- Email: [email protected]
Decreased proteoglycan composition in the articular cartilage of the lateral femoral condyle of the knee associates with decreased quality of life in individuals twelve months following anterior cruciate ligament reconstruction: A preliminary study
S286
Abstracts / Osteoarthritis and Cartilage 24 (2016) S63eS534
Methods: A total of 50 patients (mean age 57.0 years) who visited our out-patient clinic for knee pain between May 2012 and September 2015 were enrolled in this study. The severity of knee OA was classified by Kellgren-Lawrence (K/L) grading scale based on standing extendedknee X-ray images. All patients showed either K/L grade 0, 1 or 2, and were also performed 3TMRI for the affected knee. Diagnosis of knee OA for the subjects with K/L 0 and 1 was conducted using 3T MRI according to the method by Sharma et al (ARD 2013). Patients who showed less than 174 of femoro-tibial angle (FTA) were excluded from the study. MRI scan were performed using sagittal and coronal two dimensional (2D) fat suppressed and T2 weighted image fast spin-echo sequence (TR ¼ 5000 ms, TE¼ 70 ms, FOV 160 mm, matrix ¼ 384 307, Slice thickness ¼ 3 mm, turbo-factor ¼ 17, Flip-angle ¼ 150, scan time ¼ 3:00). The MRD distance were measured from the outer edge of medial tibial plateau to the medial edge of MM. T2 values of MM were obtained from T2 mapping technique, which were calculated from a five multi-echo, spin-echo sequence (TR: 1000 ms, TE: 13.8, 27.6, 41.4, 55.2 and 69.0 ms, slice thickness: 3 mm, FOV: 160 mm, matrix: 384 384, scan time: 3’30”). Inter relationships between the distance of MRD and the T2 values of MM were examined. Results: The patients showed the radiographic OA severities for K/L grade 0 (n ¼ 3), 1 (n ¼ 27) and 2 (n ¼ 20), respectively. Twenty-three of fifty patients were male, while remaining twenty-seven patients were female. No significant differences of FTA were observed between the patients with three different K/L grades. The T2 values of MM were associated with the MRDs in patients with early-stage of medial knee OA (r ¼ 0.39, p ¼ 0.004). When the patients were divided into four grades of the MRD according to the MRI Osteoarthritis Knee Score (MOAKS), no significant differences of the T2 values of MM between the patients with MOAKS grade 0, 1, and 2, respectively, were observed. However, the T2 values of MM in patients with grade 3 were significantly increased in comparison to those of MM in patients with grade 2 (25.1 vs. 21.7, p ¼0.003). When the patients were divided into two groups in terms of the MRD by the cutline of 3 mm, no association between the T2 values of MM and the MRD was observed in patients with less than 3 mm of MRD (r¼0.26, p¼0.18). However, the T2 values of MM were associated with the MRD in patients with 3 mm or more of MRD (r¼0.57, p¼0.004). Conclusions: The degeneration of MM was associated with MRD in patients with early-stage of medial knee OA. This association between the degeneration of MM and MRD becomes evident in the case of 3mm or more of MRD among those in early-stage of medial knee OA, suggesting the role of MRD for the one of the causal pathologies of the degeneration of MM in patients with early-stage knee OA. 475 COMPOSITIONAL CHANGES IN TIBIOFEMORAL CARTILAGE AFTER RUNNING AND BICYCLING A.A. Gatti y, M.D. Noseworthy y, P.W. Stratford y, E.C. Brenneman y, ~ a z, M.R. Maly y. y McMaster, Hamilton, ON, S. Totterman z, J. Tamez-Pen Canada; z Qmetrics, Rochester, NY, USA Purpose: Mechanical loading is necessary to maintain cartilage health. However, excessive loading may damage cartilage and lead to, or worsen, osteoarthritis (OA). Large loads associated with obesity are risk factors for OA. To combat obesity, OA, and other chronic diseases, physical activity is recommended. To properly prescribe physical activity, we must understand the in vivo response of knee cartilage to loading during activity. Magnetic resonance imaging (MRI) enables measurement of acute changes to cartilage morphology (size, shape) and composition (water, proteoglycan) in response to activity. Changes in cartilage morphology have been compared after different activity types; though, it is unclear whether load exposure between activities was equivalent in these studies. Studies of composition have used transverse relaxation time (T2) and have focused on running. The purpose of this study was to determine (1) whether running and bicycling change weight-bearing knee cartilage composition, measured using MRI T2 relaxation; and (2) whether there are different changes in T2 between running and bicycling of equal cumulative load. We hypothesized that (1) running and bicycling would acutely decrease T2; and (2) sustained loads during bicycling would cause greater acute changes in T2 than transitory high impact loads during running.
