Radiofrequency ablation of osteoid osteoma in atypical locations: a case series

Short- and Long-Term Outcomes after Radiofrequency Ablation of Osteoid Osteomas

The aim of this study was to evaluate treatment of osteoid osteomas using bipolar radiofrequency ablation (RFA) and patients' quality of life before and after therapy. We retrospectively evaluated patients who underwent bipolar RFA of osteoid osteomas between 2001 and 2016. We assessed patients' symptoms before and after treatment (four weeks after treatment and long-term) using a questionnaire including severity and quality of pain on a 10-point scale (1 = no pain, 10 = severe pain), motion restrictions, pain-related sleep disorders, and necessary pain medication. In addition, we evaluated technical success, complications, hospitalization length, and patients' satisfaction with treatment. This study included 62 patients (43 [69.4%] males, 26.2 ± 13.2 years). Average nidus size was 5.7 ± 2.6 mm. The rate of technical success was 100%. All RFAs were performed without any complications. One patient showed a recurrence, resulting in a recurrence rate of 1.6%, which was successfully treated by another session of RFA. Average hospitalization length was 1.5 ± 0.5 days. A total of 36 patients (58.1%) participated in the questionnaire, reporting an average pain severity of 8.2 ± 1.6 before RFA compared to 3.4 ± 3.0 four weeks after and an average of 2.1 ± 2.3, 6.6 years after therapy, (both p < 0.001). After therapy, 31 (86.1%) patients had no pain. The majority of patients (n = 34, 94.4%) had reduced or absent motion restriction after therapy (p < 0.001). Patient satisfaction rate was 91.7%. In conclusion, bipolar RFA is a safe and effective treatment modality for osteoid osteomas and improves quality of life by reducing pain severity and motion restrictions.

Comparison of arthroscopy versus percutaneous radiofrequency thermal ablation for the management of intra- and juxta-articular elbow osteoid osteoma: case series and a literature review

BACKGROUND

Today, intra-articular and juxta-articular osteoid osteomas are treated with arthroscopy and radiofrequency thermal ablation. However, for the case of an elbow joint, arguments are made for the use of a minimally invasive technique to be the optimal choice. This study aims to analyse our experiences of arthroscopically treated elbow osteoid osteomas and to compare it with the published results of both techniques.

METHODS

The retrospective study analyses the patients who underwent elbow arthroscopy ablation of an elbow osteoid osteoma at a single institution from January 2014 until March 2020. Clinical and diagnostic features, success and treatment failure rates, complications and tumour recurrence rates were all compared to 13 studies of intra-articular elbow osteoid osteoma arthroscopic ablation and 15 studies involving radiofrequency thermal ablation of intra-articular osteoid osteoma within different joints.

RESULTS

Four males and two females, with a mean age of 19.3 years, were encompassed. All the patients had immediate postoperative pain relief and improved range of motion. No tumour recurrences were observed during a median of 21.7 months. The literature review yielded 86.4% success rate, 68.2% successful biopsies, one minor complication and no recurrences following the arthroscopic ablation of an elbow osteoid osteoma; while radiofrequency thermal ablation of an intra-articular elbow osteoid osteoma yielded 96.3% success rate, 33.3% successful biopsies, no complications and 3.7% recurrence rate.

CONCLUSIONS

Our results are consistent with the published literature proving that arthroscopic ablation is an efficient method with low treatment failure rates and no recurrences in treating intra- and juxta-articular elbow osteoid osteomas. Advantages of arthroscopic ablation stem from the ability to visualise and safely deal with the lesion and the joint's reactive changes resulting in high biopsy rates, no recurrences and better postoperative elbow's range of motion. Still, the technique selection should be personalised considering the medical expertise of every institution.

Hip arthroscopy has good clinical outcomes in the treatment of osteoid osteoma of the acetabulum

BACKGROUND

Osteoid osteoma (OO) of the acetabulum is a relatively rare disease. However, the the clinical outcomes of hip arthroscopy for treatment of OO of the acetabulum are still uncertain.

METHODS

We evaluated consecutive patients who were diagnosed with OO of the acetabulum and who underwent hip arthroscopy at our hospital between January 2013 and March 2020. All patients underwent a preoperative physical examination. Preoperative supine anteroposterior hip radiography, cross-table lateral radiographs, computed tomography (CT), and magnetic resonance imaging were performed in all patients. The alpha angle and lateral center-edge angle were measured before surgery. Supine anteroposterior hip radiography and CT were performed in all patients postoperatively. Preoperative patient-reported outcomes (PROs), including Visual Analog Scale (VAS), the International Hip Outcome Tool-12 (iHOT-12) and modified Harris Hip Score (mHHS), and PROs at final follow-up were evaluated.

RESULTS

A total of 6 patients (mean age, 18.7 years; age range, 6-31 years; 5 males and 1 females) were included in this study. The average follow-up period after surgery was 28.3 months (range, 6-90 months). Before surgery, the mean mHHS was 45.2 ± 10.5 (range, 33-56), the mean iHOT-12 was 33.3 ± 14.5 (range, 13-49), and mean VAS was 8.2 ± 1.0 (range, 7-9). At one month after surgery, mean mHHS was 78.7 ± 1.9 (range, 77-81), iHOT-12 was 71.0 ± 4.5 (range, 68-80), and mean VAS was 0. At the final post-operative follow-up, mean mHHS was 89.2 ± 2.1 (range, 86-91), iHOT-12 was 93.5 ± 5.0 (range, 88-98), and mean VAS was 0. All results, except VAS between one month after surgery and at final follow-up, demonstrated statistically significant improvement (P < 0.05). One patient underwent revision surgery.

