Osteoid osteomas are benign, painful osteogenic tumors
of small size (<2 cm) with limited or no growth potential.1-5 In
1930, Bergstrand first described osteoid osteomas and in 1935 Jaffe6
differentiated this entity from other variants. Grossly, they are composed of a
small “nidus,” measuring from a few millimeters to 1.5 to 2 cm, which
exhibits various portions of calcification and is surrounded by reactive
sclerosis and periosteal reaction.2,5,7,8 Osteoid osteomas are
relatively common bone lesions accounting for approximately 10% to 12% of all
benign bone tumors and 2% to 3% of all primary bone tumors.1,9,10
Young men in the first 3 decades of life are most commonly affected (5-25
years; 75% of cases).11,12 Typically, they are located in the
subperiosteal region of the diaphysis of the proximal femur and tibia (>50%
of cases).11 Generally, it is speculated that all long bone osteoid
osteomas grow subperiostealy and through constant bone remodeling, they finally
drift into more endosteal positions.8
Despite their predilection for the appendicular
skeleton, osteoid osteomas may be encountered in any other bone. Ten percent to
25% of all cases occur in the spine, especially in the posterior vertebral
elements (70%-100%) and less commonly in the vertebral body.13
Additionally, 13% of osteoid osteomas grow intra-articularly, usually within
the hip joint.8 In long tubular bones, besides diaphyseal location,
they can sit in the epiphysis or metaphysis as well, involving not only the
cortex but also the medulla and subperiosteal regions.7,11
Long-term medical treatment is not always well-tolerated
and adequately effective especially in cases where the lesion is located
intra-articularly or peri-articularly.7,8 Patient relief from
intense pain necessitates the removal or destruction of the nidus. Although
surgical resection of osteoid osteomas has been well-established for many
years,14-18 certain drawbacks such as poor lesion localization,
extensive tissue damage, and delayed recovery have encouraged the evolvement of
other less invasive percutaneous techniques. Computed tomography (CT)-guided
core-drill excision with or without ethanol injection,19-28
arthroscopic removal,29 cryoablation,30 and
thermoablation by laser31-36 or radiofrequency
energy5,10,12,36-53 have emerged as effective and minimally invasive
alternatives to overcome difficulties and potential hazards and avoid the
overuse of health care resources.
This article summarizes data concerning the
characteristics and behavior of osteoid osteomas and evaluates all standardized
and contemporary fashions of management.
Natural Course-Clinical findings
Figure: Histopathologic features of osteoid osteoma. Nidus displaying well mineralized trabeculae of woven bone (asterisk) lined by numerous active osteoblasts (arrow). In addition, multinucleated giant cell-like osteoclasts can be recognized (arrowhead).
Little is known about the natural history of osteoid
osteomas. These tumors are self-limiting and exhibit little or no growth
potential. Rarely, malignant transformation into aggressive osteoblastomas has
been reported.54 Nonetheless, cases of spontaneous healing after a
3- to 7-year period have also been observed.55,56
The clinical presentation of osteoid osteomas usually
consists of nonspecific findings, which in many instances confuse the physician
and result in delayed diagnosis. The mean duration of symptoms prior to
presentation is 16 months.16 In typical cases, the clinical hallmark
is local and intense pain of sudden onset, not related to prior exercise or
trauma, presenting nocturnal aggravation. Pain responds to the administration
of salicylates and other nonsteroidal anti-inflammatory drugs. Furthermore,
elevated skin temperature, local rubor, and tenderness may be observed in
superficial lesions.50 Patients with long-standing pain usually end
up with limping and related muscle atrophy.7 Other possible symptoms
vary according to tumor location and include bone widening and growth
disturbances or even angular deformities, when it rises near an open growth
plate.5,7,50 Spinal lesions may cause painful scoliosis or painful
torticollis.7 If located within a joint, tenderness, soft tissue
swelling, synovitis with restriction of movement, and contracture are commonly
The aforementioned clinical setting combined with
appropriate radiologic and scintigraphic features should raise a substantially
high index of suspicion.
Osteoid osteomas were first described in 1935 by
Jaffe57 as independent benign neoplasms, distinct from inflammatory
processes occurring in bone. They are small-sized bone-forming tumors, with
limited growth potential, primarily located within the cortex. Histologically,
these lesions consist of a central area of vascularized connective tissue,
nidus, that is largely occupied by active, differentiated osteoblasts that
produce osteoid or bone. Multinucleated osteoclast can also be encountered as
part of active bone remodeling (Figure). Cartilage, bone marrow elements, and
mitotic figures are usually absent.58,59 The nidus is characterized
by more abundant mineralization centrally (reflecting a central sclerosis on
radiographs) and separation from host bone by a fibrovascular core that is
located in the periphery of the sclerotic bone. It is usually surrounded by a
distinct zone of reactive sclerotic bone that is not an integral component of
the tumor, since it represents a secondary reversible change induced by the
exerted pressure of the highly vascular neoplastic tissue on the surrounding
trabeculae bone.55 The nidus is usually <1 cm in its greatest
diameter. Lesions measuring >2 cm should raise the possibility of
The pathogenesis of osteoid osteomas remains elusive.