Methods: Fifteen healthy men (age 25.8þ/4.2y; height 1.79þ/ 0.06m; body mass 75.8þ/9.7kg) with healthy knees completed three study visits. Visit 1 was for biomechanical assessment and visits 2 and 3 were to obtain MR images preceding and following a bicycling and running activity. Biomechanical assessment was performed during running and bicycling to establish equivalent cumulative load exposures. To accomplish this, we recorded the vertical reaction force impulse of a step during running and pedal revolution during bicycling. Running data were collected for at least 5 successful trials using an in-ground force platform (OR6-7, AMTI, USA). Bicycling data were collected for a 5min bicycling bout using a bicycle pedal fitted with a bi-axial load-measuring device (Novatech, UK). These data were used to calculate the activity durations producing equivalent cumulative load exposures using Equation 1: CL ¼ R * I * t, where CL is the cumulative load of an activity, R is repetitions per minute, I is impulse per repetition and t is time (min). MR images were acquired using a 3-Tesla MR750 (GE Healthcare, USA) and an 8-channel transmit/receive knee coil. Two sequences were acquired before and after each activity; (1) sagittal multi-echo spin echo (MESE) to calculate T2 maps, and (2) 3D sagittal fat-saturated fast spoiled gradient recalled (FSPGR) for cartilage segmentation. T2 maps were created from MESE images, using Matlab (Mathworks, USA) by fitting pixel intensities from 8 echoes to Equation 2: STE¼ PD * e(-TE/T2) where STE is the measured signal, PD is the intercept (proton density), TE is the echo time (ms) and T2 the spin-spin relaxation time. FSPGR images were segmented into medial and lateral weight-bearing femoral, and medial and lateral tibial cartilage using a semi-automated atlas-based method (Qmetrics, USA). Segmentations were overlaid onto T2 maps and mean T2 calculated for each region. To answer research question one, analyses of variance (ANOVA) were used to determine if there was a main effect of activity on cartilage T2. To answer question two, T2 change (change ¼ pre-post) was used as the dependent variable in an ANOVA with activity, participant, and the interaction activity#participant as independent variables. Results: Running speeds ranged from 7.9 to 13.2km/h and bicycling power outputs ranged from 85 to 200W. The mean duration of running (14min 58s) and bicycling (46min 32s) were different (p<0.001), though the cumulative loads were not (p¼0.446). Bicycling produced no change (p¼0.462), while running shortened T2 (p¼0.002). Running was different than bicycling (Activity p¼0.017). No difference was noted based on participant (p¼0.236), however a significant interaction between activity and participant was found (p¼0.043). Conclusions: In our study on healthy men, running shortened T2 in tibiofemoral cartilage; while bicycling of an equivalent cumulative load did not. These results were contrary to our hypothesis that sustained loads during bicycling would cause greater changes in T2 through tissue creep. It is likely that another aspect of loading, such as peak force or loading rate drove the change in T2. Because knee cartilage tolerated bicycling with little change, future work should explore if bicycling is an ideal activity to combat obesity in knee OA. 476 DECREASED PROTEOGLYCAN COMPOSITION IN THE ARTICULAR CARTILAGE OF THE LATERAL FEMORAL CONDYLE OF THE KNEE ASSOCIATES WITH DECREASED QUALITY OF LIFE IN INDIVIDUALS TWELVE MONTHS FOLLOWING ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION: A PRELIMINARY STUDY B. Pietrosimone y, D. Nissman y, M. Harkey y, A. Creighton y, G. Kamath y, J. Blackburn y, D. Padua y, S.W. Marshall y, Y. Golightly y, A. Nelson y, K. Healy y, R. Schmitz z, J.B. Driban x, R. Loeser y, J.M. Jordan y, J. Spang y. y Univ. of North Carolina at Chapel Hill, Chapel Hill, NC, USA; z Univ. of North Carolina at Greensboro, Greensboro, NC, USA; x Tufts Univ. Med. Ctr., Boston, MA, USA Purpose: Approximately one-third of individuals that sustain an anterior cruciate ligament (ACL) injury develop radiographic osteoarthritis (OA) within a decade following injury. Early proteoglycan loss of articular cartilage, based on greater T1rho magnetic resonance imaging (MRI) relaxation times, has been detected as early as 12 months after an ACL reconstruction. These changes may be a biomarker that antedates radiographic OA. The cartilage in the lateral femoral condyle may be at high risk for early pre-radiographic changes as traumatic bone marrow edema-like lesions are common in the lateral tibiofemoral
