Page 16 - HBC Booklet - 2020

1792 Eur Spine J (2011) 20:1791-1795

the market, but their application is associated with addi­ and 100 µg/ml Streptomycin (both Sigma-Aldrich,

tional costs and data on their effectiveness are still limited Vienna/ Austria) for transportation. Bone tissue was stored

[5]. Autograft bone chips harvested from the laminae and a t room temperature for a maximum of 24 h prior to tissue

spinous processes during decompression surgery are culture initiation.

widely used, but their availability can b e limited i n case o f

revision surgery or infection [ 4]. Tissue culture

Ekanayake and Shad [2] were the first to report the

suitability of bone dust derived from drilling the posterior Bone samples were washed twice in Phosphate Buffered

osteophyte as an autograft in anterior cervical fusion. Saline (PBS, Invitrogen Carlsbad/CA, USA) t o remove

Histological evaluation of those high speed burr shavings contaminating erythrocytes. After removal of a sample for

demonstrated that they are mainly composed of bone and histological evaluation, wet weight of the remaining tissue

blood products. The bone fraction contains viable osteo­ was assessed. Tissue harvested b y rongeur and drill was

2
blasts without obvious microscopic damage caused by the then placed in separate 10 cm tissue culture plates. DMEM

burring process [6]. Bone shavings derived from drilling supplemented with 10% fetal calf serum (FCS; Biomedica,

the lamina in order to get access to the intervertebral disc Vienna/Austria), 2 mM L-Glutamine (Invitrogen, Carlsbad/

space might therefore represent an additional source o f CA, USA), 0.05 mg/ml Ascorbic Acid (Sigma-Aldrich,

autograft bone for lumbar spinal fusion. This would also be Vienna/Austria), 100 U/ml Penicillin and 100 µg/ml

advantageous for minimal invasive surgery, where less Streptomycin was used as a culture medium. Culture plates

bone material can be acquired than via open techniques. were checked daily for osteoblast emigration and culture

Aim of the present study i s an in vitro comparison o f the viability. Culture medium was replaced twice a week.

osteogenic potential o f laminectomy bone chips conven­

tionally obtained by a kerrington rongeur and bone shav­ Histological evaluation

ings harvested using a high speed burr equipped with a

suction trap. Samples of bone tissue harvested either b y kerrington

rongeur or high speed drill were fixed in 4% formaldehyde

(institutional pharmacy) for 4 8 h , followed b y decalcifi­

®
Materials and methods cation in Osteosoft (VWRNienna, Austria) and paraffin

embedding. 5 µ m sections were prepared and stained

Sample harvesting Haemalaun/Eosin according t o Romeis and Boeck [7].

Histological slides were analyzed using an Olympus IX-71

Bone samples from 14 patients (13 female, 1 male) under­ nncroscope.

going lumbar spinal surgery (decompression with/without Passage 1 osteoblast emigration cultures o f both study

fusion) were analyzed in the laboratory. Patients' ages were groups were harvested via Trypsin-EDT A detachment as

between 50 and 81 years (mean age 68 years). All patients described below. Cells were seeded on four well-cham­

showed a normal or slightly increased body weight (mean bered slides (Sigma-Aldrich, Vienna/Austria) and cultured

BMI 25.4) and no history of nicotine abuse o r metabolic to subconfluency. Slides were then rinsed in PBS and fixed

disease. Two patients had a record of cortisol treatment and in methanol (VWRNienna, Austria) for 10 min at room

three patients suffered from manifest osteoporosis. temperature, followed by rinsing in distilled water and

The study was approved by the institutional ethics Alizarin red staining to detect Calcium deposition indi­

board. Bone samples were harvested from the laminae and cating mineralization. Alizarin red staining protocol was

the spinous processes during routine spinal decompression. obtained from Histoweb [8].

Bone harvest from each patient was performed both as

bone chips using a kerrington rongeur and via high speed Evaluation of osteoblast emigration

drill (Ortho-TPS/Stryker) resulting in tiny bone shavings.

Bone tissue was chilled using saline solution during the Osteoblast emigration from the source tissue was checked

drilling process and collected using an in-line suction trap o n a daily basis and the attachment o f the first osteoblast t o

(B-collector/Intramed). After completion of cage and the culture dish was noted. As soon a s all tissue samples of

intervertebral space preparation, the remaining bone chips a study group demonstrated osteoblast emigration (which

a s well as the bone shavings were aseptically sent to the was referred to as a 100% emigration rate), the emigration

cell culture laboratory. Samples were placed separate! y in rate o f the corresponding bone sample was determined.

sterile falcon tubes pre-filled with Dulbecco's Modified Cells were then allowed to emigrate from the source tissue

Eagle's Medium (DMEM high glucose; Biomedica, and allowed to multiply for 3 weeks in vitro. After that

Vienna/Austria) supplemented with 100 U/ml Penicillin period, source tissue was removed and the osteoblasts were

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