Prosthetic knee replacement after resection of a malignant tumor of the distal part of the femur. Medium to long-term results

The anterior popliteal approach for popliteal exploration, distal femoral resection, and endoprosthetic reconstruction

Distal femoral resection and endoprosthetic reconstruction are sometimes associated with flap necrosis and inadequate soft tissue coverage. We evaluated the anterior popliteal surgical approach, which was designed to reduce those complications by using a posteromedial myocutaneous flap based upon the vastus medialis. A retrospective analysis of 46 consecutive patients was performed, and results were compared with historical controls. Compared with 19.4% with wound complications and 22.7% with gastrocnemius flap transfers in previous series by the senior author, 7.8% of patients in the present study had minimal superficial flap necrosis, and no gastrocnemius transfers for soft tissue coverage were required. The median Musculoskeletal Tumor Society score was 26, and the local recurrence rate 2 years or more after resection of osteosarcoma was 4%. The anterior popliteal approach to the distal femur limited wound complications and provided good soft tissue coverage of the endoprostheses.

Orthopedic Surgery Options for the Treatment of Primary Osteosarcoma

Background

Osteosarcoma is the most common malignant primary neoplasm of bone. Orthopedic procedures are essential components in the multidisciplinary treatment of osteosarcoma. Limb-salvaging procedures offer adequate disease control comparable to the results obtained by amputations. This review discusses the advantages and disadvantages of the various types of amputations and the limb-salvaging techniques for the treatment of osteosarcoma.

Methods

The authors analyzed the characteristics of limb-salvaging procedures and amputations for osteosarcoma. Qualitative and quantitative studies published in the English language that are listed in the National Library of Medicine were used as the basis for this review. In addition, a review of an expandable prosthesis is included.

Results

Limb-salvaging techniques have acceptable rates of disease control. However, amputation remains a valid procedure in selected cases of osteosarcoma in most parts of the world. Orthopedic oncology surgeons have various materials, procedures, and techniques available to achieve disease control and improve function in patients with osteosarcoma.

Conclusions

The surgical management of patients with osteosarcoma is challenging. No difference in survival has been shown between amputations and adequately performed limb-salvaging procedures. Optimal tumor resection and a functional residual limb with increased patient survival are the goals of modern orthopedic oncology.

The use of pasteurized autologous grafts for periacetabular reconstruction

Reconstruction after periacetabular resection is a challenge. We asked whether the use of pasteurized autologous grafts would provide satisfactory results regarding patient survival, local recurrence, and metastasis, and graft union and functional outcome. We retrospectively reviewed 11 patients having such grafts with a minimum followup of 12 months (mean, 40 months; range, 12-116 months). All patients underwent periacetabular (Type II) resection of malignant periacetabular tumors. The resected bone was treated in saline at 65 degrees C for 30 minutes and reimplanted into the host bone with internal fixation. Total hip arthroplasty was performed in all patients. Local recurrence occurred in two of nine patients with primary sarcoma. Ten grafts survived at the last followup. Union of the resected bone with the host bone was achieved in eight of the 11 patients at an average of 12 months. The overall functional rating was 61% according to the Musculoskeletal Tumor Society System, with better results in the patients with primary tumors. Graft fracture (one patient) and infection (one patient) were the major complications. Our data suggest the use of pasteurization may be a reasonable option for reconstruction after resection of malignant periacetabular tumors.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Endoprosthetic replacement of the distal femur for bone tumours: long-term results

We investigated whether improvements in design have altered the outcome for patients undergoing endoprosthetic replacement of the distal femur after resection of a tumour. Survival of the implant and 'servicing' procedures have been documented using a prospective database, review of the design of the implant and case records. In total, 335 patients underwent a distal femoral replacement, 162 having a fixed-hinge design and 173 a rotating-hinge. The median age of the patients was 24 years (interquartile range 17 to 48). A total of 192 patients remained alive with a mean follow-up of 12 years (5 to 30). The risk of revision for any reason was 17% at five years, 33% at ten years and 58% at 20 years. Aseptic loosening was the main reason for revision of the fixed-hinge knees while infection and fracture of the stem were the most common for the rotating-hinge implant. The risk of revision for aseptic loosening was 35% at ten years with the fixed-hinge knee, which has, however, been replaced by the rotating-hinge knee with a hydroxyapatite collar. The overall risk of revision for any reason fell by 52% when the rotating-hinge implant was used. Improvements in the design of distal femoral endoprostheses have significantly decreased the need for revision operations, but infection remains a serious problem. We believe that a cemented, rotating-hinge prosthesis with a hydroxyapatite collar offers the best chance of long-term survival of the prosthesis.

Functional outcome after endoprosthetic limb-salvage therapy of primary bone tumours--a comparative analysis using the MSTS score, the TESS and the RNL index

Limb-saving therapy for primary bone tumours is the treatment of choice. We aimed at analysing the quality of life of this group of patients by combining three different tools. Eighty-seven patients (46 females, 41 males) with a primary bone tumour of the extremity who had undergone endoprosthetic reconstruction between 1982 and 2000 were included in this retrospective study. The median age at the time of evaluation was 30 (12-73) years. The Toronto Extremity Salvage Score (TESS) and the Reintegration to Normal Living index (RNL) were recorded an average of 5.8 years after reconstruction and the Musculoskeletal Tumour Society Score (MSTS) after an average of 6.5 years. The mean MSTS score was 77% (13-93%). The mean TESS was 82% (22-99%), and the mean RNL index was 87% (32-98%). The subjective satisfaction and acceptance of physical impairment were significantly higher than the objective score (p < 0.001). The TESS was 88% in patients aged 12-25 years, 81% in those aged 26-40 years and 57% in those aged 41-73 years. Parallel recording of the MSTS score, TESS and RNL index provides a better measure reflecting the complex situation of the patients by combining objective and subjective parameters.

Salvaging the limb salvage: management of complications following endoprosthetic reconstruction for tumours around the knee

INTRODUCTION

Limb-salvage surgery, including endoprosthetic reconstruction after tumour resection, has become the standard management for local control of tumours around the knee. As the nature of surgery is technically complex and demanding, there is potential for significant morbidity arising from complications. This study describes our experience with complications following endoprosthetic reconstruction around the knee.

METHODS

Retrospective analysis of consecutive resections and endoprosthetic reconstructions for tumours around the knee between 1996 and September 2005 performed at St Vincent's Hospital, Melbourne.

RESULTS

Fifty consecutive cases were reviewed, with a median follow-up of 24.5 (range, 2-124) months. Median age was 41 (range, 13-79) years. Tumour types included 38 primary musculoskeletal malignancies, 8 metastatic tumours, 2 bony lymphomas and 2 benign lesions. There were eight deaths, nine cases of subsequent metastatic spread and no local recurrences. There were six cases of deep infection, two each of non-resolving nerve palsy, fracture and mechanical wear, and one each of symptomatic patellofemoral impingement, aseptic loosening and intraoperative popliteal artery trauma. Five patients required endoprosthetic revision, and three subsequent amputations were described. Excellent functional outcome and emotional acceptance was observed amongst patients that underwent revision.

