Plating with precontoured periarticular locking plates provides angular-stable fixation and is the most commonly used method of distal humeral fracture fixation.
The plate should be applied in a compression mode on the side where the fracture plane exits proximally. If more stability is required, a second plate may be applied on the other side.
In the following, the treatment of an obliquely distal and medial fracture is described. The obliquely distal and lateral fracture is treated analogously.
The mechanical properties of the distal humerus are based on a triangle of stability, comprising the medial and lateral columns and the articular block (see also the anatomical concepts).
In principle, for extraarticular fractures, the side of the triangle with the simplest fracture is fixed first.
Precontoured anatomical plates have been designed. If these are not available, a precontoured one-third tubular plate may be used on the crest of the medial supracondylar ridge, and a reconstruction plate on the posterior or lateral aspect of the lateral column. If a stronger plate is required for either column, a small-fragment compression plate may be used, but this is more difficult to contour.
In this procedure, the lateral plate has been chosen to capture the lateral apex of the distal fragment. If the apex is more posterior, a dorsolateral plate may be preferred.
This procedure is normally performed with the patient either in a prone position or lateral decubitus position.
For this fracture pattern, either a triceps-split or paratricipital approach may be used.
If only a lateral plate is to be used, a triceps-on approach is preferred.
If both columns are to be fixed, a triceps-split approach may be preferred.
Reduce the main fragments anatomically with manual traction and maintain reduction with a reduction forceps.
Preliminary fixation with axial K-wires may be helpful. To avoid risk to the ulnar nerve, parallel K-wires from laterally may be preferred.
If necessary, check the reduction and provisional fixation with image intensification.
The basic technique for application of anatomical plates is described in:
If precontoured anatomical plates are not available, see the basic technique for application of reconstruction plates.
Apply a lateral or dorsolateral plate first in compression mode as this is easier to accomplish.
This plate also acts in an antiglide function.
For further stability, apply a medial plate in either compression or neutral mode (antiglide).
If the fracture pattern and bone quality allow, insert a lag screw perpendicular to the fracture plane through the plate.
Visually inspect the fixation and manually check for fracture stability.
Repeat the manual check under image intensification.
Ensure the ulnar nerve is not unstable or tethered on implants throughout a full range of motion.
The rehabilitation protocol consists usually of three phases:
The arm is bandaged to support and protect the surgical wound.
The arm is rested on pillows in slight flexion of the elbow so that the hand is positioned above the level of the heart.
Short-term splinting may be applied for soft-tissue support.
Neurovascular observations are made frequently.
Hand pumping and forearm rotation exercises are started as soon as possible to reduce lymphedema and to improve venous return in the limb. This helps to reduce postoperative swelling.
Gravity-eliminated active assisted exercises of the elbow should be initiated as soon as possible, as the elbow is prone to stiffness:
Active patient-directed range-of -motion exercises should be encouraged without the routing use of splintage or immobilization.
Avoid forceful motion, repetitive loading, or weight-beating through the arm.
A simple compressive sleeve can provide proprioceptive feedback which can help regain motion and avoid cocontraction.
No load-bearing (ie, pushing, pulling, or carrying weights) or strengthening exercises are allowed until early fracture healing is established by x-ray and clinical examination.
This is usually a minimum of 8–12 weeks after injury. Weight-bearing on the arm should be avoided until bony union is assured.
The patient should avoid resisted extension activities, especially after a triceps-elevating approach or olecranon osteotomy.
When the fracture has united, a combination of active functional motion and kinetic chain rehabilitation can be initiated.
Active assisted elbow motion exercises are continued. The patient bends the elbow as much as possible using his/her muscles while simultaneously using the opposite arm to gently push the arm into further flexion. This effort should be sustained for several minutes; the longer, the better.
Next, a similar exercise is performed for extension.
If the patient finds it difficult to accomplish these exercises when seated, then performing the same exercises when lying supine can be helpful.
Generally, the implants are not removed. If symptomatic, hardware removal may be considered after consolidated bony healing, usually no less than 6 months for metaphyseal fractures and 12 months when the diaphysis is involved. The avoidance of the risk of refracture requires activity limitation for some months after implant removal.
AP and lateral view of an extraarticular oblique fracture with parallel bicolumnar plate fixation