OBJECTIVE: In adults, osteoarthritis (OA) is associated with obesity and knee alignment. Whether knee alignment differences develop during childhood and are associated with obesity is unknown. We assessed the distribution of knee alignment in children and adolescents, and determined how knee alignment differs between obese and nonobese children.
METHODS: This cross-sectional study examined knee alignment in 155 healthy weight and 165 obese subjects. Knee alignment [metaphyseal-diaphyseal angle (MDA) and anterior tibiofemoral angle (ATFA)] and fat mass were measured using whole body dual-energy X-ray absorptiometry (DEXA). National reference data were used to generate age- and sex-specific body mass index (BMI, kg/m(2)) Z-scores. Multivariable linear regression was used to identify independent factors associated with ATFA and MDA.
RESULTS: The mean MDA and ATFA were similar between obese and nonobese subjects. In stratified analyses, females had greater variability in MDA and ATFA values (p < 0.001 and p = 0.04, respectively) at higher BMI Z-scores. Compared with healthy weight controls, obese subjects had less valgus of the MDA prior to the onset of puberty (+ 2.0°, p = 0.001), but had greater valgus at later pubertal stages (-1.9°, p = 0.01).
CONCLUSION: We found significantly greater variability in knee alignment among females at higher BMI Z-scores, and greater valgus alignment in obese adolescents in late puberty. The major limitation is the use of DEXA for assessment of alignment, which needs validation against longstanding radiographs. Longitudinal studies are needed to determine whether childhood obesity is a risk factor for progressive malalignment that may predispose to pain and risk of early osteoarthritis.
BACKGROUND: Knee replacements are common after hip replacement for end stage osteoarthritis. Whether abnormal knee mechanics exist in moderate hip osteoarthritis remains undetermined and has implications for understanding early osteoarthritis joint mechanics. The purpose of this study was to determine whether three-dimensional (3D) knee motion and muscle activation patterns in individuals with moderate hip osteoarthritis differ from an asymptomatic cohort and whether these features differ between contra- and ipsilateral knees.
METHODS: 3D motions and medial and lateral quadriceps and hamstring surface electromyography were recorded on 20 asymptomatic individuals and 20 individuals with moderate hip osteoarthritis during treadmill walking, using standardized collection and processing procedures. Principal component analysis was used to derive electromyographic amplitude and temporal waveform features. 3D stance-phase range of motion was calculated. A 2-factor repeated analysis of variance determined significant within-group leg and muscle differences. Student's t-tests identified between group differences, with Bonferroni corrections where applicable (α=0.05).
FINDINGS: Lower sagittal plane motion between early and mid/late stance (5°, P=0.004, effect size: 0.96) and greater mid-stance quadriceps activity was found in the osteoarthritis group (P=0.01). Compared to the ipsilateral knee, a borderline significant increase in mid-stance hamstring activity was found in the contra-lateral knee of the hip osteoarthritis group (P=0.018).
INTERPRETATION: Bilateral knee mechanics were altered, suggesting potentially increased loads and knee muscle fatigue. There was no indication that one knee is more susceptible to osteoarthritis than the other, thus clinicians should include bilateral knee analysis when treating patients with hip osteoarthritis.
BACKGROUND: Complaints of knee pain secondary to early osteoarthritis may account for up to 30% of visits to primary care physicians. Due to the proposed inflammatory changes in early osteoarthritis, intra-articular injections of corticosteroids (IACS) have been considered as an option for disease progression modification, pain control, and improvement of function. However, some studies have suggested poor accuracy rates of IA injections depending on the entry site chosen. It is therefore the aim of this study to evaluate the efficacy of IA knee corticosteroid injection in reducing pain and improving function in patients with early osteoarthritis and whether the low accuracy rates reported with the Anterolateral joint line injection site translate to worse functional and pain outcome measures as compared to Suprapatellar lateral injections.
MATERIALS AND METHODS: The study was carried out as an open-label, randomized controlled trial with 60 sequential patients recruited. Simple randomization separated groups into anterolateral joint line or suprapatellar lateral injection sites. Improvements were measured with WOMAC and VAS scores after injection of Lidocaine and steroid solution.
