors into account.
METHODS—420 patients with hip OA and 389 patients with knee OA scheduled for unilateral total joint replacement in four hospitals underwent radiographic analysis of ipsilateral and contralateral hip or knee joint and both hands in addition to a standardised interview and clinical examination. According to the severity of radiographic changes in the contralateral joints (using Kellgren-Lawrence ⩾ grade 2 as case definition) participants were classified as having either unilateral or bilateral OA. If radiographic changes of two joint groups of the hands (first carpometacarpal joint and proximal/distal interphalangeal joints defined as two separate joint groups) were present, patients were categorised as having GOA.
RESULTS—Patients with hip OA were younger (mean age 60.4 years) and less likely to be female (52.4%) than patients with knee OA (66.3 years and 72.5% respectively). Intensity of pain and functional impairment at hospital admission was similar in both groups, while patients with knee OA had a longer symptom duration (median 10 years) compared with patients with hip OA (5 years). In 41.7% of patients with hip OA and 33.4% of patients with knee OA an underlying pathological condition could be observed in the replaced joint, which allowed a classification as secondary OA. Some 82.1% of patients with hip and 87.4% of patients with knee OA had radiographic changes in their contralateral joints (bilateral disease). The prevalence of GOA increased with age and was higher in female patients. GOA was observed more often in patients with knee OA than in patients with hip OA (34.9% versus 19.3%; OR=2.24; 95% CI: 1.56, 3.21). Adjustment for the different age and sex distribution in both patient groups, however, takes away most of the difference (OR=1.32; 95% CI: 0.89, 1.96).
CONCLUSION—The crude results confirm previous reports as well as the clinical impression of GOA being more prevalent in patients with advanced knee OA than in patients with advanced hip OA. However, these different patterns might be attributed to a large part to a different distribution of age and sex in these hospital based populations.
Keywords: hip osteoarthritis; knee osteoarthritis; hand osteoarthritis; generalised osteoarthritis
To determine the efficacy and safety of risedronate in patients with knee osteoarthritis (OA), the British study of risedronate in structure and symptoms of knee OA (BRISK), a 1-year prospective, double-blind, placebo-controlled study, enrolled patients (40–80 years of age) with mild to moderate OA of the medial compartment of the knee. The primary aims were to detect differences in symptoms and function. Patients were randomized to once-daily risedronate (5 mg or 15 mg) or placebo. Radiographs were taken at baseline and 1 year for assessment of joint-space width using a standardized radiographic method with fluoroscopic positioning of the joint. Pain, function, and stiffness were assessed using the Western Ontario and McMaster Universities (WOMAC) OA index. The patient global assessment and use of walking aids were measured and bone and cartilage markers were assessed. The intention-to-treat population consisted of 284 patients. Those receiving risedronate at 15 mg showed improvement of the WOMAC index, particularly of physical function, significant improvement of the patient global assessment (P < 0.001), and decreased use of walking aids relative to patients receiving the placebo (P = 0.009). A trend towards attenuation of joint-space narrowing was observed in the group receiving 15 mg risedronate. Eight percent (n = 7) of patients receiving placebo and 4% (n = 4) of patients receiving 5 mg risedronate exhibited detectable progression of disease (joint-space width ≥ 25% or ≥ 0.75 mm) versus 1% (n = 1) of patients receiving 15 mg risedronate (P = 0.067). Risedronate (15 mg) significantly reduced markers of cartilage degradation and bone resorption. Both doses of risedronate were well tolerated. In this study, clear trends towards improvement were observed in both joint structure and symptoms in patients with primary knee OA treated with risedronate.
Traditionally the management of any chronic condition starts with its diagnosis. The labelling of disease can be beneficial in terms of defining appropriate treatment such as in coronary artery disease. However, sometimes it may be detrimental such as when x-rays are used to diagnose lumbar spondylosis leading to patients inappropriately limiting their activity. Chronic knee pain in the elderly is another example where applying labels is problematical. A common diagnosis in this situation is osteoarthritis, but this label can be applied in two ways: as a radiological diagnosis, or as a clinical one. The x-ray diagnosis, however, does not equate with the clinical syndrome, and vice versa. In addition, diagnosing knee pain as osteoarthritis does not necessarily help in management, since a patient's debility is more dependent upon their clinical signs and symptoms than the presence of radiographic osteoarthritis, and by the same token its clinical counterpart. GPs are consistent in their management of knee pain, but in attempting to diagnose the pain as osteoarthritis, these plans can alter and become more dependent on the actual diagnosis than the clinical picture. As a result management may well diverge from what the current best evidence supports. Diagnosis for diagnosis sake, should therefore be discouraged, and chronic knee pain gives us one example of why this is the case. GPs would be better placed to manage this condition if it was considered more as a regional pain syndrome, perhaps defining it simply as ‘chronic knee pain in older people’. This example suggests that there is a pressing need in primary care to carefully consider in chronic disease when it is appropriate to be definitive in diagnosis such that when using disease specific labels, there is definite benefit for the patient and doctor.
