[Imaging-anatomic study of diaphragmatic sternocostal triangle with double-phase 16-row MDCT].

This study was aimed to determine the effects of respiratory phase, age, sex and body mass indexes (BMI) on the visibility and morphological characteristics of the diaphragmatic sternocostal triangle in normal adults shown by multi-detector computed tomography (MDCT). A total of 100 normal adults were consecutively recruited and scanned with 16-row MDCT at the end of deep expiration and inspiration. The visibility and morphological characteristics of diaphragmatic sternocostal triangle were observed. All cases were grouped according to the respiratory phase, age, sex and BMI, respectively. The visibility rates by MDCT among different types of sternocostal triangles at the inspiratory or the expiratory phases were calculated and compared, and the visibility rate was correlated with age, sex, and BMI, respectively. In addition, the CT features of diaphragmatic hernia (n=2) were recorded and analyzed. The visibility rate of trigonum sternocostal was 43% at the end of inspiration and 32% at the end of expiration. No difference was found in regard to age, gender and BMI (P > 0.05). Rupture of diaphragm and the features of adjacent abdominal organs into thoracic cavity were revealed clearly on multiplanar reformation (MPR) images of MDCT in 2 patients with diaphragmatic hernia. The visibility rates of diaphragmatic sternocostal triangle were associated with the respiratory movement. MPR on MDCT could be useful for revealing the anatomic structure of diaphragm and the radiological features of diaphragmatic hernia. Furthermore, double-phase scanning of MDCT provides feasible method for studying the physiologic information of diaphragm movement in normal status and abnormal status.

Anomalous pectoral musculature.

Anomalous disposition of pectoral muscles was encountered in an adult female cadaver on the left side. A prominent cleft separating the sternocostal and clavicular portions of the pectoralis major was noticed. The fibers of pectoralis major were partially fused with the deltoid, resulting in obliteration of the deltopectoral groove. Interestingly, cephalic vein was seen traversing superficial to the clavicular portion of the pectoralis major and pierced it to drain into the axillary vein. The pectoralis minor was inserted mainly on the coracoid process and few fibers were found blending with the coracobrachialis and short head of biceps brachii. Further, pectoralis minimus, a rare anatomic variant, was also observed lying superior to pectoralis minor. It was innervated by a twig from the lateral pectoral nerve at its superficial surface. Awareness of possibility of such anomalous muscles is important for surgeons operating on the chest wall.

Sternocostal joints. Anatomic, radiographic and pathologic features in adult cadavers.

Using radiographic-pathologic correlation, we studied the sternocostal joints derived from 27 consecutive cadavers and one additional cadaver with rheumatoid arthritis. Radiographic findings that were tabulated included joint space narrowing, sternal or costal osteophytes, articular calcification, vacuum phenomena, and the degree of ossification of the costal cartilages. The first sternocostal joint could be classified as either a synchondrosis or synostosis in every instance; however, a joint cavity lateral to the first sternocostal joint represented a normal variation and was seen radiographically in 10 specimens. The second sternocostal joint was synovial in type and intimately related to the manubriosternal joint; cavitation within this joint was present bilaterally in 36% of our specimens. Degenerative changes in the sternocostal articulations were characterized much more frequently by sternal osteophytes than by costal osteophytes or joint space narrowing. Calcification compatible with chondrocalcinosis was observed in two cadavers. Radiographic and pathologic evidence of synovial inflammation was evident in the sternocostal joints of the rheumatoid specimen.

Histologic comparison of the costochondral, sternoclavicular, and temporomandibular joints during growth in Macaca mulatta.

The costochondral joint (CCJ) is commonly used to replace defective mandibular condyles in children for the restoration of normal temporomandibular (TMJ) growth and function. However, continued and harmonious growth following rib grafting is the exception rather than the rule. This may be due to the differences in the growth characteristics of the costal cartilage and the condyle. A joint that is similar both developmentally and structurally to the TMJ is the sternoclavicular joint (SCJ). The purpose f this study was to describe histologically the SCJ and CCJ during growth in Macaca mulatta and to compare the histomorphologic features with those of the TMJ. Costochondral and sternoclavicular joints were obtained from infant, juvenile, adolescent, and adult Macaca mulatta. The histologic sections were compared with mandibular condyles of the same ages available in our laboratory. The results indicate that the TMJ and SCJ are very similar morphologically throughout the growth period. The clavicular head contained layers of cartilage typical of the mandibular condyle, i.e., articular, prechondroblastic, chondroblastic, hypertrophic, and endochondral ossification layers, at each age during growth. Like those in the condyle, the hypertrophic cartilage cells were arranged in an apparently random, noncolumnar fashion. The CCJ, however, did not resemble the condyle but appeared to be more similar to the growth plate in a long bone epiphysis during growth. The results of this investigation indicate that the SCJ may be more suitable for mandibular condylar replacement than the CCJ.

[Anterior joints of the thoracic cage]. / Contribution à l'étude des articulations antérieures de la cage thoracique.

The chondro-sternal, interchondral, costo-chondral joints and the upper and lower sternal joints were studied in the thorax of 60 children and human adults. Chondro-sternal joints occur as frequent symphyses in the 5th, 6th and 7th joints or ellipsoid joints which are mainly found in the 2nd, 3rd and 4th joints. Diarthrosis frequency increases with age in every joint. An articular space appears particularly in the lower part of the 2nd, 3rd and 4th joints; in fewer cases a space is found in the upper part of the 5th, 6th and 7th joints. These partial spaces disappear with age and are replaced by spaces occupying the whole articulation. The first joint is a synchondrosis which does not vary with age. Interchondral joints are diarthrodial or trochoid joints from earliest childhood and their frequency increases with age. No direct articular contact was observed between the 9th and 10th costal cartilages. Costo-chondral joints are synarthrosis. The upper sternal joint, which is a synchondrosis in the child, may develop into a non-synovial cavity with age, or even turn into synostosis. The lower sternal joint is a synchondrosis which develops partially towards synostosis.

Articulations of the ribs: a pictorial review.

The joints of the ribs are true articulations and may be involved by local or general affections of the skeleton. Scoliosis, kyphosis, infections, arthritis (local or general types) may result in fibrosis, abnormal configuration, or ankylosis of the joints in question. In certain types of fractures of the dorsal vertebrae, disruption of the contiguous rib articulations may result in fibrosis or bony depositions and secondarily aid in local stabilization of the fracture. Narrowing of the intercostal spaces, as noted in kyphosis, scoliosis, and arthritis of the dorsal region, does not seem to be routinely associated with clinical findings of intercostal neuralgia.

[The 7th sterno-costal articulation (author's transl)]. / La 7e articulation sterno-costale.

A study of 200 human thoracic anterior walls (150 of adults and 50 of children) allows to distinguish 3 types of articulations at the internal extremity of the 7th costal cartilage: a lateral sterno-costal articulation, a prexiphoïdian sterno-costal articulation and an articulation between the two 7th costal cartilages. Each type may or may not have an articulating space. The only diarthrodial articulating spaces are found at the level of the articulation between the two 7th costal cartilages. All the other articulations may be considered as symphyses which, with age, may present a non-synovial space. The different types of articulations vary with age, the 7th cartilages being closer together in the child than in the adult. In the child there is a characteristic vascular network between the sternum and the 7th costal cartilages.