extraosseous soft - tissue uptake of technetium-99 m methylene diphosphonate ( tc-99 m mdp ) can occur in number of occasions .
cancer patients those undergoing bone scintigraphy will have abnormal uptake , which should be differentiated from benign and metastasis in a planar bone scan .
single - photon emission tomography - computed tomography ( spect / ct ) help in localizing uptake to the muscle hematoma is not reported yet .
a 79-year - old man with prostate cancer and coagulation disorder was referred for a bone scan because of left shoulder pain .
a bone scan was performed to assess for any skeletal involvement , especially in the shoulder .
a total of 20 mci ( 740 mbq ) mdp was injected intravenously and imaging was performed 3 h later using a large field of view , dual headed gamma camera fitted with a low - energy , high - resolution collimator .
anterior whole - body images showed intense uptake in the left axilla [ figure 1 ] .
spect ct of the chest [ figures 2 and 3 ] was performed to rule out whether the uptake is in the humerus , but it showed a hematoma in the left brachialis muscle , which he developed due to his coagulation disorder . a hematoma was confirmed on fine - needle aspiration and resolved spontaneously over the next 4 - 5 weeks .
follow - up bone scan carried out after 6 months showed resolution of uptake in the left axilla [ figure 4 ] .
technetium-99 m methylene diphosphonate whole body bone scan showing increased uptake noted in the left axilla ( arrow ) and no other site of metastasis coronal computed tomography images showing hematoma in the left brachialis muscle fused coronal single - photon emission tomography - computed tomography images localises tracer uptake to the hematoma in the left brachialis muscle follow - up technetium-99 m methylene diphosphonate whole body scan shows resolution of uptake in the left axilla after 6 months
localization of bone imaging agents like tc-99 m mdp and tc-99 m hydroxymethylene diphosphonate has previously been described in abdominal and pelvic hematomas .
extraosseous soft - tissue concentration of these radiotracers in the chest has also been reported in soft - tissue hematoma , a benign intrapulmonary calcified focus , squamous cell carcinoma of the pleura and pulmonary alveolar microlithiasis .
proposed mechanism leading to increased extraosseous tc-99 m mdp uptake include extracellular fluid expansion , enhanced regional vascularity and permeability , diminished lymphatic or venous removal from the affected area , and elevated tissue calcium concentration .
tissue damage from inflammation , infection or physical trauma results in localized hyperemia , edema or calcium ( and hemosiderin ) deposition based on their pathophysiologic characteristics .
because of advent of spect ct , it is possible to localize exact site of tracer uptake and characterize the lesion to guide further management .
spect / ct localizing the uptake to the hematoma in the left brachialis muscle help in ruling out metastasis .
 we report a case of 79-year - old male with prostate cancer and coagulation disorder presented with left shoulder pain . 
 he underwent bone scintigraphy to rule out metastasis , which showed intense foci of tracer activity in the left axilla . 
 hybrid single - photon emission tomography - computed tomography ( spect / ct ) of the shoulder region localized tracer uptake to the left brachialis muscle hematoma . 
INTRODUCTION
CASE REPORT
DISCUSSION