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a 62-year - old man affected by lymphoma with known skeletal metastases , was referred to our department with symptoms of refractory pain after non - operative therapy , which included chemotherapy , local radiotherapy , and opioid treatment . a month prior to the referral , the patient was admitted for a vertebroplasty for the t12 , l1 , l2 and l3 due to severe low back pain .
the operation was significantly relieved from pain ; however , the lower back pain progressively returned over the course of a month .
after conferral with the orthopedic surgeon , discussion with the patient 's family , and consent from the patient , percutaneous sacroplasty treatment was decided upon to restore sacrum stability and resolve the pain caused by the mixed lesion .
prophylactic antibiotic therapy was performed by intravenous administration of 2 g of cefuroxime sodium ( livzon medical ltd , china ) , 30 minutes before commencing the procedure and was continued for 3 day after the procedure . before the procedure , a careful review of the radiology films and a measure of skin depth to the center of the lesion as well as the s1 marrow space from the dorsal to ventral cortex , were performed as specified by the trans - sacroiliac joint approach ( fig .
the lumbo - sacral junction was centered and the c - arm adjusted until the s1 foramen could be visualized .
next , a 13-gauge bevel - edge needle ( optimed medizinische instrumente gmbh , germany ) was introduced through the skin incision and subcutaneous tissue , to the periosteum of the bone , and then advanced to the center of the mixed lesion at the center of s1 transverse ilium , sacroiliac joint and sacrum ( fig .
we adjusted the cephalopod and left - right angle according to the sagittal and axial films of ct and mri until the needle attained the lesion under all fluoroscopy projections .
after removal the inner needle , a commercial polymethyl methacrylate ( pmma ) ( simplex p , stryker howmedica osteonics , east rutherford , nj ) was carefully injected carefully into the lesion under continuous fluoroscopic guidance in the lateral and ap projections ( fig .
1f , g ) to ensure the adequate filling of the lesion and avoidance of pmma leakage . a total of 6 ml of pmma was injected .
the post - procedural fluoroscopic findings showed optimal filling of the lesion with no evidence of pmma extravasation .
the patient experienced significant pain relief the next day and was able to ambulate without assistance .
the patient was discharged three days after the sacroplasty , following the completion of the prophylactic antibiotic therapy .
short - term ( within 2 weeks ) and middle - term ( within 3 months ) clinical follow - up were assessed by telephone .
a 38-year - old woman was admitted to the hospital due to severe low back pain as a result of a sacral metastatic tumor associated with lung cancer ( determined by a biopsy before the procedure ) .
both lumbo - sacral ct and mri examinations showed an osteolytic change at the s1 level .
the patient 's image results revealed a destroyed cortex margin and was deemed not to be suitable for sacroplasty ( fig .
however , the patient and her family strongly urged in favor of the operation , whatever the outcome . after obtaining informed consent , sacroplasty was performed under fluoroscopic guidance according to the technique described in case 1 .
the procedure was well tolerated without significant complication except for the cement deposition in the needle track ( fig .
unfortunately , no ct images were available to display the distribution of pmma to determine whether or not it leaked into neural foramina
. however , the patient experienced considerable pain relief with no complaints of nerve root compression following the procedure . a 20 week post - operative follow - up over the telephone found that the patient experienced little pain and continued to walk independently .
a 62-year - old man affected by lymphoma with known skeletal metastases , was referred to our department with symptoms of refractory pain after non - operative therapy , which included chemotherapy , local radiotherapy , and opioid treatment . a month prior to the referral , the patient was admitted for a vertebroplasty for the t12 , l1 , l2 and l3 due to severe low back pain .
the operation was significantly relieved from pain ; however , the lower back pain progressively returned over the course of a month .
after conferral with the orthopedic surgeon , discussion with the patient 's family , and consent from the patient , percutaneous sacroplasty treatment was decided upon to restore sacrum stability and resolve the pain caused by the mixed lesion .
prophylactic antibiotic therapy was performed by intravenous administration of 2 g of cefuroxime sodium ( livzon medical ltd , china ) , 30 minutes before commencing the procedure and was continued for 3 day after the procedure . before the procedure , a careful review of the radiology films and a measure of skin depth to the center of the lesion as well as the s1 marrow space from the dorsal to ventral cortex , were performed as specified by the trans - sacroiliac joint approach ( fig .
the lumbo - sacral junction was centered and the c - arm adjusted until the s1 foramen could be visualized .
next , a 13-gauge bevel - edge needle ( optimed medizinische instrumente gmbh , germany ) was introduced through the skin incision and subcutaneous tissue , to the periosteum of the bone , and then advanced to the center of the mixed lesion at the center of s1 transverse ilium , sacroiliac joint and sacrum ( fig .
we adjusted the cephalopod and left - right angle according to the sagittal and axial films of ct and mri until the needle attained the lesion under all fluoroscopy projections .
after removal the inner needle , a commercial polymethyl methacrylate ( pmma ) ( simplex p , stryker howmedica osteonics , east rutherford , nj ) was carefully injected carefully into the lesion under continuous fluoroscopic guidance in the lateral and ap projections ( fig .