CONCLUSIONS

Hip arthroscopy has good clinical outcomes in the treatment of OO of the acetabulum. Further study on the mechanism of secondary femoroacetabular impingement (FAI) caused by OO of the acetabulum is needed. More cases of arthroscopic excision and longer follow-up are also needed to better prove the clinical outcomes of hip arthroscopy for OO of the acetabulum.

Osteoid osteoma: which is the best mininvasive treatment option?

Osteoid osteoma is the third most common benign bone tumor, with well-known clinical presentation and radiological features. Although surgical excision has been the only therapeutic option for a long time, to date it has been replaced by minimally invasive techniques, which proved satisfactory success rates and low complication occurrence. Therefore, the purpose of this literature review was to describe the main updates of these recent procedures in the field of interventional radiology, with particular attention paid to the results of the leading studies relating to the efficacy, complications, and recurrence rate. Nevertheless, this study aimed to analyze the peculiarities of each reported technique, with specific focus on the possible improvements and pitfalls. Results proved that all mininvasive procedures boast a high success rate with slight number of complications and a low recurrence rate. Radiofrequency ablation is still considered the gold standard procedure for percutaneous treatment of osteoid osteoma, and it has the possibility to combine treatment with a biopsy. Interstitial laser ablation's advantages are the simplicity of use and a lower cost of the electrodes, while cryoablation allows real-time visualization of the ablated zone, increasing the treatment safety. Magnetic resonance-guided focused ultrasound surgery is the most innovative non-invasive procedure, with the unquestionable advantage to be radiation free.

Effectiveness and reliability of traditional open surgery in atypical localizations of osteoid osteoma

Objectives

This study aims to evaluate traditional open surgery results of osteoid osteomas (OOs) in atypical localizations and explore whether open surgery can be a safe alternative in localizations where radiofrequency ablation (RFA) may not be suitable.

Patients and methods

A total of 26 patients (20 males, 6 females; mean age 23.3±14.2 years; range, 4 to 65 years) having OO in atypical localizations between January 2008 and January 2017 were retrospectively evaluated. All patients underwent traditional open surgery under anesthesia. All patients were followed-up, and their clinical success and complications were evaluated. The pain intensity was assessed using the visual analog scale (VAS).

Results

The postoperative first year VAS score was 0.2±0.5 (range, 0-2) (p<0.005). None of the patients showed any complications. No recurrences were reported at the end of the first year. All patients were relieved from pain due to OO in atypical localizations.

Conclusion

Although RFA has been accepted as the preferred treatment for OO, traditional open surgery may still be used for OO in atypical localizations yielding perfect clinical results with fewer complications. It is a safe alternative for localizations such as carpal bones, distal ulna, hand and foot where RFA complications can be seen more frequently. In these localizations, traditional open surgery can be recommended as the first treatment choice.

Computed Tomography-Guided Radiofrequency Ablation of Osteoid Osteoma in Atypical Sites: Efficacy and Safety in a Large Case Series

RATIONALE AND OBJECTIVES

Although computed tomography (CT) guided radiofrequency ablation (RFA) is accepted as the gold standard treatment for osteoid osteoma (OO) in extremities, most researchers have omitted OO in critical sites. We aimed to evaluate the efficacy and safety of CT-guided RFA in the management of OO in atypical sites.

MATERIALS AND METHODS

A prospective interventional study conducted on 34 patients (12 women and 22 men; mean age, 22.3 ± 3.5 years; range, 12-48 years) with OO in atypical sites. All patients were treated with CT-guided RFA. All procedures were performed under general anesthesia using a single straight, rigid RF electrode for 6 minutes at 90°C. All patients were followed up; technical and clinical successes of treatment were evaluated. The severity of pain was assessed on a visual analogue scale (VAS).

RESULTS

CT-guided RFA was performed in all patients with 100% technical success and 100% primary clinical success. All patients had complete pain relief and returned to their quality of life without further analgesics within 1 month after the procedure. All procedures were successfully completed without any major complications. The mean preprocedure VAS score dropped to zero by the end of the first week with a highly statistically significant difference (p < 0.001).

CONCLUSION

CT-guided RFA is a safe and effective procedure in the management of OO in atypical sites with 100% primary success rate, 0% long-term recurrence rate, and very low complication rate.

Percutaneous thermal ablation for treatment of osteoid osteoma: a systematic review and analysis

OBJECTIVE

Although radiofrequency ablation is well validated for treatment of osteoid osteoma, newer technologies, namely cryoablation, have been less thoroughly studied. The purpose is to perform a systematic review and pooled analysis of percutaneous ablation technologies for treatment of osteoid osteoma with subset analysis of intra-articular and spinal tumors.