Abstracts / Osteoarthritis and Cartilage 24 (2016) S63eS534
compartment due to forces that occur during the ACL injury. The purpose of this preliminary study was to determine if T1rho MRI markers of decreased articular cartilage proteoglycan density in the lateral femoral condyle of ACL injured knees were associated with knee-related quality of life (Knee Injury and Osteoarthritis Outcome Score Quality of Life subscale [KOOS QOL]) 12 months following ACL reconstruction. We hypothesized that individuals with greater T1rho MRI relaxation times would have poorer scores on the KOOS QOL. Methods: Twelve ACL injured patients, who were recruited into a longitudinal study, were evaluated 12 months following surgical ACL reconstruction (66% female, 21.0 ± 2.44 years old, 23.5± 2.5% body mass index). T1rho MRI relaxation times were collected bilaterally on a Siemens Magnetom TIM Trio 3T scanner. We used a T1rho prepared 3D FLASH sequence with a 500 Hz spin lock power and five different spin lock durations (40, 30, 20,10, 0 ms). A single investigator manually segmented the lateral femoral condyle articular cartilage (divided within the sagittal plane into five subsections which included: posterior, posterior meniscus, central, anterior meniscus and anterior subsections) using ITK-SNAP software. T1rho relaxation times from each subsection of the lateral femoral condyle in the ACL reconstructed knee were normalized to the same subsections in the contralateral limb creating a limb symmetry index (LSI ¼ ACL reconstructed limb/ contralateral limb) for each subsection. A LSI > 1.00 indicates less proteoglycan density in the ACL reconstructed limb compared to the contralateral limb. Participants completed the KOOS QOL subscale in a quiet room and were provided guidance on how to complete the instrument. Participants could choose one of five standard responses (scored 0 to 4) for each of the four questions on the KOOS QOL, and a normalized score was calculated for the subscale (0 ¼ poorest to 100 ¼ best KOOS QOL). Separate bivariate Pearson correlations (r) were conducted between the normally distributed outcomes of KOOS QOL score and T1rho relaxation time LSI from all five subsections of the lateral femoral condyle. Associations were classified as very weak (0.0e0.29), weak (0.3e0.5) moderate (0.5e0.69), strong (0.7e0.89), and very strong (0.9e1.0). The level of significance was set a priori at P 0.05 for all analyses. Results: Poorer KOOS QOL scores (mean: 68.8 ± 19.8) were strongly associated with increased T1rho relaxation time LSI ratios in the central subsection of the lateral tibiofemoral condyle (mean: 1.12±0.12, r¼ 0.71, P¼0.01). There were moderate (and not statistically significant) associations between higher T1rho relaxation time LSI ratios and poorer KOOS QOL were observed in the posterior meniscus (mean LSI¼1.11±0.16, r¼ - 0.51, P¼0.09) and anterior meniscus subsections (1.13±0.10, r¼ - 0.51, P¼0.09). Associations between T1rho relaxation time LSI ratios and KOOS QOL were weak/very weak for the anterior (1.07±0.08, r¼ - 0.29, P¼0.37) and posterior subsections (1.13±0.21, r¼ 0.1, P¼0.76). Conclusions: The LSI scores greater than 1.00 that indicate, on average, T1rho relaxation times were greater in all five lateral femoral condyle subsections of the ACL reconstructed limb compared to the contralateral limb in our sample. In this small study, individuals with decreased proteoglycan composition in the central portion of the lateral femoral condyle of the ACL reconstructed limb reported a poorer knee-related KOOS QOL. These data suggest that cartilage health in the lateral femoral condyle is associated with knee-related QOL as early as 12-months following injury. Future research will seek to determine to what extent the association between T1rho relaxation times and knee-related QOL is influenced by other mechanical or metabolic factors. Furthermore, future study should determine if the early associations between T1rho relaxation times and knee-related QOL are indicative of factors related to the early development of posttraumatic OA. 477 ASSOCIATIONS BETWEEN MAGNETIC RESONANCE IMAGINGDEFINED STRUCTURAL PATHOLOGIES AND GENERALIZED AND LOCALIZED KNEE PAIN e THE OULU KNEE OSTEOARTHRITIS STUDY x, A. Guermazi k, J. Niinima €ki x, ¶, P. Kaukinen y, z, J. Podlipska P. Lehenkari #, yy, F.W. Roemer k, zz, M.T. Nieminen x, xx, J.M. Koski kk, J.P. Arokoski y, z, S. Saarakkala x, ¶. y Inst. of Clinical Med., Univ. of Eastern
S287
