Idiopathic scoliosis refers to spinal curvature with no known cause, occurring during a child’s growth period. Beyond causing trunk deformities, collapse, and chronic pain, it significantly reduces labor capacity, restricts normal daily activities, and seriously impacts psychological well-being. In severe cases, it leads to lifelong disability, impaired quality of life, and social issues—for example, 76% of female patients remain unmarried. Early-onset or severe scoliosis can result in underdeveloped lungs, atelectasis, cardiopulmonary dysfunction, or even paraplegia, thus reducing life expectancy.
PUMC Classification
Peking Union Medical College (PUMC) classifies idiopathic scoliosis into 3 major types and 13 subtypes, each guiding a specific treatment strategy based on deformity complexity:
PUMC Type I – One apical vertebra
PUMC Type II – Two apical vertebrae
PUMC Type III – Three apical vertebrae
PUMC Type I – One apical vertebra
Ia – Thoracic curve Ib – Thoracolumbar curve Ic – Lumbar curve
Fusion Range and Surgical Approach
Ia – Posterior fusion, or thoracoscopic anterior approach
Ib – Anterior approach preferred
Ic – Anterior approach preferred
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PUMC Type II – Two apical vertebrae
IIa Double thoracic curve IIb Thoracic curve greater than lumbar curve
IIc Thoracic curve ≈ Lumbar curve IId Thoracic curve < Lumbar curve
Fusion Range and Surgical Approach
IIa (Double thoracic curve)
1, Fusion of both the upper thoracic and main thoracic curves is required if:
• Upper thoracic curve > 30°
• Bending film shows > 20°
• Shoulders are level or the left shoulder is higher
2, Otherwise, posterior fusion of the main thoracic curve alone may be sufficient.
IIb Thoracic curve greater than lumbar curve
| TL kyphosis (basic requirements) | Lumbar curve | Lumbar curve flexibility | Lumbar curve AVR | Fusion range and surgical approach |
| IIb1 | ＜10° | ≤45° | ≥70% | ＜II° | Posterior thoracic curve |
| IIb1 | ≥10° | ＞45° | ＜70% | ≥II° | Posterior thoracic + lumbar curves |
IIc Thoracic curve ≈ Lumbar curve
| Subtype | Flexibility | Fusion range and surgical approach |
| IIc1 | Thoracic curve > Lumbar curve / Thoracolumbar curve Thoracic curve bending < 25° | Anterior approachlumbar curve / thoracolumbar curve |
| IIc2 | Thoracic curve > Lumbar curve / Thoracolumbar curve Thoracic curve bending > 25° | Posterior approachthoracic curve + lumbar/thoracolumbar curve |
| IIc3 | Thoracic curve < lumbar curve / thoracolumbar curve | Refer to IIb |
IId Thoracic curve < Lumbar curve
| Subtype | Thoracic curve bending | Fusion range and surgical approach |
| IId1 | ≤25° | Anterior approachlumbar curve / thoracolumbar curve |
| IId2 | > 25° | Posterior approachthoracic curve + lumbar/thoracolumbar curve |
PUMC Type III – Three apical vertebrae
IIIa Distal curve meets the criteria of IIb1. IIIb Distal curve meets the criteria of IIb2.
Fusion Range and Surgical Approach
IIIa: Posterior selective fusion of the proximal double thoracic curves, or fusion of the main thoracic curve only.
IIIb: Posterior fusion of all three curves, or fusion of the main thoracic and lumbar/thoracolumbar curves.
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Treatment Solutions for Idiopathic Scoliosis
Idiopathic scoliosis is commonly categorized by age of onset into:
● Infantile (0–3 years)
● Juvenile (3–10 years)
● Adolescent (10+ years)
Based on patient age, skeletal development, and deformity severity, different spinal fixation systems are selected for optimal results.
Atom Products:
4.5 Cobalt-Chromium-Molybdenum Pediatric Thoracolumbar Posterior Fixation System
Designed specifically for anatomical proportions of children, this system utilizes FGI (Functional Gradient Interface) coupling technology to achieve ultra-low notching and enhanced mechanical performance. A wide variety of hooks and growth rods provides highly personalized treatment options.
4.75 Cobalt-Chromium-Molybdenum Thoracolumbar Posterior Fixation System
Employing FGI technology, this system achieves ultra-low notching with improved biomechanical strength. Compared to traditional 5.5 mm titanium rod systems, its size is reduced by 27% while mechanical strength is tripled.
5.5 Cobalt-Chromium-Molybdenum Thoracolumbar Posterior Fixation System
Also featuring FGI technology, this system reduces overall volume by 15% compared to standard 6.0 mm titanium systems and enhances fatigue resistance by 229%.
About Atom
ATOM Medical Devices Co., Ltd. is a leading manufacturer of standardized orthopedic implants and instruments for global distributors and importers.
We offer a full product range covering trauma, spine, joints, sports medicine, and CMF — all supported by complete surgical instrument sets. Our products are designed for frequent orders, low MOQ, and fast turnaround, making them ideal for emerging markets and high-volume distribution.
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