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A Meta-Analysis of Complication Rates Among Different SMAS Facelift Techniques.

BACKGROUND
Sub-SMAS rhytidectomy techniques are considered to have a higher complication profile, especially for facial nerve injury, when compared to less invasive SMAS techniques. This results in surgeons avoiding sub-SMAS dissection.


OBJECTIVE
Aggregate and summarize data on complications among different SMAS facelift techniques.


METHODS
A broad systematic search was performed. All included studies: (1) described a SMAS facelifting technique categorized as SMAS plication, SMASectomy/imbrication, SMAS flap, high lateral SMAS flap, deep plane, and composite; and (2) reported the number of postoperative complications in participants. Meta-analysis was performed in accordance with PRISMA guidelines.


RESULTS
183 studies were included. High lateral SMAS (1.85%) and composite rhytidectomy (1.52%) had the highest rate of temporary nerve injury and were the only techniques to show a statistically significant difference when compared to SMAS plication (OR = 2.71 and 2.22, respectively, p < 0.05). There was no difference in the risk of permanent injury amongst techniques. An increase in major hematoma was found for the deep plane (1.22%, OR 1.67, p < 0.05) and SMAS imbrication (1.92%, OR 2.65, p < 0.01). Skin necrosis was higher with the SMAS flap (1.57%, OR 2.29, p < 0.01).


CONCLUSIONS
There are statistically significant differences in complication rates between SMAS facelifting techniques for temporary facial nerve injury, hematoma, seroma, necrosis, and infection. Only high lateral SMAS and composite rhytidectomy techniques showed a statistically significant increase in the odds ratio of temporary neuropraxia. Because these complications occur at such a low rate, they are of limited clinical significance. Technique should be selected based on quality of results and not the complication profile.