Compressive Postoperative Seromas Causing Delayed Neurological Deterioration Following Cervical Laminectomy and Instrumented Fusion

Abstract

Compressive postoperative seromas in the cervical spine are a rare but significant complication following cervical laminectomy and instrumented fusion. There is a paucity of cases reported in the literature, with a majority of the reported cases attributing seroma formation to the use of recombinant human bone morphogenetic protein-2 (rhBMP-2). In this article, we report four cases of compressive postoperative seroma in the absence of rhBMP-2 use and highlight similarities in their clinical presentations. We postulate that seroma formation is a significant complication of the dead space that results following posterior instrumentation in the cervical spine, with or without the use of rhBMP-2. The typical presentation is one of the gradual delayed neurological deterioration several days following the index surgery and after drain removal. Neurological deterioration can be reversed rapidly with early recognition and drainage of the seroma.

Keywords: bmp-2; degenerative cervical myelopathy; neurological complication; post-operative seroma; posterior cervical decompression and fusion.

Figure 1. Preoperative sagittal (A) and axial (B) MRI showing multilevel cervical cord compression, C4-C5 myelomalacia, and mild kyphosis

Figure 2. Sagittal (A) and axial (B) MRI on postoperative day eight demonstrating a large fluid collection (yellow arrows) compressing the spinal cord (red arrows)

Figure 3. Postoperative sagittal (A) and axial (B) MRI demonstrating the re-expansion of the cervical thecal sac (yellow arrows) after drainage of the seroma

Figure 4. (A) Preoperative CT showing segmental OPLL (yellow arrows). (B) Preoperative MRI showing multilevel cord compression. (C) MRI on postoperative day six demonstrating compressive seroma (red arrow).

OPLL: Ossification of the posterior longitudinal ligament.

Figure 5. (A) Preoperative MRI demonstrating multilevel cord compression with mild kyphosis. (B) Immediate postoperative MRI demonstrating adequate posterior decompression (yellow arrow) and improved alignment. (C) MRI on postoperative day 11 showing a large compressive seroma (red arrow).

Figure 6. (A) Preoperative MRI demonstrating multilevel cord compression and mild kyphosis. (B) MRI on postoperative day seven demonstrating compressive seroma (yellow arrow). (C) Immediate post-aspiration MRI demonstrating re-expansion of thecal sac (red arrow) following seroma drainage. (D) MRI on post-aspiration day 10 showing a slight increase in the size of the seroma (blue arrows) without significant mass effect on the spinal cord.