Giant cell tumor of bone

Giant cell tumor is a common benign bone tumor that possesses specific features including location at the end of long bone, a strong tendency toward local recurrence, and the rare capacity to metastasize to the lungs. Preferred treatment usually consists of extensive curettage and filling of the cavity with bone graft or cement. Debate still exists about the usefulness of local adjuvant treatment. Functional outcome is usually very good.

Vertebroplasty and kyphoplasty: filler materials

Over 700,000 osteoporotic compression fractures occur each year in the United States, twice the number of hip fractures. These vertebral fractures, most of which occur in the elderly, represent significant personal and societal burdens. Percutaneous vertebroplasty (PVP) is a minimally invasive method that involves the percutaneous injection of polymethylmethacrylate (PMMA) into a collapsed vertebral body to stabilize the vertebra. Kyphoplasty is an advanced minimally invasive technique with a number of potential advantages over PVP, including lower risk of cement extravasation and better restoration of vertebral body height and spinal biomechanics. The filling materials used for both these techniques require good biocompatibility, good biomechanical strength and stiffness, and good radiopacity for the fluoroscopy guided procedures. New filler materials (synthetic bone substitutes, e.g., composite resin materials, calcium phosphate or calcium sulfate cements) in addition to new PMMA formulations are now available for clinical use. In this review paper, we will focus on the issues and characteristics of these filler materials as they pertain to vertebral augmentation procedures.

"Occult" osteoporotic vertebral fractures: vertebral body fractures without radiologic collapse

STUDY DESIGN

Retrospective observational study.

OBJECTIVES

We report our experience with patients who presented with osteoporotic vertebral fractures with no visible deformation of vertebral body.

SUMMARY OF BACKGROUND DATA

The diagnosis of osteoporotic vertebral fractures largely relies on the observation of vertebral deformations on plain radiographs, termed vertebral collapses. There are no data on the characteristics, or indeed of the reality, of osteoporotic vertebral fractures with no significant deformation of the vertebral body.

METHODS

We retrospectively analyzed cases that presented with acute back pain with no initial deformation of the vertebral body on plain radiographs, and later proved to be fresh osteoporotic vertebral body fractures. All cases met each of the following criteria: 1) The incriminated vertebra appeared normal on initial radiographs (Genant's Grade 0 deformation). 2) The diagnosis of fresh vertebral body fracture was confirmed by MRI. 3) The diagnosis of osteoporosis was made by the combination of established osteoporosis, ruling out of underlying disease, and follow-up.

RESULTS

We observed 21 fractures in 16 patients (11 female/5 male; mean age, 72 years). Most of these fractures affected the lumbar spine (14 of 21 occurred at L2-L5). Osteoporosis was known beforehand in 9 patients and newly diagnosed in 7 patients. At follow-up, radiographs were obtained for 19 of 21 fractures: in 15 cases, the vertebral fracture developed a vertebral collapse (Genant's Grade > or = 0.5) in a mean of 12.5 weeks (range, 4-24 weeks); in the 4 remaining cases, the vertebra remained normal. All cases had a clinically favorable outcome.

CONCLUSION

Osteoporotic vertebral fractures with no sign of vertebral collapse on initial radiographs do indeed exist. They are analogous to occult stress fractures well known in other skeletal sites. They must not be misdiagnosed as malignant lesions.

Malignant transformation of ameloblastic fibroma to ameloblastic fibrosarcoma: case report and review of the literature

INTRODUCTION

Ameloblastic fibrosarcoma is a rare malignant odontogenic tumour and is regarded as the malignant counterpart of the ameloblastic fibroma. The epithelial component remains benign, but the mesenchymal component becomes malignant. The diagnosis is made by histopathology.

PATIENT

The case of a 26-year-old man who underwent curettage of an ameloblastic fibroma and died of an ameloblastic fibrosarcoma is presented, and the course of malignant transformation is analysed retrospectively.

CONCLUSION

One-third of ameloblastic fibrosarcoma cases seem to have developed from recurrent ameloblastic fibromas. Knowledge of the malignant potential in the mesenchymal spindle cells of ameloblastic fibroma will assist in determining the management of these benign tumours, and may prevent malignant transformation to ameloblastic fibrosarcoma.

The threshold of bone mineral density for vertebral fractures in female patients with primary hyperparathyroidism

BACKGROUND AND OBJECTIVE

Primary hyperparathyroidism (pHPT) is one of the causal diseases that induce secondary osteoporosis. Although patients with pHPT have reduced bone mineral density (BMD) especially at the cortical bone, there have been controversies about risk of fracture. Moreover, no reports have been available about the threshold of BMD for fractures in pHPT patients.

