Minimally Invasive Treatment for Unicameral Bone Cysts with Chemical Sclerosis and Bone Graft Substitute: A Preliminary Report

Use of regional anesthesia within a pediatric interventional radiology suite reduced periprocedural opioid use without delaying the overall workflow: a retrospective study

BACKGROUND

Nerve block utility has been extensively described in the operating room, however, there is a paucity of evidence regarding blocks in the interventional radiology (IR) suite, with no studies examining its safety and efficacy in children.

METHODS

A retrospective study was conducted at a single tertiary-care children's hospital to evaluate the analgesic utility of nerve blocks during IR-performed sclerotherapy for bone cysts, venous malformations, and lymphatic malformations. Lymphatic and venous malformations were combined for final analysis. Patients between January 2016 and September 2022 had their medical records reviewed for procedural data, postprocedural pain scores, and analgesic administration data.

RESULTS

309 patients were included in the final analysis. Opioids were required significantly less frequently intraprocedurally and postprocedurally across subgroups. The proportion of patients who received opioids during their hospital course was significant between block and non-block patients, respectively: bone cyst: 62.7% vs 100% (p<0.001); venous and lymphatic malformation: 65.7% vs 97.4% (p<0.001). Average maximum postanesthesia care unit (PACU) pain scores were significantly lower in bone cyst patients with no significant difference seen in pain scores among venous and lymphatic malformation patients. There were no reported nerve block-related complications.

DISCUSSION

Nerve blocks demonstrated an opioid-sparing effect intraprocedurally and postprocedurally for all subgroups. Their use among bone cyst patients was associated with significant reductions in average maximum PACU pain scores. Nerve blocks may constitute an effective opioid-sparing component of multimodal analgesia in pediatric patients undergoing IR sclerosis procedures. Prospective data are needed to establish the optimal utility of nerve blocks in the IR setting.

Percutaneous microwave ablation, perfusion, and reconstruction combined with a synthetic bone substitute in symptomatic bone cysts: a minimum of 26 months follow-up

PURPOSE

The objective was to describe the technique and clinical outcome of microwave thermal ablation (MWA) and perfusion combined with synthetic bone substitutes in treating unicameral bone cysts (UBCs) in adolescents.

MATERIALS AND METHODS

A total of 14 consecutive patients were enrolled by percutaneous MWA and saline irrigation combined with synthetic bone substitutes. Clinical follow-up included the assessment of pain, swelling, and functional mobility. Radiological parameters included tumor volume, physis-cyst distance, cortical thickness of the thinnest cortical bone, and the Modified Neer classification system.

RESULTS

The mean follow-up was 28.9 months (26-52 months). All UBCs were primary, and all patients underwent the MWA, saline perfusion, and reconstruction combined with a synthetic bone substitute session, except for one patient (7.1%) who required a second session. All patients had good clinical results at the final follow-up. Satisfactory cyst healing was achieved in 13 cases according to radiological parameters. Tumor volume decreased from a mean of 49.7 cm3 before surgery treatment to 13.9 cm3 at the final follow-up (p < 0.01). The physis-cyst distance increased from a mean of 3.17-4.83 cm at the final follow-up (p < 0.01). Cortical thickness improved from a mean of 1.1 mm to 2.0 mm at the final follow-up (p < 0.01). According to the proposed radiological criteria, our results were considered successful (Grading I and II) in 13 patients (92.9%) at the final follow-up.

CONCLUSION

Percutaneous microwave ablation combined with a bone graft substitute is a minimally invasive, effective, safe, and cost-effective approach to treating primary bone cysts in the limbs of adolescents.

Treatment of Unicameral Bone Cysts Utilizing the Sclerograft™ Technique

PURPOSE

To evaluate the Sclerograft™ procedure, which is an image-guided, minimally invasive approach of chemical sclerotherapy followed by bone grafting of unicameral bone cysts (UBC).

MATERIALS AND METHODS

A retrospective evaluation from August 2018 through August 2023 was performed at a single institution on patients that underwent the Sclerograft™ procedure for UBCs. Radiographic healing was evaluated utilizing the Modified Neer Classification. Two different regenerative grafts, CaSO4-CaPO4 and HA-CaSO4 were utilized. A total of 50 patients were evaluated with 41 patients grafted with CaSO4-CaPO4 and 9 patients grafted with HA-CaSO4.

RESULTS

The average age of the patient was 12.1 years with an average radiographic follow-up of 14.5 months. Average cyst size was 5.5 cm in the largest dimension and average cyst volume was 20.2 cc. 42 out of 50 (84%) showed healed cysts (Modified Neer Class 1) on the most recent radiograph or MRI. Recurrences occurred on average at 7.2 months. Activity restrictions were lifted at 3-4.5 months post-procedure. Cyst stratification by size did not show a difference in recurrence rates (p = 0.707). There was no significant difference in recurrence rate between lesions abutting the physis compared to those that were not abutting the physis (p = 0.643). There were no major complications.

CONCLUSIONS

The Sclerograft™ procedure is an image-guided approach to treating unicameral bone cysts, utilizing chemical sclerosis and regenerative bone grafting. The radiographic healing of cysts compares favorably to open curettage and grafting as determined utilizing previously published trials.