Bounding Pulse at Anterior Cervical Artificial Disc Replacement Site
A visible bounding pulse at the surgical site after anterior cervical artificial disc replacement at C5-C7 is NOT a normal finding and warrants immediate clinical evaluation, as it may indicate proximity of the carotid artery to the surgical site, vascular injury, pseudoaneurysm formation, or baroreflex dysfunction.
Immediate Clinical Concerns
Vascular Proximity and Injury Risk
- The anterior cervical approach places the carotid artery and other major vascular structures in close proximity to the surgical field, and a visible pulsation suggests either abnormal vascular positioning or a complication 1.
- While the provided evidence does not specifically address pulsations after artificial disc replacement, the anatomical considerations are identical to those for anterior cervical discectomy and fusion (ACDF), where vascular complications are recognized 1.
Baroreflex Failure Syndrome
- Baroreflex failure syndrome has been documented following anterior cervical surgery (ACDF from C4-C7), presenting with paroxysmal blood pressure surges, diaphoresis, and anxiety that can be difficult to control 1.
- This condition results from injury to the baroreceptors in the carotid sinus during anterior cervical dissection and can manifest postoperatively 1.
- Prompt recognition is critical as it requires specialist referral and may reduce patient morbidity 1.
Differential Diagnosis to Consider
Pseudoaneurysm or Vascular Injury
- Although rare, vascular complications including carotid artery injury can occur during anterior cervical procedures 2.
- A pulsatile mass at the surgical site could represent a pseudoaneurysm requiring urgent vascular imaging.
Normal Postoperative Swelling vs. Pathologic Finding
- While some degree of soft tissue swelling is expected postoperatively, a bounding pulse that is visibly prominent is not a normal finding and suggests either vascular proximity due to tissue changes or a pathologic process 1.
Recommended Immediate Actions
Clinical Assessment
- Measure blood pressure bilaterally to assess for volatile hypertension or asymmetry that might suggest baroreflex dysfunction or vascular compromise 1.
- Assess for associated symptoms including diaphoresis, anxiety, headache, or neurological changes 1.
- Palpate the pulse carefully to determine if it is truly bounding or if there is a pulsatile mass.
Imaging Evaluation
- Obtain urgent vascular imaging (CT angiography or duplex ultrasound) to evaluate the carotid artery and vertebral artery for injury, pseudoaneurysm, or abnormal positioning 1.
- Standard postoperative radiographs may show prosthesis positioning but will not adequately assess vascular structures 3.
Specialist Consultation
- Consider immediate vascular surgery consultation if imaging reveals vascular pathology 1.
- Cardiology or autonomic specialist referral may be warranted if baroreflex failure syndrome is suspected based on blood pressure volatility 1.
Important Caveats
Device-Specific Considerations
- Artificial disc replacement has different biomechanical properties compared to fusion, but the vascular anatomy and surgical approach are identical 4, 3.
- Prosthesis migration or malposition could theoretically alter local anatomy, though this is rare with proper surgical technique 3.
Time Course Matters
- Baroreflex failure syndrome typically manifests in the immediate postoperative period with volatile hypertension 1.
- Pseudoaneurysm may present days to weeks after surgery with a pulsatile mass.
This finding should never be dismissed as "normal postoperative changes" without thorough vascular and hemodynamic assessment 1.