CONCLUSION

Resection and endoprosthetic reconstruction of tumours around the knee is both technically challenging and resource-intensive. It is imperative that morbidity from complications is limited through the minimisation of their incidence and the provision of optimal management. This series demonstrates that good patient outcomes can be achieved in specialist centres with experienced surgeons and adoption of a multidisciplinary approach.

Cementless fixation of megaprostheses using a conical fluted stem in the treatment of bone tumours

We reviewed 25 patients in whom a MUTARS megaprosthesis with a conical fluted stem had been implanted. There were three types of stem: a standard stem was used in 17 cases (three in the proximal femur, nine in the distal femur and five proximal tibia), a custom-made proximal femoral stem in four cases and a custom-made distal femoral stem in four cases. The mean age of the patients was 40.1 years (17 to 70) and the mean follow-up was for 2.5 years (0.9 to 7.4).

At follow-up two patients had died from their disease: one was alive with disease and 22 were disease-free. One of 23 prostheses had been removed for infection and another revised to a cemented stem. The mean Musculoskeletal Tumor Society score was 24.9 (12 to 30) and the mean Karnofsky index was 82% (60% to 100%).

There was no radiological evidence of loosening or subsidence. Stem stress shielding was seen in 11 patients and was marked in five of these.

There were five complications, rupture of the extensor mechanism of the knee after extra-articular resection in two patients, deep venous thrombosis in one, septic loosening in one, and dislocation of the hip in one.

The survival rate after seven years was 87% (95% confidence interval (CI) 83 to 91) for the patients and 95% (95% CI 91 to 99) for the megaprosthesis. A longer follow-up is needed to confirm these encouraging results.

Effect of chemotherapy on initial compressive osseointegration of tumor endoprostheses

Chemotherapy has long been suspected of having an adverse effect on bone healing. Massive tumor endoprostheses which achieve osseointegration via compressive force provide a unique model to study the effects of chemotherapy on bone healing. We compared distal femoral bone hypertrophy in patients who received chemotherapy with those who did not. Fifty four patients underwent distal femoral reconstruction with a compression implant. Thirty patients received chemotherapy (Group 1), and 24 did not (Group 2). The group of patients receiving chemotherapy was younger, had lower body mass indices, and had different diagnoses compared to the group of patients not receiving chemotherapy. We used a standardized technique to measure bone growth at the bone-prosthetic interface. The rate of cortical width increase at the bone-prosthetic junction was faster in Group 2 compared to Group 1. Similarly, the increase in cortical width from immediate postop to 3 months and 6 months postop was greater in Group 2 when compared to Group 1. The data suggest chemotherapy administration for musculoskeletal malignancy has a substantial initial adverse effect on bone hypertrophy and a trend towards reduced prosthetic survival. These findings have important implications for the patients with musculoskeletal tumors.

[Bilateral fibula graft. Biological reconstruction following resection of malignant bone tumors]

Bilateral vascularized fibula graft (BVFG) is actually not a satisfying method for the replacement of metadiaphyseal defects of the femur and tibia in young patients suffering from malignant bone tumors. This reconstruction was used in five patients (two female, three male, average age 15.2 years, femur n=3, tibia n=2) undergoing metadiaphyseal resection of malignant bone tumors between November 2000 and August 2003. The median length of the defect to be bridged was 16.4 cm (range 11.5-23). In the two cases of tibia reconstruction, the ipsilateral fibula was transposed into the osseous defect (fibula pro tibia). The vessels of the contralateral fibula graft were microscopically anastomosed end-to-side upon the a. and v. tibialis anterior. For the reconstruction of femoral defects, two free fibula grafts were used. All patients had multimodal treatment according to the EURO-E.W.I.N.G 99 or COSS-96 protocol. Median follow-up was at 34 months. In all cases, R0 status was achieved. None of the patients experienced local recurrence during follow-up. Radiographic signs of osseous remodeling were detected the earliest after 2 months. Full weight-bearing on the affected leg was permitted after 8-18 months. Complications occurred in four patients (bleeding 1, infection and pseudarthrosis 1, fracture 1, plate fracture 1). None of the complications led to failure of the reconstruction or to amputation. The MSTS scores was very good in two patients, good in two, and intermediate in one. Biological reconstruction of osseous defects is always desirable when possible. Good functional and durable results can be obtained using BVFG for the reconstruction of metadiaphyseal defects of the femur and tibia.

[The modular MML revision system in knee revision and tumor arthroplasty]

Increasing age and a higher level of mobility lead to an increasing incidence in revision arthroplasty after total knee replacement and tumor surgery. So far, the reconstruction of large defects in bony and soft tissue environments can be accomplished by the modern modular components of revision implants. The consecutive reconstruction of the extensor mechanism in extended revision has its own drawbacks and is often associated with significant functional limitations for the patient. Specially designed implants and methods are required to generate good functional results. The modular knee revision system MML provides specific modifications of the tibial component for reconstruction of the extensor mechanism. Combined with artificial strips, an excellent functional outcome could be achieved. In this study, 70 patients were operated with the MML endoprosthesis in knee revision or tumor surgery. An excellent functional outcome could be determined. At 7 years after surgery, an average of 32+/-13 points was achieved on the Oxford Knee Score. The outcome measurement using the functional scoring system of the American Knee Society (AKS score) showed similarly good results with 71+/-25 points out of 100. A minor deficit of only 2 degrees in active extension could be observed after reconstruction of the extensor mechanism. In conclusion, we have demonstrated that the MML modular revision system is appropriate for reconstruction of segmental bone defects.

Intra-arterial chemotherapy for limb preservation in patients with osteosarcoma: nursing implications

Osteosarcoma is an aggressive tumor found in children and young adults, originating primarily in the legs or arms. The high-grade tumor grows in a circular, ball-like mass in the bone tissue. Before the 1970s and the advent of chemotherapy use in osteosarcoma, treatment consisted solely of amputation. More recently, a preoperative regimen of intra-arterial (IA) cisplatin and infusional doxorubicin with limb-sparing procedures has provided an effective treatment option and improved survival for many patients with osteosarcoma. IA chemotherapy is administered through a small, temporary, external catheter that rests in the arterial vessel that supplies the tumor. The primary advantage of IA chemotherapy administration is the delivery of a higher chemotherapy concentration directly to the tumor site, Nursing management of patients with IA chemotherapy requires knowledge of treatment side effects and procedure-related assessments. Further implications for practice include instructing patients and families before and after the insertion of the IA line and giving discharge and long-term follow-up education. Oncology nurses are well positioned to assist children and young adult patients through difficulties with adjustment after treatment is completed and a response has been achieved, owing to advanced communication skills and knowledge of developmental stages and survivorship issues,

Early distal femoral endoprosthetic survival: cemented stems versus the Compress implant

Aseptic loosening is well known following endoprosthetic replacement (EPR) using cemented intramedullary stems (CISs). The Compress (CPS) implant uses a novel spring system, achieving immediate, high compression fixation that induces bone hypertrophy and avoids stress shielding. We compared 26 oncologic distal femoral CPS patients treated at the University of California, San Francisco (UCSF, USA) with 26 matched CIS patients from the Royal Orthopaedic Hospital, Birmingham (ROH, UK). The predominant diagnosis was osteosarcoma. Each centre had only one device-related prosthetic failure. In the short term these results show CPS to be safe and effective. We await longer follow-up to assess the ongoing potential for prosthetic failure.