METHODS

BMD values were measured by dual-energy x-ray absorptiometry at lumbar spine, femoral neck and distal one third of radius. Various indices were compared in 116 female pHPT patients and 716 control subjects. Moreover, we analyzed relationship between the cut-off values of BMD and the prevalence of vertebral fractures in pHPT and control subjects.

RESULTS

The prevalence of subjects with vertebral fractures was lower in pHPT patients, compared with that of control subjects. Age and body height were significantly higher and lower in pHPT women with vertebral fractures, respectively. Lumbar spine BMD was significantly lower in pHPT women with vertebral fractures, presumably due to their increased age. There were no differences in femoral neck and radius BMD or in bone metabolic indices between pHPT women with and without vertebral fractures. On the other hand, age-matched BMD was not significantly different between both groups at any measured site. Cut-off values of BMD at lumbar spine and femoral neck were lower in postmenopausal pHPT patients, compared with those of the postmenopausal control group. Moreover, cut-off values of BMD at radius was much lower in postmenopausal pHPT patients, compared with those of the postmenopausal control group (pHPT vs control (g/cm(2)): 0.670 vs 0.706 at lumbar spine; 0.549 vs 0.570 at femoral; 0.394 vs 0.474 at radius). Sensitivity and specificity of vertebral fractures was lower in pHPT patients, compared with those in control group.

CONCLUSIONS

The present cross-sectional study demonstrated that thresholds of BMD for vertebral fractures were lower especially at radial bone in female patients with pHPT, compared with those in the control group.

Balloon kyphoplasty for treatment of sacral insufficiency fractures. Report of three cases

Sacral insufficiency fracture is a painful injury, for which no effective treatment currently exists. The objective of this study was to report on the clinical outcomes and technical aspects of balloon kyphoplasty, which was used in three patients with this injury. Three elderly women with intractable pain from sacral insufficiency fractures were treated with polymethyl methacrylate (PMMA) injections into the sacrum by using a modified balloon kyphoplasty procedure. The visual analog scale pain score improved by four points in each case. Functional status was improved and analgesic medication requirements were decreased in all three patients. There were no complications associated with the procedure. Because of the unique anatomy of the sacrum, it was difficult to monitor instrument placement and PMMA injection by using conventional fluoroscopy. BrainLAB image guidance was used in one case, and was helpful in guiding instrument placement and assuring accurate PMMA deposition at the fracture site. Balloon kyphoplasty may be a treatment alternative in selected patients with sacral insufficiency fractures. BrainLAB image guidance may offer some advantages over conventional fluoroscopy with regard to the monitoring of instrument placement and PMMA injection.

Combination kyphoplasty and spinal radiosurgery: a new treatment paradigm for pathological fractures

OBJECT

Patients with symptomatic pathological compression fractures require a stabilization procedure for mechanical control of back pain as well as radiation therapy for the underlying malignant process. In this study the authors evaluated a treatment paradigm of closed fracture reduction and fixation in which kyphoplasty was used, followed by single-fraction spinal radiosurgery performed with the CyberKnife.

METHODS

Twenty-six patients (six men and 20 women, mean age 72 years) with histologically confirmed pathological compression fractures (16 thoracic, 10 lumbar) were prospectively evaluated. For inclusion in the study, the patients' presenting symptoms were limited to pain without neurological deficits. Histological findings included 11 lung, nine breast, and four renal carcinomas, one cholangiocarcinoma, and one ocular melanoma. All patients underwent kyphoplasty of the affected vertebral body, for which a percutaneous transpedicular procedure was used. Fiducial markers that allow image guidance for CyberKnife radiosurgery were placed into the pedicles at the adjacent levels at the time of the kyphoplasty procedure. Patients then underwent single-fraction radiosurgery (at a mean of 12 days after kyphoplasty) in an outpatient setting. The tumor dose was maintained at 16 to 20 Gy to the 80% isodose line (mean 18 Gy). Treated tumor volume ranged from 12.7 to 37.1 cm3. Axial pain improved in 24 (92%) of 26 patients during the follow-up period of 7 to 20 months.

CONCLUSIONS

A combined kyphoplasty and spinal radiosurgery treatment paradigm was found to be safe and clinically effective for patients with pathological fractures without significant spinal canal compromise. This technique combines two minimally invasive surgical procedures, thereby avoiding the morbidity associated with open surgery while providing immediate fracture fixation as well as a single-fraction tumoricidal radiation dose.

