Mismatch Between Pelvic Incidence and Lumbar Lordosis is the Key Sagittal Plane Determinant of Patient Outcome at Minimum 40 Years After Instrumented Fusion for Adolescent Idiopathic Scoliosis

Long-term follow-up of adolescent idiopathic scoliosis surgery with Harrington instrumentations: a systematic review and meta-analysis

PURPOSE

In the 1960s, Harrington instrumentation (HRI) revolutionized the surgical treatment of adolescent idiopathic scoliosis (AIS). Despite the transition to more innovative techniques, concerns regarding its impact on sagittal alignment, associations with low back pain, and correction loss have consistently persisted. The aim of this meta-analysis is precisely to evaluate the clinical and radiological outcomes, as well as the complications of patients treated with HRI over an extended follow-up period. A systematic search of articles about AIS patients who underwent HRI and reported long-term outcomes (> 10 years) was conducted on electronic databases according to PRISMA guidelines. Data regarding radiographic and clinical outcomes were extracted and meta-analyses were performed. Eleven studies comprising 644 patients were included. The mean follow-up ranged from 10.8 to 51.7 years. Radiographic analysis revealed a decrease in the main curve Cobb angle from 60.6° to 38.3°, with a correction loss of - 9.49° between postoperative and last follow-up. Concerning sagittal parameters, preoperative thoracic kyphosis was 19.65° at last follow-up, and preoperative lumbar lordosis was 42.94°. Additional spine surgeries were required in 42% of patients. Clinical outcomes varied among studies, but overall, HRI patients showed comparable quality of life and function to controls, although a higher incidence of low back pain was reported. Patients who underwent HRI exhibited suboptimal correction of rib deformity and a flattened sagittal spinal alignment. However, they generally displayed favourable long-term functional outcomes. Despite the implant's tendency to reduce lumbar curvature, patients achieved good clinical outcomes and functional scores comparable to age-matched individuals, suggesting that disability is not an inevitable consequence of lumbar flattening.

The reunion with my patients: their journey and experience 30 years after their intervention for adolescent idiopathic scoliosis via CD instrumentation

PURPOSE

Our objective was to collect the experience and current attitude of those patients, now adults, operated on for adolescent idiopathic scoliosis (AIS) more than 25 years ago with CD instrumentation (CDI).

METHODS

Prospective qualitative cross-sectional study with interpretive phenomenological analysis approach of AIS patients operated in a single center with CDI between 1985 and 1995. Patients underwent a semi-structured interview with their original surgeon. Seven agreed themes were open for conversation, and several subthemes emerged related to their experience during their journey in life. Filed notes were recorded and transcribed verbatim. We used the method of content, semantic and pragmatic analysis.

RESULTS

We contacted 103 patients, 100 agreed to participate. Mean age was 47.5 ± 3.3, mean follow-up was 30.9 ± 2.7 years. Three fundamental concerns stood out: discomfort with self-image; low back pain with daily activities; and lack of spinal flexibility. 50% were engaged in continuous physical exercise, and only some referred limitations with load-bearing work. Patients commonly described negative memories of the conservative treatment, but positive memories of the surgical process. In general, there was a good adaptation to social life (occupation, social and family relationships). Two-thirds were married, and 65 women had offspring. A frequent concern was the excess of radiographs over the years, and three developed breast cancer.

CONCLUSIONS

Factors such as dissatisfaction with self-image, low back pain, and spine stiffness were relevant to patients throughout their journeys. Despite this, the great majority were satisfied with the treatment received, which allowed them to lead an integrated life in society.

LEVEL OF EVIDENCE

Level II.

Factors affecting functional disability in patients with non-specific chronic low back pain: a cross-sectional study

Background

Knowledge about factors affecting functional disability in patients with non-specific chronic low back pain (NSCLBP) is helpful in guiding treatment, but there has been little systematic research on this topic. This study aimed to identify independent factors contributing to functional disability in NSCLBP patients especially the impact of sagittal parameters and body postures in work, learning, and daily life.

