Do Massive Allograft Reconstructions for Tumors of the Femur and Tibia Survive 10 or More Years after Implantation?

BACKGROUND: Massive bone allografts have been used for limb salvage in patients undergoing bone tumor resections as an alternative to endoprostheses. Although several studies on massive allograft reconstructions for bone tumors reported that most complications occur in the first 3 years after surgery, there are no long-term reports on complications to substantiate this contention. We believe such information is important so that surgeons and patients can make more informed decisions when choosing a reconstructive method after tumor resection. QUESTIONS/PURPOSES: (1) What is the survival of allografts free from removal, amputation, or joint replacement in patients treated for bone tumors in the lower limb with a minimum of 10 years of followup? (2) What complications occur after 10 or more years of followup? (3) Are there factors associated with allograft survival, such as age, sex, the affected bone, reconstruction type (intercalary or osteoarticular allograft), tumor type (malignant or benign), failure type, and chemotherapy use? METHODS: We retrospectively analyzed the records of 398 patients treated in one center with benign or malignant bone tumors in the femur or tibia between 1986 and 2007. During the period in question, our general indications for using allografts (354 patients) included patients with benign or low-grade sarcomas and patients with high-grade sarcomas with clinical and imaging response to neoadjuvant chemotherapy. Other approaches such as endoprostheses (44 patients) were indicated if the patient received radiotherapy, in patients with high-grade sarcomas without clinical and imaging response to neoadjuvant chemotherapy, or with neurovascular tumor involvement. We excluded from the analysis 53 patients treated with allograft-prosthetic composites, 46 with hemicondylar osteoarticular allografts, and 57 with intercalary hemicylindrical allografts. The study was thus performed in 198 patients treated with segmental massive allografts in the long bones of the lower extremity (132 femurs and 66 tibias) after resection of a primary bone tumor, including 120 patients treated with osteoarticular and 78 with segmental intercalary allografts. A total of 32 (16%) of the 198 patients died before 10 years, and graft status was known in all of those patients; these patients were included (mean followup, 192 months; range, 1-370 months). All remaining 166 patients who were not known to have died before 10 years were accounted for at least 10 years after the allograft procedure (mean, 222 months; range, 120-370 months). No patient was lost to followup. The mean age was 22 years (range, 2-55 years); 105 patients were male (53%) and 93 were female. The predominant diagnoses were osteosarcoma (n = 125, 63%), giant cell tumor of bone (n = 27, 14%), and Ewing's sarcoma (n = 19, 10%). In all, 146 patients (74%) underwent chemotherapy. Selected variables were analyzed using multivariate logistic regression analyses to identify risk factors of allograft removal, joint replacement, or amputation. We performed competitive risk analysis with allograft removal, joint replacement, or amputation as the endpoint at 5, 10, and 20 years. Patient function was evaluated using the Musculoskeletal Tumor Society (MSTS)-93 scoring system. RESULTS: The risk of allograft removal, joint replacement, or amputation was 36% at 5 years (95% CI, 30-43), 40% at 10 years (95% CI, 33-47), and 44% at 20 years (95% CI, 37-51). Fractures occurred in 15% (29 patients), infection in 14% (27 patients), nonunion in 12% (23 patients) and tumor recurrence in 7% (13 patients). Thirty-two patients died of disease before 10 years; nine of these patients had a second surgery before death, eight had an amputation, and one underwent graft removal. Of the 166 patients who were still alive 10 years after the allograft procedure, 36 underwent allograft removal, six patients underwent joint replacement, and four had an amputation; however, after 10 years, six more allografts were removed (four due to fractures, one due to infection, and one due to instability), and another patient was amputated due to a second malignancy. After controlling for potentially confounding variables including death, we found that the risk of allograft removal, joint replacement, or amputation in osteoarticular tibial grafts (58% [95% CI, 43-73] at 5, 10, and 20 years) was higher than that of osteoarticular femur allografts (29% [95% CI, 18-39] at 5 years, 30% [95% CI, 19-40] at 10 years, 37% [95% CI, 25-48] at 20 years; p = 0.010) and tibia intercalary allografts (26% [95% CI, 7-45] at 5, 10 and 20 years; p = 0.020). Fractures occurred more frequently in the femur (18% [95% CI, 11-25]) than in the tibia (5% [95% CI, 0-10]; p < 0.010), and infections occurred more frequently in the tibia (24% [95% CI, 14-35]) than in the femur (4% [95% CI, 0-8]; p < 0.001). With the number of patients we had, we found no difference in the proportion of local recurrence in the tibia (12% [95% CI, 4-20]) compared with the femur (5% [95% CI, 1-9]; p < 0.053). CONCLUSIONS: Infections were the most common complications associated with allograft removal in the first 2 to 3 years after reconstruction and were more frequently associated with tibial allograft removal. Fractures were more commonly associated with graft removal with longer term followup and were more frequently associated with femoral allograft removal. Although we cannot directly compare our results with other types of reconstructions, we believe that allografts still have a role in the reconstruction of patients with a benign or low-grade bone tumor. Future studies in femoral allograft with longer followup should be performed to analyze factors that may explain why some grafts fail, such as the percent of the length of the bone resected, type and number of plates and screws used and type of fixation (rods versus plates). There was a higher incidence of graft removal in patients with proximal tibia osteoarticular allografts, which has led us to use this type of reconstruction only in pediatric patients over the last 15 years. LEVEL OF EVIDENCE: Level III, therapeutic study.

Does Osteoarticular Allograft Reconstruction Achieve Long-term Survivorship after En Bloc Resection of Grade 3 Giant Cell Tumor of Bone?