Several in vivo and in vitro studies have demonstrated the presence of high
levels of prostaglandin E2 and prostacycline directly in nidus tissue, causing
local inflammation and vasodilatation. These mediators are considered
responsible for reactive sclerosis, nonspecific soft tissue reactive changes
and pain that occur in osteoid osteomas. In parallel, the stimulation of
unmyelinated neurofibers, accompanying the vessels in the nidus and the
surrounding reactive zone, has been also thought to play a significant role in
the mediation of pain.7,55,59-61
Its self-limiting course along with the report of
sporadic cases of spontaneous remission represents another clinical feature
needing interpretation. It is suggested that like other benign vascular osseous
lesions, such as benign bone angiomas, spontaneous thrombosis of the contained
blood vessels of osteoid osteomas may be a possible
On plain radiographs, the osteoid osteomas
“nidus” is typically depicted as an oval or round radiolucent area of
approximately 1 cm, surrounded by dense radio-opaque osteosclerosis or
periosteal reaction. The amount of the reactive bone may vary from subtle to
considerably dense completely obscuring the visualization of the
“nidus.”7 Intramedullary lesions, which account for 20% of
cases, do not present with prominent reactive sclerosis.11,55 In
addition, when the “nidus” is <3 mm it cannot be easily
demonstrated.8 In 15% of cases, the “nidus” may be
overlooked on radiographs.11 Occasionally, the radiolucent nidus may
contain various portions of mineralization, appearing as areas of radiodensity
on plain radiographs, hence resulting in the formation of the “Jaffe
sequestrum.”6 This calcification is associated with the
maturity of the tumor and becomes more prominent with age.8,55 Owing
to the lack of periosteum, intra-articular lesions are not associated with
periosteal reaction, which usually occurs in adjacent bones along with regional
Thin-section CT scan (≤2 to 3 mm), adequately
reconstructed with a bony algorithm is the ideal imaging modality for
delineating a small nidus, especially in the spinal pedicles, laminae, and
femoral neck or when intense reactive sclerosis and accompanying periosteal
reaction may obscure the lesion. Additionally, dynamic contrast-enhanced CT
greatly assists in differentiating osteoid osteomas from chronic osteomyelitis
by exhibiting the intense nidus enhancement in contrast with the relatively
avascular Brodie’s abscess.5,11 Other differentials include
osteoblastomas, stress fractures, arthritis, etc. In intra-articular lesions,
osteophytes, muscle atrophy, local osteopenia, and sclerosis on both sides of
the joint may be seen.8 Computed tomography scan can be also used as
an excellent guidance modality while performing percutaneous therapeutic
interventions.7 Osteoid osteomas in cancellous bone and joints are
often difficult to diagnose by CT alone owing to the lack of perinidal
On magnetic resonance imaging (MRI), the nidus appears
with variable signal intensity depending on size, age vascularity, and the
portion of mineralization contained.8 Most commonly, it is
demonstrated as isointense to the muscle on T1-weighted sequences while on
T2-weighted and STIR sequences its signal intensity varies from hypointense to
hyperintense or exhibits marked heterogeneity.63 Long-standing
lesions may form, with time, low-signal intensity on all pulse
sequences.64 Gadolinium-enhancement is more prominent in cases of
osteoid osteomas with less mineralization, especially on T1-weighted fat
suppressed sequences.65 Although MRI can identify cancellous osteoid
osteomas better than other techniques because of the lack of perinidal
alterations, in total, compared with CT, MRI is inferior in demonstrating the
nidus and may easily lead to nondiagnostic results.61,65,66 Assoun
et al66 comparing the conspicuity of CT and MRI in 19 patients with
osteoid osteomas, failed to recognize the lesion in 26% of cases (5/19) with an
overall potential for misdiagnosis of 63% (12/19). Accordingly, Davies et
al63 recently reported a 35% (15/43) potential for misdiagnosing
osteoid osteomas solely with MRI.
However MRI is sensitive in depicting useful but still
nonspecific characteristics of the tumor such as bone marrow and soft tissue
edema (64% and 47%, respectively).11 These reactions usually subside
following medical therapy and relate strongly with the maturity of the lesion;
detecting more edema in newer lesions and less in older lesions.8
However, these nondiagnostic features can, not infrequently, result in
diagnosing more aggressive osseous pathologies such as malignancies or
infections and stress fractures, jeopardizing thus the therapeutic
outcome.11,67 For all the above reasons, a consensus has been
established supporting that radiologists should take into consideration the
variation of appearances of osteoid osteomas and correlate the whole clinical
and radiologic setting (radiographs, scintigraphy, and CT scans) with the MRI
findings before making a diagnosis. When the suspicion of dealing with an
osteoid osteomas is considerably high, the MRI can then be used to localize
rather than characterize the nature of the lesion, provided that extra caution
is taken regarding the MRI technique performed.63
The latest comparative retrospective study of Liu et
al67 supported that, in contrast to unenhanced MRI, dynamic
gadolinium-enhanced MRI increases the conspicuity in detecting osteoid osteomas
and assists greatly in their accurate localization to an equal or even better
degree than thin-section CT. Furthermore, Cioni et al45 highlighted
the usefulness of dynamic contrast-enhanced MRI in detecting residual nidi
contrast uptake and persisting marrow edema during the follow-up of post
radiofrequency ablation patients with persistent or recurrent pain indicating
the need for an additional percutaneous intervention. In the future, open MRI
may facilitate, as an effective guiding system, the real-time monitoring of
tissue response during radiofrequency ablation while providing extra space for
technical maneuvering, with no ionizing irradiation.45
Bone scintigraphy is usually positive by showing
increased uptake of technetium-99m phosphonates at the tumor site. This intense
activity is maintained both at immediate and delayed acquisitions and is
usually defined as the “double density sign” composed of a small
focus of uptake, representing the nidus, superimposed on a larger area of
radioactivity peripherally indicating the reactive
sclerosis.2,5,7,8,12,50 A bone scan can exhibit radioactivity at the
lesion site before radiographic abnormalities become evident. Furthermore it
can provide the physician with useful information in patients with painful
scoliosis. Although, scintigraphy is sensitive, a negative bone scan does not
exclude the diagnosis of an osteoid osteoma especially in the presence of
highly suggestive clinical and CT findings.51 In the past, nuclear
medicine was used to confirm intraoperatively the complete eradication of the
nidus; however currently, along with radiographs, CT and MRI scans are useful,
especially in cases with subtle appearance.7,11
Owing to the self-limited nature of osteoid osteomas and
their potential of resolving spontaneously after several years, patients are
initially prompted to undergo medical treatment. However the vast majority
usually continue to report intense pain or can no longer tolerate long-term
medication, due to undesirable side effects.45 As a result, other
therapeutic alternatives have emerged.
