Failure rates and functional results for intercalary femur reconstructions after tumour resection.

PURPOSE: To compare the results for patients treated with intercalary endoprosthetic replacement (EPR) or intercalary allograft reconstruction for diaphyseal tumours of the femur in terms of: (1) reconstruction failure rates; (2) cause of failure; (3) risk of amputation of the limb; and (4) functional result. METHODS: Patients with bone sarcomas of the femoral diaphysis, treated with en bloc resection and reconstructed with an intercalary EPR or allograft, were reviewed. A total of 107 patients were included in the study (36 EPR and 71 intercalary allograft reconstruction). No differences were found between the two groups in terms of follow-up, age, gender and the use of adjuvant chemotherapy. RESULTS: The probability of failure for intercalary EPR was 36% at 5 years and 22% for allograft at 5 years (p = 0.26). Mechanical failures were the most prevalent in both types of reconstruction. Aseptic loosening and implant fracture are the main cause in the EPR group. For intercalary allograft reconstructions, fracture followed by nonunion was the most common complication. Ten-year risk of amputation after failure for both reconstructions was 3%. There were no differences between the groups in terms of the mean Musculoskeletal Tumor Society score (27.4, range 16-30 vs. 27.6, range 17-30). CONCLUSIONS: We have demonstrated similar failure rates for both reconstructions. In both techniques, mechanical failure was the most common complication with a low rate of limb amputation and good functional results. LEVEL OF EVIDENCE: Level III, therapeutic study.

Proximal humerus chondrosarcoma.Long-term clinical and oncological outcomes. / Condrosarcoma de húmero proximal. Resultados clínicos y oncológicos a largo plazo.

INTRODUCTION: The proximal humerus is a common site for primary bone sarcomas, of which chondrosarcoma represents 15%. There are few reports about this select group of tumours. We set out to analyse a group of patients with proximal humerus chondrosarcoma treated with surgery and to assess their long term surgical and oncological outcomes. MATERIAL AND METHODS: A retrospective review was performed and all patients with a proximal humerus chondrosarcoma treated with surgery were included in the study. Overall survival and local recurrence rates were analyzed. Post-operative complications were recorded and limb salvage surgery failures classified according to the Henderson classification. RESULTS: 37 patients were included in the study. The median age was 46 years (SD: 15.6, range: 17-24), 24 (65%) were female and the mean follow-up was 8.5 years (SD: 6.4, range: 2 -26). Eighteen patients were classified as grade 1 (49%), 15 as grade 2 (40%), 2 as grade 3 (5%) and 2 dedifferentiated chondrosarcomas (5%). The 10-year overall survival was 94.5% and the 10-year event-free survival was 84.5%. Five patients developed local recurrences (13%) and none of them was grade 1. The reconstruction failure rate was 27% at 5 years and 34% at 10 years. There were no complications or local recurrence in patients treated with curettage. CONCLUSION: Proximal humerus chondrosarcoma presented high survival rates. Curettage and bone grafting is a safe procedure, with low risk of complications and local recurrence for grade 1 chondrosarcomas and should be the first indication for the proximal humerus. Reconstruction of the proximal humerus after a wide resection has a 5-year failure rate of 27% and 10-year failure rate of 34%.

Modular prosthesis reconstruction after tumour resection, evaluation of failures and survival. / Reconstrucción con prótesis modulares posterior a una resección oncológica. Evaluación de los fracasos y análisis de la supervivencia.

OBJECTIVE: To analyze a series of patients with bone tumours reconstructed with modular prostheses and to evaluate: 1) Survival of the implant. 2) Causes of failure. 3) Complication rates. 4) Limb salvage overall survival. 5) Functional results and full weight bearing. MATERIALS AND METHODS: A retrospective study from longitudinally maintained oncology databases was undertaken. All patients with bone tumours reconstructed with endoprosthesis were analysed. A toal of 106patients matched the inclusion criteria. They were divided into groups: group 1, primary bone tumours; group 2, bone metastasis; group 3, osteoarticular allograft reconstruction revisions. The type of failures were classified according to Henderson et al. (2014) and functional results assessed by the Musculoskeletal Tumor Society (MSTS). Demographic analysis, survival and the differences between groups were recorded. RESULT: The mean follow-up of the patients was 68 months. Mean age was 43 years. Overall implant survival was 86.4% at 2 years (95% CI: 79-94) and 73% at 5 years (95% CI: 60-80). Nineteen patients (18%) developed a prosthetic failure. The limb salvage overall survival was 96% at 5 years (95% CI: 91-99). The mean functional results according to the MSTS was 24 and mean time to full weight bearing was 2.3 weeks. CONCLUSIONS: Limb conservation surgery and endosprosthetic reconstruction is a valid option for patients with bone tumours with failure rates similar to other reconstruction methods.

