TY - JOUR
T1 - Primary outcomes of an FDA IDE trial of Spondyloplasty vs TLIF for degenerative spondylolisthesis
AU - Sasso, Rick C.
AU - Alamin, Todd F.
AU - Castro, Javier
AU - Bae, Hyun W.
AU - Villavicencio, Alan T.
AU - Gum, Jeffrey L.
AU - Perez-Cruet, Mick J.
AU - Yoon, S. Tim
AU - Lavelle, William F.
AU - Kim, Kee D.
AU - Wang, Michael Y.
AU - Guyer, Richard D.
AU - Fielding, Louie C.
AU - Yu, Elizabeth
AU - White, Andrew P.
AU - Deutsch, Harel
AU - Ray, Wilson Z.
AU - Stauff, Michael
AU - Fischgrund, Jeffrey S.
AU - Kuo, Calvin C.
AU - Shimer, Adam L.
N1 - Publisher Copyright:
© 2024
PY - 2024/9
Y1 - 2024/9
N2 - BACKGROUND CONTEXT: Durable outcome for patients with DS usually requires decompression and fusion. Spondyloplasty is an investigational procedure utilizing a dynamic sagittal tether (DST) for segmental stabilization after decompression for DS as an alternative to fusion. PURPOSE: Evaluate propensity score (PS) adjusted outcomes comparing decompression and DST stabilization versus decompression and TLIF for symptomatic grade I DS at 2 years after surgery. STUDY DESIGN/SETTING: Concurrently enrolled multi-center IDE trial with propensity score matching of groups. PATIENT SAMPLE: All patients had Grade I DS on a lateral radiograph at one level and spinal canal stenosis at one or two levels with ODI≥35 and VAS-leg/hip≥50. Full inclusion criteria are detailed at clinicaltrials.gov (NCT03115983). OUTCOME MEASURES: Primary outcome measure was composite clinical success (CCS) where a patient had to satisfy 5 criteria at 24-months follow-up: successful index implantation; improvement of at least 15 points on the Oswestry Disability Index (ODI); no decrease in neurologic status at 24 months compared to baseline unless attributable to a concurrent medical condition or other unrelated cause; no subsequent surgical intervention (SSI) at the index or adjacent levels; and no device integrity failure (breakage, separation/disassembly or dislocation). Secondary outcomes included individual components of the CCS. METHODS: Patients were enrolled into the trial at either investigational spondyloplasty or control TLIF sites. A propensity score (PS) model was developed, achieving excellent balance between trial groups. Differences between groups were calculated using average treatment effect of the treated (ATT) weighted analyses of the PS subclasses per FDA requirements. The trial was designed as a noninferiority study, with a -12.5% noninferiority margin as tested with a 95% single sided confidence interval (CI) of the between-group difference. RESULTS: All 140 spondyloplasty and 125 TLIF subjects were selected into the PS model, the equivalent of randomization. Mean±SD preoperative age of the spondyloplasty/TLIF subjects was 65.8±7.7/64.5±8.9yrs, BMI 28.1±4.7/29.3±5.3kg/m2, ODI 52.6±11.9/51.7±13.5, 42.1%/29.6% male. CCS, individual component success, between-group differences and 95% and 97.5% single-sided CI are presented in the table below. The spondyloplasty group demonstrated a 15.9% higher overall success rate, with 95% CI +2.9% > -12.5%, demonstrating noninferiority. With a 97.5% single sided lower CI of +0.4%, superiority of the spondyloplasty group was also demonstrated for the primary CCS (p=0.022). The spondyloplasty group demonstrated higher success rates on each of the individual components, however none of these differences were significant. Reoperation rates (SSI) at index or adjacent levels at 24 months were 7.8% in the spondyloplasty group and 10.1% in the TLIF group. CONCLUSIONS: Spondyloplasty – comprising surgical decompression and segmental stabilization with a dynamic sagittal tether – demonstrated superiority over TLIF at 24 months in the treatment of symptomatic degenerative spondylolisthesis. More durable outcomes, including lower reoperation rates, is the primary motivation to add instrumented fusion to surgical decompression for DS, and in this study, the spondyloplasty group had a lower reoperation rate vs TLIF. Longer-term follow-up will demonstrated if this benefit is maintained. FDA Device/Drug Status: LimiFlex Dynamic Sagittal Tether (Investigational/Not Approved), Standard of Care TLIF instrumentation and graft materials (Approved for this indication).