RESULTS: Patients receiving IACS injections had a measurable improvement in self-reported outcomes as evidenced by standard deviation change in WOMAC and VAS scores. The majority of patients had a clinically significant improvement in VAS scores as compared to their initial measures with a notable amount of patients improving significantly as well on their WOMAC scores, irrespective of the injection site chosen.
CONCLUSIONS: We have therefore continued the use of palpation-guided intra-articular knee injections in an effort to reduce costs as compared to other injection modalities with positive results in our osteoarthritis patients.
RATIONALE AND OBJECTIVES: The objectives of this research study were to determine the magic-angle effect on different subregions of in vivo human femoral cartilage through the quantitative assessment of the effect of static magnetic field orientation (B0) on transverse (T2) relaxation time at 3.0 T.
MATERIALS AND METHODS: Healthy volunteers (n = 5; mean age, 36.4 years) and clinical patients (n = 5; mean age, 64 years) with early osteoarthritis (OA) were scanned at 3.0-T magnetic resonance using an 8-channel phased-array knee coil (transmit-receive).
RESULTS: The T2 maps revealed significantly greater values in anterior than in posterior regions. When the cartilage regions were oriented at 55° to B0 (magic angle), the longest T2 values were detected in comparison with the neighboring regions oriented 90° and 180° (0°) to B0. The subregions oriented 180° (0°) to B0 showed the lowest T2 values.
CONCLUSIONS: The differences in T2 values of different subregions suggest that magic-angle effect needs to be considered when interpreting cartilage abnormalities in OA patients.
OBJECTIVE: To investigate associations of biochemical markers of joint metabolism and inflammation with minimum joint space width (JSW) and osteophyte area (OP area) of knees showing no or doubtful radiographic osteoarthritis (OA) and to investigate whether these differed between painful and non-painful knees.
DESIGN: Serum (s-) and urinary (u-) levels of the cartilage markers uCTX-II, sCOMP, sPIIANP, and sCS846, bone markers uCTX-I, uNTX-I, sPINP, and sOC, synovial markers sPIIINP and sHA, and inflammation markers hsCRP and erythrocyte sedimentation rate (ESR) were assessed in subjects from CHECK (Cohort Hip and Cohort Knee) demonstrating Kellgren and Lawrence grade ≤1 OA on knee radiographs. Minimum JSW and OP area of these knees were quantified in detail using Knee Images Digital Analysis (KIDA).
RESULTS: uCTX-II levels showed negative associations with minimum JSW and positive associations with OP area. sCOMP and sHA levels showed positive associations with OP area, but not with minimum JSW. uCTX-I and uNTX-I levels showed negative associations with minimum JSW and OP area. Associations of biochemical marker levels with minimum JSW were similar between painful and non-painful knees, associations of uCTX-II, sCOMP, and sHA with OP area were only observed in painful knees.
CONCLUSIONS: In these subjects with no or doubtful radiographic knee OA, uCTX-II might not only reflect articular cartilage degradation but also endochondral ossification in osteophytes. Furthermore, sCOMP and sHA relate to osteophytes, maybe because synovitis drives osteophyte development. High bone turnover may aggravate articular cartilage loss. Metabolic activity in osteophytes and synovial tissue, but not in articular cartilage may be related to knee pain.
OBJECTIVE: Early detection of osteoarthritis (OA) would increase the chances of effective intervention. We aimed to investigate which patient-reported activity is first associated with knee pain. We hypothesized that pain would occur first during activities requiring weight bearing and knee bending.
METHODS: Data were obtained from the Osteoarthritis Initiative (OAI), a multicenter, longitudinal prospective observational cohort of people who have or are at high risk of OA. Participants completed the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC; Likert scale) annually for up to 7 years. Rasch analysis was used to rank the WOMAC pain questions (activities) in order of affirmation as the pain score increased from 0. For each total WOMAC score category (0-20) we selected 25 individuals at random based on their maximum score across all visits. Fit to the Rasch model was assessed in this subset; stability of question ranking over successive visits was confirmed in the full OAI.
