Long-term effectiveness of uncemented allograft-prosthesis composite for reconstruction of bone defects after proximal femur tumor resection / 中国修复重建外科杂志

OBJECTIVE@#To investigate the long-term effectiveness of uncemented allograft-prosthesis composite (APC) for reconstruction of bone defects after proximal femur tumor resection.@*METHODS@#Between June 2007 and March 2014, 21 patients who underwent uncemented APC reconstruction of proximal femur after tumor resection were retrospectively evaluated. There were 9 males and 12 females with an average age of 33.2 years (range, 19-54 years). There were 9 cases of giant cell tumor of bone, 5 cases of osteosarcoma, 4 cases of osteoblastic osteosarcoma, 2 cases of chondrosarcoma, and 1 case of undifferentiated pleomorphic sarcoma. Thirteen cases of benign bone tumors were all classified as stage 3 by Enneking staging; and 8 cases of malignant bone tumors were classified as grade ⅡB in 7 cases and grade ⅡA in 1 case according to the American Joint Committee on Cancer (AJCC) staging system. Among them, 7 patients underwent reoperation after recurrence, and the rest were primary operations; 8 patients presented with pathological fractures. The preoperative Harris hip score (HHS) and American Musculoskeletal Tumor Society (MSTS) score was 40 (30, 49) and 9.1±3.5, respectively. The length of osteotomy was 80-154 mm, with an average of 110 mm. At 1 year after operation and last follow-up, HHS and MSTS scores were utilized to evaluate the function of hip joint; the gluteus medius strength score was used to evaluation of the hip abduction function. Image examinations were taken at 1, 3, 6, 9, and 12 months after operation and every year thereafter to assess the union of allograft-host bone interfaces. Intra- and post-operative complications were also recorded.@*RESULTS@#All patients were followed up 84-163 months (mean, 123.5 months). At 1 year after operation and last follow-up, the HHS and MSTS scores significantly improved when compared with the preoperative scores ( P<0.05). However, there was no significant difference in the HHS score, MSTS score, and gluteus medius strength score between the two time points after operation ( P>0.05). Image examination showed that all allograft-host bone interfaces achieved union after 5-10 months (mean, 7.6 months). At last follow-up, all patients had bone resorption, including 11 severe cases, 4 moderate cases, and 6 mild cases; the bone resorption sites included Gruen 1, 2, and 7 regions. Complications included 10 fractures and 1 prosthetic fracture. Local recurrence occurred in 3 patients and pulmonary metastasis in 3 patients.@*CONCLUSION@#Uncemented APC is a reliable method for the reconstruction of bone defects after proximal femur tumor resection. It has the good long-term effectiveness and possesses obvious advantages in the union at the bone-bone surface.

Three-dimensional-printed hemi-pelvic prosthesis for revision of aseptic loosening or screw fracture of modular hemi-pelvic prosthesis / 中国修复重建外科杂志

