研究目的

本研究基于三维数字化的计算机断层扫描血管造影(Computed Tomography Angiography,CTA)数据，通过分析Poland综合征患者锁骨下动脉及其分支的形态及胸廓畸形的发生情况及特点，探讨单侧锁骨下动脉及其分支异常与Poland综合征胸廓畸形之间的关系，分析其可能的致病机制;通过对胸壁组织缺损及背阔肌肌瓣解剖结构的三维数字化分析，验证背阔肌肌瓣转移术修复Poland综合征胸大肌缺损的可行性，并通过队列研究验证三维数字化技术辅助的单一腋窝切口内窥镜下背阔肌切取术修复Poland 综合征胸壁畸形的安全性和有效性。

研究方法

l．对2014年1 月至2021 年12 月在整形外科医院49名Poland综合征患者的CTA数据，使用Amira软件进行三维模型重建和三维数字化分析，统计其锁骨下动脉、椎动脉、胸廓内动脉的解剖形态学情况(包括血管的长度、容积和平均内径)，运用t检验分析Poland综合征中锁骨下动脉及其分支形态学差异与患侧胸大肌缺失严重程度间的关系。

2. 对2014年1 月至2021 年12 月在整形外科医院49名Poland综合征患者的CTA数据，使用Amira软件进行三维模型重建和三维数字化分析，对健侧的胸大肌、胸小肌、背阔肌及患侧的残存胸大肌及胸小肌进行图像分割，统计各肌瓣的体积，统计分析患侧胸背血管的显影情况及形态学特征，验证背阔肌肌瓣转移修复Poland综合征患者胸大肌组织缺损的可行性并利用三维数字化技术辅助背阔肌瓣的切取和塑形等手术设计。

3．2015 年1 月至2018 年12 月，在整形外科医院招募Poland 综合征患者，采用经腋窝横切口内窥镜辅助背阔肌转移进行胸壁重建或乳房再造(联合乳房假体置入)。术前进行胸背CTA检查，定位患侧胸背血管，明确患侧背阔肌的发育情况。术后对背阔肌肌瓣成活情况、胸背部形态以及并发症情况进行随访，并统计以下数据:背阔肌肌瓣面积、假体体积、对侧乳房手术情况、手术各步骤时间、引流时间。采用疼痛视觉模拟量表评估术后疼痛程度;采用Breast-Q 量表重建模块评估女性患者心理社会幸福感、乳房满意度及所有患者对手术结果的满意度;采用上肢功能障碍量表(DASH 量表)对患者手术前、后的上肢功能进行评估。采用配对t 检验分析患者手术前、后的Breast-Q 量表和DASH 量表得分差异。

研究结果

1.49例Poland综合征患者患侧锁骨下动脉的长度为73.59±15.5 mm，容量为1259.47±480.27 mm³，平均内径2.25±0.35 mm，相比健侧锁骨下动脉的长度74.32±16.82 mm，容量1254.36±517.04 mm³，平均内径2.22±0.37 mm，无统计学差异。其中胸大肌完全缺失患者患侧的锁骨下动脉长度为67.8±8.41 mm，容量为978.6±317.65 mm³，平均半径为2.06±0.25 mm，胸大肌部分缺失患者患侧的锁骨下动脉长度为74.6±16.29 mm，容量为1307±490.12 mm³，平均半径为2.28±0.36 mm，完全胸大肌缺失患者与部分胸大肌缺失患者患侧锁骨下动脉的长度、容量及平均内径均无统计学差异。

2.49例Poland综合征患者患侧椎动脉的长度为36.05±11.04 mm，容量为134.03±51.37 mm³，平均内径1.07±0.22 mm，相比健侧椎动脉的长度43.71±51.38 mm，容量154.32±64.14 mm³，平均内径1.14±0.19 mm，均无统计学差异。其中胸大肌完全缺失的患侧的椎动脉长度为42.14±19.78 mm，患侧椎动脉容量为116.18±41.64 mm³，患侧椎动脉管径平均半径为0.93±0.21 mm，而胸大肌部分缺失患者患侧的椎动脉长度为35.13±9.23mm，患侧椎动脉容量为136.73±52.69 mm³，患侧椎动脉管径平均半径为1.09±0.21 mm，完全胸大肌缺失的患者与部分胸大肌缺失患者患侧椎动脉的长度、容量及平均内径均无统计学差异。 

