1 Definition: A supracondylar fracture of the humerus is a fracture which occurs in the distal third of the bone. The fracture line lies just proximal to the bone masses of the trochlea (1) and capitellum (capitulum) (2) and often runs through the apices of the coronoid (3) and olecranon fossae. The fracture line is generally transverse.

2 Occurrence: The supracondylar fracture is a common fracture of childhood; its incidence reaches a peak about the age of 8 years. It generally results from a fall on the outstretched hand, and should always be suspected when a child complains of pain in the elbow after such an injury.

3 Diagnosis: The olecranon and medial and lateral epicondyles preserve their normal equilateral triangular relationship (unlike dislocation of the elbow, also common in children). There is tenderness over the distal humerus, there may be marked swelling and deformity, and the child generally resists examination. Radiography is mandatory, but interpretation requires care.

4 Radiographs (a): Interpretation of radiographs of the elbow in children is made difficult by the changes produced by the successive appearance of ossification in the epiphyses. The old mnemonic ‘cite’ (capitellum, internal epicondyle, trochlea, ext. epicondyle) for appearance of the epiphyseal centres at 3, 6, 9 and 12 years is sufficiently accurate for normal purposes, but note that the capitulum may appear as early as the end of the first year.

5 Radiographs (b): Variations in appearances occur, and if there is any difficulty in interpreting the radiographs, there should be no hesitation in having films taken of the other side for direct comparison. These may for example draw attention to (1) the slight cortical irregularity of a minor greenstick fracture.

6 Radiographs (c): In fractures associated with more violence, the next detectable sign may be a hairline crack, visible in the AP view only (2). With more violence, the fracture line will be detectable in the lateral projection as well (3). Next, the distal fragment is tilted in a backward direction (4).

7 Radiographs (d): With still greater violence there is backward displacement (5), often leading to loss of bony contact. In the AP view there is often medial or lateral shift of the epiphyseal complex (M). The complex may also be rotated relative to the humeral shaft (generally lateral rotation). Rarely, as a result of other mechanisms the distal fragment is displaced and tilted anteriorly (A). Occult fractures may be suggested by the posterior fat pad becoming apparent in the lateral projections.

8 Vascular complications (a): Where there is appreciable displacement of the fracture, the brachial artery may be affected by the proximal fragment. In the majority of cases this is no more than a kinking of the vessel, but occasionally structural damage to the wall may occur, with the risk of Volkmann’s ischaemic contracture. (Rarely the neurovascular bundle is trapped between the fracture and the biceps tendon, with tethering of the overlying skin; this is an indication for exploration.)

9 Vascular complications (b): In every case check and record the circulation prior to any manipulation. Seek the radial pulse, and note any evidence of arterial obstruction (pallor and coldness of the limb, pain and paraesthesia in the forearm, and progressive weakness of the forearm muscles). Look for excessive swelling and bruising round the elbow. Neurological complications: Note any evidence of impaired function in the ulnar, median or radial nerves, said to occur in 6–16% of cases.

10 Interpretation of radiographs (a): Certain displacements showing in the lateral give a clear guide to the necessity for reduction.

11 Interpretation of radiographs (b): (4) If there is backward tilting (anterior angulation) of the distal fragment by 15° or more, then correction should be attempted. Note that in the normal elbow the articular surfaces of the distal humerus lie at 45° to the axis of the humerus. (The construction is shown and the actual deformity is 20° (45-25°).) Remodelling of persistent angulation is slow and may be poor, leading to loss of flexion.

12 Interpretation of radiographs (c): (5) Reduction is required if there is significant lateral or medial tilting. Note that the normal ‘carrying angle’ of the elbow is about 10°. (Illustrated is a cubitus varus deformity of 17° (10 + 7°). Cubitus varus and cubitus valgus do not remodel well, and may ultimately be associated with tardy ulnar nerve palsy. Some regard any degree of tilting as significant and meriting correction, and certainly a deformity of 10° and above is unacceptable.

13 Interpretation of radiographs (d): (6) Reduction is required if there is any significant rotational deformity. This is generally most obvious in the lateral projection. (Left above: no rotational (torsional) deformity present; Right: rotational deformity present.) Rotation, like cubitus valgus and varus, does not remodel well. In this context ‘significant’ is in effect any degree of rotation that is obvious in the plain films.