OBJECTIVE@#To investigate the effectiveness of three-dimensional (3D)-printed hemi-pelvic prosthesis for revision of aseptic loosening or screw fracture of modular hemi-pelvic prosthesis.@*METHODS@#Between February 2017 and January 2020, 11 patients with aseptic loosening or screw fracture of modular hemi-pelvic prosthesis were revised using 3D-printed hemi-pelvic prostheses. There were 7 males and 4 females with an average age of 44 years (range, 25-60 years). In the first operation, all patients underwent total tumor resection, modular hemi-pelvic prosthesis reconstruction, and autologous femoral head transplantation. According to the Enneking pelvic partition system, 8 cases were resected in zones Ⅰ+Ⅱ and 3 cases in zones Ⅰ+Ⅱ+Ⅲ. The interval from the initial operation to this revision ranged from 14.3-66.2 months, with an average of 35.8 months. The operation time, the amount of intraoperative bleeding, and the occurrence of complications were recorded. At 6 months after the first operation, before revision, and at last follow-up, the American Musculoskeletal Tumor Society (MSTS) score and Harris score were used to evaluate the recovery of lower limb function. The pain-free walking distance of patients without brace assistance was recorded at last follow-up. X-ray films were taken at 1 month after the first operation, before revision, and at 1 month after revision, the acetabulum position was assessed by the differences in weight arm and cup height between bilateral hip joints. At last follow-up, the digital X-ray tomography was taken to evaluate the prosthesis-bone integration and the occurrence of aseptic loosening.@*RESULTS@#The operation time was 182.6-238.0 minutes (mean, 197.4 minutes). The amount of intraoperative bleeding was 400-860 mL (mean, 550.0 mL). All incisions healed by first intention with no infection, hip dislocation, nerve damage, or vascular-related adverse events. The MSTS score and Harris score at last follow-up were significantly higher than those at 6 months after the first operation and before revision ( P<0.05), while the score before revision was significantly lower than that at 6 months after the first operation ( P<0.05). At last follow-up, the patients were able to walk more than 1 000 meters painlessly without brace assistance. Imaging review showed that the difference of cup height at 1 month after revision was significantly lower than that at 1 month after the first operation and before revision, and at 1 month after the first operation than before revision operation, and the differences were significant ( P<0.05). There was no significant difference in the difference of weight arm among three time points ( P>0.05). All prostheses were well integrated, and no aseptic loosening of the prosthesis or screw fracture occurred.@*CONCLUSION@#Revision with 3D-printed hemi-pelvic prostheses benefited in reconstructing stable pelvic ring and natural bodyweight transmission for patients encountering the aseptic loosening or screw fracture of modular hemi-pelvic prosthesis. Early postoperative rehabilitation training can maximize the recovery of patient limb function, reduce pain during walking, and reduce the incidence of complications.

Mid-term effectiveness of hip preservation in the reconstruction of ultrashort bone segments in the proximal femur with three-dimensional printed customized cementless intercalary endoprosthesis with an intra-neck curved stem / 中国修复重建外科杂志

OBJECTIVE@#To explore the design points of a three-dimensional (3D) printed customized cementless intercalary endoprosthesis with an intra-neck curved stem and to evaluate the key points and mid-term effectiveness of its application in the reconstruction of ultrashort bone segments in the proximal femur.@*METHODS@#Between October 2015 and January 2021, 17 patients underwent reconstruction with a 3D printed-customized cementless intercalary endoprosthesis with an intra-neck curved stem. There were 11 males and 6 females, the age ranged from 10 to 76 years, with an average of 30.1 years. There were 9 cases of osteosarcoma, 4 cases of Ewing sarcoma, 2 cases of chondrosarcoma, 1 case of liposarcoma, and 1 case of myofibroblastoma. The disease duration was 5-14 months, with an average of 9.5 months. Enneking staging included 16 cases of stage ⅡB and 1 case of stage ⅢB. The distances from the center of the femoral head to the body midline and the acetabular apex were measured preoperatively on X-ray images. Additionally, the distances from the tip of the intra-neck curved stem to the body midline and the acetabular apex were measured at immediate postoperatively and last follow-up. The neck-shaft angle was also measured preoperatively, at immediate postoperatively, and at last follow-up. The status of osseointegration at the bone-prosthesis interface and bone growth into the prosthesis surface were assessed by X-ray films, CT, and Tomosynthesis-Shimadzu metal artefact reduction technology (T-SMART). The survival status of the patients, presence of local recurrence or distant metastasis, and occurrence of postoperative complications were assessed. The recovery of lower limb function was evaluated pre- and post-operatively using the Musculoskeletal Tumor Society (MSTS) scoring system, and pain relief was evaluated using the visual analogue scale (VAS) scores.@*RESULTS@#The patient's femoral resection length was (163.1±57.5) mm, the remaining proximal femoral length was (69.6±9.3) mm, and the percentage of femoral resection length/total femoral length was 38.7%±14.6%. All 17 patients were followed up 25-86 months with an average of 58.1 months. During the follow-up, 1 patient died of lung metastasis at 46 months postoperatively, and the remaining 16 patients survived tumor-free. There was no complication such as periprosthetic infection, delayed incision healing, aseptic loosening, prosthesis fracture, or periprosthetic fracture. No evidence of micromotion or wear around the implanted stem of the prosthesis was detected in X-ray and T-SMART evaluations. There was no significant radiolucent lines, and radiographic evidence of bone ingrowth into the bone-prosthesis interface was observed in all stems. There was no significant difference in the distance from the tip of the curved stem to the body midline and the apex of the acetabulum at immediate postoperatively and last follow-up compared with the distance from the center of the femoral head to the body midline and the apex of the acetabulum before operation, respectively (P>0.05), and there was no significant difference in the above indexes between immediate postoperatively and last follow-up (P>0.05). The differences in the neck-shaft angle at various time points before and after operation were also not significant (P>0.05). At last follow-up, the MSTS score was 26.1±1.2 and the VAS score was 0.1±0.5, which were significantly improved when compared with those before operation [19.4±2.1 and 5.7±1.0, respectively] (t=14.735, P<0.001; t=21.301, P<0.001). At last follow-up, none of the patients walked with the aid of crutches or other walkers.@*CONCLUSION@#The 3D printed customized cementless intercalary endoprosthesis with an intra-neck curved stem is an effective method for reconstructing ultrashort bone segments in the proximal femur following malignant tumor resection. The operation is reliable, the postoperative lower limb function is satisfactory, and the incidence of complications is low.