BACKGROUND: En bloc resection of benign tumors is only indicated in aggressive lesions with substantial destruction of the affected bone. Few reports have evaluated the long-term outcome of Grade 3 giant cell tumor of bone (GCTB; defined as severe bone destruction and soft tissue extension) treated with en bloc resection and reconstruction with a massive allograft. We recently reported that patients with benign tumors achieved better allograft reconstruction survivorship compared with those treated for a malignant bone tumor. In light of that finding, we wondered whether osteoarticular allografts would be a viable long-term alternative for Grade 3 GCTB, which could be important in some countries because of greater availability and lower costs compared with endoprostheses. QUESTIONS/PURPOSES: We analyzed a group of patients with Grade 3 GCTBs treated with en bloc resection and osteoarticular allograft reconstruction in terms of (1) survivorship free from allograft removal at 10 years; (2) survivorship free from reoperation for any reason at 10 years, (3) functional results as measured by the Musculoskeletal Tumor Society (MSTS) score, (4) assessment of arthrosis at the knee. METHODS: We retrospectively analyzed all patients with a Grade 3 GCTB treated between 1980 and 2007. Only patients treated with en bloc resection and reconstruction with massive osteoarticular allografts were included in the analysis. The indication for osteoarticular reconstruction during that time included severe bone destruction with intraarticular compromise of the tumor, intraarticular fracture because of tumor growth, the presence of inadequate remaining subchondral bone to resist normal loading (for the distal femur or proximal tibia), and the preservation of a soft-tissue component (ligaments or meniscus) for articular stability. During the period, 75 patients were treated with en bloc resection. Patients treated with intralesional curettage (n = 7), reconstruction with an endoprosthesis (n = 2), intercalary arthrodesis (n = 13), or unicondylar reconstruction (n = 14) were excluded. Of the original 75 treated with en bloc resection, 52% (39) were treated with osteoarticular allograft reconstruction, and no patient was lost to follow-up before 2 years or had substantial missing data. However, of the 39 patients, another 21% (8) have not been seen in the last 5 years, but these were included here because they reached the 10-year minimum surveillance period before being lost. Twenty-three of those 39 patients were previously reported by our group and 16 new patients (treated between 1980-1985) were included in this series (eight distal radius, six distal femur, two proximal tibias), extending the follow-up period and including more patients for analysis. The median (range) follow-up duration was 26 years (10 to 34). We assessed survivorship using a Kaplan-Meier analysis, we drew MSTS scores retrospectively from patients´ medical records, and we graded arthrosis using the Ahlbäck scale for the knee (which was by far the most common joint involved, n = 31, and so it was the joint we assessed for the presence of arthrosis). RESULTS: The survivorship free from allograft removal was 85% at 10 years (95% CI 74 to 96). The allograft survivorship free from reoperation for any reason at 10 years was 72% (95% CI 59 to 87). The median (range) MSTS score was 28 points (19 to 30). The grade of arthrosis in the knee at last follow-up was analyzed in 20 patients and classified in nine as Ahlbäck Type 4, in six as Type 3, in three as Type 2 and in two as Type 5. CONCLUSIONS: Osteoarticular allograft reconstruction after a Grade 3 GCTB en bloc resection showed excellent long-term survivorship. We believe these results compare favorably with other studies on endoprosthetic reconstruction and head-to-head studies of these approaches should be performed; these would need to be multicenter trials. In the meantime, in locations where endoprostheses are unavailable or too expensive, we believe our results support the use of osteoarticular allografts. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Pediatric Chondroblastoma and the Need for Lung Staging at Presentation.

PURPOSE: Chondroblastoma is a benign, but potentially locally aggressive, bone tumor with predilection for the epiphysis of long bones in growing children. Historically, there is a reported 2% risk of lung metastasis, however these cases are mostly in the form of isolated single reports and the vast majority in adults. The purpose of this study was to identify the "true" risk of lung metastases at presentation in skeletally immature patients with a benign chondroblastoma, and therefore revisit the need for routine chest staging. METHODS: This was a multi-institution, international retrospective study of children and adolescents diagnosed and treated for a benign chondroblastoma. We focused on the screening and diagnosis of lung metastasis, type of staging utilized and the incidence of local recurrence. Detailed review of the available literature was also performed for comparison. RESULTS: The final studied cohort included 130 children with an average age of 14.5 years (range: 6 to 18 y). There were 94 boys and 36 girls. Lesions more often involved the proximal humerus (32/130), proximal tibia (30/130), and proximal femur (28/130). At an average follow-up of 50 months, there were 15 local recurrences (11% rate) and no cases of lung metastasis. All patients underwent chest imaging at presentation. The overall reported lung metastases rate in the pulled literature review (larger series only) was 0.4% (7/1625), all patients were skeletally mature. CONCLUSIONS: This is the largest cohort of pediatric-exclusive chondroblastoma in the literature. Despite minor differences in management between the centers included, the recurrence rate was similar and there was no evidence of lung metastasis (0 in 130). The incidence of distant involvement in a true benign chondroblastoma in children is much lower than the 2% previously reported in the literature, and the need for routine chest staging should be revisited. LEVEL OF EVIDENCE: Level III.

What Are the Complications of Allograft Reconstructions for Sarcoma Resection in Children Younger Than 10 Years at Long-term Followup?

BACKGROUND: Preservation of limb function after resection of malignant bone tumors in skeletally immature children is challenging. Resection of bone sarcomas and reconstruction with an allograft in patients younger than 10 years old is one reconstructive alternative. However, long-term studies analyzing late complications and limb length discrepancy at skeletal maturity are scarce; this information would be important, because growth potential is altered in these patients owing to the loss of one physis during tumor resection. QUESTIONS/PURPOSES: At a minimum followup of 10 years after reconstructions in children younger than 10 years of age at the time of reconstruction, we asked what is (1) the limb length discrepancy at skeletal maturity and how was it managed; (2) the risk of amputation; (3) the risk of allograft removal; and (4) the risk of second surgery resulting from complications? METHODS: Between 1994 and 2006, we performed 22 bone allografts after bone sarcoma resections in children younger than 10 years of age. Of those, none were lost to followup before the minimum followup of 10 years was reached, and an additional six had died of disease (of whom three died since our last report on this group of patients), leaving 16 patients whom we studied here. Followup on these patients was at a mean of 13.5 years (range, 10-22 years). During the period in question, no other treatments (such as extendible prostheses, amputations, etc) were used. The mean age at the time of the original surgery was 7 years (range, 2-10 years), and the mean age of the 16 alive patients at last followup was 20 years (range, 15-28 years). This series included 10 boys and six girls with 14 osteosarcomas and two Ewing sarcomas. Ten reconstructions were performed with an intercalary allograft and six with an osteoarticular allograft. The growth plate was uninvolved in three patients, whereas in the remaining 13, the growth plate was included in the resection (seven intercalary and six osteoarticular allografts). Limb length discrepancy at skeletal maturity was measured with full-length standing radiographs, and data were collected by retrospective study of a longitudinally maintained institutional database. The risk of amputation, allograft removal, and secondary surgery resulting from a complication was calculated by a competing-risk analysis method. RESULTS: We observed no limb length discrepancy at skeletal maturity in the three patients with intercalary resections in whom we preserved the physes on both sides of the joint (two femurs and one tibia); however, one patient developed malalignment that was treated with corrective osteotomy of the tibia. The remaining 13 patients developed limb length discrepancy as a result of loss of one physis. Seven patients (four femurs, two tibias, and one humerus) developed shortening of ≤ 3 cm (mean, 2.4 cm; range, 1-3 cm) and no lengthening was performed. Six patients developed > 3 cm of limb discrepancy at skeletal maturity (all distal femoral reconstructions). In four patients this was treated with femoral lengthening, whereas two declined this procedure (each with 6 cm of shortening). In the four patients who had a lengthening procedure, one patient had a final discrepancy of 4 cm, whereas the other three had equal limb lengths at followup. The risk of amputation was 4% (95% confidence interval [CI], 0-15) and none occurred since our previous report. The risk of allograft removal was 15% (95% CI, 1-29) and none occurred since our previous report on this group of patients. The risk of other operations resulting from a complication was 38% (95% CI, 19-57). Eleven patients underwent a second operation resulting from a complication (three local recurrences, five fractures, one infection, one nonunion, and one tibial deformity), of which three were performed since our last report on this group of patients. CONCLUSIONS: Limb length inequalities and subsequent procedures to correct them were common in this small series of very young patients as were complications resulting in operative procedures, but overall most allografts remained in place at long-term followup. In skeletally immature children, bone allograft is one alternative among several that are available (such as rotationplasty and endoprosthesis), and future studies with long followup may be able to compare the available options with one another. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Is Navigation-guided En Bloc Resection Advantageous Compared With Intralesional Curettage for Locally Aggressive Bone Tumors?

