Histological evaluation of drill fragments obtained during osteoid osteoma radiofrequency ablation

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.

CT-guided radiofrequency ablation of osteoid osteoma using a multi-tined expandable electrode system

BACKGROUND AND AIM OF THE WORK

Radiofrequency ablation (RFA) is the gold standard for the treatment of symptomatic osteoid osteoma (OO) as RFA yields both a high success and low complication rate. It has been widely utilized over the years, but recurrences of OO after this treatment have been documented. These recurrences may be the result of various factors, including incomplete tumor ablation, and are significantly higher in lesions greater than 10 mm. Thus, the need to induce thermal ablation in a wider area led us to use a Multi-Tined Expandable Electrode System (MTEES). In this study we examined the efficacy and safety of RFA using a MTEES in symptomatic OO.

METHODS

Between January 2005 and June 2007, 16 patients with symptomatic OO were treated by CT-guided percutaneous RFA using a MTEES. The diameter of OO ranged from 6 to 15 mm (mean 10±2.6 mm). Patients were evaluated for clinical outcomes, complications and recurrence. Pain evaluation was assessed preoperatively, 2 weeks postoperatively and at last follow-up.

RESULTS

Clinical follow-up was available for all patients at a mean of 84.3 months (range 73-96 months). Mean preoperative VAS score was 7.4 (range 5-9), two weeks after the procedure mean VAS score was 0.3 (range 0-1) with a mean change of -7.06 points (p<0.0001). At the last follow-up a complete relief from pain has been observed in all patients. No major and minor complications were observed nor recurrences.

CONCLUSIONS

RFA using a MTEES has been effective, safe and reliable for the treatment of OOs. This system, by increasing the size of the necrosis, could be a viable alternative to the single needle electrode in lesions larger than 10 mm, reducing the risk of recurrence.

Open Surgery for Osteoid Osteoma with Three Dimensional C-arm Scan under the Guidance of Computer Navigation

OBJECTIVE

To evaluate the clinical outcomes of open surgery for osteoid osteoma with three-dimensional (3-D) C-arm scan under the guidance of computer navigation.

METHODS

The clinical data of 14 patients who had undergone 3-D C-arm scan under the guidance of computer navigation during open surgery for osteoid osteoma from March 2012 to June 2015 were analyzed retrospectively. There were nine male and five female subjects aged from 9 to 55 years (mean, 26 years). Eight of the tumors were located in the femur, four in the tibia, one in the humerus and one in the scapula. Preoperative pain visual analogue scale (VAS) scores ranged from 2 to 6 (mean ± SD, 4.7 ± 1.1). Conventional surgical approaches were used to expose the tumor surfaces depending on their locations. Involved regions were scanned by 3-D C-arm fluoroscopy during the procedure and then the tumors were accurately located and their niduses removed under the guidance of computer navigation. Afterwards, repeat 3-D C-arm scans of the surgical region were performed to confirm tumor eradication. None of the patients received postoperative intravenous analgesia. Eight patients received oral non-steroidal anti-inflammatory drugs on the day of surgery, these drugs being discontinued on the second postoperative day. Postoperative pathological diagnoses were recorded. At the follow-up visits, imaging and VAS scores were obtained to evaluate the therapeutic effect and any evidence of recurrence.

RESULTS

All the patients successfully underwent computer navigation-guided surgery. The duration of surgery ranged from 60 to 135 min (mean, 94 min) and the amount of bleeding from 50 to 150 mL (mean, 80 mL). None of the patients needed bone grafting or internal fixation. No complications were seen. All patients were followed up for 4 to 36 months (mean, 16 months). Postoperative pathological diagnoses of osteoid osteoma were made in 12 patients; thus, the rate of pathologically confirmed diagnosis was 86%. VAS scores decrease to an average of 1.4 ± 0.6 3 days after surgery and were zero for all patients 4 months after surgery. No tumor recurrence was found by X-ray or CT scan examination during follow-up.

CONCLUSIONS

The niduses of osteoid osteomas can be eradicated by open surgery with 3-D C-arm scan under the guidance of computer navigation with minimal damage to bone structure and a high rate of pathologically confirmed diagnoses.

CT-guided radiofrequency ablation of osteoid osteoma using a novel battery-powered drill

OBJECTIVE

To evaluate the use of a novel battery-powered drill, enabling specimen requirement while drilling, in radiofrequency ablation of osteoid osteoma as an alternative to conventional orthopedic drills.

MATERIALS AND METHODS

Between 2009 and 2013, altogether 33 patients underwent CT-guided radiofrequency ablation of an osteoid osteoma at our institution. To access the nidus of the clinically and radiologically suspected osteoid osteoma, a channel was drilled using the OnControl Bone Marrow Biopsy System (OBM, Arrow OnControl, Teleflex, Shavano Park, TX, USA) and a biopsy was taken. Procedure time (i.e., drilling including local anesthesia), amount of scans (i.e., single-shot fluoroscopy), radiation exposure, and the results of biopsy were investigated and compared retrospectively to a classical approach using either a manual bone biopsy system or a conventional orthopedic drill (n = 10) after ethical review board approval.

