Predictors for Deformity Progression in a Spinal Muscular Atrophy Cohort After Scoliosis Correction Surgery

Difficulty of administration of nusinersen in complex-column spinal muscular atrophy: New alternative technique by means of cervical intrathecal access through an Ommaya reservoir

BACKGROUND

The study aimed to describe a new Ommaya reservoir implantation method in late-onset SMA patients, assessing its safety and effectiveness under standard clinical conditions.

METHODS

Prospective observational study. Lumbar intrathecal access was unfeasible due to significant scoliosis and prior spinal surgeries with instrumentation. Patients were infused with Nusinersen through the Ommaya reservoir at Hospital Universitario La Paz (Spain) following the standard dosing protocol.

RESULTS

The cohort was composed of 6 patients, 5 individuals with type 2 SMA (83.3 %), and 1 patient presenting with type 3 SMA. 4 of the patients were functionally sitters (66.7 %) and 2 had lost this ability prior to initiating treatment (non-sitters). Mean treatment was 34.7 months. Patient discharge was done in all the cases within 48 h post-admission; no significant postoperative complications or during administration of nusinersen were reported. Functional progress was observed in all patients. Hammersmith Functional Motor Scale Expanded (HFMSE) showed a low average increase (1.0), attributed to the severity of baseline functional impairments. Improvements in upper extremity motor function, measured by the Revised Upper Limb Module (RULM), were more pronounced, with an average improvement of 3.3. Disability levels as measured by the Egen Klassifikation 2 (EK2) scale, declined by 4.4.

CONCLUSION

the current study broadens knowledge regarding the efficacy and safety of using an Ommaya reservoir to administer nusinersen in patients with SMA Types 2 and 3. The technique demonstrated rapid, straightforward drug delivery through a subcutaneous needle, maintaining optimal sterility without radiation or the need for a multidisciplinary team.

Influence of Paraspinal Growth-Friendly Spinal Implants in Children with Spinal Muscular Atrophy on Parasol Deformity, Rib-Vertebral Angles, Thoracic, and Lung Volumes

INTRODUCTION

Children with spinal muscular atrophy (SMA) and progressive neuromuscular scoliosis often require early growth-friendly spinal implant (GFSI) treatment for deformity correction with implant fixation either through pedicle screws or bilateral to the spine using ribto pelvis fixation. It has been proposed that the latter fixation may change the collapsing parasol deformity via changes in the rib-vertebral angle (RVA) with a positive effect on thoracic and lung volume. The purpose of this study was to analyze the effect of paraspinal GFSI with bilateral rib-to-pelvis fixation on the parasol deformity, RVA, thoracic, and lung volumes.

METHODS

SMA children with (n = 19) and without (n = 18) GFSI treatment were included. Last follow-up was before definite spinal fusion at puberty. Scoliosis and kyphosis angles, parasol deformity, and index, as well as convex and concave RVA, were measured on radiographs, whereas computed tomography images were used to reconstruct thoracic and lung volumes.

RESULTS

In all SMA children (n = 37; with or without GFSI), convex RVA was smaller than concave values at all times. GFSI did not crucially influence the RVA over the 4.6-year follow-up period. Comparing age- and disease-matched adolescents with and without prior GFSI, no effect of GFSI treatment could be detected on either RVA, thoracic, or lung volumes. Parasol deformity progressed over time despite GFSI.

CONCLUSION

Despite different expectations, implantation of GFSI with bilateral rib-to-pelvis fixation did not positively influence parasol deformity, RVA and/or thoracic, and lung volumes in SMA children with spinal deformity directly and over time.

Scoliosis Orthopedic Surgery Combined With Nusinersen Intrathecal Injection Significantly Improved the Outcome of Spinal Muscular Atrophy Patient: A Case Report

Background

Spinal muscular atrophy (SMA) is an autosomal recessive disorder caused by pathogenic variation of the survival motor neuron (SMN) 1 gene. Symptoms of SMA include progressive limb muscle weakness, atrophy, and severe scoliosis. Nusinersen is an antisense oligonucleotide that can enhance the production of the SMN protein. Here, we report a case with scoliosis who received orthopedic surgery combined with Nusinersen intrathecal injections.

Case Presentation

Scoliosis orthopedic surgery followed by Nusinersen intrathecal injections was given to a 16-year-old girl who had thoracic and lumbar scoliosis and type 3 SMA. Surgery was performed for T3-S2 posterolateral fusion (PLF), with a channel left on the vertebral laminae of L3-L4. The balance of the spine and pelvis was significantly improved and the height increased by 9 cm. Lumbar puncture was conducted with local anesthesia under ultrasound and CT guidance through the laminae channel and Nusinersen was successfully injected. Comparing the two approaches, real-time ultrasound guidance for intrathecal Nusinersen injections after spinal surgery is preferred, however, CT guidance is an alternative if the initial puncture procedure is difficult. After the aforementioned multidisciplinary treatment, a good outcome was achieved, as demonstrated by a 2-point increase in RULM and MFM32 scores 2 months later.

Conclusion

Scoliosis orthopedic surgery combined with Nusinersen intrathecal injection is an effective treatment for SMA patients with scoliosis.

Anaesthetic considerations in posterior instrumentation of scoliosis due to spinal muscular atrophy: Case series of 56 operated patients

BACKGROUND

Spinal muscular atrophy (SMA) is a rare illness that often leads to severe kyphoscoliosis. This case series adds to the heretofore sparse information as regards the anaesthetic management of SMA scoliosis patients.

METHODS

This retrospective study reviewed the charts of 79 SMA patients (type II n = 34 and type III n = 45) presenting for possible scoliosis surgery during the time period 2007-2019. Special attention focused on preoperative assessment and clearance requirements, anaesthesia protocol and postoperative handling.

RESULTS

Out of 79 patients, 17 did not receive clearance for the procedure mostly due to grave respiratory insufficiency. Out of 62 patients with clearance for both surgery and anaesthesia, 56 patients [44 females, 12 males; age mean ± SD (range) 22 ± 7.3 (10-40) years] underwent the procedure. Their forced vital capacity and forced expiratory volume in 1 s were mean ± SD (range) 1.41 ± 0.53 (0.61-2.65) L and 1.26 ± 0.47 (0.52-2.27) L, respectively. Intubation difficulties and their resolution, e.g. with the help of fibreoptic technique and video laryngoscopy, are described. All 56 patients were extubated in the operating room postoperativley. Patients stayed at the postanaesthesia care unit for one (n = 48) or two (n = 8) nights. A considerable amount of the patients (19/56) developed hypokalaemia postoperatively.

CONCLUSION

This analysis is one of the bigger series of its kind and adds insight into the preoperative clearance process, the anaesthetic protocol and some of the postoperative complications, e.g. the tendency for developing postoperative hypokalaemia which has not been reported previously.