Methods

Sociodemographic data, sagittal parameters, Oswestry Disability Index (ODI), Numeric Rating Scale (NRS), and 36-item Short Form Health Survey (SF-36) of NSCLBP patients were collected. Patients were divided into a low-functional disability group (ODI ≤ 20) and a high-functional disability group (ODI > 20), and the ODI was converted to ranked ODI (RODI) accordingly. Sociodemographic data, sagittal parameters, NRS, and SF-36 were compared by univariate analysis between both groups. A correlation analysis of the aforementioned factors with the RODI was conducted. The sociodemographic data and sagittal parameters related to the RODI were analyzed by logistic regression to select potential RODI-associated factors. The level of significance was set at P < 0.05.

Results

Age, educational background, daily main posture while working or learning (DMPWL), daily standing time while working or learning (DSTTWL), daily sitting time while resting (DSITR), sacral slope-pelvic tilt (SS-PT), spinosacral angle (SSA), NRS, and SF-36 (except mental health, MH) were different between the two groups (P < 0.05). Correlation analysis showed that they were related to the RODI (P < 0.05). The logistic regression analysis indicated that the regression coefficients of a college degree, postgraduate diploma, DSITR, and SSA were (B = -0.197; P = 0.003), (B = -0.211; P = 0.006), (B = -0.139; P = 0.039), and (B = -0.207; P = 0.001), respectively, and the odds ratio (OR) and 95% confidence interval (CI) were 0.489 (0.308; 0.778), 0.299 (0.125; 0.711), 0.875 (0.772; 0.993), and 0.953 (0.925; 0.981), respectively.

Conclusion

Educational background, DSITR, and SSA are independent factors affecting functional disability in NSCLBP patients. NSCLBP patients with a lower educational background, shorter DSITR, or smaller SSA should be taken into account in clinical practice and therapeutic choices. Extending sitting time for rest and the avoidance of a forward-leaning standing position are beneficial for reducing functional disability in NSCLBP.

Clinical Improvement After Lumbar Fusion: Using PROMIS to Assess Recovery Kinetics

STUDY DESIGN

Retrospective review of a single institution cohort.

OBJECTIVE

The goal of this study is to identify features that predict delayed achievement of minimum clinically important difference (MCID) following elective lumbar spine fusion using Patient-Reported Outcomes Measurement Information System (PROMIS) surveys.

SUMMARY OF BACKGROUND DATA

Preoperative prediction of delayed recovery following lumbar spine fusion surgery is challenging. While many studies have examined factors impacting the achievement of MCID for patient-reported outcomes in similar cohorts, few studies have assessed predictors of early functional improvement.

METHODS

We retrospectively reviewed patients undergoing elective one-level posterior lumbar fusion for degenerative pathology. Patients were subdivided into two groups based on achievement of MCID for each respective PROMIS domain either before six months ("early responders") or after six months ("late responders") following surgical intervention. Multivariable logistic regression analysis was used to determine features associated with odds of achieving distribution-based MCID before or after six months follow up.

RESULTS

147 patients were included. The average age was 64.3±13.0 years. At final follow-up, 57.1% of patients attained MCID for PI and 72.8% for PF. However, 42 patients (49.4%) reached MCID for PI by six months, compared to 44 patients (41.1%) for PF. Patients with severe symptoms had the highest probability of attaining MCID for PI (OR 10.3; P =0.001) and PF (OR 10.4; P =0.001) Preoperative PROMIS symptomology did not predict early achievement of MCID for PI or PF. Patients who received concomitant iliac crest autograft during their lumbar fusion had increased odds of achieving MCID for PI (OR 8.56; P =0.001) before six months.

CONCLUSION

Our study demonstrated that the majority of patients achieved MCID following elective one-level lumbar spine fusion at long-term follow-up, although less than half achieved this clinical benchmark for each PROMIS metric by six months. We also found that preoperative impairment was not associated with when patients would achieve MCID. Further prospective investigations are warranted to characterize the trajectory of clinical improvement and identify the risk factors associated with poor outcomes more accurately.