RESULTS: WOMAC data on 4,673 people were included, with 491 selected for subset analysis. The subset data showed good fit to the Rasch model (χ(2) = 43.31, P = 0.332). In the full OAI, the "using stairs" question was the first to score points as the total pain score increased from 0 (baseline logit score ± 95% confidence interval -4.74 ± 0.07), then "walking" (-2.94 ± 0.07), "standing" (-2.65 ± 0.07), "lying/sitting" (-2.00 ± 0.08), and finally "in bed" (-1.32 ± 0.09). This ordering was consistent over successive visits.
CONCLUSION: Knee pain is most likely to first appear during weight-bearing activities involving bending of the knee, such as using stairs. First appearance of this symptom may identify a group suitable for early intervention strategies.
BACKGROUND: Current evidence suggests limiting arthroscopic meniscectomy to those patients with no or early arthritis however outcomes of arthroscopic meniscectomy with patients of a higher body mass index (BMI) are not as widely available. The aim of this study was to determine if patient reported outcome scores for arthroscopic meniscectomy are adversely affected by the degree of knee osteoarthritis or patient BMI.
METHODS: All patients who underwent arthroscopic meniscectomy within the NHS in Scotland between the 6th of February and 29th of April 2012 were audited as part of the Scottish Government Musculoskeletal Audit and were eligible for inclusion within this study. A total of 270 patients returned both their pre-operative and post-operative EuroQol 5Q5D5L descriptive questionnaire and Knee injury and Osteoarthritis Outcomes Scores. Patients were stratified according to BMI, degree of osteoarthritis, history of injury, and duration of knee symptoms.
RESULTS: Pre-operative to post-operative EuroQol index scores [0.642±0.253 to 0.735±0.277, median±SD] and Knee injury and Osteoarthrtis Outcome Scores [44.63±18.78 to 62.28±24.94, median±SD] improved across all patients (p<0.0001). This was irrespective of degree of BMI, history of injury, or duration of symptoms. There was no such improvement in patients with moderate to severe osteoarthritis. Those patients with a BMI >35 kg/m2 had lower post-operative scores than the pre-operative scores of those of BMI <30 kg/m2.
CONCLUSIONS: Arthroscopic meniscectomy is beneficial regardless of patient BMI, duration of symptoms, history of injury, or in the presence of early osteoarthritis.
The synovium is an intra-articular mesenchymal tissue and essential for the normal joint function. It is involved in many pathological characteristic processes and sometimes specific for this distinctive tissue. In this study, we refer to synovial proliferative disorders according to the stage of osteoarthritis (OA) disease. Forty-three patients with knee OA were treated in the Department of Orthopedics and Traumatology, Emergency University Hospital of Bucharest, Romania, in the last two years. In all cases, we used at least five criteria for the knee OA: knee pain, knee joint tenderness, no palpable warmth over the knee, stiffness, erythrocyte sedimentation rate and C-reactive protein levels. In all the cases the synovial tissue was selected by the orthopedic surgeon. X-ray examination was taken in every case of the affected joint. Patients who were considered to have early OA underwent arthroscopic synovial biopsy of the symptomatic joint. Synovial tissue samples from patients with late OA were obtained at the time of knee joint arthroplasty. Microscopic examination in early osteoarthritis revealed for more than half of patients with synovial biopsy through arthroscopic technique having synovitis lesions with mononuclear infiltrates, diffuse fibrosis, thickening of the lining layer, macrophages appearance and neoformation vessels also. The synovitis seen in advanced OA knees tends to be diffuse and is not mandatory localized to areas of chondral defects, although an association has been reported between chondral defects and associated synovitis in the knee medial tibio-femoral compartment. The overexpression of mediators of inflammation and the increased mononuclear cell infiltration were seen in early OA, compared with late OA.
