Abstract: Single and Double Reinnervation of the Gastrocnemius Muscle in Rats - Experimental Model (Plastic Surgery The Meeting)

Monday, September 26, 2016: 1:45 PM

Andre Coelho Nepomuceno, MD , Plastic Surgery, PUC-Campinas, CAMPINAS, Brazil

Jose Carlos Marques de Faria, MD, PhD , Plastic Surgery, Universidade de Sao Paulo, Sao Paulo, Brazil

Elisa Politani, Medical Student , Plastic Surgery, Universidade de Sao Paulo, Sao Paulo, Brazil

Eduardo Guandeline, Medical Student , Plastic Surgery, Universidade de Sao Paulo, Sao Paulo, Brazil

Washington Lima, MD , Plastic Surgery, Universidade de Sao Paulo, Sao Paulo, Brazil

Marco Longo, MD, PhD , Universidade de Sao Paulo, Sao Paulo, Brazil

Raquel Salomone, MD, PhD , Universidade de Sao Paulo, Sao Paulo, Brazil

Alessandra Grassi Salles, MD, PhD , Universidade de Sao Paulo, Sao Paulo, Brazil

Rolf Gemperli, MD, PhD , Universidade de Sao Paulo, Sao Paulo, Brazil

Presentation PDF file

BACKGROUND: Muscle contraction generated by electrical impulses originated simultaneously from two different neural sources may be an interesting alternative for facial palsy and brachial plexus injury treatment.

OBJECTIVE: To evaluate double and single muscle innervation of the gastrocnemius muscle in an experimental model.

METHODS: Fifty adult Wistar rats after having their right peroneal nerve sectioned were divided into 5 groups: (C) control; (TS) in which the right tibial nerve was also sectioned and not repaired; (EE) where after section, the right tibial nerve was immediately repaired by primary neurorrhaphy; (ES) where after section, the right tibial nerve was immediately repaired by end-to-end neurorrhaphy and by end-to-side neurorrhaphy of the peroneal nerve to the tibial nerve distal to the primary neurorrhaphy site; and (CEE) where after section, the right tibial nerve was immediately repaired by convergent end-to-end neurorrhaphy between the proximal stumps of the tibial and peroneal nerves to the distal stump of the tibial nerve. The outcomes were assessed 12 weeks after the experiment by walking track, electromyography, gastrocnemius muscle weight ratio and histomorphometric analysis of distal tibial nerve.

RESULTS: Compared to simple innervation group (EE), the double innervation groups had higher functional results in walking track (p <0.05). When compared to the EE group, the CEE group showed greater amplitude (p = 0.006) and higher latency (p = 0.041) to electromyography. Regarding muscle weight index, there was no difference between groups of single and double innervation (p> 0.705). Histologic analysis revealed higher axonal density in the CEE group compared to the EE group (p = 0.001) and the ES group (p = 0.002).

CONCLUSION: Both double innervation techniques (ES and CEE) showed earlier and greater functional recovery of the gastrocnemius muscle when compared with simple innervation technique (EE). Animals of the CEE group showed higher number of regenerated axons in the distal stump of the repaired nerve than animals of the others experimental groups.

KEYWORDS: Double innervation, gastrocnemius muscle, rats, facial paralysis, end-to-end neurorrhaphy, end-to-side neurorrhaphy

29867 Single and Double Reinnervation of the Gastrocnemius Muscle in Rats - Experimental Model