Finland, Kuopio, Finland; z Dept. of Physical and Rehabilitation Med., Kuopio Univ. Hosp., Kuopio, Finland; x Res. Unit of Med. Imaging, Physics and Technology, Univ. of Oulu, Oulu, Finland; k Quantitative Imaging Ctr., Dept. of Radiology, Boston Univ. School of Med., Boston, MA; ¶ Dept. of Diagnostic Radiology, Oulu Univ. Hosp., Oulu, Finland; # Dept. of Anatomy, Univ. of Oulu, Oulu, Finland; yy Dept. of Surgery, Med. Res. Ctr., Oulu Univ. Hosp., Oulu, Finland; zz Dept. of Radiology, Univ. of ErlangenNuremberg, Erlangen, Germany; xx Med. Res. Ctr., Univ. of Oulu and Oulu Univ. Hosp., Oulu, Finland; kk Dept. of Internal Med., Mikkeli Central Hosp., Mikkeli, Finland Purpose: Pain is the predominant symptom of osteoarthritis (OA) but its exact source remains unclear. Magnetic resonance imaging (MRI) is increasingly important to understand the role of the different joint tissues involved in OA symptoms and disease progression. The assessment of pain location and pain characteristics might give additional insights regarding different joint tissues associated with pain. Increasing pain intensity and disability are both found to be associated with diffuse pain. Generalized pain is more likely to occur in subjects with moderate to severe disease on plain radiographs. However, the associations between the location of structural changes in MRI and knee pain localization has not been reported so far. There were two aims in our study: First, we evaluated the associations between the presence of knee pain and multi-feature structural pathology assessed using MRI. Second, we investigated the associations between the locations of structural changes and different knee pain patterns. Methods: This study is part of the Oulu Knee OA (OKOA) study, from which 80 symptomatic subjects (age 59.9±7.8 years, female n¼49 (61.3%)) with knee pain and suspicion or diagnosis of knee OA and 63 asymptomatic subjects (age 54.6±14.1 years, female n¼38 (60.3%)) were included. All subjects underwent knee MRI. Severity of structural changes was graded by MRI Osteoarthritis Knee Score (MOAKS) in separate knee locations. Knee pain location was assessed using photographs of the knee on which each subject had marked the location(s) of pain. Knee pain locations were analyzed by placing a transparent template with modified knee pain map over the image, and finally the pain map findings were divided into five patterns (medial, lateral, patellar, posterior and diffuse pain). The associations between cartilage damage, bone marrow lesions, osteophytes, Hoffa’s synovitis, effusionsynovitis, meniscal damage and structural pathologies in ligaments, tendons and bursae and both the presence of pain and the knee pain patterns were assessed. Results: The presence of Hoffa’s synovitis (adjusted OR 4.2, 95% CI 1.7e10.5) and osteophytes in general (5.8, 2.1e16.5) and in the patellofemoral joint (6.7, 2.3e19.6)), in medial tibia (4.2, 1.6e11.0) and femur (5.8, 2.2e15.1) and in lateral femur (12.9, 3.2e51.9) was significantly associated with the presence of pain. The ORs for knee pain locations are presented in Table 1. Any Hoffa’s synovitis was associated with patellar pain (adjusted OR 6.2, 95% CI 1.6e32.5) and moderate-to-severe Hoffa’s synovitis (Figure 1.) with diffuse pain (4.0, 1.0e15.9). Medial knee pain was associated with cartilage loss in the medial tibia (adjusted OR 3.7, 95% CI 1.2e11.9), osteophytes in the medial tibia (3.6, 1.1e11.7) and medial femur (3.3, 1.1e10.2), medial meniscal maceration (3.2, 1.0e9.9) and anterior meniscal extrusions (4.1, 1.2e14.0). Diffuse pain was reported by subjects with BMLs in lateral tibia (adjusted OR 3.8, 95% CI 1.1e12.9) and osteophytes in lateral tibia (5.4, 1.6e18.2), lateral femur (3.7, 1.2e11.3) and medial femur (3.3, 1.1e9.6) and subjects with large BMLs (4.2, 1.0e18.8) and osteophytes (3.7, 1.1e12.9) in patellofemoral region and by subjects with patellar tendon signal abnormalities (8.6, 1.5e50.5). Conclusions: We found that Hoffa’s synovitis and osteophytes were strongly associated with the presence of knee pain. Subjects with mild to severe Hoffa’s synovitis reported increased odds for patellar pain and subjects with severe Hoffa’s synovitis for diffuse pain. Medially located pain was associated most often with structural pathologies in the medial tibia and/or medial femur while laterally located and patellofemoral structural pathologies showed associations with diffuse pain. More studies are warranted to better understand the heterogeneous nature of both pain experience and the relationship between pain and structural pathologies detected in MRI.
