A prognostic classification of proximal humerus fractures: the cephalic extension staging.

PURPOSE: Recent publications emphasized the role of dorsomedial metaphyseal extension of humeral head as predictor of ischemia after complex proximal humerus fractures (PHFs). We evaluated on preoperative 3D CT scan of PHFs the surface of this metaphyseal extension and its prognostic value on the occurrence of avascular necrosis (AVN). METHODS: We followed a series of 25 fixations of complex PHF which had a preoperative 3D CT scan and measured the surface area of the posterior metaphyseal extension (PME) of the head. Using approximations, we calculated the ratio between the PME surface area (PMS) and the articular surface area of the head (HS). The PMS/HS ratio was analyzed against the risk of AVN. RESULTS: The measurement of the PMS/HS ratio emphasizes the significance of PME. The incidence of AVN is correlated with the magnitude of PME. Therefore, we include the PME as a fifth element in the characterization of complex PHFs and we propose a 4-stage prognostic classification based on the number of extensions of the humeral head. The head may have 3 extensions: posteromedial (PME), lesser tuberosity (LTE) and greater tuberosity (GTE). The risk of AVN decreases with the number of extensions of the head. CONCLUSION: Our study demonstrates a correlation between the occurrence of AVN and the size of PME in complex PHF cases. We propose a four-stage classification system to facilitate treatment decision-making between fixation and prosthesis.

Inflammatory low back pain with radiculopathy revealing epidural disintegration of a bullet complicated by lead poisoning.

Inflammatory low back pain with radiculopathy is suggestive of cancer, infection or inflammatory diseases. We report a unique case of a 42-year-old patient with an acute inflammatory low back pain with bilateral radiculopathy associated with weight loss and abdominal pain, revealing the disintegration of a lead bullet along the epidural space and the S1 nerve root complicated by lead poisoning. Because of the high blood lead level of intoxication (>10 times over the usual lead levels) and the failure of repeated lead chelator cycles, a surgical treatment to remove bullet fragments was performed. It resulted in a significant decrease of pain and lead intoxication.

Bone in Anorexia.

Anorexia nervosa is a feeding disorder involving intentional weight loss. Restricted dietary intake leads to disturbed bone metabolism due to various factors, notably endocrine, that affect bone microarchitecture and incur risk of fracture. Mild to moderate anorexia shows a paradoxical increase in bone marrow adipose tissue, whereas severe forms show gelatinous transformation known as serous atrophy of bone marrow (SABM). Imaging assessment of the mineralized and adipose components uses several techniques: dual-energy X-ray absorptiometry, computed tomography, chemical shift magnetic resonance imaging (MRI), and single-voxel MR spectroscopy. SABM induces MRI bone signal disturbances that can be hard to interpret and may hinder visualization of the fracture line.

MFN2-associated lipomatosis: Clinical spectrum and impact on adipose tissue.

BACKGROUND: Multiple symmetric lipomatosis (MSL) is characterized by upper-body lipomatous masses frequently associated with metabolic and neurological signs. MFN2 pathogenic variants were recently implicated in a very rare autosomal recessive form of MSL. MFN2 encodes mitofusin-2, a mitochondrial fusion protein previously involved in Charcot-Marie-Tooth neuropathy. OBJECTIVE: To investigate the clinical, metabolic, tissular, and molecular characteristics of MFN2-associated MSL. METHODS: We sequenced MFN2 in 66 patients referred for altered fat distribution with one or several lipomas or lipoma-like regions and performed clinical and metabolic investigations in patients with positive genetic testing. Lipomatous tissues were studied in 3 patients. RESULTS: Six patients from 5 families carried a homozygous p.Arg707Trp pathogenic variant, representing the largest reported series of MFN2-associated MSL. Patients presented both lipomatous masses and a lipodystrophic syndrome (lipoatrophy, low leptinemia and adiponectinemia, hypertriglyceridemia, insulin resistance and/or diabetes). Charcot-Marie-Tooth neuropathy was of highly variable clinical severity. Lipomatous tissue mainly contained hyperplastic unilocular adipocytes, with few multilocular cells. It displayed numerous mitochondrial alterations (increased number and size, structural defects). As compared to control subcutaneous fat, mRNA and protein expression of leptin and adiponectin was strikingly decreased, whereas the CITED1 and fibroblast growth factor 21 (FGF21) thermogenic markers were strongly overexpressed. Consistently, serum FGF21 was markedly increased, and 18F-FDG-PET-scan revealed increased fat metabolic activity. CONCLUSION: MFN2-related MSL is a novel mitochondrial lipodystrophic syndrome involving both lipomatous masses and lipoatrophy. Its complex neurological and metabolic phenotype justifies careful clinical evaluation and multidisciplinary care. Low leptinemia and adiponectinemia, high serum FGF21, and increased 18F-FDG body fat uptake may be disease markers.

