Oral Posters: MIS
Presented by: G. Anderson - View Audio/Video Presentation (Members Only)
(1) Rothman Institute, Philadelphia, PA, United States
Purpose: Residual lower back pain and recurrent herniation remain unsolved clinical problems following microdiscectomy procedures. Amniotic membrane (AM) and umbilical cord (UC) placental tissues have been used to help improve tissue healing outcomes in numerous indications in ophthalmology, wound care, and orthopaedic reconstructive procedures. Both AM and UC have been demonstrated to possess potent anti-inflammatory and anti-scarring properties which may improve post-operative patient outcomes and function, as well as reduce recurrent back pain and re-herniation after microdiscectomy.
Methods: In the present study, eighty subjects were randomized in a 1:1 ratio to either receive AM tissue or no tissue following elective lumbar microdiscectomy surgery. During follow-up, an additional 40 patient cohort was added to receive UC tissue. Tissue grafts were applied to the annular defect at the conclusion of the procedure. Patients provided preoperative and postoperative clinical assessment data out to 24 months using the Oswestry Disability Index (ODI), Short Form-12 Health Survey (SF-12) and Visual Analogue Pain Scale (VAS) for back and leg pain. Patients with symptomatic recurrent disc herniation were recorded. In the control and AM groups, all patients have completed the follow-up period; interim results for the UC group (n=13 patients) are reported here.
Results: Mean ODI scores for subjects treated with both AM (14.49) and UC (8.43) tissue graft demonstrated statistically greater improvement at 6 weeks compared to control treated patients (21.82) (Figure 1).
At 24 months, AM treated patients demonstrated statistically lower ODI scores compared to controls (Figure 2).
Similarly, SF-12 Physical Component Scores (PCS) demonstrated statistically greater gains in both the AM (43.32) and UC (45.12) tissue groups at 6 weeks compared to controls (37.87). Similar to the ODI scores, SF-12 PCS in the AM group demonstrated statistically significant improvement at 24 months. During the entire two year follow-up period, none of the subjects in the AM group sustained a recurrent herniation at the same surgical level, while 3 occurred in the control group, with 2 requiring fusion to manage persistent pain.
Conclusion: The data demonstrates statistically superior clinical outcomes following lumbar microdiscectomy, as measured by ODI and SF-12 PCS, and a lower rate of recurrent herniation with the use of an AM tissue graft compared to traditional microdiscectomy. Further, the interim results reported here suggest that UC tissue use may help improve outcomes even further: at every time point, the mean ODI and SF-12 scores reflect an improvement compared to AM treated patients. Though these results are not yet statistically significant, the trend will be further explored when the UC patient cohort completes enrollment.
Figure 1: Interim UC Data