Is Second Metatarsal Protrusion Related to Metatarsophalangeal Plantar Plate Rupture?

OBJECTIVE. The purpose of this study was to determine whether the relative length of protrusion of the second metatarsal, measured on MRI and weight-bearing foot radiography, predicts the diagnosis of second metatarsophalangeal (MTP) joint plantar plate (PP) tear on MRI. MATERIALS AND METHODS. We retrospectively evaluated 166 consecutive patients (211 feet). Patients had undergone weight-bearing foot radiography and forefoot MRI. Using the Coughlin method, two independent observers measured second meta-tarsal protrusion length on radiography and MRI. MRI findings were classified as normal PP, complete PP tear, or degenerative or partial PP tear. RESULTS. Patients had a mean age of 47 ± 14.6 (SD) years, and 131 (78.9%) were women. MRI measurements were highly correlated with radiographic measurements (r = 0.882; 95% CI, 0.866-0.898; p < 0.001). A significant correlation was found between length of protrusion and cases classified as either normal PP or PP tear. Patients with a normal PP had a mean protrusion length of 4.11 ± 1.35 mm on radiographs and 2.61 ± 1.31 mm on MR images, whereas those with a PP tear had a mean protrusion length of 4.75 ± 1.53 and 3.05 ± 1.34 mm, respectively. ROC curve analysis showed that protrusion length cutoff values of 5.47 mm measured on radiographs and 3.17 mm on MR images were correlated with MTP PP tear. CONCLUSION. We identified a linear correlation between second metatarsal protrusion measured on MRI and that measured on radiography, with values about 35% higher for the latter. Our study showed an association between length of protrusion of the second metatarsal and PP rupture and identified a cutoff value for the second meta-tarsal overlength that is associated with these tears.

Assessment of fatty infiltration of the multifidus muscle in patients with adolescent idiopathic scoliosis through evaluation by magnetic resonance imaging compared with histological analysis: a diagnostic accuracy study.

To evaluate fat infiltration in the multifidus muscle close to the scoliotic curve as seen in MRI compared with the histological evaluation in patients with adolescent idiopathic scoliosis (AIS). The evaluation of fatty infiltration in the multifidus muscle of patients with AIS by MRI was compared with biopsy. Fatty infiltration was greater in concave side than in the convex side in both MRI (P=0.005) and biopsy evaluation (P=0.026). There was no correlation between the fatty infiltration findings evaluated through MRI and biopsy. The MRI measurements do not express accurately the tissue changes observed in the biopsy.

Ultrasound characteristics of gouty tophi in the olecranon bursa and evaluation of their reproducibility.

OBJECTIVES: To describe the ultrasound characteristics of gouty tophi in the olecranon bursa and to evaluate their reproducibility. METHODS: A prospective study of the ultrasound features of 35 sites of tophi nodulations in the elbows of 31 men (mean 54.6 years). The findings were evaluated dynamically following pre-established standards. The static images were evaluated by another radiologist and were reviewed by the first examiner. RESULTS: The most frequent characteristics of tophi are: hyperechogenicity (91.7%), poorly defined contours (88.6%), multiple grouped nodules (85.6%) and heterogeneity (68.6%). Intra-observer agreement is almost perfect for echogenicity (K = 1.0), moderate for the involvement of the olecranon bursa (K = 0.47) and fair for other characteristics. Inter-observer agreement is substantial for the echogenicity (K = 0.65), fair for the echotexture (K = 0.27) and the presence of a perilesional hypoechoic halo (K = 0.34) and slight for other characteristics. CONCLUSIONS: The most frequent characteristic of tophi is hyperechogenicity. The intra-observer and inter-observer concordance for echogenicity are almost perfect and substantial, respectively. Knowledge of characteristics of the tophi in the elbow and their intra and inter-observer reproducibility may assist in establishing parameters for monitoring treatment and setting up criteria for differential diagnosis of processes involving the olecraneon bursa.