O-Arm-Navigated, Robot-Assisted Versus Conventional CT Guided Radiofrequency Ablation in Treatment of Osteoid Osteoma: A Retrospective Cohort Study

Computer-navigated, stereotactic navigation for percutaneous radiofrequency ablation of osteoid osteomas: dose comparison and procedure times

PURPOSE

Treatment of medication-refractory osteoid osteoma is typically performed with minimally-invasive percutaneous techniques, such as radiofrequency ablation. Given the typically young age of the population of patients being treated, we sought to assess whether using a 3D CT guidance system reduces the number of required probe repositionings and the number of required CTs to validate probe positioning in order to reduce the radiation dosage to the patient.

METHODS

We retrospectively reviewed the records of 19 patients who underwent procedures at our clinic amounting to a total of 27 ablations between 2012 and 2022. At the time of each procedure, the operating physician made the decision whether or not to use stereotactic navigation assistance. We analyzed the data using a Bayesian approach to elucidate possible differences between procedures conducted with or without navigation.

RESULTS

Our results showed a statistically and clinically-significant administration of, on average, 200 mGy*cm greater radiation dosage to the patient when stereotactic navigation was used to guide RFA probe placement for ablation of osteoid osteomas compared with not using navigation assistance. There was a trend towards requiring one fewer probe repositioning with navigation assistance, however this was not statistically conclusive. There was no difference in the time required to achieve the target probe placement or in total procedure duration whether stereotactic navigation was used or not.

CONCLUSION

When utilizing a 3D-guided stereotactic navigation system, there is likely a learning phase before the potential benefits of such a system are realized. Additional radiation administration to the patient may result from the operator learning to properly use and trust the system. In our case, the data also likely reflect a bias in operator choice to use the navigation system when the lesions are more difficult to correctly target or multiple ablation positions are necessary, while choosing conventional imaging assistance for easily targetable tumors, which may conceal some of the benefit of using the navigation system.

Robot-assisted Percutaneous Radiofrequency Ablation for the Treatment of Osteoid Osteomas

OBJECTIVE

Percutaneous CT-guided radiofrequency ablation (CT-RFA) is a widely accepted procedure for treatment of osteoid osteomas. However, the application of CT-RFA was restricted as a result of some drawbacks, such as radiation exposure, and inconvenience in general anesthesia. The primary aim of this study is to evaluate the safety and efficacy of intra-operative TiRobot-assisted percutaneous RFA of osteoid osteomas.

METHODS

We retrospectively reviewed 21 medical files of patients who were treated with percutaneous RFA of osteoid osteomas guided by the TiRobot system in our institution between March 2021 and April 2022. The three-dimensional images obtained by a 3D C-arm intra-operatively were sent to the TiRobot system. The puncture point and trajectory were designed. Then the guide pin was positioned to the lesion with the assistance of TiRobot and the biopsy sheath was inserted into the lesion through the guide pin. The tumor was biopsied for pathological examination. Then the RFA needle was inserted into the nidus through the biopsy sheath for thermal ablation. Data were extracted on the associated complications, the reduction in pain at 1 month and 1 year postoperatively assessed by the visual analogue scale (VAS). A paired t-test was used to compare the pre-operative and post-operative VAS scores.

RESULTS

The patients included 17 males and four females with a mean age of 19.5 ± 10.4 years (range 3-45 years). Lesions were located on the femur in nine cases, on the tibia in nine cases, on the humerus in one case, on the calcaneus in one case, and on the acetabulum in one case. TiRobot-assisted percutaneous RFA was successfully performed on all 21 patients. There was no intra-operative or post-operative complications observed. Pathological diagnosis of osteoid osteoma was obtained in 11 patients, but the other 10 cases were not pathologically diagnosed. The mean follow-up time was 18.8 months (range: 12-26 months).Post-operative VAS scores were reduced significantly in all cases. The mean VAS score decreased from 6.5 pre-operatively to 0.5 at 1 month post-operatively and to 0.1 at 1 year post-operatively.

CONCLUSION

As a reliable technique for localizing and resection of nidus, TiRobot-assisted percutaneous RFA is a safe and effective option for the treatment of osteoid osteomas.

[Comparative study of orthopaedic robot-assisted minimally invasive surgery and open surgery for limb osteoid osteoma]

Objective

To compare the accuracy and effectiveness of orthopaedic robot-assisted minimally invasive surgery versus open surgery for limb osteoid osteoma.

Methods

A clinical data of 36 patients with limb osteoid osteomas admitted between June 2016 and June 2023 was retrospectively analyzed. Among them, 16 patients underwent orthopaedic robot-assisted minimally invasive surgery (robot-assisted surgery group), and 20 patients underwent tumor resection after lotcated by C-arm X-ray fluoroscopy (open surgery group). There was no significant difference between the two groups in the gender, age, lesion site, tumor nidus diameter, and preoperative pain visual analogue scale (VAS) scores ( P>0.05). The operation time, lesion resection time, intraoperative blood loss, intraoperative fluoroscopy frequency, lesion resection accuracy, and postoperative analgesic use frequency were recorded and compared between the two groups. The VAS scores for pain severity were compared preoperatively and at 3 days and 3 months postoperatively.