RESULTS

Drilling the tract into the nidus was performed without problems in 22 of the 23 OBM cases. Median procedure time was 7 min compared to 13 min using the classical approach (p < 0.001). Median amount CT scans, performed to control correct positioning of the drill was comparable with 26 compared to 24.5 (p = NS) scans. Histologically, the diagnosis of osteoid osteomas could be determined in all 17 cases where a biopsy was taken. Radiofrequency ablation could be performed without problems in any case.

CONCLUSIONS

The use of the battery-powered drill was feasible and facilitated the access to the osteoid osteoma's nidus offering the possibility to extract a specimen in the same step.

Treatment of osteoid osteoma with CT-guided percutaneous radiofrequency thermoablation

Osteoid osteoma is a benign bone tumor with a male predominance occurring mainly in children and young adults. The most common symptom is intermittent pain that worsens at night and is at least partially relieved by nonsteroidal anti-inflammatory drugs. The purpose of this study was to assess the long-term effectiveness of computed tomography-guided percutaneous radiofrequency thermoablation in patients with a minimum follow-up of 2 years. Twenty patients with osteoid osteoma (15 men and 5 women) with a mean age of 20.7 years (range, 4-61 years; 12 patients aged 20 years or younger) underwent computed tomography-guided percutaneous radiofrequency thermoablation. Lesion sites were the femur (n=9), tibia (n=7), pelvis (n=1), talus (n=1), cuneiform bone (n=1), and humerus (n=1). Mean follow-up was 44 months (range, 3-106 months). Pain relief was significant in 95% of patients; it disappeared within 24 hours in 14 patients, within 3 days in 4, and within 7 days in 1. The patient with persistent symptoms underwent another percutaneous radiofrequency thermoablation procedure that was successful. The difference between pre- and postoperative pain was significant (P ≤ .01). No recurrences occurred. Computed tomography-guided percutaneous radiofrequency thermoablation is a safe, minimally invasive, and economical procedure with high technical and clinical success rates, and it effectively and durably enhances quality of life.

Interstitial laser photocoagulation for the treatment of osteoid osteoma: retrospective study on 35 cases

PURPOSE

The aim of our retrospective study was to evaluate the efficacy of interstitial laser photocoagulation for the treatment of osteoid osteomas and to identify the factors leading to failure of the procedure.

MATERIAL AND METHODS

Thirty-five patients received interstitial laser photocoagulation treatment. A minimum of 3 months follow-up was required. The laser fibre was positioned within the nidus under CT guidance, and energy between 500 and 1800 J was delivered at a power of 2 Watts/s. Follow-up was by outpatient appointment and through a questionnaire sent to the patients.

RESULTS

Thirty patients replied to the questionnaire. Mean follow-up was 40 months. The technical success rate was 100%. The primary success rate (no pain at 1 month) was 94.3%. The rate of recurrence was 6%. The rate of complications was 11.4% (a skin burn, patellar enthesopathy, a broken item of material, sacro-iliac fibrous alterations). Factors likely to favour failure of the procedure are the size of the nidus (P=0.04) and poor positioning of the laser fibre (P=0.03).

CONCLUSION

Interstitial laser photocoagulation is an effective and safe treatment for osteoid osteomas.

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.

Follow-up of thirty-three computed-tomography-guided percutaneous radiofrequency thermoablations of osteoid osteoma

PURPOSE

This study aimed to determine the mid- and long-term success and complication rates of radiofrequency ablation (RFA) in treatment of osteoid osteoma (OO). Furthermore we were interested in the value of bone biopsy when using a core-drill before the radiofrequency ablation.

METHODS

We retrospectively analysed data of 33 patients (33 osteoid osteomas, 22 males, 11 females) who underwent computed-tomography (CT) guided radiofrequency ablation between 1998 and 2005. The patients had a mean age of 20 years (range, five to 50 years). They were monitored for a mean follow-up of 92 months (range, 60-121 months).

RESULTS

Lesions were located as follows: 11 cases in the proximal femur, five in the femoral shaft, six in the tibia, one in the calcaneus, two in the metatarsals (second and fourth metatarsals), one in the os cuneiforme mediale, six in the humeral and one in the ulnar shaft. Within the presented time frame 32 of 33 patients were successfully treated and had no more complaints. In one of 33 patients relapse occurred after 28 months and RFA was repeated. There were no complications associated with the procedure. Biopsy obtained prior to thermocoagulation with the help of a core-drill was able to prove diagnosis in all patients (100%).

CONCLUSIONS

These results indicate that the presented technique of CT guided RFA combined with the use of a core-drill for biopsy prior to RFA treatment is a highly effective, efficient, minimally invasive and safe method for the treatment of OO, yielding a success rate of 97% combined with a 100% histological verification of the diagnosis after a minimum follow-up period of five years.