Megaprostheses for the treatment of malignant bone tumours of the lower limbs

Lower limb salvage surgery remains a challenge in orthopaedic oncology. Both cemented and cementless, modular, endoprosthetic systems are widely used to treat defects of different sizes. The systems have changed over the years, and each major orthopaedic company offers a modular tumour and revision system for the lower extremities. All systems have worse long-term results compared to conventional total hip or total knee systems. This is due to the large defects that need to be bridged with a more difficult fixation in the diapyhsis of the femur and tibia and a more complex restoration of joint biomechanics. This article summarises the results of several clinical studies with different systems. Newer systems without clinical follow-up are described. We previously reported a prospective study of 50 consecutive patients treated with the MUTARS endoprostheses. The follow-up was 2-7 years. Clinical evaluation showed good results compared to other systems. The review of the literature and our own results do not validate the support or favouring of one specific system. The surgeon should choose a system with which he/she is familiar and that provides the modularity needed intraoperatively to bridge any defect in the lower limbs.

Survival of tumor megaprostheses replacements about the knee

Limb salvage surgery is an effective procedure with a low risk of tumor recurrence. In an attempt to define the incidence of implant failure at 2, 5, and 10 years postoperatively, we retrospectively reviewed implant survival in a group (n = 105) of pediatric (< 18 years of age) and adult patients who were treated with distal femoral and/or proximal tibial implants for extremity tumors. Issues regarding the timing of failure, reason for failure, and whether pediatric patients had higher rates of failure were posed as secondary questions. The median followup was 57 months (1-235 months). Thirty-two (32/105, 31%) patients had 42 implant failures. The mean prosthesis Kaplan-Meier survivorship of the index group was 84% at 2 years, 73% at 5 years, and 59% at 10 years. Forty-seven percent of all failures occurred within 2 years postoperatively, and 69% occurred within 5 years postoperatively. Pediatric patients had a higher failure rate than adults (42% versus 24%). Aseptic loosening was the most common reason for failure (n = 18/32; 56%). The incidence of failure in tumor megaprostheses is similar to early published literature and the incidence of these failures is highest within the first 3 years.

LEVEL OF EVIDENCE

Therapeutic study, level IV.

Cemented rotating hinge endoprosthesis for limb salvage of distal femur tumors

We retrospectively ascertained the outcomes and complications with a cemented rotating hinge implant. Implant failure was defined as amputation of the affected limb and revision of part or all of the components. We included 77 consecutive distal femoral replacements performed between 1989 and 2004. The mean age was 42 years (range, 12-87 years) and the mean length of followup was 52 months (range, 1.5-157 months). Five-year implant survival was 84% and 10-year survival was 79%. There were 67 bone sarcomas, two soft tissue sarcomas and eight metastatic carcinomas. At followup, 54 patients had no evidence of disease, 16 were alive with disease, and seven were dead from disease. Six patients had deep infection, two of which required amputations. There were five local recurrences; three needed amputation and two soft-tissue excisions only. Three patients sustained a tibial bearing fracture and one required replacement of loose bumper. No revision was performed for stem loosening, stem fracture, or bushing wear. Musculoskeletal Tumor Society 1987 scores averaged 30 and Toronto Extremity Salvage Scores averaged 77.6 at latest followup. Cemented endoprosthesis is a reliable procedure after resection of the distal femur for tumors.

LEVEL OF EVIDENCE

Therapeutic study, level IV (case series).

Lower limb salvage surgery: modular endoprosthesis in bone tumour treatment

We retrospectively analysed 90 patients who underwent "en bloc" resection and modular endoprosthesis reconstruction in the lower limbs between 1987-2003. After proximal femur resection, reconstruction was performed with a modular endoprosthesis by Howmedica (KFTR, designed by Kotz) and modular revision endoprosthesis by W. Link or Lima-Lto (Revision system, designed by Wagner). The knee joint was reconstructed with a modular endoprosthesis (Howmedica, KFTR designed by Kotz) after distal femur or proximal tibia resection. Malignant bone tumours were present in 58 patients (64.5%), benign tumours in 16 (17.8%), metastases in 8 (8.9%), tumour-like lesions in 4 (4.4 %) and non-tumour-related destruction of the femur in 4 patients (4.4%). High-grade tumours were found in the majority of malignant bone tumours (70.7%). Treatment complications, which occurred in 26 patients, were: local recurrence of the tumour, deep infection, acetabular destruction following hemiarthroplasty, recurrent dislocations of endoprosthesis, periprosthetic fracture and hardware problems. In total, 23 patients (25.6%) died due to tumours. Endoprostheses should be considered as a treatment of choice for bone tumours in the hip and knee joint region. Advances in limb salvage surgery are, and will long continue to be, a great challenge for orthopaedic oncologists of the 21st century.

Techniques in the management of juxta-articular aggressive and recurrent giant cell tumors around the knee

AIM

Juxta-articular aggressive and recurrent giant cell tumors around the knee pose difficulties in management. This article reviews current problems and options in the management of these giant cell tumors.

METHODS

A systematic search was performed on juxta-articular aggressive and recurrent giant cell tumor. Additional information was retrieved from hand searching the literature and from relevant congress proceedings. We addressed the following issues: general consensus on early diagnosis and techniques in its management. In particular, we describe our results with resection arthrodesis performed combining the benefits of both interlocking intramedullary nail and Ilizarov fixator in the management of these tumors around the knee.

RESULTS

Mean operative age of the 22 patients undergoing resection arthrodesis was 35.63 years. Seven lesions were in the tibia and fifteen in the femur. Mean length of the bone defect was 12.34 cm. The mean external fixator index was 7.44 days/cm and the distraction index was 7.88 days/cm. Mean period of follow-up for the patients was 64.5 months. The function of the affected limb was rated excellent in 10 and good and fair in six patients each as per Enneking criteria. No local recurrence of tumor was seen. Seven complications occurred in five patients.

CONCLUSION

Two-ring construct, bifocal bone transport, and early definite plate osteosynthesis with additional bone grafting of the docking site at the end of distraction even before consolidation of the regenerate helps to reduce the problems of pin tract infections drastically. Thin-diameter long intramedullary nail in addition to preserving the endosteal blood supply also prevents mal-alignment of the regenerate. Thus resection arthrodesis using interlocking intramedullary nail and bone transport using Ilizarov fixator is cost effective and effective in achieving the desired goals of reconstruction with least complications in selected patients with specific indications.