Results

Compared with the open surgery group, the robot-assisted surgery group had a longer operation time, less intraoperative blood loss, less fluoroscopy frequency, less postoperative analgesic use frequency, and higher lesion resection accuracy ( P<0.05). There was no significant difference in lesion resection time ( P>0.05). All patients were followed up after surgery, with a follow-up period of 3-24 months (median, 12 months) in the two groups. No postoperative complication such as wound infection or fracture occurred in either group during follow-up. No tumor recurrence was observed during follow-up. The VAS scores significantly improved in both groups at 3 days and 3 months after surgery when compared with preoperative value ( P<0.05). The VAS score at 3 days after surgery was significantly lower in robot-assisted surgery group than that in open surgery group ( P<0.05). However, there was no significant difference in VAS scores at 3 months between the two groups ( P>0.05).

Conclusion

Compared with open surgery, robot-assisted resection of limb osteoid osteomas has longer operation time, but the accuracy of lesion resection improve, intraoperative blood loss reduce, and early postoperative pain is lighter. It has the advantages of precision and minimally invasive surgery.

[Short-term effectiveness of orthopedic robot-assisted resection for osteoid osteoma]

Objective

To investigate short-term effectiveness and clinical application advantages of orthopedic robot-assisted resection for osteoid osteoma compared with traditional open surgery.

Methods

A retrospective analysis was conducted on clinical data of 48 osteoid osteoma patients who met the selection criteria between July 2022 and April 2023. Among them, 23 patients underwent orthopedic robot-assisted resection (robot-assisted surgery group), and 25 patients received traditional open surgery (traditional surgery group). There was no significant difference ( P>0.05) in gender, age, disease duration, lesion location and size, and preoperative visual analogue scale (VAS) score, and musculoskeletal tumor society (MSTS) score between the two groups. The surgical time, intraoperative blood loss, intraoperative lesion localization time, initial localization success rate, infection, and recurrence were recorded and compared. VAS scores before surgery and at 24 hours, 1, 3, 6, and 9 months after surgery and MSTS score before surgery and at 3 months after surgery were assessed.

Results

All patients completed the surgery successfully, with no significant difference in surgical time between the two groups ( P>0.05). Compared to the traditional surgery group, the robot-assisted surgery group had less intraoperative blood loss, shorter lesion localization time, and shorter hospitalization time, with significant differences ( P<0.05). The initial localization success rate was higher in the robot-assisted surgery group than in the traditional surgery group, but the difference between the two groups was not significant ( P>0.05). All patients in both groups were followed up, with the follow-up time of 3-12 months in the robot-assisted surgery group (median, 6 months) and 3-14 months in the traditional surgery group (median, 6 months). The postoperative MSTS scores of both groups improved significantly when compared to those before surgery ( P<0.05), but there was no significant difference in the changes in MSTS scores between the two groups ( P>0.05). The postoperative VAS scores of both groups showed a gradually decreasing trend over time ( P<0.05), but there was no significant difference between the two groups after surgery ( P>0.05). During follow-up, except for 1 case of postoperative infection in the traditional surgery group, there was no infections or recurrences in other cases. There was no significant difference in the incidence of postoperative infection between the two groups ( P>0.05).

Conclusion

Orthopedic robot-assisted osteoid osteoma resection achieves similar short-term effectiveness when compared to traditional open surgery, with shorter lesion localization time.

Accuracy of bony resection under computer-assisted navigation for bone sarcomas around the knee

BACKGROUND

Computer-assisted navigation has made bone sarcoma resections more precise. However, further clinical studies involving accuracy analyses under navigation are still warranted.

METHODS

A retrospective study for analysis of computer-assisted navigation accuracy was carried out. Between September 2008 and November 2017, 39 cases of bone sarcomas around the knee joint were resected under computer-assisted navigation. The control group comprised 117 cases of bone sarcomas around the knee treated by limb salvage surgery wherein bony cutting was achieved freehand. The length difference (LD) was defined as the specimen length minus the planned resection length. The LDs were detected in both groups and compared. The margin accuracy (MA) was defined as the achieved margin minus the desired margin at the bone cutting site and was detected in the navigation group.

RESULTS

The LDs between the postoperative specimen length and the preoperative planned length were compared. In the navigation group, the LD was 0.5 ± 2.5 mm (range, - 5 to 5 mm), while in the freehand group, the LD was 3.4 ± 9.6 mm (range, - 20 to 29 mm), with a significant difference (P < 0.01). In the absolute value analysis, the LD absolute value was 2.0 ± 1.6 mm in the navigation group and 8.3 ± 6.0 mm in the freehand group, with a significant difference (P < 0.01). In the navigation group, the MA was 0.3 ± 1.5 mm (range, - 3 to 3 mm) and the MA absolute value was 1.1 ± 1.0 mm.

CONCLUSIONS

Better accuracy can be achieved when computer-assisted navigation is conducted for bone sarcoma resection around the knee.

LEVEL OF EVIDENCE

IV.