BACKGROUND: The treatment of locally aggressive bone tumors is a balance between achieving local tumor control and surgical morbidity. Wide resection decreases the likelihood of local recurrence, although wide resection may result in more complications than would happen after curettage. Navigation-assisted surgery may allow more precise resection, perhaps making it possible to expand the procedure's indications and decrease the likelihood of recurrence; however, to our knowledge, comparative studies have not been performed. QUESTIONS/PURPOSES: The purpose of this study was to compare curettage plus phenol as a local adjuvant with navigation-guided en bloc resection in terms of (1) local recurrence; (2) nononcologic complications; and (3) function as measured by revised Musculoskeletal Tumor Society (MSTS) scores. METHODS: Patients with a metaphyseal and/or epiphyseal locally aggressive primary bone tumor treated by curettage and adjuvant therapy or en bloc resection assisted by navigation between 2010 and 2014 were considered for this retrospective study. Patients with a histologic diagnosis of a primary aggressive benign bone tumor or low-grade chondrosarcoma were included. During this time period, we treated 45 patients with curettage of whom 43 (95%) were available for followup at a minimum of 24 months (mean, 37 months; range, 24-61 months), and we treated 26 patients with navigation-guided en bloc resection, of whom all (100%) were available for study. During this period, we generally performed curettage with phenol when the lesion was in contact with subchondral bone. We treated tumors that were at least 5 mm from the subchondral bone, such that en bloc resection was considered possible with computer-assisted block resection. There were no differences in terms of age, gender, tumor type, or tumor location between the groups. Outcomes, including allograft healing, nonunion, tumor recurrence, fracture, hardware failure, infection, and revised MSTS score, were recorded. Bone consolidation was defined as complete periosteal and endosteal bridging visible between the allograft-host junctions in at least two different radiographic views and the absence of pain and instability in the union site. All study data were obtained from our longitudinally maintained oncology database. RESULTS: In the curettage group, two patients developed a local recurrence, and no local recurrences were recorded in patients treated with en bloc resection. All patients who underwent navigation-guided resection achieved tumor-free margins. Intraoperative navigation was performed successfully in all patients and there were no failures in registration. Postoperative complications did not differ between the groups: in patients undergoing curettage, 7% (three of 43) and in patients undergoing navigation, 4% (one of 26) had a complication. There was no difference in functional scores: mean MSTS score for patients undergoing curettage was 28 points (range, 27-30 points) and for patients undergoing navigation, 29 (range, 27-30 points; p = 0.10). CONCLUSIONS: In this small comparative series, navigation-assisted resection techniques allowed conservative en bloc resection of locally aggressive primary bone tumors with no local recurrence. Nevertheless, with the numbers available, we saw no difference between the groups in terms of local recurrence risk, complications, or function. Until or unless studies demonstrate an advantage to navigation-guided en bloc resection, we cannot recommend wide use of this novel technique because it adds surgical time and expense. LEVEL OF EVIDENCE: Level III, therapeutic study.

Is Needle Biopsy Clinically Useful in Preoperative Grading of Central Chondrosarcoma of the Pelvis and Long Bones?

BACKGROUND: Central chondrosarcoma of bone is graded on a scale of 1 to 3 according to histological criteria. Clinically, these tumors can be divided into low-grade (Grade 1) and high-grade (Grade 2, Grade 3, and dedifferentiated) chondrosarcomas. Although en bloc resection has been the most widely used treatment, it has become generally accepted that in selected patients with low-grade chondrosarcomas of long bones, curettage is safe and effective. This approach requires an accurate preoperative estimation of grade to avoid under- or overtreatment, but prior reports have indicated that both imaging and biopsy do not always give an accurate prediction of grade. QUESTIONS/PURPOSES: (1) What is the concordance of image-guided needle preoperative biopsy and postoperative grading in central (intramedullary) chondrosarcomas of long bones, and how does this compare with the concordance of image-guided needle preoperative biopsy and postoperative grading in central pelvic chondrosarcomas? (2) What is the concordance of preoperative image-guided needle biopsy and postoperative findings in differentiating low-grade from high-grade central chondrosarcomas of long bones, and how does this compare with the concordance in central pelvic chondrosarcomas? METHODS: Between 1997 and 2014, in our institution, we treated 126 patients for central chondrosarcomas located in long bones and the pelvis. Of these 126 cases, 41 were located in the pelvis and the remaining 85 cases were located in long bones. This study considers 39 (95%) and 40 (47%) of them, respectively. We included all cases in which histological information was complete regarding preoperative and postoperative tumor grading. We excluded all cases with incomplete data sets or nondiagnostic preoperative biopsies. To evaluate the needle biopsy accuracy, we compared the histological tumor grade, obtained from the preoperative biopsy, with the final histological grade obtained from the postoperative surgical specimen. The weighted and nonweighted kappa statistics were used to evaluate the agreement. RESULTS: Concordance between the preoperative biopsy and the final pathological analysis in terms of histological grade was much higher in long-bone chondrosarcoma than in pelvic chondrosarcoma (83% [33 of 40] versus 36% [14 of 39]; odds ratio, 8, 48). Likewise, the weighted kappa coefficients were higher in long-bone chondrosarcoma than in pelvic chondrosarcoma for the determination of histological grade (0.63; 95% confidence interval [CI], 0.34-0.91 versus 0.12; -0.32 to 0.57; p < 0.001). When categorizing the lesions as low grade or high grade, concordance between the preoperative biopsy and the final pathological analysis was much higher in long-bone chondrosarcoma than in pelvic chondrosarcoma (90% [36 of 40] versus 67% [26 of 39]; odds ratio, 4, 5). Likewise, the weighted kappa coefficients were higher in long-bone chondrosarcoma than in pelvic chondrosarcoma (0.73; 95% CI, 0.51-0.94 versus 0.26; 0.04-0.48; p < 0.001). CONCLUSIONS: Image-guided needle biopsy, when performed by a specialist radiologist and evaluated by an experienced bone pathologist, is a useful tool in determining the histological grade of long-bone chondrosarcomas allowing identification of true low-grade tumors. The histological grade should be correlated with imaging and the clinical presentation, but under these circumstances, experienced tumor surgeons may use this information in planning surgical treatment. The same appears not to be true for pelvic lesions, in which histological grade established by needle biopsy should be interpreted with caution. LEVEL OF EVIDENCE: Level III, diagnostic study.

