Purpose:To assess the prevalence and degree of lumbosacral transitional vertebrae (LSTV) in the Osteoarthritis Initiative (OAI) cohort, to assess whether LSTV correlates with low back pain (LBP) and buttock pain, and to assess the reproducibility of grading LSTV. Materials & Methods:Institutional review board approval was obtained, and informed consent documentation was approved for the study protocol. Standard standing pelvic radiographs that included the transverse processes of L5 were graded according to Castellvi classification of LSTV in 4636 participants (1992 men and 2804 women; aged 45-80 years) from the OAI cohort. These data were correlated with prevalence and severity of LBP and buttock pain. Results:Prevalence of LSTV was 18.1% (841 of 4636), with a higher rate in men than in women (28.1% vs 11.1%, respectively; P , .001). Of the 841 individuals with LSTV, 41.72% were type I (dysplastic enlarged transverse process), 41.4% were type II (pseudoarticulation), 11.5% were type III (fusion), and 5.2% were type IV (one transverse process fused and one with pseudoarticulation). Of the participants without LSTV, 53.9% reported LBP, while the prevalence of LBP for types I, II, III, and IV was 46%, 73%, 40%, and 66%, respectively (P , .05, x 2 test). Types II and IV had higher prevalence and severity of LBP and buttock pain (P , .001).

Purpose To study the natural evolution of cartilage T2 relaxation times in knees with various extents of morphological cartilage abnormalities, assessed with 3T MRI from the Osteoarthritis Initiative. Materials and Methods Right knee MRIs of 245, 45–60 year old individuals without radiographic OA were included. Cartilage was segmented and T2 maps were generated in five compartments (patella, medial and lateral femoral condyle, medial and lateral tibia) at baseline and two-year follow-up. We examined the association of T2 values and two-year change of T2 values with various Whole-Organ MR Imaging Scores (WORMS). Statistical analysis was performed with ANOVA and Students t-tests. Results Higher baseline T2 was associated with more severe cartilage defects at baseline and subsequent cartilage loss (P<0.001). However, longitudinal T2 change was inversely associated with both baseline (P=0.038) and follow-up (P=0.002) severity of cartilage defects. Knees that developed new cartilage defects had smaller increases in T2 than subjects without defects (P=0.045). Individuals with higher baseline T2 showed smaller T2 increases over time (P<0.001). Conclusion An inverse correlation of longitudinal T2 changes versus baseline T2 values and morphological cartilage abnormalities suggests that once morphological cartilage defects occur, T2 values may be limited for evaluating further cartilage degradation.

Objective The purpose of this study was 1) to establish a gender- and BMI-specific reference database of cartilage T2 values, and 2) to assess the associations between cartilage T2 values and gender, age, and BMI in knees without radiographic osteoarthritis or MRI-based (WORMS 0/1) evidence of cartilage degeneration. Design 481 subjects between the ages of 45-65 years with Kellgren-Lawrence Scores 0/1 in the study knee were selected from the Osteoarthritis Initiative database. Baseline morphologic cartilage 3T MRI readings (WORMS scoring) and T2 measurements (resolution=0.313mmx0.446mm) were performed in the medial femur, lateral femur, medial tibia, lateral tibia, and patella compartments. In order to create a reference database, a logarithmic transformation was applied to the data to obtain the 5th-95th percentile values for T2. Results Significant differences in mean cartilage T2 values were observed between joint compartments. Although females had slightly higher T2 values than males in a majority of compartments, the differences were only significant in the medial femur (p<0.0001). A weak positive association was seen between age and T2 in all compartments, and was most pronounced in the patella (3.27% increase in median T2/10 years, p=0.009). Significant associations between BMI and T2 were observed, and were most pronounced in the lateral tibia (5.33% increase in median T2/5 kg/m2 increase in BMI, p<0.0001), and medial tibia (4.81% increase in median T2 /5 kg/m2 increase in BMI, p<0.0001). Conclusions This study established the first reference database of T2 values in a large sample of morphologically normal cartilage plates in knees without radiographic knee osteoarthritis. While cartilage T2 values were weakly associated with age and gender, they had the highest correlations with BMI.

Objective To investigate hip shape by active shape modeling (ASM) as a potential predictor of incident radiographic and symptomatic hip OA (rHOA and srHOA). Methods All hips developing rHOA from baseline (Kellgren-Lawrence [KL] grade 0/1) to mean 6 year follow up (KL ≥2, 190 hips), and 1:1 control hips (KLG 0/1 at both times, 192 hips) were included. Proximal femur shape was defined on baseline AP pelvis radiographs and submitted to ASM, producing a mean shape and continuous variables representing independent modes of shape variation. Mode scores (n=14, explaining 95% of shape variance) were simultaneously included in logistic regression models, with incident rHOA and srHOA as dependent variables, adjusted for intra-person correlations, sex, race, body mass index (BMI), baseline KL and/or symptoms. Results We evaluated 382 hips from 342 individuals: 61% women, 83% white, with mean age 62 years and BMI 29 kg/m2. Several modes differed by sex and race, but no modes were associated with incident rHOA overall. Among men only, modes 1 and 2 were significantly associated (for a 1-SD decrease in mode 1 score, OR 1.7 [95% CI 1.1, 2.5], and for a 1-SD increase in mode 2 score, OR 1.5 [95% CI 1.0, 2.2]) with incident rHOA. A 1-SD decrease in mode 2 or 3 score increased the odds of srHOA by 50%. Conclusion This study confirms other reports that variations in proximal femur shape have a modest association with incident hip OA. The observation of proximal femur shape associations with hip symptoms requires further investigation.

Disclosures of Conflicts of Interest: C.E.v.S. disclosed no relevant relationships. J.H.S. disclosed no relevant relationships. F.L. disclosed no relevant relationships. E.O. disclosed no relevant relationships. P.M.J. disclosed no relevant relationships. L.N. disclosed no relevant relationships. M.P. disclosed no relevant relationships. S.C.F. disclosed no relevant relationships. M.C.N. disclosed no relevant relationships. T.M.L. disclosed no relevant relationships. V.P. disclosed no relevant relationships.