Autoclaved tumor bone for reconstruction: an alternative in developing countries

The options for reconstruction after excision of skeletal tumors include reimplanting the autoclaved tumor-bearing bone. We asked whether such bone will survive and unite with normal bone and whether the local tumor recurrence rate increases after its use. We ascertained the functional outcome (Musculoskeletal Tumor Society score) and complications in 19 patients. After wide excision, the bony segment was autoclaved at 120 degrees for 10 minutes and reimplanted at the original defect with intramedullary nails and compression plates. Twelve of our 19 patients were available for followup. The autoclaved segment united with the normal bone in 11 of the 12 patients. No patients had fracture or resorption of the autoclaved segment. Two patients had local tumor recurrence in nearby soft tissues, apparently unrelated to the autoclaved bone. The mean functional score was 70%. Complications included fatigue failure of the nail in one patient, superficial infection in three patients, and deep infection in two patients. Reconstruction with autoclaved tumor-bearing bone is a simple and effective tool in limb salvage. This technique is a cost-effective alternative for developing countries circumventing complications of prosthetic and allograft reconstruction.

Wechsel von Tumorendoprothesen des Kniegelenks

Revision of tumour endoprostheses around the knee joint is mainly caused by aseptic loosening and deep infection. Mechanical complications have been significantly reduced by improvements in prosthetic design. The rate of aseptic loosening after distal femur or proximal tibia replacement ranges from 10% to 45% depending on the time of follow-up and prosthetic design; the success rate after revision averages 75% at midterm follow-up. The rate of infection reported in the literature varies between 2.9% and 12%. One stage revision may be considered after acute infection without signs of loosening, after which a success rate of 77.8% can be expected. Two stage revision is mainly indicated in multi-resistant microorganisms as well as septic loosening, with a success rate of 75% after 5 years. Deep infection represents the most serious complication in long-term follow-up, often leading to amputation due to soft tissue problems after tumour resection. The authors were able to confirm the minimal decrease in MSTS score despite the large number of operations (15 patients: nine females, six males; median MSTS score 84%; mean 81%).

Evaluating physical function in an adolescent bone tumor population

BACKGROUND

Survival rates for patients with bone tumors have increased dramatically over the past few decades. Unfortunately, many patients face functional limitations resulting from disease management, but there is little evidence regarding physical functioning in adolescents with bone tumors. This lack is largely due to the absence of a standardized measure for evaluating adolescent sarcoma physical functioning. This review discusses considerations in searching for a measure of adolescent physical functioning, evaluates measures previously used in assessing functional outcome in young sarcoma patients, reviews self-report measures of pediatric physical functioning, and makes recommendations for future research.

PROCEDURE

Electronic databases were searched for studies published between 1980 and 2004. Studies examining physical functioning in adolescent sarcoma patients and those describing measures of pediatric physical functioning were included.

RESULTS

The study includes measures previously used in the adolescent bone tumor literature (Musculoskeletal Tumor Society, Mankin, Groningen Activity Restriction Scale, Toronto Extremity Salvage Score [TESS]), and three measures of pediatric physical function (Functional Disability Inventory, Pediatric Outcomes Data Collection Instrument [PODCI], Activities Scale for Kids [ASK]). The TESS, PODCI, and ASK each met at least four of the outlined applicability and feasibility components.

CONCLUSION

The search for a measure of physical functioning for adolescent sarcoma patients requires an exploration of many developmental and measurement issues. Based on the sensibility review presented, the TESS, PODCI, and ASK are recommended for further evaluation of content and of the measurement properties of reliability, validity, and responsiveness, prior to their use in evaluating adolescent sarcoma patients.

Ischial weight-bearing brace after the infection of megaprosthesis a salvage method for resection arthroplasty

We report a case of successful control of the infection of megaprosthesis in the distal femur. Deep infection occurred 5 years after the resection of the osteosarcoma and reconstruction with cementless megaprosthesis. Multiple debridement and intravenous administration of antibiotics did not eradicate the infection. He developed aortitis syndrome (Takayasu's arteritis) and needed to undergo steroid therapy. Total removal of the prosthesis achieved good control of the infection, and the patient had started prednisolone therapy. The patient can walk alone with an ischial weight-bearing brace. Removal of the endoprosthesis and application of ischial weight-bearing brace may be a possible option for the treatment of infected megaprosthesis.

Epidiaphyseal versus other intercalary allografts for tumors of the lower limb

Epidiaphyseal intercalary reconstruction has become possible for bone tumors that extend into the epiphysis because advances in magnetic resonance imaging and chemotherapy allow close resection while sparing the juxtaarticular bone and joint. In a retrospective study, we questioned whether epidiaphyseal reconstructions around the knee had a clinical outcome (measured as long-term survival, complication rate, and functional score) comparable with metadiaphyseal and diaphyseal reconstructions. Between 1988 and 1999, 14 epidiaphyseal, nine metaphyseal, and 12 diaphyseal reconstructions were done, and the median followup was 7.2 years. Kaplan-Meier analysis showed a 10-year survival rate of 79% for epidiaphyseal reconstructions, which did not differ from an 89% rate for metadiaphyseal and a 75% rate for diaphyseal reconstructions. Epidiaphyseal complications included two infections, five fractures, and three nonunion treatments. Complications for all 35 grafts included three infections, 12 fractures, and nine nonunion treatments. Ultimately, six grafts failed, with infection and length of resection as predisposing factors. All epiphyseal osteotomies had tumor-free margins and no local recurrences. The mean Musculoskeletal Tumor Society score for each type of intercalary reconstruction was between 23 and 24. Because the epidiaphyseal reconstruction avoids complications associated with joint reconstruction and the results are comparable with those of other types of intercalary grafts, these reconstructions should be considered if at least 1 cm of tumor-free juxtaarticular bone can be maintained.

Role of long stem revision knee prosthesis in periprosthetic and complex distal femoral fractures: a review of eight patients

Eight patients, six with periprosthetic and two with complex distal femoral fractures (one pathological, and one with failed internal fixation) were treated with a cemented long stem revision arthroplasty prosthesis to address the issues of articular comminution, stability, alignment and early mobilisation. The average age of the patients was 78 years (range 39-81). There were no intra-operative complications. The mean hospital stay was 12 days (range 8-21). Post-operative complications included one case of posterior dislocation and one superficial infection. All patients had remarkable symptomatic relief at 3 months as indicated by the visual analogue scores. All periprosthetic fractures achieved bony union at a mean time of 3.8 months. The mean follow up was 24 months (range 14-42). The American Knee Society score revealed one 'excellent', five 'good', one 'satisfactory' and one 'poor' result. The mean loss of extension was 7.7 degrees (range 5 degrees -15 degrees ) and the mean flexion achieved was 66 degrees (range: 15 degrees to 85 degrees ). The mean alignment was 6 degrees (range 0 degrees -10 degrees ) valgus. This study highlights the role of long stem prosthesis in periprosthetic and some complex distal femoral fractures in offering stability and early mobilisation.