What Happens to the Articular Surface After Curettage for Epiphyseal Chondroblastoma? A Report on Functional Results, Arthritis, and Arthroplasty.

BACKGROUND: Chondroblastoma is an uncommon, benign, but locally aggressive bone tumor that occurs in the apophyses or epiphyses of long bones, primarily in young patients. Although some are treated with large resections, aggressive curettage and bone grafting are more commonly performed to preserve the involved joint. Such intralesional resection may result in damage to the growth plate and articular cartilage, which can result in painful arthritis. Prior studies have focused primarily on oncologic outcomes rather than long-term joint status and functional outcomes. QUESTIONS/PURPOSES: (1) What local complications can be expected after aggressive intralesional curettage of epiphyseal chondroblastoma? (2) What is the joint survival of a joint treated in this way for chondroblastoma? (3) What additional procedures are used in treating symptomatic joint osteoarthritis after treatment of the chondroblastoma? (4) What are the functional outcomes in this group of patients? METHODS: A retrospective study of our prospectively collected database between 1975 and 2013 was done. We found 64 patients with a diagnosis of chondroblastoma of bone. After applying our selection criteria, 53 patients were involved in this study. We excluded seven patients with tumors initially treated with en bloc resection (five located in the extremities and two in the axial skeleton) and two patients with apophyseal tumors. One patient who underwent nonsurgical treatment and one patient lost to followup were also excluded. The mean age was 18 years (range, 11-39 years); the minimum followup was 2 years with a mean followup 77 months (range, 24-213 months). We analyzed all patients with a diagnosis of epiphyseal chondroblastoma of the limb treated with aggressive curettage and joint preservation surgery. During the period in question, our general indications for curettage were patients with active, painful tumors and those with more aggressive ones that remained intracompartmental, whereas initial wide en bloc resection was indicated in patients who had tumors with an extracompartmental extension breaching the adjacent joint cartilage and massive articular destruction. The tumor location was the distal femur in 14 patients, proximal tibia in 11, proximal humerus in 10, proximal femur in eight, the talus in seven, and elsewhere in the lower extremity in three. Local complications including joint degeneration and tumor recurrence were evaluated. Based on radiographic analysis, secondary osteoarthritis was classified by using the Kellgren-Lawrence grading system from Grade 0 to Grade IV. Patients who underwent joint replacement resulting from advanced symptomatic osteoarthritis were considered to have had joint failure for purposes of survivorship analysis, which was estimated using the Kaplan-Meier method. Functional results were evaluated with the Musculoskeletal Tumor Society functional score by the treating surgeon, who transcribed the results on the digital records every 6 months of followup. RESULTS: Twenty-two patients (42%) developed 26 local complications. The most common local complication was osteoarthritis in 20 patients (77% [20 of 26 complications]); tumor recurrence was observed in four patients; an intraarticular fracture and superficial infection treated with surgical débridement and antibiotics developed in one patient each. Joint survival was 90% at 5 years (95% confidence interval [CI], 76%-100%) and 74% at 10 years (95% CI, 48%-100%). Proximal femoral tumor location was associated with lower survivorship of the joint than other locations showing a 5-year survival rate of 44% (95% CI, 0%-88%; p = 0.000). Of the 20 patients with osteoarthritis, four were symptomatic enough to undergo joint replacement, all of which were for tumors in the proximal femur. The mean Musculoskeletal Tumor Society functional score was 28 of 30 points (93%). CONCLUSIONS: Osteoarthritis was a frequent complication of aggressive curettage of epiphyseal chondroblastoma, and tumors located in the proximal femur appeared to be at particular risk of secondary osteoarthritis and prosthetic replacement. Because chondroblastoma is a tumor that disproportionately affects younger patients, the patient and surgeon should be aware that arthroplasty at a young age is a potential outcome for treatment of proximal femoral chondroblastomas. LEVEL OF EVIDENCE: Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

What Is the Expected Learning Curve in Computer-assisted Navigation for Bone Tumor Resection?

BACKGROUND: Computer navigation during surgery can help oncologic surgeons perform more accurate resections. However, some navigation studies suggest that this tool may result in unique intraoperative problems and increased surgical time. The degree to which these problems might diminish with experience-the learning curve-has not, to our knowledge, been evaluated for navigation-assisted tumor resections. QUESTIONS/PURPOSES: (1) What intraoperative technical problems were observed during the first 2 years using navigation? (2) What was the mean time for navigation procedures and the time improvement during the learning curve? (3) Have there been any differences in the accuracy of the registration technique that occurred over time? (4) Did navigation achieve the goal of achieving a wide bone margin? METHODS: All patients who underwent preoperative virtual planning for tumor bone resections and operated on with navigation assistance from 2010 to 2012 were prospectively collected. Two surgeons (GLF, LAA-T) performed the intraoperative navigation assistance. Both surgeons had more than 5 years of experience in orthopaedic oncology with more than 60 oncology cases per year per surgeon. This study includes from the very first patients performed with navigation. Although they did not take any formal training in orthopaedic oncology navigation, both surgeons were trained in navigation for knee prostheses. Between 2010 and 2012, we performed 124 bone tumor resections; of these, 78 (63%) cases were resected using intraoperative navigation assistance. During this period, our general indications for use of navigation included pelvic and sacral tumors and those tumors that were reconstructed with massive bone allografts to obtain precise matching of the host and allograft osteotomies. Seventy-eight patients treated with this technology were included in the study. Technical problems (crashes) and time for the navigation procedure were reported after surgery. Accuracy of the registration technique was defined and the surgical margins of the removed specimen were determined by an experienced bone pathologist after the surgical procedure as intralesional, marginal, or wide margins. To obtain these data, we performed a chart review and review of operative notes. RESULTS: In four patients (of 78 [5%]), the navigation was not completed as a result of technical problems; all occurred during the first 20 cases of the utilization of this technology. The mean time for navigation procedures during the operation was 31 minutes (range, 11-61 minutes), and the early navigations took more time (the regression analysis shielded R2 = 0.35 with p < 0.001). The median registration error was 0.6 mm (range, 0.3-1.1 mm). Registration did not improve over time (the regression analysis slope estimate is -0.014, with R2 = 0.026 and p = 0.15). Histological examinations of all specimens showed a wide bone tumor margin in all patients. However, soft tissue margins were wide in 58 cases and marginal in 20. CONCLUSIONS: We conclude that navigation may be useful in achieving negative bony margins, but we cannot state that it is more effective than other means for achieving this goal. Technical difficulty precluded the use of navigation in 5% of cases in this series. Navigation time decreased with more experience in the procedure but with the numbers available, we did not improve the registration error over time. Given these observations and the increased time and expense of using navigation, larger studies are needed to substantiate the value of this technology for routine use. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Proximal Tibia Reconstruction After Bone Tumor Resection: Are Survivorship and Outcomes of Endoprosthetic Replacement and Osteoarticular Allograft Similar?