14 Classification of supracondylar fractures: Simple and useful is the Wilkins modification of the Gartland system: Type I: Undisplaced fracture; Type IIa: Greenstick fracture with anterior angulation (posterior tilting of the distal fragment); Type IIb: Greenstick fracture with anterior angulation and rotation; Type III: Completely displaced fracture. Types I and IIa do well, almost irrespective of treatment. Results are poorer in Type IIb and Type III, and internal fixation is preferred by many for injuries in these categories.

15 Summary of indications for reduction: Assuming no vascular complication, pure posterior displacement (1), lateral or medial displacement (2) of 50% or less, and angulation of less than 15° (3) may be accepted, as remodelling is generally rapid and effective. Rotation (4), valgus or varus (5), or loss of bony contact (6) require correction. In the next frames the techniques for closed reduction and cast fixation for any supracondylar fracture are followed by alternative methods using internal fixation.

16 Manipulation techniques (a): The arm should be manipulated under general anaesthesia. Gentle/moderate traction is applied at about 20° of flexion while an assistant applies counter-traction. This leads to disimpaction of the fracture. Some surgeons advise that this and the following stages should be carried out with the arm in supination.

17 Manipulation (b): Now maintaining traction and counter-traction (1) flex the elbow to 80° (2). This lifts the distal fragment, thereby reducing any posterior displacement and correcting any backward tilting (anterior angulation).

18 Manipulation (c): During this manoeuvre, the epiphyseal complex may be further coaxed into position by grasping it in the free hand. The thumb can be used to steady the proximal humeral shaft. Lateral displacement and torsional deformity (axial rotation) may also be corrected in this way.

19 Fixation (a): After reduction, the fracture must be maintained in a stable position. Flexion of the elbow stretches the triceps over the fracture, often splinting it most efficiently. The aim should be to flex the elbow as far as the state of the circulation at the time will permit, while making an allowance in anticipation of further swelling.

20 Fixation (b): Assuming that at 80° a pulse is present (if present before the manipulation it should still be there, and if first absent it will have hopefully been restored) continue flexion of the elbow until the pulse disappears (due to the elbow flexure crease along with the swelling compressing the brachial artery).

21 Fixation (c): Now extend the elbow slowly for about 10° beyond the point when the pulse returns. This is the position in which the arm should be maintained. If 110–20° or more of flexion can be preserved, a sling and body bandage, well secured with adhesive strapping, may suffice for fixation.

22 Fixation (d): Unfortunately further extension of the elbow may be required to restore the circulation. In such cases, apply a generous layer of wool (1), followed by a long arm plaster slab (2) secured with bandages and a sling (3). Many surgeons favour this in every case.Warning: never apply a complete plaster because of the risks of swelling, and avoid applying any pressure with encircling bandages at the front of the elbow – some skirt this area, only bandaging the cast into position above and below the joint.

23 Fixation (e): While the slab is being applied, the risks of recurrence of valgus or varus deformity may be reduced by careful positioning of the forearm: viz. if there has been valgus deformity (lateral tilting, medical angulation) (1) place the arm in supination. With varus (2) Place the arm in pronation. With insignificant angulation the neutral position may be employed.

24 Check radiographs: Check radiographs must now be taken in two planes. (For interpretation of AP radiographs, see later.) In the lateral projection illustrated there has been a good reduction: note how all posterior displacement has been corrected and the normal angulation of the epiphyseal complex has been largely restored. (For key see following frame.)

25 Check lateral radiographs ctd: This diagram is based on the previous radiograph, and shows correction of all posterior displacement (1), and restoration of the normal angulation of the epiphyseal complex (2). (F = fracture line; C = capitellum; R = radial head.) If a good reduction has been achieved:

1. discontinue the anaesthetic; 2. admit the child for overnight observation; 3. elevate the arm in a roller towel or similar device; 4. leave access in the dressings for observation of the pulse and finger circulation.

26 Late development of ischaemia: If while under observation the pulse disappears, and especially if there are other signs of ischaemia, all encircling bandages should be cut, and all wool in front of the elbow teased out. If this does not lead to improvement, the elbow should be placed in a more extended position (e.g. by cracking the slab and slackening the sling).

