Anatomy of the humeral bone
it is a long bone in the arm which connected the shoulder joint to elbow joint and run from scapula to the bone of the forearm (radius and ulna) the humeral bone consists of upper end which consists of rounded head and narrow neck and two short process called greater and lesser tuberosities which constriction below it called surgical neck which it is common site for
fractures and it is body or shaft which it is cylindrical in it is upper part and more prismatic below and lower end which consists of two epicondyles lateral and medial epicondyles and two process trochlea and capitulum and three fossa which are radial fossa coronoid fossa olecranon fossa

Fractures of humerus can be divided into fractures of proximal humerus fractures of distal humerus and fractures of humeral shaft and avulsion fractures of greater tuberosity
Proximal humeral fractures

Fractures of the proximal metaphysis of the humerus are one of the most common fractures in the elderly, with a dramatic increase in incidence after the age of 60 years. They account for approximately 5-7% of adult fractures and are most common in elderly females and generally occur from a fall on an outstretched hand they occur less common in young adults but are often more serious with associated injuries such as shoulder dislocation because of the higher force requried to fracture non osteoporotic bone patients presents with pain swelling and tenderness about the shoulder and have difficulty with active motion three orthogonal radiographic views of the shoulder best demonstrate the displacement of the fracture these consist of an anteroposterior view a scapular Y view and axillary view the location of fracture can be categorized as anatomic neck , surgical neck greater tuberosity and lesser tuberosity displacement of the fracture fragments can be explained by the muscular force that are applied to them in surgical neck fractures the shaft tends to displace anteromedially because of the pull of the pectoralis major greater tuberosity fractures are displaced superiorly and posteriorly by attached supraspinatus , infrasupinatus and teres minor lesser tuberosity fragments are displaced medially by the subscapularis

Proximal humeral fractures were classified by Neer in 1970 and this is still an accepted classification.and most commonly used and is subdivided by the number of displaced fracture fragments A two -part fracture is any fracture with one major fragment displaced from the remainder of the humerus similarly three- and four -part fractures describe fractures with two and three displaced major fragments respectively displacement required reduction is defined as that which is greater than 1 cm or has angulation of more than 45 degree Minimally displaced fractures are treated with immobilization followed by early range of motion The more severe injuries consist of four main parts: the shaft, the articular surface, together with separate, displaced greater and lesser tuberosities

Treatment of these injuries is dependent on the severity and displacement of the fractures. In the majority of cases fractures are minimally displaced and treated conservatively with good results expected. Immobilisation in a sling for 2-3 weeks is recom­mended. Displaced fractures, particularly in the younger patient, are treated by internal fixation with a plate and screws, multiple pins or an intramedullary device; again good results can be anti­cipated.

The treatment of four-part fractures in the elderly osteoporotic patient is still unresolved owing to the unsatisfactory results with all methods of treatment. Conservative treatment can result in a stiff painful shoulder but operative treatment often results in the same outcome. A number of methods of fixation have been described including plates and screws, multiple wires, tension band wiring and intramedullary devices. Insecure fixation in the osteoporotic bone, together with difficulties in reattaching the tuberosities and subsequent rotator cuff problems, will produce poor results. Primary replacement of the humeral head, with a metal prosthesis, is frequently performed and was originally rec­ommended by Neer for severe injuries. Unfortunately hemiarthroplasty is also
frequently complicated by stiffness or rotator cuff problem
Summary of Treatment of proximal humeral fractures
minimally displaced fractures can be treated non operatively . displaced fractures in the young adult need internal fixation . four part fractures in the elderly have a poor result whether the shoulder is replaced the fractures are fixed or they are treated non operatively
Avulsion of the greater tuberosity

This fracture is included in the classification described by Neer but should also be considered separately.The injury is often asso­ciated with dislocation of the glenohumeral joint and represents a rotator cuff injury. The fracture may appear to be minimally dis­placed after reduction of the dislocation.  
Avulsion frafures of the greater tuberosity
• Undisplaced fractures need careful observation