Abstracts / Osteoarthritis and Cartilage 24 (2016) S63eS534
Methods: A total of 50 patients (mean age 57.0 years) who visited our out-patient clinic for knee pain between May 2012 and September 2015 were enrolled in this study. The severity of knee OA was classified by Kellgren-Lawrence (K/L) grading scale based on standing extendedknee X-ray images. All patients showed either K/L grade 0, 1 or 2, and were also performed 3TMRI for the affected knee. Diagnosis of knee OA for the subjects with K/L 0 and 1 was conducted using 3T MRI according to the method by Sharma et al (ARD 2013). Patients who showed less than 174 of femoro-tibial angle (FTA) were excluded from the study. MRI scan were performed using sagittal and coronal two dimensional (2D) fat suppressed and T2 weighted image fast spin-echo sequence (TR ¼ 5000 ms, TE¼ 70 ms, FOV 160 mm, matrix ¼ 384 307, Slice thickness ¼ 3 mm, turbo-factor ¼ 17, Flip-angle ¼ 150, scan time ¼ 3:00). The MRD distance were measured from the outer edge of medial tibial plateau to the medial edge of MM. T2 values of MM were obtained from T2 mapping technique, which were calculated from a five multi-echo, spin-echo sequence (TR: 1000 ms, TE: 13.8, 27.6, 41.4, 55.2 and 69.0 ms, slice thickness: 3 mm, FOV: 160 mm, matrix: 384 384, scan time: 3’30”). Inter relationships between the distance of MRD and the T2 values of MM were examined. Results: The patients showed the radiographic OA severities for K/L grade 0 (n ¼ 3), 1 (n ¼ 27) and 2 (n ¼ 20), respectively. Twenty-three of fifty patients were male, while remaining twenty-seven patients were female. No significant differences of FTA were observed between the patients with three different K/L grades. The T2 values of MM were associated with the MRDs in patients with early-stage of medial knee OA (r ¼ 0.39, p ¼ 0.004). When the patients were divided into four grades of the MRD according to the MRI Osteoarthritis Knee Score (MOAKS), no significant differences of the T2 values of MM between the patients with MOAKS grade 0, 1, and 2, respectively, were observed. However, the T2 values of MM in patients with grade 3 were significantly increased in comparison to those of MM in patients with grade 2 (25.1 vs. 21.7, p ¼0.003). When the patients were divided into two groups in terms of the MRD by the cutline of 3 mm, no association between the T2 values of MM and the MRD was observed in patients with less than 3 mm of MRD (r¼0.26, p¼0.18). However, the T2 values of MM were associated with the MRD in patients with 3 mm or more of MRD (r¼0.57, p¼0.004). Conclusions: The degeneration of MM was associated with MRD in patients with early-stage of medial knee OA. This association between the degeneration of MM and MRD becomes evident in the case of 3mm or more of MRD among those in early-stage of medial knee OA, suggesting the role of MRD for the one of the causal pathologies of the degeneration of MM in patients with early-stage knee OA. 475 COMPOSITIONAL CHANGES IN TIBIOFEMORAL CARTILAGE AFTER RUNNING AND BICYCLING A.A. Gatti y, M.D. Noseworthy y, P.W. Stratford y, E.C. Brenneman y, ~ a z, M.R. Maly y. y McMaster, Hamilton, ON, S. Totterman z, J. Tamez-Pen Canada; z Qmetrics, Rochester, NY, USA Purpose: Mechanical loading is necessary to maintain cartilage health. However, excessive loading may damage cartilage and lead to, or worsen, osteoarthritis (OA). Large loads associated with obesity are risk factors for OA. To combat obesity, OA, and other chronic diseases, physical activity is recommended. To properly prescribe physical activity, we must understand the in vivo response of knee cartilage to loading during activity. Magnetic resonance imaging (MRI) enables measurement of acute changes to cartilage morphology (size, shape) and composition (water, proteoglycan) in response to activity. Changes in cartilage morphology have been compared after different activity types; though, it is unclear whether load exposure between activities was equivalent in these studies. Studies of composition have used transverse relaxation time (T2) and have focused on running. The purpose of this study was to determine (1) whether running and bicycling change weight-bearing knee cartilage composition, measured using MRI T2 relaxation; and (2) whether there are different changes in T2 between running and bicycling of equal cumulative load. We hypothesized that (1) running and bicycling would acutely decrease T2; and (2) sustained loads during bicycling would cause greater acute changes in T2 than transitory high impact loads during running.