MATERIAL AND METHODS

A total of 36 of 79 identified manuscripts met inclusion criteria, comprising 1863 ablations in 1798 patients. Inclusion criteria were (1) retrospective or prospective analysis of thermal ablation of osteoid osteomas in any location, (2) at least 6 months of clinical follow-up, (3) 10 or more patients, (4) patients not included in a second study included in this review, and (5) English language or English translation available. Success rate was defined as all ablations minus technical failures, clinical failures, and recurrences. Subset analysis of intra-articular and spinal tumors was performed.

RESULTS

Overall success rate was 91.9% (95% CI 91-93%). Technical failure, clinical failure, and recurrence rates were 0.3%, 2.1%, and 5.6% respectively. Complications were seen in 2.5% (95% CI 1.9-3.3%) patients. There was no significant difference when comparing radiofrequency ablation and cryoablation (p = 0.92). Success rates for intra-articular (radiofrequency ablation) and spinal tumors (radiofrequency and cryoablation) were 97% and 91.6% respectively.

CONCLUSION

Percutaneous ablation of osteoid osteomas was highly successful with low complication rates. Efficacy of radiofrequency ablation and cryoablation is similar, which is consequential because cryoablation is associated with decreased pain, predictable nerve regeneration, and theoretical immunotherapy benefits. Treatment of more challenging intra-articular and spinal lesions demonstrated similarly high success and low complication rates.

CT-guided radiofrequency ablation for osteoid osteomas: a systematic review

OBJECTIVES

CT-guided radiofrequency ablation (CT-RFA) is considered to be the gold standard for treatment of osteoid osteoma (OO) yet treatment failures (TFs) continue to be reported. This systematic review was conducted to evaluate factors associated with TF, such as ablation time, lesion location, and patient age as well as evaluating how TF has trended over time.

METHODS

Original studies reporting on patients undergoing CT-RFA of OO published between 2002 and 2019 were identified. TF was defined as patients with (1) recurrent or persistent pain +/- (2) imaging evidence of persistent OO. TFs were subdivided into those occurring after the index procedure (primary TF) or those occurring after repeat RFA (secondary TF). Subgroup analysis was performed for TF based on the study date (2002-2010 or 2010-2019), time duration of ablation at 90 °C (6 min or > 6 min), patient age, and tumor location (spinal vs. appendicular).

RESULTS

Sixty-nine studies were included for a total of 3023 patients. The global primary TF rate was 8.3% whereas the secondary TF rate was 3.1%. The TF rate reported in studies published after 2011(7%) was about half that during the earlier time period 2002-2010 (14%). There was no statistical difference in TF corrected for age, OO location, or duration of ablation (respectively p = 0.39, 0.13, and 0.23). The global complication rate was 3%, the most frequent being skin burns (n = 24; 0.7%).

CONCLUSIONS

A decrease in TF observed between 2011-2019 compared to 2002-2010 may reflect improvements in operator technique or advancements in equipment. Duration of ablation, patient age, or location of OO failed to significantly correlate with TF.

KEY POINTS

• CT-guided radiofrequency ablation of osteoid osteomas is a safe technique with a low rate of treatment failure (8.3% failure rate after the primary radiofrequency reducing to 3.1% following a secondary treatment). • The treatment failure rate has decreased over time, possibly due to an improved understanding of the disease process, better technique, and advances in equipment. • Duration of ablation, patient age, or lesion location did not significantly correlate with treatment failure.

Arthroscopic management of intra- and juxta-articular osteoid osteoma of the upper extremity: a systematic review of the literature

BACKGROUND

Intra- and juxta-articular osteoid osteoma (OO) is rare and can result in irreversible joint damage. Recently, arthroscopic surgery is being used more and more to avoid complications associated with other treatment modalities.

METHODS

On October 13, 2019, we conducted a systematic review of the literature available in PubMed and EMBASE regarding the arthroscopic management of OO involving the joints of the upper extremity. Predetermined inclusion criteria were used to include any relevant article published on and before that date for further analysis. Treatment success rate and tumor recurrence rate were considered the primary outcomes in our analysis.

RESULTS

Out of 113 studies, 19 met our inclusion criteria. Of the 32 reported cases in these 19 articles, ten involved the shoulder joint, 19 involved the elbow joint and three involved the wrist joint. Overall treatment success rate was 93.8%. Tumor recurrence rate was 0.0%. No postoperative complications (0.0%) were reported among cases involving the shoulder joint. Two out of 24 (8.3%) patients with elbow OO failed arthroscopic treatment due to incomplete excision, and two (4%) experienced minor complications. Among the three cases of wrist OO, two (66.7%) patients had residual postoperative pain and decreased hand grip strength.

CONCLUSION

Arthroscopic management of OO of the upper extremity joints is highly successful and results in no tumor recurrence; however, there is a risk of incomplete resection in areas more difficult to access by arthroscopy.

A case report of an unrecognized osteoid osteoma of the proximal femur

We present the case of a 59-year-old male patient with unrecognized osteoid osteoma in radiography as well as in magnetic resonance imaging. Computed tomography revealed osteoid osteoma that was successfully treated with percutaneous computed tomography guided radiofrequency ablation. The osseous pathology was underestimated on magnetic resonance imaging in the presented case and bone marrow edema led to incorrect diagnosis. The particular case emphasizes the value of computed tomography scans diagnosing an osteoid osteoma.