Uncemented tumor endoprostheses at the knee: root causes of failure

Although cemented tumor endoprostheses are the most commonly used method for reconstruction of the distal femur or proximal tibia after resection of primary bone tumors, aseptic loosening remains a common complication. Uncemented tumor prostheses may minimize this problem. We investigated the root causes of prosthetic failure for 99 patients with a fixed-hinge, bone-ingrowth Kotz Modular Femur and Tibia Resection System endoprosthesis and compared complications that led to implant failure with results in the literature. Of the 74 distal femoral implants and 25 proximal tibial implants, 25 patients had complications that resulted in prosthetic failure (removal of the prosthesis) at a median of 24.1 (range, 0.8-72.6) months. Failure was caused by prosthesis (n = 18) or oncologic-related (n = 7) complications. However, limb-salvage was possible for 87 of 99 patients. Smaller stem size in the distal femur and longer bone resection length in the proximal tibia were significantly associated with increased risk of prosthetic failure by multivariate analysis. The risk of stem fracture (6 of 99 patients) and infection (10 of 99 patients) was higher than other reports, but aseptic loosening (2 of 99 patients) was uncommon. These results suggest that although the bone-ingrowth surface of this prosthesis leads to a very low aseptic loosening rate, the higher risk of stem fracture and infection must be addressed in future implant designs.

LEVEL OF EVIDENCE

Therapeutic study, level IV-1 (case series).

Extracorporeal irradiated autogenous osteochondral graft

We examined osteochondral autografts, obtained at a mean of 19.5 months (3 to 48) following extracorporeal irradiation and re-implantation to replace bone defects after removal of tumours. The specimens were obtained from six patients (mean age 13.3 years (10 to 18)) and consisted of articular cartilage (five), subchondral bone (five), external callus (one) and tendon (one). The tumour cells in the grafts were eradicated by a single radiation dose of 60 Gy. In three cartilage specimens, viable chondrocytes were detected. The survival of chondrocytes was confirmed with S-100 protein staining. Three specimens from the subchondral region and a tendon displayed features of regeneration. Callus was seen at the junction between host and irradiated bone.

Reconstruction using an autograft containing tumour treated by liquid nitrogen

We describe a method of reconstruction using tumour-bearing autograft treated by liquid nitrogen in 28 patients. The operative technique consisted of en bloc excision of the tumour, removal of soft tissue, curettage of the tumour, drilling and preparation for internal fixation or prosthetic replacement before incubation for 20 minutes in liquid nitrogen, thawing at room temperature for 15 minutes, thawing in distilled water for ten minutes, and internal fixation with an intramedullary nail, plate or composite use of prosthetic replacement. Bone graft or cement was used to augment bone strength when necessary. The limb function was rated as excellent in 20 patients (71.4%), good in three (10.7%), fair in three (10.7%), and poor in two (7.1%). At the final follow-up six patients had died at a mean of 19.8 months after the operation, while 21 remained free from disease with a mean follow-up of 28.1 months (10 to 54). One patient is alive with disease. Bony union was seen at a mean of 6.7 months after the operation in 26 patients. Complications were encountered in seven patients, including three deep infections, two fractures, and two local recurrences. All were managed successfully. Our results suggest that this is a simple and effective method of biological reconstruction.

Periprosthetic bone remodeling around a prosthesis for distal femoral tumors: longitudinal follow-up

Serial measurements using dual-energy x-ray absorptiometry (DEXA) were undertaken to evaluate progressive periprosthetic bone loss in patients treated for primary bone tumors of the distal femur using an uncemented tumor prosthesis. Twelve patients underwent sequential DEXA analysis on average 26.5 and 90.9 months postsurgery. Changes in bone mineral density were measured in regions of interest (ROIs) around the prosthesis stem. The test-retest reliability coefficient (r) ranged from 0.92 to 0.99 for all ROI. In the most distal ROI (ROI1), 10 of 11 patients with 2 measurements showed no change or a small increase in absolute bone mineral density. The results in other ROIs were similar. This longitudinal DEXA data suggest that progressive bone resorption is not problematic with an uncemented distal femur endoprosthesis at intermediate follow-up. Key words: DEXA, stress shielding, uncemented endoprothesis, tumor, bone loss.

The modular segmental kinematic rotating hinge for nonneoplastic limb salvage

From January 1980 to July 1998, 25 patients (26 knees) were treated with an arthroplasty using a Modular Segmental Kinematic Rotating Hinge total knee prosthesis for nonneoplastic limb salvage. The indications included: nonunion of a periprosthetic femur fracture (11 knees), severe bone loss and ligamentous instability (eight knees), nonunion of a supracondylar femur fracture (four knees), acute periprosthetic fracture (one knee), fracture of a previous hinge (one knee), and prior resection arthroplasty (one knee). The average age of the patients was 72.3 years. Twenty-two arthroplasties were revisions. The average followup was 58.5 months. At the latest followup, knee extension averaged 2.4 degrees and flexion averaged 93.6 degrees. The Knee Society knee score improved from an average of 45.4 preoperatively to 75.5. Preoperatively, functional scores averaged 8.6 and improved to 25. Complications occurred in eight patients. The most common was deep infection (five patients). The use of the Modular Kinematic Rotating Hinge for nonneoplastic limb salvage represents a small proportion (0.14%) of all primary and revision knee arthroplasties done at our institution. The indications for the surgery are for a highly complex and small subset of patients. The patients in the current study gained significant improvement in overall range of motion, Knee Society knee scores, and functional scores when this prosthesis was used.

Custom cross-pin fixation of 32 tumor endoprostheses stems

The main cause of mechanical failure of primary and revision cemented tumor endoprosthetic stems is aseptic loosening. The placement of custom designed pins through the bone, the cement, and the stem can create a bone-cement-prosthesis composite that resists the rotatory stresses that lead to aseptic loosening. At risk situations include large primary reconstructions where the residual short metaphyseal articular segments lack sufficient length and cortical contact to provide lasting fixation, and revision prostheses that are to be recemented into straight diaphyseal segments that already have experienced aseptic loosening. Current modular tumor endoprosthetic systems have improved availability and allow for some intraoperative flexibility, but they do not provide solutions for these at risk scenarios. Additional customization is necessary. We report on the 16-year experience with 32 custom cross-pin stems at the University of California, Los Angeles (UCLA). Twenty of these patients have been followed up for more than 2 years. There were three mechanical failures, three patients were lost to followup, and five patients died of disease. There have been no cases of aseptic loosening in this series. Cross-pin fixation has been effective when used in carefully selected cases.

