Secondary aneurysmal bone cyst of the patella

Aneurysmal bone cyst accounts for 1% of primary bone tumors and is one of the benign tumor-like lesions. Patellar involvement is quite rare. Its development on the basis of any previous lesion such as chondroblastoma is called secondary aneurysmal bone cyst. A 26-year-old male patient presented with right knee pain of three-year history. Physical examination showed a firm, immobile swelling at the anterior aspect of the right knee, without increase in temperature or redness of the skin. There was no pain on palpation and joint range of motion was normal. Radiological studies were suggestive of an aneurysmal bone cyst. At surgery, the cystic lesion was removed via curettage and the residual cavity was filled with an autogenous bone graft taken from the iliac wing. The histopathologic diagnosis was secondary aneurysmal bone cyst in association with chondroblastoma. During a 1.5-year follow-up, the patient had no complaint and no recurrence was observed.     

Intrapelvic cyst formation after hip arthroplasty with a carbon fibre-reinforced polyethylene socket

Carbon fibre-reinforced polyethylene cups were inserted in total hip arthroplasties for both hips of a male patient. Ten years after the arthroplasty of the right hip, an intrapelvic cyst was observed. The cyst was connected to the inner acetabular wall. The endoprosthetic cup showed gross loosening with a marked osteolysis of the acetabulum. Revision arthroplasty with allograft bone and an uncemented endoprosthesis was successfully performed. The fibrotic tissue at the bone-cement interface showed numerous histiocytic cells with cytoplasmic infiltrates of carbon and polyethylene particles. The left hip was also later revised for loosening, but no cyst formation was observed on that side.     

Giant-cell tumor of the patella with lung metastases: a case report

Giant-cell tumors are an infrequent clinical, radiological, and pathological entity observed in 5% of primary bone tumors. They generally occur at the epiphysis of long bones, particularly in the knee area but patellar localization seems very rare. Despite their perfectly benign histological aspect, giant-cell tumors may be aggressive, leading to local recurrence or even distant metastasis to the lung. We report a case of benign giant-cell tumor of the patella with lung metastasis observed in a 23-year-old woman. The aggressive radiological image was suggestive of chondrosarcoma. Histologically the differential diagnosis with chondroblastoma was difficult. The tumor and lung metastasis were treated by surgical resection. Four years later there has been no recurrence. We present the anatomic and clinical aspects of giant-cell tumor of the bone together with the diagnostic approach and the clinical course.     

Total Calcanectomy and Bilateral Iliac Bone Autograft Reconstruction for the Treatment of Calcaneal Chondroblastoma Involving a Secondary Aneurysmal Bone Cyst: A Case Report and Literature Review

Chondroblastoma is a rare, benign, cartilaginous-derived tumor accounting for ∼1% to 2% of all primary bone tumors and almost 9% of all benign bone tumors. In this case report, we describe a patient with chondroblastoma and a secondary aneurysmal bone cyst, with the adjacent talus being mildly affected. The initial diagnosis was giant cell tumor and was then confirmed after computed tomography–assisted biopsy. We performed a total calcanectomy via bilateral structural iliac bone autografting to relieve pain and reconstruct the loadbearing function because of the presence of extensive lesions. The patient was pain free and expressed satisfaction with postsurgical dorsiflexion and plantarflexion function at the 60-month follow-up visit. Radiographic images showed that the autografted iliac bone was completely healed, with no evidence of local recurrence.     

Chondroblastoma with secondary aneurysmal bone cyst of the hamate: case report

Chondroblastoma of the carpals is rare, can mimic other benign bone tumors, and presents a diagnostic challenge. There have been few cases of benign tumors involving the hamate, with only one reported case of chondroblastoma, which was treated with complete hamate excision. We present a case of chondroblastoma with secondary aneurysmal bone cyst of the hamate treated with curettage, high-speed burring, phenol, and autogenous iliac crest bone grafting. At the time of the most recent radiographic follow-up, there was full graft incorporation, preserved hamate morphology, and no evidence of recurrence.     

Tumors of the footbones- a report from the Hamburg Bone Tumor Registry

Aim of the present study was a systematic examination of the tumors of the foot registered in the Hamburg Bone Tumor Registry regarding age, sex, location, diagnosis and morphological characteristics. The registry files and histological specimens of 367 tumors and tumor-like lesions of the foot were reviewed. Males were more frequently affected (ratio 4 : 3). Some 20.4 % of all mass forming tumors were malignant. Cartilage tumors (146 cases), cystic (132 cases) and osteoblastic lesions (33 cases) were most common. Several tumors showed a strong predilection for certain parts of the foot. In the calcaneus a solitary bone cyst was the most common lesion. Lesions in the talus and metatarsals with a similar morphology mostly represented intraosseous ganglion cysts. Other tumors in the calcaneus were mainly cartilaginous. Besides chondroblastoma, chondrosarcoma was regularly diagnosed. Chondroma was extremely rare at this site. Contrary to that chondroma was regularly found at the metatarsal and phalangeal bones, it was 4 times more common than chondrosarcoma. An even distribution showed aneurysmal bone cysts and osteoidosteoma. Very rare lesions were fibrous dysplasia, eosinophilic granuloma and intraosseous lipoma. The knowledge of the distribution of tumors in the foot is important for an exact differential diagnosis and thereby for biopsy planning, diagnosis and therapy.     