Treatment aims at the removal or destruction of the
nidus, either in the traditional surgical manner by curettage and en-bloc
resection or by other variable percutaneous methods. Current trends have
pointed towards the evolution of less invasive and substantially more time and
cost-effective therapeutic techniques with radiofrequency ablation being the
cornerstone. In 1992, Rosenthal et al37 reported the first clinical
successful application of radiofrequency ablation in the treatment of osteoid
osteomas. Since then numerous retrospective and comparative studies have
established the role of radiofrequency ablation in the treatment armamentary of
small but painful benign bone tumors like osteoid
osteomas.5,10,12,36-53 Nonetheless radiofrequency ablation has been
recently used for the treatment of painful bone metastases as well as for
recurrences of chordomas, rhabdomyomas, and
Radiofrequency ablation is a procedure based on inducing
irreversible thermal damage to tissues by using alternating current in the form
of high-frequency radioimpulses produced by a generator and dissipating their
energy as heat via a needle-electrode, adequately positioned inside the
selected area.1,4 The majority of investigators support that while
treating osteoid osteomas, the optimum level for the heating temperature and
duration of each radiofrequency ablation session is 85°C to 90°C for
approximately 4 to 6 minutes.4,11,70
Larger osteoid osteomas (>1 cm) or osteoblastomas are
advocated to be treated with multiple overlapping radiofrequency ablation
sessions by repositioning the needle-electrode.4,11,70 However,
Peyser et al1 and Martel et al,46 in contrast with the
results of other experimental and clinical studies,70,71 exhibited
excellent success rates with minimal complications by using water-cooled tip
electrodes in larger lesions. Recently, bipolar radiofrequency-technology has
gained interest in the management of osteoid osteoma. The efficacy of monopolar
radiofrequency ablation is most commonly hampered by the incidence of skin
burns at the site of neutral electrodes and the formation of aberrant currents
resulting in irregular shape of necrosis or inducing heat at metallic implants.
These drawbacks can be overcome by using bipolar probes.72 Another
innovative approach with promising results was introduced by Cioni et
al,73 who successfully performed radiofrequency ablation by using
probe needles with expandable electrodes in osteoid osteoma with medium to
large size (9.7±4.4 mm) lesions.
The steps of the radiofrequency ablation procedure per
se have been scrupulously described.4 In the present study, the
authors prefer to highlight special technical considerations. In general, when
peripheral lesions and younger patients are treated percutaneously, general
anesthesia should be preferred to attain patient’s stability and
sufficient control of anxiety.2,11,49 Exceptionally, in spinal
lesions extra care should be taken for the early detection of impending damage
to neural structures so, conscious sedation or local anesthesia should be
The access route should be designed in the CT-suite,
usually preferring the nonaffected, opposite cortex side, hence avoiding
immediate contact with adjacent neurovascular bundles and unwanted positioning
of the probe-electrode close to the skin.45 Thermal skin damages can
also be avoided by using specially designed insulating sheaths or by slightly
withdrawing the penetrating cannula.4,7,45 Although potentially
effective alternatives exist, most investigators prefer the surgical access for
lesions in proximity (<3 cm) with the skin and neurovascular bundles
(≤1.5 cm).11,45 However, lesions of the femoral neck or closely
sited to an open growth plate can be successfully approached by adequately
rotating the affected limb and angulating the access penetrating
Radiofrequency ablation of spinal lesions remains a
challenging but still controversial field. In 1998, Osti and
Sebben38 were the first to successfully use this technique in the
management of spinal osteoid osteomas. According to Dupuy et al,74
radiofrequency ablation can be safely applied in the spine provided that the
lesion’s size is <12 mm and it is surrounded either by cortex or a
thick sclerotic “insulating” rim. In this experimental study no
cytotoxic alterations were recorded in the spinal canal. The so called
“heat sink” effect, due to the presence of the rich epidural venous
plexus and the cerebrospinal fluid circulation, served as the theoretical
rationale for this observation.74 However, for the past decade
several reports have tried to assess clinically radiofrequency ablation’s
effectiveness and safety at this complex anatomic site, coming up with
inconsistent results.12,38,44,51-53 Vanderschueren et
al12 in 2002, reported their experience with a few cases that
resulted in a success rate not >50%, with surgery being the only option in
cases of failure. In view with a substantial risk of harming noble spinal
structures, lesions located closer than 1 cm to neural elements are not good
candidates for radiofrequency ablation and should be referred for surgical
In contrast to open surgery, lack of histological proof
is a major concern regarding radiofrequency ablation and other percutaneous
methods. Although biopsy specimens can be obtained through the initial access
procedure, it is not routinely performed and it is not always feasible to
obtain sufficient specimen of hard osteoid tissue given the small caliber of
the needles used.44 The latter justifies the relative low percentage
of diagnostic results (≤50%) yielded from most percutaneous biopsies of
osteoid osteomas.5,12,21,47 In a wide review of the literature,
osteoid osteoma tissue sampling is rarely performed and usually provides
nondiagnostic information; however paradoxically post-radiofrequency ablation
clinical outcomes are excellent.7 The combination of multiple
imaging modalities and clinical symptoms seem to improve greatly the diagnostic
confidence and assist physicians with the correct patient
selection.5 As suggested by Campanacci et al,14 biopsy
should be reserved only in cases where imaging and clinical findings are not in
accordance, or when the imaging profile is unusual.
