Three and four part FracturesThree-Part FracturesThree part fractures involve displacement of one of the tuberosities and the humeral shaft. The attached tuberosity exerts a rotational deforming force, making it difficult to control the articular segment. When the greater tuberosity is displaced, the intact lesser tuberosity internally rotates the articular segment. When the lesser tuberosity is displaced (a much less common pattern), the intact greater tuberosity externally rotates and abducts the articular segment. Neer reported high rates of nonunion and malunion in patients treated with closed reduction. These fractures require surgical stabilization if the patient is medically stable. TreatmentThe choice of fixation is based on:
In young patients with good bone quality, internal fixation is preferred. In elderly, low demand
patients with osteoporotic bone, prosthetic replacement should be considered.
The use of plates requires more extensive soft tissue stripping, which may increase the risk of osteonecrosis. Resch et al described closed reduction and percutaneous pinning of displaced three and four part fractures. Percutaneous reduction and pin fixation - technique Several designs of proximal humeral locking plates exist, thought to have an improved hold in osteoporotic bone. Non absorbable suture alone has been used, however if metaphyseal comminution is present, this technique can be augmented with modified Ender nails. New locking proximal intramedullary nails have also been designed to
allow reconstruction of the proximal humerus onto the nail, including locking
screws and suture of the cuff.
Four-Part FracturesAlthough the number of studies comparing nonoperative treatment with hemiarthroplasty in the treatment of displaced three- and four-part proximal humerus fractures is small, the results of nonoperative treatment are considered to be inferior. Nonoperative treatment of displaced three-and four-part fractures is recommended only when patients are medically unfit to undergo surgery (e.g., patients who are at higher risk for medical complications due to comorbid conditions involving cardiac, pulmonary, renal, or other organ systems). The preferred treatment of four-part fractures is humeral head replacement, primarily because of the high risk of osteonecrosis and secondarily because of the difficulty in obtaining secure internal fixation. In young patients with good quality bone one may still consider open reduction and internal fixation as even in the presence of radiological osteonecrosis patients can have relatively good shoulder function. The exception is the valgus-impacted
four-part fracture pattern for which limited open reduction and internal
fixation have provides satisfactory outcomes. When performing proximal humeral prosthetic replacement, several principles must be followed:
Hemiarthroplasty for trauma - surgical technique
Valgus-Impacted FracturesIn 1991, Jakob et al emphasized the anatomic features of the four-part valgus-impacted fracture of the proximal humerus.
The valgus impacted four-part fracture is characterized by impaction of the
lateral aspect of the humeral articular surface through a fracture of the
anatomic neck. This lateral impaction results in a valgus deformity
of the humeral head such that the articular surface faces superiorly, toward the acromion, rather than medially, toward the glenoid. As the articular surface is
imploded into the proximal humeral metaphysis, the greater and lesser
tuberosities typically displace from each other as well as from the humeral
shaft through intertubercular and surgical neck fractures lines.
The lack of displacement between the medial aspect of the humeral articular surface and the shaft preserves the inferomedial part of the periosteum and its associated vessels. Therefore, the prevalence of necrosis of the humeral head (5% to 10%) is much lower than that associated with standard four-part fractures. Moreover, the continuous sleeve of tissue connecting the shaft, tuberosities, glenohumeral joint capsule, and rotator cuff imparts substantial stability and encourages anatomical or nearly anatomical reduction of the tuberosities when the head is reduced .
Radiographic Features - (Valgus impacted 4 part)Initial radiographs should include an anteroposterior view in the scapular plane, a lateral scapular view (Y view), and an axillary view. At first glance, the severity of valgus impacted four-part fractures may be underestimated. Close inspection reveals the humeral articular surface to be facing superiorly. The displacement of the greater and lesser tuberosities (especially the greater tuberosity) may seem severe, but the relative tuberosity displacement is primarily the result of the valgus impaction of the humeral head. The intertubercular fracture line is typically posterior to the bicipital groove. This is an important consideration when operative reduction is being contemplated.
