Clinical Analysis Of Surgical Treatment For 22 Cases Of Postaxial Polydactyly

Objective:The aim of this study was to report the results of surgical treatment of congenital postaxial polydactyly,and to explore the choice of surgical methods for different classifications.Methods:We retrospectively reviewed the details of patients with congenital postaxial polydactyly treated in the Department of Hand Surgery of China-Japan Union Hospital of Jilin University from January 2019 to March 2021.Excluding the patients with other diseases,there were 22 patients with 25 feet,5 boys and 17 girls,aged from 8 months to 14 years,with an average age of 5.2 years.Postaxial polydactyly was found on the bilateral side in 3 cases,unilateral side in 19 cases,3 cases were complicated with finger syndactyly.According to the morphological classification of Konno and Hirase,the 25 cases were classified into type A,type B-1 and type B-2.In type A,the fourth,fifth and sixth toes are independent and separated.Type B-1 is the fifth and sixth toe adherent（including complete syndactyly and incomplete syndactyly）,but there is no syndactyly between them and fourth toe.Type B-2 is the adherent between the fourth,fifth and sixth toe.Further,we evaluated the radiological configurations（development and axis）and morphological characteristics（appearance and size）,the inferior toe and the superior toe which has good shape,bone structure and axis were distinguished.We excised the inferior toe and retained the superior toe.However,when we failed to select the superior toe,if it is the type A and type B-1,we excised the sixth toe in order to better restore the top foot contour.If it is the type B-2,we excised the fifth toe,and separated the syndactyly.The web space was simultaneously reconstructed using a rectangular flap or a dorsal gull wing flap.Free skin grafting was performed if there was skin defect on the lateral side of toe.After the fifth toe was removed,the transverse metatarsal ligament was repaired to narrow the forefoot and maintain stability.At the same time,the medial joint capsule of the reserved toe was tightly sutured to prevent valgus deformity of the reserved toe after operation.When the sixth toe was removed,we reconstructed the insertion point of abductor digiti minimi to prevent varus deformity of the reserved toe after operation.If there was protuberant deformity of the fifth metatarsal head,it would be shaved intraoperatively to avoid postoperative pain at the point.If there was toe deviation deformity in the reserved toe,we would correct by wedge osteotomy or arthroplasty.The patients were followed up by outpatient reexamination combined with Wechat pictures.Postoperative evaluation was based on the clinical evaluation suggested by Phelps and Grogan.The patients were followed up to record whether they had pain,difficulty in wearing shoes,callous,significant deformity of retained toe and the subjective satisfaction of patients or guardians with scar.Doctors used Vancouver Scar Rating Scale（VSS）to evaluate the scar situation,and analyzed the correlation between postoperative VSS score and age.The web creeping degree of the reconstructed web space was observed and measured,degree 0 is no web creeping,and the web space is soft or thickened due to scar hypertrophy.The web creeping of degree 1 is that not exceeds the proximal interphalangeal joint level of the retained little toe.The web creeping of degree 2 is that exceeds the proximal interphalangeal joint level of the retained little toe.Results:In this group,there were 3 feet of type A,the fifth and sixth toes were determined as the dominant toe by radiology in 1 foot respectively,and the inferior toe was excised and the dominant toe was retained;we cannot distinguish the superior and inferior toes by radiology and morphology in one foot,and the sixth toe was removed.There were 9 feet in type B-1,the fifth toe was determined as the dominant toe by radiology in one foot,and the sixth toe was determined as the dominant toe by radiology and morphology in 6 feet.The inferior toe was excised and the dominant toe was retained.One foot could not distinguish the superior and inferior toes by radiology and morphology,and the sixth toe was removed.There were 13 feet in type B-2,the sixth toe was determined as the dominant toe in 9 feet.The superior and inferior toes of 4 feet could not be distinguished by radiology and morphology.All of the fifth toes were excised in type B-2.In type B-2,rectangular flap was used to reconstruct 2 web spaces,dorsal gull wing flap was used to reconstruct 11 web spaces and skin graft was applied in two cases.All patients had no infection,flap and skin graft necrosis.Nineteen patients（21 feet）were followed up for 6 to 29 months,with an average of 17.2 months.The patients had no pain,deformity,callous and difficulty in wearing shoes.The clinical result was excellent in 10 feet,good in 10 feet and poor in 1 foot.The guardian was satisfied with the cosmetic result in 10 feet,general in 10 feet and dissatisfied in 1 foot.The web creeping result was degree 0 in 10 feet,degree 1 in 1foot and degree 2 in 0 foot.The VSS score was 0-5,with an average of 2.5.VSS score was significantly positively correlated with age.Conclusions:1.Morphology and radiology should be considered comprehensively in the classification of postaxial polydactyly,so as to guide the surgical treatment.The inferior toe should be excised and the superior toe should be retained.When we failed to distinguish the superior and inferior toes,the sixth toe of type A and the fifth toe of type B-1 should be excised.The fifth toe of type B-2 should be excised and the web spaces is reconstructed simultaneously.2.The severity of postoperative scar is positively correlated with age.Scar is an important factor affecting postoperative appearance.We should pay attention to the timing of operation,reasonably design the flap.Attention should be paid to relaxation suture during operation,and measures should be taken to prevent scar hypertrophy after operation.