Osteomyelitis usually occurs at the ends of a patient's humerus, more often at the upper than the the lower end. You can expose and drill them through quite limited incisions; the upper end anteriorly and the lower end either anteriorly or posteriorly. If absolutely necessary (rare), and if you cannot refer him, you can expose his humerus from end to end by approaching it from the antero-lateral side.
The main danger is that you may injure his radial nerve, as it winds round his humerus posteriorly. If you are working near it, find it first so that you can avoid it.
Proximally, enter his arm between his pectoralis major and his deltoid. Distally, enter it between his brachioradialis and his biceps. As you do so, retract his radial nerve laterally, and his musculo-cutaneous nerve medially with his biceps.
Fig. 7-7 OSTEOMYELITIS OF THE HUMERUS. A, the approach for the upper end. B, the anterior approach to the lower end. C, the posterior approach to the lower end. D, the incisions to approach the ends of the bone. E, a cross section a little below the mid point of the arm above the origin of brachioradialis, to show the approach to the middle of the shaft and the position of the radial nerve.
OSTEOMYELITIS OF THE HUMERUS Follow the general methods for osteomyelitis, in Sections 7.4 to 7.6. Always apply a tourniquet for operations on the middle (difficult in a young child) or lower third of the humerus.
PROXIMAL END. Approach this in the patient's deltopectoral groove. Find his cephalic vein, and try to displace it medially. If necessary, tie it proximally and distally.
Reflect his deltoid laterally, and expose his humerus by using two pairs of bone levers. Both the heads of biceps, and coracobrachialis lie medial to the insertion of the tendon of pectoralis major.
DISTAL END, POSTERIOR APPROACH. Make a midline incision in the posterior surface of his lower arm, and end it 3 cm above his epicondyles, so as to avoid his olecranon pouch. Don't extend the incision up into the middle third of his arm, or you will injure his radial nerve. Divide the tendon of his triceps and the muscle under it to expose his humerus.
DISTAL END, ANTERIOR APPROACH. Open his arm between his brachioradialis laterally, and his biceps medially, as in B, Fig. 7-7. Separate these muscles by blunt dissection, find his radial nerve and leave it laterally. Incise his brachialis medial to the nerve and expose his humerus. Retract his muscles by placing two pairs of bone levers subperiosteally.
If necessary, you can split his brachialis to within two fingers' breadth of his epicondyles without entering his elbow joint. Don't extend the incision beyond the flexor crease of his elbow, because you may cut his radial artery.
THE SHAFT OF THE HUMERUS. Refer him if you can. If you cannot refer him, put a sandbag under his shoulder on the same side. Drape his whole arm. Extend the approach to his upper humerus distally, or the lower anterior approach proximally.
Distally, divide the deep fascia to expose division between biceps and brachialis. His musculo-cutaneous nerve lies between these muscles. Displace it medially with his biceps. Separate his biceps and his brachialis and find his radial nerve. Above the origin of his brachialis, it lies between biceps and his triceps and winds posteriorly round his humerus in his radial groove.
Postoperatively, put his arm in a sling and encourage active movements within the confines of the sling, or apply a backslab.