• Displaced fractures need reducing and filing

Malunion produces greater impingement problems

Displaced fractures should be anatomically fixed with screws through a lateral approach. Undisplaced fractures may be treated conservatively but regular review, initially with weekly radi­ographs, is required. Malunited fractures will lead to impingement symptoms which do not respond as well to later decompression.
Humeral shaft fractures

These injuries account for approximately 3% of adult fractures and are most common in patients in their 70 years, usually as a result of a simple fall; approximately 80% of the patients are female. A second, slightly smaller peak in incidence occurs in patients in their 20 years . In this group 80% of the patients are male and the injury is due to a road traffic accident or sport. In the majority of cases humeral shaft fractures are closed injuries, with open frac­tures and associated injuries being more common in the younger age group.

The majority of humeral fractures can be treated conservatively, particularly in the elderly, with good return of function antici­pated. A sling or splintage is employed for 2-3 weeks, at which time mobilisation can be commenced. Hanging casts have been recommended, but can result in distraction of the fracture site and increased risk of non-union.
 Operative treatment is indicated in patients with open fractures, associated vascular injuries and particularly in patients with mul­tiple injuries. Open reduction and plate fixation is the most com­mon method of stabilization although intramedullary nailing from either a proximal or distal entry points is frequently used external fixation is occasionally indicated for associated severe soft tissue problem

Non-union Up to 10% of humeral fractures will be complicated by non-union, particularly transverse fractures of the midshaft of the bone. Treatment is usually internal fixation and bone grafting of the non-union site with subsequent healing in most cases.
Nerve palsy Radial nerve palsy can also occur in up to 10% of patients, with a wrist drop and loss of extension of the fingers  . The majority will recover and therefore the injury is treated conservatively, With the patient managed with physiother­apy and a radial nerve splint. Up to 10% of these patients will have no recovery of function and may require exploration of the nerve at about 3 months after the injury. Early exploration is indi­cated if the nerve is initially Intact but dysfunction occurs after closed or open management.
Distal humeral fractures

These are the least common of the metaphyseal fractures of the upper limb, and commonly require internal fixation and early mobilisation to produce good results. As with clavicle fractures, the injury is more common in young males and is usually due to moderate to severe trauma. In the elderly distal humeral fractures are more common In females and again are usually due to mild or moderate trauma.
Anatomy and classification of fractures

The elbow consists of a medial and lateral column, with an articular surface at the distal end. The trochlea at the end of the medial column articulates with the ulna and contributes to flexion and extension at the elbow. The capitellum, the articular sur­face of the lateral column. articulates with the radial head and contributes to pronation and supination at the elbow.

Anatomically the fractures may involve the medial or the lateral column In isolation, with separation of the condyle from the rest of the humerus. These are relatively uncommon, accounting for only 5% of elbow fractures In adults. The more complex injures involve both columns. with complete separation of the arucular surface from the diaphysis, together with a fracture through the articular surface. It is these T- or Yshaped fractures that can be particularly difficult to treat.

Minimally displaced fractures can be treated conservatively With plintage followed by gentle mobilisation as comfort allows. In adults immobilsation of the elbow for longer than 2-3 weeks should be avoided as softness and functional restriction can occur. This is particularly true for complex injures, or following opera­tive management of the fractures.
For displaced fracture internal fixation is recommended for all age groups; stable fixation with plates and/or screws should be used to allow early mobilisation, Single column fractures can usu­ally be stabilised through a limited approach but the complex T­ or Y fracture require a wide exposure of the joint to ensure accu­rate reduction, and usually two plates are necessary for stable fix­ation to the humeral shaft. In order to gain the necessary access, osteotomy of the ulna is usually required and these injuries require surgical skill and experience to achieve good results.

In the elderly osteoporotic patient, especially with very distal fractures, stable internal fixation is not possible. In these patients primary elbow replacement has been carried out with good results . This avoids the need for an osteotomy, with its risk of non-union and implant problems, and allows immediate mobil­isation of the elbow.
• Minimally displaced, can be treated non operatively

• Displaced intra-artitular fracture - in the young need internal fixation- in the elderly osteoporotic patient may need immediate replacement


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