Computed tomography guided radio-frequency ablation of osteoid osteomas in atypical locations

Purpose

Percutaneous radio-frequency ablation is a minimally invasive treatment option for osteoid osteomas. The ablation process is straightforward in the more common locations like the femur/tibia. Surgery has historically been the gold standard, but is currently used in lesions, that may not be effectively and safely ablated, i.e. close to skin/nerve. Radio-frequency ablation can still be used in such cases along with additional techniques/strategies to protect the sensitive structures and hence improve the outcomes. The authors describe their experience with four challenging osteoid osteoma ablation cases.

Methods

We retrospectively reviewed radio-frequency ablations of four osteoid osteomas in rather atypical locations, the protective techniques/strategies employed, the adequacy and safety of the radio-frequency ablation with the use of these techniques.

Results

All patients had complete resolution of pain with no recurrence in the follow-up period. No complications were reported.

Conclusion

RFA has been proven to be an effective and safe option for treatment of OOs in the common locations. It is generally recommended to have a 1 cm safety margin between the RF probe and any critical structures in the vicinity. However, with OOs in atypical locations this may not be always possible and hence additional techniques may be needed to ensure protection of the surrounding sensitive structures and also allow for effective ablation.

Image-guided Percutaneous Radiofrequency Ablation for Osteoid Osteoma: Experience from a Developing Nation

Objective

The purpose of this study is to report our experience in using image-guided percutaneous radiofrequency ablation (RFA) for the treatment of osteoid osteoma (OO) and the subsequent duration of pain relief over a period of about six years (May 2013-March 2019; 70 months) at a tertiary-care hospital in a developing nation.

Methods

A retrospective study was performed at the radiology department of Aga Khan University, Karachi, Pakistan. All patients who had undergone image-guided percutaneous RFA for OO between May 2013-March 2019 were included. All cases had been performed with CT-guidance under general anesthesia, with an additional local anesthesia injection also administered to the patients. A soloist needle had been used for RFA. The primary success rates, complications, symptom-free intervals, and follow-ups were evaluated.

Results

In total, 15 patients (11 males, 4 females) of a mean age of 13.93 years (range: 5-25 years; median age: 14.5 years) with OO underwent image-guided percutaneous RFA during a period of 70 months. Eleven lesions were located in the femur, three in the tibia, and one in the humerus. The mean nidus size was 8.1 x 5.73 mm [range: (4.9-11.5) x (3.8-9.1) mm]. All patients were successfully treated and experienced resolution of pain in 2.36 months (range: 1-4 months). During the follow-up period (range: 3-40 months; mean: 13.85 months; median: nine months), none of the patients experienced any relapse or persistent symptoms. No major complications were reported.

Conclusion

Image-guided percutaneous RFA is a minimally invasive and safe treatment option with high efficiency and a high rate of technical success for the treatment of OO. The risk of recurrence is remote with all patients achieving independent recovery.

COMPARISON OF RADIOFREQUENCY ABLATION AND CURETTAGE IN OSTEOID OSTEOMA IN CHILDREN

Objective:

Osteoid osteoma, which is observed in the adolescent and young adult population as benign bone tumors, appears as a single nidus with a diameter < 2 cm and is treated with open surgery. However, technological advances in medicine have made it possible to apply less invasive procedures in surgery.

Methods:

Between 2006–2014, 24 patients < 18 years of age were treated for osteoid osteoma. Patient demographic data, surgical data, complications, and recurrences were noted.

Results:

Twenty-four patients (mean age, 11 [2–18] years) were treated and followed up for a mean 3.58 (range, 1–9) years. Mean patient age in the curettage group was 12.1 (range, 3–18) years. Mean operation length was 69.5 (range, 60–120) minutes. Mean hospital stay was 1.3 (range, 0–2) days. Mean patient age in the radiofrequency ablation (RFA) group was 10.7 (range, 2–17) years. Five patients were female and 8 were male. Mean operation length was 49.6 (range, 20–90) minutes. Mean hospital stay was 0.3 (range, 0–1) days. Mean follow-up time was 1.76 (range, 1–4) years. Mean operation length, hospital stay, and follow-up were significantly shorter in the RFA group.

Conclusions:

Considering reduced costs due to shorter hospitalization periods and the ability to reach anatomically difficult locations, percutaneous procedures are likely to replace the conventional open approach. Level of evidence: II, retrospective study.

Osteoid osteoma: Contemporary management

Osteoid osteoma is a benign bone-forming tumor with hallmark of tumor cells directly forming mature bone. Osteoid osteoma accounts for around 5% of all bone tumors and 11% of benign bone tumors with a male predilection. It occurs predominantly in long bones of the appendicular skeleton. According to Musculoskeletal Tumor Society staging system for benign tumors, osteoid osteoma is a stage-2 lesion. It is classified based on location as cortical, cancellous, or subperiosteal. Nocturnal pain is the most common symptom that usually responds to salicyclates and non-steroidal anti-inflammatory medications. CT is the modality of choice not only for diagnosis but also for specifying location of the lesion, i.e. cortical vs sub periosteal or medullary. Non-operative treatment can be considered as an option since the natural history of osteoid osteoma is that of spontaneous healing. Surgical treatment is an option for patients with severe pain and those not responding to NSAIDs. Available surgical procedures include radiofrequency (RF) ablation, CT-guided percutaneous excision and en bloc resection.

