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thirty - one patients with oral cancer attending the affiliated stomatology hospital of kunming medical university , who underwent repair of soft tissue defects after oral cancer resection using a pedicled forearm flap , from july 2012 to july 2016 , were included . of these patients , 19 were male and 12 were female ; patients were aged between 39 and 69 years , with a mean age of 54 years .
there were 13 patients of tongue carcinoma , 7 patients of buccal carcinoma , 7 patients of mouth floor carcinoma , and 4 patients of gingival carcinoma . in terms of tnm stage , 24 patients were t1n0m0 and 7 patients were t2n0m0 ( table 1 ) .
the preoperative diagnoses were confirmed by pathological examination in all patients . under general anesthesia via nasoendotracheal intubation , all the patients underwent 2-team surgery simultaneously .
recipient site ( performing functional neck lymph node dissection and removal of the primary tumor ) : using a modified lateral lip 
submandibular approach , the initial incision began from the lower lip vermilion , approximately 0.5  cm from the ipsilateral cheilion , and then descended downward and backward along the nasolabial sulcus to about 1.5  cm beneath the inferior edge of the mandible ( fig .
soft tissue was isolated from the depth of the platysma to the lower edge of the mandible ; the external jugular vein was ligated at the superficial layer . in the deeper layer , the facial artery ,
the posterior facial vein , and the internal jugular vein were located and protected for blood vessel anastomosis .
the lymph and cellular tissue was cleared away between the internal jugular vein and the carotid bifurcation , and the lymph node and lymphoid tissue was also cleared away around the internal jugular vein , the anterior cervical and deep cervical arteries .
then , toward the jaw and chin , the submandibular gland , lymph node , and lymphoid tissue of the submandibular and submental region were removed ( fig .
after cleaning away the fat and lymphoid tissue outside the carotid sheath in the carotid triangle , the tunica was carefully opened , dissected , and separated along both sides of the internal jugular vein ; it was then fully freed after the internal jugular vein was pulled forward , and the adipose and lymphoid tissues of intrathecal and perivascular region were cleared away .
light iodophor was used to rinse the oral cavity , and the primary tumor lesion resected with an enlarged margin of about 1.0  cm . from the edge of the tumor lesion ,
donor site ( performing forearm free flap transplantation ) : the location of the radial artery and cephalic vein was marked on the surface of forearm for a length of about 6 and 5  cm , respectively , using methylene blue .
then , the marked blood vessels were used as the axis to design a spindle - shaped free flap with a size similar to the recipient site ( length : ca .
5  cm , width : ca . 4  cm ) , using methylene blue .
finally , a 10-cm line was marked at the proximal part of the spindle - shaped free flap ( fig .
1c ) . during surgery , the radial artery , radial vein , cephalic vein , and cutaneous nerve
were first located , and the vascular pedicle , about 15  cm long , separated ( fig .
the radial artery and the cephalic vein were each ligated , and the cutaneous nerve was carefully protected during the operation .
then , the prepared pedicled forearm free flap was moved to the area of the oral recipient site , and it was verified that the facial artery and the posterior facial vein were in good condition .
microsurgical anastomosis of the radial artery and cephalic vein to the facial artery and posterior facial vein , respectively , was then performed . during surgery
, the blood vessels were frequently washed with diluted heparin sodium salt solution to avoid formation of thrombi in these blood vessels . eventually , the flap was closed and sutured to the area of the oral recipient site ( fig .
it was ascertained that there were no obvious bleeding points , and 2 negative - pressure drainage balls were placed under the sutured wound region .
next , a full - thickness skin flap , spindle - shaped and with a size of about 4  cm    5  cm , the same size as the forearm flap , was made in the lower abdomen .
this was transferred to the forearm wound area to repair forearm skin flap , and the wound closed by suturing ( fig .