Analysis of the functional muscle-bone unit of the forearm in pediatric renal transplant recipients

BACKGROUND

Renal transplantation in children and adolescents is associated with various skeletal complications. The incidence of spontaneous fractures appears to be increased, but the reasons for this are not entirely clear. Our objective was therefore to evaluate macroscopic bone architecture, mass, and strength by peripheral quantitative computed tomography (pQCT), a method that is not influenced by size-related artifacts. In addition, we investigated the muscle-bone relationship in these patients because under physiologic conditions bone strength continually adapts to increasing mechanical loads, that is, muscle force.

METHODS

In 55 patients (41 males) aged 15.8 +/- 4.1 years, we evaluated in a cross-sectional study 4.9 +/- 3.6 years after renal grafting bone mass, density, geometry, and strength of the radius, as well as forearm muscle size and strength, using pQCT at the proximal and distal radius, radiography of the second metacarpal shaft and hand dynamometry. Data were compared to a large cohort (N= 350) of healthy children.

RESULTS

Muscle mass and force were adequate for body size in pediatric renal transplant recipients. However, the radial bone was characterized by an inadequately thin cortex in relation to muscular force, as shown by a reduced height-adjusted cortical thickness both at the proximal (-0.83 +/- 1.12 SDS) and distal radius (-0.52 +/- 1.69 SDS), the metacarpal shaft (-0.54 +/- 1.35 SDS), and by a reduced relative cortical area (-0.90 +/- 1.13 SDS), while the mineralization of trabecular bone was unaltered. As a consequence of cortical thinning, the Strength-Strain Index that reflects the combined strength of trabecular and cortical bone was reduced in these patients.

CONCLUSION

While bone mineral density of the forearm is not decreased in pediatric renal transplant recipients, bone strength in relation to muscular force is reduced. This alteration may contribute to the increased propensity for fractures in these patients.

Advances in MR imaging of vertebral collapse

Vertebral collapse is a frequently encountered entity in clinical practice. While diagnosing acute, benign traumatic types is usually not complicated, difficulties arise in determining the etiology of vertebral collapse when there is no history of significant trauma, especially in older populations. Considering up to one-third of vertebral collapse in patients with a known primary malignancy are benign, the diagnosis becomes even more difficult when there is a history of malignancy. Additionally, because primary cancer patients may be immunocompromised, the possibility of infectious vertebral collapse should also be entertained. The purpose of this article is to review all recent magnetic resonance imaging aspects of differentiating osteoporotic, malignant, and infectious vertebral collapse.

HIV-assoziiertes Lymphom ? ungew�hnliche Ursache einer pathologischen Unterkieferfraktur

Despite the introduction of highly active antiretroviral therapy (HAART), diffuse large B-cell lymphoma (DLBCL) remains a common malignancy in human immunodeficiency virus (HIV)-infected patients, especially the plasmablastic variant. About 50% of lymphomas in HIV patients are extranodal and half of them occur in the head and neck area. The main oral symptoms are pain, swelling, numbness and tooth mobility. We report the case of a 52-year-old patient with a known HIV infection and fracture of the angular region of the mandible. The fracture did not unite following open reduction and osteosynthesis. A biopsy performed at the time of revision revealed the diagnosis of a primary lymphoma in the mandible. After chemotherapy had induced complete remission of the lymphoma and autogenous iliac crest bone grafting had been performed the fracture united. Primary lymphoma in the mandible is a disease that presents with a nonspecific radiological appearance which may mimic osteomyelitis or periodontal pathology. A rapid and accurate diagnosis is critical for the appropriate treatment. In our experience HIV-positive patients with mandibular fracture should be treated according to the guidelines established for HIV-negative patients. However, risky compromises such as intraoral approach or hazardous fracture fixation should be avoided.

Brown tumor of the femur associated with double parathyroid adenomas

Severe parathyroid bone disease is a rare clinical presentation of primary hyperparathyroidism. Double parathyroid adenomas are even more rare cause of primary hyperparathyroidism. The authors present a case of double parathyroid adenomas in a 48-year-old man, who presented with painful left lower limb swelling, which was slowly growing in size in the last 20 years. Magnetic resonance imaging revealed a cystic bony lesion and coincidentally, a urinary bladder calculus. Biopsy of the mass revealed giant cell lesion. Laboratory investigations showed hypercalcemia and hypophosphatemia with elevated parathyroid hormone level. A computerized tomography scan of the neck delineated an adenoma of the left superior parathyroid gland, which was surgically removed. The left inferior parathyroid was also enlarged and was removed. Histological diagnosis confirmed double parathyroid adenomas. The rarity and the interesting clinical presentation of such association are discussed.

