Table 1.

Basic study characteristics of all included studies and their intervention groups. Multiple intervention groups within the same study are labelled with letters A–D. For commercially produced wrappers, the production company is depicted in brackets behind the material. Abbr.: PBS = phosphate-buffered saline, AA = ascorbic acid, HA = hyaluronic acid, PLA = polylactide, PCL = poly(ε-caprolactone), CMC = carboxymethylcellulose (CMC), PE = phosphatidylethanolamine, n = number of animals in group, FU = follow-up time in weeks.

Author	Year	Group	Scarring Induction	Wrapping Material	n	FU
Baltu et al. [27]	2017	A	Epineurectomy	Buccal mucosa graft	24	8
Dumanian et al. [13]	1999	A	Epineurectomy	Free fat grafts	14	8
Finsterbush et al. [26]	1982	A	Crush injury, muscle cauterization	Semirigid 15 mm silicone tube, cut longitudinally	30	8
Görgülü et al. [14]	1998	A	External neurolysis	Collagen fibers soaked with aprotinin	22	6
		B	Abrasive injury	Collagen fibers soaked with aprotinin	22	6
		C	External neurolysis	Collagen fibers soaked with PBS	22	6
		D	Abrasive injury	Collagen fibers soaked with PBS	22	6
Hernandez-Cortes et al. [25]	2010	A	Perineurectomy + muscle cauterization	Oxidized regenerated cellulose wrap	40	6
Kikuchi et al. [24]	2020	A	Muscle cauterization	E8002 wrapping (Kawasumi Laboratories Inc., Tokyo, Japan)	7	6
		B	Muscle cauterization	E8002 AA- wrapping (Kawasumi Laboratories Inc., Tokyo, Japan)	7	6
Li et al. [23]	2018	A	Crush injury	Chitosan conduit	15	12
		B	Crush injury	HA gel	15	12
		C	Crush injury	Chitosan conduit + HA gel	15	12
Murakami et al. [22]	2014	A	Chronic constriction injury by nerve ligation	Allogenic vein wrap	30	20
Ohsumi et al. [21]	2005	A	External/internal neurolysis + muscle cauterization	Viscous alginate sol	8	6
Okui et al. et al. [16]	2010	A	Internal neurolysis + muscle cauterization	Honeycomb poly-lactide film	42	6
		B	Internal neurolysis + muscle cauterization	Cast poly-lactide film	12	6
Özgenel et al. [20]	2004	A	Epineurectomy	Human amniotic membrane	12	12
		B	Epineurectomy	Human amniotic membrane + HA injection	12	12
Petersen et al. [15]	1996	A	Internal neurolysis	ADCON-T/N gel (Gliatech, Inc., Cleveland, OH, USA)	9	4
		B	Internal neurolysis	Control gel	9	4
Shintani et al. [19]	2018	A	Muscle cauterization	PLA/PCL tube	12	6
		B	Muscle cauterization	1% HA	8	6
Smit et al. [18]	2004	A	External neurolysis	1% HA	5	6
		B	Crush injury	1% HA	7	6
Yamamoto et al. [17]	2010	A	Internal neurolysis	1% HA	18	6
		B	Internal neurolysis	CMC-PE hydrogel, low viscosity	18	6
		C	Internal neurolysis	CMC-PE hydrogel, high viscosity	18	6