In Vitro Comparative Study Between Conventional and Computer-Assisted Surgery Methods for Planning and Resection of Bone Sarcomas.

This poster aims to achieve an "in vitro" comparative study between three methods: 2D digital images planning and execution without navigation (freehand with ruler and caliper), 3D planning and execution without navigation (freehand with ruler and caliper) and 3D planning and execution guided with navigation. 3D planning and navigated procedures potentially improve sarcoma resection.

Structural allograft reconstruction of the foot and ankle after tumor resections.

BACKGROUND: Structural allografts have been used to correct deformities or to fill bone defects secondary to tumor excisions, trauma, osteochondral lesions, or intercalary arthrodesis. However, the quality of published evidence supporting the use of allograft transplantation in foot and ankle surgery has been reported as fair. The purpose of this study was to report the overall survival of structural allograft in the foot and ankle after tumor resection, and the survival according to the type of allograft and the complication rates in the medium to long term. MATERIALS AND METHODS: From January 1989 to June 2011, 44 structural allograft reconstructions of the foot and ankle were performed in 42 patients (28 men and 14 women) due to musculoskeletal tumor resections. Mean age at presentation was 27 years. Mean follow-up was 53 months. Demographic data, diagnosis, site of the neoplasm, operations performed, operative complications, outcomes after surgery, date of last follow-up evaluation, and local recurrences were reviewed for all patients. Regarding the type of 44 allograft reconstructions, 16 were hemicylindrical allografts (HA), 12 intercalary allografts (IA), 10 osteoarticular allografts (OA), and 6 were total calcaneal allograft (CA). RESULTS: The overall allograft survival rate, as calculated with the Kaplan-Meier method, at 5 and 10 years was 79 % (95 % CI 64-93 %). When allocated by type of allograft reconstruction the specific allograft survival at 5 and 10 years was: 83 % for CA, 80 % for HA, 77 % for OA, and 75 % for IA. The complications rate for this series was 36 % including: articular failure, local recurrence, infection, fracture and nonunion. CONCLUSION: This study showed that structural allograft reconstruction in the foot and ankle after tumor resection may be durable with a 79 % survival rate at 5 and 10 years. The two types of allografts that showed better survival rate were hemicylindrical allografts (80 %) and calcaneus allografts (83 %). The highest complication rates occurred after calcaneus allografts and osteoarticular allografts. LEVEL OF EVIDENCE: IV.

Oncologic and clinical outcomes in pelvic primary bone sarcomas treated with limb salvage surgery.

PURPOSE: We propose to study a group of patients with primary bone sarcoma of the pelvis treated with limb salvage surgery and analyze overall survival, local recurrence rates and functional outcomes. METHODS: A retrospective review was performed, and all patients diagnosed with pelvic primary bone sarcomas between 1990 and 2012 were analyzed. Patients treated with limb salvage surgery and with a minimum of 12-month follow-up for patients alive were included. The overall survival and the local recurrence rate were calculated for the assessment of oncological results. The associations with gender, age, histological grade, type of surgery, margins chemotherapy response and use of navigation were examined. RESULTS: Fifty-two patients were included in the study. The mean age was 37 years (range 10-82), and mean follow-up was 44 months (range 8-189). Forty-five (86 %) tumors were histologically classified as high-grade sarcomas, four (8 %) as low-grade sarcomas and three (6 %) as dedifferentiated sarcomas. Cancer-specific overall survival was 37.5 % for 5 years and 31 % for 10 years. Local recurrence rate was 30 %. High-grade tumors and chemotherapy necrosis below 90 % were negative prognosis factor. Postoperative complication rate was 34.5 % (n:18), being deep infection the most prevalent (n:13). Reconstruction of the pelvis after an oncology resection for primary pelvic sarcomas increased the incidence of complication significantly (p < 0.001). CONCLUSION: Primary bone sarcomas involving the pelvis are suggestive of a high-grade tumor and present poor oncologic outcomes. Pelvic reconstruction after a limb salvage surgery is associated with a high risk of complication. LEVEL OF EVIDENCE: Case series, Level IV.