The New Modular Sforzesco Brace (Modular Italian Brace) Is as Effective as the Classical One: A Retrospective Controlled Study from a Prospective Cohort

Background: The Sforzesco brace is a very rigid push-up brace effective in adolescent idiopathic scoliosis (AIS). We recently developed a new Sforzesco brace based on modularity (the Modular Italian brace-MI brace) that could allow standardization, facilitating global expertise diffusion, increased modifiability and adaptability, and cost savings due to longer brace life. We aimed to compare the short-term results of the two braces. Methods: The retrospective study included 231 consecutive AIS treated with a MI brace (N = 53) or Sforzesco brace (N = 178). The main outcome was the first 6-month follow-up out-of-brace radiograph Cobb angle change. Secondary outcomes included the in-brace Cobb degrees and aesthetics (TRACE), prominence (angle of trunk rotation and mm), kyphosis, and lordosis changes. Results: The two groups were similar at baseline, apart from more immature patients in MI brace. Both braces reduced the Cobb angle (-6° out-of-brace; -16° in-brace) without differences between groups. All secondary outcomes improved, apart from a statistically and clinically insignificant 3° kyphosis reduction. The MI brace participants were 4.9 times more likely to improve the Cobb angle than the Sforzesco brace (OR = 4.92; 95%CI 1.91-12.64; p = 0.001). Conclusions: These findings suggest that the MI-brace can be safely used instead of the classical Sforzesco brace. However, further studies of different designs and longer follow-ups are needed to confirm these findings.

Adolescent idiopathic scoliosis with concomitant spondylolysis: choice of fusion levels and evaluation of the outcomes obtained leaving the lytic level not instrumented

PURPOSE

7% of adolescent idiopathic scoliosis (AIS) patients also present with a pars defect. To date, there are no available data on the results of fusion ending proximal to a spondylolysis in the setting of AIS. The aim of this study was to analyze the outcomes of posterior spinal fusion (PSF) in this patient cohort, to investigate if maintaining the lytic segment unfused represents a safe option.

METHODS

Retrospective review of all patients who received PSF for AIS, presented with a spondylolysis or spondylolisthesis and had a min. 2-year follow-up. Demographic data, instrumented levels, and preoperative radiographic data were collected. Mechanical complications, coronal or sagittal parameters, amount of slippage, and pain levels were evaluated.

RESULTS

Data from 22 patients were available (age 14.4 ± 2.5 years), 18 Lenke 1-2 and 4 Lenke 3-6. 5 patients (24%) had an isthmic spondylolisthesis, all Meyerding I. The mean preoperative Cobb angle of the instrumented curves was 58 ± 13°. For 18 patients, the lowest instrumented vertebra (LIV) was the last touched vertebra (LTV); for 2, LIV was distal to the LTV; for 2, LIV was one level proximal to the LTV. The number of segments between the LIV and the lytic vertebra ranged from 1 to 6. At the last follow-up, no complications were observed. The residual curve below the instrumentation measured 8.5 ± 6.4°, the lordosis below the instrumented levels was 51.4 ± 13°. The magnitude of the isthmic spondylolisthesis remained constant for all included patients. Three patients reported minimal occasional low back pain.

CONCLUSION

The LTV can be safely used as LIV when performing PSF for the management of AIS in patients with L5 spondylolysis.

Characteristics of Sagittal Alignment in Patients with Severe and Rigid Scoliosis

OBJECTIVE

There has been increasing concern about the importance of sagittal alignment in the evaluation and treatment of spinal scoliosis. However, recent studies have only focused on patients with mild to moderate scoliosis. To date, little is known about the sagittal alignment in patients with severe and rigid scoliosis (SRS). This study was performed to evaluate the sagittal alignment in patients with SRS, and to analyze how it was altered after corrective surgery.

METHODS

In this retrospective cohort study, we included 58 patients with SRS who underwent surgery from January 2015 to April 2020. Preoperative and postoperative radiographs were reviewed, and the sagittal parameters mainly included thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacrum slope (SS), and sagittal vertical axis (SVA). The sagittal balance state was evaluated according to whether the PI minus the LL (PI-LL) was less than 9°, and the patients were divided into thoracic hyperkyphosis and normal groups based on whether the TK exceeded 40°. The Student's t test, Pearson's test, and Receiver operating characteristic (ROC) curve analysis were used to compare related parameters between the different groups.

