Simon Heinrich Bayerl, Florian Pöhlmann, Tobias Finger, Jörg Franke, Johannes Woitzik and Peter Vajkoczy
Microsurgical decompression (MD) in patients with lumbar spinal stenosis (LSS) shows good clinical results. Nevertheless, 30%–40% of patients do not have a significant benefit after surgery—probably due to different anatomical preconditions. The sagittal profile types (SPTs 1–4) defined by Roussouly based on different spinopelvic parameters have been shown to influence spinal degeneration and surgical results. The aim of this study was to investigate the influence of the SPT on the clinical outcome in patients with LSS who were treated with MD.
The authors retrospectively investigated 100 patients with LSS who received MD. The patients were subdivided into 4 groups depending on their SPT, which was determined from preoperative lateral spinal radiographs. The authors analyzed pre- and postoperative outcome scales, including the visual analog scale (VAS), walking distance, Oswestry Disability Index, Roland-Morris Disability Questionnaire, Odom’s criteria, and the 36-Item Short Form Health Survey score.
Patients with SPT 1 showed a significantly worse clinical outcome concerning their postoperative back pain (VASback-SPT 1 = 5.4 ± 2.8; VASback-SPT 2 = 2.6 ± 1.9; VASback-SPT 3 = 2.9 ± 2.6; VASback-SPT 4 = 1.5 ± 2.5) and back pain–related disability. Only 43% were satisfied with their surgical results, compared with 70%–80% in the other groups.
A small pelvic incidence with reduced compensation mechanisms, a distinct lordosis in the lower lumbar spine with a high load on dorsal structures, and a long thoracolumbar kyphosis with a high axial load might lead to worse back pain after MD. Therefore, the indication for MD should be provided carefully, fusion can be considered, and other possible reasons for back pain should be thoroughly evaluated and treated.
Jörg Franke, Thomas Hesse, Clement Tournier, Walter Schuberth, Christian Mawrin, Jean Carles LeHuec and Henning Grasshoff
Lumbar disc herniations are associated with segmental muscle alterations of the ipsilateral segmental multifidus muscle. The aim of the present study was a histopathological analysis of the myopathological changes of the multifidus muscle and correlation with the duration of radicular symptoms.
Multifidus muscle biopsies were performed in 20 patients during discectomy. Specimens were obtained from the area of the multifidus muscle innervated by the nerve from the level of the affected disc. Histopathological findings were classified according as neurogenic tissue syndrome and nonspecific myopathological syndrome, and these results were correlated with the duration of radicular symptoms.
Results of multifidus muscle biopsies were classified as neurogenic tissue syndrome in 12 patients and as nonspecific myopathological syndrome in 8. The mean (± SD) duration of radicular symptoms was 10.75 ± 7.9 months in patients with neurogenic tissue syndrome and 4.37 ± 3.9 months in patients with a nonspecific myopathological syndrome. There was a positive correlation between group assignment and symptom duration (correlation coefficient 0.457, p = 0.043).
A long duration of radicular symptoms is associated with a neurogenic tissue syndrome, whereas a nonspecific myopathological tissue syndrome is seen in patients with shorter duration of symptoms. This suggests that patients with long duration of radicular symptoms originating from a lumbar disc herniation have an increased risk for neurogenic muscular changes, and that consideration should be given to an earlier surgical intervention.