BACKGROUND: The proximal tibia is one of the most challenging anatomic sites for extremity reconstructions after bone tumor resection. Because bone tumors are rare and large case series of reconstructions of the proximal tibia are lacking, we undertook this study to compare two major reconstructive approaches at two large sarcoma centers. QUESTIONS/PURPOSES: The purpose of this study was to compare groups of patients treated with endoprosthetic replacement or osteoarticular allograft reconstruction for proximal tibia bone tumors in terms of (1) limb salvage reconstruction failures and risk of amputation of the limb; (2) causes of failure; and (3) functional results. METHODS: Between 1990 and 2012, two oncologic centers treated 385 patients with proximal tibial resections and reconstruction. During that time, the general indications for those types of reconstruction were proximal tibia malignant tumors or bone destruction with articular surface damage or collapse. Patients who matched the inclusion criteria (age between 15 and 60 years old, diagnosis of a primary bone tumor of the proximal tibia treated with limb salvage surgery and reconstructed with endoprosthetic replacement or osteoarticular allograft) were included for analysis (n = 149). In those groups (endoprosthetic or allograft), of the patients not known to have reached an endpoint (death, reconstructive failure, or limb loss) before 2 years, 85% (88 of 104) and 100% (45 of 45) were available for followup at a minimum of 2 years. A total of 88 patients were included in the endoprosthetic group and 45 patients in the osteoarticular allograft group. Followup was at a mean of 9.5 (SD 6.72) years (range, 2-24 years) for patients with endoprosthetic reconstructions, and 7.4 (SD 5.94) years for patients treated with allografts (range, 2-21 years). The following variables were compared: limb salvage reconstruction failure rates, risk of limb amputation, type of failures according to the Henderson et al. classification, and functional results assessed by the Musculoskeletal Tumor Society system. RESULTS: With the numbers available, after competitive risk analysis, the probability of failure for endoprosthetic replacement of the proximal tibia was 18% (95% confidence interval [CI], 10.75-27.46) at 5 years and 44% (95% CI, 31.67-55.62) at 10 years and for osteoarticular allograft reconstruction was 27% (95% CI, 14.73-40.16) at 5 years and 32% (95% CI, 18.65-46.18) at 10 years. There were no differences in terms of risk of failures at 5 years (p = 0.26) or 10 years (p = 0.20) between the two groups. Fifty-one of 88 patients (58%) with proximal tibia endoprostheses developed a reconstruction failure with mechanical causes being the most prevalent (32 of 51 patients [63%]). A total of 19 of 45 osteoarticular allograft reconstructions failed (42%) and nine of 19 (47%) of them were caused by early infection. Ten-year risk of amputation after failure for endoprosthetic reconstruction was 10% (95% CI, 5.13-18.12) and 11% (95% CI, 4.01-22.28) for osteoarticular allograft with no difference between the groups (p = 0.91). With the numbers available, there were no differences between the groups in terms of the mean Musculoskeletal Tumor Society score (26.58, SD 2.99, range, 19-30 versus 27.52, SD 1.91, range, 22-30; p = 0.13; 95% CI, -2,3 to 0.32). Mean extension lag was more severe in the endoprosthetic group than the osteoarticular allograft group: 13.56° (SD 18.73; range, 0°-80°) versus 2.41° (SD 5.76; range, 0°-30°; p < 0.001; 95% CI, 5.8-16.4). CONCLUSIONS: Reconstruction of the proximal tibia with either endoprosthetic replacement or osteoarticular allograft appears to offer similar reconstruction failures rates. The primary cause of failure for allograft was infection and for endoprosthesis was mechanical complications. We believe that the treating surgeon should have both options available for treatment of patients with malignant or aggressive tumors of the proximal tibia. (S)he might consider an allograft in a younger patient to achieve better extensor mechanism function, whereas in an older patient or one with a poorer prognosis where return to function and ambulation quickly is desired, an endoprosthesis may be advantageous. LEVEL OF EVIDENCE: Level III, therapeutic study.

What Are the Risk Factors and Management Options for Infection After Reconstruction With Massive Bone Allografts?

BACKGROUND: Massive bone allografts have been used for limb salvage of bone tumor resections as an alternative to endoprosthesis, although they have different outcomes and risks. The use of massive bone allografts has been thought to be associated with a high risk for infection, and there is no general consensus on the management of this complication and final outcome. Because infection is such a devastating complication of limb salvage, at times leading to loss of a limb, recognizing the risk factors for infection and the results of treatment is important. QUESTIONS/PURPOSES: The purposes of this study were (1) to analyze the frequency of infection in a group of patients treated with massive bone allografts; (2) to analyze risk factors such as age, sex, affected bone, type of reconstruction, operative room used, primary or revision procedure, length of postoperative antibiotic administration, and use of chemotherapy; and (3) to determine the likelihood that treatment of an infected allograft will result in a successful reconstruction. METHODS: We retrospectively analyzed the records of patients treated with massive bone allografts for a benign or malignant bone tumor or as a revision for a previous limb salvage procedure between 1985 and 2011. During this period, 673 patients were reconstructed with massive bone allografts in long bones, which included 272 osteoarticular, 246 intercalary, and 155 allograft-prosthetic composite reconstructions. Using a chart review, we ascertained the frequency of infection and reoperations after the treatment of infected allografts. Minimum followup was 2 years unless death occurred earlier (mean, 106 months; range, 6-360 months), and no patient was lost to followup. The selected variables were analyzed using multivariate logistic regression to identify risk factors for infection. We analyzed survivorship free of infection as the endpoint. RESULTS: During followup, 60 patients (9%) had a bacterial infection of the allograft with a survivorship free from infection of 92% at 5 years (95% confidence interval [CI], 90%-94%) and 91% at 10 years (95% CI, 89%-93%). We found that tibia allografts (p < 0.001; odds ratio [OR], 3.17; 95% CI, 1.80-5.60), male patients (p < 0.029; OR, 1.92; 95% CI, 1.08-3.49), procedures performed in a conventional operating room (p < 0.002; OR, 3.15; 95% CI, 1.58-6.62), and the use of longer periods of postoperative antibiotics (p < 0.041; OR, 2.25; 95% CI, 1.02-4.88) were patient factors associated with a greater risk of infection. In 11 patients (18%, 11 of 60 infections) the infection was controlled with antibiotics and surgical débridement; however, in 49 patients (82%, 49 of 60 infections), this approach failed, so the allograft was removed and a temporary cement spacer with antibiotic was implanted to control the infection. Forty-one patients subsequently had the spacer removed and were reconstructed after infection control with another bone allograft in 24 and an endoprostheses in 17. Four patients underwent an amputation for infection and four died of disease with the spacer in place. When we analyzed the 41 patients with a second reconstruction, 14 failed with a new infection (34%, 14 of 41 secondary reconstructed) of whom 12 had been reconstructed with bone allograft (29%) and two had endoprostheses (5%). CONCLUSIONS: Management of infections of massive bone allografts with antibiotics and surgical débridement usually resulted in failure. Infections could be treated with resection of the allograft, antibiotics, a temporary cement spacer with antibiotics, and a repeat reconstruction; however, this approach is unlikely to be successful if a second bone allograft is used. Infections are difficult to treat, and more studies are needed, but we propose that it might be preferable to use endoprosthesis reconstruction for salvage of an infected allograft. LEVEL OF EVIDENCE: Level III, therapeutic study.

