Forearm bone fractures is a huge topic. In my opinion, the best way to present forearm bone fractures is to stress on the important information related to these fractures. The important topics for the forearm bone fractures are treatment and indication for surgery, open reduction internal fixation, treatment of nonunion, malreduction, radial bow, retained hardware, heterotopic ossification (HO), and compartment syndrome. For treatment and indication for surgery, the acceptable alignment in both bone forearm fractures is related to the age of the patient and the location of the fracture. In children younger than 9 years old, an angulation less than 15 degrees and malrotation less than 45 degrees is acceptable. If the patient is 10 years old or older, and the angulation is more than 10 degrees, then this is not acceptable. The surgeon may accept bayonet apposition as long as the angular and rotational deformities are within the acceptable limits. In adults, conservative treatment with a functional brace is utilized for the ulna if there is less than 50% displacement and less than 10 degrees angulation, because the union of the fracture is high with or without surgery. In general, fractures of the radius and the ulna are treated surgically, except for the isolated, nondisplaced fracture of the ulna or fracture of the distal 2/3 of the ulna such as seen in the nightstick fracture, especially in fractures with less than 50% displacement and less than 10 degrees of angulation. An example would be for a 10 year old patient with midshaft fractures of both forearm bones (ulna and radius). You will do closed reduction and you need to achieve acceptable parameters. If you get 10 degrees of malrotation, 10 degrees of angulation and bayonet apposition, then you will place the patient in a long arm cast and follow up with the patient in a few days to check the alignment. If you have an isolated fracture of the ulnar shaft 10 cm proximal to the distal radioulnar joint (DRUJ) with in 2 mm of displacement, you do conservative treatment, no surgery. There is no difference in the outcome between surgical and nonsurgical treatment (patient may be treated by a functional brace). Another example would be a 12 year old patient that has a fracture of the radius and the ulna. You will do closed reduction for the patient and cast immobilization. Use a long arm cast because it provides better control of the deforming forces. If a child has a fracture located within the distal 1/3 of the forearm, then you can use a short arm cast. The cast index x-ray measurements are defined by the sagittal width divided by the coronal width of the cast and should be < 0.8 to ensure that good molding of the cast occurs and so that the cast is firmly applied and not loose. If the fracture is displaced 20 degrees with angulation in the 12 year old patient, the treatment will be surgery, either use an IM rod or ORIF. In adolescence, you can use the IM flexible nail or plates. Both have the same radial bow reduction, the same rate of union, the same forearm rotation. The operation for inserting flexible nails is shorter and has less blood loss. In general, operative treatment of an adolescent patient with forearm bone fractures is preferred over cast treatment. If you use conservative treatment, assessment of rotation is important by checking the position of the radial styloid process and the biceps tuberosity. The radial styloid process and the biceps tuberosity are oriented 180 degrees. Loss of forearm rotation is the most common complication for operatively treated forearm fractures.
