BACKGROUND: Osteolytic lesions caused by infection or metastatic disease of the spine can induce instability. Different surgical strategies are available to restore stability in this scenario, however little is known how various reconstruction techniques affect spinal biomechanics.
OBJECTIVE: To analyze and quantify the biomechanical effects of three different surgical reconstruction techniques in the treatment of a T12 osteolytic model.
METHODS: Finite element analysis of the thoracic spine with a T12 osteolytic lesion.
METHODS: Using CT scans from a 20-year-old man without structural deformity, simulation of an osteolytic lesion with a 50% defect at the posterior aspect of T12 vertebral body was created by a 490 N vertical force to T9. Next, three common instrumentation techniques treating the osteolytic lesion were modeled and biomechanically tested. These included: Model A, corpectomy with short segment fixation (T11-L1) and two long-segment instrumentations; Model B long segment fixation with triple rod construct; Model C long segment fixation with dual rod construct. A load of 480N was then applied on the spine models in vertically downward direction on T9. Von Mises stresses were measured (MPa) in the discs, vertebrae, and implants.
RESULTS: Model A demonstrated the lowest stress on construct material, adjacent vertebral bodies, and discs but increased stress on the instrumented vertebrae. Model B was more rigid and demonstrated lower construct stress compared to Model C. However, Model C had the lowest vertebral body stress in flexion, extension, and lateral bending in the most upper instrumented vertebral body, but the highest screw pull-out stress when compared to Model A and Model B.
CONCLUSIONS: This osteolytic T12 model provides unique biomechanical data that can help to tailor surgical strategies in select scenarios. While optimal outcomes are best achieved with a construct tailored to a specific patient\'s need for stabilization, our findings can be generalized for instances of cancerous lesions, low bone density, and infectious causes.
CONCLUSIONS: The results of this study can help with the choice of appropriate surgical reconstruction technique based on patient-specific characteristics.

This article presents a clinical case of a central giant cell granuloma (CGCG) resembling a periapical lesion of endodontic origin. A 39-year-old, otherwise healthy male patient was referred to the department of oral and maxillofacial surgery for its diagnosis and subsequent management. The patient presented with an asymptomatic, progressively increasing intraoral swelling associated with the mandibular left para-symphysis region. On radiographic evaluation, a unilocular radiolucent lesion involving 33-34 teeth was noted. An incisional biopsy presented a giant cell lesion, following which surgical curettage was done. Histopathological examination was in accordance with the diagnosis of CGCG. Therefore, it is imperative for clinicians to accurately diagnose and rule out similarly presenting lesions.

Multiple myeloma is a disease of the plasma cells of the bone marrow, resulting in the proliferation and release of the monoclonal protein, which further causes end-organ damage. We report an unusual presentation of multiple myeloma, thereby insisting on the need for the treating physician to be aware of the various presentations that can be encountered in regular practice. It is often difficult to diagnose, and the diagnosis is usually made at a late stage of the disease. Even though uncurable, with recent advances, a proper regimen, newer chemotherapeutic agents, and stem cell transplantation, the disease can be brought into remission.

Erosive bony lesions are a frequent manifestation of numerous etiologies, spanning from malignancy and metabolic disorders to chronic inflammatory conditions like sarcoidosis. However, arteriovenous malformations (AVM) are a less prevalent etiology for this condition. The presentation of erosive bony lesions is diverse, influenced by factors such as age, gender, size, and extent of the lesion. Multiple imaging modalities are employed to achieve a diagnosis, including plain radiograph, Doppler ultrasound, computed tomography, angiography, and magnetic resonance imaging.

