Does Steal Phenomenon Exist in Multiple Neurotization?-An Experimental Rat Study.

BACKGROUND: Nerve transfers from one common donor nerve to recipient nerves with multiple target branches can yield slower and unpredictable recovery in the target nerves. Our hypothesis is that steal phenomenon exists when multiple nerve neurotization comes from one donor nerve. METHODS: In 30 Sprague-Dawley rats, the left ulnar nerve (UN) was selected as the donor nerve, and the musculocutaneous nerve (MCN) and median nerve (MN) as the recipient target nerves. The rats were separated into three groups (10 rats in each): group A, UN-to-MCN (one-target); group B, UN-to-MN (one-target); and group C, UN-to-MCN and MN (two-target). The right upper limbs were nonoperative as the control group. Outcome obtained at 20 weeks after surgery included grooming test, muscle weight, compound muscle action potential, tetanic muscle contraction force, axon counts, and retrograde labeling of the involved donor and target nerves. RESULTS: At 20 weeks after surgery, muscles innervated by neurotization resulted in significant worse outcomes than the control side. This was especially true in two-target neurotization in the parameter of muscle weight and forearm flexor muscle contraction force outcome when compared to one-target neurotization. Steal phenomenon does exist because flexor muscle contraction force was significantly worse during two-target neurotization. CONCLUSION: This study proves the existence of steal phenomenon in multiple target neurotization but does not significantly affect the functional results. Postoperative rehabilitative measures (including electrical stimulation, induction exercise) and patient compliance (ambition and persistence) are other crucial factors that hold equivalent importance to long-term successful recovery.

Simultaneous Reconstruction of the Lower Lip with Gracilis Functioning Free Muscle Transplantation for Facial Reanimation: Comparison of Different Techniques.

BACKGROUND: Functioning free muscle transplantation is currently the gold standard for the reconstruction of facial paralysis, focusing more on the upper lip reconstruction rather than on the lower lip. This study aimed to compare different lower lip reconstructive methods when performing functioning free muscle transplantation for facial reanimation. METHODS: A retrospective review of functioning free muscle transplantation for facial reanimation from 2007 to 2015 was performed. Patients were divided into three groups: in group 1 (n = 15), a free plantaris tendon graft anchored to the gracilis muscle was passed into the lower lip to create a loop within; in group 2 (n = 12), an aponeurosis tail of the gracilis muscle was attached to the lower lip; and in group 3 (n = 18), no suspension of the lower lip was performed. All patients had at least 2 years of follow-up. Outcomes were assessed by photographs and videos, including subjective evaluation of midline deviation and horizontal tilt and objective analysis of smile dimensions and area. RESULTS: A total of 45 patients were included. Results from the subjective evaluation demonstrate group 1 patients having the best improvement (overall score: p = 0.004 and p = 0.005, Fisher's exact test). The objective evaluation showed group 1 and 2 patients with better results compared with group 3 (horizontal component, p = 0.009; vertical component, p = 0.004; area distribution, p < 0.001, Kruskal-Wallis test). CONCLUSIONS: Both plantaris tendon graft and gracilis aponeurosis achieved better improvement in subjective and objective evaluations than those who had no reconstruction of the lower lip. In particular, the plantaris tendon graft can achieve the most lower lip excursion with overall improved symmetry. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Lymphangiomatous Tumors of the Neck: Tips to Avoid Iatrogenic Nerve Injuries in the Brachial Plexus Region.

Lymphangiomas are rare malformations of the lymphatic system and can often be found in the neck region, where its proximity to the brachial plexus may cause compressive neuropathy and possible iatrogenic injuries during dissection. We report 4 cases of lymphangiomas with compression of the brachial plexus that were successfully removed without permanent nerve injuries and present a literature review of the preoperative approach and surgical techniques. A preoperative multidisciplinary approach can help surgeons predict what they may encounter during the surgery. A careful and stepwise dissection of the vital structures surrounding the tumor, especially the brachial plexus anatomy, is critical to avoiding severe complications. Incomplete resection or leakage of the lymph could result in higher rate of recurrence.