chronic disease; diagnosis; knee osteoarthritis; radiography
Osteoarthritis is a prevalent disease in older patients of all racial groups, and it is known to cause significant pain and functional disability. Racial differences in how patients cope with the chronic pain of knee or hip osteoarthritis may have implications for utilization of treatment modalities such as joint replacement. Therefore, we examined the relationships between patient race and pain coping strategies (diverting attention, reinterpreting pain, catastrophizing, ignoring sensations, hoping and praying, coping self-statements, and increasing behavior activities) for hip and knee osteoarthritis. This is a cross-sectional survey of 939 veterans 50 to 79 years old with chronic hip or knee osteoarthritis pain recruited from VA primary care clinics in Philadelphia and Pittsburgh. Patients had to have moderate to severe hip or knee osteoarthritis symptoms as measured by the WOMAC index. Standard, validated instruments were used to obtain information on attitudes and use of prayer, pain coping strategies, and arthritis self-efficacy. Analysis included separate multivariable models adjusting for demographic and clinical characteristics. Attitudes on prayer differed, with African Americans being more likely to perceive prayer as helpful (adjusted OR=3.38, 95% CI 2.35 to 4.86) and to have tried prayer (adjusted OR=2.28, 95% 1.66 to 3.13) to manage their osteoarthritis pain. Upon evaluating the coping strategies, we found that, compared to whites, African Americans had greater use of the hoping and praying method (β=0.74, 95% CI 0.50 to 0.99). Race was not associated with arthritis pain self-efficacy, arthritis function self-efficacy, or any other coping strategies. This increased use of the hoping and praying coping strategy by African Americans may play a role in the decreased utilization of total joint arthroplasty among African Americans compared to whites. Further investigation of the role this coping strategy has on the decision making process for total joint arthroplasty should be explored.
Coping strategies; Health disparities; Joint arthroplasty; Osteoarthritis; Prayer
Osteonecrosis is a phenomenon involving disruption to the vascular supply to the femoral head, resulting in articular surface collapse and eventual osteoarthritis. Although alcoholism, steroid use, and hip trauma remain the most common causes, several other etiologies for osteonecrosis have been identified. Basic science research utilizing animal models and stem cell applications continue to further elucidate the pathophysiology of osteonecrosis and promise novel treatment options in the future. Clinical studies evaluating modern joint-sparing procedures have demonstrated significant improvements in outcomes, but hip arthroplasty is still the most common procedure performed in these affected younger adults. Further advances in joint-preserving procedures are required and will be widely studied in the coming decade.
Osteonecrosis; Avascular necrosis; Femoral head; Total hip arthroplasty; Core decompression; Hip
OBJECTIVES—To determine the prevalence of tibiofemoral radiographic knee osteoarthritis (OA) in people aged 35-54 years associated with chronic (> 3 months) knee pain using two different radiographic grading systems.
METHODS—Population based postal survey in a random sample of inhabitants in a district in southern Sweden followed by clinical examination and plain posteroanterior, weight bearing radiographical examination. The Ahlbäck criteria (focusing on joint space narrowing) and the Kell- gren & Lawrence classification for knee OA were used for diagnosing tibiofemoral OA.
