Degenerative Compressive Myelopathy
There is a relative equipoise with regards to surgical management of degenerative compressive myelopathy. The natural history of this disease is not completely understood and, as such, it is difficult to assess the potential benefit of surgical decompression. As such, any predictive factors that might correlate with outcome are useful.
|Karpova et al. (2013)
|Objective: To examine the role of magnetic resonance imaging (MRI) in predicting outcomes after surgery for degenerative compressive myelopathy (DCM).
Methods: Comprehensive literature search of English studies with >25 participants aged >18 yr after surgical intervention, with symptomatic DCM and detailed preoperative MRI details available.
Databases: MEDLINE, EMBASE, PubMed.
Evidence: Studies were assessed for quality using modified Cochrane guidelines (1-2=poor, 3=good, 4-5=excellent). Levels of evidence were assigned using the Sackett Scale.
|1. Quality of studies was excellent (n=6), good (n=9), and poor (n=15).
2. Levels of evidence were I (n=2), II (n=3), and IV (n=25).
3. The following surgical outcomes (SO) were evaluated: recovery rate (RR) and post-operative functional score (POFS).
4. Relationship between cord compression and SO was assessed in 14 studies: transverse area (TA, n=5), compression ratio (CR, n=5), antero-posterior (AP, n=1), and qualitative measures (QM, n=3).
5. TA was significantly associated with RR but not POFS. CR, AP, and QM were not significantly associated with RR or POFS.
6. Relationship between signal intensity and SO was assessed in 24 studies: presence, area, and intensity of change on T1/T2-weight imaged (WI).
7. Presence, area, and intensity of SI on T2WI, as well as presence of SI on both T1/T2WI were significantly associated with RR and/or POFS.
In a well-designed systematic review, Karpova et al. (2013a) assessed magnetic resonance imaging characteristics that might be predictive of outcome in individuals undergoing surgical management of degenerative compressive myelopathy. They identified a mix of excellent and good-quality evidence, including 13 prospective cohort studies, that assessed imaging findings and possible associations with clinical outcomes as judged by common scoring tools included the modified Japanese Orthopedic Association scale. Overall, they found that transverse area of the spinal cord correlated with postoperative recovery but that other radiological measures were not. In addition, the absence of spinal cord hyperintensity on magnetic resonance imaging was correlated with improved post-surgical outcome as measured by the modified Japanese Orthopedic Association scale and other scales.
There is level 2 evidence (from one studies included in a systematic review: Karpova et al. 2013) that radiological features such as spinal cord transverse area, and absence of spinal cord hyperintensity of MRI, both correlate with improved clinical outcome after decompressive surgery for degenerative compressive myelopathy.