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Four-Part Fractures of the Proximal Humerus: Open Reduction and Internal Fixation versus Hemiarthroplasty
Four-Part Fractures of the Proximal Humerus: Open Reduction and Internal Fixation versus Hemiarthroplasty Andrew D. Bries, MD,* and Robert H. Bell, MD*,† One of the more challenging issues in upper extremity surgery is the four-part proximal humeral fracture. Humeral fractures of this variety carry a higher risk of avascular necrosis and associated worse prognosis than many others. Despite this risk, this fracture in younger patients is best treated with internal fixation and restoration of anatomic alignment. The valgus impacted fracture often lends itself toward better outcomes with open reduction and internal fixation. In contrast, the displaced four-part proximal humeral fracture and/or dislocation, more frequently seen in the elderly, is best treated with humeral head replacement, which more predictably results in a pain-free shoulder and acceptable range of motion. Semin Arthro 19:45-49 © 2008 Elsevier Inc. All rights reserved. KEYWORDS proximal humerus, ORIF, shoulder, four-part fracture, hemiarthroplasty
T
he incidence of fractures of the proximal humerus has continued to increase as our population ages. This aging population is also staying much more active into their later days, requiring us to no longer accept the results of older treatment methods that result in lower functional outcomes. In addition, new types of fixation and repair (ie, reverse total shoulder, proximal humerus locking plates, etc) have also presented us with more options for treatment and subsequently more outcomes. Presented here is a systematic approach to management of the complex four-part proximal humerus fracture.
Classification The Neer classification of proximal humerus fractures has become the favored system over the years based on its simplicity of description of a fracture by parts.1 The Neer system does not address comminution but deals specifically with the greater tuberosity, lesser tuberosity, head fragment, and shaft. Each fragment becomes a part when it exhibits greater than 1 cm of displacement or greater than 45° of angulation.1 While this system has been used osten*Department of Orthopedics, Summa Health System, Akron, OH. †Crystal Clinic, Akron, OH. Address reprint requests to Andrew Bries, MD, Summa Health System, Department of Orthopedics, 444 North Main Street, Akron, OH 44310. E-mail: [email protected]
1045-4527/08/$-see front matter © 2008 Elsevier Inc. All rights reserved. doi:10.1053/j.sart.2007.12.029
sibly with regard to judging appropriate treatment and prognosis, difficulties with inter- and intraobserver reliability have limited its utility. The key to understanding four-part proximal humeral fractures is the displacement specifically of the head fragment best defined in routine radiographic studies.
Radiographic Evaluation When evaluating a proximal humerus fracture a standard shoulder trauma series should be obtained. The trauma series consists of three views: true anteroposterior (AP), lateral scapular, and axillary. In those rare instances in which pain precludes obtaining an axillary view, a Velpeau axillary may be obtained more readily. When examining these specific views, the AP view gives a good appreciation of varus or valgus inclination of the head fragment relative to the glenoid and the status of the greater tuberosity in terms of superior displacement and compromise of the subacromial space. It does not, however, give good understanding for posterior displacement. The lateral scapular view better defines the posterior displacement of the greater and lesser tuberosities and also the position of the head relative to the glenoid fossa. The axillary view is optimal for determining displacement of the head relative to the glenoid and associated subluxation or dislocation and provides the surgeon with an idea of comminution 45
46 and involvement of the articular surface. Computed tomography scans, with the use of standard axial cuts or three-dimensional reconstructions, can be very helpful to define overall comminution, joint surface involvement, and tuberosity displacement. All of the earlier mentioned criteria are critical in deciding on hemiarthroplasty versus open reduction internal fixation (ORIF).
Nonoperative Treatment As is the case with all musculoskeletal injuries, there is a role for nonoperative management. Individuals who do not do well with postoperative restrictions include those who have compromised mental status resulting in an inability to cooperate with postoperative rehabilitation or those who have compromised functional status requiring the use of wheelchair with preinjury difficulty with transfers. We must also consider nonoperative management in those with significant medical comorbidities.2,3
Open Reduction Internal Fixation There are several situations in which ORIF should be first line of treatment for four-part proximal humerus fractures. First and foremost is when the head fragment is likely to remain vascular, such as in a young patient with a four-part fracture or the valgus impacted four-part fracture. In both instances vascularity is likely to be preserved and the risk of avascular necrosis diminished.4-13 Hertel and coworkers7 described metaphyseal extension, intact medial hinge, and basic fracture pattern as the best predictors of intact blood supply, thus aiding the surgeon with radiographic criteria to predict vascularity of the head.8,12 Furthermore, ORIF should be considered when one is certain to establish a stable construct that will allow early restoration of motion and recreation of normal joint congruity. For this to occur the surgeon must be familiar with the technique and the fixation systems’ advantages and limitations. To that end, in patients in whom there is severe osteoporosis and a history of prior fracture nonunion, the preferable and more appropriate treatment would be a primary hemiarthroplasty, not ORIF.
