A Novel Classification of Sagittal Spinal Alignment to Aid Surgical Planning for Adult Spinal Deformity

N/ANot Yet RecruitingNCT06470152

Xuanwu Hospital, Beijing200 enrolled

Overview

Surgical outcomes, including radiographic outcomes, patient-reported outcomes, postoperative complications, and revision surgery rates, were compared in patients with adult spinal deformity who underwent correction surgery with reference to our pelvic incidence-dependent (PI-dependent) clustering of sagittal spinal alignment and existing standards (sagittal age-adjusted score \[SAAS\], global alignment and proportion \[GAP\] score, and Roussouly classification). Our findings may provide tangible guidance for surgical decision-making in ASD.

Study Type

INTERVENTIONAL

Allocation

NON_RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Enrollment

200

Conditions

Adult Spinal Deformity Sagittal Deformity Sagittal Alignment Sagittal Imbalance

Correction strategy in reference to our PI-dependent clustering of sagittal alignmentPROCEDURE

For type I patients (PI \< 39.56°), the target LL = -0.13\*PI2+9.36\*PI-134.08; for type II patients (39.56° ≤ PI \< 49.16°), the target LL = 0.45\*PI+26.57; for type III patients (49.16° ≤ PI \< 58.31°), the target LL = -0.15\*PI2+17.09\*PI-420.57; for type IV patients (PI \> 58.31°), the target LL = 0.06\*PI2-7.55\*PI+289.77. Prediction intervals of 95% confidence is adopted as the target LL range.

Correction strategy in reference to the SAAS scorePROCEDURE

This new score is composed of three sagittal parameters (PI-LL, PT and TPA). For these three parameters, points were assigned based on offset with age-adjusted targets 0 points if the parameter was within 10 years of the patient's age (Match). For each 20 years above the age-adjusted target, 1 point was added (e.g., + 1 point between + 10 and + 30, + 2 points between +30 and +50). Conversely, 1 point was subtracted for each 20 years below the age-adjusted target (e.g., -1 point between -10 and -30, -2 points between -30 and -50). SAAS was calculated by adding all 3 components, creating a discreet score that could have a negative value (under corrected) or positive value (over corrected). SAAS was sub-categorized into "SAAS-Under" if it was less than -1, "SAAS-Match" if it was between -1 and + 1 or "SAAS-Over" if it was greater than + 1.

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1. ≥ 18 years of age at the time of treatment; 2. Complete radiographic data, including standing posteroanterior and lateral whole-spine radiographs, lumbar computed tomography, and lumbar magnetic resonance imaging; 3. Radiographic evidence of ASD: sagittal vertical axis ≥ 50 mm, pelvic tilt ≥ 25°, pelvic incidence-lumbar lordosis mismatch ≥ 10°, and/or thoracic kyphosis ≥ 60°. Exclusion Criteria: 1. Any type of previous spinal surgery; 2. Other musculoskeletal problems impeding walking ability, syndromic or neuromuscular diseases such as Parkinson\'s disease, inflammatory conditions such as ankylosing spondylitis, infectious conditions such as spinal tuberculosis, metabolic diseases such as severe osteoporosis, and/or serious general medical conditions such as sepsis or malignancy; 3. Pathology of deformity as follows: post-traumatic deformity, adult idiopathic scoliosis of the thoracic spine, or de-novo lumbar scoliosis; 4. Hip joint Kellgren-Lawrence grade ≥ II, history of hip joint and/or knee joint pain, and/or previous joint replacement.

Outcomes

Primary Outcomes

Proximal Junctional Kyphosis

Proximal junctional kyphosis (PJK) was defined by a proximal junctional angle (PJA) (Cobb angle between the superior endplate of UIV+2 and inferior endplate of UIV) of \> 10° and a PJA angle difference of \> 10° from baseline at any time point up to latest follow-up.

Time frame: Two years after surgery

Secondary Outcomes

Scoliosis Research Society-22

The 22-item SRS-22r questionnaire is specific to scoliosis-related patient-reported outcomes, and consists of 6 domains: function, pain, self-image, mental health, satisfaction, and subtotal, with each domain being scored from 1 to 5 where higher scores correspond to better patient outcomes.

Time frame: One month, 3 months, 6 months, 1 year, and 2 years after surgery

Oswestry disability index

The validated ODI is a self-administered questionnaire for evaluating back-specific functional disability, consisting of 10 items with scores from 0 to 5, and higher ODI indicates more severe disability.

Time frame: One month, 3 months, 6 months, 1 year, and 2 years after surgery

Achievement of minimal clinically important difference

A prespecified MCID of 10 points was used for the ODI. The minimum clinically important difference (MCID) values for the SRS-22r based on data from a Japanese cohort have previously been reported as follows: function = 0.90, pain = 0.85, self-image = 1.05, mental health = 0.70, and subtotal = 1.05.