Tratamiento quirúrgico de los tumores malignos y localmente agresivos del tercio proximal del peroné. Resultados oncológicos y evaluación funcional / Surgical treatment of locally aggressive and malignant tumors of the proximal third of the fibula. Oncology results and functional evaluation

Introducción. Los tumores óseos malignos o benignos localmente agresivos del tercio proximal del peroné son infrecuentes y generalmente su tratamiento es quirúrgico. Cuando se requiere una resección en bloque, la estabilidad de la rodilla puede comprometerse por afectación del complejo posterolateral. Material y métodos. Se analizaron 28 pacientes operados de manera consecutiva por un tumor óseo en el tercio proximal de peroné entre los años 1980 y 2006 (osteosarcoma: 9, TCG: 9, sarcoma de Ewing: 8 y condrosarcoma: 2). El 61% eran varones y la edad media fue de 21 años (rango: 8-60). El seguimiento promedio fue de 86 meses. El complejo posterolateral fue reinsertado a nivel de la metáfisis tibial. Los pacientes fueron evaluados funcionalmente con la escala Musculoskeletal Tumor Society (MSTS). Resultados. La supervivencia global fue del 89%, con un índice de recidiva local del 11% y un porcentaje de amputaciones secundarias del 6% a los 7 años de seguimiento promedio. El resultado promedio del MSTS fue del 93%. Cinco pacientes sufrieron secuelas neurológicas, 3 de tipo permanente. Ningún paciente sufrió inestabilidad subjetiva ni insuficiencia vascular. Conclusiones. La resección en bloque del peroné proximal en el tratamiento de los tumores óseos agresivos o malignos depara un buen control local de la enfermedad y una supervivencia a los 7 años, en los casos malignos, del 89%. La reinserción del complejo posterolateral a nivel tibial supone una buena estabilidad de la rodilla, sin secuelas funcionales a largo plazo (AU)

Introduction. Proximal fibula malignant and locally aggressive benign bone tumors are uncommon and usually treat by surgery. Bloc resection of the knee can compromise knee stability due to of the resection of the posterolateral ligament complex. Material and methods. We analyzed 28 consecutive patients treated for a proximal fibula bone tumor between 1980 and 2006 (osteosarcoma: 9, giant cell tumor: 9, Ewing sarcoma: 8 and chondrosarcoma: 2). Sixty-one percent were male and the median age was 21 years (range: 8-60). The mean follow-up was 86 months. The posterolateral complex was reinserted at tibial metaphyseal level. Patients were evaluated functionally using the Musculoskeletal Tumor Society scale (MSTS). Results. Overall survival rate was 89%, local recurrence rate was 11%, and secondary amputation rate was 6% at 7 years of median follow-up. The average MSTS score was 93%. Five patients had neurological complications. No patient experienced subjective instability or vascular insufficiency. Conclusions. Bloc resection of the proximal fibula for the treatment of aggressive or malignant primary bone tumors allowed us to obtain local tumor control, and overall survival rate for sarcomas of 89% at 7 years. The posterolateral ligament complex tibial reinsertion provided functional knee stability without major functional consequences in the medium term (AU)

[Surgical treatment of locally aggressive and malignant tumors of the proximal third of the fibula. Oncology results and functional evaluation]. / Tratamiento quirúrgico de los tumores malignos y localmente agresivos del tercio proximal del peroné. Resultados oncológicos y evaluación funcional.