The saddle-shaped trapeziometacarpal (TMC) joint contributes importantly to the function of the human thumb. A balance between mobility and stability is essential in this joint, which experiences high loads and is prone to osteoarthritis (OA). Since instability is considered a risk factor for TMC OA, we assessed TMC joint instability during the execution of three isometric functional tasks (key pinch, jar grasp, and jar twist) in 76 patients with early TMC OA and 44 asymptomatic controls. Computed tomography images were acquired while subjects held their hands relaxed and while they applied 80% of their maximum effort for each task. Six degree-of-freedom rigid body kinematics of the metacarpal with respect to the trapezium from the unloaded to the loaded task positions were computed in terms of a TMC joint coordinate system. Joint instability was expressed as a function of the metacarpal translation and the applied force. We found that the TMC joint was more unstable during a key pinch task than during a jar grasp or a jar twist task. Sex, age, and early OA did not have an effect on TMC joint instability, suggesting that instability during these three tasks is not a predisposing factor in TMC OA.
PURPOSE: To assess the outcome of intra-articular platelet-rich plasma (PRP) injections into the knee in patients with early stages of osteoarthritis (OA) and to determine whether cyclical dosing would affect the end result.
METHODS: This is a prospective, randomized study in which 93 patients (119 knees) were followed up for a minimum of 2 years. Fifty knees were randomly selected prior to the first injection, to receive a second cycle at the completion of 1 year. A cycle consisted of three injections, each given at a monthly interval. The outcome was assessed using Knee Injury and Osteoarthritis Outcome Score (KOOS), Visual Analogue Scale (VAS), Tegner and Marx scoring systems, recorded prior to the first injection and then at 12, 18 and 24 months.
RESULTS: There was a significant improvement in all scores over time compared to the pre-treatment value (p < 0.001). At 12 months, both groups showed similar and significant improvement. At 18 months, except for KOOS (Symptoms) and Tegner score, all other parameters showed a significant difference between the two groups in favour of the patients who had received the second cycle (p < 0.001). At 2 years, the scores declined in both groups but remained above the pre-treatment value with no significant difference between the groups despite the patients with two cycles showing higher mean values for all the scores.
CONCLUSION: Intra-articular PRP injections into the knee for symptomatic early stages of OA are a valid treatment option. There is a significant reduction in pain and improvement in function after 12 months, which can be further improved at 18 months by annual repetition of the treatment. Although the beneficial effects are ill sustained at 2 years, the results are encouraging when compared to the pre-treatment function.
LEVEL OF EVIDENCE: II.
In adults, osteoarthritis (OA) is associated with obesity and knee alignment. Whether knee alignment differences develop during childhood and are associated with obesity is unknown. We assessed the distribution of knee alignment in children and adolescents, and determined how knee alignment differs between obese and nonobese children.
METHODS:
This cross-sectional study examined knee alignment in 155 healthy weight and 165 obese subjects. Knee alignment [metaphyseal-diaphyseal angle (MDA) and anterior tibiofemoral angle (ATFA)] and fat mass were measured using whole body dual-energy X-ray absorptiometry (DEXA). National reference data were used to generate age- and sex-specific body mass index (BMI, kg/m(2)) Z-scores. Multivariable linear regression was used to identify independent factors associated with ATFA and MDA.
RESULTS:
The mean MDA and ATFA were similar between obese and nonobese subjects. In stratified analyses, females had greater variability in MDA and ATFA values (p < 0.001 and p = 0.04, respectively) at higher BMI Z-scores. Compared with healthy weight controls, obese subjects had less valgus of the MDA prior to the onset of puberty (+ 2.0°, p = 0.001), but had greater valgus at later pubertal stages (-1.9°, p = 0.01).
CONCLUSION:
We found significantly greater variability in knee alignment among females at higher BMI Z-scores, and greater valgus alignment in obese adolescents in late puberty. The major limitation is the use of DEXA for assessment of alignment, which needs validation against longstanding radiographs. Longitudinal studies are needed to determine whether childhood obesity is a risk factor for progressive malalignment that may predispose to pain and risk of early osteoarthritis.
