Anatomy of the radius and ulna bones
the radius and ulna bones are formed the bone of the forearm which extend from elbow joint above to wrist joint below the radial bone is longer than the ulnar bone both bones run parallel to each other the radius articulated with the capitulum of the humerus bone by radial notch and head of the ulna and forming superior or proximal radioulnar joint the radius called that because it acts like radius(of a circle) the ulna acts as the

anatomy of the radius and ulna
center point to the circle because when arm is rotated the ulna
does not move and the radius acts like radius or circle and rotates around the ulna at distal end of the radius there is styloid process which articulate with the bone of the wrist the ulnar bone is shorter than the radius it lies medial to the radius and it is articulate above with trochlea of the humerus with trochlear notch and below with the radius by ulnar notch forming inferior or distal radioulnar joint also articulated with radius along its length by interosseous membrane that forming syndesmoses joint
In this section it will be including the following fractures 1- Forearm fractures 2-Distal radius fractures 3- Radial head fractures 4-Olecranon fractures 5- Elbow dislocation

Forearm Fractures

The radius and ulna are the two bones of the forearm. Motor vehicle accidents, sports injuries, falls, or direct blows to the forearm may cause a fracture to one or both of these bones. The fracture may or may not have a significant associated soft-tissue or joint injury. Fractures of both bones of the forearm are described by their loca­tion (proximal, midshaft, or distal), by the amount of displacement(minimal, moderate, or complete), the degree of angulation. the ex­tent of comminution. and whether the fracture is open (compound) or closed fractures.

A fracture of the ulna with an associated dislocation of the radial head was first described by Monteggia in 1814 (before radio­graphs were discovered) and is now known as a Monteggia fracture . A fracture in the distal third of the radius with an associated dislocation of the distal radioulnar joint is called a Galeazzi fracture after the physician who, in 1934, described this combina­tion of injuries . An isolated fracture of the ulna is called a nightstick fracture because being hit by a nightstick was a common mechanism of injury.Rotation of the forearm is crucial to the proper positioning and function of the hand, and is therefore important in activities of daily living (ADL). Normally, the radius rotates around the fixed ulna. The ability of the radius to rotate around the ulna depends on the
normal shape of each bone. The ulna is relatively straight while the radius is bowed. Restoration of this normal anatomy after fracture is imperative for a return to full function. A deformity in the proximal forearm has a relatively greater effect of forearm rotation when com­pared to the more distal deformity. Therefore, management should restore the normal anatomy and hold the bones in this position until the fractures heal.

Individuals with displaced or angulated fractures of the forearm will present with pain. swelling, and deformity. The neurovascu­lar status of the forearm and band should be determined. Antero­posterior and lateral radiographs are usually all that are needed to demonstrate the fractures. The elbow and wrist should be examined and both should be seen on the radiographs to look for fractures or dislocations in one of these joints. In cases of suspected injury to the proximal or distal radioulnar joints, a CT scan may be of value.
While displacement, angulation. and shortening are easily seen on routine radiographs, rotational alignment is not easily determined. If. on the anteroposterior view, the radial styloid (lateral) and bicip­ital tuberosity (medial) are both evident and prominent, rotational alignment is present in the supinated radius. In the lateral view. the coronoid process of the ulna points anteriorly and the ulna styloid posteriorly. Recognizing a dislocation of the radial head from its normal articulation with the humeral capuellum can be difficult. A line perpendicular to the articular surface and through the cen­tral position of the radial head should bisect the capitellum. This relationship should be seen on all projections if the radial head is anatomically located.

Generally. forearm fractures are treated with a closed manipulation and cast immobilization for children and open reduction and internal fixation in adults. It is generally true that the younger the patient. the greater the remodeling potential and the less need for an immediate anatomic reduction. In addition, the thicker pe­riosteum seen in children usually remains intact or partially intact and makes it easier to reduce and hold the reduction compared to those in adults. A unique feature of immature bone is the capacity to undergo plastic deformation without,breaking and to sustain an incomplete fracture called a (greenstick ) fracture.