Chondromyxoid fibroma: a rare tumor with an unusual location

Chondromyxoid fibroma constitutes a rare benign tumor of the bones, which has a potential of regional enlargement towards the local tissues. An adult male patient at the age of 28 suffered a fracture of the lateral malleolus due to an eccentric, lytic, lobular lesion in the epiphysis, during a basketball match. The differential diagnosis included the chondroblastoma, the aneurysmal cyst and the chondrosarcoma. After the removal of the tumor with curettage, both with curette and with a high-speed burr, osseous cement was placed in the cavity of the lesion. The biopsy of the tumor confirmed the diagnosis of the chondromyxoid fibroma. This is the first unusual location of the tumor in the national bibliography. The patient after 5 years post-operatively does not show either clinical or radiological signs of regional recurrence of the tumor.     

Chondroblastoma with associated aneurysmal bone cyst of the cuboid

The authors describe a young adult patient with a chondroblastoma and associated aneurysmal bone cyst of the cuboid. Although chondroblastoma has been reported to occur in tarsal bones, the cuboid is a very rare location. The association of chondroblastoma with an aneurysmal bone cyst in long bones has been well documented. However, this association in the cuboid has not been reported in the English literature. A 20-year-old man with a 4-month history of foot pain localized to the lateral border of the foot and ankle presented with an expansile lesion in the cuboid bone with a nondisplaced pathologic fracture. A computed tomography scan showed an expansile lesion with discontinuity of the cortex, and magnetic resonance imaging showed marrow replacement within the cuboid with surrounding periosteal edema. An open biopsy was performed, followed by curettage and cementation of the lesion. The histology showed a chondroblastoma with an associated aneurysmal bone cyst of the cuboid.     

Surgical treatment of primary tumors of the sacrum

Twenty-two patients with primary tumors of the sacrum were surgically treated between 1983 and 1997. Seventeen male and 5 female patients were followed up for a mean of 53.6 months (range 12-203 months). The histopathologic diagnoses were giant cell tumor (GCT) in 7 patients, chordoma in 4 patients, aneurysmal bone tumor in 3 patients, chondrosarcoma in 2 patients, osteoblastoma in 2 patients, synovial sarcoma in 2 patients, Ewing's sarcoma in 1 patient, and simple bone cyst in 1 patient. Currettage and thermo- or chemocauterization was applied to 8 patients, a subtotal sacrectomy was done in 11 patients, and total sacrectomy and lumbopelvic stabilization was done in 3 patients. The surgical margins were wide in all patients with GCT. The surgical margins were wide in 3 patients and wide contaminated in 1 patient with chordoma. The 2 patients with chondrosarcoma had high sacral lesions and were managed with total sacrectomy and lumbopelvic fixation. The surgical margin was wide in 1 patient and wide contaminated in the other, who relapsed locally and systemically in the 30th postoperative month. Three patients with aggressive aneurysmal bone cyst and 1 patient with simple bone cyst were managed by curettage and thorough debridement. One patient with low sacral Ewing sarcoma was managed by subtotal sacrectomy with wide margins. The two osteoblastomas were localized to the posterior elements of the sacrum. None of the patients relapsed. Most of the tumors of the sacrum are benign aggressive lesions or low grade malignancies. Intralesional resections in the form of curettage, with the addition of chemo- or thermocauterization, provide a complete cure for benign lesions. In contrast, wide resections are necessary for complete disease control in radio- and chemoresistant malignancies. Nerve root dissection should be performed in order to achieve wide margins.     

Knorpelbildende Tumoren

Primary cartilage-forming tumors of the bone are a large group among the rare bone tumors. The clinical and radiographic findings of the different entities show similar findings. Bone biopsy is still the most relevant examination in the final diagnosis of the lesion. The requirements for a correct biopsy and the main features of the macroscopic and histologic findings of cartilage tumors are presented from the viewpoint of the pathologist. Differentiation between benign enchondroma and grade I chondrosarcoma requires close interdisciplinary cooperation to avoid over-treatment and relapse. Rare low-grade malignant cartilage tumors such as clear-cell chondrosarcoma need to be diagnosed in specialized centres to arrive at the correct therapy. The morphologic features of mesenchymal chondrosarcoma, clear-cell chondrosarcoma and secondary chondrosarcoma in osteochondroma are demonstrated. The aim is to correlate the morphologic and radiographic features. The same applies to benign entities such as osteochondroma, chondroblastoma and chondromyxoid fibroma.     

