 Greetings everyone. The topic for my presentation is a rare disabling heterotrophic ossification disorder fibrodysplasia ossificens progressiva. I am the author Dr. Riva and I have written it with my co-author Dr. Bhavna Arora. It is also known as Munchmere's disease and Stone Man's disease. It is a rare progressive pediatric autosomal disorder which is characterized by heterotrophic ossifications and oscious bridgings. It has a prevalence of one in two million cases. Most cases have a missense or base dilation mutation of the ACVR1 or the ALC2 gene. The ossification it begins early in the soft tissues and later it involves the deeper structures like the muscles, the ligaments, the tendons and all of this ossification causes significant restriction of the motion. At later stages when the progression of this ossification is so severe it causes thoracic insufficiency which is responsible for decreased lifespan of around 40 years of these patients. There are certain associated abnormalities which are the congenital deformities of the great toe of which the most common is the congenital halosus valgus along with tauticalis vertebral deformities, tibial tumors and multiple soft tissue swellings due to the heterotrophic ossifications. The patient usually is around 5 to 15 years of age and they have a congenital toe deformity in the form of halosus valgus and it may be the only abnormality which is noted early in the infancy. The onset of the atopic ossification is known to be caused by certain triggering factors which include trauma, surgery, intramuscular injections and severe exercises. When the ossification sets in, the typical extra skeletal ossification become evidence as abnormal areas of osteogenesis in X-ray and CT. MRI is also used in cases of pre-ocious soft tissue swellings. Talking about our study, a 12-year-old female presented in our opity with complaints of severe body and backache along with multiple soft tissue swellings over the back since a few weeks. The pain had been persistent despite being on various analgesics for the same. There was no past history of any trauma, surgery or chronic illnesses. A clinical examination was done and was found to be normal except for a few tender swellings on the back. These swellings were firm, non-mobile, non-fluctuant and were seen diffusely involving the subcutaneous tissues of the back. No abnormality of the toes were noted in our patient. A CT examination was done which revealed heterotrophic calcifications in the subcutaneous and muscular plane of the neck and back with hypodent soft tissue thickenings at the site of ossifications, these in all the trapezius and the erectus spinae muscle. There was also fusion of the transverse processes by thick ossified transverse band in the cervical and the upper thoracic spine causing straightening of these spinal segments. MRI of the patient revealed ill-defined bone-intensility lesions within the subcutaneous plane predominantly in the lower back region. Here is an image showing the clinical case of multiple soft tissue swellings of the patient over the back. A CT was performed for the same and we can see that there are multiple heterotrophic calcified lesions or calcifications and the soft tissues of the back. These were more predominant in the lower part, these involve the muscles as well as the soft tissue. Looking at the sagittal sections we can see that there are various soft tissue ossifications noted in the back of the patient. We can also see that the cervical spine of the patient is straightened, this was due to the oscious bridging of the trans and ossification of the transverse processes. An actual T2MR of the patient is showing bone-intensity lesions in the soft tissues of the back. So final diagnosis of early fibrodisplasia ossificens progressiva was made. The disease needs to be differentiated from various disorders especially in juvenile population. One of the differentials is progressive oscious heteroplasia which could be differentiated on genetic grounds and aggressive juvenile fibromatosis which lacks the characteristic calcifications. Concluding fibrodisplasia ossificens progressiva is a rare disorder which cannot be diagnosed prenatally and it is characteristically disabling and fatal. So it is important to know the clinical spectrum and the associations of this disease. The characteristic abnormalities of the great toe are present in most but not in all patients. Our case is an example of these conditions. Ostocondromita, middle-layer ossification, demyelination, lymphedema and venous thrombosis may also occur. Early in the disease the routine examination and radiographic images are not of much significance. Later when ossification is set then CT can clearly reveal the typical findings. MR can reveal preoscious lesions usually appearing as soft tissue swellings and skeletal malformations. Drugs can only provide symptomatic relief at the time of flare ups. Although no effective treatment for the disease has yet been identified, early in thromb diagnosis would help in preventing various triggering factors which may cause flaring of the disease. With the ongoing search for biological targets for the disease treatment, our findings add to the scarce pool of available cases and findings of this disease. Here are a few references. Thank you.