Methods: Fifteen healthy men (age 25.8þ/4.2y; height 1.79þ/ 0.06m; body mass 75.8þ/9.7kg) with healthy knees completed three study visits. Visit 1 was for biomechanical assessment and visits 2 and 3 were to obtain MR images preceding and following a bicycling and running activity. Biomechanical assessment was performed during running and bicycling to establish equivalent cumulative load exposures. To accomplish this, we recorded the vertical reaction force impulse of a step during running and pedal revolution during bicycling. Running data were collected for at least 5 successful trials using an in-ground force platform (OR6-7, AMTI, USA). Bicycling data were collected for a 5min bicycling bout using a bicycle pedal fitted with a bi-axial load-measuring device (Novatech, UK). These data were used to calculate the activity durations producing equivalent cumulative load exposures using Equation 1: CL ¼ R * I * t, where CL is the cumulative load of an activity, R is repetitions per minute, I is impulse per repetition and t is time (min). MR images were acquired using a 3-Tesla MR750 (GE Healthcare, USA) and an 8-channel transmit/receive knee coil. Two sequences were acquired before and after each activity; (1) sagittal multi-echo spin echo (MESE) to calculate T2 maps, and (2) 3D sagittal fat-saturated fast spoiled gradient recalled (FSPGR) for cartilage segmentation. T2 maps were created from MESE images, using Matlab (Mathworks, USA) by fitting pixel intensities from 8 echoes to Equation 2: STE¼ PD * e(-TE/T2) where STE is the measured signal, PD is the intercept (proton density), TE is the echo time (ms) and T2 the spin-spin relaxation time. FSPGR images were segmented into medial and lateral weight-bearing femoral, and medial and lateral tibial cartilage using a semi-automated atlas-based method (Qmetrics, USA). Segmentations were overlaid onto T2 maps and mean T2 calculated for each region. To answer research question one, analyses of variance (ANOVA) were used to determine if there was a main effect of activity on cartilage T2. To answer question two, T2 change (change ¼ pre-post) was used as the dependent variable in an ANOVA with activity, participant, and the interaction activity#participant as independent variables. Results: Running speeds ranged from 7.9 to 13.2km/h and bicycling power outputs ranged from 85 to 200W. The mean duration of running (14min 58s) and bicycling (46min 32s) were different (p<0.001), though the cumulative loads were not (p¼0.446). Bicycling produced no change (p¼0.462), while running shortened T2 (p¼0.002). Running was different than bicycling (Activity p¼0.017). No difference was noted based on participant (p¼0.236), however a significant interaction between activity and participant was found (p¼0.043). Conclusions: In our study on healthy men, running shortened T2 in tibiofemoral cartilage; while bicycling of an equivalent cumulative load did not. These results were contrary to our hypothesis that sustained loads during bicycling would cause greater changes in T2 through tissue creep. It is likely that another aspect of loading, such as peak force or loading rate drove the change in T2. Because knee cartilage tolerated bicycling with little change, future work should explore if bicycling is an ideal activity to combat obesity in knee OA. 476 DECREASED PROTEOGLYCAN COMPOSITION IN THE ARTICULAR CARTILAGE OF THE LATERAL FEMORAL CONDYLE OF THE KNEE ASSOCIATES WITH DECREASED QUALITY OF LIFE IN INDIVIDUALS TWELVE MONTHS FOLLOWING ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION: A PRELIMINARY STUDY B. Pietrosimone y, D. Nissman y, M. Harkey y, A. Creighton y, G. Kamath y, J. Blackburn y, D. Padua y, S.W. Marshall y, Y. Golightly y, A. Nelson y, K. Healy y, R. Schmitz z, J.B. Driban x, R. Loeser y, J.M. Jordan y, J. Spang y. y Univ. of North Carolina at Chapel Hill, Chapel Hill, NC, USA; z Univ. of North Carolina at Greensboro, Greensboro, NC, USA; x Tufts Univ. Med. Ctr., Boston, MA, USA Purpose: Approximately one-third of individuals that sustain an anterior cruciate ligament (ACL) injury develop radiographic osteoarthritis (OA) within a decade following injury. Early proteoglycan loss of articular cartilage, based on greater T1rho magnetic resonance imaging (MRI) relaxation times, has been detected as early as 12 months after an ACL reconstruction. These changes may be a biomarker that antedates radiographic OA. The cartilage in the lateral femoral condyle may be at high risk for early pre-radiographic changes as traumatic bone marrow edema-like lesions are common in the lateral tibiofemoral
