目的：探讨上臂内侧肌间隔穿支血管的分布规律、主要来源、以及不同穿支体区之间的吻合情况。探讨以肌间隔穿支为血供基础的上臂内侧皮瓣的临床应用，创新术式。探讨吲哚菁绿SPY成像技术在上臂内侧皮瓣术中的应用价值。

方法：①临床观测20例患者、21侧上臂内侧肌间隔的穿支血管情况。建立坐标系，设肱骨内上髁为原点，肱骨内上髁与腋窝顶点连线为y轴，即上臂全长，设相对值为1。将上臂三等分，设近段、中间段和远段肌间隔穿支分别为A、B、C，最近端第一穿支和最远端第一穿支分别为P_p和P_d，统计分析各穿支的数量、出现率、位置和口径等。②解剖4侧乳胶灌注上肢标本，统计上臂内侧肌间隔穿支血管的主要来源。CT扫描12具明胶-氧化铅灌注的整尸标本，应用Mimics工作站三维重建上臂内侧肌间隔穿支血管体区，观测不同穿支体区之间的吻合情况。③以肌间隔穿支为血供基础，介绍上臂内侧皮瓣作为直接远位皮瓣和穿支蒂螺旋桨皮瓣的应用经验，介绍以上臂内侧皮瓣修复单侧全颊部缺损、以背部轴型皮瓣接力修复上臂供区的创新术式。对皮瓣术后转归、双上臂对称性等进行统计分析。④术中应用吲哚菁绿SPY成像技术，辅助评估皮瓣血运、预测坏死，回顾分析，计算统计学指标敏感性、特异性、准确性等。

结果：①21侧上臂共观测到肌间隔穿支95个，每侧3~8个，平均4.5个。穿支A共32个，出现率为95.2%，在y轴的相对值为0.87±0.09，中等以上口径的穿支占78%；穿支B共33个，出现率为100%，相对位置为0.49±0.09，中等以上穿支占55%；穿支C共30个，出现率为85.7%，相对位置为0.20±0.06，中等以上穿支占47%。最近端第一穿支P_p共20个，出现率为95.2%，相对位置为0.92±0.06，中等以上穿支占90%；最远端第一穿支P_d共18个，出现率为85.7%，相对位置为0.17±0.05，中等以上穿支占56%。②4侧上肢标本共观测到肌间隔穿支17个，直接发自肱动脉者13个，占76.5%。Mimics工作站重建的三维视图可清晰显示肱动脉、尺侧上副动脉、尺侧下副动脉及其穿支等，不同穿支体区之间存在不减少口径的真性吻合，呈曲线形沿上臂长轴分布。③36例患者共转移上臂内侧皮瓣42块，直接远位皮瓣29块，穿支蒂螺旋桨皮瓣13块。修复的缺损部位包括头颈部26个、腋窝7个、肘关节4个、手部3个、胸部2个。其中，3例患者共转移3块上臂内侧皮瓣修复单侧全颊部缺损，修复上臂供区的接力皮瓣为带蒂肩胛旁皮瓣（1块）和胸背动脉穿支皮瓣（2块）。皮瓣面积最大为22×15cm，最小为10×4cm，7块皮瓣出现远端部分的表浅或全层坏死，予以换药或手术处理后愈合，余皮瓣全部成活。术后测量双上臂周径，对比无统计学差异（P>0.05）。术后随访效果均满意。④12例患者13块上臂内侧皮瓣术中应用吲哚菁绿SPY成像技术，计算敏感性为66.7%，特异性为80.0%，准确性为76.9%。

结论：上臂内侧皮瓣的主要血供为直接发自肱动脉的肌间隔穿支血管，在近、中、远三等分段内，均存在较恒定的穿支血管。在不同穿支体区之间，存在不减少口径的曲线形真性吻合。以肌间隔穿支为主要血供基础，上臂内侧皮瓣的应用自由、灵活、可靠，可作为近端蒂或远端蒂直接远位皮瓣、穿支蒂螺旋桨皮瓣进行转移，修复头颈部、腋窝、肘关节、手部、胸部甚至乳房等多处皮肤软组织缺损。术中借助吲哚菁绿SPY成像技术，可客观有效地评估皮瓣血运、以减轻或防止皮瓣坏死。

Objective: This study aimed to investigate the septocutaneous perforator patterns of the medial arm flap, the predominant source vessels and the vascular anastomosis among different perforasomes. Based on these perforators, the clinical applications of the medial arm flap were introduced and several novel designs were developed. The value of intraoperative indocyanine green SPY imaging was evaluated.

