David Christopher Kieser, Derek Thomas Cawley, Takashi Fujishiro, Simon Mazas, Louis Boissière, Ibrahim Obeid, Vincent Pointillart, Jean-Marc Vital and Olivier Gille
The objective of this study was to identify the risk factors of anterior bone loss (ABL) in cervical disc arthroplasty (CDA) and the subsequent effect of this phenomenon.
The authors performed a retrospective radiological review of 185 patients with a minimum 5-year follow-up after CDA (using Bryan, Discocerv, Mobi-C, or Baguera C). Postoperative radiographs were examined and compared to the initial postoperative films to determine the percentage of ABL. The relationship of ABL to potential risk factors was analyzed.
Complete radiological assessment was available in 145 patients with 193 CDRs and 383 endplates (average age 45 years, range 25–65 years, 54% women). ABL was identified in 63.7% of CDRs (48.7% mild, 11.9% moderate, 3.1% severe). Age (p = 0.770), sex (p = 0.200), postoperative alignment (p = 0.330), midflexion point (p = 0.509), maximal flexion (p = 0.080), and extension (p = 0.717) did not relate to ABL. There was no significant difference in the rate of severe ABL between implants. Multilevel surgery conferred an increased risk of any and severe ABL (p = 0.013 for both). The upper endplate, defined as superior to the CDA, was more commonly involved (p = 0.008), but there was no significant difference whether the endplate was between or not between implants (p = 0.226). The development of ABL did not affect the long-term range of movement (ROM) of the CDA, but did increase the overall risk of autofusion. ABL was not associated with pain or functional deficits. No patients required a reoperation or revision of their implant during the course of this study, and there were no cases of progressive ABL beyond the first year.
ABL is common in all implant types assessed, although most is mild. Age, sex, postoperative alignment, ROM, and midflexion point do not relate to this phenomenon. However, the greater the number of levels operated, the higher the risk of developing ABL. The development of ABL has no long-term effect on the mechanical functioning of the disc or necessity for revision surgery, although it may increase the rate of autofusion.
Caglar Yilgor, Nuray Sogunmez, Yasemin Yavuz, Kadir Abul, Louis Boissiére, Sleiman Haddad, Ibrahim Obeid, Frank Kleinstück, Francisco Javier Sánchez Pérez-Grueso, Emre Acaroğlu, Anne F. Mannion, Ferran Pellise, Ahmet Alanay and the European Spine Study Group
The subtraction of lumbar lordosis (LL) from the pelvic incidence (PI) offers an estimate of the LL required for a given PI value. Relative LL (RLL) and the lordosis distribution index (LDI) are PI-based individualized measures. RLL quantifies the magnitude of lordosis relative to the ideal lordosis as defined by the magnitude of PI. LDI defines the magnitude of lower arc lordosis in proportion to total lordosis. The aim of this study was to compare RLL and PI − LL for their ability to predict postoperative complications and their correlations with health-related quality of life (HRQOL) scores.
Inclusion criteria were ≥ 4 levels of fusion and ≥ 2 years of follow-up. Mechanical complications were proximal junctional kyphosis/proximal junctional failure, distal junctional kyphosis/distal junctional failure, rod breakage, and implant-related complications. Correlations between PI − LL, RLL, PI, and HRQOL were analyzed using the Pearson correlation coefficient. Mechanical complication rates in PI − LL, RLL, LDI, RLL, and LDI interpreted together, and RLL subgroups for each PI − LL category were compared using chi-square tests and the exact test. Predictive models for mechanical complications with RLL and PI − LL were analyzed using binomial logistic regressions.