To reduce a displaced. angulated. both-bone forearm fracture requires anesthesia or sedation. The forearm is manipulated to re­duce the displacement and the arm is placed in a long-arm cast The more proximal the fracture the more the patient's forearm should be placed in supination. A midshaft fracture is placed in neutral rota­tion and a distal forearm fracture is Immobilized by mild pronation.

They are kept in a long-arm cast for at least 6 weeks. Callus should be visible before removing the cast. The cross section of the cast should be oval with the anteroposterior distance being less than the medial to lateral distance. This remains the interosseous distance and helps hold the reduction.

Plastically displaced bones are reduced by gradual, sustained force to straighten the bent bone. Greenstick fractures are completed so that they can be properly aligned. Both types of fractures are held in a long-arm cast. In children, bringing the ulna out to length and correcting the angulation reduces the Monteggia fracture. This reduces the radial head in almost all cases. The patient is then placed in a long-arm cast with the elbow flexed to at least 100 degrees and the forearm in a semisupinated position. Galeazzi fractures in children are usually Stable after a closed reduction of the radius and can be held in a long-arm cast with the forearm supinated and wrist neutral.

Displaced, both-bone forearm fractures in adults are usually un­stable and are best treated with open reduction and internal fixation. Malunion and delayed union rates are unacceptably high with closed treatments. In addition. the length of immobilization is such that prolonged stiffness occurs. This dramatically lengthens the period of disability. Compression plating with 3.5 mm plates is the most accepted form of internal fixation. Both bone forearm fractures are fixed with two plates, one on each bone . Plate fixation of the bony fracture in an adult with a Monteggia fracture or Galeaz.zi fracture is 
recommended and usually reduces the joint disdlocation

 Summary of Specific injuries

Monteggia fractures Proximal ulna fractures may be associated with dislocation of the radial head but these account for only 1% of forearm fractures. If the ulna fracture IS reduced accurately. the radial head usually reduces and no specific treatment is necessarv .

Galeazzi fractures Again these are relatively uncommon and con­sist of a distal radial fracture with disruption of the distal radio­ulnar joint. Open reduction of the distal radius is carried out and the reduction of the distal ulna confirmed. If this is unstable immobilisation in supination or even cross pinning to the radius is carried out 

Distal Radius Fractures 
Fractures of the distal radius are among the most common fractures encountered in children and in adults. There is a bimodal peak of incidence occurring in later childhood and after the sixth decade of life. Fractures in males contribute a greater number to the earlier peak, while fractures in females predominate in the later years. The most common mechanism of injury in both children and adults is a lower-energy fall from ground level onto an outstretched hand with the wrist extended. Fractures that do occur from higher-energy injuries have varying degrees of comminution, may occur in any age group, and have a higher incidence of associated injuries. Anteroposterior, lateral, and possibly oblique radiographs are usually all that are needed to assess distal radius fractures. in the presence of comminution and intra-articular involvement, a CT scan may be of use to assess the status of the radiccarpal, and especially the ra­dioulnar, joints. Patients with distal radius fractures present with pain. swelling, and deformity. Examination must include a neurologic assessment prior to and after reduction of the fracture.

Even though numerous newer classification schemes have been
introduced, eponyms have endured as the most common way of referring to these fractures in adults, and thus are reviewed here. They usually communicate location and direction of displacement, but do not aid in determining the type of treatment nor prognosis. the Colles-Pouteau fracture denotes a fracture of the distal radial metaphysis with dorsal or posterior displacement of the distal fragment  or displacement of the hand and wrist the fractures sometimes is referred as a dinner fork or bayount deformity  coll,s fractures are common seeying in osteoporotic peoples and is by far the most common fracture of the distal radius In contrast, the direction of displacement of the Smith-Goyrand meta­physeal fracture is volar or anterior called smith fractures. A dorsal articular marginal fracture (the volar portion of the articular surface is still intact to the shaft of the radius) is referred to as a Barton's fracture. In a volar Barton's frac­ture (also referred to as Letenneur's fracture), the articular fracture is volar or anterior. A fracture of the radial styloid is referred to as a Hutchinson's or Chauffeur's fracture.

