Case report 337: Cystic chondroblastoma of calcaneus

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.

Fluid-fluid Levels in Musculoskeletal Tumor Imaging

Fluid-fluid levels result from the separation of two fluids of differing densities within a cavernous space with the boundary between the two layers running in a horizontal plane at 90 degrees to the direction of gravity. Magnetic resonance imaging is the most sensitive imaging modality to identify fluid-fluid levels. Although the most common bone lesions containing fluid-fluid levels are aneurysmal bone cyst and telangiectatic osteosarcoma, fluid-fluid levels can be observed in a wide variety of bone and soft tissue lesions. Therefore, fluid-fluid levels cannot be considered diagnostic of any particular type of tumor and the diagnosis should be made on the basis of other clinical, radiological and pathological findings. This article summarizes the pathophysiology and imaging characteristics of fluid-fluid levels and discusses the differential diagnosis of tumors with this imaging sign.

Chondroblastoma of the Foot: 40 Cases From a Single Institution

Chondroblastoma (CB) of the foot is a rare lesion. The purpose of this report was to report a large series from a single institution to analyze clinical, radiographic, and histologic characteristics; treatment; and local recurrence. We present 40 patients (30 males, 10 females; mean age 25 years) diagnosed and treated for CB of the foot from 1975 to 2012. The mean follow-up visit was 55 months (range 7 months to 11 years). Clinical presentation, histology, imaging, surgical treatment, and local recurrence were evaluated. Males were more affected than females. The main symptom was pain (100%) accompanied by swelling (35%), with median duration of 12 months. The talus (50%) and calcaneus (37.5%) were the most affected bones. All patients underwent surgery: curettage (10 cases), curettage and bone graft (15 cases), curettage and cement (13 cases), wide resection (1 case), and Chopart amputation (1 case). Ten patients (25%) had secondary aneurysmal bone cyst. One patient had local recurrence after surgery. In conclusion, patients with CB of the foot are usually older than 20 years, and males are most affected. The hindfoot is the most affected area. Surgical treatment is required, and intralesional curettage and packing with cement or graft is curative in most cases. Local recurrence in foot is lower than in other locations.

Aneurysmal Bone Cyst: An Uncommon Secondary Event in Calcaneal Chondroblastoma

Chondroblastoma is an uncommon benign bone tumour, involvement of epiphysis of long bones is typical. Chondroblastoma of the calcaneum is uncommon and its association with secondary aneurysmal bone cyst is even rarer. Only two cases of calcaneal chondroblastoma associated with secondary aneurysmal bone cyst have been reported till date. A 22-year-old male presented to the department of orthopaedics with complains of pain and swelling in the left heel since the last 10 months. On clinico-radiological grounds differentials considered were giant cell tumour of bone and aneurysmal bone cyst. In view of the histopathological findings of bone curettage and results of special stain and immunohistochemical marker, final diagnosis of chondroblastoma with secondary aneurysmal bone cyst, left calcaneum was rendered. Although rare, chondroblastoma should always be considered in osteolytic lesions of calcaneum. The identification of secondary aneurysmal bone cyst component is important as it has higher chances of recurrence than usual chondroblastoma.

Calcaneal chondroblastoma with pathologic fracture and recurrence

Chondroblastomas account for <2% of all bone tumors. The calcaneus is the fifth most common location of occurrence. Males in their second decade of life are most often affected, presenting with an insidious onset of localized pain, swelling, and tenderness. The finding of associated pathologic fracture has been rare. Imaging studies can aid in the formulation of the differential diagnosis and surgical plan. The definitive diagnosis requires histologic examination. Curettage and bone grafting is curative in >80% of cases. Local recurrence rates of ≤38% have been reported, most often because of inadequate resection, and have been associated with malignant conversion and metastasis. Adjuvant therapies can help minimize the incidence of local recurrence. Long-term follow-up examinations are recommended, given the protracted interval that can exist between recurrence and the potential for malignant conversion and metastasis. We present the case of a young, healthy, active male with a calcaneal chondroblastoma and associated pathologic fracture whose initial treatment consisted of curettage, hydrogen peroxide lavage, and allogeneic bone grafting. Recurrence developed at 15 months postoperatively and was treated with repeat curettage, high-speed burring, and reconstruction with steel Steinman pins and polymethylmethacrylate, resulting in no pain or recurrence at the 5-month follow-up point.

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.

Calcaneal chondroblastoma with secondary aneurysmal bone cyst: a case report

We present a case of destructive chondroblastoma associated with secondary aneurysmal bone cyst involving the left calcaneus. Because of the extensive destruction of the calcaneus, total calcanectomy was the treatment of choice.

