bone marrow evaluation is essential in the diagnostic evaluation of both hematopoietic and many non - hematopoietic disorders , determining the efficacy of treatment and to monitor the recovery process in patients undergoing bone marrow transplantation or marrow - ablative chemotherapy and is also part of the staging process for newly diagnosed patients with lymphoproliferative diseases and certain non - hematopoietic malignancies .
regardless of the diagnostic value of the biopsy procedure , the pain experienced during and after the procedure makes some patients fear the procedure and/or reluctant to undergo follow - up biopsies . attempting to mitigate the procedural pain and discomfort , some providers elect to use conscious sedation during the bone marrow procedures ; but this may expose the patient to additional physical risks , increased liability to the provider , and a requirement for increased patient monitoring during and after the procedure . since 1971 the jamshidi needle has been the device of choice for bone marrow sampling with no substantial advancement in marrow sampling technology thereafter .
biopsy procedures facilitated by drill - powered needles have been attempted , but with mixed results . in 1993 ,
ahlstrom and astrom described a 32-patient study in which a makeshift bone biopsy system , that included a power drill , was used to obtain the bone marrow sample .
more recently , buckley et al . describe a 68 patient study in which patients underwent bone biopsy using a black and decker drill to access the iliac crest .
oncontrol is a battery - powered bone marrow biopsy system ( vidacare corporation , shavano park , tx , usa ) which allows operators to quickly and efficiently obtain both bone marrow core and aspirate ( figure 1 ) .
we recently reported the preclinical comparison of the oncontrol to manual biopsy in swine together with an uncontrolled prospective clinical evaluation for outpatient bone marrow aspiration and biopsy .
these findings suggested that the powered system was able to produce specimens of equal or greater quality faster and in a more efficient manner .
while prospective analysis has shown a strong correlation between the duration of the procedure and the morbidity - particularly with respect to patient discomfort , there has not yet been a clinical study published comparing the new powered device to traditional manual bone marrow biopsy needles .
we report on this study designed to comparatively determine if the powered core biopsy needle has advantages over traditional manual needles in terms of improved bone marrow sample yield , decreased pain , and procedure time . 

the power driver and biopsy needle components of the oncontrol powered bone marrow sampling system . the powered bone marrow biopsy system .
the power driver and biopsy needle components of the oncontrol powered bone marrow sampling system .
this single - center , randomized , controlled trial was approved by integreview institutional review board , performed in accordance with the declaration of helsinki and good clinical practice , and conducted in a community - based cancer clinic . after obtaining informed consent , a medical history and demographics
were recorded ; followed by complete blood count analysis ( cbc ) and a physical examination .
each subject , serving as his / her own control , received bone marrow biopsy procedures using powered and manual devices .
the powered device was the oncontrol bone marrow biopsy system ( vidacare corporation ) , an fda - cleared device consisting of a battery - powered driver and biopsy needle set .
the driver resembles a small hand - held drill , and powers a single lumen needle set into the medullary cavity of the adult iliac crest .
the needle set consists of two parts : an outer cannula , 11 gauge by 4 inches ( 102 mm ) long ; and a bevel - tip inner stylet - used to penetrate the cortex .
richmond , va ) bone marrow biopsy needle ( 11 gauge by 4 inches ) , which has a two - piece t - handle design , a trocar - tapered stylet point and a triple crown cannula tip .
two operators ( one private practice and one academic hematologist / oncologist ) , experienced in the use of both devices , performed the bone marrow procedures using the posterior iliac crest .
the order in which the devices were used on the subject , and which side was biopsied first ( right or left ) was randomized .
there was minimal time between the two biopsy procedures ; just enough for the physicians to reposition after the first procedure .
five to 7 ml of 1% lidocaine buffered with sodium bicarbonate was injected intradermally , subcutaneously and periosteally as a local anesthetic for each biopsy procedure . to assure that the subjects were not biased towards one type of biopsy needle over the other , they were carefully screened and oriented .
they were told that the purpose of the trial was to see if there was a difference in the intensity of pain experienced between the two types of needles .
they did not know , nor were they told , if either of the needle types was preferred by the investigators . to minimize the noise caused by the powered device , and to decrease the potential for the noise to compromise the blinding of procedure order , noise - cancelling headphones were placed on the subjects during each procedure . to further ensure that noise was not a clue for the subject ,
the time , in seconds , from contact of the needle with skin to sample acquisition was recorded .
pain was measured for intensity using a 100 mm visual analog scale ( vas ) , with scores ranging from 0 to 100 , and higher scores indicating more pain .
participants indicated their pain level by placing a mark on a 100 mm line at the instant of cortical penetration , biopsy core acquisition , and needle removal .
it was recognized that since these volunteers had never experienced bone marrow sampling procedures , the pain scores for the first procedure might be skewed .
therefore , following the second procedure , subjects were given the opportunity to change the overall pain score indicated for the first procedure .
vas pain scores were also recorded 30 minutes , 24 hours and 48 hours after the procedure .