Numerous. more recent fracture classifications have been developed. but no one classification scheme has gained wide acceptance over the others. These classifications have delineated whether the fractures are intra-articular or extra-articular, have differing fracture patterns, the presence and location of comminution, associated ulnar styloid fracture, and have sought to predict the degree of stability and determine the best course of treatment and prognosis

In children, the distal radius fractures are grouped into metaphyseal (more common) and physeal fractures. The metaphyseal fractures may be complete or incomplete (buckle or torus fracture). The physeal fractures are described according to the Salter-Harris classification. The majority of these fractures in children are treated by closed means. Buckle fractures are treated in plaster for 4 weeks. Angulated and/or displaced fractures are manipulated and kept in a cast for 6 weeks. Because of an intact periosteum on one side of the metaphyseal fracture. traction prior to manipulation may be of little help, and. infact. may be counterproductive in completely displaced fractures. If at least 2 years of growth remain. up to 20 de­grees of angulation may be accepted because remodeling will occur. Similarly. even bayonet apposition (side-to-side alignment of the fracture fragments) in the absence of severe angulation or rotatory deformity will remodel Without residual functional deficits. Physical injuries are reduced by gentle distraction and manipulation avoid­ing repeated attempts and possible further physeal injury. Unstable. severely displaced. and angulated metaphyseal or physical fractures may necessitate closed or open reduction accompanied by internal fixation (usually smooth K-wires) or external fixation in order to prevent loss of reduction.

The aim of treatment of distal radius fractures in adults is to restore the general alignment of the distal radius and ulna, avoid­ing radial shortening of greater than 3 to 5 mm, residual angulation greater than 10 to 15 degrees, and articular incongruity of greater than 2 to 3 mm. The degree of residual deformity accepted will de­pend on the age and functional needs of the individual patient. The majority of these fractures are extra-articular or have a minimally displaced. intra-articular component. and are treated successfully by closed reduction followed by 6 weeks of protection in a cast, splint, or brace. Closed reduction is obtained by finger-trap traction followed by manipulation and application of the splint of choice, usually under hematoma-block local anesthesia. Fractures with se­vere shortening, angulation. and comminution are usually unstable and require some form of fixation. Displaced intra-articular fractures such as volar Barton's or radial styloid fractures are also unstable and require some form of fixation in order to restore articular con­gruity. Fixation may be obtained by internal fixation (pins, wires, screws, or plates), by percutaneous fixation (pins or external fixa­tion), or by varying combinations of each method. Arthroscopically assisted fracture reduction and augmentation with bone graft or ce­ment materials also have been used. The most common complications of this method of reduction include malunion, nerve injury, tendon injury, stiffness, and reflex sympathetic dystrophy. If a malunion causes pain and significant limitation of motion and function, an osteotomy may be used to correct this situation. Early and tardy nerve symptoms. most com­monly median nerve/carpal tunnel syndrome, can be treated by the appropriate release. Tendons might be entrapped. requiring a re­lease or ruptured. requiring a repair or transfer. Finger stiffness and pain, whether associated with swelling in the early post fracture pe­riod or as part of a reflex sympathetic dystrophy, require early and aggressive intervention by the occupational therapist

Radial head fractures

These are relatively common fractures; the majority occurs in females, in the age group 20-50 years, after a fall on the out­ stretched hand.

Approximately 40% of fractures are undisplaced, involving
only part of the articular surface. In a further 40% a fragment of the radial head is displaced, with depression of the articular sur­face. The remainder of the fractures involves all of the articular surface, either as a Single fragment with a fracture of the radial neck or as a comminuted fracture of the radial head.

Some fractures are not visible on plain radiographs, although evidence of an effusion can often be seen. This injury should be suspected in patients with a typical history, pain over the radial head and restricted movement of the elbow.