27 Absent pulse after manipulation: Returning to Frame 20: If after manipulation the pulse is not palpable, the elbow should be flexed to not more than 100° and maintained in that position with a sling and a back slab (applied over wool and held with a lightly applied bandage). The anaesthetic should be continued while check radiographs are taken.

28 Radiographs (a): If the radiographs show a poor reduction, then no more than two further attempts at manipulation may be permitted under the same anaesthetic. The illustration shows a typical unsatisfactory lateral projection where there is complete loss of contact between the distal fragment and the humeral shaft, with proximal displacement of the distal fragment (compare with Frame 24).

29 Radiographs (b): an AP projection should also be taken and the position checked in every case, even although faults in reduction demonstrated in the lateral projection are the ones more usually associated with circulatory impairment. As the AP view cannot be obtained with the elbow straight, superimposition of the radius, ulna and humerus make interpretation difficult (but see following frame). Be careful to avoid disturbing the reduction during the taking of these radiographs.

30 Radiographs (c): The epiphyseal complex preserves its relationship with the radius and ulna. In turn, with a good reduction, the radius and ulna regain their alignment with the humerus. Note in this unsatisfactory reduction the radius (R), ulna (U) and epiphyseal complex (E) are displaced medially in relationship to the humerus (H).

31 Radiographs (d): The preceding case with vascular impairment was remanipulated and the above correction obtained. This is a good reduction, and was accompanied by restoration of the pulse at the wrist.

32 Radiographs (e): A line drawing of the preceding radiograph is shown along with a sketch of the forearm bones drawn in roughly the same position (compare also with Frame 29). (R) = radius, (U) = ulna, (H) = humerus, (F) = fracture, (O) = olecranon, (M) = medial epicondyle.

33 Remanipulation: If a poor reduction has been obtained and remanipulation is necessary, the preceding technique may be repeated; alternatively, while an assistant applies light traction to the forearm, the distal fragment is pushed forwards with the thumb while the fingers control the proximal fragment. Plaster fixation may be applied as described before.

34 Absent pulse, adequate circulation: If a good reduction has been obtained and the pulse remains absent (this occurs in 3% of cases) the circulation should be checked more critically. The use of a pulse oximeter before and after manipulation is often helpful. If the hand is warm and pink, with good capillary return in the nails, there is no immediate indication for further intervention. Admission, elevation and close observation for 24 hours are essential. (Generally the pulse returns spontaneously over 2–3 days.)

35 Absent pulse, ischaemia: If there are incontrovertible signs of gross ischaemia, either in the face of a good reduction or a failed reduction, exploration of the brachial artery must now be undertaken. (Volkmann’s ischaemic contracture occurs roughly once in every thousand cases of supracondylar fracture, and is generally avoidable.) Exposure of the artery is straightforward. (i) A lazy S incision may be used, following the lateral edge of biceps and crossing the elbow near the fold.

36 Exploration of brachial artery ctd: (ii) The skin edges are reflected and the bicipital aponeurosis (1) divided close to the tendon (iii) The arm is put in full pronation and the space (5) between brachioradialis laterally (3) and pronator teres medially (4) opened up with the finger tips.

37 Exploration brachial artery ctd: (iv) The brachial artery (A) is found lying close to the biceps tendon. The median nerve (M) lies on its medial side. The fracture lies deep to the brachialis (B) in the floor of the wound. In some cases relief of local pressure on the vessel (e.g. from the fracture) may restore the circulation, but other measures, requiring experience in vascular surgery, may be necessary.

38 Reduction failure with satisfactory circulation (a): it is unwise to repeat manipulation beyond the third attempt owing to the risks of increasing swelling. In these circumstances, marked displacement (but not angulation, valgus or varus) may be accepted, relying on later remodelling. The fracture illustrated had no bony contact (completely off-ended) in the lateral: after a year, considerable remodelling has occurred, with loss of 15° only of flexion.

39 Reduction failure (b): If displacement and angulation are outside acceptable limits, open reduction is not generally recommended. Instead, continuous traction may be employed. This is especially indicated where there is minimal circulatory impairment, brachial artery exploration is not indicated, and the elbow cannot be flexed. In Dunlop traction, traction tapes are applied to the limb. (W) = wool; (C) = lightly applied crepe bandage.