Abstracts / Osteoarthritis and Cartilage 24 (2016) S63eS534
compartment due to forces that occur during the ACL injury. The purpose of this preliminary study was to determine if T1rho MRI markers of decreased articular cartilage proteoglycan density in the lateral femoral condyle of ACL injured knees were associated with knee-related quality of life (Knee Injury and Osteoarthritis Outcome Score Quality of Life subscale [KOOS QOL]) 12 months following ACL reconstruction. We hypothesized that individuals with greater T1rho MRI relaxation times would have poorer scores on the KOOS QOL. Methods: Twelve ACL injured patients, who were recruited into a longitudinal study, were evaluated 12 months following surgical ACL reconstruction (66% female, 21.0 ± 2.44 years old, 23.5± 2.5% body mass index). T1rho MRI relaxation times were collected bilaterally on a Siemens Magnetom TIM Trio 3T scanner. We used a T1rho prepared 3D FLASH sequence with a 500 Hz spin lock power and five different spin lock durations (40, 30, 20,10, 0 ms). A single investigator manually segmented the lateral femoral condyle articular cartilage (divided within the sagittal plane into five subsections which included: posterior, posterior meniscus, central, anterior meniscus and anterior subsections) using ITK-SNAP software. T1rho relaxation times from each subsection of the lateral femoral condyle in the ACL reconstructed knee were normalized to the same subsections in the contralateral limb creating a limb symmetry index (LSI ¼ ACL reconstructed limb/ contralateral limb) for each subsection. A LSI > 1.00 indicates less proteoglycan density in the ACL reconstructed limb compared to the contralateral limb. Participants completed the KOOS QOL subscale in a quiet room and were provided guidance on how to complete the instrument. Participants could choose one of five standard responses (scored 0 to 4) for each of the four questions on the KOOS QOL, and a normalized score was calculated for the subscale (0 ¼ poorest to 100 ¼ best KOOS QOL). Separate bivariate Pearson correlations (r) were conducted between the normally distributed outcomes of KOOS QOL score and T1rho relaxation time LSI from all five subsections of the lateral femoral condyle. Associations were classified as very weak (0.0e0.29), weak (0.3e0.5) moderate (0.5e0.69), strong (0.7e0.89), and very strong (0.9e1.0). The level of significance was set a priori at P 0.05 for all analyses. Results: Poorer KOOS QOL scores (mean: 68.8 ± 19.8) were strongly associated with increased T1rho relaxation time LSI ratios in the central subsection of the lateral tibiofemoral condyle (mean: 1.12±0.12, r¼ 0.71, P¼0.01). There were moderate (and not statistically significant) associations between higher T1rho relaxation time LSI ratios and poorer KOOS QOL were observed in the posterior meniscus (mean LSI¼1.11±0.16, r¼ - 0.51, P¼0.09) and anterior meniscus subsections (1.13±0.10, r¼ - 0.51, P¼0.09). Associations between T1rho relaxation time LSI ratios and KOOS QOL were weak/very weak for the anterior (1.07±0.08, r¼ - 0.29, P¼0.37) and posterior subsections (1.13±0.21, r¼ 0.1, P¼0.76). Conclusions: The LSI scores greater than 1.00 that indicate, on average, T1rho relaxation times were greater in all five lateral femoral condyle subsections of the ACL reconstructed limb compared to the contralateral limb in our sample. In this small study, individuals with decreased proteoglycan composition in the central portion of the lateral femoral condyle of the ACL reconstructed limb reported a poorer knee-related KOOS QOL. These data suggest that cartilage health in the lateral femoral condyle is associated with knee-related QOL as early as 12-months following injury. Future research will seek to determine to what extent the association between T1rho relaxation times and knee-related QOL is influenced by other mechanical or metabolic factors. Furthermore, future study should determine if the early associations between T1rho relaxation times and knee-related QOL are indicative of factors related to the early development of posttraumatic OA. 477 ASSOCIATIONS BETWEEN MAGNETIC RESONANCE IMAGINGDEFINED STRUCTURAL PATHOLOGIES AND GENERALIZED AND LOCALIZED KNEE PAIN e THE OULU KNEE OSTEOARTHRITIS STUDY x, A. Guermazi k, J. Niinima €ki x, ¶, P. Kaukinen y, z, J. Podlipska P. Lehenkari #, yy, F.W. Roemer k, zz, M.T. Nieminen x, xx, J.M. Koski kk, J.P. Arokoski y, z, S. Saarakkala x, ¶. y Inst. of Clinical Med., Univ. of Eastern
S287