Bone imaging findings in genetic and acquired lipodystrophic syndromes: an imaging study of 24 cases.

OBJECTIVE: To describe the bone imaging features of lipodystrophies in the largest cohort ever published. MATERIALS AND METHODS: We retrospectively examined bone imaging data in 24 patients with lipodystrophic syndromes. Twenty-two had genetic lipodystrophy: 12/22 familial partial lipodystrophy (FPLD) and 10/22 congenital generalized lipodystrophy (CGL), 8 with AGPAT2-linked CGL1 and 2 with seipin-linked CGL2. Two patients had acquired generalized lipodystrophy (AGL) in a context of non-specific autoimmune disorders. Skeletal radiographs were available for all patients, with radiographic follow-up for two. Four patients with CGL1 underwent MRI, and two of them also underwent CT. RESULTS: Patients with FPLD showed non-specific degenerative radiographic abnormalities. Conversely, CGL patients showed three types of specific radiographic alterations: diffuse osteosclerosis (in 7 patients, 6 with CGL1 and 1 with CGL2), well-defined osteolytic lesions sparing the axial skeleton (7 CGL1 and 1 CGL2), and pseudo-osteopoikilosis (4 CGL1). Pseudo-osteopoikilosis was the sole bone abnormality observed in one of the two patients with AGL. Osteolytic lesions showed homogeneous low signal intensity (SI) on T1-weighted and high SI on T2-weighted MR images. Most of them were asymptomatic, although one osteolytic lesion resulted in a spontaneous knee fracture and secondary osteoarthritis in a patient with CGL1. MRI also showed diffuse fatty bone marrow alterations in patients with CGL1, with intermediate T1 and high T2 SI, notably in radiographically normal areas. CONCLUSIONS: The three types of peculiar imaging bone abnormalities observed in generalized lipodystrophic syndromes (diffuse osteosclerosis, lytic lesions and/or pseudo-osteopoikilosis) may help clinicians with an early diagnosis in pauci-symptomatic patients.

CT Features of Vertebral Venous Congestion Simulating Sclerotic Metastases in Nine Patients With Thrombosis of the Superior Vena Cava.

OBJECTIVE: The purpose of this retrospective study is to describe the CT features of vertebral venous congestion simulating sclerotic metastases in nine patients with thrombosis of the superior vena cava. MATERIALS AND METHODS: We analyzed all cases of obstruction of the superior vena cava recorded in our radiologic teaching files since 2006, to identify cases with vertebral venous congestion simulating sclerotic metastases. The following CT features were analyzed: the underlying cause, exact level, and length of the venous obstruction; the pattern of collateral venous pathways visualized as enlarged and densely opacified vascular channels; and the characteristics of the vertebral venous congestion. RESULTS: Nine patients referred for CT examinations between 2006 and 2014 were included in the present study. The pathways that underwent contrast enhancement included the anterior or lateral thoracic pathways in eight patients, the mediastinal pathways in seven patients, and the azygos and vertebral pathways in nine patients. Vertebral venous congestion was observed in 30 vertebrae and was specifically noted in the vertebral body (n = 25), pedicle (n = 11), lamina (n = 3), and spinous process (n = 1). The density of vertebral bone enhancement ranged from 413 to 1480 HU. The limits were well defined in eight lesions and ill defined in 22 lesions. In 23 lesions, a vessel was noted within the vertebrae, in close contact with the vertebrae, or in both locations. CONCLUSION: Development of a vertebral venous collateral system can lead to vertebral venous congestion, resulting in focal and patchy enhancement of the vertebrae, which can be mistaken for sclerotic metastases.