Radiofrequency ablation of osteoid osteomas has advanced
in parallel with surgical interventions. A literature search of radiofrequency
ablation articles yielded approximately 789 cases of osteoid osteomas, of all
locations, treated with percutaneous radiofrequency ablation since 1992 (Table
1). Series with a sufficient number of patients (n>20) and mean follow-up
(>22 months) included a total of 535 patients of whom 463 (86.5%) were
successfully treated with initial radiofrequency ablation. In the remaining 72
patients (13.4%), initial radiofrequency ablation failed and a subsequent
radiofrequency ablation session was performed with success in 49 (68%) of these
initially failed cases resulting thus in a total secondary success rate of
95.7% (512/535). The remaining 23 patients (32%) were either treated surgically
(8/23) or left with residual but tolerable pain or eventually were scheduled
for a third radiofrequency ablation session. When biopsies were performed,
histological verification was available in 8.3% to 75% of cases treated with
radiofrequency ablation (Table 1). Nonetheless, the method was not associated
with any major complications, except for 1 case of pyogenic arthritis. The
overall incidence of complications remains satisfactorily low (10
complications/535 cases: 1.8% [Table 1]). In agreement with published data, the
authors have also experienced positive clinical response by performing
radiofrequency ablation to 26 consecutive patients with appendicular osteoid
osteomas, from 2002 until 2007. Reported primary and secondary clinical success
was 88.5% and 92.3%, respectively, in a follow-up period of 6 to 50 months.
Finally, 1 (3.8%) of the 2 untreated patients underwent curettage and the other
patient (3.8%) refused further treatment and had persistent, but not
restrictive, tolerable pain. Two cases of arthritis, 1 of which was complicated
with infection and cutaneous fistula, were encountered in the knee and the hip
In an attempt to identify impending risk factors that
jeopardize the clinical importance of radiofrequency ablation and favor
recurrence, most authors agree that lesion size (≥10 mm) matters. It is well
known that radiofrequency ablation induces overlapping spherical areas of
coagulative necrosis measuring approximately 10 mm4,50; therefore,
it is possible that parts of the tumor outside these spheres are not totally
ablated, especially when its shape is more elongated or oval. Multiple needle
positions or the use of cooled-tip electrodes represent the recommended
alternatives.1,4,46,68,70 Additionally, Rosenthal et al44
and Vanderschueren et al12 support that history of prior treatment
(radiofrequency ablation or surgery) with a pain-free interval followed by
relapse is related to a poor-post second radiofrequency ablation clinical
outcome but this conviction is not uniformly accepted as other investigators
presented with different results.48 There is variety in the duration
of follow-up periods among several studies that should be extended beyond 24
months to meet with orthopedic standards and produce reliable
results.44 However, Cribb et al48 found in a series of 45
patients that nondiaphyseal location is strongly related (P<.01) to
recurrence. A possible explanation for this is that diaphyseal lesions are more
“contained” by the surrounding cortical thickening and thus, it is
easier to be treated effectively with radiofrequency ablation. Apart from size
and shape, recurrences occurring within the first year post treatment are most
commonly attributed to inaccurate needle placement owing either to poor
visualization of the nidus or to complex anatomy with difficulties in
access.12,35 However, for recurrences that present after a prolonged
symptom-free interval (≥12 months), it is speculated that they are
stimulated by the regeneration of a new tumor.35 If the latter
proves to be true along with the difficulty in localizing the lesion, it may
justify the occurrence of post surgical recurrences as well.
Surgical interventions of osteoid osteomas require wide
exposure of the bone surrounding the nidus and use gross features for
localization.14 They include mainly en-bloc resection, wide
excision, and the less invasive method of unroofing with intralesional
excision-curettage of the nidus. With the latter, less aggressive approach, the
sclerotic–reactive bone is gradually removed in thin layers, by using
gouges or high speed rotating burrs. As a result, the reddish, punctiform nidus
is revealed and subsequently curetted out of its bed and sent to pathology. The
walls of the nidus are burred out for 1 to 2 mm in all directions and the
remaining cavity is occasionally filled with the pieces of the removed reactive
Surgical success occurred in 376 of 396 reviewed cases
(94.9%), with a sufficient mean follow-up period of 30 to 156 months (Table 2).
Despite these results, the method bears the criticism of causing extensive
tissue damage, thus resulting in considerable morbidity, delayed recovery, and
further cost for the patient and the institutions. The intraoperative
difficulty of precise lesion localization requires, even with the improved less
invasive curettage techniques, substantial bone removal, resulting in
consecutive structural bone weakness that, not unusually, necessitates internal
fixation, bone grafts and prolonged postoperative immobilization, additional
physical therapy, and restriction of activity.