Short-term outcomes of reconstruction of tumorous critical bone defects at femoral shaft with a 3D printed ultra-short stem with a porous structure / 中华创伤骨科杂志

Objective:To explore the short-term outcomes of reconstruction of tumorous critical bone defects at femoral shaft with a 3D printed ultra-short stem with a porous structure.Methods:From September 2016 to June 2018, 8 patients underwent reconstruction of critical bone defects with a 3D printed ultra-short stem with a porous structure after resection of femoral shaft malignant tumor at Department of Orthopaedics, West China Hospital. There were 4 males and 4 females, with an average age of 36.9 years (from 11 to 61 years). Their preoperative Enneking staging was stage Ⅱb in all. There were 3 osteosarcomas, 2 Ewing sarcomas, 2 chondrosarcomas and one periosteal osteosarcoma. Preoperative CT/MRI image fusion technology was used to define the surgical boundary, design the guide plate and prosthesis, and perform surgical simulation. Tomosynthesis-shimadzu Metal Artefact Reduction technology was used to evaluate osseointegration. Complications and bone oncology prognosis of the patients were documented. The lower limb function of the patients was evaluated using Musculoskeletal Tumor Society (MSTS) 1993 scoring and knee range of motion.Results:The overall follow-up time ranged from 36 to 50 months, averaging 42.8 months. During operation one patient sustained a periprosthesis fracture, the union of which was followed up after wire assisted fixation. There was no local tumor recurrence, lung metastasis or death. The last follow-up revealed good osseointegration and basically isometric lower extremities in all cases. There was no such a complication as aseptic loosening of the prosthesis, deep infection or prosthesis fracture during the follow-up period. At the last follow-up in the 8 patients, the flexion range of the knee joint was 116.2°±9.1°, significantly improved compared with that before operation (98.8°±10.9°), and the MSTS score was (26.2±2.1) points, also significantly improved compared with that before operation [(21.6±1.8) points] ( P<0.05). Conclusions:Reconstruction with a 3D printed ultra-short stem with a porous structure is an accurate operation for femoral shaft tumorous bone defects. With careful preoperative design, intraoperative manipulation and strict postoperative follow-up management, this operation can lead to fine early curative outcomes for long shaft critical bone defects.

Replacement with 3D-printed custom-made hemipelvic prosthesis for primary malignancy involving the pubis / 中华创伤骨科杂志