INTRODUCTION: Proximal fibula malignant and locally aggressive benign bone tumors are uncommon and usually treat by surgery. Bloc resection of the knee can compromise knee stability due to of the resection of the posterolateral ligament complex. MATERIAL AND METHODS: We analyzed 28 consecutive patients treated for a proximal fibula bone tumor between 1980 and 2006 (osteosarcoma: 9, giant cell tumor: 9, Ewing sarcoma: 8 and chondrosarcoma: 2). Sixty-one percent were male and the median age was 21 years (range: 8-60). The mean follow-up was 86 months. The posterolateral complex was reinserted at tibial metaphyseal level. Patients were evaluated functionally using the Musculoskeletal Tumor Society scale (MSTS). RESULTS: Overall survival rate was 89%, local recurrence rate was 11%, and secondary amputation rate was 6% at 7 years of median follow-up. The average MSTS score was 93%. Five patients had neurological complications. No patient experienced subjective instability or vascular insufficiency. CONCLUSIONS: Bloc resection of the proximal fibula for the treatment of aggressive or malignant primary bone tumors allowed us to obtain local tumor control, and overall survival rate for sarcomas of 89% at 7 years. The posterolateral ligament complex tibial reinsertion provided functional knee stability without major functional consequences in the medium term.

[Survival and complications analysis of 97 patients with bone metastases treated surgically]. / Análisis de sobrevida y complicaciones en 97 pacientes con metástasis óseas tratados quirúrgicamente.

BACKGROUND: The purpose of this paper is to assess the survival and the different factors predisposing to increased local and overall complications in a group of patients treated surgically for bone metastases. MATERIAL AND METHODS: A total of 97 patients were included in our study, 45 females and 52 males. Mean age was 59 years (range 22-81) and the mean follow-up was 23 months (range 3-76). Were performed 104 surgical interventions. Patient survival was estimated with the Kaplan-Meier method. Complications, recurrences and the most significant factors were analyzed. RESULTS: Overall patient survival was 73% at one year, 47% at 2 years, and 6% at 5 years. Patient survival was greater in patients with a histologic diagnosis of metastatic renal cancer (p > 0.05) and a higher incidence of local relapses (p > 0.05). Intralesional surgery significantly affected the relapses. CONCLUSIONS: Patients with metastatic renal cancer had the greatest survival rate. However, they were associated with a higher rate of local relapses and postoperative failure.

Usefulness of remote magnetic navigation for ablation of ventricular arrhythmias originating from outflow regions.

Monomorphic ventricular tachycardia (VT) and symptomatic monomorphic PVCs originating from the region of the right and left outflow tracts are increasingly treated by radiofrequency (RF) catheter ablation. Technical difficulties in catheter manipulation to access these outflow tract areas, very accurate mapping and reliable catheter stability are key issues for a successful treatment in this vulnerable region. VT ablation from the aortic sinus cusp (ASC) in particular carries a significant risk of perforation, of creating left coronary artery injury and of damage to the aorta and the aortic valve.This case series describes RF ablation of VT originating in the outflow region using the remote magnetic navigation system (MNS). Potential advantages of the MNS are catheter flexibility, steering accuracy and reproducibility to navigate to a desired location with a low probability of perforating the myocardium. This report supports the idea of using advanced MNS technology during RF ablation in regions which are difficult to reach and thin walled, such as parts of the outflow tract and the ASC. (Neth Heart J 2009;17:245-9.).

Magnetic assisted navigation in electrophysiology and cardiac resynchronisation: a review.

Magnetic assisted navigation is a new innovation that may prove useful in catheter ablation of cardiac arrhythmias and cardiac resynchronization therapy. The ability to steer extremely floppy catheters and guidewires may allow for these to be positioned safely in previously inaccessible areas of the heart. The integration of other new technology, such as image integration and electroanatomic mapping systems, should advance our abilities further. Although studies have shown the technology to be feasible, with the advantage to the physician of decreased radiation exposure, studies need to be performed to show additional benefit over standard techniques.

Pulmonary vein antrum isolation guided by phased-array intracardiac echocardiography: A third way to do PV ablation.