Two hundred twenty-two patients (168 women, 54 men) were included. The mean age was 52.2 ± 19.3 years (range 18–84 years). The mean follow-up was 28.8 ± 8.2 months (range 24–62 months). There was a significant correlation between PI − LL and PI (r = 0.441, p < 0.001), threatening the use of PI − LL to quantify spinopelvic mismatch for different PI values. RLL was not correlated with PI (r = −0.093, p > 0.05); therefore, it was able to quantify divergence from ideal lordosis for all PI values. Compared with PI − LL, RLL had stronger correlations with HRQOL scores (p < 0.05). Discrimination performance was better for the model with RLL than for PI − LL. The agreement between RLL and PI − LL was high (κ = 0.943, p < 0.001), moderate (κ = 0.455, p < 0.001), and poor (κ = −0.154, p = 0.343), respectively, for large, average, and small PI sizes. When analyzed by RLL, each PI − LL category was further divided into distinct groups of patients who had different mechanical complication rates (p < 0.001).
Using the formula of PI − LL may be insufficient to quantify normolordosis for the whole spectrum of PI values when applied as an absolute numeric value in conjunction with previously reported population-based average thresholds of 10° and 20°. Schwab PI − LL groups were found to constitute an inhomogeneous group of patients. RLL offers an individualized quantification of LL for all PI sizes. Compared with PI − LL, RLL showed a greater association with both mechanical complications and HRQOL. The use of RLL and LDI together, instead of PI − LL, for surgical planning may result in lower mechanical complication rates and better long-term HRQOL.
Kazunori Hayashi, Louis Boissière, Fernando Guevara-Villazón, Daniel Larrieu, Susana Núñez-Pereira, Anouar Bourghli, Olivier Gille, Jean-Marc Vital, Ferran Pellisé, Francisco Javier Sánchez Pérez-Grueso, Frank Kleinstück, Emre Acaroğlu, Ahmet Alanay and Ibrahim Obeid
Achieving high patient satisfaction with management is often one of the goals after adult spinal deformity (ASD) surgery. However, literature on associated factors and their correlations with patient satisfaction is limited. The aim of this study was to determine the clinical and radiographic factors independently correlated with patient satisfaction in terms of management at 2 years after surgery.
A multicenter prospective database of ASD surgery was retrospectively reviewed. The demographics, complications, health-related quality of life (HRQOL) subdomains, and radiographic parameters were examined to determine their correlation coefficients with the Scoliosis Research Society-22 questionnaire (SRS-22R) satisfaction scores at 2 years (Sat-2y score). Subsequently, factors determined to be independently associated with low satisfaction (Sat-2y score ≤ 4.0) were used to construct 2 types of multivariate models: one with 2-year data and the other with improvement (score at 2 years − score at baseline) data.
A total of 422 patients who underwent ASD surgery (mean age 53.1 years) were enrolled. All HRQOL subdomains and several coronal and sagittal radiographic parameters had significantly improved 2 years after surgery. The Sat-2y score was strongly correlated with the SRS-22R self-image (SI)/appearance subdomain (r = 0.64), followed by moderate correlation with subdomains related to standing (r = 0.53), body pain (r = 0.49–0.55), and function (r = 0.41–0.55) at 2 years. Conversely, the correlation between radiographic or demographic parameters with Sat-2y score was weak (r < 0.4). Multivariate analysis to eliminate confounding factors revealed that a worse Oswestry Disability Index (ODI) score for standing (≥ 2 points; OR 4.48) and pain intensity (≥ 2 points; OR 2.07), SRS-22R SI/appearance subdomain (< 3 points; OR 2.70) at 2 years, and a greater sagittal vertical axis (SVA) (> 5 cm; OR 2.68) at 2 years were independent related factors for low satisfaction. According to the other model, a lower improvement in ODI for standing (< 30%; OR 2.68), SRS-22R pain (< 50%; OR 3.25) and SI/appearance (< 50%; OR 2.18) subdomains, and an inadequate restoration of the SVA from baseline (< 2 cm; OR 3.16) were associated with low satisfaction.
Self-image, pain, standing difficulty, and sagittal alignment restoration may be useful goals in improving patient satisfaction with management at 2 years after ASD surgery. Surgeons and other medical providers have to take care of these factors to prevent low satisfaction.