Radiofrequency ablation for osteoid osteoma - Recurrence rates and predictive factors

BACKGROUND AND PURPOSE

Osteoid osteoma is an infrequent but debilitating benign bone lesion which can be successfully managed by percutaneous radiofrequency ablation (RFA). There are few studies investigating the efficacy and follow-up of this treatment. An arbitrary upper limit of 15 mm has been used to differentiate between osteoid osteoma and osteoblastoma with surgery used for lesions above this limit. We aimed to analyse the cases identified from our prospectively maintained database over a ten year period since adoption of this technique in our unit. The primary objectives were to investigate factors which influenced recurrence and the time period at which patients are at risk of this.

BASIC PROCEDURES

Consecutive patients with confirmed osteoid osteoma were included. Patient demographics, complications, and recurrence were recorded and multiple regression analysis was performed to investigate causation.

MAIN FINDINGS

Within a minimum follow up of 21 months (mean 72), a recurrence rate of 16.3% was noted, higher than the published literature. Cox regression analysis to predict chance of recurrence revealed a relationship between larger lucent diameter and recurrence (p = 0.049, CI 95%, hazard ratio 1.33).

CONCLUSIONS

The traditional cut off between osteoid osteoma and osteoblastoma appears less rigidly defined than previously thought and probably represents a progressive scale with larger lesions responding less well to RFA. This study indicates that each millimetre increase represents a ×1.33 chance of recurrence. Clinicians should counsel patients accordingly with lesions approaching the larger limits of this diagnosis.

Proximal Phalanx Osteoid Osteoma: A Case Report and Literature Review

Osteoid osteoma is a rare clinical entity often mistaken for osteomyelitis, enchondroma, osteochondroma and other bony pathologies. Cardinal features include localized swelling and nocturnal pain often relieved by nonsteroidal antiinflammatory drugs. Definitive treatment requires surgical removal of the lesion by curettage or en bloc excision. The following case report details the diagnosis and management of a recurrent case of osteoid osteoma in a long finger proximal phalanx. Included with this case report is a literature review of osteoid osteomas on the hand and the anatomic distribution of 289 cases published in the last 30 years.

Osteoid osteoma - radiofrequency ablation treatment guided by computed tomography: a case series

The osteoid osteoma is a benign primary bone tumor that affects mainly males in the second and third decades of life. Radiographic findings show a radiolucent nidus surrounded by reactive sclerotic bone, particularly in the long bones of the lower extremity. Clinically, it presents persistent pain, which is worse at night and improves with salicylates. It can be a self-limiting injury, with an average duration of three years, but because of pain intensity and intolerance to prolonged use of nonsteroidal anti-inflammatories, surgical treatment is an option. The diagnosis is suspected according to the history and radiographic findings, and the confirmation is made by histological analysis. The traditional surgical treatment is the complete excision of the nidus, but some disadvantages have been described, such as difficulties in localizing the lesion and risk of fracture during the procedure, hospital stay for pain control, and unfavorable esthetic outcome. The authors report a series of cases treated with thermal radiofrequency ablation guided by computed tomography in this service. It is a safe and an effective percutaneous method that aims to cure, minimizing the trauma and morbidity when compared with the conventional block-resection method.

Osteoid osteoma of the acetabulum successfully treated with computed tomography-guided resection and ablation using a standard electrosurgical generator: a case report

Background

Osteoid osteoma accounts for approximately 10% of all benign bone tumors. The most common sites of osteoid osteoma are the subcortical shaft and metaphyses of long bones, but any other skeletal bone site can be involved. The acetabulum is a rare site according to past reports. This site presents challenges to optimal management because it is anatomically difficult to approach, and because its rarity leads to limited experience with therapeutic procedures. Here, we report for the first time a rare case of osteoid osteoma in the acetabulum that was successfully treated via resection of the nidus and ablation using a standard electrosurgical generator under computed tomographic guidance.

Case presentation

A 9-year-old Japanese girl presented at a clinic with left hip pain without apparent cause for 1 month. She was diagnosed as having coxitis simplex. However, her pain did not change for 1 year and she was admitted to another hospital where osteoid osteoma in her left acetabulum was suspected. She was then referred to our hospital approximately 1 year after first symptom presentation, where she presented with severe left hip pain and was completely unable to walk. Computed tomography examinations revealed a well-demarcated 5 mm mass with bone sclerosis in her left acetabulum. The mass was characterized by low intensity on T1 and high intensity on T2 magnetic resonance images. These findings were consistent with osteoid osteoma of left acetabulum. She underwent computed tomography-guided resection of nidus and ablation using a standard electrosurgical generator. A histological examination confirmed acetabular osteoid osteoma. Complete pain relief was achieved after the procedure and she experienced no complications. She could walk without any pain at the final follow-up 1 year post-treatment and no local recurrence was observed.

Conclusions

We successfully treated acetabulum osteoid osteoma without any symptom recurrence by computed tomography-guided resection and ablation using a standard electrosurgical generator. In addition, we preserved our patient’s sciatic nerve and triradiate cartilage. Our report provides evidence that a computed tomography-guided procedure should be considered the treatment of choice for osteoid osteoma of the acetabulum because it is a less invasive alternative to en bloc resection.