1f ) , and with bandage pressure . finally , routine postoperative tracheotomy was performed .
thirty - one patients with oral cancer attending the affiliated stomatology hospital of kunming medical university , who underwent repair of soft tissue defects after oral cancer resection using a pedicled forearm flap , from july 2012 to july 2016 , were included . of these patients , 19 were male and 12 were female ; patients were aged between 39 and 69 years , with a mean age of 54 years .
there were 13 patients of tongue carcinoma , 7 patients of buccal carcinoma , 7 patients of mouth floor carcinoma , and 4 patients of gingival carcinoma . in terms of tnm stage , 24 patients were t1n0m0 and 7 patients were t2n0m0 ( table 1 ) .
under general anesthesia via nasoendotracheal intubation , all the patients underwent 2-team surgery simultaneously . recipient site ( performing functional neck lymph node dissection and removal of the primary tumor ) : using a modified lateral lip 
submandibular approach , the initial incision began from the lower lip vermilion , approximately 0.5  cm from the ipsilateral cheilion , and then descended downward and backward along the nasolabial sulcus to about 1.5  cm beneath the inferior edge of the mandible ( fig .
soft tissue was isolated from the depth of the platysma to the lower edge of the mandible ; the external jugular vein was ligated at the superficial layer . in the deeper layer , the facial artery ,
the posterior facial vein , and the internal jugular vein were located and protected for blood vessel anastomosis .
the lymph and cellular tissue was cleared away between the internal jugular vein and the carotid bifurcation , and the lymph node and lymphoid tissue was also cleared away around the internal jugular vein , the anterior cervical and deep cervical arteries .
then , toward the jaw and chin , the submandibular gland , lymph node , and lymphoid tissue of the submandibular and submental region were removed ( fig .
after cleaning away the fat and lymphoid tissue outside the carotid sheath in the carotid triangle , the tunica was carefully opened , dissected , and separated along both sides of the internal jugular vein ; it was then fully freed after the internal jugular vein was pulled forward , and the adipose and lymphoid tissues of intrathecal and perivascular region were cleared away . finally , the neck operation region was flushed with copious amounts of physiological saline .
light iodophor was used to rinse the oral cavity , and the primary tumor lesion resected with an enlarged margin of about 1.0  cm . from the edge of the tumor lesion ,
donor site ( performing forearm free flap transplantation ) : the location of the radial artery and cephalic vein was marked on the surface of forearm for a length of about 6 and 5  cm , respectively , using methylene blue .
then , the marked blood vessels were used as the axis to design a spindle - shaped free flap with a size similar to the recipient site ( length : ca .
5  cm , width : ca . 4  cm ) , using methylene blue .
finally , a 10-cm line was marked at the proximal part of the spindle - shaped free flap ( fig .
1c ) . during surgery , the radial artery , radial vein , cephalic vein , and cutaneous nerve
were first located , and the vascular pedicle , about 15  cm long , separated ( fig .
the radial artery and the cephalic vein were each ligated , and the cutaneous nerve was carefully protected during the operation .
then , the prepared pedicled forearm free flap was moved to the area of the oral recipient site , and it was verified that the facial artery and the posterior facial vein were in good condition .
microsurgical anastomosis of the radial artery and cephalic vein to the facial artery and posterior facial vein , respectively , was then performed . during surgery
, the blood vessels were frequently washed with diluted heparin sodium salt solution to avoid formation of thrombi in these blood vessels . eventually , the flap was closed and sutured to the area of the oral recipient site ( fig .
it was ascertained that there were no obvious bleeding points , and 2 negative - pressure drainage balls were placed under the sutured wound region .
next , a full - thickness skin flap , spindle - shaped and with a size of about 4  cm    5  cm , the same size as the forearm flap , was made in the lower abdomen .
this was transferred to the forearm wound area to repair forearm skin flap , and the wound closed by suturing ( fig .
1f ) , and with bandage pressure . finally , routine postoperative tracheotomy was performed .
in this study , 31 patients were followed up for 3 months to 3 years .
the pedicled forearm flap survived in 30 patients ( 96.77% ) , vascular crisis occurred in 3 patients ( 9.67% , 2 patients with successful rescue ) .
postoperatively , the oral cavity , neck , and forearm wounds underwent 1-stage healing ( fig .
2 ) , without salivary fistula , chyle leakage , or infection complications . postoperative wound healing .
( a ) the lateral view 1 month after the operation , showing postoperative wound healing of the oral , maxillofacial , and neck region .
( b ) the frontal view 2 months after the operation , showing that the forearm flap had 1-stage healing .
( c ) the frontal view 20 days after the operation , showing that the forearm donor site had healed well .
