German L. Farfalli

Accuracy of 3-D planning and navigation in bone tumor resection.

Surgical precision in oncologic surgery is essential to achieve adequate margins in bone tumor resections. Three-dimensional preoperative planning and bone tumor resection by navigation have been introduced to orthopedic oncology in recent years. However, the accuracy of preoperative planning and navigation is unclear. The purpose of this study was to evaluate the accuracy of preoperative planning and the navigation system. A total of 28 patients were evaluated between May 2010 and February 2011. Tumor locations were the femur (n=17), pelvis (n=6), sacrum (n=2), tibia (n=2), and humerus (n=1). All resections were planned in a virtual scenario using computed tomography and magnetic resonance imaging fusion. A total of 61 planes or osteotomies were performed to resect the tumors. Postoperatively, computed tomography scans were obtained for all surgical specimens, and the specimens were 3-dimensionally reconstructed from the scans. Differences were determined by finding the distances between the osteotomies virtually programmed and those performed. The global mean of the quantitative comparisons between the osteotomies programmed and those obtained through the resected specimen was 2.52±2.32 mm for all patients. Differences between osteotomies virtually programmed and those achieved by navigation intraoperatively were minimal.

Does increased rate of limb-sparing surgery affect survival in osteosarcoma?

BackgroundThe emergence of limb salvage surgery as an option for patients with osteosarcoma is attributable to preoperative chemotherapy and advancements in musculoskeletal imaging and surgical technique. While the indications for limb salvage have greatly expanded it is unclear whether limb salvage affects overall survival.Questions/purposesWe asked whether over the past three decades limb-sparing procedures in high-grade osteosarcoma had increased, and whether this affected survival and ultimate amputation.MethodsWe retrospectively reviewed 251 patients with high-grade osteosarcoma treated from 1980 to 2004 with a multidisciplinary approach, including neoadjuvant chemotherapy. We compared survival rates, limb-salvage treatment, and amputation after limb-sparing procedure during three different periods of time. Fifty-three patients were treated from 1980 to 1989, 97 from 1990 to 1999, and 101 from 2000 to 2004. Thirty-seven patients were treated with primary amputations and 214 with primary limb salvage.ResultsThe 5-year survival rate in the first period was 36%, whereas in the 1990s, it was 60% and 67% from 2000–2004. Limb salvage surgery rate in the 1980s was 53% (28 of 53), whereas in the 1990s, it was 91% (88 of 97) and 97% from 2000–2004 (98 of 101). In the limb salvage group, 22 of the 214 patients (10%) required secondary amputation; the final limb salvage rate in the first period was 36% (19 of 53), whereas in the 1990s, it was 81% (79 of 97) and 93% from 2000–2004 (94 of 101).ConclusionsPatients with osteosarcoma treated in the last two periods had higher rates of limb salvage treatment and survival, with lower secondary amputation.Level of EvidenceLevel III, prognostic 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

BackgroundA 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 DescriptionWe 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 ReviewTo 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 RelevanceDenosumab 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.

Complications in Total Knee Arthroplasty After High Tibial Osteotomy

The outcome of total knee arthroplasty (TKA) after high tibial osteotomy remains uncertain. Compared with primary TKA, the results in some studies are not significantly different. Others report adverse effects on the outcome. The purpose of this study was to determine (1) the middle- and long-term survival of TKA performed after high tibial osteotomy, (2) their clinical and radiographic results, and (3) what complications could be expected in this group of patients.The study group comprised 31 patients (34 knees) undergoing cemented TKA after high tibial osteotomy. Average follow-up was 8 years (range, 6-213 months). Survival of the TKA was estimated using the Kaplan-Meier method. Outcomes were documented using the Hospital for the Special Surgery score. The results showed that the Kaplan-Meier survival rate was 82% at 5 years and 76% at 10 years. Excellent and good clinical results were obtained in 67% of patients. Complications occurred in 12 (35%) knees: stiffness in 4, aseptic loosening in 2, patellofemoral subluxation in 1, instability in 1, inexplicable pain in 1, and deep infection in 3.Great care with technical details is necessary when high tibial osteotomy is indicated because a future conversion to TKA may occur.

Effect of erroneous surgical procedures on recurrence and survival rates for patients with osteosarcoma.

To determine whether inappropriate surgical procedures based on an initial misdiagnosis affected recurrence and survival rates, we retrospectively reviewed the surgical treatment and results of 117 patients with high-grade osteosarcomas treated from January 1, 1990 to December 31, 2000. Nine patients had intralesional curettage performed at other institutions based on an erroneous diagnosis of a benign lesion. Two of the nine patients had amputations and seven patients had limb-salvage procedures. Of the 108 patients who were not misdiagnosed, six patients had amputations and 102 patients had limb-salvage procedures. All patients received neoadjuvant therapy. Fifteen of the 117 patients had local recurrences. Patients who had erroneous surgical procedures based on the initial misdiagnosis of osteosarcoma had an increased risk of local recurrence and decreased 10- year survival rate. Response to adjuvant therapy and the amount of previous violation of natural tumor barriers should be evaluated carefully before deciding surgical treatment. Level of Evidence: Level III, therapeutic study (Retrospective comparative study). See the Guidelines for Authors for a complete description of levels of evidence.

