Collection of bone marrow (BM) is essential for the diagnosis of many haematological and neoplastic conditions. Collection of good quality BM is needed for accurate diagnosis, with BM aspiration enabling cytological analysis and core samples, histological assessment of BM architecture. A rotary battery-powered device (OnControl^TM, Vidacare Corporation, San Antonio, USA) has recently become available for the collection of BM in humans. This study aimed to investigate the use of this device in veterinary patients.

Between July 2010 and October 2011, BM was obtained from 15 patients; five using the 1.83 x 68 mm (15 gauge) OnControl^TM aspiration needle (2 cats, 3 dogs) and ten using the 2.3 x 102 mm (11 gauge) OnControl^TM biopsy needle (1 cat, 9 dogs). The indication for BM collection for all patients was possible BM disease [non-regenerative anaemia (7/15), lymphocytosis (2/15), hyperglobulinemia (2/15)].

Bone marrow collection was performed from the proximal humerus under general anaesthesia. All animals received pre-medication with methadone (0.1–0.25 mg/kg). The area was prepared aseptically and infiltrated with lignocaine. A stab incision was made and the needle inserted using the battery powered device. Once inserted, the stylet was removed and BM was aspirated using a 20 ml syringe; both needle and syringe were pre-coated with CPDA. For core biopsies the needle was inserted 2–3 cm further into the bone using the device and samples placed in formalin for analysis. Total procedural time was less than 5 minutes in all patients.

Aspirates were successfully collected from 14/15 cases. Eleven samples were of high diagnostic quality, with 3 samples being of poor quality. In cases where good quality aspirates couldn't be collected (2 with a core diagnosis of myelofibrosis, 1 dog with Leishmania and a dog with pure red cell aplasia) samples were repeated manually in the opposite humerus (4/4) and ileal wing (1/4); in no case was a better sample obtained.

Core samples were attempted and obtained in 10 patients. Cohesive cores were obtained from 8 patients, with friable partially fragmented cores from 2 patients with myelofibrosis. All samples were diagnostic. One sample contained a moderate crush artefact.

All animals were assessed using the Glasgow composite pain tool for 24 hours post procedure, no additional analgesia was needed. No complications were reported. In this group of patients the device was safe, easy to use and allowed rapid collection of good quality BM in the majority of cases.