( d ) the frontal view 3 months after the operation , showing that the forearm donor site had healed well . among the 3 patients with vascular crisis ,
postoperative exploration found that , in 2 patients , the vascular crisis was due to folding and compression of the vascular anastomosis , and in the remaining patient , it was caused by flap hematoma . during the follow - up period ,
1 patient died of cancer metastasis to the lung 2 years after surgery , and the remaining 30 patients were satisfied with the local appearance and function ; the articulation and swallowing function of the patients were improved greatly .
a forearm free flap can be used to repair defects of oral and maxillofacial soft tissue , and is commonly used to repair large tissue defects after oral cancer surgery .
a forearm flap has the advantage of suitable color and texture , moderate thickness , a long vascular pedicle , a good blood supply , and strong resistance to infection , and can be used to form a composite tissue flap for the reconstruction of a large oral and maxillofacial defect as well as perforating defects .
the blood supply of the radial skin flap is mainly supplied by the radial artery , which has 2 constant companion veins .
the cephalic vein is the main reflux superficial vein of the forearm flap , and the cephalic vein or radial vein can be used for venous return in the forearm flap .
the diameter of the cephalic vein is sufficiently wide , and the wall of the vein is moderately thick , to be a good match for the head and neck veins .
the cephalic vein is often selected in clinical use for vascular anastomosis , but when making the skin flap , the cephalic vein and the fascia tissue between the radial artery and radial vein should be retained as much as possible . if necessary , we even use both the cephalic vein and the radial vein .
it has been reported in the literature that free tissue flap transplantation with these 2 venous anastomoses is the most reliable method for preventing secondary thrombosis , and can effectively prevent or reduce the probability of free flap vein crisis .
even if one vein were to become blocked , sufficient reflux could be achieved through the other vein , improving the success rate of this free tissue flap transplantation .
it is necessary to cut the vascular terminus flat and remove the adventitia of the vascular terminus for 2 to 3  mm before the vascular anastomosis .
if a vascular spasm occurs during the operation , it is necessary to use lidocaine heparin saline to flush and clear the small blood clot inside the vessels .
furthermore , it is important to ensure that no tension , no torsion , and no thrombosis occur in the blood vessels at the anastomotic site .
after anastomosis of the blood vessels , the patency should be assessed immediately , and when the surface of the recipient site is closed , the patency of the blood vessels should be evaluated again .
if vascular patency is not optimal , testing should be repeated , and if necessary , vascular anastomosis should be performed again .
careful postoperative nursing is also an important factor in the success of forearm free flap transplantation .
vascular crisis occurs mostly in the first 24 to 72  hours postoperatively , and particularly in the first 24  hours after the operation .
it has been reported that if surgical exploration is performed within 4 to 6 hours when vascular crisis occurs , the success rate of rescue success is about 30% . except for the vascular crisis that occurred in 3 patients ( 2 patients with successful rescue ) ,
the remainder of the surgeries in this group were successful , and the total graft survival rate was about 96.77% .
this emphasizes that the free forearm flaps have a high survival rate in the reconstruction of soft tissue defects after oral cancer resection . in this group of patients ,
the shape of the skin flap was good , the color was normal , and the flap did not show any marked distension .
compared with previous patients , the oral function of the patients in this group was markedly improved . in conclusion ,
the pedicled forearm flap is a useful skin flap for repairing soft tissue defects after resection of oral cancer , and its clinical application should be promoted .
objective : to investigate the clinical application of a pedicled forearm flap in the reconstruction of soft tissue defects after oral cancer resection.methods:a retrospective analysis was performed on 31 patients with oral cancer in the affiliated stomatology hospital of kunming medical university . 
 the patients underwent repair of soft tissue defects , resulting from oral cancer resection , using a pedicled forearm flap . 
 patients were followed up for 3 months to 3 years to observe the survival rate of the pedicled forearm flap and the recovery of the patient 's appearance and oral function.results:the pedicled forearm flap survived in 30 patients ( 96.77% ) , and 3 patients showed flap vascular crisis ( 9.67% ; 2 patients were successfully rescued ) . 
 the articulation , chewing , and swallowing function of the patients were improved after surgery.conclusion:the pedicled forearm flap has advantages in terms of color and texture , its moderate thickness , long vascular pedicle , good blood supply , and strong infection resistance . 
 it has a high survival rate and is an excellent skin - muscle flap suited to the repair of soft tissue defects after oral cancer resection .