Treatment Options of Valgus impacted four part fracture
The vast majority of valgus impacted four-part fractures are amenable to percutaneous reduction and internal fixation. Nonoperative treatment often results in painful malunion and therefore is indicated only for elderly, sedentary patients with medical comorbidities that preclude operative treatment. Percutaneous reduction and internal fixation is an excellent option for patients who have an acute injury (seven to ten days old), good bone quality, and minimal comminution and can be relied on to cooperate with treatment. Percutaneous Reduction and Internal Fixation valgus impacted four part - technique
Open reduction and internal fixation is primarily indicated for acute fractures that are not reducible by closed means, for severe osteopoenic bone, for extensive comminution, or for fractures that are between ten days and four months old.
Hemiarthroplasty is reserved for fractures that are more than four months old or the rare acute fracture in an elderly, sedentary patient with severe osteopoenia. Hemiarthroplasty for trauma - technique
Fracture-DislocationsThese complex injuries require a reduction maneuver to restore the position of the humeral head in the glenoid. With two-part tuberosity fracture-dislocations, closed reduction often reduces the tuberosity into an acceptable position. Two-part surgical neck fracture-dislocations are less common and often require open reduction and internal fixation. Three-part fracture-dislocations require open reduction and internal fixation, and four-part fracture-dislocations are typically managed with prosthetic replacement.
Complications of three and four part fracturesNeurovascular.The close proximity of the brachial plexus to the glenohumeral joint increases the risk of associated neurologic injury. With an incidence as high as 6.2%. The axillary nerve is most commonly involved by virtue of its position as it passes inferior to the subscapularis muscle and wraps around the surgical neck of the humerus. Furthermore, the axillary nerve can be injured during percutaneous pinning or when utilizing a deltoid-splitting approach. Burkhead showed that the position of the axillary nerve averages 6.2 cm from the mid-acromion in male patients and 5.4 cm in female patients. The musculocutaneous nerve must also be
protected during the deltopectoral approach. This nerve enters the
coracobrachialis 3.1 to 8.2 cm distal to the coracoid. Retraction of the
conjoined tendon muscles can lead to musculocutaneous nerve injury. The axillary artery is the most often injured at a site proximal to the anterior circumflex artery. Clues to arterial injury are:
REMEMBER, the presence of distal pulses does not exclude an arterial injury proximally. If there is concern about an arterial injury, an angiogram should be considered, and a vascular surgery consult should be obtained.
Stenning et al highlighted the problems of diagnosis and treatment of arterial injury at the shoulder following low-energy injuries. Osteonecrosis.Incidence:
It has been reported that even in the presence of radiological osteonecrosis patients may still have surprisingly good shoulder function.
Malunion.Malunion can occur as a result of initial acceptance of unacceptable alignment, loss of acceptable initial alignment secondary to inadequate immobilization, aggressive early physical therapy, loss of closed reduction, or failure to achieve or maintain adequate reduction following surgical stabilization. Varus malunion can lead to loss of abduction and subacromial impingement. Apex anterior angulation can limit forward elevation. Malunion of the greater tuberosity, either superiorly or posteriorly, can lead to subacromial impingement or impingement of the tuberosity on the posterior glenoid, both of which will result in significant loss of motion.
Nonunion.Nonunions of the proximal humerus are not very common; however, when they do occur, it is most commonly following surgical neck fractures. Risk factors include:
Open Reduction and internal fixation
Use of isolated vertical fixation, such as with Rush pins, was associated with failure to hold the tuberosities, proximal migration of the rods, and impingement problems. Wire-loop fixation and cuff repair provided more consistent stabilization for three-part fractures. Four-part fractures treated by open reduction consistently failed, most commonly secondary to osteonecrosis. This led Neer to recommend open reduction and internal fixation for three-part fractures and prosthetic arthroplasty for displaced four-part fractures. The use of vertical fixation alone
with non locking intramedullary rods is inadequate for these fractures
and is no longer recommended. Less favourable results occurred in
elderly patients with poor bone quality and in patients with
fracture-dislocations. Koval et al found plate-and-screw fixation to be the most biomechanically stable. The weakest techniques involved the use of only a
tension band with either wire or nonabsorbable suture. In one study, use of a
tension band alone led to a 27% rate of loss of fixation. Precise surgical technique is
critical for a good result, as reported failures were due to impingement that
resulted from proximal positioning of the plate. A modified cloverleaf plate was used for fixation. All fractures healed, and there were no cases of osteonecrosis. The average age of patients was 55 years, and all had good bone quality. The author attributed the successful results to two factors: patient selection (young age and good bone quality) and surgical technique (limited exposure, careful soft-tissue dissection, use of small cancellous screws, and placement of the plate high on the head without impingement). The author concluded that open
reduction and internal fixation should be the initial treatment of displaced
three- and four-part proximal humerus fractures, and that primary prosthetic
replacement should be reserved for four-part fractures in elderly patients with
osteopenic bones and for any patient with poor bone quality. Most fractures were the result of high-energy trauma.
