Imbibe Marrow Aspiration and Delivery - Surgical Techniques

Palpate and mark the anterior superior iliac spine (ASIS). To minimize the amount of tissue traversed by the BMA needle, retract any overhanging skin and subcutaneous fat and grasp the iliac crest between the thumb and fingers.

With a #11 or #15 scalpel, make a stab incision over the iliac crest at a point located 5-6cm posterolateral to the ASIS. The widest distance between the inner and outer tables of the anterior iliac crest is located in the region and best suited for bone marrow aspiration (BMA). Needle placement in this area will also avoid any potential injury to the lateral femoral cutaneous nerve which may traverse the iliac crest just proximal to the ASIS in the some individuals. (Fig 1)

Place the sharp-tip BMA needle through the stab incision. Use the needle tip to "palpate" the iliac crest and, once the center of the crest is located, seat the needle tip into the cortical bone with one or two brisk taps with a small, lightweight mallet (Fig 2). Using a mallet to advance the needle through bone is the preferred technique as it affords the surgeon greater control of the needle. Advancing the needle by hand often requires excessive downward force and, should the needle suddenly lose contact with bone, may result in perforation of the abdominal cavity and potential visceral injury. Advance the needle approximately 0.5 to 1.0cm through the cortical bone by tapping with the small mallet.

Angle the BMA needle approximately 35-40 degrees medial from the para-sagittal plane in line with the iliac wing as guaged by palpation. (Fig 3)

Exchange the sharp-tip trocar with the bullet-tip stylet. The bullet-tip stylet is designed to navigate between cortical bone boundries as the rounded tip will deflect the needle back into cancellous bone and minimize risk of cortical perforation.

Advance the needle to a depth of 2.0 to 2.5cm so that the aspiration holes are within bone. Remove the stylet and aspirate 2 to 4cc of marrow using a 10cc or 20cc syringe. Detach the syringe from the needle and replace the bullet-tip stylet.

Advance the needle an additional 2.0 to 2.5cm along the same trajectory and again aspirate 2 to 4cc of marrow. Additional marrow may be obtained using a "fan" technique. Withdraw the needle enough so that it can be redirected 25° cephalad or caudad, then advance the needle to a minimum depth of 2.0 to 2.5cm before aspirating again.

Palpate the posterior superior iliac spine (PSIS) and the prominence of the posterior iliac crest. The entry point for the BMA needle into the posterior iliac crest must be no more than 8cm from the PSIS to avoid injury to the cluneal nerves. (Fig 6)

With a #11 or #15 scalpel, make a stab incision at the desired location over the iliac crest and place the sharp tip BMA needle (Fig 7) through the stab incision down to bone. Use the needle tip to "palpate" the iliac crest and, once the center of the crest is located, seat the needle tip into the cortical bone with one or two brisk taps with a small, lightweight mallet. Using a mallet to advance the needle through bone is the preferred technique as it affords the surgeon greater control of the needle. Advancing the needle by hand often requires excessive downward force and, should the needle suddenly lose contact with bone, may result in perforation of the sacrum or gluteal muscle.

Initially angle the BMA needle roughly 40 degrees lateral from the para-sagittal plane and 35-40 degrees caudad. Advance the needle approximately 0.5 to 1.0cm through the cortical bone by tapping with the small mallet. (Fig 8)

Exchange the sharp-tip trocar with the bullet-tip stylet (Fig 9). The bullet-tip stylet is designed to navigate between cortical bone boundaries as the rounded tip will deflect the needle back into cancellous bone and minimize risk of cortical perforation. (Fig 10)

Advance the needle to a depth of 2.0 to 2.5cm so that the aspiration holes are within bone. Remove the stylet and aspirate 2 to 4cc of marrow using a 10cc or 20cc syringe (a 20cc syringe provides greater vacuum for marrow aspiration). Detach the syringe from the needle and replace the bullet-tip stylet.

Advance the needle an additional 2.0 to 2.5cm along the same trajectory and again aspirate 2 to 4cc of marrow. Additional marrow may be obtained using a "fan" technique. Withdraw the needle enough so that it can be redirected 25° caphalad or caudad, then advance the needle to a minimum depth of 2.0 to 2.5cm before aspirating again. (Fig 11)

The 8-gauge x 6" BMA needle may also be used for bone marrow harvest from the lumbar vertebral bodies via a transpedicular approach. (Fig 12)

The outside diameter of the BMA needle is 4.2mm, similar to most "gearshift" pedicle finder instruments. Using an open technique, the pedicle landmarks are identified and the outer cortex of the pedicle perforated using the surgeon's preferred technique. Prior to any tapping o the pedicle, the BMA needle with bullet-tip stylet is advanced slowly through the pedicle using a back and forth twisting motion. The needle should be advanced to a minimum depth of 2.0 to 2.5cm as judged by the graduated markings on the needle. Once positioned, remove the bullet-tip stylet and aspirate 2 to 4cc of bone marrow with a 10cc or 20cc syringe (a 20cc syringe provides greater vacuum for marrow aspiration).

If deemed appropriate by the operating surgeon, the needle can be advanced another 2cm into the vertebral body and additional bone marrow aspirated. The opposite pedicle of the same vertebra or the second vertebral pedicles can also be used for aspiration.

The pedicle can also be accessed using a percutaneuous approach with flouroscopic guidance. In this case, the BMA needle with a sharp-tip trocar would be utilized in the same fashion as a standard Jamshidi or targeting needle to access the pedicle. After aspiration of marrow from the vertebral body, a guide pin can be inserted if percutaneous spinal instrumentation is utilized.

With a #11 or #15 scalpel, make a stab incision at the desired location over the iliac crest and place the sharp tip BMA needle (Fig 7) through the stab incision down to bone. Use the needle tip to "palpate" the iliac crest and, once the center of the crest is located, seat the needle tip into the cortical bone with one or two brisk taps with a small, lightweight mallet. Using a mallet to advance the needle through bone is the preferred technique as it affords the surgeon greater control of the needle. Advancing the needle by hand often requires excessive downward force and, should the needle suddenly lose contact with bone, may result in perforation of the sacrum or gluteal muscle.