Revision Distal Femoral Arthroplasty With the Compress(®) Prosthesis Has a Low Rate of Mechanical Failure at 10 Years.

BACKGROUND: Patients with failed distal femoral megaprostheses often have bone loss that limits reconstructive options and contributes to the high failure rate of revision surgery. The Compress(®) Compliant Pre-stress (CPS) implant can reconstruct the femur even when there is little remaining bone. It differs from traditional stemmed prostheses because it requires only 4 to 8 cm of residual bone for fixation. Given the poor long-term results of stemmed revision constructs, we sought to determine the failure rate and functional outcomes of the CPS implant in revision surgery. QUESTIONS/PURPOSES: (1) What is the cumulative incidence of mechanical and other types of implant failure when used to revise failed distal femoral arthroplasties placed after oncologic resection? (2) What complications are characteristic of this prosthesis? (3) What function do patients achieve after receiving this prosthesis? METHODS: We retrospectively reviewed 27 patients who experienced failure of a distal femoral prosthesis and were revised to a CPS implant from April 2000 to February 2013. Indications for use included a minimum 2.5 mm cortical thickness of the remaining proximal femur, no prior radiation, life expectancy > 10 years, and compliance with protected weightbearing for 3 months. The cumulative incidence of failure was calculated for both mechanical (loss of compression between the implant anchor plug and spindle) and other failure modes using a competing risk analysis. Failure was defined as removal of the CPS implant. Followup was a minimum of 2 years or until implant removal. Median followup for patients with successful revision arthroplasty was 90 months (range, 24-181 months). Functional outcomes were measured with the Musculoskeletal Tumor Society (MSTS) functional assessment score. RESULTS: The cumulative incidence of mechanical failure was 11% (95% confidence interval [CI], 4%-33%) at both 5 and 10 years. These failures occurred early at a median of 5 months. The cumulative incidence of other failures was 18% (95% CI, 7%-45%) at 5 and 10 years, all of which were deep infection. Three patients required secondary operations for cortical insufficiency proximal to the anchor plug in bone not spanned by the CPS implant and unrelated to the prosthesis. Median MSTS score was 27 (range, 24-30). CONCLUSIONS: Revision distal femoral replacement arthroplasty after a failed megaprosthesis is often difficult as a result of a lack of adequate bone. Reconstruction with the CPS implant has an 11% failure rate at 10 years. Our results are promising and demonstrate the durable fixation provided by the CPS implant. Further studies to compare the CPS prosthesis and other reconstruction options with respect to survival and functional outcomes are warranted. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Survival, recurrence, and function after epiphyseal preservation and allograft reconstruction in osteosarcoma of the knee.

BACKGROUND: Bone tumor resections for limb salvage have become the standard treatment. Recently, intercalary tumor resection with epiphyseal sparing has been used as an alternative in patients with osteosarcoma. The procedure maintains normal joint function and obviates some complications associated with osteoarticular allografts or endoprostheses; however, long-term studies analyzing oncologic outcomes are scarce, and to our knowledge, the concern that a higher local recurrence rate may be an issue has not been addressed. QUESTIONS/PURPOSES: We wanted to assess (1) the overall survival in patients treated with this surgical technique; (2) the percentage of local recurrence and limb survival, specifically the incidence of recurrence in the remaining epiphysis; (3) the frequency of orthopaedic complications, and, (4) the functional outcomes in patients who have undergone intercalary tumor resection. METHODS: We analyzed all 35 patients with osteosarcomas about the knee (distal femur and proximal tibia) treated at our center between 1991 and 2008 who had resection preserving the epiphysis and reconstruction with intercalary allografts. Minimum followup was 5 years, unless death occurred earlier (mean, 9 years; range, 1-16 years), and no patients were lost to followup. During the study period, our indications for this approach included patients without metastases, with clinical and imaging response to neoadjuvant chemotherapy, that a residual epiphysis of at least 1 cm thickness could be available after a surgical margin width in bone of 10 mm was planned, and 16% of patients (35 of 223) meeting these indications were treated using this approach. Using a chart review, we ascertained overall survival of patients, oncologic complications such as local recurrence and tumor progression, limb survival, and orthopaedic complications including infection, fracture, and nonunion. Survival rates were estimated using the Kaplan-Meier method. Patient function was evaluated using the Musculoskeletal Tumor Society (MSTS)-93 scoring system. RESULTS: Overall survival rate of the patients was 86% (95% CI, 73%-99%) at 5 and 10 years. Five patients died of disease. No patient had a local recurrence in the remaining bony epiphysis, but three patients (9%; 95% CI, 0%-19%) had local recurrence in the soft tissue. The limb survival rate was 97% (95% CI, 89%-100%) at 5 and 10 years. Complications treated with additional surgical procedures were recorded for 19 patients (54%), including three local recurrences, two infections, 11 fractures, and three nonunions. In 10 of these 19 patients, the allograft was removed. Only five of the total 35 study patients (14%) lost the originally preserved epiphysis owing to complications. The mean functional score was 26 points (range, 10-30 points, with a higher score representing a better result) at final followup. CONCLUSIONS: Although the recurrence rate was high in this series, the small sample size means that even one or two fewer recurrences might have resulted in a much more favorable percentage. Because of this, future, larger studies will need to determine whether this is a safe approach, and perhaps should compare epiphyseal preservation with other possible approaches, including endoprosthetic reconstruction and/or osteoarticular allografts. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Should fractures in massive intercalary bone allografts of the lower limb be treated with ORIF or with a new allograft?

