first rib

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first rib

the highest rib of the thoracic cage. It moves about the axis of its neck, raising and lowering the sternum. First rib movement during quiet breathing is negligible, but under conditions of stress it can increase the anteroposterior diameter of the chest.
References in periodicals archive ?
3%) of the bilateral cases, the right cervical rib was prominently enlarged and had pseudoarticulation with the 1st rib.
35%) cases, both female, where the cervical ribs had pseudoarticulation with the right 1st rib.
15%) of these patients was a 21-year-old male with isolated defective (interruption) ribs in the cartilaginous component of the right 1st rib and left 2nd rib.
Forty-nine patients (73%) had 1st rib resections and 14 (21%) had cervical rib resections.
The most common abnormality was a postfixed brachial plexus, implying a large conjoined middle and inferior trunk, susceptible to pathological stretching over the 1st rib or an anomalous cervical rib.
Abnormalities seen on CXR CXR abnormalities Total patients (N=63), n (%) * Cervical ribs 11 (17) Complete 4 (6) Incomplete 1 (2) Bilateral 6 (9) High insertion of 1st rib 1 (2) Residual stump of 1st rib 1 (2) Mild spondylosis 1 (2) CXR = chest X-ray.
Rib hypertrophoid 5 (4%) 1 (5%) 6 (4%) scalenus muscle and wide 1st rib Cx rib, fibrous band, and 12 (10%) 1 (5%) 13 (9%) wide 1st rib Cx.
These vessels are also liable to injury in performance of thoracoplasty and other surgical procedures requiring resection of 1st rib, so in these instances less critical knowledge of anatomy of the subclavian artery and its branches would lead to hazard insurgery of neck and upper thorax (5).
After refrigeration for 24 h, carcass collection procedures followed NPPC guidelines (NPPC, 2000); back fat (BF) depth at 1st rib, 10th rib and last lumbar were collected as well as longissimus muscle area (LMA).
Abbreviated variables include last lumber backfat (LLBF), 10th rib backfat (BF10), 1st rib backfat (BF1) and loin muscle area (LMA); [L.
This is a congenital abnormality located above the 1st rib that typically produces no symptoms and requires no therapy.
It is widely continuous with the arm premuscle sheath, and lies almost entirely anterior to the 1st rib.