A cervical rib is an extra rib that forms above the normal first rib, typically growing from the seventh cervical vertebra. This anatomical variation is congenital. While prevalence varies, it is generally uncommon, occurring in approximately 0.5% to 1% of the population. This additional rib is more frequently observed in women. Most people with a cervical rib remain unaware of its presence, as it often causes no symptoms.
Associated Symptoms and Complications
Symptoms arise when the cervical rib, or fibrous bands connected to it, press against nearby nerves or blood vessels in the thoracic outlet. This compression can lead to Thoracic Outlet Syndrome (TOS). Most TOS cases related to a cervical rib involve nerve compression, leading to neurogenic symptoms.
Individuals may experience pain in the neck, shoulder, or arm, which can radiate into the hand. Numbness or a tingling sensation can occur in the fingers, particularly the ring and little fingers. Weakness in the grip or arm fatigue are common neurological manifestations. These nerve-related symptoms can be exacerbated by specific arm movements, such as raising the arms overhead or repetitive activities.
When blood vessels are compressed, vascular symptoms may appear. The hand and fingers can become discolored (pale or bluish) and feel cold due to reduced blood flow. Swelling in the arm or hand might occur, and some individuals may notice a throbbing lump near the collarbone, indicating arterial involvement. Though less common than neurogenic TOS, vascular compression requires prompt attention due to potential complications like blood clots.
Diagnosis and Identification
Diagnosis typically begins with a thorough physical examination. A doctor may feel the neck for an abnormal bony structure. Specific maneuvers, such as Adson’s test, might be performed to reproduce symptoms or assess for changes in the arm’s pulse, indicating subclavian artery compression.
Imaging studies confirm the diagnosis and assess the anomaly’s extent. A simple chest or neck X-ray is usually the initial step, showing the bony outline. For a detailed view of how the rib interacts with surrounding soft tissues, nerves, and blood vessels, advanced imaging like a CT scan, MRI, or ultrasound may be used. Nerve conduction studies measure electrical signal speed along nerves, helping detect damage or compression.
Management and Treatment Options
Treatment is pursued only if symptoms are present. The initial approach involves conservative, non-surgical methods to alleviate discomfort and improve function. Physical therapy plays a significant role, focusing on exercises that strengthen shoulder and neck muscles and improve posture to reduce thoracic outlet pressure.
Patients may be advised to modify activities that trigger or worsen symptoms, such as avoiding prolonged overhead movements or repetitive tasks. Non-steroidal anti-inflammatory drugs (NSAIDs) can manage pain and inflammation. Muscle relaxants may also reduce muscle spasms.
If conservative measures do not provide sufficient relief, or if severe vascular issues or persistent neurological symptoms are present, surgical intervention may be considered. Cervical rib resection involves the surgical removal of the extra rib. This surgery aims to relieve compression on nerves and blood vessels, alleviating symptoms and preventing complications. In some cases, the first rib may also be partially removed to further decompress the area.