The capsular vein as a novel surgical landmark for safe access to the temporomandibular joint: a retrospective cohort study.

Background: Temporomandibular joint (TMJ) surgery carries a risk of facial nerve injury and intraoperative bleeding, especially in patients with anatomical distortion due to ankylosis or inflammation. This study introduces a novel anatomic landmark-the capsular vein-and evaluates a preauricular approach utilizing this vein to improve surgical safety.

Methods: A retrospective cohort study was performed on 104 patients (109 TMJs) who underwent TMJ surgery between 2014 and 2022. During the approach, a vein consistently found at the superior aspect of the glenoid fossa (designated the capsular vein) was identified and ligated without requiring formal facial nerve dissection. The primary outcomes were the incidence and duration of postoperative facial nerve weakness. Secondary outcomes included the presence of any facial paresthesia and other postoperative symptoms.

Results: The capsular vein was identified and ligated in all cases. No intraoperative bleeding requiring hemostasis (e.g., electrocautery) was observed. Temporary facial nerve weakness occurred in 3.8% of patients (n = 4). Additional complications included transient facial paresthesia (1.9%, n = 2) and headache (4.8%, n = 5), with no permanent deficits reported.

Conclusion: The capsular vein serves as a reliable anatomic landmark for TMJ surgery, enabling a safe and efficient approach without the need for facial nerve dissection. Its use minimizes intraoperative bleeding and nerve injury, particularly in patients with ankylosis or severe inflammation, and may improve surgical outcomes across a variety of TMJ procedures.