RESULTS—A questionnaire was sent to 2000 randomly selected people aged 35-54 years. The response rate was 92.6%. Fifteen per cent of these people reported chronic knee pain. This group (n=279) was offered a clinical and radiographic examination of the knee joint and 204 persons agreed to participate. According to the Kellgren & Lawrence classification 28 subjects had OA of the knee grade 2 or more and 16 grade 3 or more. Radiographically detected OA of the knee according to Ahlbäck was found in 20 cases. The minimum prevalence of radiological tibiofemoral knee OA with knee pain was thus 1.5% for Kellgren & Lawrence grade 2 or more, 0.9% for grade 3 or more, and 1.1% according to the Ahlbäck classification. The agreement between the Kellgren & Lawrence grades 2-3 versus Ahlbäck grade I as well as grade 3-4 versus Ahlbäck grade I-II was good (κ 0.76 and 0.78 respectively).
CONCLUSION—The prevalence of radiographic tibiofemoral OA combined with chronic knee pain in people aged 35-54 years was around 1% as estimated by either the Kellgren & Lawrence or the Ahlbäck classifications systems. Prospective follow up of this cohort should elucidate the significance of knee pain as a sign of developing OA.
Many previous reports suggest total hip arthroplasty performs suboptimally in young patients with osteonecrosis. We retrospectively compared the performance of metal-on-metal articulation in a select group of 107 patients with 112 hips (98 uncemented and 14 cemented stems) 60 years of age or younger with either osteonecrosis (27 patients, 30 hips) or primary osteoarthritis (80 patients, 82 hips). We evaluated all patients with patient-generated Harris hip score forms and serial radiographs. Five mechanical complications were caused by impingement, two with pain, two dislocations, and one liner dissociation. At a minimum followup of 2.2 years (mean, 5.5 years; range, 2.2–11.7 years), we observed no osteolysis or aseptic loosening in the osteonecrosis group, whereas one osteoarthritic hip had cup revision for loosening (none showed evidence of osteolysis). None of the stems were loose. Patients with osteonecrosis or primary osteoarthritis were similar in clinical and radiographic performance. The patients with metal-on-metal hip arthroplasty for osteonecrosis had no revisions for aseptic loosening, but did have one liner change in a cup for painful impingement.
Level of Evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
While knee osteoarthritis has been shown to affect a multitude of kinematic, kinetic and temporo-spatial gait parameters, few investigations have examined the effect of increasing levels of radiographic osteoarthritis severity on these gait parameters. Fewer still have investigated the effect of walking speed on gait variables in persons with knee osteoarthritis. The objective of this study was to investigate the influence of walking speed on biomechanical variables associated with joint loading in persons with varying severities of medial compartment knee osteoarthritis.
Twenty-one persons with moderate osteoarthritis (Kellgren-Lawrence score 2–3) and 13 persons with severe osteoarthritis (Kellgren-Lawrence score of 4) participated. Twenty-two persons without knee pain or radiographic evidence of arthritis comprised a healthy control group. Sagittal plane kinetics, knee adduction moment, sagittal plane knee excursion, ground reaction forces and knee joint reaction forces were calculated from 3-dimensional motion analysis at 1.0 m/s, self-selected and fastest tolerable walking speeds. Differences were analyzed using multivariate analysis of variance and multivariate analysis of covariance with speed as a covariate.
Persons with knee osteoarthritis showed significantly lower knee and ankle joint moments, ground reaction forces, knee reaction force and knee excursion when walking at freely chosen speeds. When differences walking in speed were accounted for in the analysis, the only difference found at all conditions was decreased knee joint excursion.
Compared to a healthy control group, persons with knee OA demonstrate differences in joint kinetics and kinematics. Except for knee excursion, these differences in gait parameters appear to be a result of slower freely chosen walking speeds rather than a result of disease progression.
A subchondral insufficiency fracture (SIF) of the femoral head is a recently proposed concept, which needs to be differentiated from osteonecrosis. Clinically, SIF has generally been observed in the osteoporotic elderly women or renal transplant recipients. Radiographical changes are not obvious in its early phase, however, some cases undergo subchondral collapse (crescent sign). On the T1-weighted magnetic resonance images, a low intensity band is one of the characteristic imaging appearances, which corresponds histologically to the fracture line and associated fracture repair tissue. Therefore, the shape of the low intensity band generally tends to be irregular, disconnected, and convex to the articular surface. The prognosis of SIF is not clearly established. Some cases show resolution of the symptoms by the conservative treatments, while other cases show rapid progression of the collapse such as rapidly progressive arthrosis of the hip.