Fluid-fluid levels in bone neoplasms: variation of T1-weighted signal intensity of the superior to inferior layers--diagnostic significance on magnetic resonance imaging

The diagnostic relevance of the relative T1-weighted (T1W) and T2-weighted (T2W)/short tau inversion recovery (STIR) MRI signal intensity characteristics of the superior to inferior fluid layers within fluid-fluid levels (FFLs) found in bone tumours was investigated. A retrospective analysis was performed of MRI studies of 2,568 patients presenting with a suspected bone tumour over an 8-year period. Final diagnosis was made by biopsy/surgical resection or characteristic imaging/clinical findings. Subjects were divided by the absence/presence of FFLs and benign/malignant histology. Cases with FFLs were sub-categorised by the relative signal intensity of the superior/inferior layer as high/low or low/high on T1W and T2W/STIR sequences. Out of the total of 2,568 cases, 214 (8.3%, CI 7.3-9.5%) had FFLs and 2,354 (91.7%, CI 90.5-92.7%) had no FFLs. All 214 cases with FFLs had T2W/STIR sequences available, all demonstrating high/low signal intensity characteristics; 135/214 (63.1%, CI 56.2-69.6%) were benign and 79/214 (36.9%, CI 30.4-43.8%) were malignant. Out of the 214 patients, 151 had T1W sequences performed; 52 showed high/low signal intensity, of which 30 (57.7%, CI 34.2-71.3%) were benign and 22 (42.3%, CI 28.7-56.8%) were malignant (P = 0.06 compared with no FFL group); 50 showed low/high signal intensity, of which 40 (80%, CI 66.3-90.0%) were benign and ten (20%, CI 10.0-33.7%) were malignant (P = 0.0000, compared with the no FFL group). The low/high and high/low groups had a significantly greater proportion of benign and malignant lesions, respectively (P = 0.015). In conclusion, all FFLs showed high/low signal intensity characteristics on T2W/STIR sequences. Low/high signal on T1W was significantly associated with benign disease. Malignancy may occur slightly more frequently with high/low signal on T1W.

Treatment of chondroblastoma of the calcaneus with a secondary aneurysmal bone cyst using endoscopic curettage without bone grafting

Chondroblastoma is a relatively rare benign bone tumor. Approximately 7% of chondroblastomas occur in the calcaneus, and 17% of chondroblastoma associated with cystic lesions. We report a case of a chondroblastoma in the calcaneus with a secondary aneurysmal bone cyst treated successfully by endoscopic curettage without bone grafting. New bone formation is facilitated by minimal damage to the bone and soft tissue. The cosmetic results of this procedure are good. Two years later, the patient is asymptomatic with no radiographic evidence of recurrence. Endoscopic curettage without bone grafting is a promising new treatment for chondroblastoma.

Chondroblastoma of the foot

A total of 322 cases of chondroblastoma were referred to the Armed Forces Institute of Pathology between 1960 and 1990. Ten additional cases of chondroblastoma were treated at Walter Reed Army Medical Center between 1985 and 1993. Forty-two of these involved the foot, two of which were treated at Walter Reed Army Medical Center. Patients with chondroblastoma of the foot were male in 35 (81%) cases, with a mean age of 25.5 years, which was significantly different from the mean age of 17.3 years in patients with chondroblastoma of the long bones (P < 0.0001). Chondroblastoma of the foot is most commonly found in the posterior subchondral areas of the talus and calcaneus as well as in the calcaneal apophysis. Radiographically, the lesion was associated with an articular surface or apophyseal area in all cases and appeared radiolucent, with little to no matrix production. The margins were generally well defined. Cystic features were noted grossly and histologically in 24 (57%) specimens, a feature seen in only 21% of all chondroblastomas overall. Treatment consists of thorough curetting and bone grafting with good oncologic and functional results.

Chondroblastoma of the talus

Chondroblastomas are rare cartilaginous tumors that are found in the foot or ankle. They are usually located in portions of the humerus, tibia, or femur, and comprise approximately 1 to 3% of all osseous tumors. This is a unique case report of a chondroblastoma involving the talus of a young individual.

The incidence and significance of fluid-fluid levels on computed tomography of osseous lesions

The demonstration of a fluid-fluid level (FFL) within an osseous lesion on computed tomography (CT) has been reported as suggestive of an aneurysmal bone cyst (ABC) although FFLS have also been rarely found in association with other lesions. This study was conducted to determine the frequency of FFLS on CT in a group of ABCs and a series of patients presenting to a major tertiary referral centre for the treatment of bone tumours. An FFL was present on CT in 21 (84%) of the 25 ABCs and in 17 was multiple. FFLs are typical of the mid ("blow-out") or late phase of development of an ABC and not the incipient ("permeative") stage or where the internal architecture of the tumour has been disrupted by biopsy or previous surgery. In a 3-year period, 16 ABCs were found in 491 bone lesions referred to a bone tumour treatment centre. CT of the ABCs revealed FFLs in 14 (87.5%) cases. Within the same period, 728 CTs of these and other bone lesions were performed and FFLs were identified in two further cases: a massive telangiectatic osteosarcoma and a conventional osteosarcoma following chemotherapy. The diagnostic significance of an FFL on CT for ABC is: sensitivity = 87.5%, specificity = 99.7%, positive predictive value = 87.5%, negative predictive value = 99.7%, accuracy = 99.4%. An FFL within a bone lesion on CT remains strongly suggestive of an ABC although the radiologist should be wary of a rare telangiectatic osteosarcoma.

Fluid-fluid levels in giant cell tumors of bone: report of two cases

Fluid-fluid levels have been described in association with aneurysmal bone cysts, telangiectatic osteosarcoma, and a chondroblastoma. We report two cases of giant cell tumors of bone with fluid-fluid levels identified by computed tomography and, in one case, by magnetic resonance imaging. This finding has not previously been associated with giant cell tumors. The radiographic features of the fluid-fluid levels cannot be distinguished from those reported in other osseous neoplasms.