Paraspinal Muscle Quality and Functional Outcomes Following Lumbar Fusion: A Systematic Review.
Tony Tu, Nick Kelhofer, Charlotte Cheng et al.
✦ AI-curated · Sources linked
In 30 seconds
This systematic review examined whether preoperative and postoperative paraspinal muscle quality is associated with patient-reported outcomes after lumbar interbody fusion, and whether findings differ between minimally invasive surgery (MIS) and conventional open surgery (COS). It included 20 studies of adults with CT or MRI assessment of the multifidus or erector spinae. Seven of nine COS studies reported significant muscle damage after surgery, compared with two of twelve MIS studies. Across studies, better preoperative muscle quality and smaller postoperative muscle changes were generally associated with greater functional improvement, although this relationship was not consistent.
Key findings
- Seven of nine COS studies found significant pre- to postoperative muscle damage, compared with two of twelve MIS studies.
- Four of six direct comparisons found smaller declines in cross-sectional area, increases in fatty infiltration, or both after MIS in at least one muscle or setting.
- Four of five PROM-focused studies linked higher preoperative cross-sectional area or lower fatty infiltration with better postoperative functional improvement.
- One study identified multifidus fatty infiltration of 61% or greater as a threshold for not achieving clinically meaningful ODI improvement.
Why it matters
Paraspinal muscle imaging may help characterize factors associated with functional recovery after lumbar fusion. The review suggests that muscle preservation and preoperative muscle quality are relevant, but their relationship with patient-reported improvement varies across studies and surgical approaches. Imaging biomarkers should therefore be interpreted as part of a multifactorial recovery picture rather than as complete predictors of outcome.
What to keep in mind
The review included predominantly non-randomized studies, and associations between muscle measures and functional outcomes were not consistent across studies or surgical techniques.