Intra-articular osteoid osteoma as a differential diagnosis of diffuse mono-articular joint pain

Background

The aim of this retrospective study was to investigate the frequency of intra-articular osteoid osteoma (iaOO) in a large study cohort and to demonstrate its clinical relevance as an important differential diagnosis of non-specific mono-articular joint pain.

Methods

We searched the registry for bone tumours of the University Medical Centre Hamburg-Eppendorf for osteoid osteomas in the last 42 years. Herein, we present three selected iaOO which were detected in the three major weight-bearing joints. Computed tomography (CT) or magnetic resonance imaging (MRI) scans were performed for initial diagnosis.

Results

Out of a total of 367 osteoid osteomas, 19 (5.2 %) tumours were localized intra-articularly. In all three presented tumours, a history of severe mono-articular pain was reported; however, the mean time to correct diagnosis was delayed to 20.7 months. Clearly, the nidus seen in CT and MRI images in combination with inconsistent salicylate-responsive nocturnal pain led to the diagnosis of iaOO.

Conclusions

Rarely, osteoid osteoma can occur in an intra-articular location. In cases of diffuse mono-articular pain, iaOO should be considered both in large and smaller joints to avoid delays in diagnosis and therapy of this benign bone tumour.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-1313-3) contains supplementary material, which is available to authorized users.

Effectiveness of Computed Tomography Guided Percutaneous Radiofrequency Ablation Therapy for Osteoid Osteoma: Initial Results and Review of the Literature

Background

The aim of this retrospective study is to determine our experience of technique success rate, complications and clinical results in long term follow up for computed tomography (CT)-guided radiofrequency ablation [RA] therapy for osteoid osteoma (OO).

Material/Methods

We performed RA therapy to 18 patients with OO referred to interventional radiology from other clinics primarily from orthopedics; between January 2011 to May 2014. Daytime and nighttime pain intensity of 18 patients was noted according to visual analog scale (VAS). After procedure pain intensity was compared with before one. We also discussed other factors can affect it.

Results

All procedures were completed technically successful for all patients [100%]. We did not experience any major complication or mortality. However we had 3 minor complications. Pain came back in 1 patient after 5 months from procedure and it was considered as recurrence. Dramatic pain intensity fall was seen in patients after procedure, both daytime and nighttime. However we did not find and statistically significant change in comparison of pain intensity reduce and time needed to return back to routine life when using patients demographic data and lesion size.

Conclusions

CT guided RA therapy of OO is minimally invasive, effective and secure procedure.

Osteoid osteoma of the foot and ankle--A systematic review

BACKGROUND

Osteoid osteomas are responsible for 10% of benign bone tumours. Treatment typically involves surgical excision or radio frequency ablation. The aim of this systematic review is to evaluate reported cases of foot and ankle osteoid osteomas.

METHODS

We conducted a systematic review of the literature using the online databases Medline and EMBASE. We included studies reporting osteoid osteoma diagnosed either radiologically or histologically.

RESULTS

94 studies were included reporting 223 cases; 70.5% were male, mean age was 23 years, 69% reported night pain and 72% responded to NSAIDs. The commonest affected bone was the talus. CT scan was the most useful radiological investigation and MRI missed the diagnosis in 34% of cases. The majority of patients underwent surgical excision but an increasing trend of ablation therapy was demonstrated.

CONCLUSIONS

A high index of suspicion based on salient history and appropriate imaging are essential for timely identification and treatment.

Arthroscopic excision of acetabular osteoid osteoma in a 7-year-old patient

The purpose of this study was to present the case report of a 7-year-old patient who was treated with hip arthroscopy for an acetabular osteoid osteoma. A 7-year-old patient was referred to our clinic with hip pain. In the assessment of the patient, an acetabular osteoid osteoma was detected in his right hip; it was adjacent to his triradiate cartilage. An arthroscopic surgery was planned as an alternative to open safe hip dislocation. The osteoid osteoma was completely removed with hip arthroscopy. Postoperative CT scanning and histopathological analysis confirmed the diagnosis. Exposure of the acetabulum can be problematic in paediatric patients due to the potential risks of open safe dislocation. Hip arthroscopy can safely be used for benign hip lesions in paediatric patients. Level of evidence Case report, Level V.

Hip arthroscopy for the management of osteoid osteoma of the acetabulum: a systematic review of the literature and case report

Background

Intra-articular osteoid osteoma (OO) causes irreversible joint damage. Its treatment of choice is radiofrequency ablation (RFA); however, some areas of the acetabulum are hard to access. Therefore, hip arthroscopy was used to treat this tumor. We aim to systematically review the literature with regards to arthroscopic management of acetabular OO, and to report a further case in which hip arthroscopy was used for treatment.

Methods

PubMed and EMBASE were searched for articles relevant to the arthroscopic management of acetabular OO on December 2, 2014. All articles published on and before that date were reviewed, and studies which met our pre-determined inclusion criteria were included. Articles screening and data abstraction were done by two reviewers independently. We also presented a 31-year-old man with acetabular OO who underwent hip arthroscopy for the management of his tumor after failing to respond to medications and computed tomography scan (CT)-guided RFA.