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

BackgroundMassive 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/purposesThe 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.MethodsWe 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.ResultsDuring 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%).ConclusionsManagement 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 EvidenceLevel III, therapeutic study.

Unicondylar Osteoarticular Allografts of the Knee

BACKGROUND In the management of a resected distal femoral or proximal tibial condyle as the result of tumor or trauma, a unicondylar osteoarticular allograft is currently the only reconstructive option that avoids the sacrifice of the unaffected condyle. The purposes of this study were to perform a survival analysis of unicondylar osteoarticular allografts of the knee and to evaluate the complications. METHODS We retrospectively reviewed the results of forty large unicondylar osteoarticular allograft procedures in thirty-eight patients who were followed for a mean of eleven years. Twenty-nine allografts were femoral transplants and included eleven medial and eighteen lateral femoral condyles. Eleven allografts were tibial transplants, including four medial and seven lateral tibial condyles. The procedure was performed after a tumor resection in thirty-six patients and to replace condylar loss after a severe open fracture in the remaining two patients. Complications were analyzed, and allograft survival from the date of implantation to the date of revision or the time of the latest follow-up was determined. Functional and radiographic results were documented according to the Musculoskeletal Tumor Society scoring system at the time of the latest follow-up. RESULTS One patient died of tumor-related causes without allograft failure before the two-year follow-up evaluation. The global rate of allograft survival at both five and ten years was 85%, with a mean follow-up of 148 months. In six patients, the allografts were removed at an average of twenty-six months (range, six to forty-eight months) and these were considered failures. All six patients underwent a second allograft procedure including two new unicondylar and four bicondylar reconstructions. The mean radiographic score for the thirty-three surviving allografts evaluated was 89%, with an average functional score of 27 of a possible 30 points. CONCLUSIONS Unicondylar osteoarticular allografts of the knee appear to be a reliable alternative for patients in whom reconstruction of massive osteoarticular bone loss is limited to one condyle of the femur or tibia.

Multiplanar osteotomies guided by navigation in chondrosarcoma of the knee.

Surgical resection with adequate margins is the treatment of choice in chondrosarcoma. However, well-circumscribed lesions can be completely resected by performing multi-planar osteotomies guided by computer-assisted navigation. This type of resection had been recently described in select patients with sarcomas; however, these osteotomies are technically demanding to plan and perform intraoperatively. The use of navigation to assist in surgery is becoming more frequently described in orthopedic oncology.The authors performed multiplanar osteotomy resections guided by navigation and reconstruction with intercalary allografts in 5 patients with chondrosarcoma around the knee. All the patients were women, with a mean age of 56 years. Four tumors were located in the distal femur and 1 in the proximal tibia. The 5 surgical anatomic specimens were 3-dimensionally reconstructed postoperatively and superimposed on a preoperative plan to check whether the resected specimen was consistent with the preoperative planned resection. At final follow-up, no patient experienced a local recurrence or metastasis. Four osteotomies each were performed in 3 patients, and 3 osteotomies each were performed in 2 patients, so 18 planes were evaluated. Mean difference in distance between preoperative vs final planes was 2.43 mm. Average functional score was 29 points. All patients resumed activities of daily living without restriction. This studys results show that navigation with adequate preoperative planning allows surgeons to intraoperatively reproduce the planned resection with accuracy in complex multiplanary resections.

Clinical and functional outcomes of tibial intercalary allografts after tumor resection.

Reconstruction after intercalary resection of the tibia is demanding due to subcutaneous location, poor vascularity of the tibia, and high infection rate. The purpose of this study was to evaluate the survivorship, complications, and functional outcome of intercalary tibial allograft reconstructions following tumor resections. Intercalary tibia segmental allografts were implanted in 26 consecutive patients after segmental resections. Patients were followed for an average of 6 years. Allograft survival was determined with the Kaplan-Meier method. Patient function was evaluated with the Musculoskeletal Tumor Society (MSTS) scoring system. Survivorship was 84% (95% confidence interval [CI], 98%-70%) at 5 years and 79% (95% CI, 63%-95%) at 10 years. Allografts were removed in 5 patients due to 3 infections and 2 local recurrences. Two patients showed diaphyseal nonunion, and 3 patients underwent an incomplete fracture; no allografts were removed in these patients. Average MSTS functional score was 29 points (range, 27-30 points). Despite the incidence of complications, this analysis showed an acceptable survivor-ship with excellent functional scores. The use of intercalary allograft has a place in the reconstruction of a segmental defect created by the resection of a tumor in the diaphyseal or metaphyseal portion of the tibia.

The Principles and Applications of Fresh Frozen Allografts to Bone and Joint Reconstruction

Fresh frozen allograft reconstruction has been used for a long time in massive bone loss in orthopedic surgery. Allografts have the advantage of being biologic reconstructions, which gives them durability. Despite a greater number of complications in the short term, after 5 years these stabilize with high rates of survival after 10 years. The rate of early complications and the need for careful management in the first years has led the orthopedic surgeon to the use of other options. However, the potential durability of this reconstruction makes this one of the best options for younger patients with high life expectancy.