Intraosseous ganglion

Neoplastic and Non-neoplastic Bone Lesions of the Knee

Numerous anatomical variants are described around the knee, many of which look like bony lesions, so it is important to know them to avoid unnecessary complementary tests and inadequate management. Likewise, several alterations in relation to normal development can also simulate bone lesions.However, numerous pathologic processes frequently affect the knee, including traumatic, inflammatory, infectious, and tumor pathology. Many of these entities show typical radiologic features that facilitate their diagnosis. In other cases, a correct differential diagnosis is necessary for proper clinical management.Despite the availability of increasingly advanced imaging techniques, plain radiography is still the technique of choice in the initial study of many of these pathologies. This article reviews the radiologic characteristics of tumor and nontumor lesions that may appear around the knee to make a correct diagnosis and avoid unnecessary complementary radiologic examinations and inadequate clinical management.

Giant intraosseous ganglion of the fibula: multimodality imaging

Intraosseous ganglia around the knee are most commonly located in the proximal tibia and limited to the epiphyseal-metaphyseal region. We report the case of a giant intraosseous ganglion of the fibula. MRI demonstrated the fluid avascular content of the lesion. CT arthrography of the knee demonstrated partial opacification of the lesion through a cortical bone defect. The lesion was treated with curettage and bone grafting. Anatomopathological examination confirmed the medical imaging diagnosis of intraosseous ganglion. This case highlights the value of joint opacification with CT arthrography to demonstrate the communication between the articular cavity and the ganglion.

Carpal bone cysts: MRI, gross pathology, and histology correlation in cadavers

PURPOSE

Intraosseous cysts of carpal bones are frequently observed on routine imaging examinations of the wrist. There is controversy regarding the underlying pathogenesis of these cysts. In this study, we aimed to investigate the magnetic resonance imaging (MRI) appearance of intracarpal bone cysts in correlation with histologic analysis, using cadaveric wrists.

METHODS

Five freshly frozen cadaveric wrist specimens (from three women and two men; mean age at death, 80 years) were studied. Imaging was performed with T1-weighted fast spin-echo, and proton density-weighted fast spin-echo with and without fat-suppression. The existence of cysts was confirmed by comparing MRI and histology findings. Hematoxylin and eosin stain was performed on tissue slices of 3 mm thickness to analyze the structure of cysts and their communication with the joint cavity.

RESULTS

Ten cysts were observed. In all cases, cysts were eccentrically located either in the subchondral bone or beneath the cortex. On histologic examination, there were regions of fat necrosis without inflammation or increased vascularity, surrounded by fibrous walls. There were no giant cells, cholesterol granules, or a true synovial lining. Mucoid change was rare. Fibrous component of cysts varied from small fibrous septa to well-formed walls. Some cysts communicated with the joint cavity. Two cysts were adjacent to ligamentous attachments. Those cysts with fibrous tissue demonstrated variable hypointensity on T2.

CONCLUSION

In contrast to previous reports that described a mucoid composition of intracarpal bone cysts with occasional foamy macrophages, our observations support the concept that these lesions reflect a spectrum of fat necrosis and fibrous changes, without inflammation or hypervascularity. These cysts are typically surrounded by fibrous walls without a true synovial lining.

Solid variant of aneurysmal bone cyst of the hamate

Solid variant of aneurysmal bone cyst is a variant of aneurysmal bone cyst in which the predominant histology is that of the solid material of a cystic aneurysmal bone cyst. In this article, we present a patient with solid variant of aneurysmal bone cyst of the hamate and discuss the differential diagnosis and current treatment for this lesion.

Ganglion cyst of the carpal navicular. A case report and review of the literature

Intraosseous ganglion (IOG) cyst of the scaphoid is an infrequent cause of hand and wrist pain. Intraosseous ganglia located in the scaphoid have rarely been described in the literature. We report the case of a 30-year-old right-handed woman who presented with a more than 24-month history of progressive right-wrist pain. No history of trauma was reported.Conservative treatment with anti-inflammatory medications before referral was unsuccessful. Examination revealed a small palpable mass in the carpal navicular region with no limitation of normal wrist motion. An IOG cyst of the scaphoid was found on standard radiograph and CT-scan of the wrist. Treatment consisted in curettage of the cyst followed by packing of the defect with autologous cancellous bone graft harvested in the distal end of the radial metaphysis. Satisfactory functional recovery was achieved. The clinical, radiographic and therapeutic aspects of this rare condition are discussed by the authors.

Morphology and topography of intraosseous ganglion cysts in the carpus: an anatomic, histopathologic, and magnetic resonance imaging correlation study

PURPOSE

To assess the morphology, topography, frequency, and etiology of intraosseous carpal ganglions.

METHOD

Two hundred and eighty formalin fixed cadaveric wrists (mean age 80.3 +/- 9.7 years, range 40 to 101 years) were radiographed. Fifty specimens suspicious for cyst-like bone lesions underwent magnetic resonance imaging (T1w and proton density-fat-saturated images, 1.5T). Dissection, articular surface assessment, and histological examination were performed. Cystic lesions with adjacent destruction of the hyaline cartilage were classified as degenerative and were excluded.

RESULTS

In 27 of the 50 specimens, 48 ganglion cysts (GC) were found. Prevalence of GC was 9.6%. Of 48 intraosseous carpal GC, 41 (85%) were in a peripheral location; 27/48 (56%) were located at the palmar carpus. GC had a macroscopic and microscopic relationship to the insertion of degenerated ligaments. They developed near longitudinally orientated bone surfaces, which serve as insertion for ligaments and are exposed to tension loading.

CONCLUSIONS

Unlike degenerative cysts, ganglion cysts do not erode the hyaline articular cartilage and almost always have a continuity with the capsular ligaments. Intraosseous carpal ganglion cysts are probably the result of mucoid degeneration of adjacent ligaments.

Flexor tendon ruptures caused by an intraosseous ganglion of the hook of the hamate

A rare case of pathological rupture of the flexor tendons of the small finger caused by an intraosseous ganglion of the hook of the hamate is described.