Results

The initial search revealed 14 studies, of which ten met our inclusion criteria. A total of ten patients underwent hip arthroscopy for the management of acetabular OO. Only two patients were females, and the patients' age ranged from 7 to 47 years. Two patients underwent arthroscopic guided-RFA of the lesion, while the rest underwent excision. The follow-up period ranged from 6 months to 2 years. Success rate was 100 %, and no recurrence was reported. Minor complications (transient impotence and perineal numbness) developed in one patient (10 %). Arthroscopic-guided RFA failed to eliminate the tumor in our additional case. A second trial of CT-guided RFA was successful in treating the patient's condition.

Conclusions

Hip arthroscopy is an effective and safe option for the management of acetabular OO, with success rate exceeding 90 %. Studies of higher level of evidence are required.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-015-0779-8) contains supplementary material, which is available to authorized users.

Osteoid osteoma treated with radiofrequency ablation

Purpose. Our aim is to evaluate the results of treatment with computed tomography (CT) guided percutaneous radiofrequency ablation for osteoid osteomas which were localized in a difficult area for operation. Materials and Methods. Glenoid, distal tibia, humerus shaft, proximal humerus, and in third finger of the hand proximal phalanx were involved in one patient. Proximal femur was involved in three patients, distal femur was involved in three patients, and proximal tibia was involved in two patients. 9 males and 4 females were aged 4 to 34 years (mean age: 18.5 years). All patients had pain and were evaluated with X-rays, CT, bone scintigraphy, and MRI. In all patients, RF ablation was performed with local anesthesia. The lesion heated to 90°C for 6 minutes. Results. All of the patients achieved complete pain relief after ablation and were fully weight bearing without any support. In all patients, there was soft tissue edema after the procedure. During follow-up, all patients were free from the pain and there was no sign about the tumor. There was no other complication after the process. Conclusion. CT guided RFA is a minimally invasive, safe, and cost-effective treatment for osteoid osteoma placed in difficult area for surgery.

Radiofrequency thermal ablation of osteoid osteomas of the proximal femur. Usefulness of ultrasound guidance in selected cases

PURPOSE

To review symptoms and imaging findings of proximal femoral osteoid osteomas (OO); to analyse the results of a thermal ablation technique for radiofrequency of the nidus in this location; and to describe usefulness of ultrasound guidance in selected cases.

MATERIAL AND METHOD

Descriptive and retrospective study consisting of 8 patients with OO in the proximal epiphysis of the femur, which were treated by thermal ablation of the nidus with radiofrequency waves from 1998 to 2004.

RESULTS

The mean pain period until the performance of the thermal ablation was 11.5 months (range 5-18 months). There were no complications, and all patients stated that the pain was gone by the day following the procedure, with some discomfort during the first week, except for one where it lasted more than one month due to technique difficulties. At present, with a mean follow up of 6 years and 2 months (range 6-190 months), all patients remain asymptomatic and live a rigorous normal life.

DISCUSSION

Thermal ablation with CT-guided radiofrequency waves is a safe, effective and efficient procedure.

CONCLUSION

Normal appearance of a proximal femoral OO does not differ significantly from other location osteomas and its diagnosis is easier with previous knowledge. Thermal ablation of the nidus with radiofrequency waves, that may be performed using ultrasound guidance, appears to be the elective treatment of choice due to its efficiency and minimum morbidity.

Osteoid osteoma treated by percutaneous thermal ablation: when do we fail? A systematic review and guidelines for future reporting

PURPOSE

Osteoid osteoma (OO) is a painful benign bone tumor of the young that is widely treated by percutaneous thermal ablation (PTA) with success rates close to 100%. Nevertheless, some patients have recurrences. We reviewed the literature to understand whether these are true recurrences or incomplete treatments; to analyze safety and efficacy during long-term follow-up in a extremely large cohort of patients; to detail best-practice suggestions from the largest clinical trials as well as report their complications; and to recommend standards for future reporting.

MATERIALS AND METHODS

This study followed the Cochrane's guidelines for Systematic Reviews of Interventions. Inclusion criteria were as follows: (1) prospective or retrospective cohort study for PTA of OO under computed tomography (CT) guidance; (2) CT or magnetic resonance diagnosis; (3) radiofrequency ablation or interstitial laser ablation technique; (4) English language; (5) population <10 patients; (6) follow-up ≥12 months; and (7) original research. Risk of bias was assessed with a modified Newcastle-Ottawa Scale.

RESULTS

Two hundred fourteen articles were initially found. After applying the criteria mentioned previously, 27 PTA articles concerning 1,772 patients were chosen for inclusion. No exclusions were made due to risk of bias.

CONCLUSION

The investigators proved the long-term efficacy and superiority of PTA for OO compared with other techniques. In 5% of patients, however, the technique failed, and the researchers did not offer detailed exhaustive explanations. Future clinical trials for OO ablation should consider reporting essential procedure details and follow-up findings to allow for a meta-analysis. We provide both recommended standards for future reporting and suggestions for the prevention of recurrence.

Osteoid osteoma

Osteoid osteomas consist of a nidus with surrounding sclerotic bone. The differential diagnosis covers a wide range of conditions due to the variable presentation of osteoid osteoma. The natural history is for regression to occur within 6 to 15 years with no treatment; however, this can be reduced to 2 to 3 years with the use of aspirin and non-steroidal anti-inflammatory drugs. Computed tomography-guided percutaneous techniques, including trephine excision, cryoablation, radiofrequency ablation, and laser thermocoagulation, are described.