Cartilage tumors. Classification, conditions for biopsy and histologic characteristics

Primary cartilage-forming tumors of the bone are a large group among the rare bone tumors. The clinical and radiographic findings of the different entities show similar findings. Bone biopsy is still the most relevant examination in the final diagnosis of the lesion. The requirements for a correct biopsy and the main features of the macroscopic and histologic findings of cartilage tumors are presented from the viewpoint of the pathologist. Differentiation between benign enchondroma and grade I chondrosarcoma requires close interdisciplinary cooperation to avoid over-treatment and relapse. Rare low-grade malignant cartilage tumors such as clear-cell chondrosarcoma need to be diagnosed in specialized centres to arrive at the correct therapy. The morphologic features of mesenchymal chondrosarcoma, clear-cell chondrosarcoma and secondary chondrosarcoma in osteochondroma are demonstrated. The aim is to correlate the morphologic and radiographic features. The same applies to benign entities such as osteochondroma, chondroblastoma and chondromyxoid fibroma.     

髌骨软骨母细胞瘤诊断及治疗进展

髌骨软骨母细胞瘤（chondroblastoma of patella）是一种发生在髌骨的少见的良性骨肿瘤,相对于骨巨细胞瘤,其在髌骨的发病率更低。同时,该肿瘤临床表现多样,可表现出各种复杂的影像学特征。因此,即使专业的骨科医生对其认识仍有可能不足。髌骨软骨母细胞瘤在X线片、CT及MRI上与骨巨细胞瘤等肿瘤的鉴别是近年来的研究焦点之一。有时它与动脉瘤样骨囊肿可合并存在,这就对进行准确的病理及影像学诊断提出了更进一步的挑战。在治疗上,病灶刮除植骨术是目前主流的手术方法,但对于是否需要在术前进行活检仍存在争议。此外,新的射频消融等技术用于治疗的前景到底如何仍未可知。     

Chondroblastoma: a rare cause of femoral neck fracture in a teenager

Chondroblastomas usually present in the epiphyseal region of bones in skeletally immature patients. These uncommon, benign tumors are usually treated with curettage and use of a bone-void filler. Here we report a case of a hip fracture secondary to an underlying chondroblastoma in a 19-year-old woman. Open biopsy with intraoperative frozen section pointed toward a diagnosis of chondroblastoma. Extended curettage was performed, followed by cryotherapy with a liquid nitrogen gun and filling of the defect with calcium phosphate bone substitute. The femoral neck fracture was stabilized with a sliding hip screw construct. The patient progressed well and continued to regain functional status. A final pathology report confirmed the lesion to be a chondroblastoma. Clinicians should have heightened awareness of a pathologic lesion in a young person presenting with a femoral neck fracture and should consider the uncommon differential diagnosis that the lesion is located in the greater trochanter apophysis.     

Aneurysmal bone cyst in the first rib

Aneurysmal bone cyst is a benign tumor of the skeletal system that rarely occurs in ribs. We report two cases of aneurysmal bone cyst in the first rib. The first patient was a 21-year-old woman with an aneurysmal bone cyst in the left first rib that was resected with an L incision. The second patient was a 42-year-old man with an aneurysmal bone cyst in the right first rib that was resected with a posterolateral incision but recurred 1 year later. An en bloc resection was performed, without recurrence to date. We also review this disease with emphasis on the etiology, clinicopathology, and treatment approaches.     

髋臼周围肿瘤的切除与重建

目的 探讨髋臼周围肿瘤切除与重建的方式及合并症。方法 回顾分析1997年7月至2003年7月髋臼部位原发肿瘤患者行肿瘤切除重建手术的临床资料。3l例患者中,男性19例,女性12例,年龄12～78岁,平均年龄37岁。其中,软骨肉瘤12例、尤文瘤1例、骨肉瘤3例、淋巴瘤1例、癌肉瘤1例、恶性纤维组织细胞瘤1例、骨髓瘤2例、骨巨细胞瘤9例、动脉瘤样骨囊肿1例。2l例患者行髋臼切除、骨盆重建,其中人工半骨盆8例、马鞍式关节7例、灭活再植 人工髋关节置换6例。10例患者行肿瘤刮除 骨水泥填充 人工髋关节置换。结果 21例行Ⅱ区肿瘤切除、髋臼重建的患者中,5例出现局部复发,其中3例为行半骨盆灭活再植的患者。3例骨肉瘤中2例死亡;12例软骨肉瘤患者中,随访9人,6例无瘤生存。术后2个月后,21例患者能够正常坐、扶单拐行走。结论 髋臼区域的肿瘤切除后可行异体或人工半骨盆移植进行修复,或将瘤段骨壳灭活再植进行重建。髋臼周围肿瘤切除重建的过程中应注意：(1)广泛切除肿瘤;(2)熟悉各种髋臼重建方法的优缺点,防止合并症的发生;(3)髋臼重建后的稳定性较差,应注意站立时在健侧拄一手杖,保护再造髋关节;(4)预防皮缘坏死及伤口感染,骨盆肿瘤切除容易发生伤口问题。     

