.Redirect the needle tip and rotate it 360 degrees in both directions to separa ate the biopsy specimen from the Following this step.the needle should be advanced a very short distance prior to removal.This step may prevent the specimen from being pulled out of the needle at the biopsy site -Remove the needle with a sliahttwistina motion place a sterile dressina ove the site,and apply pressure for se stops.Once stasis is achie eved,a bandage should be applied,and the patientshould be instructed to lie supine for 10 or more minutes. Pressure dressings may be required in thrombocytopenic patients. .Once the biopsy needle has been removed.the specimen may be extracted from the needle by inserting the obturator(or stylet)through the distal(cutti end of the needle The bone ma row biopsy can then be placed on a slide,where imprints("touch prints")are made before the core specimen is further processed for cytologic investigations.This step is especially useful in situations where a bone marrow aspirate could not be obtained (see The dry tap'below)131 Examine the biopsy sp en.If the onsists mostly of us.wr 0nsenaileotcasneorg ing tissu (cartilage).it may be necessary to attempt a second biopsy for a more satisfactory specimen.This should be done with a new biopsy needle,as the original needle may have been damaged by the process of inserting he e obturator or stylet through the distal end of the biopsy needle. .Prior to leaving the patient,the bone marro aspiratio /b psy site(s) should be evaluated to assess for prolonged bleeding.This is minimized by applying a pressure dressing over the site(s).with the patient remaining recumbent,for at least 10 minutes. Anterior iliac crest- Samples are taken from a site 2.5 to 5 cm posterior the anterior superior iliac spine and beneath the palpable lip of the iliac crest (fiqure 2)[411. .The patient should be relaxed,comfortable,and in the supine position .Once a satis ory site has been identified,the rem nder of the procedure is identical to that for the postenor iliac crest.(See 'Posterior iliac crest'above.) Sternal aspiration -This procedure should only be undertaken in patients more than 12 years old.Select a level of the stemum at eitherthe second or third intercostal space(fiqure 3)[14].Aspiration should be attempted only from the first part of the body of the stemnum,or from the manubrium [4]. .The patient should be positioned in a semi-recumbent or supine positior tion needle fu ctions properly and that t the guard is securely in place.The quard should be adjusted so that only 5 mm advancement of the needle is possible beyond the periosteum [42].●Redirect the needle tip and rotate it 360 degrees in both directions to separate the biopsy specimen from the surrounding marrow tissue. Following this step, the needle should be advanced a very short distance prior to removal. This step may prevent the specimen from being pulled out of the needle at the biopsy site. ●Remove the needle with a slight twisting motion, place a sterile dressing over the site, and apply pressure for several minutes until the bleeding stops. Once hemostasis is achieved, a bandage should be applied, and the patient should be instructed to lie supine for 10 or more minutes. Pressure dressings may be required in thrombocytopenic patients. ●Once the biopsy needle has been removed, the specimen may be extracted from the needle by inserting the obturator (or stylet) through the distal (cutting) end of the needle. The bone marrow biopsy can then be placed on a slide, where imprints ("touch prints") are made before the core specimen is further processed for cytologic investigations. This step is especially useful in situations where a bone marrow aspirate could not be obtained (see 'The dry tap' below) [3]. ●Examine the biopsy specimen. If the specimen consists mostly of homogeneous, white material (cortical bone) or glistening tissue (cartilage), it may be necessary to attempt a second biopsy for a more satisfactory specimen. This should be done with a new biopsy needle, as the original needle may have been damaged by the process of inserting the obturator or stylet through the distal end of the biopsy needle. ●Prior to leaving the patient, the bone marrow aspiration/biopsy site(s) should be evaluated to assess for prolonged bleeding. This is minimized by applying a pressure dressing over the site(s), with the patient remaining recumbent, for at least 10 minutes. Anterior iliac crest — Samples are taken from a site 2.5 to 5 cm posterior the anterior superior iliac spine and beneath the palpable lip of the iliac crest (figure 2) [41]. ●The patient should be relaxed, comfortable, and in the supine position. ●Once a satisfactory site has been identified, the remainder of the procedure is identical to that for the posterior iliac crest. (See 'Posterior iliac crest' above.) Sternal aspiration — This procedure should only be undertaken in patients more than 12 years old. Select a level of the sternum at either the second or third intercostal space (figure 3) [14]. Aspiration should be attempted only from the first part of the body of the sternum, or from the manubrium [4]. ●The patient should be positioned in a semi-recumbent or supine position ●Ensure that the aspiration needle functions properly and that the guard is securely in place. The guard should be adjusted so that only 5 mm advancement of the needle is possible beyond the periosteum [42]