3.49例Poland综合征患者患侧胸廓内动脉的长度为184.27±31.47 mm，容量为134.03±51.37 mm³，平均内径0.64±0.16 mm，相比健侧胸廓内动脉的长度194.42±23.99 mm，容量154.32±64.14 mm³，平均内径0.62±0.1 mm，均无统计学差异。其中胸大肌完全缺失患者的患侧的胸廓内动脉长度为200.5±40.58 mm，患侧胸廓内动脉容量为362.86±201.1 mm³， 患侧胸廓内动脉管径平均半径为0.69±0.16 mm，而胸大肌部分缺失患者患侧的胸廓内动脉长度为182.55±30.33 mm，患侧胸廓内动脉容量为313.50±156.07 mm³，患侧胸廓内动脉管径平均半径为0.65±0.11mm，完全胸大肌缺失的患者与部分胸大肌缺失患者患侧胸廓内动脉的长度、容量及平均内径均无统计学差异。

4.在Poland综合征中，胸小肌、前锯肌、背阔肌发育不全或缺失的发生率较高。49例Poland综合征患者中，胸大肌全部缺失的患者28.6%，部分缺失患者71.4%，胸大肌完全缺失患者的胸大肌肌肉缺损量为230.5±91.6 cm³，胸大肌部分缺失患者的胸大肌肌肉缺损量为165.5±78.6 cm³。26.5%的Poland综合征患者存在患侧背阔肌组织的发育不良，73.5%的患者患侧背阔肌发育良好，肌肉组织容量为301.5±108.2 cm³。而患侧背阔肌发育不良的患者患侧背阔肌的肌肉组织容量为172.2±97.8 cm³，仅为背阔肌正常患者组织容量的57.1%。49例患者Poland综合征患者中，患侧背阔肌容量普遍大于健侧胸大肌容量，两者的容量差值为33.8±63.9 cm³。20.4%患侧背阔肌容量平均小于健侧胸大肌容量，两者的容量差值为-48.4±50.2 cm³。79.6%的患侧背阔肌容量平均大于健侧胸大肌容量，两者的容量差值为54.8±48.4 cm³。 

5.49例Poland综合征患者患侧胸背动脉起始端的平均内径为0.59±0.21 mm，健侧胸背动脉起始端的平均内径为0.61±0.17 mm，两者没有统计学差异。65.3%的患者患侧胸背动脉起始端的平均内径大于或等于健侧胸背动脉起始端的平均内径，平均内径的差值约为0.1mm，34.7%患者患侧胸背动脉起始端的平均内径小于健侧胸背动脉起始端的平均内径，平均内径的差值约为0.25 mm。8.1%的患者存在患侧胸背动脉起始端的发育不良，患侧的平均内径为0.9±0.25 mm，健侧的平均内径为0.43±0.06 mm，双侧平均内径的差值为0.47mm。

6.28 例患者接受了腋窝横切口内窥镜辅助的背阔肌转移术来修复胸壁发育畸形，包含男性11 例，女性17 例，转移的背阔肌肌瓣面积为437.2±110.0 cm²，再造乳房的硅凝胶假体大小为240.4±46.0 ml。内窥镜下切取背阔肌耗时69.0±13.9分钟，使用内窥镜分离前侧胸壁腔隙用时32.8±6.0分钟，手术总时长169.4±16.1分钟。术后留置术区引流管的时间为7.6±1.4天。2例接受了对侧的腋窝切口内窥镜辅助假体隆乳术，2例接受对侧自体脂肪颗粒注射隆乳术。术后1 例患者腋窝伤口出现了轻微裂开，1 例患者背部拔出引流后发生了血清肿，1 例患者在术后6 个月左右背阔肌肌瓣轻度下移，其余病患术后恢复良好，无肌瓣坏死、血肿、感染、术中转开放性手术、假体包膜挛缩、移位、破裂发生。疼痛评分术后第1周术后每日逐渐降低。女性患者术后Breast-Q 生活质量量表评分中的乳房满意度、心理社会幸福感显著大于术前。全部患者对手术结果满意程度的评分为(81.3±16.0)分。DASH 量表的评分结果显示手术之后病患的上肢功能不存在明显的功能障碍。