Effects of liquid nitrogen treatment on the proliferation of osteosarcoma and the biomechanical properties of normal bone

To overcome problems of autografts for reconstruction in the presence of malignant bone and soft tissue tumors, we devised a method for treating autografts that utilizes the hypothermic effect of liquid nitrogen. We measured temperature changes inside the bone at each condition and established a one-cycle liquid nitrogen protocol that included 20 min in liquid nitrogen, 15 min in room air, and 15 min in physiological saline. The proliferation potential of the tumor cells treated with the liquid nitrogen method was examined by means of bromodeoxyuridine (BrdU) immunostaining. Tumor proliferation potential in vivo was examined in nude mice. Based on the results we concluded that the tumor cells died out as a result of the liquid nitrogen method. Regarding compression strength there was no significant difference between intact bone and liquid nitrogen-treated bone, whereas the strength of the autoclaved bone was decreased. Scanning electron microscopic examination of the fracture surface of the autoclaved bone after the compression test showed an irregular, uneven surface, whereas that of the liquid nitrogen-treated bone was smooth and fine-grained. This might be one of the reasons for the discrepancy in compression strength.

Histological and radiological analysis of autoclaved bone 2 years after extirpation

We examined grafted distal femoral autoclaved bone radiologically and histologically 24 months after surgery. The patient was a 16-year-old boy with osteoblastic-type osteosarcoma in the distal part of the left femur. The patient received pre- and postoperative chemotherapy and underwent limb reconstruction surgery using an autoclaved autograft. He was forced to undergo hip disarticulation because of local recurrence in the soft tissue. Radiologically and histologically, we were able to detect newly formed bone at the site of the distal junction and surrounding the autoclaved autograft, although most of the autoclaved bone remained without substitution even 24 months after implantation. The layer of newly formed bone surrounding the autoclaved autograft was so thin that it seemed to be ineffective for weight-bearing. Drilling into the autoclaved autograft appeared to promote little bone regeneration inside the autoclaved autograft. A bone scintigram showed newly formed bone around the autoclaved autograft, but the scan tended to exaggerate such bone formation beyond that actually confirmed by histological examination. We should be careful when applying autoclaved bone for weight-bearing parts.

Distal femur resection with endoprosthetic reconstruction: a long-term followup study

The distal femur is a common site for primary and metastatic bone tumors and therefore, it is a frequent site in which limb-sparing surgery is done. Between 1980 and 1998, the authors treated 110 consecutive patients who had distal femur resection and endoprosthetic reconstruction. There were 61 males and 49 females who ranged in age from 10 to 80 years. Diagnoses included 99 malignant tumors of bone, nine benign-aggressive lesions, and two nonneoplastic conditions that had caused massive bone loss and articular surface destruction. Reconstruction was done with 73 modular prostheses, 27 custom-made prostheses, and 10 expandable prostheses. Twenty-six gastrocnemius flaps were used for soft tissue reconstruction. All patients were followed up for a minimum of 2 years. Function was estimated to be good or excellent in 94 patients (85.4%), moderate in nine patients (8.2%), and poor in seven patients (6.4%). Complications included six deep wound infections (5.4%), six aseptic loosenings (5.4%), six prosthetic polyethylene component failures (5.4%), and local recurrence in five of 93 patients (5.4%) who had a primary bone sarcoma. The limb salvage rate was 96%. Distal femur endoprosthetic reconstruction is a safe and reliable technique of functional limb sparing that provides good function and local tumor control in most patients.

Osteosarcoma of the proximal humerus: long-term results with limb-sparing surgery

The purpose of the current study was to analyze the long-term oncologic and functional results and complications associated with limb-sparing surgery and endoprosthetic reconstruction for 23 patients with osteosarcoma of the proximal humerus. There was one Stage IIA lesion, 18 Stage IIB lesions, and four Stage III lesions in this study group. Twenty-two patients were treated with an extraarticular resection that included the deltoid and rotator cuff and one patient was treated with an intraarticular resection that spared the shoulder abductors. In all these patients, the proximal humerus was reconstructed with a cemented endoprosthetic replacement that was stabilized via a technique of static suspension (Dacron tapes) and dynamic suspension (muscle transfers). At latest followup (median, 10 years), 15 patients (65%) were alive without evidence of disease. There were no local recurrences. Prosthetic survival was 100% for the 15 survivors. The Musculoskeletal Tumor Society upper extremity functional score ranged from 24 to 27 (80%-90%). All shoulders were stable and pain-free. Elbow and hand function were preserved in all patients. The most common complication was a transient neurapraxia (n = 8). En bloc extraarticular resection and endoprosthetic reconstruction is a safe and reliable method of limb-sparing surgery for patients with high-grade extracompartmental osteosarcoma of the proximal humerus.

Instability after major tumor resection: prevention and treatment

Instability is a significant problem after resection of musculoskeletal tumors. In this article, the authors discuss the issue of instability after resections of the pelvis, the femur, and the proximal tibia. The options for reconstruction in each area are discussed along with a review of the literature and a description of the authors' preferred approach.

Long-term followup of uncemented tumor endoprostheses for the lower extremity

Between 1982 and 1989, 100 primary lower limb reconstructions were done using the Kotz Modular Femur Tibia Reconstruction System after resection of a malignant tumor. In 32 patients a proximal femur prosthesis was implanted, in 40 patients a distal femur prosthesis was implanted, in 19 patients a proximal tibia component was implanted, in four patients a total femur prosthesis was implanted, and in five patients a total knee prosthesis was implanted. The Kaplan-Meier estimate of the overall survival rate of the prostheses was 85% after 3 years, 79% after 5 years, and 71% after 10 years. The most common reason for implant failure was aseptic loosening in 27% of patients (11 patients; range, 10-121 months) after the initial operation. The other reasons for revision surgery were implant fracture (n 5 4) and infection (n 5 4). Early repair of prostheses-related minor complications, such as worn polyethylene bushings, resulted in a statistically significant reduction of implant failure. After a median followup of 127.5 months after the initial surgery, 51 patients had died and eight patients were lost to followup. Forty-one patients were evaluated clinically and radiologically using the Musculoskeletal Tumor Society score and the radiologic implant evaluation system of the International Symposium on Limb Salvage; these 41 patients had a mean of 80% (range, 40%-100%) of the normal functional capability.

Comparison of two methods of reconstruction for primary malignant tumors at the knee: a sequential cohort study

BACKGROUND AND OBJECTIVES

The purpose of this study was to compare the complications and functional outcome associated with the use of an irradiated allograft-implant composite or a bone-ingrowth modular tumor prosthesis for replacement of the knee joint after resection of a bone sarcoma from the distal femur or proximal tibia.

METHODS

Eleven patients initially received an allograft reconstruction, followed by 64 treated with a tumor prosthesis. The primary analysis concerned reconstructive failure, defined by the requirement for removal of the original construct. Functional outcome was assessed by using the 1987 Musculoskeletal Tumor Society rating system.

RESULTS

Reconstructive failure occurred in 6 of 11 (55%) allograft constructs compared with 10 of 64 (16%) tumor prostheses (P = 0.009). Failures were due to infection (2 of 11 allografts versus 4 of 64 prostheses; P = 0.2) or mechanical complications (4 of 11 allograft fractures versus 5 of 64 broken prosthetic stems and 1 aseptically loose prosthesis; P = 0.03). The limb salvage rate was 95% (61 of 64) for patients with a tumor prosthesis compared with 64% (7 of 11) for those with an allograft (P = 0.007). Patients with a tumor prosthesis had a better functional outcome with a mean score of 75% compared with 57% for those with an allograft reconstruction (P = 0.006).