BACKGROUND: Pulmonary vein isolation (PVI) has emerged as an important strategy in the treatment of patients with atrial fibrillation (AF). The two most frequently used techniques are segmental PVI and left atrial circumferential ablation. AIM: To describe and discuss pulmonary vein antrum isolation guided by phased-array intracardiac echocardiography (ICE) as an alternative approach, and to present initial results. METHODS: Patients with symptomatic AF were included. The antra (the larger circumferential area around the PVs) were isolated guided by ICE. ICE was also used to titrate the ablation energy. RESULTS: 38 patients (3 with persistent AF) were included. Of the 35 patients with paroxysmal AF, 24 are without recurrences, and in six the incidence of paroxysms was significantly reduced after one procedure and a mean follow-up of 201 days. No major complications occurred. CONCLUSION: Pulmonary vein antrum isolation guided by ICE is a promising technique in AF ablation and has the potential to avoid severe complications.

Unusual form of AV nodal Wenckebach block.

A 73-year-old man had a fast atrioventricular (AV) nodal pathway accidentally ablated 4 years before, while attempting to ablate a septally located concealed accessory pathway (AP). After initiation of treatment with beta-blockers, because of systemic arterial hypertension, the patient presented to the emergency room complaining of a markedly diminished exercise tolerance. The 12 lead ECG showed an interesting AV nodal Wenckebach sequence, interrupted by P waves retrogradely conducted through the AP. The mechanisms explaining the ECG are discussed.

Magnetic resonance imaging follow-up study of bone bruises associated with anterior cruciate ligament ruptures.

PURPOSE: The purpose of this study was to perform a magnetic resonance imaging (MRI) follow-up study of bone bruises in a group of patients with acute anterior cruciate ligament (ACL) ruptures that were reconstructed and followed-up for a minimum of 2 years. TYPE OF STUDY: Cohort study. METHODS: The study group included 21 patients with a mean age of 31 years whose initial MRI scans showed associated bone bruises. Patients were included if they had an acute isolated ACL tear, no documentation of an episode of repeated injury to the affected knee during the follow-up period, and no evidence of cartilaginous injury at the time of arthroscopy. All patients had preoperative MRI scans and underwent arthroscopic ACL reconstruction using a bone-patellar tendon autograft an average of 2 months after injury. The preoperative MRI scans were analyzed using a 3-level grading system based on the appearance and location of bone bruises. A second MRI of the knee was obtained from 24 to 64 months postoperatively (average 34 months). The presence of resolution of bone bruises was determined and correlation with clinical scoring established. RESULTS: This study showed resolution of all type I lesions and 91% of type II lesions (10 of 11). In all type III lesions, an articular cartilage thinning and depression was observed after 2 years of follow-up. In 15 patients (71%), MRI showed that the bone bruises had resolved without apparent sequelae. In the remaining 6 patients (29%), sequelae of the osteochondral lesion were evident on MRI. CONCLUSIONS: According to our clinical data, there was no correlation between scores obtained from patients with resolved lesions against those with osteochondral sequelae. Although long-term clinical implications of these findings are uncertain, a severe occult osteochondral lesion sustained at the time of ACL rupture seems to be persistent on MRI even after a successful reconstruction.

Magnetic resonance imaging evaluation and arthroscopic resection of localized pigmented villonodular synovitis of the knee.

Diagnosis of localized pigmented villonodular synovitis is clinically difficult, and plain radiographs are usually normal. This article presents five patients with localized pigmented villonodular synovitis of the knee. Symptoms suggested a meniscal lesion in three patients and a loose body in two. Magnetic resonance imaging performed prior to arthroscopic resection revealed a preoperative diagnosis of a tumor in all five patients. Magnetic resonance imaging is a valuable clinical tool for the assessment of intra-articular soft-tissue tumors of the knee that may otherwise be misdiagnosed.

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.

Posibles lesiones osteocondrales asociadas con lesión del ligamento cruzado anterior: evaluación clínica y con resonancia magnética a los 34 meses / Potential osteochondral lesions associated with anterior cruciate ligament rupture: clinical and MRI evaluation after 34 months