研究结论

l. Poland综合征患者患侧锁骨下动脉及其分支在血管长度、血管容积、血管的管径方面无明显异常，与胸大肌缺失的严重程度之间不存在相关性，因此锁骨下动脉及其分支的病变很可能不是Poland综合征胸部畸形的病因，不支持用SASDS(Subclavian Artery Supply Disruption, SASDS)假说解释Poland综合征胸部畸形发生的病因机制，很可能存在其他的致病原因。

2. CT三维重建技术能够精准评估Poland综合征胸大肌缺失量和背阔肌容量，对于应用背阔肌肌瓣进行胸大肌重建手术适应证的选择具有重要作用。Poland综合征患者中患侧胸背动脉普遍存在，在大多数患者中背阔肌的容量足以重建胸大肌。

3. 经腋窝横切口内镜辅助的背阔肌转移术为Poland 综合征患者的胸壁重建和乳房再造提供了一种安全有效的方法，术后美学效果好，并发症发生率低，患者满意度高。

Purpose 

Based on three-dimensional digital Computed Tomography Angiography (CTA) data, this study aimed to analyze the morphology of the subclavian artery and its branches and the occurrence and characteristics of thoracic malformation in patients with Poland Syndrome and to explore the relationship between unilateral subclavian artery and its branches and the possible pathogenesis of thoracic malformation in Poland Syndrome. Through the three-dimensional digital analysis of anatomical structure of chest wall defect and the latissimus dorsi muscle flap, this study aimed to validate the feasibility of latissimus dorsi muscle flap transfer to repair the absence of pectoralis major in Poland Syndrome. Besides, this study aimed to introduce a technique to reconstruct the chest wall and breast for Poland Syndrome patients with endoscopic latissimus dorsi muscle flap via a single transverse axillary incision and evaluate its safety and effectiveness.

Methods 

1.Based on CTA data collected from 49 patients with Poland Syndrome in Plastic Surgery Hospital from January 2014 to December 2021, three-dimensional model reconstruction and three-dimensional digital analysis were performed using Amira software. The morphology of the subclavian artery, vertebral artery and internal thoracic artery (including the length, volume and mean inner diameter of blood vessels) were analyzed, and the relationship between the anatomical morphology of the subclavian artery and its branches and the severity of pectoralis major defect was analyzed by T test.

2. CTA data of 49 patients with Poland syndrome admitted to the Plastic Surgery Hospital from January 2014 to December 2021 were analyzed using Amira software for three-dimensional model reconstruction and three-dimensional digital analysis. The pectoralis major, pectoralis minor of the healthy side and the latissimus dorsi muscle, the remaining pectoralis major and pectoralis minor muscle of the affected side were segmented. The volume of each muscle flap was calculated and the development and anatomical structure of the thoracodosal artery of the affected side were analyzed statistically to verify the feasibility of latissimus dorsi muscle flap transfer to repair the pectoralis major tissue defect and the surgical design of latissimus dorsi flap assisted by three-dimensional digital technology.

3. From January 2015 to December 2018, patients with Poland syndrome were recruited for chest wall reconstruction or breast reconstruction (combined with breast implant) with endoscopically assisted latissimus dorsi muscle flap transfer via axillary transverse incision in Plastic Surgery Hospital. Thoracic and dorsal CTA examination was performed before surgery to locate thoracodosal vessels and evaluate latissimus dorsi muscle on the affected side. The survival of latissimus dorsi muscle flap, chest and back morphology and complications were followed up after surgery. The following data was collected: latissimus dorsi muscle flap area, prosthesis volume, contralateral breast surgery, length of each procedure and drainage time. Visual Analogue Scale of pain was used to evaluate postoperative pain degree. The reconstruction module of Breast-Q scale was used to evaluate the psychosocial well-being of female patients, breast satisfaction and the satisfaction with surgical results of all patients. The upper limb function was assessed by the disabilities of the arm, shoulder and hand Scale (DASH) before and after surgery. Paired T test was used to analyze the differences of breast-Q scale and DASH scale scores between patients before and after surgery.