Osteoid osteomas have a propensity for long tubular,
weight-bearing bones, especially the femur, where open resections may impair
not only the vascular supply of the femoral head but also the integrity of the
related articular and epiphyseal surfaces.10,11 It is noteworthy
that despite its aggressive style, surgical efficacy is not infrequently
hampered by failures as well (20 of 396; 5%; Table 2). Among several published
studies, related complications are not negligible with the rate of minor
complications ranging from 7% to 45.5% combined, in most studies, with
fractures and other complications (Table 2). The Rosenthal et al75
comparative study has also shown that radiofrequency ablation is essentially
equivalent to surgery (primary success radiofrequency ablation: 88% versus 91%
and secondary success radiofrequency: 100% versus 90%) and is preferred for the
treatment of osteoid osteomas in the extremities due to its less invasive
In agreement with the recommendation of most authors
surgery should be reserved for either spinal or appendicular lesions in
proximity with neurovascular elements, for cases where the histology is unclear
and also after repeated failures of percutaneous ablation or
resection.5,11,42,44 Additionally, orthopedic surgeons favor the use
of the less invasive curettage for subperiosteal lesions that are easily
accessible and percutaneous methods do not offer any significant
Computed tomography-guided percutaneous resection
requires large skin incisions extending deep into the soft tissues and uses
various trephines and drilling systems with relative large caliber, ranging
from a 14 G cutting needle to a 9-mm drill bit, so as to achieve complete
eradication of the nidus.11 As a result, the term “minimally
invasive” should be used with caution and skepticism when comparing this
technique with radiofrequency ablation and the other percutaneous ablative
methods. Curative rates reach up to 89.5%, 129 successfully treated cases of
144 reviewed cases with a mean follow-up period from 9.8 to 44 months (Table 3)
for initial percutaneous resection. The method can be performed either on
inpatient or on outpatient basis but procedural duration is longer than other
The drilling process usually demands more aggressive
manipulations and can lead to fractures with considerably longer restriction of
activity and weight bearing for up to 3 months7 compared with a
maximum 6 weeks of limitation of strenuous sports, in cases of radiofrequency
ablation.11 Owing to the heat produced by the high rotation speed of
the drilling instruments, especially when powered drills are used without
cooling, more extensive tissue damage is caused in the form of skin burns, bone
weakening, osteonecrosis, and muscle hematomas.5,42 Further
complications include irritation of adjacent nerves and osteomyelitis, and
although the method provides larger tissue specimens for definite histological
diagnosis,5,42 reported overall complication rates may reach up to
24% (Table 3). As a result, CT-guided percutaneous resection is not uniformly
accepted as a minimally invasive method for the management of osteoid osteomas
and further technical optimization is necessitated.
Taking advantage of the augmentation of cellular
desiccation induced by ethanol, several investigators have combined its use
with percutaneous resection with promising preliminary results.27,28
These outcomes refer to small case studies with short follow-up and further
workup is needed, taking into account the nonspecific effects of ethanol
instillation on the surrounding soft tissues and the fact that drill ablation
per se can successfully destroy the nidus.7,11 Ethanol injection has
also been used post-radiofrequency ablation,2 but it is similarly
questionable whether the addition of ethanol increases the effectiveness when
compared with the use of radiofrequency alone. Likewise, because limited data
are available future randomized comparative studies are needed.
Laser technology was first used in the treatment of
tumors by Bown in the 1980s.11 Gangi et al31,32
introduced laser energy in the management of osteoid osteomas in the late 1990s
and since then it has been applied to approximately 153 patients (Table 4).
Laser energy can be transmitted through optic fibers (400 µm) into
selected tissues and cause direct cellular thermal injury and producing thus
controlled areas of coagulative necrosis. Like radiofrequency ablation, the
extent of necrosis is limited by the cooling effect of local blood
Laser interstitial thermal therapy compared to
radiofrequency ablation ensures, in proportion to the energy delivered, better
predictability and control of the size of produced necrosis.11,35
Laser technology has been used successfully in the spine as well. Gangi et
al,31 after treating 3 cases of spinal osteoid osteomas with laser
photocoagulation, initially supported its use with the condition that the laser
needle should be positioned centrally into the nidus, at least 8 mm away from
neural elements. Recently, the same author successfully treated, with laser
ablation, 5 cases of osteoid osteomas that were located closer than 8 mm to
adjacent nerve roots by slowly infusing normal saline into the epidural or
periradicular space so as to avoid thermal injury.35 By inference,
its use has been proposed for all osteoid osteomas, even those located in the
spine where accuracy is needed.35 It can be also performed on an
outpatient basis, uses a less invasive approach, favors rapid recovery, does
not interact with pacemakers, and can safely be repeated, like radiofrequency,
in cases of initial failure but with a higher, yet secondary success rate of
100% in all reported series (Table 4).11,35 Primary success rate is
also slightly superior and it is estimated at 92.8% with an overall of 142
initial successes of 153 reviewed cases with a mean follow-up period ≤58.5
months (Table 4). Although the results are promising, this technique is still
evolving, has a higher cost, is not oblivious to potential failure (7.2%; 11
failures of 153 reviewed cases; Table 4), requires specialized personnel,
cannot provide reliable histological results,11 and presents with
higher, in total, than radiofrequency ablation minor complication rates (Table
The results of this review article suggest that
radiofrequency ablation should be considered as the preferred percutaneous
technique for the treatment of deeply cited or inaccessible, preferably
nonspinal, osteoid osteomas with excellent initial clinical response and
acceptable failure and complication rates. Owing to its minimally invasive
nature, it can be safely and effectively repeated for the management of
persistent or recurrent lesions, without jeopardizing prognosis. Opinion exists
that the efficacy of the method will be further increased with the introduction
of new technical advances such as bipolar technology, cooled-tip, and
expandable probes. Moreover, it does not necessitate prolonged hospital stay
and favors rapid recovery, reducing thus considerably not only the economical
but also the social costs due to restriction or potential impairment of
However, clinical experience with surgical interventions
is not negligible and, according to the established consensus their use should
be reserved for readily accessible subperiosteal lesions and lesions in
proximity with neurovascular structures, when the histology is unclear and
where percutaneous methods have repeatedly failed.
However, serious concerns should be raised when
CT-guided resection is considered as a safe alternative owing to the relatively
high associated morbidity rates presented in some series.
Laser interstitial thermal therapy as an exciting and
upcoming alternative, creates new horizons in the treatment of all osteoid
osteomas regardless of location, especially in spinal lesions where accuracy
and safety are most needed; by exhibiting more than promising primary and
secondary success rates.