Objective:To observe the short-term efficacy of 3D-printed custom-made hemipelvic prosthesis in the treatment of primary malignant bone tumors of the pubis.Methods:From June 2017 to May 2019, a total of 5 patients with pubic primary malignant tumor received type Ⅲ hemipelvectomy and reconstruction with a 3D-printed custom-made hemipelvic prosthesis at Department of Orthopedics, West China Hospital. They were 3 males and 2 females with an average age of 36.3 years (range, from 26 to 46 years). Of them, 3 underwent resection of the upper pubic ramus and 2 resection of both pubic rami. All their tumors were chondrosarcomas, with one case of Enneking stage Ⅱa and 4 cases of Enneking stage Ⅱb. Preoperative CT/MRI image fusion was used to determine the tumor-free resection margin, design guide templates for osteotomy and prosthesis, and simulate surgical procedures. A total of 5 3D-printed custom-made hemipelvic prostheses were designed, including 3 ones with an intramedullary stem to preserve partial pubis and 2 ones with a non-intramedullary stem not to preserve the pubis. The functional recovery was assessed by Musculoskeletal Tumor Society (MSTS) scores. The prosthetic position and osseointegration were evaluated by imaging examination. Oncological outcomes and complications were recorded.Results:R0 resection and precise reconstruction were accomplished in all patients. Their intraoperative blood loss ranged from 300 to 3, 700 mL (mean, 1, 680 mL), operation time from 180 to 430 min (mean, 294 min), and follow-up time from 13 to 29 months (mean, 20.6 months). All the 5 patients were alive with no evidence of disease or tumor recurrence. The functional MSTS scores at the final follow-up ranged from 29 to 31 (mean, 29.8). One male patient complained of erectile dysfunction. Fretting wear around the prosthetic stem was found in 3 patients while bone wear on the normal pubic side in 2. Osseointegration was observed in all patients with no complications like deep infection, prosthesis dislocation, prosthetic or screw breakage.Conclusion:Since 3D-printed custom-made hemipelvic prostheses can result in fine short-term efficacy for pubic primary malignant bone tumors, they may be a reliable method to reconstruct pelvic malignant tumors.

The medium-term outcomes of three-dimensional printing uncemented prosthesis replacement for giant cell tumor of distal radius / 中华骨科杂志

Objective To explain the concept and surgical technique of 3D printing uncement radius distal prosthesis,evaluate and discuss the medium-term outcome of the prosthesis for giant cell tumor in distal radius.Methods From September 2015 to March 2017,13 patients diagnosed as giant cell tumor in distal radius were performed with en bloc resection combined with 3D print uncement prosthesis.All patients graded Campanacci Ⅲ or occurred local recurrence.Two patients with local recurrence had a local lesion curettage,inactivation and bone cement filling.There were 7 males and 6 females,with an average age of 37.8 years.Through the preoperative three-dimensional CT data,the 3D model of the distal radius was obtained based on the contralateral radius and the 3D printing uncemented distal radius prosthesis was made.Directly reconstrucion was conducted if the wrist joint ligament and joint capsule can be preserved.The surrounding soft tissue,remaining joint ligament and joint capsule were sutured to the prosthesis together combined with a brace if the wrist joint ligament and joint capsule can be only preserved partially.Radiocarpal joint was temporarily fixed by Kuntscher pin if the wrist joint ligament and joint capsule can't be preserved completely.Results In our series,the average resection length of the distal radius measured from the radial styloid process was 65.54±6.70mm.The length of prosthesis was consistent with the resection length and the length ratio of prosthesis to prosthetic stem is 1:1.The follow-up time was 17.77±4.97 months.There were no local recurrence and metastasis.At the end of the followup,except waist flexion,the wrist extension,wrist pronation,wrist supination,hand grip strength and Mayo wrist were significantly improved from 41.69°± 11.35°,41.92°± 11.09°,40.00°±7.64°,16.84±6.28 mmHg,47.69±9.27 points preoperatively to 57.46°±17.18°,55.00°±17.91°,53.46°±19.30°,23.08±6.29 mmHg,70.00±11.55 points,respectively.The DASH score was significantly decreased from 32.07±6.71 points to 19.15±8.41 points postoperatively.During surgery,there was one patient received temporary wrist fixation with kirschner's needle,which got a relatively poor postoperative function.Excluding this patient,comparing the resuits of 8 cases with directly suturing of wrist joint ligament and joint capsule and that of 4 cases with reconstructing by suturing and fixing with a brace,there were no statistical differences.There were no wrist dislocation or subluxation,aseptic prosthesis loosening,wrist joint degenerative changes or other prosthesis related complications.Conclusion 33D printing uncemented distal radius prosthesis is a good choice for the Campanacci grade Ⅲ or recurrent giant cell tumor in distal radius,because of its personalized design and uncemented fixation;in clinical application,we should pay attention to the evaluation of preoperative wrist joint capsule and surrounding ligament and the intraoperative soft tissue repair techniques.