Classification,Characteristics And Treatment Of Osseous Syndactyly

Objective: To explore the imaging classification and anatomical characteristics of osseous syndactyly and its guiding significance on operation pointer and operation scheme.Methods: Review and analyse the clinical data of 43 cases of osseous syndactyly,involving a total of 76 finger webs.According to the radiographic characteristics of bones and joints,they were divided into bone fusion type and bone bridge type.Summarize the position,segments and anatomical characteristics of these two types of osseous syndactyly as well as whether they were accompanied by dysfunction,and the finger webs,body and nail morphology,joint stability,flexion and extension functions of fingers after operation according to the corresponding scheme for different types were followed up.Results: There were 57 finger webs of bone fusion type,which could show normal bone mass or lack of bone mass.There were 19 finger webs of bone bridge type,connected with extra bone or stunted residual phalanx.There were 57 finger webs connected by only one segment(distal section 47,middle section 2,and proximal section 8),and 19 finger webs connected by two segments(metacarpal and proximal section3,proximal and middle section 9,middle section and distal section 7),but none of them were connected by three segments.63 bony union finger webs were surgically separated,and all of the cases were separated by one operation except one case which was divided into two times.After operation,5 fingers were found with vascular and nerve abnormalities,and 7 fingers were found with tendon abnormalities.Postoperative wound healing was delayed in 3 cases with 5 fingers,all of which were bone fusion type,and there was no reoperation due to wound nonunion.There were 51 fingers in 34 cases who were followed up for more than 6months.There were 5 fingers with narrow finger webs,47 fingers with lateral deviation,46 fingers with joint instability and 73 fingers with flexion and extension disorder.7 cases underwent reoperation due to defects in appearance and function.Conclusion: This classification of the osseous syndactyly can reflect the severity and anatomical characteristics of the osseous union,it can guide the selection of the surgical pointer and the surgical scheme.The main causes of secondary deformities after surgery are difficult coverage of bone wounds and lack of joint capsules and ligaments.The flap after separation of bone bridge type can often cover the bone wound,and the shape of the finger after axial correction by osteotomy is relatively good with less secondary dysfunction.Bone fusion type osseous syndactyly refers to that the skin grafting may not survive well after the fascial flap of bone wound is covered,and it is often accompanied with lateral deviation of fingers which is caused by scar contracture,instability of joints which is caused by lack of ligaments,stiffness of joints which is caused by the correction of joint deformities.The osseous syndactyly which is only involved the distal section,and no matter what type it is,the postoperative appearance and function are less affected.For the bone fusion type with lack of bone mass,and the osseous syndactyly which involving more than two segments of the finger,the appearance and function after separation are poor,so the surgical pointer should be strictly controlled and it may not carry out the surgical intervention or the surgery only keeps one finger.