Ligamentum teres lesions are associated with compositional and structural hip cartilage degenerative change: region-specific cartilage degeneration.

OBJECTIVES: To investigate the association between magnetic resonance imaging (MRI)-based ligamentum teres lesions (LTL) and structural hip degeneration. METHODS: Bilateral 3-T hip MRIs of participants (n = 93 [36 men]; mean age ( ± SD) 51 years ± 15.4) recruited from the community and the orthopedic clinic of a single medical center were included. Clinical and imaging data acquired included hip disability and osteoarthritis outcome scores, semi-quantitative scoring of hip osteoarthritis on MRI (SHOMRI) scores on fluid-sensitive sequences, and cartilage T1ρ/T2 compositional sequences. An MRI-based LTL scoring system, incorporating continuity, thickening, and signal intensity, ranging from 0 (normal) to 4 (complete tear) was constructed. Hip morphological features associated with LTL, based on functional or anatomical relationships to LT, were defined. Relationships between MRI-LT scores and SHOMRI, global/regional cartilage T1ρ/T2, and proposed morphological abnormalities and LTL were explored by mixed effects linear and logistic regression models. RESULTS: In 82 (46.1%) hips, no pain was documented; 118 (63.4%) and 68 (36.6%) hips were graded as KL-grade ≤ 1 and ≥ 2, respectively. Compared to MRI-LT score = 0 (normal), score = 4 (complete tear) revealed significantly worse subchondral bony degenerative changes for bone marrow lesions (SHOMRI-BML) and subchondral cysts (SHOMRI-sc) (p < 0.001, p = 0.015, respectively). Global acetabular T1ρ, femoral T2 were significantly increased for abnormal MRI-LT scores (p-range = 0.005-0.032). Regional analyses revealed significantly increased T1ρ/T2 in central acetabular/increased T2 in off-central femoral regions (p-range = 0.005-0.046). Pulvinar effusion-synovitis, shallow fovea, and foveal osteophytes were significantly associated with abnormal LT MRI findings (p-range = < 0.001-0.044). CONCLUSION: MRI abnormalities of LT are associated with worse SHOMRI-sc/BML scores, indicative of hip osteoarthritis and higher T1ρ and T2 that differ by region. Pulvinar effusion-synovitis and changes in femoral head morphology are associated with LTL. CLINICAL RELEVANCE STATEMENT: Abnormal ligamentum teres findings identified via MRI are associated with structural degenerative changes of the hip joint and alterations in acetabular and femoral cartilage compositions show spatial differences in relation to LTL. KEY POINTS: The clinical significance of common ligamentum teres lesions (LTL) on MRI is not well understood. LTL identified by an MRI-based scoring system is associated with worse biomarkers, indicating more advanced degenerative hip changes. Effusion-synovitis signal at pulvinar, shallow fovea capitis, and foveal osteophytes are associated with LTL on imaging.

Thigh muscle and fat volumes are associated with knee cartilage abnormalities and bone marrow edema-like lesions: data from the osteoarthritis initiative.

OBJECTIVE: To investigate the associations of thigh muscle and fat volumes with structural abnormalities on MRI related to knee osteoarthritis. MATERIALS AND METHODS: MRI studies of the thighs and knees from 100 individuals were randomly selected from the Osteoarthritis Initiative Cohort. Whole Organ MR Scoring (WORMS) and effusion-synovitis scoring were performed in all knee MRI. Thigh muscles, intermuscular fat, and subcutaneous fat were manually segmented in 15 consecutive MR thigh images. Radiographic Kellgren-Lawrence grades (KLG) were also obtained in all knee radiographs. Independent t-tests were used to investigate the associations between thigh muscle and fat volumes, and sex. Mixed-effects analyses were obtained to investigate the associations between thigh muscle and fat volumes, KLG, WOMAC pain score, cartilage and bone marrow WORMS, as well as effusion-synovitis scores. RESULTS: Women had higher subcutaneous fat volume than men (616.82 vs. 229.13 cm3, p < 0.01) and men had higher muscle volumes than women (p < 0.01). Quadriceps (coef = -2.15, p = 0.01) and vastus medialis (coef = -1.84, p = 0.03) volumes were negatively associated with the WORMS cartilage scores. Intermuscular fat volume (coef = 0.48, p = 0.01) was positively associated with WORMS bone marrow edema-like lesion (BMEL) scores. The quadriceps (coef = -0.99, p < 0.01) and hamstring (coef = -0.59, p = 0.01) volumes were negatively associated with WORMS BMEL scores. No evidence of an association was found between thigh muscle and fat volumes with KLG and effusion-synovitis grading (p > 0.05). CONCLUSION: Increased quadriceps and hamstring volumes were negatively associated with cartilage lesion and BMEL scores while no evidence of an association was found between thigh muscle and fat volumes, and radiographic knee osteoarthritis or effusion-synovitis grading.

MR imaging after patellar MACI and MPFL reconstruction: a comparison of isolated versus combined procedures.