BACKGROUND: Neuroblastoma is the most frequent extracranial solid tumor occurring in childhood, representing approximately 28% of all cancers diagnosed in infants. Signs and symptoms of neuroblastoma vary with the site of development of the tumor and can mimic other diseases due to its extreme clinical variability. However, torticollis is not reported in the medical literature as a leading symptom of neuroblastoma.
METHODS: Here we report the case of a 3 years-old girl with fever and neck stiffness. Blood tests revealed a mild anemia and a rise in inflammatory markers. CT-scan showed a solid, heterogeneous, predominantly hypodense surrenal mass with eccentric calcification and extensive inhomogeneity of the vertebral metamers. Blood tests revealed raised serum levels of Neuron-Specific Enolase. At the 24-hours urine collection urinary catecholamines were greatly increased. A course of chemotherapy for neuroblastoma was promptly started with immediate clinical improvement.
CONCLUSIONS: This case shows that the presence of torticollis could be a chief complaint of neuroblastoma. To our knowledge, neuroblastoma is not mentioned among life-threatening underlying conditions of torticollis in most recent literature reviews.

UNASSIGNED: Gorham-Stout disease is a rare condition of unknown prevalence and unknown exact cause. Its pathogenesis is based on enhanced osteoclastic activity leading to bone resorption and bone replacement by distended lymphatic vessels. Because of its rarity and a various range of symptoms the disease may give, diagnosis is challenging and a strong index of suspicion is required. Although it is a benign condition, the prognosis may be unpredictable. The treatment options suggested so far are limited, and every case should be provided with the best individual approach. Herein, we present a case report of Gorham-Stout disease managed with a regular lump drainage with a good response and control of the patient symptoms over a period of 20 years.
UNASSIGNED: A 23-year-old male was admitted to the Head and Neck Cancer Clinic with a 6-month history of a left-sided neck lump. Other symptoms reported were neck pain and general weakness. The basic laboratory tests were within normal limits. On physical examination, a large round lump on the left side of a patient\'s neck and left armpit were noticed. They were about several centimeters in diameter, soft on palpation, but firmly attached to the underlying tissue. CT scan revealed large lymphatic left-sided masses of the neck and axillary fossa and multiple osteolytic lesions in the patient\'s vertebrae. Together with the biopsy findings and imaging studies, a diagnosis of Gorham-Stout Syndrome was made. The patient was then scheduled for a regular cystic drainage with good control of a disease for over a period of 20 years.
UNASSIGNED: Gorham-Stout disease is a rare challenging condition, and the available treatment options remain sparse. Although surgical approach is effective, it is not always possible. In addition, the risk of radiotherapy-induced malignancy shows that this therapy may eventually result in unfavorable response. Depending on symptoms and the disease location, this condition requires an individual treatment plan. The presented case illustrates that a minimally invasive approach may result in a good control of the Gorham-Stout syndrome and may stand as an alternative treatment option for some patients with this condition.

This case report describes a 52-year-old immunocompromised man diagnosed with disseminated Mycobacterium abscessus complex (MABC) infection. The patient had a history of malignant lymphoma and presented with fever and polyarthritis that lasted 3 weeks. Upon initial evaluation, blood and synovial fluid cultures from the swollen joints were negative. Reactive arthritis or rheumatoid arthritis was suspected as the cause of inflammatory synovitis in multiple joints. Administration of prednisolone followed by an interleukin-6 inhibitor improved the fever, but polyarthritis persisted, and destruction of the left hip joint was observed. Two months later, M. abscessus was detected in a blood culture and right shoulder joint synovium, leading to a final diagnosis of disseminated MABC infection. The joint symptoms resolved with combined antimicrobial therapy using amikacin, azithromycin, and imipenem/cilastatin. To date, 12 cases of disseminated MABC infection with osteoarticular manifestations have been reported. A total of 13 cases, including the present case, were reviewed. Seven patients had bone involvements, five had joint involvement, and the remaining one had bursa involvement. All the cases with joint involvement, except for our case, presented with monoarthritis. MABC infection is diagnosed based on the demonstration of MABC itself. Clinicians should keep disseminated MABC infection in mind as a possible cause of persistent arthritis. As demonstrated in our case, multiple replicate cultures of blood or specimens from the affected sites may be needed to detect it.

