Using percutaneous parapedicle screw vertebroplasty to treat transpedicle screw loosening

An Extended Follow-up of Spinal Instrumentation Rescue with Cement Augmentation

BACKGROUND AND PURPOSE

Percutaneous cement augmentation has been reported as an effective salvage procedure for frail patients with spinal instrumentation failure, such as screw loosening, hardware breakage, cage subsidence, and fractures within or adjacent to stabilized segments. Favorable results were reported during a median follow-up period of 16 months in a retrospective analysis of 31 consecutive procedures performed in 29 patients. In the present study, the long-term effectiveness of this treatment in avoiding or postponing revision surgery is reported.

MATERIALS AND METHODS

Clinical and radiologic data of our original cohort of patients were retrospectively collected and reviewed to provide an extended follow-up assessment. The need for revision spinal surgery was assessed as the primary outcome, and the radiologic stability of the augmented spinal implants was considered as the secondary outcome.

RESULTS

An extended radiologic follow-up was available in 27/29 patients with an average of 50.9 months. Overall, 18 of 27 (66.7%) patients, originally candidates for revision surgery, avoided a surgical intervention after a cement augmentation rescue procedure. In the remaining patients, the average interval between the rescue cement augmentation and the revision surgery was 22.5 months. Implant mobilization occurred in 2/27 (7.4%) patients; rod breakage, in 1/27 (3.7%); a new fracture within or adjacent to the instrumented segment occurred in 4/27 (14.8%) patients; and screw loosening at rescued levels occurred in 5/27 (18.5%) patients.

CONCLUSIONS

In this cohort, cement augmentation rescue procedures were found to be effective in avoiding or postponing revision surgery during long-term follow-up.

When spinal instrumentation revision is not an option: Salvage vertebral augmentation with polymethylmethacrylate for mechanical complications: A systematic review

Intoduction

Mechanical complications from spinal fusion including implant loosening or junctional failure result in poor outcomes, particularly in osteoporotic patients. While the use of percutaneous vertebral augmentation with polymethylmethacrylate (PMMA) has been studied for augmentation of junctional levels to offset against kyphosis and failure, its deployment around existing loose screws or in failing surrounding bone as a salvage percutaneous procedure has been described in small case series and merits review.

Research Question

How effective and safe is the use of PMMA as a salvage procedure for mechanical complications in failed spinal fusion?.

Materials and Methods

Systematic search of online databases for clinical studies using this technique.

Results

11 studies were identified, only consisting of two case reports and nine case series. Consistent improvements were observed in pre- to post-operative VAS and with sustained improvements at final follow-up. The extra- or para-pedicular approach was the most frequent access trajectory. Most studies cited difficulties with visibility on fluoroscopy, using navigation or oblique views as a solution for this.

Discussion and Conclusions

Percutaneous cementation at a failing screw-bone interface stabilises further micromotion with reductions in back pain. This rarely used technique is manifested by a low but increasing number of reported cases. The technique warrants further evaluation and is best performed within a multidisciplinary setting at a specialist centre. Notwithstanding that underlying pathology may not be addressed, awareness of this technique may allow an effective and safe salvage solution with minimal morbidity for older sicker patients.

Transforaminal Vertebroplasty for Screwed Vertebrae: A New Minimally Invasive Technique

OBJECTIVE

Pedicle screw loosening and fractures of instrumented vertebrae are not uncommon and require reoperations, which are an immense burden on the patient and health care system. We aimed to describe a novel, simple percutaneous technique on instrumented vertebrae for treating pedicle screw loosening and demonstrate that corpus with osteoporotic vertebral compression fractures can be managed with this simple technique.

METHODS

This retrospective study was performed using data gathered from 15 patients who underwent transforaminal vertebroplasty due to symptomatic pedicle screw loosening and vertebral body fracture between 2020 and 2021. Patients' symptoms, radiologic findings, intraoperative findings, and clinical outcomes were noted.

RESULTS

This series consisted of 5 male and 10 female patients, and the mean duration of follow-up was 8 months (range: 3 to 13). The average age was 66.67 ± 4.59 years (range: 55-72). Preoperatively, symptoms were leg pain, numbness of the lower extremity, and back pain. Postoperatively, no major complications were observed. Clinical progression of pedicle screw loosening and osteoporotic vertebral compression fractures were halted in all patients. None of the patients had permanent neurologic deficits. All the patients reported a dramatic decrease in pain immediately after the procedure. The vertebral fracture was detected in 3 patients, and screw loosening occurred in 12 patients. All symptoms resolved during follow-up.

CONCLUSIONS

Our preliminary results imply that transforaminal vertebroplasty is a safe and easy percutaneous technique in symptomatic pedicle screw loosening and osteoporotic vertebral compression fractures in the instrumented vertebrae. Further trials on larger series are necessary to validate our data.