As the descending genicular artery supplies multiple perforating branches around the knee joint,it can be used in corticocancellous,osteomusculocutaneous and other composite tissue flaps to repair composite tissue defects at one stage.Consequently it plays a very important role in the field of reconstruction surgery.At present,however,there has been no systematic review of its clinical applications.Having reviewed all the recent reports available on the free tissue perforator flaps with descending genicular artery,we classified them into five major forms.In this paper,we comment on their anatomical mechanisms,variations and clinical applications.Additionally,we predict that digital technology will be used in the future clinical application of the perforator tissue flaps with descending genicular artery.

Objective To clarify the function of LIM and SH3 domain protein-1 (LASP1) and ferritin in rhBMP2-induced osteogenic differentiation of beagle bone marrow mesenchymal stem cells (BMSCs).Methods After BMSCs from 3-18-month-old C57BL/6J mice were cultured adherently for 24 hours,they were subjected to osteogenic differentiation for 7,14 and 21 days in 3 groups.BMP2 (100 μg/L) and osteogenic differentiation medium was added in the experimental group,only osteogenic differentiation medium was added in the control group,and nothing was added in the blank group.Osteoblast differentiation was determined by examining marker genes (Runx2,OSX,OCN and OPN) using qRT-PCR.The protein expression of both LASP1 and ferritin was investigated using western blotting.After LASP1 and ferritin were silenced in the cells in the experimental group after transfection of shRNA to target LASP1(m),rhBMP2-induced osteogenesis was repeated to verify the roles of LASP1 and ferritin in osteoblast differentiation.Results The qRT-PCR showed successful osteoblast differentiation in the experimental group.Western blotting verified significant down-regulation of LASP1 and up-regulation of ferritin in the experimental group.After the LASP1 gene was silenced,the expression levels of osteoblast differentiation marker genes in the experimental group were higher than those in the control group.Conclusions rhBMP2 can induce mouse BMSCs to differentiate into osteoblasts in a significant manner.Combined with our preliminary research,the present study may confirm that LASP1 and ferritin,which play an important role in regulating cytoskeleton activity and iron metabolism,are critical in the osteogenic differentiation of mouse BMSCs induced by rhBMP2.

With deepening understanding of surgical treatment of calcaneal fractures,clinical applications of external fixators have drawn more attention.At present,however,there has been no systematic review of such applications for intra-articular calcaneal fracture.This review collected all the recent reports available on such applications to analyze the use and clinical indications of different external fixators.Moreover,on the basis of our own clinical experience,we further proposed a novel treatment protocol for intraarticular calcaneal fractures which integrates internal and external fixation and minimally invasive techniques.

Objective To explore the clinical technical points of the treatment of soft tissue defect of the foot and ankle with the supercharged peroneal artery perforator propeller flap,and to provide theoretical support by anatomical observation.Methods From January,2010 to February,2018,a total of 10 patients with soft tissue defect of foot and ankle were treated with supercharged peroneal artery perforator propeller flap.Cause of injury:trauma in 7 cases,wound ulcer in 1 case,and poor healing of the calcaneus incision in 2 cases.Defect site:5 cases of heel,2 cases of medial and lateral malleolus,and 3 cases of dorsum and sole.The size of flap ranged from 6.0 cm×3.0 cm to 16.0 cm×5.0 cm.All patients were followed-up at 1,3,6 months after operation,and the function recovery was judged by AOFAS Ankle Hindfood Scale at 3 months post-opertively.From November,2016 to May,2017,the anatomical basis and operative points of the supercharged peroneal artery perforator flap were summarized.Results All the 10 cases of supercharged peroneal artery perforator propeller flap survived.Two of them had local epidermal necrosis at the proximal end of the flap.After 1 to 2 weeks of dressing,they finally healed.The other 8 cases healed well.Anatomical studies showed that different planes of the supercharged peroneal artery perforator propeller flap can only reduce the compression of the double pedicles and reduce the distal necrosis rate of the flap by rotating in different rotation directions.Conclusion The supercharged peroneal artery perforator propeller flap can enhance the blood supply and venous return in the "big paddle" artery of the flap,preventing distal necrosis.