Open reduction and internal fixation of three- and four-part proximal humeral fractures by intra-focal distraction: observational study of twenty five cases.

PURPOSE: Reduction and fixation of proximal humerus fracture (PHF) by intra-focal distraction with a cemented device is seldom used. A cementless stem called JUST was developed to simplify and standardise reduction and fixation of three- or four-part fractures (3-/4-PFs). This study is designed to evaluate the performances of this device. In addition, we compared the results to those of a previous study based on cemented stems. METHOD: Twenty-five patients underwent surgery between 2009 and 2011: ten 3-PFs and 15 4-PFs, with a median age of 65.5 and 71 years, respectively. The reduction and fixation device comprises a staple placed in the humeral head and a cementless stem impacted in the diaphysis that works like a jack. Median follow-up was 28 months. RESULTS: For the ten 3-PFs, the median raw and weighted Constant score were 66.5 and 86, respectively. Only one case presented with secondary displacement. All fractures healed and there was only one case of avascular necrosis. For the 15 4-PFs, the median raw and weighted Constant score were 64 and 76, respectively. Only one case of secondary cephalic displacement was observed and no cases of tuberosity displacement were observed. All fractures healed except for one case of pseudarthrosis of the lesser tuberosity. Five cases of avascular necrosis were observed. CONCLUSIONS: This device resolves the mechanical difficulties relating to fixation of 3- and 4-PFs by providing stable fixation but does not prevent the risk of avascular necrosis. The cementless stem is more convenient but does not yield better results than the cemented stem.

Quickly progressive amyotrophy of the thigh: An unusual cause of rapid chondrolysis of the knee.

While rapidly destructive OA is more recognized in hip, we report the case of a 50-year-old woman who presented a rapid chondrolysis in the patellofemoral joint in a context of rapid loss of muscular strength. She had arthralgia, myalgia and proximal muscular deficit of the limbs. Creatine phospho kinase level was elevated and electromyogram exam showed a myogenic syndrome. Neither immune nor visceral disease was highlighted. As we suspected a polymyositis, we started corticosteroids and physiotherapy, then methotrexate and intravenous immunoglobulin. Concomitantly to the worsening of the muscular deficit and atrophy of hamstrings, she developed a persistent and disabling knee pain. Initial radiographs and magnetic resonance imaging (MRI) showed only a patellofemoral dysplasia and tiny cartilage damages. Because of aggravation of myalgia, we treated by mycophenolate mofetyl then rituximab. One year later, the knee remained painful and swollen. MRI showed signs of advanced osteoarthritis including an important loss of cartilage with an atrophy of hamstrings. Several articular corticosteroids injections were done. In the same time, the evolution of the muscular disease was unusual. Another histological analysis of muscle has highlighted a genetic myopathy due to mutation of calpain. Immunosuppressive treatments were stopped and a total joint replacement was performed. We show for the first time a case of rapid chondrolysis of patellofemoral joint related to a severe genetic myopathy.

Is sarcoma a complication of arterial femoro-popliteal bypass?

