3D打印定制保留骨骺及关节面假体在青少年股骨原发恶性骨肿瘤大段骨缺损重建中的应用

Application of three-dimensional printed customized prosthesis with preserved epiphysis and articular surface in the reconstruction of large bone defects in treatment of adolescent femoral malignant tumors

目的 探讨3D打印定制保留骨骺及关节面假体在青少年股骨原发恶性骨肿瘤大段骨缺损重建中的临床应用及疗效。方法 回顾分析2020年1月—2021年10月符合选择标准的10例青少年股骨原发恶性骨肿瘤患者临床资料,均采用3D打印定制保留骨骺及关节面的干型假体行保肢手术治疗。其中男6例,女4例;年龄7~18岁,平均12.5岁。骨肉瘤8例,尤文肉瘤2例。Enneking分期均为Ⅱb期。病变长度76~240 mm,平均138.0 mm。截骨长度(即定制假体长度)为130~275 mm,平均198.5 mm;截骨远端与骺线距离0~15 mm,平均8.8 mm;瘤段骨截骨后骨缺损占病变骨全长37.36%~79.02%,平均49.43%。记录患者手术时间、术中出血量、并发症发生情况、肿瘤转归(参照RESIST1.1实体瘤疗效评价标准进行评价)及双下肢不等长情况;术后6个月采用肌肉骨骼肿瘤学会(MSTS)93评分进行功能评价,手术前后采用疼痛视觉模拟评分(VAS)进行疼痛评价。结果 10例患者手术均顺利实施,术后病理检查结果与术前活检病理检查结果相符。手术时间165~440 min,平均263 min;术中出血量100~800 mL,平均350 mL。所有患者均获随访,随访时间7~26个月,平均11.8个月。截骨面均未见肿瘤累及;定制假体均安装牢固,与保留关节面匹配紧密。肿瘤转归情况为4例疾病稳定、6例部分缓解。术后辅助化疗后9例均未发现局部复发或远处转移等情况;1例术后12个月发现肺部转移。术后14 d2例患者出现局部切口脂肪液化、切口浅表感染延迟愈合,1例术后7个月复查发现假体接触面局部骨质吸收情况,螺钉、假体均未松动;其余患者术后切口愈合良好,无感染及假体松动、断裂等并发症发生。术后6个月MSTS93评分为19~28分,平均24.1分;获优8例,良2例。VAS评分为(0.9±1.0)分,较术前(5.9±1.0)分明显改善,差异有统计学意义(t=23.717,P<0.001)。患者身高增长1~12 cm,平均4.6 cm。末次随访时,4例患者出现双下肢不等长,长度差为1 cm 2例,2 cm 2例。结论 3D打印假体应用于青少年股骨原发恶性骨肿瘤切除重建中可实现保留骨骺及关节面的目的,并取得良好临床疗效。

Objective To investigate the clinical application and effectiveness of three-dimensional(3D) printed customized prosthesis with preserved epiphysis and articular surface in the reconstruction of large bone defects in treatment of adolescent femoral malignant tumors.Methods The clinical data of 10 adolescent patients with femoral primary malignant tumor who met the selection criteria and underwent limb salvage surgery with 3D printed customized prosthesis with preserved epiphysis and articular surface between January 2020 and October 2021 were retrospectively analyzed.There were 6 males and 4 females with an average age of 12.5 years ranging from 7 to 18 years.There were 8 cases of osteosarcoma and 2 cases of Ewing’s sarcoma.Enneking stage was Ⅱb.The length of the lesions ranged from 76 to 240 mm,with an average of 138.0 mm.The length of osteotomy(i.e.length of customized prosthesis) ranged from 130 to 275 mm,with an average of 198.5 mm;the distance between distal osteotomy end and epiphyseal line ranged from 0 to 15 mm,with an average of 8.8 mm;the bone defect after osteotomy accounted for 37.36% to 79.02% of the total length of the lesion bone,with a mean of 49.43%.The operation time,intraoperative blood loss,complications,tumor outcome(refered to RESIST1.1 solid tumor efficacy evaluation criteria),and limb length discrepancy were recorded.The Musculoskeletal Cancer Society(MSTS) 93 score was used to evaluate the function at 6 months after operation,and visual analogue scale(VAS) score was used to evaluate the pain before and after operation.Results The operation was successfully performed in all the 10 patients,and the postoperative pathological results were consistent with the preoperative pathological results.The operation time was 165-440 minutes,with an average of 263 minutes;and the intraoperative blood loss was 100-800 mL,with an average of 350 mL.All patients were followed up 7-26 months,with an average of 11.8 months.No tumor was found on the osteotomy surface;the customized prosthesis were firmly installed and closely matched with the retained articular surface.The tumor outcome of neoadjuvant chemotherapy was stable in 4 cases and partial remission in 6 cases.No local recurrence or distant metastasis was found in 9 cases after postoperative adjuvant chemotherapy;pulmonary metastasis was found in 1 case at 12 months after operation.Two patients had local incision fat liquefaction,superficial infection,and delayed healing at 14 days after operation;1 patient had local bone absorption at the contact surface of the prosthesis,and the screw and prosthesis did not loosen at 7 months after operation;the other patients had good incision healing,with no infection,prosthesis loosening,fracture,or other complications.At 6 months after operation,the MSTS93 score was 19-28,with an average of 24.1;8 cases were excellent and 2 cases were good.The VAS score was 0.9±1.0,which significantly improved when compared with before operation(5.9±1.0)(t=23.717,P<0.001).The height of the patients increased by 1-12 cm,with an average of 4.6 cm.At last followup,4 patients had limb length discrepancy,with a length difference of 1 cm in 2 cases and 2 cm in 2 cases.Conclusion The application of 3D printed customized prosthesis in the resection and reconstruction of adolescents femoral primary malignant tumors can achieve the purpose of preserving epiphysis and articular surface,and obtain good effectiveness.