|Beitragstitel||Surgical decompression for foraminal and extraforaminal lumbar disc herniation using the far-lateral approach: patient-rated outcome depends on the involved segment|
Decompression for lumbar foraminal to extraforaminal nerve compression is commonly performed using a far-lateral transmuscular approach (FLA), and is typically associated with good patient outcomes. Results are usually reported as the average for all lumbar levels; however, clinical results may be less predictable for surgery at the lumbosacral level, due to its unique anatomic features. This study compared patient-rated outcomes after far-lateral decompression at L5/S1 compared with higher lumbar levels.
This was a retrospective study of prospectively collected data from 115 consecutive patients (73 m, 42 f; mean age 62±11 yrs) who had undergone surgery at a single level (N=89 at L1 to L5, and N=26 at L5/S1) from 1.1.2005-1.6.2014. 1482 patients from the Spine Tango database, who had undergone removal of disc herniation (non-FLA approach) served as controls. The multidimensional Core Outcome Measures Index (COMI), including scales for leg pain (LP) and back pain (LBP), was completed before surgery, and up to 2 years after surgery.
94% of the patients had completed a baseline COMI, 88% a 2-year; 83% had completed both timepoints. In the FLA group, at the 2-year follow-up, the reduction in LP was significantly (p=0.03) less for those operated at L5/S1 (2.6±2.9 points) than for those operated at L1/2 to L4/5 (4.2±3.4 points) unlike in the control group (4.5±3.2 points for L5/S1 and 4.2±3.3 points for L1/2 to L4/5). A 2-point MCIC score for LP was achieved by 77% patients in the control group, both for those operated at L5/S1 and those operated at higher lumbar levels alike. In the FLA group, the corresponding figures were 63% (L5/S1) and 81% (higher lumbar levels)(p=0.11). The reduction in COMI score showed a similar pattern to that for LP, but without statistical significance: at L5/S1, FLA 3.5±2.4 points vs control 4.6± 3.0 points reduction; at higher lumbar levels, FLA 4.8±3.0 vs control 4.8±2.9 points). There were no significant differences (p>0.05) dependent on group or lumbar level for the improvement in LBP.
Decompression of extra- and intraforaminal nerve root compression using FLA results in good patient-rated outcome at 2 years. However, the improvement in LP was inferior for the L5/S1 level compared with the other levels. This may be due to its unique anatomy. These results are important in decision-making for appropriate surgical treatment and in the management of expectations during the consent process.