Results 

1. The length of subclavian artery in 49 patients with Poland syndrome was 73.59±15.5 mm, the volume was 1259.47±480.27 mm³, and the average diameter was 2.25±0.35 mm in the affected side. In the healthy side, the length of that was 74.32±16.82 mm. The volume of that was 1254.36±517.04 mm³, and the average inner diameter of that was 2.22±0.37 mm.There was no statistical differences in the length, volume and average inner caliber between the healthy side and affected side. The length of the subclavian artery in patients with complete pectoralis major loss was 67.8±8.41 mm, the volume was 978.6± 317.65 mm³, and the average radius was 2.06±0.25 mm. The length of the subclavian artery in patients with partial pectoralis major defect was 74.6±16.29mm, and the volume was 1307±490.12 mm³, the average radius was 2.28±0.36 mm, and there were no statistical differences in the length, volume and average inner caliber of the affected subclavian artery between patients with complete pectoralis major absence and patients with partial pectoralis major defect.

2. In 49 patients with Poland syndrome, the length of the affected vertebral artery was 36.05 ±11.04 mm, the volume was 134.03±51.37 mm³, and the average inner diameter was 1.07±0.22 mm. In the healthy side, the length was 43.71±51.38 mm.The volume was 154.32±64.14 mm³, and the average inner diameter was 1.14±0.19 mm. There was no statistical differences in the length, volume and average inner caliber between the healthy side and affected side. The length of the vertebral artery on the affected side with complete pectoralis major loss was 42.14±19.78 mm, and the volume of the vertebral artery on the affected side was 116.18±41.64 mm³. The average radius of affected vertebral artery diameter was 0.93±0.21 mm, while the length of affected vertebral artery was 35.13±9.23 mm and the volume of affected vertebral artery was 136.73±52.69 mm³, the average diameter radius of the affected vertebral artery was 1.09±0.21 mm in patients with partial pectoralis major defect and there were no statistical differences in the length, volume and average inner diameter of the affected vertebral artery between patients with complete pectoralis major absence and patients with partial pectoralis major defect.

3. 49 patients with Poland syndrome had a length of 184.27±31.47 mm, a volume of 134.03±51.37 mm³, and an average diameter of 0.64±0.16 mm of the internal thoracic artery on the affected side. Compared with the normal side, the length of that was 194.42±23.99 mm. The volume of that was 154.32±64.14 mm³, and the average inner diameter of that was 0.62±0.1 mm. The length of the internal thoracic artery was 200.5±40.58 mm and the volume of the internal thoracic artery was 362.86±201.1 mm³ in the affected side with complete pectoralis major muscle defect. The average diameter radius of the internal thoracic artery on the affected side was 0.69±0.16 mm. While the length of the internal thoracic artery on the affected side of the patients with partial pectoralis major defect was 182.55±30.33 mm, and the volume of the internal thoracic artery on the affected side was 313.50±156.07 mm³. The average diameter radius of the affected side of the internal thoracic artery was 0.65±0.11 mm and there were no statistical differences in the length, volume and average diameter of the affected side of the internal thoracic artery between patients with complete pectoralis major defect and patients with partial pectoralis major defect.

4. In Poland Syndrome, the incidence of dysplasia or absence of pectoralis minor, serratus anterior and latissimus dorsi was high. Among the 49 patients with Poland Syndrome, 28.6% of them had total pectoralis major loss and 71.4% of them had partial pectoralis major loss. The total pectoralis major loss was 230.5±91.6 cm³ and partial pectoralis major loss was 165.5±78.6 cm³. The latissimus dorsi tissue was dysplastic in 26.5% of patients with Poland Syndrome, and well developed in 73.5% of patients with latissimus dorsi with a muscle tissue volume of 301.5±108.2 cm³. The muscle tissue volume of latissimus dorsi muscle in patients with lateral latissimus dysplasia was 172.2±97.8 cm³, only 57.1% of that in normal patients. In 49 patients with Poland Syndrome, the volume of latissimus dorsi muscle on the affected side was generally larger than that of pectoralis major muscle on the healthy side, with a volume difference of 33.8±63.9 cm³. The average volume of latissimus dorsi muscle on the affected side was less than that of pectoralis major muscle on the healthy side, and the difference between the two was -48.4±50.2 cm³. The average volume of latissimus dorsi muscle on the affected side was greater than that of pectoralis major muscle on the healthy side in 79.6% of patients, and the difference between the two was 54.8±48.4 cm³.