RESULTS

The mean follow-up duration was 2.8 years. Preoperatively, the mean PI was 43.6 ± 9.4°, and the mean LL was 65.2 ± 13.9°. Sixty-nine percent of patients showed sagittal imbalance, and they showed larger TK and LL values and smaller PI and SVA values than those with sagittal balance. Additionally, most patients (44/58) presented with thoracic hyperkyphosis; this group had smaller PI and SVA values than the normal patients. Patients with syringomyelia-associated scoliosis were more likely to present with thoracic hyperkyphosis. The TK and LL values were significantly decreased, and 45% of patients with preoperative sagittal imbalance recovered after surgery. These patients had a larger PI (46.4 ± 9.0° vs 38.3 ± 8.8°, P = 0.003) and a smaller TK (25.5 ± 5.2° vs 36.3 ± 8.0°, P = 0.000) at the final follow-up.

CONCLUSION

Preoperative sagittal imbalance appears in the majority of SRS patients, accounting for approximately 69% of our cohort. Patients with small PI values or syringomyelia-associated scoliosis were more likely to present with thoracic hyperkyphosis. Sagittal imbalance can generally be corrected by surgery, except in patients with a PI less than 39°. To achieve good postoperative sagittal alignment, we recommend controlling the TK to within 31°.

Long-Term Health-Related Quality of Life After Harrington Instrumentation and Fusion for Adolescent Idiopathic Scoliosis: A Minimum 40-Year Follow-up

BACKGROUND

Despite its importance for clinical decisions, the long-term consequences of posterior spinal instrumentation and fusion (PSIF) for adolescent idiopathic scoliosis (AIS), particularly in the lower lumbar spine, remain unclear. This study evaluates the long-term health-related quality of life and the need for a further surgical procedure in patients treated with Harrington instrumentation from 1961 to 1977 according to the lowest instrumented vertebra (LIV) and in comparison with age-matched norms.

METHODS

A search was performed to identify and contact the 314 identified patients with AIS treated with PSIF by Dr. L.A. Goldstein. The assessment included identified subsequent spine surgery, the Oswestry Disability Index (ODI), Scoliosis Research Society-7 (SRS-7), EuroQol-5 Dimensions (EQ-5D), and Patient-Reported Outcomes Measurement Information System-29 (PROMIS-29). The health-related quality of life was compared with U.S. norms and, within the cohort, was compared by patient factors, LIV, and subsequent spine surgery.

RESULTS

In this study, 134 patients (42.7%) were identified; 24 (7.6%) had died, 81 (25.8%) consented to participate in the study, and 29 (9.2%) declined participation. The mean follow-up was 45.4 years (range, 40 to 56 years). There were 81 patients who completed the surveys, 77 patients who completed the SRS-7, 77 patients who completed the ODI, and 76 patients who completed the PROMIS-29 and EQ-5D. There were 12.8% of patients with LIV L3 or proximal and 36.4% with LIV L4 or distal who had an additional surgical procedure (odds ratio, 3.98). Comparing the ODI of patients who had undergone an additional surgical procedure with those who had not showed 42% and 73% minimal disability, 53% and 23% moderate disability, and 5% and 2% severe disability. Of the patients who had not undergone an additional surgical procedure, those with LIV L3 or proximal had mean scores of 14.12 points for the ODI and 23.3 points for the SRS-7 and those with LIV L4 or distal had mean scores of 17.9 points for the ODI and 22.7 points for the SRS-7; these differences were not significant. The mean PROMIS-29 and EQ-5D scores were not different from normal U.S. age-based means.

CONCLUSIONS

Patients with AIS treated with PSIF at a mean 45-year follow-up and LIV L4 or distal had a higher rate of undergoing an additional surgical procedure than those with LIV L3 or proximal. Patients undergoing an additional surgical procedure had lower health-related quality of life than those who did not. Despite this, there was no difference in health-related quality of life for patients with LIV L4 or distal compared with patients with LIV L3 or proximal. This cohort of patients with AIS treated with PSIF demonstrates normal self-reported health-related quality of life compared with the age-matched general population. These long-term outcomes of PSIF for AIS are encouraging.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.