1f , g ) to ensure the adequate filling of the lesion and avoidance of pmma leakage . a total of 6 ml of pmma was injected .
the post - procedural fluoroscopic findings showed optimal filling of the lesion with no evidence of pmma extravasation .
the patient experienced significant pain relief the next day and was able to ambulate without assistance .
the patient was discharged three days after the sacroplasty , following the completion of the prophylactic antibiotic therapy .
short - term ( within 2 weeks ) and middle - term ( within 3 months ) clinical follow - up were assessed by telephone .
a 38-year - old woman was admitted to the hospital due to severe low back pain as a result of a sacral metastatic tumor associated with lung cancer ( determined by a biopsy before the procedure ) .
both lumbo - sacral ct and mri examinations showed an osteolytic change at the s1 level .
the patient 's image results revealed a destroyed cortex margin and was deemed not to be suitable for sacroplasty ( fig .
2a , b ) . however , the patient and her family strongly urged in favor of the operation , whatever the outcome . after obtaining informed consent ,
the procedure was well tolerated without significant complication except for the cement deposition in the needle track ( fig .
unfortunately , no ct images were available to display the distribution of pmma to determine whether or not it leaked into neural foramina . however , the patient experienced considerable pain relief with no complaints of nerve root compression following the procedure .
a 20 week post - operative follow - up over the telephone found that the patient experienced little pain and continued to walk independently .
spinal metasatic tumors usually cause severe pain and immobility , requiring a high dose of opiates for pain relief ( 4 ) . currently , there is no ideal therapy available for the treatment of these lesions .
non - operative therapy for painful spinal metastasis includes bed rest , bracing , analgesia , radiotherapy , and chemotherapy , but the shortcoming of all these methods are that none can correct sacral instability .
surgical correction results in prolonged postoperative recovery time , with a high mortality rate 19% to 48% ( 5 , 6 ) , which is not a good option in patients with limited life expectancy .
osteoplasty is an effective palliative treatment for symptomatic spinal metastases , relieving pain and improving quality of life ( 7 , 8) .
the author 's two sacroplasty cases provided marked pain relief , improved daily living activity , and no significant complications , except for cement disposition in the needle track in the female patient .
the mechanism of pain relief in patients with metastatic lesions treated by cement injection is currently not well understood .
stabilization of the micro - fractures and the analgesic effect of pmma due to the thermal effect in itself seemed to be the main factors for short - term pain relief .
long - term pain relief will probably require volume reduction and necrosis of the tumor ( 9 , 10 ) .
although the percutaneous sacroplasty technique is similar to vertebroplasty , there are several technical considerations to deal with which are not encountered when performing a vertebroplasty .
notably , it was difficult to locate the needle tip because the curved ventral cortical margin of the sacrum was difficult to see .
another concern was the risk of cement migration and the compression of the sacral nerve roots and sacral spinal canal .
our two sacroplasties , performed entirely under fluoroscopic guidance , were successful ; however , we recognize that the exclusive use of fluoroscopic guidance is problematic due to the difficulty in visualizing the sacral foramina .
the visualization indicates whether the needle has adequately traversed the dorsal cortex and has not breached the ventral cortex , while also determining the distribution of pmma .
although we did not encounter any complications related to the needle puncture and cement extravasation , this technique remains has potential risks .
the ct - guided approach gives better definition of the spatial relationships within the treatment field , which aids in preventing patient injury to the nearby vascular , neurological , and visceral structures .
the ct also can provide more accurate imaging of complex fracture planes as well as enabling a higher level of precision in targeting the needle tip to the tumor .
the relative limitation of ct - guidance is the lack of real - time monitoring of cement delivery and quick detection of stray cement extravasation
. a combination of the ct and fluoroscopic guidance may be the best alternative at present , which has been accepted by many authors ( 1 , 3 ) .
( 2 ) suggest a ct - fluoroscopy suite might be the ideal setting to allow for both precise needle placement and real - time visualization of cement delivery . in conclusion , sacroplasties may be performed under fluoroscopic guidance only , although they are technically demanding and involve an increased risk of injury .
our success in performing the sacroplasties was attributed to performing 837 vertebroplasties over a six year period .
percutaneous sacroplasty is a safe and effective procedure for sacral insufficient fractures under ct or fluoroscopic guidance ; although , few reports exist about sacral metastatic tumors . we designed a pilot study to treat intractable pain caused by a sacral metastatic tumor with sacroplasty . a 62-year - old man and 
 a 38-year - old woman with medically intractable pain due to metastatic tumors of s1 from lymphoma and lung cancer , respectively , underwent percutaneous sacroplasty . 
 over the course of the follow - up period , the two patients experienced substantial and immediate pain relief that persisted over a 3-month and beyond . 
 the woman had deposition of pmma ( polymethyl methacrylate ) in the needle track , but did not experience significant symptoms . 
 no other peri - procedural complications were observed for either patient .