5. 49 patients with Poland Syndrome had an average diameter of 0.59±0.21mm of the beginning of the thoracodosal artery on the affected side and 0.61±0.17 mm on the healthy side, with no statistical difference between the affected and healthy side. In 65.3% of patients, the average diameter of the beginning of the affected side of the thoracodosal artery was greater than or equal to the average diameter of the beginning of the healthy side of the thoracodosal artery, with a difference of about 0.1mm. In 34.7% of patients, the average diameter of the beginning of the affected side of the thoracodosal artery was less than the average diameter of the beginning of the healthy side of the thoracodosal artery, with a difference of about 0.25mm. 8.1% of the patients had dysplasia at the beginning of the thoracodosal artery on the affected side. The average inner diameter of the dysplasia side was 0.9±0.25 mm, the average inner diameter of the normal side was 0.43±0.06 mm, and the difference of the average inner diameter between two sides was 0.47mm.

6. 28 patients, including 11 males and 17 females, received endoscopically assisted latissimus dorsi muscle transfer via the axillary incision to repair the chest wall malformation and reconstruct the breast. The area of transferred latissimus dorsi muscle flap was 437.2±110.0 cm² and the size of silicone prosthesis for breast reconstruction was 240.4±46.0 ml. It took 69.0±13.9 minute to harvest the latissimus dorsi muscle, 32.8±6.0 minute to create the anterior chest wall space endoscopically and the total operation time was 169.4±16.1 minute. The duration of drainage was 7.6±1.4 day. Two patients received contralateral endoscope-assisted prosthesis augmentation mammoplasty through axillary incision, and two patients received contralateral breast fat grafting. One patient had mild axillary wound dehiscence. One patient had seroma in the back after removal of drainages. Mild malposition of transferred latissimus dorsi flap was noted in one patient six months after surgery. The rest patients recovered well postoperatively without the following complications: muscle flap necrosis, hematoma, infection, transfer to open surgery, implant capsular contracture, implant malposition, implant rupture. The pain score gradually decreased daily after surgery within one week. The score of breast satisfaction and psychosocial well-being of female patients in breast-Q scale after surgery were significantly higher than those before surgery. All patients were satisfied with the results of surgery. The DASH score showed no significant impairment of upper limb function after surgery.

Conclusions

1. There were no significant differences in the length, volume and caliber of the vessels of the subclavian artery and its branches in the affected side and normal side in patients with Poland Syndrome and there was no correlation between the abnormalities of the subclavian artery and its branches and the severity of pectoralis major muscle defect. Therefore, the interruption of blood flow of the subclavian artery and its branches were probably not the cause of the thoracic malformation of Poland syndrome. The SASDS(Subclavian Artery Supply Disruption, SASDS) hypothesis was not able to explain the causes of chest malformation in Poland syndrome.

2. Three-dimensional CT reconstruction can accurately quantify pectoralis major defect and latissimus dorsi muscle in Poland Syndrome, which plays an important role in the selection of indications for pectoralis major reconstruction surgery using latissimus dorsi muscle flap. The thoracodosal artery of the affected side is normal in patients with Poland Syndrome, and in most patients the latissimus dorsi muscle is large enough to reconstruct the pectoralis major.

3. Endoscopy assisted latissimus dorsi transfer through axillary transverse incision provides a safe and effective method for chest wall reconstruction and breast reconstruction in patients with Poland syndrome, with good postoperative aesthetic effect, low complication rate and high patient satisfaction.