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Background: High-resolution magnetic resonance imaging (MRI) of subungual glomus tumors has been recently reported., Objective: Our purpose was to compare high-resolution MRI and standard MRI for the diagnosis of 44 glomus tumors of the toes and fingertips., Methods: Glomus tumors (11 cases) were first examined by MRI with a commercial surface coil (set 1). Thirty-three other glomus tumors and one tumor from set 1 were then examined with a high-resolution module designed for skin imaging (set 2)., Results: All 44 glomus tumors were identified with MRI. The limits of the tumors were detected in 54% of set 1 and 100% of set 2. A capsule was present in most cases, but was incomplete or absent in eight cases. Subtypes of glomus tumors were more easily differentiated in set 2., Conclusion: Standard MRI was adequate to detect glomus tumors, but high-resolution MRI assessed tumor characteristics more accurately.

High-resolution sagittal magnetic resonance images depict an oval area in the dermis beneath the nail matrix that gives a particular signal. This study defines the magnetic resonance imaging characteristics of this area and examines its correlation with the lunula. A high-resolution surface gradient coil specially designed for skin imagining was used on a 1.5 T magnetic resonance unit. The subnail matrix (SNM) areas of 12 subjects had a significantly longer T2 relaxation time and a higher enhancement ratio after injection of gadolinium than did the nail bed dermis. The length of the SNM area distal to the free edge of the proximal nail fold was highly correlated with the length of the lunula (R = 0.98) in 30 fingers and 10 toes. The total length of the SNM area was somewhat correlated with the nail thickness (R = 0.86) in 30 fingers. The histology and microvascularization of the subungual tissue in 21 fingers showed that this SNM area had specific features: The area was composed of loose connective tissue without bundles, and the reticular and subdermal vascular networks had large regular meshes in this oval area. The lunula is shown to be linked to a well-defined area in the underlying dermis with a specific histology and microvascularization.

Examination of the knee joint by magnetic resonance imaging (MRI) is a noninvasive technique of proven reliability as regards lesions of the menisci and ligaments. It provides good definition of the different anatomic structures. The meniscofemoral ligaments have been observed with varying frequency and may be responsible for false images. However, it is important to detect them in cases of hypermobile discoid menisci of the 'Wrisberg ligament type' in order to guide the surgeon in their excision during total meniscectomy. We have attempted to assess the ability of MRI to visualise the meniscofemoral ligaments in correlation with an anatomic study and to identify certain anatomic pitfalls. This study will allow better investigation of the hypermobile menisci associated with the meniscofemoral ligaments. A clinical case is reported to illustrate its practical importance.

This anatomic study is based on 50 adult cadaver upper extremities. The general disposition of the forearm arteries and muscles and the main anatomic variations encountered are specified. Constant existence of an "anterior oblique artery" satellite of the pronator teres was established. The median nerve artery was principally dedicated to the flexor digitorum superficialis and participated appreciably in the constitution of palmar arches in only one case. A supernumerary intermedial radial muscle was found only in two cases. The abductor pollicis longus and extensor pollicis brevis appeared as a single muscular and vascular unit in 84 percent of cases. All the arteries destined for muscles were reckoned whatever their caliber might be. Despite its limitations, this study confirms the very great number of the forearm muscular pedicles. Each forearm contained an average of 264 muscular vascular pedicles. The systematization of the origins and destinations of the 13,158 muscular pedicles is described in a numbered manner for each of the 20 normal forearm muscles and for each of the 12 studied arterial segments. The pronator teres was likely to be supplied by all the anterior arteries of the upper limb. The flexor carpi radialis had one or two dominant pedicles originated from the recurrens ulnaris anterior, recurrens ulnaris, or ulnaris-interossea communis arteries, and many transversal branches originated from the radial artery. The flexor carpi ulnaris was supplied in its proximal third by the recurrens ulnaris posterior artery and in its distal two-thirds by many branches of ulnar artery.(ABSTRACT TRUNCATED AT 250 WORDS)

The results of an anatomic study based on 50 fresh adult cadaver upper extremities are analysed. All the arterial pedicles of each forearm muscle were counted, and each muscle was weighed. Each forearm contained an average number of 264 muscular pedicles. The relative mass fraction of each muscle was calculated, as was its "muscular vascular index" or MVI (number of pedicles divided by the weight of the muscle in grams). Half of the forearm muscles had a significant statistical relationship between their weight and their number of vascular pedicles. The other half had no statistical relationship. These two statistical muscular groups (with and without a statistical relationship) did not clearly correspond to anatomic or functional groups. No muscular group based on the average of MVI was found. Each of the 20 forearm muscle had finally its own characteristics of weight, number of pedicles, and MVI. The average MVI was 0.9 (from 0.4 to 1.8). The global muscular vascular index (GMVI) is the division of the total number of muscular pedicles of a forearm by the total muscular weight of this forearm. The average GMVI was 0.8 (from 0.4 to 1.6). In spite of its theoretical and practical limits, the MVI concept approximately reflects the high vascular density of the forearm muscles.

The authors describe a modified radiological lateral view according to the points of tangency of the radial articular surface. The view allows the separate study of the radio-scaphoïd and the radiolunate joint spaces, which are otherwise superimposed on a classical side view. This view has a clinical interest especially when treating malunion deformities.

A study of 18 elbows in the cadaver allowed the medial fascia of the radial collateral ligament of the articular capsule to be clearly separated. Section of this ligament associated with that of the anterior fascia, without section of the ulnar collateral ligament always produces luxation of the elbow if it is in flexion. The integrity of the insertion surface of the epicondyles does not stop this luxation. This therefore confirms the arthrographic and operative observations recently published.

The metacarporetinacular fascicle, the fourth fascicle of the medial collateral metacarpotrapezial ligament, was examined in 25 anatomic specimens. It contributes to stability of the ligament and plays an important role in the pronosupination of the thumb. This role becomes determinate when the geometry of the articular surfaces is disturbed.

Colles' fractures with important displacement are accompanied by a subdislocation of the carpus backwards. The authors describe a radio-lunate sagittal index that measures the posterior displacement. This index should be instored during the reduction of the fracture.

Thirty-seven dissections have shown that the skin of the low back is innervated by the lateral branches of the dorsal rami of T12 and LI in 22 cases (60%) or T12 L1 and L2, in 10 cases (27%) or T12 L1 and L2 receiving an anastomosis from L3 in 5 cases (13%). The most medial nerve crossed the iliac crest through a rigid osseo-aponeurotic orifice located 7-8 cm from the midline which was seen compressing the nerve in 2 instances. This pattern of distribution may sometimes explain unilateral low back pain.