Posterior spinal fusion in patients with spinal muscular atrophy: a surgical technique to allow intrathecally inject nusinersen

BACKGROUND

Nusinersen, the recently approved medical therapy in the treatment of spinal muscular atrophy (SMA), has revolutionized the natural history of this disease. Until now, surgical treatment of scoliosis in SMA patients was an exclusion criterion for drug therapy. In fact, the bone graft positioned posteriorly during surgery, in order to obtain a solid fusion, prevented the lumbar puncture necessary for the intrathecal administration of the drug. The aim is to describe a surgical technique that allows for safe and easy intrathecal administration of nusinersen.

METHODS

We present a single-center, single-surgeon case series descriptive study. From 2019 to 2021 seven consecutive patients affected by genetically confirmed SMA suitable for treatment with nusinersen and suffered from neuromuscular scoliosis needing posterior spinal fusion surgery were included in the present study. During posterior spinal fusion surgery a L3-L4 or L2-L3 laminectomy was performed to provide safer access to intrathecal injection. The drainage scar was used as a skin landmark so as to facilitate future procedures.

RESULTS

The median of operative time was 250 min (range: 200-370 min). The median correction rate was 57% (range: 43.5-68). The median of intraoperative blood loss was 650 mL (range 320-940 mL). The median value of the correction loss at the last follow-up was 10% (range: 4.5-15%).

CONCLUSIONS

The surgical procedure allowed all patients to receive nusinersen therapy without complications. The procedure described is simple and effective in providing safe intrathecal access to make these patients suitable for undertaking or continuing the protocol of treatment with nusinersen.

Arthrodesis versus dynamic neutralization: A short/mid- and long-term retrospective evaluation in degenerative disk disease treatment

Study Design

This was a retrospective comparative study.

Objectives

The aim of this study was to perform a clinical and radiological retrospective evaluation of the most used techniques for the lumbar degenerative disk disease (DDD) treatment: arthrodesis versus dynamic neutralization (DN)-Dynesys dynamic stabilization system.

Methods

The study included 58 consecutive patients affected by lumbar DDD, 28 treated with rigid stabilization and 30 with DN at our department between 2003 and 2013. The clinical evaluation was performed through the Visual Analog Scale (VAS) and the Oswestry Disability Index (ODI). The radiographic evaluation was performed through standard and dynamic X-ray projections and magnetic resonance imaging.

Results

Both techniques determined a clinical improvement in the postoperative period compared to the preoperative one. There were no significant differences between the postoperative VAS of the two techniques. The DN group postoperative ODI percentage showed a significant improvement (P = 0.026) compared to the arthrodesis group. During the follow-up, no clinically significant differences were highlighted between the two techniques. At a long term follow up period, radiographic results showed, in both groups, a L3-L4 disk mean height reduction and an increase of segmental and lumbar lordosis without significant differences between the two techniques. During an average of 96-month follow-up period, 5 (18%) patients developed an adjacent segment disease in the arthrodesis group and 6 (20%) patients developed this syndrome in the DN group.

Conclusions

We are confident in recommending arthrodesis and DN as effective techniques for lumbar DDD treatment. Both techniques are potentially burdened, with similar frequency, by the development of long-term adjacent segment disease.

Surgical approach to single-level symptomatic thoracic disc herniations through costotransversectomy: A report of ten case series

Study Design

This was an observational study.

Objectives

The treatment of symptomatic thoracic disc herniation (TDH) remains a matter of debate. We report our experience with ten patients affected by symptomatic TDH, surgically treated through costotransversectomy.

Methods

A total of ten patients (four men and six women) with single-level symptomatic TDH were surgically treated by two senior spine surgeons at our institution between 2009 and 2021. The most common type was a soft hernia. TDHs were classified as lateral (5) or paracentral (5). Preoperative clinical symptoms were varied. The diagnosis was confirmed by computed tomography (CT) and magnetic resonance imaging of the thoracic spine. The mean follow-up period was 38 months (range: 12-67 months). The Oswestry Disability Index (ODI), the Frankel grading system, and the modified Japanese Orthopedic Association (mJOA) scoring system were used as outcome scores.

Results

Postoperative CT study documented satisfactory decompression either on the nerve root or the spinal cord. All patients experienced a reduction of disability with an improved mean ODI score by 60%. Six patients reported total recovery of neurological function (Frankel Grade E) and four patients improved by 1 Grade (40%). The overall recovery rate estimated with the mJOA score was 43.5%. We reported the absence of significant difference in outcome compared to either calcified and noncalcified discs or paramedian and lateral location. Four patients had minor complications. No revision surgery was required.

Conclusion

Costotransversectomy represents a valuable tool for spine surgeons. The major limit of this technique is the possibility to approach the anterior spinal cord.

Is posterior fixation alone effective to prevent the late kyphosis after T-L fracture?

INTRODUCTION

The posterior transpedicular fixation technique is a standard procedure for stabilizing the injured thoracolumbar spine but the long-term results of this approach are controversial. Clear guidelines are missing and the literature shows complete disagreement regarding indications, approaches, surgical techniques, and type of fixation.

MATERIAL AND METHOD

The objective of this study is to investigate if the surgical treatment by posterior approach alone is always enough to prevent the late kyphotic deformity through the retrospective analysis of 219 patients affected with a thoracolumbar injury. Follow-up examinations included radiographic measurements of the sagittal index (SI) and the sagittal plane kyphosis (SPK).

RESULT

Results show that, at the follow-up, the SI remains almost stable after the surgical correction, while the SPK (which describes the eventual injury of the affected intervertebral disc) decreases indicating a progressive regional kyphotic deformity. Thus, in some cases posterior fixation alone is not sufficient for long-term spinal stabilization and often can be not effective to prevent the late kyphotic deformity.