Las lesiones osteocondrales (OC) no reveladas por los estudios radiográficos convencionales (contusiones óseas) han sido descritas mediante resonancia magnética (RM) en un alto porcentaje de los pacientes con lesión aguda del ligamento cruzado anterior (LCA). El objetivo de este estudio prospectivo es el de analizar a un grupo de pacientes con rotura del LCA y lesión OC asociada diagnosticada por RM inicial, evaluándolos en forma clínica y con una segunda RM luego de 2 años de la reconstrucción del LCA. Las lesiones OC fueron clasificadas en las RM pre y posoperatorias en 3 grados, según el aspecto de las imágenes y su relación espacial con la superficie articular: grado I (hemorragia difusa intramedular sin contig³idad con el hueso subcondral), grado II (hemorragia contigua al hueso subcondral) y grado III (depresión o solución de continuidad del contorno de la superficie articular). Fueron evaluados 21 pacientes que presentaban lesiones OC en las RM preoperatorias. Quince (71 por ciento) presentaban resolución de la contusión ósea sin secuela evidente en la RM de control. Los 6 pacientes restantes (29 por ciento) presentaban una secuela de la lesión OC que consistía en disminución del grosor del cartílago articular, depresión de la cortical o defecto osteocondral. De acuerdo con nuestros resultados, las lesiones grados I y II tenderían hacia una resolución espontánea en un alto porcentaje de los casos, por esta razón, en la mayoría de los casos no se debería actuar sobre la lesión condral ni alterarse los protocolos de rehabilitación. Por el contrario, en las lesiones grado III se observa secuela en la RM, en estos casos es factible considerar la conveniencia de un tratamiento preventivo

Posibles lesiones osteocondrales asociadas con lesión del ligamento cruzado anterior: evaluación clínica y con resonancia magnética a los 34 meses / Potential osteochondral lesions associated with anterior cruciate ligament rupture: clinical and MRI evaluation after 34 months

Las lesiones osteocondrales (OC) no reveladas por los estudios radiográficos convencionales (contusiones óseas) han sido descritas mediante resonancia magnética (RM) en un alto porcentaje de los pacientes con lesión aguda del ligamento cruzado anterior (LCA). El objetivo de este estudio prospectivo es el de analizar a un grupo de pacientes con rotura del LCA y lesión OC asociada diagnosticada por RM inicial, evaluándolos en forma clínica y con una segunda RM luego de 2 años de la reconstrucción del LCA. Las lesiones OC fueron clasificadas en las RM pre y posoperatorias en 3 grados, según el aspecto de las imágenes y su relación espacial con la superficie articular: grado I (hemorragia difusa intramedular sin contigüidad con el hueso subcondral), grado II (hemorragia contigua al hueso subcondral) y grado III (depresión o solución de continuidad del contorno de la superficie articular). Fueron evaluados 21 pacientes que presentaban lesiones OC en las RM preoperatorias. Quince (71 por ciento) presentaban resolución de la contusión ósea sin secuela evidente en la RM de control. Los 6 pacientes restantes (29 por ciento) presentaban una secuela de la lesión OC que consistía en disminución del grosor del cartílago articular, depresión de la cortical o defecto osteocondral. De acuerdo con nuestros resultados, las lesiones grados I y II tenderían hacia una resolución espontánea en un alto porcentaje de los casos, por esta razón, en la mayoría de los casos no se debería actuar sobre la lesión condral ni alterarse los protocolos de rehabilitación. Por el contrario, en las lesiones grado III se observa secuela en la RM, en estos casos es factible considerar la conveniencia de un tratamiento preventivo

Osteonecrosis of the knee following arthroscopic meniscectomy in patients over 50-years old.

We reviewed eight patients over 50-years old, with an initial diagnosis of medial meniscal tear confirmed with magnetic resonance imaging (MRI) and with no evidence of osteonecrosis. After arthroscopic meniscectomy, all patients had recurrent aggravated knee pain and reevaluation with MRI showed images compatible with osteonecrosis. The average age was 65 years (range 54 to 75 years). The mean time from MRI to surgery was 8 weeks (range 1 to 28 weeks). In five patients a total meniscectomy, and in three a partial meniscectomy with recontouring of the meniscus were performed. Surgical treatment was initially successful, but all eight patients returned to our office with recurrent aggravated pain in the treated knee. Reevaluation with MRI, at an average of 18 weeks postoperatively, found abnormalities at the medial condyle consistent with osteonecrosis. The purpose of this study is to report a potentially serious outcome after arthroscopic meniscectomy in patients over 50-years old.