- Discussion:
- extension type accounts for 95% of cases, & is caused by a fall on outstretched hand with hyperextension of the elbow;
- anterior periosteum is torn;
- there may be a significant amount of local bleeding and swelling;
- nerves & blood vessels are contused, compressed, or lacerated by bone fragments & blood that infiltrates the antecubital fossa;
- Gartland Classification:
- Type I: undisplaced;
- Type II: displaced with intact posterior cortex;
- Type III: displaced with no cortical contact;
- Fracture Anatomy:
- distal fragment is posteiorly displaced;
- in the sagittal plane, the fx line traverses obliquely upward and backward, and the frontal plane, it is frequently transverse;
- older pt, more oblique frx line tends to be in frontal plane;
- transverse fractures are more stable than oblique fractures;
- frx is usually complete, but occassionaly green stick frx occurs;
- distal fragment is displaced proximally & posteriorly;
- it is often tilted laterally or medially and rotated medially;
- lower end of proximal frag projects anteriorly, pierces periosteum, & forces its way into brachialis anticus & biceps brachii;
- periosteum is stripped from anterior surface of lower fragment and posterior surface of the upper fragment;
- degree of displacement of the fracture fragments is limited by the extent of periosteal stripping;
- most displaced frxs (Type III) are of extension type (97%);
- fractures of the extension type are associated with the most serious complications and the highest rate of residual cosmetic deformity;
- Treatment:
- Extension-type supracondylar fractures are initially splinted in 20 degrees of elbow flexion pending evaluation and treatment;
- Reduction
- intact posterior periosteum provides stability to the fracture and assists w/ reduction;
- position of maximum stability for reduction is full flexion and pronation;
- Non-displaced fractures are initially treated w/ immobilization in long arm splint with the elbow flexed;
- in non-displaced frx, the elbow should not be flexed > 90 deg;
- flexion of upto 120 deg renders frx more stable but also increases risk of neurovascular compromise;
- if neurovascular compromise has occurred, elbow must be gradually extended until neurovascular status of limb returns to normal;
- Percutaneous Pin Fixation
- Type III Supracondylar Frx