Subchondral insufficiency fracture; Femoral head; Osteoporosis; Osteonecrosis
Clinical, radiographic, and scintigraphic abnormalities of the knee joint have been correlated in a cross sectional study of 100 patients with osteoarthritis. The group comprised 73 women and 27 men with a mean age of 65.7 years. One hundred and ninety one of the 200 knees had clinical (175) or radiographic (185) evidence of osteoarthritis, or both (161). Scintigraphic images of the knees were obtained 4-5 minutes (early phase) and 2.5-3.5 hours (late phase) after intravenous injection of 600 mBq of technetium-99m diphosphonate. Abnormal images were recorded in 162 knees (81%), and six different patterns were detected. Generalised isotope retention around the knee (early or late phase) was less common than focal areas of uptake around the joint margin (early or late phase) or in the patella or subchondral bone (late phase). Some knees with abnormal scans were normal on radiography (n = 7), or vice versa (n = 21). Different scan patterns correlated with different clinical and radiographic features: the generalised pattern correlated with pain (odds ratio (OR) = 45.1) and osteophytes (OR = 48.3); joint line retention correlated with subchondral bone sclerosis on radiography (OR = 62.1); and subchondral bone retention correlated with more severe radiographic changes. It is concluded that different patterns of scintigraphic abnormality reflect various aspects of the disease process of osteoarthritis.
Osteonecrosis is a complication of corticosteroid therapy with limited treatment options in young, active patients. These options include debridement, core decompression, osteotomy, allografting, and partial or total knee replacement. Few studies exist regarding the use of osteochondral allografts for treatment of steroid-associated osteonecrosis.
We asked if fresh osteochondral allografts would (1) heal to host bone in the presence of osteonecrosis, (2) provide a clinically meaningful decrease in pain and improvement in function, and (3) prevent or postpone the need for prosthetic arthroplasty.
Patients and Methods
Twenty-two patients (28 knees) who underwent osteochondral allografting for high-grade, corticosteroid-associated osteonecrosis were evaluated. Their average age was 24.3 years (range, 16–44 years). The mean graft surface area was 10.8 cm2 (range, 5.0–19.0 cm2). Evaluation included a modified (for the knee) D’Aubigné and Postel (18-point) score, International Knee Documentation Committee (IKDC), and Knee Society function scores. The minimum followup was 25 months (mean, 67 months; range, 25–235 months).
Five knees failed. The graft survival rate was 89% (25 of 28). The mean D’Aubigné and Postel score improved from 11.3 to 15.8; 19 of 25 (76%) had a score greater than 15. The mean IKDC pain score improved from 7.1 to 2.0, mean IKDC function score from 3.5 to 8.3, and mean Knee Society function score from 60.0 to 85.7.
Our data suggest osteochondral allografting is a reasonable salvage option for osteonecrosis of the femoral condyles. TKA was avoided in 27 of the 28 of knees at last followup.
Level of Evidence
Level IV, case series. See Guidelines for Authors for a complete description of levels of evidence.
Studies on exercise in knee osteoarthritis (OA) have focused on elderly subjects. Subjects in this study were middle-aged with symptomatic and definite radiographic knee osteoarthritis. The aim was to test the effects of a short-term, high-intensity exercise program on self-reported pain, function and quality of life.
Patients aged 36–65, with OA grade III (Kellgren & Lawrence) were recruited. They had been referred for radiographic examination due to knee pain and had no history of major knee injury. They were randomized to a twice weekly supervised one hour exercise intervention for six weeks, or to a non-intervention control group. Exercise was performed at ≥ 60% of maximum heart rate (HR max). The primary outcome measure was the Knee injury and Osteoarthritis Outcome Score (KOOS). Follow-up occurred at 6 weeks and 6 months.
Sixty-one subjects (mean age 56 (SD 6), 51 % women, mean BMI 29.5 (SD 4.8)) were randomly assigned to intervention (n = 30) or control group (n = 31). No significant differences in the KOOS subscales assessing pain, other symptoms, or function in daily life or in sport and recreation were seen at any time point between exercisers and controls. In the exercise group, an improvement was seen at 6 weeks in the KOOS subscale quality of life compared to the control group (mean change 4.0 vs. -0.7, p = 0.05). The difference between groups was still persistent at 6 months (p = 0.02).
A six-week high-intensive exercise program had no effect on pain or function in middle-aged patients with moderate to severe radiographic knee OA. Some effect was seen on quality of life in the exercise group compared to the control group.