Osteoid osteoma of the acetabular fossa: five cases treated with percutaneous resection

BACKGROUND

Osteoid osteoma is a painful benign osteogenic tumour for which the treatment objective is surgical resection of the nidus. The acetabular fossa is an uncommon site of involvement where surgical access can prove challenging.

MATERIALS AND METHODS

We report a case-series composed of five patients with osteoid osteoma of the acetabular fossa treated with percutaneous bone resection and drilling under computed tomography guidance.

RESULTS

All five patients had an uneventful postoperative course with immediate pain relief that was sustained over time.

DISCUSSION

The outcomes achieved using our percutaneous technique compare favourably with those of other percutaneous methods, most notably regarding pain relief and patient tolerance of the procedure.

CONCLUSION

Percutaneous bone resection and drilling under computed tomography guidance proved effective for the treatment of osteoid osteoma involving the acetabular fossa.

LEVEL OF EVIDENCE

Level IV.

Case report: Osteoid osteoma of the acetabulum treated with arthroscopy-assisted radiofrequency ablation

BACKGROUND

Osteoid osteomas consist of a nidus surrounded by reactive sclerotic bone. The diagnosis typically is based on imaging and clinical presentation involving nocturnal pain. Removal of the lesion is essential and currently is performed mainly with image-guided, minimally invasive techniques. We describe a case involving an osteoid osteoma of the acetabular fossa, treated with arthroscopy-assisted radiofrequency ablation.

CASE DESCRIPTION

A 47-year-old woman presented with a 9-month history of right groin pain and limited motion. The CT and MR images showed synovitis around the ligamentum teres and a nidus of the acetabular fossa, surrounded by sclerotic bone and protruding from the inner part of the lamina quadrilateral. Synovectomy and debridement of the ligamentum teres were performed, followed by radiofrequency ablation of the osteoid osteoma under direct arthroscopic observation of the hip, avoiding resection of the normal bone around the nidus and preserving the integrity of the quadrilateral lamina and cartilage. The patient had complete pain relief the next day with minimal morbidity and rapid functional restoration. At the 22-month clinical followup, the patient was asymptomatic, and the CT and MR images obtained 1 year after surgery showed no pathologic signs or synovitis.

LITERATURE REVIEW

Our case was the fifth such case to be treated with hip arthroscopy and the first of these to our knowledge to be treated with the arthroscopy-assisted radiofrequency ablation technique.

PURPOSES AND CLINICAL RELEVANCE

Arthroscopy-assisted radiofrequency ablation is a combined treatment technique that may be used for intraarticular lesions of the hip that otherwise would require a difficult approach and jeopardize damage to cartilage and bone and also treat concomitant synovitis.

Osteoid osteoma mimicking triangular fibrocartilage complex injury: diagnosis and review of treatment

We report the case of osteoid osteoma (OO) with ulnar styloid involvement. A review of the literature has been made with the aim of defining the special behaviour of OO when it is near the articular surface. That behaviour can affect the diagnosis, masking the real etiology of the pain, delaying the diagnosis, missing the diagnosis, or what is more serious, conducting an inadequate treatment. We propose a treatment algorithm conducted based on the localization near or far from articular surface and the superficial or deep localization.

CT-guided radiofrequency ablation of osteoid osteoma in the long bones of the lower extremity

AIM: To present our initial experience with computed tomography guided radiofrequency ablation (RFA) of osteoid osteoma (OO) in our institution.

METHODS: RFA was performed on eight patients (5 males and 3 females) with clinically and radiologically diagnosed OO (femoral neck, n = 4; femoral diaphysis, n = 2; tibial diaphysis, n = 1; fibular diaphysis, n = 1). Ablation was performed using an electrode with a 10-mm exposed tip for a total of 4-6 min at a targeted temperature of 90 degrees Celsius. No cooling system was used. The intervention was accepted as technically successful if the tip of the electrode could be placed within the center of the nidus. We defined clinical success as a disappearance within 2 wk after treatment of symptoms that had manifested at presentation.

RESULTS: All procedures were technically successful. No major or immediate complications were observed. Clinical success was achieved in six of eight patients in the first procedure. A second procedure was performed for two patients who had recurrent or continued pain, and one of these cases was successfully treated. The overall rate of success was 87.5% (7/8). No complication was observed.

CONCLUSION: Our preliminary results indicate a favorable success rate and no complications and are compatible with the previous reports of RFA of OO.

OSTEOID OSTEOMA IN THE ILIAC BONE: REPORT ON TWO CASES

Osteoid osteoma is a benign bone tumor that generally presents with nighttime pain among young adults and is relieved by rest and salicylates. It can affect any bone, but occurrences in the iliac are unusual. The authors describe two cases of intramedullary osteoid osteoma next to the sacroiliac joint, with symptoms that simulated sciatic pain. The cases were diagnosed late, although the initial radiographs showed sclerotic lesions in both cases. The diagnosis was confirmed by means of CT scan and the nidus was excised surgically through en bloc resection. The definitive diagnosis was given by means of histopathological examination. Over long-term follow-up, both cases remained asymptomatic and complete bone remodeling at the surgical site was observed. The authors highlight the typical characteristics of the tumor, the unusual location, the differential diagnosis and the treatment.