CONCLUSIONS

This comparative study suggests that limb salvage surgery at the knee has a better and more predictable outcome with a tumor prosthesis than with an allograft-implant reconstruction.

Plantar and dorsal foot loading measurements in patients after rotationplasty

OBJECTIVE

The present study investigated the plantar and dorsal foot loading patterns inside the prosthesis of patients after rotationplasty.

DESIGN

In vivo foot pressure distribution measurements during free walking in rotationplasty patients at an average follow-up of 10.4 years after surgery.

METHODS

Fourteen subjects participated in the study and were measured during free walking. Capacitive pressure sensitive insoles were worn inside the shaft of the prosthesis either on the plantar or the dorsal aspect of the foot. Between 5 and 15 steps (mean 10.5) during full gait were selected and averaged to present a typical loading pattern for the individual patient.

RESULTS

The measurements were reproducible and indicated that the main loading areas of the rotated foot inside the prosthesis are medially on the dorsal aspect and in the heel and toe region or the heel and midfoot region on the plantar aspect. The dorsal loading area was smaller than the plantar area (P=0.003). The force was higher on the plantar than on the dorsal aspect (P=0.005) but the loading time was shorter (P=0.008). In patients with callosities the high pressure areas coincided with the affected regions.

CONCLUSIONS

The information gained from the pressure measurements support the understanding of foot loading characteristics in this anatomically and biomechanically unusual situation. This knowledge may be used to support the fitting process of new prosthetic designs for patients after rotationplasty.

RELEVANCE

Foot loading capacity is one of the main factors limiting the activity level of rotationplasty patients. Therefore, a better understanding of foot loading characteristics might help to prevent overloading of certain foot structures and eventually improve the prosthetic fit with a direct benefit to the individual patient.

Survivorship and radiographic analysis of knee osteoarticular allografts

An evaluation of long-term survival and radiographic deterioration of 118 knee osteoarticular allografts in 114 patients was performed. Radiographic analysis was done according to the Musculoskeletal Tumor Society grading system. A failure was defined as when the allograft was removed during a revision procedure or amputation. Ten patients were lost to followup during the first 2 years after surgery. Eighteen patients without allograft failures died of complications related to the tumor. Twenty-six allografts failed because of infection (13 allografts), local recurrence (eight allografts), massive resorptions (three allografts) and fractures (two allografts). Sixty-four allografts still were in place at a mean of 98 months (range, 36-360 months) after implantation. The Kaplan-Meier 5-year survival rate for the knee osteoarticular allografts was 73% and the limb preservation rate was 93%. The mean radiographic score was 83%. Sixty-four percent of the allografts showed no radiologic changes or minor articular deterioration. Fourteen percent had narrowing of the joint space of more than 2 mm, and 22% had some form of subchondral bone collapse. Five patients required joint resurfacing to preserve the original allograft. Most of the allograft failures occurred during the first 4 years, and the allograft survival rate for the current series remained unchanged after 5 years.

Function and complications after ablative and limb-salvage therapy in lower extremity sarcoma of bone

BACKGROUND AND OBJECTIVES

The functional results and the complications after several limb-saving and ablative treatments because of lower extremity bone sarcoma were evaluated.

METHODS

Seventy-seven surviving patients were evaluated according to the MSTS (American Musculoskeletal Tumor Society) functional rating system. Fifty-two patients had limb-saving and 25 had ablative therapy. Median follow-up was 97 months in the limb-saving group and 112 months in the ablative group.

RESULTS

Functional results in the limb-saving group were significantly better than in the ablative group (P = 0.0001). Functional results in patients with tumors about the knee joint were significantly better (P = 0.0064) after limb-saving surgery (i.e., endoprosthesis, knee arthrodesis, or rotationplasty) compared to functional results after ablative surgery (i.e., hip or knee disarticulation or above-the-knee amputation). Complications were 3 times more common after limb-salvage procedures and 4 times more common after endoprosthetic reconstructions compared to after ablative procedures. Complications after limb-saving therapy were fewest in tumors about the knee joint. In 3/28 patients, the endoprosthetic reconstruction had to be converted to an amputation.

CONCLUSIONS

Functional results were significantly better after limb-saving compared to after ablative therapy. Complications, however, were more common after limb-saving therapy.

Electromyographic and gait analysis of forty-three patients after rotationplasty

BACKGROUND

Rotationplasty is considered to be a treatment option for patients who have had a primary malignant bone tumor of the distal part of the femur or the proximal part of the tibia. The present study was performed to evaluate the muscle activity, the kinetics (range of motion of the hip and knee joints), and the kinematics (joint moments) after rotationplasty and to determine whether there was an association between these parameters and the functional outcome.

METHODS

Forty-three patients who had been managed with rotationplasty for the treatment of a femoral or tibial bone tumor were evaluated clinically and functionally. The mean age (and standard deviation) at the time of follow-up was 24.4 +/- 10.7 years (range, eight to sixty-eight years), the mean age at the time of the procedure was 17.8 +/- 10.2 years (range, seven to sixty-three years), and the mean duration of follow-up was 6.7 +/- 4.9 years (range, 0.7 to eighteen years). Instrumented gait and electromyographic analyses were performed. The qualitative data were compared with the functional outcome, which was determined with the functional evaluation score of the Musculoskeletal Tumor Society.

RESULTS

Gait analysis revealed a fairly normal walking pattern with a slight limp and a lateral lean of the trunk over the ipsilateral limb that led to a reduced joint moment in the hip (moment on involved side, 68 percent [compared with a control group]; moment on uninvolved side, 81 percent). The ranges of motion of the hips (uninvolved side, 42.0 +/- 8.2 degrees; involved side, 42.4 +/- 8.0 degrees) and the knees (uninvolved side, 59.7 +/- 5.0 degrees; involved side [former ankle joint], 58.1 +/- 11.6 degrees) were symmetrical even though the knee-motion pattern of the involved limb indicated a slightly reduced extensor mechanism in 51 percent (twenty-two) and a markedly reduced extensor mechanism in 35 percent (fifteen) of the forty-three patients. Electromyography revealed function of the muscles of the involved limb, with comparable amplitudes in the involved and uninvolved limbs. The leg muscles of the involved limb were active in the stance phase (the soleus and the lateral and medial heads of the gastrocnemius) and the swing phase (the peroneus longus and the tibialis anterior) according to their function in relation to the new knee joint. The patients had a good functional result, with a mean score of 23.9 +/- 2.7 of 30 points. With the numbers available for study, we could not show the duration of follow-up to be related to the overall outcome, but the age at the time of the operation was related to the total functional score as well as to gait and walking ability (p < 0.05).

CONCLUSIONS

The results of the electromyographic and gait analyses demonstrated good functional restoration of gait following rotationplasty.

