Long-Term Outcomes Following Lumbar Nucleus Replacement

Abstract

Background: nucleus replacement devices are designed to replace the native pain-generating lumbar nucleus while preserving the annulus fibrosus, endplates, and natural motion. the Dascor Disc arthroplasty Device seemed to perform well clinically but was discontinued in 2009. While there are no commercially available nrDs today, the potential advantages of using such devices have prompted a renewed interest in further developing the technology and assessing long-term outcomes for the Dascor device.Methods: a retrospective review of hospital records from a single institution was performed to identify all patients that underwent implantation of a Dascor device between 2006 and 2009. clinical outcome and imaging data were gathered to assess device performance of the Dascor device over an extended period of time. clinical data were assessed using a visual analog scale for back pain (vas), oswestry Disability index (oDi) scores, and analgesic medication use score (ans). Magnetic resonance images were systematically evaluated at the index and adjacent disc levels: disc height, Modic changes, Pfirrmann grade, and any implant-associated findings.Results: twenty-six patients received Dascor implants. follow-up data were available for 22 patients. the mean age at time of implantation was 34.9 years. long-term data were available for 14 patients (mean, 11.5 years) with a mean improvement in vas of 4.0 +/-2.8 (P < 0.0001), oDi 33.4 +/-18.4 (P < 0.0001), and ans 0.5 (P = 0.07) compared to baseline values, while 46% developed radiological adjacent segment degeneration on Mri and 54% did not. in total, 6 patients underwent revision surgery at the index level and 3 underwent surgery at adjacent lumbar levels.Conclusions: While any conclusions should be interpreted with caution, there was a subgroup of patients that had excellent clinical and radiological outcomes. additional studies on this device or other similar devices would add to our knowledge regarding ideal treatment of discogenic low back pain in younger patients.Clinical Relevance: treatment of discogenic low back pain.

Nucleus Disc Replacement: Design and Material Selection FEA Analysis

“…A smooth nonpermeable bag would not adhere to nearby tissues, facilitating extrusion, a critical complication of nucleus replacement devices. As a result, the devices that have reached clinical application [45] have limited use.…”