infection can be limited to a single portion of bone or can involve several regions such as marrow , cortex , periosteum , and surrounding soft tissue . exogenous osteomyelitis is more common ( 47% ) than hematogenous osteomyelitis ( 19% ) or osteomyelitis secondary to vascular insufficiency ( 34% ) . a 21-year - old male reported with a chief complaint of pus discharge and exposed bone on the right side of the face below eye since 6 months . patient gave alleged history of blunt trauma to skull 9 months back after which a massive swelling developed in the scalp . on computed tomography ( ct)-head , he was diagnosed with depressed fracture of parietal bone with extradural hematoma [ figure 1 ] . patient was put on parenteral antibiotics for 7 days and was kept under regular follow - up . copious pus discharge was noticed on incision and drainage by neurosurgeons and was kept under antibiotic coverage for 2 weeks . pus continued to drain from the incision site intermittently for 2 months , in the meantime patient noticed swelling over the right cheek with redness of the right eye . by the time , the patient reported to us , he had developed a sinus with pus discharge from a wound measuring 1 cm  0.5 cm at the lateral one - third of infraorbital rim with exposed underlying bone [ figure 2 ] while the lesion over parietal region of scalp was regressed by then . subgaleal abscess with depressed fracture of parietal bone exposed bone and pus discharge from lateral one - third of infraorbital rim a presumptive diagnosis of osteomyelitis was made with differential diagnosis as hematogenous osteomyelitis , tuberculous osteomyelitis , and eosinophilic granuloma . the pus was sent for culture and sensitivity and showed growth of coagulase - negative staphylococcus sensitive to ciprofloxacin , cefoxitin , and clindamycin . radiographically , occipitomental view revealed an ill - defined osteolytic lesion in the right zygomatic bone . ct scan revealed lytic lesions in relation to the right zygomatic bone with evidence of sclerosis [ figure 3 ] . partial sequestration with curettage of zygomatic bone without involvement of lateral canthal ligament was carried out under general anesthetic ( ga ) [ figure 4 ] and patient was kept under antibiotic coverage of clindamycin and ornidazole for 2 weeks . three - dimensional computed tomography scan window showing lytic lesion of zygomatic bone partial sequestration with curettage of zygoma follow - up after 1 year typically , osteomyelitis is classified as chronic or acute , depending on the length of time during which the infection or the symptoms were present . the traditional classification system of waldvogel et al . is derived from hematogenous or contiguous focus in origin . in addition , osteomyelitis can also be classified as endogenous ( hematogenous in origin ) or exogenous ( by trauma ) . osteomyelitis in adults is most often subacute or chronic and usually ensues from a traumatic insult to the involved area . exogenous osteomyelitis is more common ( 47% ) than hematogenous osteomyelitis ( 19% ) or osteomyelitis secondary to vascular insufficiency ( 34% ) . in posttraumatic osteomyelitis , microorganisms can be introduced directly into the bone or via contiguous spread from injury to overlying soft tissue . in hematogenous osteomyelitis infection it is a type of osteomyelitis more commonly associated with children where it tends to occur in the rapidly growing and highly vascular metaphysis of growing bones . , it most commonly involves the vertebral bones , the next common sites are the flat bones of the axial skeleton such as the clavicle and pelvis . however , as stated in the literature , osteomyelitis of midface itself is a rare entity . as the swelling and pus discharge over zygomatic bone was seen after 3 months of depressed fracture of parietal bone , relation between both episodes was evident . contrast - enhanced ct - head showed evidence of hypodense collection in subgaleal layer of the scalp in parieto - occipital region measuring 9 cm  3 cm , diagnosed as parietal bone fracture with subgaleal abscess [ figure 1 ] . following trauma , there was the formation of subgaleal hematoma which eventually got infected and formed abscess . the foci of infection in contiguity to parietal bone led to posttraumatic ( exogenous ) osteomyelitis . superficial temporal vein begins at the vertex of skull in a plexus which communicates with the frontal and supraorbital veins , with corresponding vein on the opposite side , and with the posterior auricular vein and occipital vein . from this network , frontal and parietal branches arise , unites above zygomatic arch to form a trunk of vein , which is joined in this situation by the middle temporal vein , from the substance of temporalis . it crosses the posterior root of the zygomatic arch , enters the substance of the parotid gland , and unites with the internal maxillary vein to form posterior facial vein [ figure 6 ] . vascularity of scalp and face thus , it is evident that there was seeding of the microorganisms from the distant foci , i.e. , from the parietal bone to the zygomatic bone that resulted in osteomyelitis of zygomatic bone which was of hematogenous origin . in the majority of cases , posttraumatic osteomyelitis is a clinical diagnosis , definitively confirmed by microorganisms isolated from the biopsy specimen and histopathological examination . a high index of suspicion and a thorough approach to the evaluation of patient are therefore essential to establish a diagnosis . the authors certify that they have obtained all appropriate patient consent forms . in the form the patient(s ) has / have given his / her / their consent for his / her / their images and other clinical information to be reported in the journal . the patients understand that their names and initials will not be published and due efforts will be made to conceal their identity , but anonymity can not be guaranteed . the authors certify that they have obtained all appropriate patient consent forms . in the form the patient(s ) has / have given his / her / their consent for his / her / their images and other clinical information to be reported in the journal . the patients understand that their names and initials will not be published and due efforts will be made to conceal their identity , but anonymity can not be guaranteed .
osteomyelitis is an inflammatory condition of bone involving the medullary cavity , the haversian system , and the adjacent cortex . according to literature review osteomyelitis of zygomatic bone secondary to the depressed fracture of the parietal bone 
 never reported . here 
 we report a case of osteomyelitis of zygomatic bone which develops 3 month after the depressed fracture of parietal bone .