Long-term results of salvage procedures following intrapelvic migration of loosened total hip arthroplasties

INTRODUCTION: Intrapelvic migrations of loosened total hip arthroplasties are rare. Primary objective of revision arthroplasty in these cases is the reconstruction of acetabular defects for example by acetabular reinforcement rings. Presenting 3 cases the possibilities and long-term results of Girdlestone situations or arthrodesis of the hip following intrapelvic migration of a total hip arthroplasty are described. PATIENTS AND METHODS: A Girdlestone procedure was performed in a 62-year-old female patient due to intrapelvic migration of a threaded cup and development of a false aneurysm of the iliac artery. 15 years later the patient was out of any complaints. In another patient an arthrodesis of the hip due to destruction of the acetabulum and central migration of a hemiprosthesis was performed. 15 years later, too, this patient was out of any complaints. In a third patient with a contralateral preexisting Girdlestone hip an arthrodesis of the hip due to excessive loosening and severe acetabular defects of a cemented total hip arthroplasty was performed on the other side. 13 years later both hips were stiff, nevertheless the patient was satisfied. CONCLUSION: Presenting these cases we come to the conclusion that even now a Girdlestone operation or an arthrodesis of the hip should be taken into account if reconstruction of acetabular defects is no more feasible. The long-term results are satisfactory.     

An Intraosseous Lipoma of the Calcaneus: A Case Report

Intraosseous lipomas are one of the rarest bone tumors found in the body. The incidence has been reported to be <0.1% of all primary bone tumors. The differential diagnoses of an intraosseous lipoma in the calcaneus include plantar fasciitis, retrocalcaneal bursitis, gout, stress fracture, unicameral bone cyst, aneurysmal bone cyst, osteoblastoma, enchondroma, chondromyxoid fibroma, nonossifying fibroma, giant cell tumor, chondroblastoma, fibrous dysplasia, and chondrosarcoma. It has been reported that 60% to 70% of patients with an intraosseous lipoma present with symptoms. This article describes a case of a pathologic fracture secondary to a large intraosseous lipoma, the surgical treatments, and the subsequent resolution of symptoms. The purpose of our report was 3-fold: (1) to increase awareness of intraosseous lipomas and their potential to cause pathologic fractures in the calcaneus; (2) to suggest a possible treatment protocol for intraosseous lipomas in the calcaneus; and (3) to describe a rare case of an intraosseous lipoma of the calcaneus not located exclusively in the neutral triangle.     

Malformation of the acetabular fossa as a cause of intrapelvic injury in total hip arthroplasty: a report of 2 cases

We report 2 cases of bone defects of the acetabulum. The first case was a patient who underwent a total hip arthroplasty. An intraoperative bleeding occurred because of an injury of an intrapelvic artery. Preoperative radiographs did not show this bone defect. A similar abnormality of the acetabulum was found in a series of 30 pelves that were dissected for a cadaver study. In this case, the bone defect was located in the center of the right acetabulum.     

Early management of pathological fractures in children

The management of pathological fractures in children remains controversial. The indications for surgical treatment are unclear and the need for histological diagnosis before or after definitive treatment is not clearly defined. We reviewed retrospectively the records of all patients under the age of 16 years who presented over the past 7 years with a fracture as the first manifestation of bone pathology. There were 23 patients (16 boys and 7 girls) of an average age of 12 years and 2 months (range 4.1-15.8 years). There were nine cases of fracture through a simple bone cyst, five cases of fibrous dysplasia, two giant cell tumours, three aneurysmal bone cysts, one chondroblastoma, and three cases of Ewings sarcoma. After review of our cases we propose a simple algorithm for the safe early management and assessment of paediatric pathological fractures. We recommend that primary fixation of pathological fractures should be avoided until histological diagnosis is obtained. Most lesions should eventually be biopsied. However, if radiographic appearances are reassuringly benign, biopsy can be delayed until conservative fracture management is completed. Definitive treatment of benign lesions with protective intra medullary nailing or curettage and grafting can follow frozen section under the same anaesthetic.