subjects were also queried concerning complications at those time points , with a final complication evaluation at 7 days post procedure . immediately following the procedures ,
core biopsy samples were measured and submitted to a blinded pathologist for quantitative and qualitative analysis .
one subject was disqualified because the biopsy needle insertions sites were not adequately anesthetized before the start of procedures , and the subject did not inform investigators of the inadequacy until biopsy procedures were completed .
the subject subsequently experienced severe pain bilaterally and required multiple doses of narcotic analgesia and repeated visits to medical facilities for pain relief .
another subject was obese and , after subcutaneous insertion , the first needle was not long enough to penetrate the iliac crest cortex to complete the procedure .
the decision was made to not make a second attempt and the subject was disqualified .
of the 24 evaluable subjects , there were 24 manual insertions and 24 powered insertions .
for those insertions , biopsy core samples were obtained in 66.7% of the manual insertions and 100% of powered insertions - a significant difference ( p=0.002 ) . the mean time to
core acquisition was 85.7 seconds for manual device and 46.5 seconds for the powered device , a significant difference ( p<0.001 ) . using the second look overall pain score ( for those that opted to change their score ) , the mean score for the manual device was 33.3 and 20.9 for the powered - a significant difference ( p=0.039 ) .
there was no statistical or clinical difference in other pain scores between the two devices .
the initial mean biopsy core length was 11.14.5 mm for the manual device and 17.06.8 mm for the powered device ; a statistical difference ( p<0.005 ) .
after fixation and processing , pathology assessment for the manual device showed a mean length of 6.15.6 mm , width of 1.00.7 mm , and volume of 11.010.8 mm .
measurements for the powered device were mean length of 15.36.1 mm , width of 2.00.3 mm , and volume of 49.121.5 mm .
for overall quality , 33.3% of manual samples and 79.2% of powered samples were graded adequate - a statistical difference ( p=0.002 ) .
results are compared with regard to device used for the procedure.variablemanualpoweredp(n=24)(n=24)successful core acquisition , first attempt ( % ) 66.7100.00.002*mean time to core acquisition ( seconds)85.731.046.515.80.000*mean biopsy core length ( mm ) per acquired specimen11.14.517.06.80.004*mean vas needle insertion ( 0100)28.924.420.517.30.177mean vas biopsy acquisition ( 0100)36.820.938.018.30.134mean vas needle removal ( 0100)28.826.627.021.00.792mean vas overall ( 0100)36.124.423.916.90.051mean vas overall after 2 look adjustment ( 0100)33.323.920.915.60.039*mean vas 30 minutes post procedure ( 0100)7.311.44.48.50.328mean vas 24 hours post procedure ( 0100)5.88.59.113.80.325mean vas 48 hours post procedure ( 0100)1.21.93.48.00.201pathology biopsy core length ( mm)6.15.615.36.1<0.001*pathology biopsy core width ( mm)1.00.72.00.3<0.001*pathology biopsy core volume ( mm)11.010.849.121.5<0.001*pathology - graded adequate biopsy core ( % ) 33.379.20.002**denotes statistical significance;vas , visual analog scale . denotes statistical significance ; vas , visual analog scale . between operators
, there was a difference for mean time to core acquisition ( 75.5 seconds vs 48.4 seconds , p=0.003 ) , mean biopsy core length ( 16.7 mm vs 12.0 mm , p=0.027 ) , and mean needle insertion vas ( 19.4 vs 33.6 , p=0.024 ) . between operators
, there was no statistical difference in other vas pain scores , ability to capture a core specimen or proportion of core biopsy specimens graded adequate by pathology ( see table 2 ) . 

results are compared with regard to operator performing the procedure.variableoperator aoperator bp(n=30)(n=20)successful core acquisition , first attempt ( % ) 76.794.40.113mean time to core acquisition ( seconds)75.533.248.417.60.003*mean biopsy core length ( mm ) per acquired specimen16.66.912.05.20.027*mean vas needle insertion both needles ( 0100)19.417.433.624.70.024*mean vas biopsy acquisition both needles ( 0100)28.618.938.720.60.090mean vas needle removal both needles ( 0100)26.323.530.624.70.550mean vas overall both needles ( 0100)24.820.134.022.50.327mean vas overall after 2nd look adjustment both needles ( 0100)27.621.230.922.30.332mean vas 30 minutes post procedure both needles ( 0100)5.39.96.810.60.607mean vas 24 hours post procedure both needles ( 0100)9.012.85.08.90.247mean vas 48 hours post procedure both needles ( 0100)2.67.21.82.60.641pathology biopsy core length ( mm)11.08.110.26.30.711pathology biopsy core width ( mm)1.40.81.70.60.187pathology biopsy core volume ( mm)31.527.827.721.80.629pathology - graded adequate biopsy core ( % ) 60.050.00.104*denotes statistical significance;vas , visual analog scale . denotes statistical significance ; vas , visual analog scale .
the only complication noted during the study was intense and extended pain experienced by one subject , which took nearly 4 weeks to subside .