Finland, Kuopio, Finland; z Dept. of Physical and Rehabilitation Med., Kuopio Univ. Hosp., Kuopio, Finland; x Res. Unit of Med. Imaging, Physics and Technology, Univ. of Oulu, Oulu, Finland; k Quantitative Imaging Ctr., Dept. of Radiology, Boston Univ. School of Med., Boston, MA; ¶ Dept. of Diagnostic Radiology, Oulu Univ. Hosp., Oulu, Finland; # Dept. of Anatomy, Univ. of Oulu, Oulu, Finland; yy Dept. of Surgery, Med. Res. Ctr., Oulu Univ. Hosp., Oulu, Finland; zz Dept. of Radiology, Univ. of ErlangenNuremberg, Erlangen, Germany; xx Med. Res. Ctr., Univ. of Oulu and Oulu Univ. Hosp., Oulu, Finland; kk Dept. of Internal Med., Mikkeli Central Hosp., Mikkeli, Finland Purpose: Pain is the predominant symptom of osteoarthritis (OA) but its exact source remains unclear. Magnetic resonance imaging (MRI) is increasingly important to understand the role of the different joint tissues involved in OA symptoms and disease progression. The assessment of pain location and pain characteristics might give additional insights regarding different joint tissues associated with pain. Increasing pain intensity and disability are both found to be associated with diffuse pain. Generalized pain is more likely to occur in subjects with moderate to severe disease on plain radiographs. However, the associations between the location of structural changes in MRI and knee pain localization has not been reported so far. There were two aims in our study: First, we evaluated the associations between the presence of knee pain and multi-feature structural pathology assessed using MRI. Second, we investigated the associations between the locations of structural changes and different knee pain patterns. Methods: This study is part of the Oulu Knee OA (OKOA) study, from which 80 symptomatic subjects (age 59.9±7.8 years, female n¼49 (61.3%)) with knee pain and suspicion or diagnosis of knee OA and 63 asymptomatic subjects (age 54.6±14.1 years, female n¼38 (60.3%)) were included. All subjects underwent knee MRI. Severity of structural changes was graded by MRI Osteoarthritis Knee Score (MOAKS) in separate knee locations. Knee pain location was assessed using photographs of the knee on which each subject had marked the location(s) of pain. Knee pain locations were analyzed by placing a transparent template with modified knee pain map over the image, and finally the pain map findings were divided into five patterns (medial, lateral, patellar, posterior and diffuse pain). The associations between cartilage damage, bone marrow lesions, osteophytes, Hoffa’s synovitis, effusionsynovitis, meniscal damage and structural pathologies in ligaments, tendons and bursae and both the presence of pain and the knee pain patterns were assessed. Results: The presence of Hoffa’s synovitis (adjusted OR 4.2, 95% CI 1.7e10.5) and osteophytes in general (5.8, 2.1e16.5) and in the patellofemoral joint (6.7, 2.3e19.6)), in medial tibia (4.2, 1.6e11.0) and femur (5.8, 2.2e15.1) and in lateral femur (12.9, 3.2e51.9) was significantly associated with the presence of pain. The ORs for knee pain locations are presented in Table 1. Any Hoffa’s synovitis was associated with patellar pain (adjusted OR 6.2, 95% CI 1.6e32.5) and moderate-to-severe Hoffa’s synovitis (Figure 1.) with diffuse pain (4.0, 1.0e15.9). Medial knee pain was associated with cartilage loss in the medial tibia (adjusted OR 3.7, 95% CI 1.2e11.9), osteophytes in the medial tibia (3.6, 1.1e11.7) and medial femur (3.3, 1.1e10.2), medial meniscal maceration (3.2, 1.0e9.9) and anterior meniscal extrusions (4.1, 1.2e14.0). Diffuse pain was reported by subjects with BMLs in lateral tibia (adjusted OR 3.8, 95% CI 1.1e12.9) and osteophytes in lateral tibia (5.4, 1.6e18.2), lateral femur (3.7, 1.2e11.3) and medial femur (3.3, 1.1e9.6) and subjects with large BMLs (4.2, 1.0e18.8) and osteophytes (3.7, 1.1e12.9) in patellofemoral region and by subjects with patellar tendon signal abnormalities (8.6, 1.5e50.5). Conclusions: We found that Hoffa’s synovitis and osteophytes were strongly associated with the presence of knee pain. Subjects with mild to severe Hoffa’s synovitis reported increased odds for patellar pain and subjects with severe Hoffa’s synovitis for diffuse pain. Medially located pain was associated most often with structural pathologies in the medial tibia and/or medial femur while laterally located and patellofemoral structural pathologies showed associations with diffuse pain. More studies are warranted to better understand the heterogeneous nature of both pain experience and the relationship between pain and structural pathologies detected in MRI.