A number of classifications has been described but one of the most commonly used is that described by Mason

type 1 - undisplaced partial articular (marginal) fractures

type 2 - displaced marginal fractures

type 3 - comminuted fractures of the radial head


Undisplaced fractures are treated by a temporary collar and cuff support, followed by early mobilisation. If the elbow is particularly painful, aspiration of the haemarthrosis can be carried out followed by intra-articular injec­tion of local anaesthetic. Aspiration can be safely carried out through the centre of the triangle formed by the lateral epicondyle, radial head and the olecranon.

The treatment of displaced, partial articular fractures is dependent on the size and displacement of the fragment. Small frag­ments < 25% of the articular surface) are treated conservatively, unless the range of motion is significantly restricted. In these cir­cumstances aspiration of the joint and injection of local anaes­thetic is carried out. If there is still a block to extension, and particularly full supination, exploration of the elbow via a lateral incision is indicated. Large fragments are treated by open reduc­tion and internal fixation with small screws if possible; smaller fragments can be excised.

More complex injuries are treated by internal fixation,
although this may not be possible if significant comminution is present. In these circumstances excision of the radial head can be carried out. If, however, there is any damage to the collateral ligaments of the elbow or the interosseous membrane of the forearm, prosthetic replacement may be indicated. This is seen in patients sustaining high-energy injuries, such as road traffic accidents or falls from a height. In these patients, radiographs of the entire forearm including wrist should be obtained, and the distal end of the radius examined carefully, both clinically and radiologically.

Summary of Radial head fractures

• a 40% are undisplaced - aspirate blood. Mobilise within the limits of pain

• Small fragments or minimal displacement are treated non·operatively

• large fragments or major displacement or blocks to movement require internal fixation

If fixation is not possible the radial head should be excised

Olecranon fractures

These are common injuries and are usually due to indirect trauma such as a fall on the outstretched hand. The injury is essentially an avulsion fracture due to the pull of the tricep­s muscle. Most fractures are intra-articular, although extraartcular­ fractures do occur with a small bony fragment avulsed


A number of classifications has been described but the main factors that determine the treatment are the location and displacement of the fracture, and the number of fragments.

Treatment Undisplaced fractures can be treated conservatively, but late displacement can occur and regular review is necessary. most fractures are displaced and internal fixation is indicated. Extra articular and two-part intra-articular fractures can be treated with a tension band wiring system, using a figure-of-eight wire and intramedullary wires or screws Stable internal fixation should be achieved to allow early mobilisation of the elbow. A tension band wire is not suitable for comminuted articu­lar fractures or more distal fractures. and plate fixation is recom­mended.

The prognosis for this injury is good, with a full functional recovery expected. The metal is often prominent and can be troublesome. It can be removed. if necessary. after the fracture has healed.

Summary of Olecranon fractures

• Undisplaced are treated non-operatively

• Displaced two-part fractures can be treated with a figure-of-eight tension band

Elbow dislocation

Approximately 20% of all dislocations occur at the elbow and most occur in children and young adults. The elbow usually dislocates posteriorly and is due to axial loading on a slightly flexed elbow. Fractures of the distal humerus. radial head and coronoid may be associated with the injury .


The elbow should be reduced as soon as possible and this is usually accomplished by closed means . Traction is applied with the arm slightly flexed and the olecranon can usu­ally be pushed over the distal humerus. reducing with a definite clunk. Postoperatively the arm is immobilised in a collar and cuff, and mobilisation commenced after one week. Prolonged immobilisation should be avoided as the elbow often becomes stiff.


Instability In most cases the elbow is stable after reduction but occasionally there is a tendency for the elbow to redislocate in extension. In these circumstances, after reduction, the elbow is managed in a cast brace preventing full extension initially. The extension block can be gradually reduced over 2-3 weeks. Late instability is rarely a problem after simple dislocation and is more usually associated with complex fracture dislocations.
Stiffness some loss of extension is not uncommon after elbow dislocation but rarely a functional problem unless the arm has been immobilized for long periods


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