Lower Extremity Nerve Transfers in Acute Flaccid Myelitis Patients: A Case Series

Abstract

Background: Acute flaccid myelitis (AFM) is characterized by flaccid paralysis following prodromal symptoms. Complete recovery is rare, and patients typically have residual extremity weakness. This study aimed to describe the technique and outcomes of lower extremity nerve transfers for children with AFM. Methods: A retrospective review of eight children who developed AFM in 2016 and had lower extremity nerve transfers was performed. Principles of nerve transfer were applied to develop novel nerve transfer procedures to restore function for this patient population. Pre-and postoperative muscle strength grades were reviewed, and qualitative improvements in function were recorded. Results: A variety of nerve transfers were utilized in eight patients with average time to surgery from AFM diagnosis of 15.7 months. Restoration of gluteal, femoral, hamstring, and gastrocnemius function was attempted. Variable MRC grade improvement was achieved (range MRC grade 0-4). All patients reported subjective improvements in function. Four of five patients with follow-up who underwent nerve transfers for restoration of gluteal function transitioned from wheelchair use to walking with assistive devices as their primary modes of ambulation. No donor site complications occurred. Conclusions: The unique needs of this patient population and variable patterns of residual weakness require meticulous assessment and development of individualized surgical plans. With appropriate goals and expectations in mind, functional improvement may be achieved, including return to ambulation.

Acute Flaccid Myelitis: Review of Clinical Features, Diagnosis, and Management with Nerve Transfers

“…After removal of duplicates and initial screening, 500 were reviewed and assessed for eligibility. After application of inclusion and exclusion criteria, 99 articles were included in this study (55 case reports/series, 1,4–7,9–57 33 retrospective cohort studies, 2,3,58–88 seven cross-sectional studies, 89–95 and four case-control studies 96–99 ) (Fig. 1).…”

“…19 Moore and colleagues described eight patients with proximal lower extremity weakness treated with a variety of techniques, particularly sciatic fascicle transfer to superior or inferior gluteal nerve or vastus medialis transfers, six of whom had improvement in lower extremity Medical Research Council muscle strength grade. 44 Lubelski et al reported bilateral sciatic fascicle–to-femoral transfers in four patients with persistent proximal lower extremity weakness, but did not provide postoperative outcomes. 41 Overall, 44 of the 61 patients analyzed (72.1%) had improvement in strength in at least one muscle group.…”

Hamstring branches of the sciatic nerve as donors for neurotization of the superior gluteal nerve: A cadaveric feasibility study

“…Additionally, in cases of injury from trauma or THA that could result in injury to the SGN and also to the sciatic nerve, the tibial division is rarely affected, which supports the likelihood that it will be available as a donor in cases that could ultimately benefit from nerve transfer (Simske et al, 2019; Wilson et al, 2018). Recent study by Moore et al (2021) presented that eight children who had flaccid paralysis due to acute flaccid myelitis underwent nerve transfer and all patients reported improvement Medical Research Council (MRC) grades.…”

“…Ischial tuberosity = IT and greater trochanter = greater trochanter of the femur nerve transfer (Simske et al, 2019;Wilson et al, 2018). Recent study by Moore et al (2021) presented that eight children who had flaccid paralysis due to acute flaccid myelitis underwent nerve transfer and all patients reported improvement Medical Research Council (MRC) grades.…”

Acute flaccid myelitis a review of the literature

“…Nerve transfers either end-to-end transfers or side-to-end nerve transfers are another potential option with limited data ( 47 , 48 ). One study showed patients improved from a manual muscle testing score of 0–3 ( 48 ).…”