Radicular leg pain improvement or recurrence following surgical decompression alone or with arthrodesis achieved by TLIF and BMP

2011

BACKGROUND

Patients with spinal stenosis reliably achieve improvement in leg pain following decompression of the neural elements. In cases of instability, deformity, or spondylolisthesis additional arthrodesis is required and TLIF with BMP is often used to augment the fusion. Post-op leg pain can occur with TLIF, and with TLIF+BMP.

PURPOSE

This is the first study to review the timing of leg pain resolution or recurrence in patients undergoing laminectomy with and without TLIF using interbody BMP for primary and revision surgery.

STUDY DESIGN

A retrospective review of prospective clinical and radiographic data from a spine surgery database.

PATIENT SAMPLE

413 consecutive adults age 61 years (range 19-91 years) requiring laminectomy were reviewed; 343 (TLIF group) required additional posterior instrumented fusion and TLIF. TLIF group diagnoses: degenerative-146, spondylolisthesis-117, deformity-80; 70 patients did not require fusion (Lami group). 154 were revision surgeries. Excluded patients: laminotomy/discectomy, anterior-posterior fusions.

OUTCOMES MEASURE

Visual analog pain scores (VAS), Oswestry Disability Index (ODI), radiographic imaging, and leg pain defined by anatomic distribution (buttock, thigh, or past the knee) were analyzed at pre-op, 6 wks, 3 mo, 6 mo, 1 yr, 2 yr. Pain scores were compared with the sign test. ODI differences were tested for normalcy using Anderson Darling, and compared using paired t-tests. Primary and revision groups were considered together for this analysis.

METHOD

All patients had laminectomy: Lami group- 3 levels (range 1-5), TLIF group- 2.6 levels (range 1-6). TLIF group also had posterior fusion average 4.3 levels (range 2-17), and TLIF was performed (average 1.7 levels, range 1-4) with rectangular PEEK cage filled with local autograft, the disc backfilled with local autograft around the cage. Interbody BMP on absorbable collagen sponges was placed deep within the disc prior to cage placement, anterior to the cage.

RESULTS

Follow-up averaged 55 months (24-105 months). For Lami group: VAS improved from 5.7 pre-op to 2.8 (p=0.026) at 6 weeks, increasing to 3.5 at 3 months (p=0.042), and 4.4 at 2 years (p=1.0). Oswestry (ODI) improved from 49 pre-op to 25 (p<0.001) at 6 weeks, 36 (p=0.049) at 2 years. Leg pain past the knee improved in 39/47 (83%) of laminectomy patients at 6 weeks and 44/47 (94%) at 2 yrs. For TLIF group: VAS improved from 6.2 pre-op to 3.9/3.4/3.1 at 6 months/1yr/2yrs. (p<0.001); ODI improved from 49 pre-op to 34/28/26 at 6 months/1yr/2yrs (p<0.001). Resolution of leg pain reported in 212/271(78%) TLIF patients at 6 weeks, 235/271(87%) at 2 years. Long-term leg pain relief was similarly achieved (85%) for both Lami and TLIF groups. Transient increase in buttock/thigh pain at 6 weeks was seen in patients with revision laminectomy (26%), primary TLIF (1%), revision TLIF (12%), all improving or resolving by 1 year.

CONCLUSIONS

Laminectomy with or without TLIF+BMP achieved similar relief from radicular leg pain by 6 months, though TLIF was associated with more transient leg pain at 6 weeks. Maximum improvement in VAS, ODI occurs at 6 weeks for laminectomy and 6 months for TLIF. Post op increase in buttock/thigh pain was transient. Post-op leg pain beyond 6 months is as likely after TLIF+BMP as after laminectomy.