in a 2009 article describing a 48-patient study that assessed pain during biopsy procedures , ruegg and associates reported mean biopsy needle insertion pain to be 38.5 when patients were anesthetized with buffered lidocaine . in our study , in which buffered lidocaine was also used , subjects rated their pain at 38.0 on average with the powered device . when given the opportunity to change the score for the first procedure , the mean pain score for the powered insertions was reduced to 20.9 .
the procedure time ( needle - to - skin contact to core biopsy sample acquisition ) was substantially shorter when using the powered device .
indeed , in kuball s 2004 publication describing 263 patients undergoing bone marrow procedures , investigators reported that the duration of the procedure , which averaged 7 minutes , was identified as the sole independent predictive factor for patients pain intensity .
the investigators did not define how the duration of needle insertion was measured , but the finding was quantitatively and qualitatively substantiated in our study .
this was particularly true for patients with harder bones in which more time and effort is required for cortical penetration . in our study , 154 seconds were required for one subject using the manual needle , compared to 70 seconds using the powered device .
for this subject , the manual procedure resulted in a bent needle ( figure 2 ) and no biopsy core sample . 

this shows the condition of the manual needle following insertion into a patient with hard bones .
this shows the condition of the manual needle following insertion into a patient with hard bones .
while clinicians strive to conduct bone marrow sampling procedures with as little pain and discomfort to the patient as possible , the ultimate goal of the procedure is the acquisition of a specimen suitable for diagnosis by pathologists .
inadequate specimens have a significant impact on clinicians ability to treat patients whose treatment depend an accurate diagnosis . in a 767 patient study ,
bishop et al . reported that only 42% of their biopsy specimens were adequate for accurate diagnosis .
an adequate sample must be of sufficient size and relatively free of crush artifact and trabecular distortion .
the superior core specimens acquired using the powered device is the key finding of this study . aside from a 100% first attempt core capture rate compared to 67% for the manual device , the powered device delivered core specimens that were 53% longer , and contained 346% more volume ( figure 3 ) . 

these are typical examples of bone marrow core specimens obtained following bilateral bone marrow biopsy procedures .
these are typical examples of bone marrow core specimens obtained following bilateral bone marrow biopsy procedures .
a limitation of our study was the use of healthy volunteer subjects , rather than actual patients .
we found it would be difficult and time - consuming for clinicians to accrue a satisfactory number of patients requiring bi - lateral procedures .
a second reason is because pain as a study outcome is generally problematic in actual patients due to the great amount of variability , bias and subjectivity .
these confounding factors are multiplied with cancer patients who often have underlying pain and an altered perception of pain .
another limitation was the decision not to collect a bone marrow aspirate - a normal component of bone marrow sampling procedures . for many patients ,
the negative pressure within the medullary space during the syringe aspiration causes the worst pain of the procedure , and the intensity of pain is not a function of needle - type . for this reason
one other limitation was our failure to standardize the amount of time between the local anesthetic infiltration and the biopsy procedure .
an additional limitation was failure to capture total pain ( e.g. intensity of the pain times the duration of the pain ) .
while the difference in the intensity of the pain did not reach statistical significance in several of the parameters tested , there is little doubt that the duration of the pain was substantially longer in the manual arm of the study .
several subjects stated that they would much rather have the powered needle because the procedure was faster .
results suggest the superior size and overall quality of core specimens delivered by the powered device provide more material for pathological evaluation of hematopoietic and oncological disorders .
the capture rate in obtaining a satisfactory sample on first attempt was much higher with the powered device , negating the necessity of conducting a second biopsy . while the powered bone marrow biopsy showed a trend toward decreased pain overall at the time of the procedures , use of the powered bone marrow biopsy device
 bone marrow sampling remains essential in the evaluation of hematopoietic and many non - hematopoietic disorders . 
 one common limitation to these procedures is the discomfort experienced by patients . to address 
 whether a powered biopsy system could reduce discomfort while providing equivalent or better results , we performed a randomized trial in adult volunteers . 
 twenty - six subjects underwent bilateral biopsies with each device . 
 core samples were obtained in 66.7% of manual insertions ; 100% of powered insertions ( p=0.002 ) . 
 initial mean biopsy core lengths were 11.14.5 mm for the manual device ; 17.06.8 mm for the powered device ( p<0.005 ) . 
 pathology assessment for the manual device showed a mean length of 6.15.6 mm , width of 1.00.7 mm , and volume of 11.010.8 mm3 . 
 powered device measurements were mean length of 15.36.1 mm , width of 2.00.3 mm , and volume of 49.121.5 mm3 ( p<0.001 ) . the mean time to core ejection was 86 seconds for manual device ; 47 seconds for the powered device ( p<0.001 ) . 
 the mean second look overall pain score was 33.3 for the manual device ; 20.9 for the powered ( p=0.039 ) . 
 we conclude that the powered biopsy device produces superior sized specimens , with less overall pain , in less time . 
Introduction
Materials and Methods
Results
Discussion
Conclusions