ABSTRACT ID: IRIA - 1061

Osteoid osteoma is a common entity with male
predilection, male to female ratio – 4:1

Most of the effected are young individuals in second
decade of life.

Dull aching deep bone pain - worsening in the nights,
relieved by analgesics.

On physical examination tenderness is present.

Signs of inflammation including erythema, warmth are
almost always absent
 The
treatment options available are Surgery and
Radio Frequency Ablation.
 Due
to the prolonged hospital stay, complications
and incomplete removal of the nidus leading to
recurrence; surgery is a less desired option.
 Radio
Frequency Ablation has proved to be
quick, safe and minimally invasive method of
management.

A 17 year old Indian male patient complaints of 8
months deep bone pain over left hip.

Pain was worsening at night with sleep disturbance,
aggravated on walking and relieved on rest.

H/o trauma 2 years back- slip and fall from height of
10 meters.

No H/o recent fever. No H/o pain over small joints or
early morning stiffness.

N/K/C/O DM/BA/TB/Jaundice
PALPATION:
INSPECTION:
 Scarpa triangle tenderness present.
 Muscle wasting was evident
over the thigh and calf regions.  Greater trochanter tenderness present.
 Scarpa triangle fullness is seen  No mass palpable.
in the left hip.
 Left anterior superior iliac
spine is inferior compared to
right side(pelvic tilt)
 No limb length discrepancy or
gluteal muscle wasting
 Flexion and internal rotation
movements of left hip joint were
restricted.
 Trendenlenburg test: Positive
 Femoral and distal pulses felt.
 Active toe movements present.
 Sensation intact.
 The
patient was then admitted and all the
baseline investigations were done.
 All
the baseline investigations were found to
be within normal limits.
 The
patient was then subjected for
Radiological investigations.
Image A : (Shows)
 Oval lytic lesion (nidus) at
the medial cortex of the left
femoral neck near the lesser
trochanter with surrounding
sclerosis and adjacent
cortical thickening.
 Nidus measured 2.0 x 1.2 cm
(Cc x Tr) with internal
calcific foci.
Image A
Oval lytic lesion (nidus) 2.0 x 1.2 cm at the medial cortex of the left femoral neck near the
lesser trochanter with surrounding sclerosis and adjacent cortical thickening.
 Radio
Frequency Ablation was planned after
radiological confirmation of the diagnosis of
Osteoid osteoma.
 Prothrombin
time and international normalized
ratio (INR) were tested and found within normal
limits.
 Anaesthetist’s
 Prophylactic
evaluation was carried out.
antibiotic (Cefotaxime 1 gm ) was
administered immediately before the procedure.
Lesion localization done with 128 multi detector row CT to confirm accurate needle position within the nidus.
 (Image on the (L): Scout image confirming the needle position with gonadal pads
 Image (R)Red arrow – Bone biopsy cannula. Yellow arrow – tip of the electrode)
 Under CT guidance and spinal anaesthesia, percutaneous entry into the osteoma nidus was made using
osteocyte bone biopsy cannula (13 G) with a drill and Kirchner wire.

Aspiration of the nidus content was done and sent for
histo pathological examination – diagnosis of osteoid
osteoma was confirmed.

Nidus was ablated in two locations(cranial and caudal)
by two bone tracts. Calories ablated were 1.27 Kcal
and 1.6 Kcal respectively for 5 minutes each.

Injection lignocaine 2 ml was injected into the nidus at
the end of the procedure.

The duration of the procedure was 120 minutes.
Image above shows needle tracts taken during Radio
Frequency Ablation(coronal).
Above images show needle tracts in various sections
The image above is a post procedural x ray showing
needle tracts.

The patient reported to have immense pain relief without any
analgesics the very next day.

Complaining of pain only at skin entry site.

Normal sleep in the night.

Patient was advised to avoid vigorous activities, sports such as
jumping long distance running for a month.

This was the first Radio frequency Ablation procedure done in
the Pondicherry territory.
 A follow
up X ray of pelvis was done after 30
days – needle tracts were evident.
 No
fresh complaints from the patient.
 Bone
 No
pain relieved.
other delayed complications were reported.
 The
post procedural period was uneventful
 An
Osteoid osteoma is a benign skeletal tumour
usually less than 1.5 cm in diameter.
 Composed
of woven bone and an osteoid and
more located in the appendicular bone.
 Focal
 Pain
pain at the tumour site.
worsens in the night and increases with
activity and is relieved with analgesics and
inflammatory medications.
 The
pain is presumed to be a result of local
vasodilatation resulting from elevated levels
of PGE2 at the site of the tumour.
 Spinal
osteoid osteoma may in addition lead to
scoliosis.
 These
tumours usually regress spontaneously ,
the mechanism probably being bone
infarction.

Difficulty in lesion localization, consequences of
extensive dissection and need for prolonged
recuperation and risk of incomplete removal and
therefore recurrence of the lesion make surgery a less
desired option.

Radio Frequency Ablation is proved to be safe, quick
and minimally invasive method of management.

We were able to achieve a high technical and clinical
success without any complications. Percutaneous
Radio Frequency Ablation should be the method of
choice for treating extra spinal osteoid osteoma.

Cartnell CP,O Byrne J , Eusrac 3 Radio frequency ablation of osteoid
osteoma with cooled probes and impedance control energy delivery, AJR
AM J Roentgenol 2006; 186 (5 suppl) S 244- S248 (cross ref J E
medicine)

Rosanthal DI, Marota JJA, Hornicok FJ osteoid osteoma :elevation of
respiratory and cardiac rates at the biopsy needle entry into the tumour in
10 patients, Radiology 2003,226: 125-128 (abstract medicine)

Resnik D, Kyariakos M, Guerdn D, Greenway bone and joint imaging, 3rd
ed, Elsevier Saunders;2005 Tumours and tumour like lesions of
bone:Imaging pathology of specific lesions;pp1121-98

Kitsoulis P , Mantellos G, Vlychou M, Osateoid osteoma,Acta Orthop
Belg.2006;72 119-25 (PubMed)

Solav SV, lack of hypervascularity on three phase bone scan:osteoid
osteoma revisited.World J Nucl Med. 2006;5:1