Limb-saving surgery, survival, and prognostic factors for osteosarcoma: the Hungarian experience

BACKGROUND AND OBJECTIVES

There are many factors thought to have an influence on the prognosis of osteosarcoma that have been reported in the literature. Their significance, however, still remains controversial in most cases. Experience with osteogenic sarcoma (OS) was reviewed in order to evaluate surgical results and survival and to determine the prognostic factors.

METHODS

Ninety-six patients with high-grade osteosarcoma of the extremities were treated between 1986 and 1997 in the authors' institution. They were divided into 3 groups: In group I, all 75 patients with nonmetastatic OS received intensive chemotherapy (high-dose methotrexate, doxorubicin, ifosfamide, and cisplatin) and underwent surgery. In group II, 9 patients already had metastases at the time of referral. In group III, 12 patients received chemotherapy in delayed or suboptimal form. Results and Conclusions In group I, there were local recurrences in 3 patients (7%) and metastases in 8 patients (20%) with limb-saving, whereas these numbers were 1 (3%) and 14 (38%) in those who had amputation. The 5-year disease-free survival (DFS) was 72% and 69% in the limb-saving and amputation groups, respectively. In groups II and III, 5-year DFS was extremely poor, 10% and 20% only, underlining the importance of stage and intensity of chemotherapy, respectively. With univariate analysis, sex, duration of symptoms, and radiographic appearance of OS had no prognostic value, whereas tumor volume <60 cm(3), wide or radical surgical margin, distal location of OS, cartilagineous ground substance <20%, and response to chemotherapy were positive prognostic factors. The last 4 variables maintained their significance in the multivariate Cox model as well. Age >30 years showed indirect negative influence on the final outcome through enhanced intolerability to the drugs and less cooperability of the patients. The results on survival with limb-saving surgery were well comparable with those of amputation.

Intraoperative extracorporeal autogenous irradiated bone grafts in tumor surgery

There are several procedures for reconstruction of bony defects after resection of malignant musculoskeletal tumors. The clinical results of intraoperative extracorporeal autogenous irradiated bone grafts in 20 patients with musculoskeletal tumors are discussed. The authors' method of treatment consists of: (1) wide en bloc resection of the tumor with involved bone; (2) curettage of the tumor from the resected bone; (3) extracorporeal irradiation with 50 Gy as a bolus single dose to the isolated bone; and (4) reimplantation of the irradiated bone into the host with fixation devices. Twelve bone sarcomas and eight soft tissue sarcomas with bone involvement were treated surgically with this reconstruction method after wide resection of the tumors. The irradiated bone was used as an intercalary graft in seven cases, as an osteoarticular graft in 11 cases, and as a hemicortical graft in two cases. The theoretical advantages of this method are certain sterilization of tumor cells with radiation, easy availability and good adaptation of size and shape, no risk of disease transmission, preservation of bone stock and ligamentous tissue, and no immunologic reaction. Radiologically, bony union occurred in 23 of 29 (79%) osteotomy sites. The overall radiographic evaluation rating was 74% and the functional rating was 73% according to the International Society of Limb Salvage rating system. Nonunion (20%) and infection (15%) were the two major complications. Preservation of the tendon insertions and ligamentous structures of the irradiated bone seemed to restore excellent joint function. No local recurrence was detected from the irradiated bones during the mean followup of 45 months. These results indicate intraoperative extracorporeal irradiated bone graft can be a widely applicable method for reconstruction in tumor surgery.

Osteosarcoma: oncologic and functional results. A single institutional report covering 22 years

BACKGROUND AND OBJECTIVES

The oncologic and functional results in patients treated because of osteosarcoma (OS) were evaluated.

METHODS

Fifty-one patients with high-grade OS were treated between 1974 and 1996 at our hospital. All patient records were studied, and the surviving patients were evaluated according to the American Musculoskeletal Tumor Society functional rating system. The majority of patients received adjuvant chemotherapy (prior to 1983) or neoadjuvant chemotherapy (from 1983). Until 1987, all patients with extremity OS had ablative surgery; from 1987, the majority had limb-saving surgery. Lung metastases were resected in most cases.

RESULTS

Overall 2-year and 5-year disease-free survival (DFS) rates were 27 of 51 and 16 of 42, respectively. Patients with vertebral or pelvic OS or contaminated margins after resection had a very bad outcome. In all other subgroups, including patients with various types of chemotherapy, response to chemotherapy, diameter of tumor, presence or absence of metastatic spread, and location of tumor, a 5-year DFS of about 50% was found. Recurrent disease in patients who had achieved a 2-year disease-free interval was relatively low (4/23 patients).

CONCLUSIONS

Survival in our series was worse than in most other studies. A very bad outcome was found in patients with vertebral or pelvic OS or with contaminated margins after resection.

A rotating-hinge knee replacement for malignant tumors of the femur and tibia

We evaluated the 2- to 7-year results of a rotating-hinge knee replacement after excision of malignant tumors of the knee joint. There were 25 distal femoral and 7 proximal tibial replacements. The 5-year prosthetic survival for distal femoral replacements was 88%, compared with 58% for proximal tibial replacements. Seven patients underwent prosthetic exchange: 1 for aseptic loosening, 2 for wound slough and perioperative infection, and 4 for articulating component failure. One patient underwent above-knee amputation owing to skin necrosis. The median functional scores at the latest follow-up were 27 by the International Society of Limb Salvage evaluation system and 80 by the Hospital for Special Surgery Knee Score system. This implant is a promising choice for joint reconstruction after excision of tumors at the knee joint.

Relationship between magnitude of resection, complication, and prosthetic survival after prosthetic knee reconstructions for distal femoral tumors

BACKGROUND AND OBJECTIVES

Limb-sparing surgery has become the preferred surgical treatment of malignant bone tumors. The objective of this study was to evaluate factors that influence the morbidity and outcome of prosthetic knee replacement after resection of malignant tumors of the distal femur.

METHODS

Eighty-two patients who had a resection of malignant tumor of the distal femur and implantation of a segmental knee prosthesis (minimum follow-up, 2 years) were retrospectively reviewed.

RESULTS

Twenty-nine patients (35%) underwent 32 prosthetic revisions, 6 from perioperative wound complications, 13 from aseptic loosening, and 13 from other complications. The 3-, 5-, and 10-year Kaplan-Meier prosthetic survival rates were 82%, 71%, and 50%, respectively. On univariate analysis, patients who had more than 40% resection of the distal femur (P = 0.010) and those who had all their vasti muscles resected (P = 0.011) had significantly worse prosthetic survivals than the others. On multivariate analysis, resection of more than 40% of the distal femur was a significant negative prognostic factor for prosthetic survival (P = 0.017). Aseptic loosening was the primary cause of late prosthetic failure. Differences in the magnitude of resection influenced prosthetic survivorship more than prosthetic design.

CONCLUSIONS

In the distal femoral endoprosthetic replacement, higher short- and long-term complications were found after extensive resections. Aseptic loosening was the primary cause of prosthetic failure.