- Peyser A, Appplbaum Y, Khoury A, Lieberrgall M, Atesok K. Osteoid
osteoma: CT-guided radiofrequency ablation using a water-cooled probe. Ann
Surg Oncol. 2007; 14(2):591-596.
- Yip PS, Lam YL, Chan MK, Shu JS, Lai KC, So YC. Computed
tomography-guided percutaneous radiofrequency ablation of osteoid osteoma:
local experience. Hong Kong Med J. 2006; 12(4):305-309.
- Akhlaghpoor S, Tomasian A, Arjmand Shabestari A, Ebrahimi M,
Alinaghizadeh MR. Percutaneous osteoid osteoma treatment with combination of
radiofrequency and alcohol ablation. Clin Radiol. 2007; 62(3):268-273.
- Pinto CH, Taminiau AH, Vanderschueren GM, Hogendoorn PC, Bloem JL,
Obermann WR. Technical considerations in CT-guided radiofrequency thermal
ablation of osteoid osteoma: tricks of the trade. AJR Am J Roentgenol.
- Lindner NJ, Ozaki T, Roedl R, Gosheger G, Winkelmann W, Wörtler
K. Percutaneous radiofrequency ablation in osteoid osteoma. J Bone Joint
Surg Br. 2001; 83(3):391-396.
- Jaffe HL. ‘Osteoid Osteoma,’ a benign osteoblastic tumor
composed of osteoid and atypical bone. Arch Surg. 1935; 31:709-712.
- Ghanem I. The management of osteoid osteoma: updates and
controversies. Curr Opin Pediatr. 2006; 18(1):36-41.
- Allen SD, Saifuddin A. Imaging of intra-articular osteoid osteoma.
Clin Radiol. 2003; 58(11):845-852.
- Schajowicz F, Lemos C. Osteoid osteoma and osteoblastoma. Closely
related entities of osteoblastic derivation. Acta Orthop Scand. 1970;
- Venbrux AC, Montague BJ, Murphy KP, et al. Image-guided percutaneous
radiofrequency ablation for osteoid osteomas. J Vasc Interv Radiol.
- Cantwell CP, Obyrne J, Eustace S. Current trends in treatment of
osteoid osteoma with an emphasis on radiofrequency ablation. Eur Radiol.
- Vanderschueren GM, Taminiau AH, Obermann WR, Bloem JL. Osteoid
osteoma: clinical results with thermocoagulation. Radiology. 2002;
- Hadjipavlou AG, Lander PH, Marchesi D, Katonis PG, Gaitanis IN.
Minimally invasive surgery for ablation of osteoid osteoma of the spine.
Spine. 2003; 28(22):E472-E477.
- Campanacci M, Ruggieri P, Gasbarrini A, Ferraro A, Campanacci L.
Osteoid osteoma. Direct visual identification and intralesional excision of the
nidus with minimal removal of bone. J Bone Joint Surg Br. 1999;
- Ward WG, Eckardt JJ, Shayestehfar S, Miarra J, Grogan T, Oppenhiem W.
Osteoid osteoma diagnosis and management with low morbidity. Clin Orthop
Relat Res. 1993; (291):229-235.
- Yildiz Y, Bayrakci K, Altay M, Saglik Y. Osteoid osteoma: the results
of surgical treatment. Int Orthop. 2001; 25(2):119-122.
- Sluga M, Windhager R, Pfeiffer M, Dominkus M, Kotz R. Peripheral
osteoid osteoma. Is there still a place for traditional surgery? J Bone
Joint Surg Br. 2002; 84(2):249-251.
- Pfeiffer M, Sluga M, Windhager R, Dominkus M, Kotz R. Surgical
treatment of osteoid osteoma of the extremities [in German]. Z Orthop Ihre
Grenzgeb. 2003; 141(3):345-348.
- Voto SJ, Cook AJ, Weiner DS, Ewing JW, Arrington LE. Treatment of
osteoid osteoma by computed tomography-guided excision in the pediatric
patient. J Pediatr Orthop. 1990; 10(4):510-513.
- Assoun J, Railhac JJ, Bonnevialle P, et al. Osteoid osteoma:
percutaneous resection with CT guidance. Radiology. 1993;
- Kohler R, Rubini J, Postec F, Canterino I, Archimbaud F. Treatment of
osteoid osteoma by CT-controlled percutaneous drill resection. Apropos of 27
cases. Rev Chir Orthop Reparatrice Appar Mot. 1995; 81(4):317-325.
- Roger B, Bellin MF, Wioland M, Grenier P. Osteoid osteoma: CT-guided
percutaneous excision confirmed with immediate follow-up scintigraphy in 16
outpatients. Radiology. 1996; 201(1):239-242.
- Parlier-Cuau C, Champsaur P, Nizard R, Hamze B, Laredo JD.
Percutaneous removal of osteoid osteoma. Radiol Clin North Am. 1998;
- Parlier-Cuau C, Nizard R, Champsaur P, Hamze B, Laredo JD.
Percutaneous resection of osteoid osteoma. Semin Musculoskelet Radiol.
- Sans N, Galy-Fourcade D, Assoun J, et al. Osteoid osteoma: CT-guided
percutaneous resection and follow-up in 38 patients. Radiology. 1999;
- Fenichel I, Garniack A, Morag B, Palti R, Salai M. Percutaneous
CT-guided curettage of osteoid osteoma with histological confirmation: a
retrospective study and review of the literature. Int Orthop. 2006;
- Duda SH, Schnatterbeck P, Härer T, Giehl J, Böhm P,
Claussen CD. Treatment of osteoid osteoma with CT-guided drilling and ethanol
instillation. Dtsch Med Wochenschr. 1997; 122(16):507-510.