BACKGROUND: The success of orthopedic interventions for periacetabular osteolytic metastases depends on the progression or regression of cancer-induced bone loss.
OBJECTIVE: To characterize relative bone mass changes following percutaneous radiofrequency ablation, osteoplasty, cement reinforcement, and internal screw fixation (AORIF).
METHODS: Of 70 patients who underwent AORIF at a single institution, 21 patients (22 periacetabular sites; average follow-up of 18.5 ± 12.3 months) had high-resolution pelvic bone CT scans, with at least one scan within 3 months following their operation (baseline) and a comparative scan at least 6 months post-operatively. In total, 73 CT scans were measured for bone mass changes using Hounsfield Units (HU). A region of interest was defined for the periacetabular area in the coronal, axial, and sagittal reformation planes for all CT scans. For 6-month and 1-year scans, the coronal and sagittal HU were combined to create a weight-bearing HU (wbHU). Three-dimensional volumetric analysis was performed on the baseline and longest available CT scans. Cohort survival was compared to predicted PathFx 3.0 survival.
RESULTS: HU increased from baseline post-operative (1.2 ± 1.1 months) to most recent follow-up (20.2 ± 12.1 months) on coronal (124.0 ± 112.3), axial (140.3 ± 153.0), and sagittal (151.9 ± 162.4), p < 0.05. Grayscale volumetric measurements increased by 173.4 ± 166.4 (p < 0.05). AORIF median survival was 27.7 months (6.0 months PathFx3.0 predicted; p < 0.05). At 12 months, patients with >10% increase in wbHU demonstrated superior median survival of 36.5 months (vs. 26.4 months, p < 0.05).
CONCLUSIONS: Percutaneous stabilization leads to improvements in bone mass and may allow for delays in extensive open reconstruction procedures.

The presence of bone marrow focal lesions and osteolytic lesions in patients with multiple myeloma (MM) is of high prognostic significance for their individual outcome. It is not known yet why some focal lesions seen in MRI, reflecting localized bone marrow infiltration of myeloma cells, remain non-lytic, whereas others are associated with destruction of mineralized bone. In this study, we analyzed MRI characteristics of manually segmented focal lesions in MM patients to identify possible features that might discriminate lytic and non-lytic lesions.
The initial cohort included a total of 140 patients with different stages of MM who had undergone both whole-body MRI and whole-body low-dose CT within 30 days, and of which 29 satisfied the inclusion criteria for this study. Focal lesions in MRI and corresponding osteolytic areas in CT were segmented manually. Analysis of the lesions included volume, location and first order texture features analysis.
There were significantly more lytic lesions in the axial skeleton than in the appendicular skeleton (p = 0.037). Out of 926 focal lesions in the axial skeleton seen on MRI, 544 (59.3 %) were osteolytic. Analysis of volume and first order texture features showed differences in texture and volume between focal lesions in MRI with and without local bone destruction in CT, but these findings were not statistically significant.
Neither morphological imaging characteristics like size and location nor first order texture features could predict whether focal lesions seen in MRI would exhibit corresponding bone destruction in CT. Studies performing biopsies of such lesions are ongoing.

UNASSIGNED: A giant cell tumor (GCT) is a benign tumor of bones which commonly arises from epiphysis of long bones. The tumor is locally aggressive and rarely metastasizes to the lungs. GCT of small bones of the foot and ankle is very rare. The GCT of the talus is very rare, and only a few case reports and series are described in the literature. In general, the GCT is monostotic, and few incidences of multicentricity have been described in the foot and ankle bones literature. Here are the findings of our case GCT of talus and reviews of earlier literature.
UNASSIGNED: We present a case of a GCT of the talus in a 22-year-old female. Patient presented with pain in ankle with mild swelling and tenderness at ankle. Radiograph and Computer tomography scan conformed an eccentric osteolytic lesion on anterolateral part of talus body. Magnetic resonance imaging showed no extra osseous extension or articular surface breach. Biopsy conformed the lesion to be giant cell tumor. The tumor was reated with curettage and bone cement filling.
UNASSIGNED: Giant cell tumor of talus is extremely rare and presentation of these tumor may change. Curettage and bone cementing are an effective method of treatment. It gives early weight bearing and rehabilitation.