BACKGROUND: Massive bone allografts have been used for limb salvage of bone tumor resections as an alternative to endoprostheses, although they have different outcomes and risks. There is no general consensus about when to use these alternatives, but when it is possible to save the native joints after the resection of a long bone tumor, intercalary allografts offer some advantages despite complications, such as fracture. The management and outcomes of this complication deserve more study. QUESTIONS/PURPOSES: The purposes of this study were to (1) analyze the fracture frequency in a group of patients treated with massive intercalary bone allografts of the femur and tibia; (2) compare the results of allografts treated with open reduction and internal fixation (ORIF) with those treated with resection and repeat allograft reconstruction; and (3) determine the likelihood that treatment of a fracture resulted in a healed intercalary reconstruction. METHODS: We reviewed patients treated with intercalary bone allografts between 1991 and 2011. During this period, patients were generally treated with intercalary allografts when after tumor resection at least 1 cm of residual epiphysis remained to allow fixation of the osteotomy junction. To obtain a homogeneous group of patients, we excluded allograft-prosthesis composites and osteoarticular and hemicylindrical intercalary allografts from this study. We analyzed the fracture rate of 135 patients reconstructed with segmental intercalary bone allografts of the lower extremities (98 femurs and 37 tibias). In patients whose grafts fractured were treated either by internal fixation or a second allograft, ORIF generally was attempted but after early failures in femur fractures, these fractures were treated with a second allograft. Using a chart review, we ascertained the frequency of osseous union, complications, and reoperations after the treatment of fractured intercalary allografts. Followup was at a mean of 101 months (range, 24-260 months); of the original 135 patients, no patient was lost to followup. RESULTS: At latest followup, 19 patients (14%) had an allograft fracture (16 femurs [16%] and three tibias [8%]). Six patients were treated with internal fixation and addition of autologous graft (three femurs and three tibias) and 13 patients were treated with a second intercalary allograft (13 femurs). The three patients with femoral allograft fractures treated with internal fixation and autologous grafts failed and were treated with a second allograft, whereas those patients with tibia allograft fractures treated by the same procedure healed without secondary complications. When we analyzed the 16 patients with a second intercalary allograft (13 as primary treatment of the fracture and three as secondary treatment of the fracture), five failed (31%) and were treated with resection of the allograft and reconstructed with an endoprosthesis (four patients) or an osteoarticular allograft (one patient). CONCLUSIONS: Fractures of intercalary allografts of the tibia could successfully be treated with internal fixation and autologous iliac crest bone graft; however, this treatment failed when used for femur allograft fractures. Femoral fractures could be treated with resection and repeat allograft reconstruction, however, with a higher refracture frequency. The addition of a vascularized fibular graft in the second attempt should be considered. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

A High-grade Sarcoma Arising in a Patient With Recurrent Benign Giant Cell Tumor of the Proximal Tibia While Receiving Treatment With Denosumab.

BACKGROUND: A giant cell tumor of bone is a primary benign but locally aggressive neoplasm. Malignant transformation in a histologically typical giant cell tumor of bone, without radiotherapy exposure, is an uncommon event, occurring in less than 1% of giant cell tumors of bone. Although surgery is the standard initial treatment, denosumab, a monoclonal antibody drug that inhibits receptor activator of nuclear factor-κB ligand (RANKL), has shown considerable activity regarding disease and control of symptoms in patients with recurrence, unresectable, and metastatic giant cell tumors of bone. CASE DESCRIPTION: We report the case of a 20-year-old woman with a recurrent benign, giant cell tumor of bone, who had a bone sarcoma develop while receiving denosumab treatment. LITERATURE REVIEW: To our knowledge, there have been no reports of infection or malignancy with low-dose denosumab administration for osteoporosis. However, while there are relatively few reported side effects, the safety of denosumab and adverse events seen with higher doses, as used in treatment of giant cell tumors of bone are not well defined. CLINICAL RELEVANCE: Denosumab has become a valuable adjunct for treatment of recurrent or unresectable giant cell tumor of bone. It is not clear if our patient's malignant transformation of a giant cell tumor of bone while receiving denosumab treatment was caused by denosumab, but it is important to be aware of the possibility if more cases occur. Future studies should focus on the safety of high-dose denosumab administration in patients with a benign unresectable giant cell tumor of bone.

Does intraoperative navigation assistance improve bone tumor resection and allograft reconstruction results?

BACKGROUND: Bone tumor resections for limb salvage have become standard treatment. Recently, computer-assisted navigation has been introduced to improve the accuracy of joint arthroplasty and possible tumor resection surgery; however, like with any new technology, its benefits and limitations need to be characterized for surgeons to make informed decisions about whether to use it. QUESTIONS/PURPOSES: We wanted to (1) assess the technical problems associated with computer-assisted navigation; (2) assess the accuracy of the registration technique; (3) define the time required to perform a navigated resection in orthopedic oncology; and (4) the frequency of complications such as local recurrence, infection, nonunion, fracture, and articular collapse after tumor resection and bone reconstruction with allografts using intraoperative navigation assistance. METHODS: We analyzed 69 consecutive patients with bone tumors of the extremities that were reconstructed with massive bone allografts using intraoperative navigation assistance with a minimum followup of 12 months (mean, 29 months; range, 12-43 months). All patients had their tumors reconstructed in three-dimensional format in a virtual platform and planning was performed to determine the osteotomy position according to oncology margins in a CT-MRI image fusion. Tumor resections and allograft reconstructions were performed using a computer navigation system according to the previously planned cuts. We analyzed intraoperative data such as technical problems related to the navigation procedure, registration technique error, length of time for the navigation procedure, and postoperative complications such as local recurrence, infection, nonunion, fracture, and articular collapse. RESULTS: In three patients (4%), the navigation was not carried out as a result of technical problems. Of the 66 cases in which navigation was performed, the mean registration error was 0.65 mm (range, 0.3-1.2 mm). The mean required time for navigation procedures, including bone resection and allograft reconstruction during surgery, was 35 minutes (range, 18-65 minutes). Complications that required a second surgical procedure were recorded for nine patients including one local recurrence, one infection, two fractures, one articular collapse, and four nonunions. In two of these nine patients, the allograft needed to be removed. At latest followup, three patients died of their original disease. CONCLUSIONS: The navigation procedure could not be performed for technical reasons in 4% of the series. The mean registration error was 0.65 mm in this series and the navigation procedure itself adds a mean of 35 minutes during surgery. The complications rate for this series was 14%. We found a nonunion rate of 6% in allograft reconstructions when we used a navigation system for the cuts. LEVEL OF EVIDENCE: Level IV, case series. See the Guidelines for Authors for a complete description of levels of evidence.

[Low grade parosteal osteosarcoma. Clinical and oncological outcomes]. / Osteosarcoma parostal de bajo grado. Evolución oncológica y clínica.

