|Year : 2015 | Volume
| Issue : 2 | Page : 113-115
Lateral intermuscular approach to cervical rib - Is it safe?
Amit Chauhan1, Madan Mohan Ray2, Animesh Kumar1, Kanchan Kumar Sabui1
1 Department of Orthopedic Surgery, Park Hospital, Gurgaon, Haryana, India
2 Department of Orthopaedics, Agartala Medical College, Agartala, Tripura, India
|Date of Web Publication||20-Aug-2015|
Department of Orthopedic Surgery, Park Hospital, Gurgaon, Haryana
Source of Support: None, Conflict of Interest: None
Thoracic outlet syndrome is a well known identity, caused due to constriction of the space through which the brachial plexus and the subclavian artery pass from the neck into the axilla, with resultant abnormal pressure upon the plexus and the artery. This can be caused by a cervical rib or pressure due to scalenus anterior muscle. Out of two approaches described-anterior and lateral, when authors encountered two such cases of thoracic outlet syndrome due to cervical rib, lateral intermuscular approach was employed and was found to be safe, adequate and effective.
Keywords: Cervical rib, lateral intermuscular approach, thoracic outlet syndrome
|How to cite this article:|
Chauhan A, Ray MM, Kumar A, Sabui KK. Lateral intermuscular approach to cervical rib - Is it safe?. J Med Soc 2015;29:113-5
| Anatomy|| |
The complete cervical rib extends out laterally from the seventh lateral vertebral process for varying distances, then turns forward and downward between the scalenus anticus and medius muscles to meet the costal cartilage of the first rib.  As the rib turns downward, the brachial plexus passes over it; then on its downward course the subclavian artery arches backward and laterally over it. Usually the scalenus anticus has attached itself to the cervical rib as the rib has pushed forward.  Still lateral to the rib and outside of the scalenus anticus, arches the subclavian vein, lower than the artery. The muscle lies between the vein and the cervical rib. Above the vein and nearly over the rib, two branches of the thyroid axis, the suprascapular and transverse cervical arteries passes transversely across the shoulder. Above these arteries is the inferior belly of the omohyoid running in the same direction. The phrenic nerve passes downwards along the anterior surface of the scalenus anticus; with the costal arch,usually out of danger, lies the carotid sheath with the common carotid artery, internal jugular vein and the vagus nerve. Over all these structures runs the lower end of sternocleidomastoid laterally and anteriorly with the jugular vein passing down its postero-lateral border.
It has been described that if the rib is long enough the intercostal space between the cervical rib and the first dorsal rib is occupied by intercostal muscles and the vein and artery are exactly as in the thoracic intercostal spaces.  Also it is believed that the scalenus and intercostals are from the same muscle plane, forming two sheets, the inner forming the scalenus anticus and minimus, the outer the scalenus medius and posticus.  These sheets of muscle are continued as the internal and external intercostals. The subdivisions of the scalenes are made by the passage of vessels and nerves. The course of the subclavian artery through the scalenes corresponds to that of an intercostal artery through the chest wall.
| Approach|| |
The lateral intermuscular approach to the cervical rib was popularised by Samuel Klienberg.  An oblique incision of two and one-half inches, parallel to the creases of the neck, is made in the posterior triangle of the neck a little below the level of the cricoid cartilage. The middle of the incision should be opposite to the seventh cervical vertebra. After cutting superficial fascia and the platysma, expose the deep fascia, incise it vertically and retract it posteriorly to expose trapezius. Structures seen in the surgical field now will be, from before backwards, the upper trunk of brachial plexus, the scalenus medius and posterior muscles and the levator scapulae. Make a plane in between scalenus posterior and levator scapulae by retracting former muscle anteriorly and latter posteriorly to expose the base of the cervical rib. Always be gentle in retraction manoeuvres to avoid and unwanted injuries. Now elevate the scalenus posterior and medius to expose the entire length of the cervical rib and and fascial band if present. After full exposure, cut the cervical rib near its origin, raise it from its bed to its very tip, liberate it by severing any restraining tissues including the fascial band. With this approach, there is hardly any chances of injuring any vessels and infact surgeon may not see brachial plexus even. With this approach only one can inspect scalenus anterior too by retracting the cut inner edge of the deep cervical fascia which should be a routine of any surgeon after excision of culprit cervical rib. To be in an advantageous position, this approach can be modified in cases of big cervical ribs by making a plane between scalenus medius and posterior and not the original approach.
| Case reports|| |
A twenty-eight year old female housewife presented with chief complaints of severe pain and a prominent swelling in the right neck region and tingling sensation over medial aspect of right forearm for last four years. Pain was continous in nature and was only relieved with medications. The swelling was bony hard in consistency without any overlying skin changes or visible pulsation. The intrinsic muscles mainly the hypothenar muscles of the right hand were atrophied [Figure 1].
A thirteen year old male child presented with pain in the left neck region, tingling sensation along the medial border of left forearm, numbness of ring and little finger of left hand for past one and a half years. Subclavian artery pulsation was visible in the left neck region with a positive bruit heard on auscultation.
Adson and Roos test were positive in both of the cases. Routine blood investigations were within normal limits. Plain Anteroposterior and lateral radiographs of cervicothoracic spine confirmed the diagnosis of cervical rib [Figure 2].
In both these cases, cervical ribs were approached by lateral intermuscular approach [Figure 3] and were excised [Figure 4] which were confirmed by postoperative X-Rays [Figure 5].
| Discussion|| |
Anterior approach was popularised by Adson and Coffey  as it gives a thorough exposure of the scalenus anterior muscle which too is one of the constricting agents for the thoracic outlet syndrome. Without any intentions of undermining this approach, we would like to draw attention to cervical rib which, being the other cause of thoracic outlet syndrome, cannot be approached fully through this anterior approach. Donald and Morton  reported a patient in whom thoracic duct was lacerated while employing anterior approach. They also commented on the occurrence of temporary paralysis of the phrenic nerve which is in intimate relation with the scalenus anterior muscle. In lateral approach, no such structures are encountered. Adson  objects to lateral approach as it might injure brachial plexus by forward retraction of the scalenus posterior and medius. But by gentle retraction of the muscles this complication can be avoided very easily according to our experience. Well, neither of the approach can be considered the best for resection of cervical rib and scalenus anterior, we suggest with our experience of two such cases where cervical rib is culprit, lateral intermuscular approach is an avascular, safe and adequate approach with full accessibility to the cervical rib without any danger to vessels and brachial plexus in gentle hands.
Financial support and sponsorship
No sources of support in the form of grants, equipment and drugs received for the study.
Conflicts of interest
There are no conflicts of interest.
| References|| |
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]