HemiarthroplastyIndicationsThe relative indications for hemiarthroplasty in the management of displaced three- and four-part proximal humerus fractures have evolved from a careful analysis of the results of open reduction and internal fixation of these injuries. The fixation of fracture fragments in osteoporotic bone can often be quite tenuous. Therefore, elderly patients with displaced fractures and poor bone quality are the primary candidates for hemiarthroplasty.
At issue is the premise that late hemiarthroplasty will remain a viable salvage option should the primary treatment of the displaced three- or four-part proximal humerus fracture fail.
However, several investigators have noted that revision to hemiarthroplasty is:
A number of other variables may affect the ultimate outcome after treatment of proximal humerus fractures with hemiarthroplasty:
Other independent investigators observed findings similar to those of Neer with regard to consistent pain relief after hemiarthroplasty, but less dramatic gains in range of motion were demonstrated. Factors contributing to a favourable result include:
Some of these factors are interrelated. Older patients with more limited activity levels may be less inclined to continue with a prolonged and rigorous rehabilitation program. Patients who have sustained three-part fractures also possess an intact tuberosity, which may be precisely osteotomized to preserve bone and thus permit
improved tuberosity healing.
TechniqueSee Shoulder hemiarthroplasty for trauma - technique ComplicationsAcute reconstruction appears to be associated with complications related primarily to surgical technique. Causes for failure
In contrast, late prosthetic reconstruction appears to be associated with complications related to scarring and distortion of anatomy after initial attempts at open reduction and internal fixation. In several studies directly comparing the complications of acute and late reconstruction, late reconstruction was more difficult because of poor rotator cuff quality, resulting in secondary shoulder instability or subluxation. Difficulty with exposure and lack of normal anatomic landmarks in these reconstructions further contribute to such complications as nerve palsy and humeral fracture.
SummaryThree- and four-part proximal humeral fractures are difficult injuries to evaluate and treat. Preoperative and intraoperative evaluation must address fracture pattern, bone quality, patient motivation, and expectations. Four-part valgus-impacted fractures may be treated with minimal dissection and osteosynthesis. In non–valgus-impacted fractures, age and bone quality will determine subsequent management. Patients who are physiologically young and have good bone quality will benefit from attempts to preserve the native anatomy with open reduction and internal fixation. Patients who are elderly and have poor bone quality are better treated with early hemiarthroplasty. Those who are medically unable to undergo the rigors of surgery or rehabilitation may be treated nonoperatively. Postoperative complications are minimized by a carefully supervised rehabilitation program and early reconstruction.
References
IANNOTTI, JOSEPH P. MD, PHD; RAMSEY, MATTHEW L. MD; WILLIAMS, GERALD R. MD; WARNER, JON J.P. MD NONPROSTHETIC MANAGEMENT OF PROXIMAL HUMERAL FRACTURES. Journal of Bone & Joint Surgery - American Volume. 85-A(8):1578-1593, August 2003.
RP Jakob, A Miniaci, PS Anson, H Jaberg, A Osterwalder, and R Ganz; Four-part valgus impacted fractures of the proximal humerus; J Bone Joint Surg Br, Mar 1991; 73-B: 295 - 298.
H. Resch, P. Povacz, R. Fröhlich, and M. Wambacher; PERCUTANEOUS FIXATION OF THREE- AND FOUR-PART FRACTURES OF THE PROXIMAL HUMERUS; J Bone Joint Surg Br, Mar 1997; 79-B: 295 - 300
Zyto K, Ahrengart L, Sperber A, Tornkvist H; Treatment of displaced proximal humeral fractures in elderly patients; J Bone Joint Surg Br. 1997 May;79(3):412-7.
Page created by: Lee Van RensburgLast updated: 11/09/2015
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