Methods: ①21 arms of 20 consecutive patients who underwent medial arm flap surgery were included in the study. A reference coordinate system was set up, in which the y-axis joined the medial epicondyle to the axillary apex. The total length of the arm was measured and designated as 1. The arm was divided into three parts and the perforators of the proximal, the middle and the distal part were designated as A, B and C, respectively. The first perforator of the proximal part and the last perforator of the distal part were designated as P_p and P_d. The number, presence rate, location and size of perforators were recorded and analyzed. ②Four red-latex injected upper limbs were dissected. The septocutaneous perforators of the medial arm and the source vessels were identified. Twelve fresh cadavers were injected using the lead oxide-gelatin injection technique, then imaged using a spiral computed tomography scanner. Three-dimensional reconstructions of the septocutaneous perforator angiosomes in the medial arm were performed using Materialise’s Interactive Medical Image Control System software. The anastomosis between adjacent peforasomes was analyzed. ③Based on the septocutaneous perforators, the medial arm flap was used as proximally or distally based pedicle flap and perforator-based propeller flap. A novel approach of total cheek reconstruction was introduced with the pre-expanded medial arm flap, while the donor site was closed using a pedicle axial back flap. The flap survival and complications were reviewed and the postoperative symmetry of bilateral arms was analyzed. ④Indocyanine green SPY imaging was used intraoperatively to evaluate the flap perfusion and predict necrosis. The sensitivity, specificity and accuracy were calculated respectively.

Results: ①A total of 95 perforators were identified in 21 arms, with an average of 4.5 perforators (range, 3 to 8). Perforator A with a total number of 32 was present in 95.2 percent of cases and located 0.87±0.09 from the medial epicondyle. The proportion of the medium- and large-sized (M and L) perforator was 78 percent. Perforator B with a total number of 33 was present in 100 percent and located 0.49±0.09, with a proportion of 55 percent of M and L perforator. Perforator C with a total number of 30 was present in 85.7 percent and located 0.20±0.06, with a proportion of 47 percent of M and L perforator. Perforator P_p with a total number of 20 was present in 95.2 percent and located 0.92±0.06, with a proportion of 90 percent of M and L perforator. Perforator P_d with a total number of 18 was present in 85.7 percent and located 0.17±0.05, with a proportion of 56 percent of M and L perforator.②17 perforators were identified in 4 specimens and 13 (76.5 percent) originated from the brachial artery directly. The perforators of the brachial artery, superior ulnar collateral artery and inferior ulnar collateral artery were demonstrated clearly in three-dimensional view by using Mimics. True anastomosis was found linking adjacent perforasomes along the longitudinal axis of the arm in a curved shape. ③42 medial arm flap surgery were performed in 36 patients, including 29 proximally or distally based pedicle flaps and 13 perforator-based propeller flaps. The locations of the defects included head and neck (n = 26), axilla (n = 7), elbow (n = 4), hand (n = 3), and chest (n = 2). 3 patients had a total unilateral cheek defect. 3 pre-expanded medial arm flaps were separately used for cheek defect reconstruction, with the donor sites in the medial arm closed using a pedicle parascapular flap and 2 pedicle thoracodorsal artery perforator flaps. The maximum dimension of the medial arm flap was 22×15cm and the minimum 10×4cm. 7 flaps suffered superficial or full-thickness necrosis in the distal part of the flap and healed secondarily with conservative or surgical management. The remaining survived completely. The circumferences of bilateral arms were measured postoperatively and a good symmetry was preserved. The patients were followed up routinely and all were satisfactory with the final results. ④Indocyanine green SPY imaging was used in 13 flaps of 12 patients with a sensitivity, specificity and accuracy of 66.7%, 80.0% and 76.9%, respectively.

Conclusions: The blood supply of the medial arm flap was predominantly based on the septocutaneous perforators of the brachial artery. The constant perforators could be found in the proximal, middle and distal part. True anastomosis linked theses perforasomes in a curved shape. Based on the septocutaneous perforators, the medial arm flap could be used as a proximally or distally based pedicle flap and a perforator-based propeller flap, with great versatility and reliability, to reconstruct the defects of head and neck, axilla, elbow, hand, chest and even the breast. Intraoperative indocyanine green SPY imaging was a valuable adjunct to evaluate the flap perfusion and prevent necrosis.