40 Reduction failure (c): The arm is abducted at the shoulder and traction of 1.5 kg applied with the elbow at 60° flexion. Counter-traction of 1 kg is applied directly with a canvas sling applied well above the elbow to avoid compression in this vulnerable area. After swelling subsides the situation may be re-appraised, or the traction discontinued and a plaster slab substituted at 2–3 weeks.

41 Reduction failure (d): As an alternative to Dunlop traction (and also as a routine treatment) Gadgil et al¹ recommend straight arm traction with the arm in 90° abduction and the shoulder elevated from the bed, using skin tapes applied under opiate analgesia. Minor adjustments allow good control of any tendency to cubitus varus or valgus. Weekly radiographs are taken, and traction stopped when the patient can actively flex the elbow. The best results were obtained in children under 10 years, and a disadvantage is the time in hospital.

42 Reduction failure (e): Alternatively skeletal traction may be employed: this may be achieved with a butterfly (wing) screw or similar device in the ulna. Traction is applied with weights, and the forearm supported with a sling. Elbow flexion may be controlled with the sling which may be elevated or lowered as thought necessary: this avoids any direct pressure in the antecubital fossa.

43 Alternative fixation using a skeletal traction brace: Matuszaki et al² detail a system which they describe as being easy and safe. A winged screw is inserted into the olecranon, and a spring applies traction. The amount of traction is adjustable by a knurled nut, and the direction of the pull by the position of the traction hook in the wing. Counter traction is provided by a splint which allows for adjustment of the axillary component. The components are radiolucent, making X-ray supervision easy, and it is normally worn for 3–4 weeks.

44 Alternative fixation technique (a): This is recommended (where image intensification is available) for all fractures where it is difficult to maintain a reduction. Many advise it for all Type IIa and Type III fractures. Begin by reducing the fracture by traction and elbow flexion as described; with the elbow flexed, correct any rotation. Now flex the elbow fully and insert a K-wire laterally, aiming for the axilla (1). Extend the elbow to 90°, locate the ulnar nerve by a small incision over it, and insert a second medial K-wire above it (2).

45 Alternative fixation technique ctd: The K-wires (a) should not be less than 1.6 mm in diameter, and should engage the opposite supracondylar ridge (b). They may cross the growth plate without causing any obvious growth problem. They should remain proud of the skin (c). Single wire fixation is less secure and is not recommended. Additional support with a cast and sling is recommended. The wires may be removed as an out-patient procedure, without anaesthetic, after 3–4 weeks.

46 Alternative fixation technique (b): To reduce the risk to the ulnar nerve and to avoid having to expose it, two K-wires may be inserted from the lateral side (after reduction and under intensifier control), maximally separated at the level of the fracture. The anatomy dictates that they should be directed slightly posteriorly. (Note that it is acceptable for the pins to cross the olecranon fossa.) If some instability remains on light stressing, a third wire (lying in the area between the two pins shown) should be inserted.

47 The anterior (reversed) supracondylar fracture (a): Supracondylar fractures in which the distal fragment is displaced anteriorly are comparatively uncommon. The normal angle (45°) between the epiphyseal complex and the shaft is increased. This deformity is aggravated by flexion of the elbow.

48 Anterior supracondylar fracture (b): An uncommon but related injury is the more distally situated traumatic separation of the epiphyseal complex (Salter & Harris Type 1 or 2) in which the displacement is identical. To reduce either of these injuries, light traction is applied to the elbow in the flexed position (1). This disimpacts the fracture (2).

49 Anterior supracondylar fracture (c): Continuing the traction (1) the elbow is slowly extended (2), reducing the angulation (3). The arm is put in a plaster back slab in a position of 10° flexion (4). This position should not be maintained for more than 3 weeks. At that stage the elbow should be gently flexed (usually about 70–80° can be achieved) and supported either with a sling or further slab until it is united.

50 Anterior supracondylar fracture (d): An alternative technique is to apply wool to the limb (1) and disimpact the distal fragment by direct traction on the epiphyseal complex (2). A plaster cuff (3) is then applied by an assistant and allowed to set. Care must be taken to avoid ridging at the distal end (4) which has the potential for causing circulatory impairment.