OBJECTIVE: To qualitatively and quantitatively evaluate the 2.5-year MRI outcome after Matrix-associated autologous chondrocyte implantation (MACI) at the patella, reconstruction of the medial patellofemoral ligament (MPFL), and combined procedures. METHODS: In 66 consecutive patients (age 22.8 ± 6.4years) with MACI at the patella (n = 16), MPFL reconstruction (MPFL; n = 31), or combined procedures (n = 19) 3T MRI was performed 2.5 years after surgery. For morphological MRI evaluation WORMS and MOCART scores were obtained. In addition quantitative cartilage T2 and T1rho relaxation times were acquired. Several clinical scores were obtained. Statistical analyses included descriptive statistics, Mann-Whitney-U-tests and Pearson correlations. RESULTS: WORMS scores at follow-up (FU) were significantly worse after combined procedures (8.7 ± 4.9) than after isolated MACI (4.3 ± 3.6, P = 0.005) and after isolated MPFL reconstruction (5.3 ± 5.7, P = 0.004). Bone marrow edema at the patella in the combined group was the only (non-significantly) worsening WORMS parameter from pre- to postoperatively. MOCART scores were significantly worse in the combined group than in the isolated MACI group (57 ± 3 vs 88 ± 9, P < 0.001). Perfect defect filling was achieved in 26% and 69% of cases in the combined and MACI group, respectively (P = 0.031). Global and patellar T2 values were higher in the combined group (Global T2: 34.0 ± 2.8ms) and MACI group (35.5 ± 3.1ms) as compared to the MPFL group (31.1 ± 3.2ms, P < 0.05). T2 values correlated significantly with clinical scores (P < 0.005). Clinical Cincinnati scores were significantly worse in the combined group (P < 0.05). CONCLUSION: After combined surgery with patellar MACI and MPFL reconstruction inferior MRI outcomes were observed than after isolated procedures. Therefore, patients with need for combined surgery may be at particular risk for osteoarthritis.

The effect of DPP-4 inhibition with sitagliptin on incretin secretion and on fasting and postprandial glucose turnover in subjects with impaired fasting glucose.

OBJECTIVE: Low glucagon-like peptide-1 (GLP-1) concentrations have been observed in impaired fasting glucose (IFG). It is uncertain whether these abnormalities contribute directly to the pathogenesis of IFG and impaired glucose tolerance. Dipeptidyl peptidase-4 (DPP-4) inhibitors raise incretin hormone concentrations enabling an examination of their effects on glucose turnover in IFG. RESEARCH DESIGN AND METHODS: We studied 22 subjects with IFG using a double-blinded, placebo-controlled, parallel-group design. At the time of enrollment, subjects ate a standardized meal labelled with [1-(13)C]-glucose. Infused [6-(3)H] glucose enabled measurement of systemic meal appearance (MRa). Infused [6,6-(2)H(2)] glucose enabled measurement of endogenous glucose production (EGP) and glucose disappearance (Rd). Subsequently, subjects were randomized to 100 mg of sitagliptin daily or placebo. After an 8-week treatment period, the mixed meal was repeated. RESULTS: As expected, subjects with IFG who received placebo did not experience any change in glucose concentrations. Despite raising intact GLP-1 concentrations, treatment with sitagliptin did not alter either fasting or postprandial glucose, insulin or C-peptide concentrations. Postprandial EGP (18.1 +/- 0.7 vs 17.6 +/- 0.8 micromol/kg per min, P = 0.53), Rd (55.6 +/- 4.3 vs 58.9 +/- 3.3 micromol/kg per min, P = 0.47) and MRa (6639 +/- 377 vs 6581 +/- 316 micromol/kg per 6 h, P = 0.85) were unchanged. Sitagliptin was associated with decreased total GLP-1 implying decreased incretin secretion. CONCLUSIONS: DPP-4 inhibition did not alter fasting or postprandial glucose turnover in people with IFG. Low incretin concentrations are unlikely to be involved in the pathogenesis of IFG.

Effects of dipeptidyl peptidase-4 inhibition on gastrointestinal function, meal appearance, and glucose metabolism in type 2 diabetes.

OBJECTIVE: We sought to determine whether alterations in meal absorption and gastric emptying contribute to the mechanism by which inhibitors of dipeptidyl peptidase-4 (DPP-4) lower postprandial glucose concentrations. RESEARCH DESIGN AND METHODS: We simultaneously measured gastric emptying, meal appearance, endogenous glucose production, and glucose disappearance in 14 subjects with type 2 diabetes treated with either vildaglipitin (50 mg b.i.d.) or placebo for 10 days using a double-blind, placebo-controlled, randomized, crossover design. RESULTS: Fasting (7.3 +/- 0.5 vs. 7.9 +/- 0.5 mmol/l) and peak postprandial (14.1 +/- 0.6 vs. 15.9 +/- 0.9 mmol/l) glucose concentrations were lower (P < 0.01) after vildagliptin treatment than placebo. Despite lower glucose concentrations, postprandial insulin and C-peptide concentrations did not differ during the two treatments. On the other hand, the integrated (area under the curve) postprandial glucagon concentrations were lower (20.9 +/- 1.6 vs. 23.7 +/- 1.3 mg/ml per 5 h, P < 0.05), and glucagon-like peptide 1 (GLP-1) concentrations were higher (1,878 +/- 270 vs. 1,277 +/- 312 pmol/l per 5 h, P = 0.001) during vildagliptin administration compared with placebo. Gastric emptying and meal appearance did not differ between treatments. CONCLUSIONS: Vildagliptin does not alter gastric emptying or the rate of entry of ingested glucose into the systemic circulation in humans. DPP-4 inhibitors do not lower postprandial glucose concentrations by altering the rate of nutrient absorption or delivery to systemic circulation. Alterations in islet function, secondary to increased circulating concentrations of active GLP-1, are associated with the decreased postprandial glycemic excursion observed in the presence of vildagliptin.