MR appearance of SONK-like subchondral abnormalities in the adult knee: SONK redefined

OBJECTIVE

To investigate the MR characteristics of SONK-like (spontaneous osteonecrosis of the knee) subchondral abnormalities in the adult atraumatic knee and to recategorize these patients into two subgroups: a subacute to chronic process associated with osteoarthritis and an acute process associated with insufficiency fractures.

DESIGN

We retrospectively examined the knee MRIs of 39 patients with non-specific interpretations of osteochondral abnormalities.

PATIENTS

There were a total of 52 subchondral lesions without any known traumatic event and no prior surgery. All lesions evaluated had MR features previously ascribed to SONK. Several MR characteristics were then assessed: presence or absence of a line, size, zonal location, T1 and T2 signal, associated marrow edema, associated ipsilateral meniscal tear, and associated ipsilateral cartilage defects.

RESULTS AND CONCLUSIONS

The abnormalities with linear components (insufficiency fractures) tended to be larger (P<0.01) and were associated with a severe amount of marrow edema (P<0.0001) consistent with an acute process. The non-linear abnormalities were more associated with cartilage defects (P=0.01) and less marrow edema consistent with osteoarthritis and a subacute to chronic process. This association of SONK-like abnormalities with osteoarthritis and insufficiency fractures casts doubt on the validity of the term "spontaneous osteonecrosis" as it is currently applied, and further investigation into the separate etiologies of these subchondral marrow lesions is needed.

[Metaloosteosynthesis in the pathological fracture of the bone with benign and malignant tumors]

Metaloosteosynthesis of pathological fractures of bone on the background of bone tumors was carried out in 56 patients in the department of tumors of locomotion system. The good results of the treatment were obtained. In 42% of the cases it was possible to reconstruct the function of extremities. 53% of patients succeeded to avoid amputation or exarticulation of an extremity.

Osteoporotic Spinal Deformity

This review article develops a biomechanical rationale for the clinical consequences and treatment of osteoporotic vertebral body compression fracture. In patients with osteoporotic vertebral fractures and spinal deformity, altered spinal biomechanics and global spinal imbalance are important factors in the increased morbidity and mortality reported in this population. Severe spinal deformity impairs physical functioning, health, and quality of life. The spinal deformity itself, independent of pain, is a significant cause of disability. Spinal deformity is also an independent risk factor for hip fracture. Treatments directed at osteoporotic vertebral compression fractures should ideally address spinal deformity as well as pain. Balloon kyphoplasty, the minimally invasive technique of reduction and internal fixation of osteopenic vertebral body compression fractures that addresses pain and spinal deformity, is discussed.

[Giant cell tumor of bone. An evaluation of 87 patients]

AIM

Giant cell tumor (GCT) of bone is a very peculiar and interesting tumor due to of its biological behavior and the phenomenon of pulmonary metastases of a histologically benign tumor. We present the results of a retrospective study.

METHODS

Between 1965 and 2002 we treated 87 patients, 54 women and 33 men, for a GCT of bone. The average age of the patients was 28.2 (range 8-72) years. The median follow-up time was 91 months. 63 patients (72.4%) were hospitalized with a primary tumor. Twelve of these patients (19 %) had a pathological fracture. 24 patients (27.6%) presented with local recurrence. 7 tumors were malignant GCT of bone, 80 tumors were benign. According to the classification of Campanacci, 9 patients (10.3%) were diagnosed in stage I, 42 (48.3%) in stage II, and 36 (41.4%) in stage III. Surgical procedures were intralesional curettage and packing with cement in 36 patients, and bone-grafting in 7. In 35 cases we performed a wide resection, and in nine an amputation.

RESULTS

Local recurrence was observed in 11 patients (12.6%), all of them were benign GCT. Local recurrences were followed by an intralesional curettage and bone-grafting in three cases (42.8%), packing with cement in seven (19.4%). Three patients with local recurrence (27.3%) also had synchronous pulmonary metastases. All patients diagnosed with benign GCT are still alive. 3 out of 7 patients with malignant GCT died from progression of metastatic disease.

CONCLUSION

To reduce the risk of local recurrence and pulmonary metastases, we recommend an adjuvant therapy of GCT.

