- Discussion:
- has become standard technique for stabilizing
types II &
type III frx;
- either two lateral pins, or one lateral and one medial pin may be used and both should penetrate the cortex;
- medial and lateral pin insertion provides better stabilization;
- 2 lateral pins may not permit full elbow extension, thus preventing full assessment of carrying angle;
- Radiographs:
-
Baumann's Angle
- radiographs of uninjuried side:
- Pinning Technique:
-
reduction technique:
- in preparing for crossed pinning, keep elbow hyperflexed to maintain reduction;
- consider applying sterile "coband" to keep elbow flexed, which then allows arm to be externally rotated to achieve a lateral view w/o moving flouro;
- pins should cross proximal to the frx at an angle of about 30 deg to the humeral shaft;
-
positioning:
- w/ posteromedial displacement, place arm in maximum external rotation on the flourscopy platform, and insert the medial pin first;
- w/ posterolateral displacement, place arm in maximum internal rotaiton on the flourscopy platform, and insert the lateral pin first;
-
pin size:
- pins need to be smooth w/ trochar point;
- w/ children younger than 5-6 years, use 0.062 smooth K wire;
- in older children use 5/64 K wires;
-
lateral pin: 
- avoid directing pins too far anterior or posterior;
- insertion point is in the center of lateral condyle (capitellum);
- because the center of the capitellum is in line w/ anterior aspect of humeral shaft, the pin must be directed
slightly posteriorly;
- wire is inserted thru the capitellum, and then the distal humeral physis;
- generally, the pin is aimed 35 deg upward and 10 deg posterior;
- pin should avoid the olecranon fossa and should come to rest along the far cortex;
- some surgeons always insert the lateral pin first to obtain stability while the reduction is evaluated (this avoids the need to repeatedly
insert medial pins if the reduction is not adequate);
- consider placing a temporary 2nd pin thru the lateral condyle to achieve even more stability;
- in the report by
DL Skaggs et al (JBJS Vol 83A: 735-740), authors reviewed the results of K wire fixation of 345 extension-type supracondylar frx;
- configuration of the pins did not affect the maintenance of reduction of either type-2 fractures or type-3 fractures;
- ulnar nerve injury was not seen in the 125 patients in whom only lateral pins were used;
- use of a medial pin was associated w/ ulnar n injury in 4% patients in whom the pin was applied w/o hyperflexion of the elbow
and in 15% in whom the medial pin was applied w/ elbow hyperflexed;
- 2 years after the pinning, one of the 17 children with ulnar nerve injury had persistent motor weakness and a sensory deficit;
- fixation with only lateral pins is safe and effective for both Gartland type-2 and Gartland type-3 (unstable) supracondylar frx;
- authors note that if a medial pin is used, the elbow should not be hyperflexed during its insertion;
- ref:
Prevention of ulnar nerve injury during fixation of supracondylar fractures in children by 'flexion-extension cross-pinning' technique.
-
medial pin:
- passed obliquely thru medial epicondyle, just proximal to olecranon fossa;
- need to protect
ulnar nerve;
- note that w/ flexion, the ulnar nerve can sublux over the medial condyle placing it at risk w/ medial pin insertion;
- because of ulnar nerve subluxation, some surgeons always place the lateral pin first (w/ elbow hyperflexed) which confers stability;
- once the lateral pin has been inserted, the surgeon can then bring the elbow out to 80-90 deg flexion (decreasing ulnar nerve subluxation)
prior to placement of the medial pin;
- the surgeon's thumb can milk the ulnar nerve back into its posterior position and hold it there;
- if excessive soft tissue swelling is present, then consider making a small incision thru the skin over the medial epicondyle, and then spreading w/ hemostat;
- use soft tissue protector from the cannulated screw set inorder to further protect the ulnar nerve;
- because medial epicondyle is slightly posterior to the shaft, direct the medial pin slightly anterior;
- also ensure that the medial pin enters straight into the epicondyle rather than distal to the epicondyle;
- the medial wire will often appear more transverse than the lateral pin;
- in the report by
DL Skaggs et al (JBJS Vol 83A: 735-740):
- use of a medial pin was associated w/ ulnar n injury in 4% patients in whom the pin was applied w/o hyperflexion of the elbow
and in 15% in whom the medial pin was applied w/ elbow hyperflexed;
- 2 years after the pinning, one of the 17 children with ulnar nerve injury had persistent motor weakness and a sensory deficit;
- authors note that if a medial pin is used, the elbow should not be hyperflexed during its insertion;
- after pin placement assess carrying angle to r/o
cubitus varus
-
Baumann's angle, angle between long axis of humeral shaft & growth plate of capitellum, will suggest final carrying angle after reduction;
- finally, re-check the radial pulse and the quality of the pulse;
- Post Op:
- pins can usually be removed a 3 weeks post op;
- Case Example:
- 7 year female who presented with a displaced supracondylar fracture - an attempt at closed reduction was carried out, but the reduction was unacceptable;
- open reduction was carried out via limited medial and lateral incisions;
- Example:
- these pictures show residual displacement following closed reduction and pin fixation;
Supracondylar fractures of the humerus in children. A modified technique for closed pinning.
Supracondylar fractures of the humerus. A comparative study of Dunlop's traction versus percutaneous pinning.
Percutaneous fixation of supracondylar fractures of the humerus in children.
Difficult supracondylar elbow fractures in children: analysis of percutaneous pinning technique.
K-wire fixation of supracondylar humeral fractures in children: results of open reduction via a ventral approach in comparison with closed treatment.
Deformity and function in supracondylar fractures of the humerus in children variously treated by closed reduction and splinting, traction, and percutaneous pinning.
Torsional Strength of Pin Configurations Used to Fix Supracondylar Fractures of the Huerus in Children.
Supracondylar fractures of the humerus in children treated by closed reduction and percutaneous pinning.
Clinical evaluation of crossed-pin versus lateral-pin fixation in displaced supracondylar humerus fractures.
Supracondylar fractures of the humerus: A prospective study of percutaneous pinning. DW Boyd and DD Aronson. J. Pediatric Orthop. Vol 12. 1992. 789-794.
Operative Treatment of Supracondylar Fractures of the Humerus in Children. The Consequences of Pin Placement David L. Skaggs, MD. JBJS (Am) 83:735-740 (2001)
Lateral-Entry Pin Fixation in the Management of Supracondylar Fractures in Children.
Reduction and pinning of pediatric supracondylar humerus fractures in the prone position.
Lateral Entry Compared with Medial and Lateral Entry Pin Fixation for Completely Displaced Supracondylar Humeral Fractures in Children.
Loss of Pin Fixation in Displaced Supracondylar Humeral Fractures in Children: Causes and Prevention.
Three Lateral Divergent or Parallel Pin Fixations for the Treatment of Displaced Supracondylar Humerus Fractures in Children.