AB - BACKGROUND CONTEXT: Durable outcome for patients with DS usually requires decompression and fusion. Spondyloplasty is an investigational procedure utilizing a dynamic sagittal tether (DST) for segmental stabilization after decompression for DS as an alternative to fusion. PURPOSE: Evaluate propensity score (PS) adjusted outcomes comparing decompression and DST stabilization versus decompression and TLIF for symptomatic grade I DS at 2 years after surgery. STUDY DESIGN/SETTING: Concurrently enrolled multi-center IDE trial with propensity score matching of groups. PATIENT SAMPLE: All patients had Grade I DS on a lateral radiograph at one level and spinal canal stenosis at one or two levels with ODI≥35 and VAS-leg/hip≥50. Full inclusion criteria are detailed at clinicaltrials.gov (NCT03115983). OUTCOME MEASURES: Primary outcome measure was composite clinical success (CCS) where a patient had to satisfy 5 criteria at 24-months follow-up: successful index implantation; improvement of at least 15 points on the Oswestry Disability Index (ODI); no decrease in neurologic status at 24 months compared to baseline unless attributable to a concurrent medical condition or other unrelated cause; no subsequent surgical intervention (SSI) at the index or adjacent levels; and no device integrity failure (breakage, separation/disassembly or dislocation). Secondary outcomes included individual components of the CCS. METHODS: Patients were enrolled into the trial at either investigational spondyloplasty or control TLIF sites. A propensity score (PS) model was developed, achieving excellent balance between trial groups. Differences between groups were calculated using average treatment effect of the treated (ATT) weighted analyses of the PS subclasses per FDA requirements. The trial was designed as a noninferiority study, with a -12.5% noninferiority margin as tested with a 95% single sided confidence interval (CI) of the between-group difference. RESULTS: All 140 spondyloplasty and 125 TLIF subjects were selected into the PS model, the equivalent of randomization. Mean±SD preoperative age of the spondyloplasty/TLIF subjects was 65.8±7.7/64.5±8.9yrs, BMI 28.1±4.7/29.3±5.3kg/m2, ODI 52.6±11.9/51.7±13.5, 42.1%/29.6% male. CCS, individual component success, between-group differences and 95% and 97.5% single-sided CI are presented in the table below. The spondyloplasty group demonstrated a 15.9% higher overall success rate, with 95% CI +2.9% > -12.5%, demonstrating noninferiority. With a 97.5% single sided lower CI of +0.4%, superiority of the spondyloplasty group was also demonstrated for the primary CCS (p=0.022). The spondyloplasty group demonstrated higher success rates on each of the individual components, however none of these differences were significant. Reoperation rates (SSI) at index or adjacent levels at 24 months were 7.8% in the spondyloplasty group and 10.1% in the TLIF group. CONCLUSIONS: Spondyloplasty – comprising surgical decompression and segmental stabilization with a dynamic sagittal tether – demonstrated superiority over TLIF at 24 months in the treatment of symptomatic degenerative spondylolisthesis. More durable outcomes, including lower reoperation rates, is the primary motivation to add instrumented fusion to surgical decompression for DS, and in this study, the spondyloplasty group had a lower reoperation rate vs TLIF. Longer-term follow-up will demonstrated if this benefit is maintained. FDA Device/Drug Status: LimiFlex Dynamic Sagittal Tether (Investigational/Not Approved), Standard of Care TLIF instrumentation and graft materials (Approved for this indication).
UR - http://www.scopus.com/inward/record.url?scp=85201480110&partnerID=8YFLogxK
U2 - 10.1016/j.spinee.2024.06.132
DO - 10.1016/j.spinee.2024.06.132
M3 - Conference article
AN - SCOPUS:85201480110
SN - 1529-9430
VL - 24
SP - S116-S117
JO - Spine Journal
JF - Spine Journal
IS - 9
T2 - NASS 39th Annual Meeting
Y2 - 25 September 2024 through 28 September 2024
ER -