- Adam G, Neuerburg J, Vorwerk D, Forst J, Gunther RW. Percutaneous
treatment of osteoid osteomas: combination of drill biopsy and subsequent
ethanol injection. Semin Musculosket Radiol. 1997; 1(2):281-284.
- Khapchik V, O’Donnell RJ, Glick JM. Arthroscopically assisted
excision of osteoid osteoma involving the hip. Arthroscopy. 2001;
- Skjedal S, Lilleås F, Follerås G, et al. Real-time
MRI-guided excision and cryo-treatment of osteoid osteoma in os ischii: a case
report. Acta Orthop Scand. 2000; 71(6):637-638.
- Gangi A, Dietemann JL, Guth S, et al. Percutaneous laser
photocoagulation of spinal osteoid osteoma under CT guidance. AJNRAm J
Neuroradiol. 1998; 19(10):1955-1958.
- Gangi A, Dietemann JL, Gasser B, et al. Interventional radiology with
laser in bone and joint. Radiol Clin North Am. 1998; 36(3):547-557.
- Witt JD, Hall-Craggs A, Ripley P, Cobb JP, Bown SG. Interstitial
laser photocoagulation for the treatment of osteoid osteoma. J Bone Joint
Surg Br. 2000; 82(8):1125-1128.
- Sequeiros RB, Hyvönen P, Sequeiros AB, et al. MR imaging-guided
laser ablation of osteoid osteomas with use of optical instrument guidance at
0.23 T. Eur Radiol. 2003; 13(10):2309-2314.
- Gangi A, Alizadeh H, Wong L, Buy X, Dietemann JL, Roy C. Osteoid
osteoma: Percutaneous laser ablation and follow-up in 114 patients.
Radiology. 2007; 242(1):293-301.
- Gebauer B, Tunn PU, Gaffke G, Melcher I, Felix R, Stroszczynski C.
Osteoid osteoma: experience with laser- and radiofrequency-induced ablation.
Cardiovasc Intervent Radiol. 2006; 29(2):210-215.
- Rosenthal DI, Alexander A, Rosenberg AE, Sprongfield D. Ablation of
osteoid osteomas with percutaneously placed electrode: a new procedure.
Radiology. 1992; 183(1):29-33.
- Osti OL, Sebben R. High-frequency radio-wave ablation of osteoid
osteoma in the lumbar spine. Eur Spine J. 1998; 7(5):422-425.
- de Berg JC, Pattynama PM, Obermann WR, Bode PJ, Vielvoye GJ, Taminiau
AH. Percutaneous computed tomography-guided thermocoagulation for osteoid
osteomas. Lancet. 1995; 346(8971):350-351.
- Rosenthal DI. Percutaneous radiofrequency treatment of osteoid
osteomas. Semin Musculoskelet Radiol. 1997; 1(2):265-272.
- Barei DP, Moreau G, Scarborough MT, Neel MD. Percutaneous
radiofrequency ablation of osteoid osteoma. Clin Orthop Relat Res. 2000;
- Woertler K, Vestring T, Boettner F, Winkelmann W, Heindel W, Lindner
N. Osteoid osteoma: CT-guided percutaneous radiofrequency ablation and
follow-up in 47 patients. J Vasc Intervent Radiol. 2001; 12(6):717-722.
- Ghanem I, Collet LM, Kharrat K, et al. Percutaneous radiofrequency
coagulation of osteoid osteoma in children and adolescents. J Pediatr Orthop
B. 2003; 12(4):244-252.
- Rosenthal DI, Hornicek FJ, Torriani M, Gebhardt M, Mankin HJ. Osteoid
osteoma: Percutaneous treatment with radiofrequency energy. Radiology.
- Cioni R, Armillotta N, Bargellini I, et al. CT-guided radiofrequency
ablation of osteoid osteoma: long-term results. Eur Radiol. 2004;
- Martel J, Bueno A, Ortiz E. Percutaneous radiofrequency treatment of
osteoid osteoma using cool-tip electrodes. Eur J Radiol. 2005;
- Rimondi E, Bianchi G, Malaguti MC, et al. Radiofrequency
thermoablation of primary non-spinal osteoid osteoma: optimization of the
procedure. Eur Radiol. 2005; 15(7):1393-1399.
- Cribb GL, Goude WH, Cool P, Tins B, Cassar-Pullicino VN, Mangham DC.
Percutaneous radiofrequency thermocoagulation of osteoid osteomas: factors
affecting therapeutic outcome. Skeletal Radiol. 2005; 34(11):702-706.
- Shinozaki T, Sato J, Watanabe H, et al. Osteoid osteoma treated with
computed tomography-guided percutaneous radiofrequency ablation: a case series.
J Orthop Surg. 2005; 13(3):317-322.
- Kjar R, Powell G, Schilcht S, Smith P, Slavin J, Choong P.
Percutaneous radiofrequency ablation for osteoid osteoma: experience with a new
treatment. Med J Aust. 2006; 184(11):563-565.
- Samaha E, Ghanem I, Moussa R, Kharrat K, Okais N, Dagher F.
Percutaneous radiofrequency coagulation of osteoid osteoma of the “Neural
Spinal Ring.” Eur Spine J. 2005; 14(7):702-705.
- Cove JA, Taminiau AH, Obermann WR, Vanderschueren GM. Osteoid osteoma
of the spine treated with percutaneous computed tomography-guided
thermocoagulation. Spine. 2000; 25(10):1283-1286.
- Raskas DS, Graziano GP, Hensinger RN. Osteoid osteoma and
osteoblastoma of the spine. J Spinal Disord. 1992; 5(2):204-211.
- Pieterse AS, Vernon-Roberts B, Paterson DC, Cornish BL, Lewis PR.
Osteoid osteoma transforming to aggressive (low grade malignant )
osteoblastoma: a case report and literature review. Histopathology.