Angiosarcoma is a rare neoplasm comprising 1 to 2% of soft tissue sarcoma. This tumor has been associated with previous irradiation, exposure to toxins and the presence of foreign bodies. A case report of an epithelioid angiosarcoma that developed at the site of an arterial femoro-popliteal bypass using autologous vein is described. The initial presentation looked like a painful popliteal cyst. Chronic fibrosis secondary to the thrombosis could play a role in the tumorogenesis of this uncommon tumor. This case illustrates that sarcoma may be a late complication of vascular bypass and may have a rheumatologic presentation.

Bone involvement in Erdheim-Chester disease: imaging findings including periostitis and partial epiphyseal involvement.

PURPOSE: To retrospectively review the bone findings at radiography, scintigraphy, computed tomography (CT), and magnetic resonance (MR) imaging in 11 patients with immunohistochemical and histologic proof of Erdheim-Chester disease. MATERIALS AND METHODS: This study was designed as a retrospective review; approval of the institutional review board and patient consent were not required for this type of study. Eleven patients (eight men and three women; mean age, 49 years; range, 17-68 years) with Erdheim-Chester disease underwent conventional radiography of the skeleton and bone scintigraphy. Two patients underwent CT of the femora and 10 underwent CT of the skull. Eight patients underwent MR imaging. Conventional radiographs, bone scintigrams, CT scans, and MR images were reviewed in consensus by four musculoskeletal radiologists. RESULTS: All 11 patients had involvement of the long bones and normal axial skeleton, hands, and feet. Bilateral and symmetric osteosclerosis of the diaphysis of the long bones was present in 52 (26 pairs) (98%) of the 53 bone lesions visible on conventional radiographs. Osteosclerosis was heterogeneous in 65% of the patients and homogeneous in 35%. Diaphysis was involved in 100% and metaphysis in 44 (83%) lesions. Partial epiphyseal involvement sparing the subchondral bone was present in 24 (45%) lesions. Periostitis was seen in 35 (66%) and endosteitis in 50 (94%) of the 53 long bones involved. Bone scintigraphy depicted tracer uptake in all bone lesions visible on radiographs. Skull and face bone lesions were present in two patients. MR imaging depicted a replacement of the normal fatty bone marrow by heterogeneous signal intensity on T1- and T2-weighted spin-echo images. Lesion extent, epiphyseal involvement, and periostitis were clearly depicted at MR imaging. CONCLUSION: This series provides a detailed description of bone involvement in Erdheim-Chester disease. Periostitis and partial epiphyseal involvement of the long bones are also features of this disease. (c) RSNA, 2005.

Isolated thoracic spine lesion: is this the presentation of a SAPHO syndrome? A case report.

A case of an isolated lesion of the thoracic spine attributed to SAPHO syndrome is presented. A 51-year-old man was referred for inflammatory pain in the thoracic spine. The general examination was normal (especially cutaneous and rheumatologic examinations). Laboratory analysis showed only a mild inflammatory reaction. Standard radiographs showed partial condensation of T8. Computed tomography showed osteolysis of the anterior corner of T8, and MRI revealed an abnormal signal of T8, with enlargement of the prevertebral soft tissue. Percutaneous and thoracoscopic biopsies showed a nonspecific inflammatory process, and cultures were sterile. Initially, several diagnoses were advanced: infectious spondylitis, malignant tumor, lymphomas, Paget disease, seronegative spondyloarthropathies and finally atypical SAPHO syndrome. Three months later, the patient experienced more pain. General examination was still normal. The radiological findings worsened, while the inflammatory blood tests were normal. A new thoracoscopic biopsy revealed a nonspecific inflammatory process. A diagnosis of SAPHO syndrome was made, despite the lack of typical lesions. Dramatically improving with anti-inflammatory therapy, the patient's condition was favorable at 3-year follow-up. This atypical presentation of an isolated lesion in the spine makes the diagnosis of a SAPHO syndrome difficult but possible. Spine surgeons must be aware of this rare entity, to avoid misdiagnosis and unnecessary repeated surgical biopsies.