The objective of the study was to analyze a group of patients with low grade parosteal osteosarcoma treated with limb salvage surgery and reconstructed with bone allograft. A retrospective review from our oncologic data base between 1980 and 2010 was done and all patients with diagnosis of low grade parosteal osteosarcoma, treated with limb salvage surgery and reconstructed with allograft were included. Twenty-two patients were included for the analysis. The mean age was 32±11 years (10-59) y the mean follow-up 93±69 months (8-237). Ten year overall survival of the series was 91% (95% CI: 79-100). Four patients developed local recurrence, 2 of them histological classified after the resection dedifferentiated parosteal osteosarcoma. Two patients developed distant recurrence, being the lung the only site of metastasis. Ten year limb salvage reconstruction survival was 65% (95% CI: 44-86). Long term survival rate in low grade parosteal osteosarcoma is over 90%. Surgical resection wide margin should be the elective treatment and biological limb salvage reconstruction is a good alternative.

[Osteosarcoma lung metastases. Survival after chemotherapy and surgery]. / Metástasis pulmonares en osteosarcoma. Neoadyuvancia, tratamiento quirúrgico y supervivencia.

Five years overall survival in osteosarcoma patients is around 70%, although in patients with metastatic disease it is only 10-30%. The objective of this study was to analyze overall survival and prognostic factors in a group of patients with metastatic osteosarcoma treated with surgical removal of the lung metastases. A retrospective review from our oncology data base revealed 38 patients treated between 1992 and 2006. The mean age at diagnosis was 18 ± 9.4 years (3-45) and mean follow-up was 57 ± 53.8 months (12-231). All patients were treated with chemotherapy and oncologic resection of the primary tumor and surgical removal of the lung metastases. We analyzed overall survival and prognostic factors: age, gender, site, time of metastasis, local recurrences, number of lung metastasis and chemotherapy response (necrosis). Overall survival of the entire series was 29% at 5 years (CI 95%: 14.5-43.5) and 26% at 10 years (CI 95%: 12-40). Significant difference in 5 year overall survival was found between good and bad responders to chemotherapy, 53% (IC 95%: 28-78) vs. 8% (IC 95%: 0-20) (p = 0.0008). No statistically significant relationship between other prognostic factors analyzed was observed. Five and ten years overall survival rates in osteosarcoma patients with lung metastasis treated with chemotherapy and surgically resection is poor. Patients with good response to chemotherapy have better prognosis.

[Oncological outcomes and prognostic factors in surgically treated patients with synovial sarcoma]. / Resultados oncológicos y factores pronósticos en pacientes con sarcoma sinovial tratados quirúrgicamente.

INTRODUCTION: Synovial sarcoma is an unusual tumor with an incidence of 1-3 cases per million. It is more frequent in teenagers and young adults under 30. It develops anywhere, but the extremities are the most frequent place of appearance (80% extremities, 20% other locations: 8% trunk, 7% retroperitoneal/abdominal, 5% head and neck). Oncological results are different depending on the study. Survival rate free of local recurrence, survival rate free of events and global survival rate vary upon published studies. The same happens with the disease's prognostic factors. METHODS: The objective was to analyze a group of 43 patients with diagnosis of synovial sarcoma of the extremities treated surgically and determine (1) global survival rate, (2) survival rate free of events, (3) local recurrence rate and (4) oncological risk factors. RESULTS: The global survival rate at 2 years was 90% (IC95%: 76 - 96%) and 67% (IC95%: 49-80%) at 5 years. The survival rate free of events at 2 years was 68% (IC95% 51-80%) and 48% (IC95% 32-52%) at 5 years. The recurrence rate at 2 years was 9% (IC95% 3-25%) and 25% (IC95% 13-46%) at 5 years. The histological grade and metastatic presence were bad prognostic factors. DISCUSSION: We can conclude that our oncological results are in line with those published in previous series and that there were two factors associated with poor prognosis.

Introducción: El sarcoma sinovial es un tumor raro (incidencia de 1-3 casos por millón). Es más frecuente en adolescentes y adultos menores de 30 años. Se desarrolla en cualquier parte del cuerpo, siendo, las extremidades el lugar más frecuente de aparición (80% extremidades y 20% otras localizaciones: 8% tronco, retroperitoneal/ abdominal 7%, cabeza y cuello 5%). Los resultados oncológicos de los pacientes con sarcoma sinovial son disímiles. La tasa de supervivencia libre de recurrencia local, la supervivencia libre de eventos y la supervivencia global varían entre las series publicadas. Lo mismo sucede con los factores pronósticos de la enfermedad. Métodos: El objetivo fue analizar un grupo de 43 pacientes con diagnóstico de sarcoma sinovial de las extremidades tratados quirúrgicamente, y determinar (1) tasa de supervivencia global, (2) tasa de supervivencia libre de eventos, (3) tasa de recurrencia local y (4) factores de riesgo oncológicos. Resultados: La supervivencia global a los 2 años fue 90% (IC95%: 76-96%), y 67% (IC95%: 49-80%) a los 5 años. La supervivencia libre de eventos a los 2 años fue 68% (IC95% 51-80%) y a los 5 años 48% (IC95% 32-52%). El riesgo de recurrencia local a 2 años fue 9% (IC95% 3-25%) y a los 5 años 25% (IC95% 13-46%). Los factores de mal pronóstico oncológico fueron el grado histológico y la presencia de metástasis. Discusión: Podemos concluir que nuestros resultados oncológicos se asemejan a las series publicadas y que en nuestra serie hubo dos factores de mal pronóstico.

Intercalary femur allografts are an acceptable alternative after tumor resection.

BACKGROUND: With the improved survival for patients with malignant bone tumors, there is a trend to reconstruct defects using biologic techniques. While the use of an intercalary allograft is an option, the procedures are technically demanding and it is unclear whether the complication rates and survival are similar to other approaches. QUESTIONS/PURPOSES: We evaluated survivorship, complications, and functional scores of patients after receiving intercalary femur segmental allografts. PATIENTS AND METHODS: We retrospectively reviewed 83 patients who underwent an intercalary femur segmental allograft reconstruction. We determined allograft survival using the Kaplan-Meier method. We evaluated patient function with the Musculoskeletal Tumor Society scoring system. Minimum followup was 24 months (median, 61 months; range, 24-182 months). RESULTS: Survivorship was 85% (95% confidence interval: 93%-77%) at 5 years and 76% (95% confidence interval: 89%-63%) at 10 years. Allografts were removed in 15 of the 83 patients: one with infection, one with local recurrence, and 13 with fractures. Of the 166 host-donor junctions, 22 (13%) did not initially heal. Nonunion rate was 19% for diaphyseal junctions and 3% for metaphyseal junctions. We observed an increase in the diaphysis nonunion rate in patients fixed with nails (28%) compared to those fixed with plates (15%). Fracture rate was 17% and related to areas of the allograft not adequately protected with internal fixation. All patients without complications had mainly good or excellent Musculoskeletal Tumor Society functional results. CONCLUSIONS: Diaphyseal junctions have higher nonunion rates than metaphyseal junctions. The internal fixation should span the entire allograft to avoid the risk of fracture. Our observations suggest segmental allograft of the femur provides an acceptable alternative in reconstructing tumor resections. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.