[Pathological fracture in fibrous histiocytoma of the proximal radial metaphysisJoint-preserving stabilization with the IP-XXS nail]

In this paper the authors report on a rare site for a benign bone lesion. They describe the clinical, radiological diagnostic, and therapeutic procedures for a benign fibrous histiocytoma (BFH) of the proximal radial metaphysis. Good results of operative treatment after excochleation, transplantation of an autologous bone chip, and stabilization with the IP-XXS nail are presented.

Tuberculosis manifesting as multifocal lytic cortical lesions in the femur

Tuberculosis remains a major international health problem despite advances in radiological diagnosis and antituberculous therapy. Disseminated tuberculous infection affecting a single bone and manifested as multifocal lytic cortical lesions is rare and unusual. We report on a 50-year-old man with multifocal involvement of the femur by tuberculosis and demonstrate positive reaction using tuberculosis-polymerase chain reaction on formalin-fixed, paraffin-embedded histological specimens.

Treatment considerations for vertebroplasty in men

BACKGROUND AND PURPOSE

Vertebroplasty is now a widely accepted image-guided intervention in patients with compression fracture. The purpose of this report is to look specifically at the male population undergoing vertebroplasty and identfy the management considerations distinct to men.

METHODS

The hospital medical records and radiographic studies of 24 men treated with vertebroplasty between February 1999 and November 2000 were retrospectively reviewed.

RESULTS

Five patients presented with idiopathic or secondary osteoporosis. In two of these five men, malignancies were discovered by core biopsies taken at the time of vertebroplasty. Thirteen patients (54%) had secondary osteoporosis. Of this group, 10 patients (42%) were steroid dependent and three (13%) were hypogonadal. Five patients (21%) had traumatic events leading to fracture. One presented with known metastases.

CONCLUSION

Primary osteoporosis in men is unusual. In male patients without a definable cause of osteoporosis, known metastatic disease, or a significant history of trauma, the routine performance of a vertebral biopsy through the vertebroplasty needle before the injection of bone cement is indicated to identify unexpected neoplasm.

Small cell carcinoma metastatic to the mandible. Report of a case

Small cell carcinoma either primary or metastatic is an uncommon malignancy in the oral and perioral tissues. We are reporting such a case.

Single shot fast spin echo diffusion-weighted MR imaging of the spine

PURPOSE

This study aims to evaluate the usefulness of single shot fast spin echo diffusion-weighted MR imaging (DWSSFSE) in differentiating malignant metastatic tumor infiltration of vertebral bone marrow from benign vertebral fracture edema.

MATERIALS AND METHODS

Forty-six consecutive patients with 59 acute osteoporotic or traumatic vertebral fractures (mean age = 59) and 31 patients with 98 vertebral metastasis including 20 pathologic fractures (mean age = 53) were included in this study. Diffusion-weighted MR images were obtained by single-shot fast spin echo technique with diffusion gradient (b = 500 s/mm2, TR/TE: 5002/99) by using a 1.5 T MR scanner (Signa MR/i; GE Medical Systems, Milwaukee, WI, USA). T1- and T2-weighted images and short inversion time inversion-recovery (STIR) images were available in all 157 lesions, while contrast-enhanced images were available in 98 metastatic lesions. We evaluated signal intensity patterns on DWSSFSE in 157 lesions, which showed low signal intensity on T1-weighted images in both benign fractures and metastasis. The lesions on DWSSFSE were categorized as low, intermediate, and high signal intensity relative to presumed normal vertebra by concordant inspection of two experienced musculoskeletal radiologists.

RESULTS

In benign fractures, DWSSFSE images showed low signal intensity in 56 vertebrae (95%) in 43 patients (93%) and intermediate signal intensity in only 3 vertebrae (5%) in 3 patients (7%). On the other hand, metastases most commonly had low signal intensity in 57 vertebrae (58%) in 25 patients (80%), intermediate signal intensity in 35 vertebrae (36%) in 16 patients (52%), and high signal intensity in 6 vertebrae (6%) in 3 patients (10%). Thus, intermediate and high signal intensities are far more common than benign fractures. Such differences in signal intensity were statistically significant (chi-square test, P < .05). High or intermediate signal intensity on DWSSFSE was highly specific for the diagnosis of metastatic tumor infiltration of the spine (sensitivity: 42%; specificity: 95%; true positive rate: 93%; false negative rate: 52%).

CONCLUSIONS

DWSSFSE of the spine may be useful in differentiating metastatic tumor infiltration of vertebral bone marrow from benign fracture edema.