- Golding JS. The natural history of osteoid osteoma. With a report of
twenty cases. J Bone Joint Surg Br. 1954; 36(2):218-229.
- Vickers CW, Pugh DC, Ivins JC. Osteoid osteoma; a fifteen year
follow-up of an untreated patient. J Bone Joint Surg Am. 1959;
- Jaffe H. “Osteoid osteoma”: a benign osteoblastic tumor
composed of atypical bone. Arch Surg. 1935; 31:709-728.
- Klein MJ, Parisien MV, Schneider-Stock R. Osteoid osteoma. In:
Fletcher CDM, Unni KK, Mertens F, eds. World Health Organization
Classification of Tumours: Pathology and Genetics: Tumours of Soft Tissue and
Bone. Lyon, France: IARCPress. 2002, 260-261.
- Hasegawa T, Hirose T, Sakamoto R, Seki K, Ikata T, Hizawa K.
Mechanism of pain in osteoid osteomas: an immunohistochemical study.
Histopathology. 1993; 22(5):487-491.
- Greco F, Tamburrelli F, Laudati A, La Cara A, Di Trapani G. Nerve
fibres in osteoid osteoma. Ital J Orthop Traumatol. 1988; 14(1):91-94.
- Schulman L, Dorfman HD. Nerve fibres in osteoid osteoma. J Bone
Joint Surg Am. 1970; 52(7):1351-1356.
- Thomas A. Vascular tumors of bone. Surgery, Gynecology and
Obstetrics. 1942; 74:777.
- Davies M, Cassar-Pullicino VN, Davies AM, McCall IW, Tyrrell PN. The
diagnostic accuracy of MR imaging in osteoid osteoma. Skelet Radiol.
- Spouge AR, Thain LM. Osteoid osteoma: MR imaging of two untreated
lesions. Clin Imaging. 1999; 23(4):254-258.
- Spouge AR, Thain LM. Osteoid osteoma: MR imaging revisited. Clin
Imaging. 2000; 24(1):19-27.
- Assoun J, Richardi G, Railhac J, et al. Osteoid osteoma: MR imaging
versus CT. Radiology. 1994; 191(1):217-223.
- Liu PT, Chivers FS, Roberts CC, Schultz CJ, Beauchamp CP. Imaging of
osteoid osteoma with dynamic gadolinium-enhanced MR imaging. Radiology.
- Tins B, Cassar-Pullicino V, McCall I, Cool P, Williams D, Mangham D.
Radiofrequency ablation of chondroblastoma using a multi-tined expandable
electrode system: initial results. Eur Radiol. 2006; 16(4):804-810.
- Petsas T, Megas P, Papathanassiou Z. Radiofrequency ablation of two
femoral head chondroblastomas. Eur J Radiol. 2007; 63(1):63-67.
- Vanderschueren GM, Taminiau AH, Obermann WR, van den Berg-Huysmans
AA, Bloem JL. Osteoid osteoma: Factors for increased of unsuccessful thermal
coagulation. Radiology. 2004; 233(3):757-762.
- Matsumoto N, Kishi R, Kasugai H, et al. Experimental study on the
effectiveness and safety of radiofrequency catheter ablation with cooled
ablation system. Circ J. 2003; 67(2):154-158.
- Mahnken AH, Tacke JA, Wildberger JE, Günther RW. Radiofrequency
ablation of osteoid osteoma: initial results with a bipolar ablation device.
J Vasc Interv Radiol. 2006; 17(9):1465-1470.
- Cioni R, Crocetti L, Lencioni R, Zampa V, Bozzi E, Montagnani S,
Della Pina C, Bartolozzi C. Percutaneous CT-guided RF ablation of osteoid
osteoma with multitined expandable electrode. Paper presented at: The European
Congress of Radiology; March 9-13, 2007; Vienna, Austria.
- Dupuy DE, Hong R, Oliver B, Goldberg SN. Radiofrequency ablation of
spinal tumors: temperature distribution in the spinal canal. AJR Am J
Roentgenol. 2000; 175(5):1263-1266.
- Rosenthal DI, Hornicek FJ, Wolfe MW, Jennings LC, Gebhardt MC, Mankin
HJ. Percutaneous radiofrequency coagulation of osteoid osteoma compared with
operative treatment. J Bone Joint Surg Am. 1998; 80(6):815-821.
Drs Papathanassiou, Petsas, Nilas, and Siablis are from
the Department of Radiology and Dr Megas is from the Orthopedic Clinic,
University Hospital, Patras, Greece; and Dr Papachristou is from the Department
of Pathology, University of Pittsburgh Medical Center, Pittsburgh,
Drs Papathanassiou, Megas, Petsas, Papachristou, Nilas,
and Siablis have no relevant financial relationships to disclose. Dr Morgan,
CME Editor, has disclosed the following relevant financial relationships:
Stryker, speakers bureau; Smith & Nephew, speakers bureau, research grant
recipient; AO International, speakers bureau, research grant recipient;
Synthes, institutional support. Dr D’Ambrosia, Editor-in-Chief, has no
relevant financial relationships to disclose. The staff of
Orthopedics have no relevant financial relationships to disclose.
The material presented at or in any Vindico Medical
Education continuing education activity does not necessarily reflect the views
and opinions of Vindico Medical Education or Orthopedics. Neither
Vindico Medical Education or Orthopedics, nor the faculty endorse
or recommend any techniques, commercial products, or manufacturers. The
faculty/authors may discuss the use of materials and/or products that have not
yet been approved by the US Food and Drug Administration. All readers and
continuing education participants should verify all information before treating
patients or utilizing any product.
Correspondence should be addressed to: Zafiria G.
Papathanassiou, MD, Department of Radiology, University Hospital, Patras, Rio