A. Bries and R. Bell have significant head impaction and/or head splitting, articular surface compromise, likely avascular head, or small nonfixable fragments, a hemiarthroplasty is the optimal means of fixation. The valgus impacted four-part fracture was first described by Jakob and coworkers15 in 1991 in a series of 19 patients, 14 of whom were treated with ORIF. The 5 patients who were treated with nonsurgical intervention obtained statistically poorer results and, in those individuals in whom ORIF had been performed instead of a humeral head replacement, the avascular necrosis rate was substantially lower than had been reported in the literature previously. The authors concluded this was due to sparing of the posterior medial vessels supplying blood to the head, which had been preserved in this somewhat unique fracture. Further studies by Resch and coworkers9 and Vandenbussche and coworkers13 found similarly low rates of avascular necrosis, further reinforcing this concept of ORIF in valgus impacted four-part fractures. The concept of preserved blood supply in the valgus impacted type has been reinforced in additional later studies.7,8,12 Given this information, the current recommendation for valgus impacted injuries is anterior lateral deltoid split, elevation of the head fragment, application of allograft to maintain head height, bringing the lesser and greater tuberosity back under the head fragment to maintain alignment followed by internal fixation.4,6,10,11
When To Do a Hemiarthroplasty Those individuals who are best suited for hemiarthroplasty in four-part proximal humeral fractures are older patients in excess of 65 years of age, those individuals with significantly compromised bone quality in which fixation will be an issue, patients with marked head displacement and/or dislocation, fractures in which there is comminution of the articular surface, and patients in whom an anatomic reconstruction is
Do It Right the First Time The literature has shown mixed results throughout the years regarding the surgical treatment of proximal humerus fractures. In 1995, Norris and coworkers14 looked at hemi-arthroplasties performed for failed three- and four-part fractures treated with either primary ORIF or nonoperative management. They found that delayed hemiarthroplasty had results inferior to primary hemiarthroplasty and concluded that humeral head replacement should be performed in all four-part fractures and in some three-part fractures with associated severe osteopenia, fracture comminution, and other significant comorbidities.2,3,14 Therefore, in individuals who
Figure 1 Suture placement interlacing tuberosities and implant prior to fixation. (Color version of figure is available online.)
Fractures of the proximal humerus
47
attempted but fails and at the same setting a hemiarthroplasty may be performed.16,17 One should remember that performing a hemiarthroplasty when the fixation falls apart has been shown by Norris and coworkers14 in 1995 and several authors since then to be a viable option but one with worse results than with primary hemiarthroplasty.18,19
Technical Aspects of Performing a Hemiarthroplasty Two keys to the performance of a hemiarthroplasty for fourpart proximal humeral fractures are tuberosity repair and component positioning. Numerous authors have addressed the issues of tuberosity nonunion and malunion, noting a high correlation between failure in hemiarthroplasties for four-part fractures and tuberosity problems.20-24 To that end, there are three key points for handling of tuberosities in hemiarthroplasty: 1) tuberosity fixation begins with heavy suture material that incorporates tendon as well as bone to prevent pull out (Fig 1). 2) Autogenous bone graft is be placed beneath the tuberosities and the modular head to enhance union rate. 3) An integrated suture system incorporating stable fixation of the tuberosities, shaft, and prosthesis is used. Critical to this suture construct is the use of circum-
Figure 2 Final placement of sutures incorporating tuberosities and circumferential circlage. (Color version of figure is available online.)
Figure 3 Use of version rod to check rotation relative to forearm and bicipital groove as viewed anteriorly. (Color version of figure is available online.)
ferential sutures to decrease tuberosity motion and to enhance healing23 (Fig 2). Humeral component positioning in four-part fractures has always been a challenging task. Numerous devices have been created to facilitate this, including external and internal jigs, all of which are somewhat cumbersome. The system employed by the senior author uses a jigless device that allows insertion of the trial humeral component, expansion of the tip of the prosthesis, and, once appropriate version and head height are determined, locking it in place. The modular head trial is then placed on the humeral stem, the shoulder is reduced, and the tuberosities are reduced beneath the head to assess rotator cuff tension and position of the head relative to the glenoid. Having assured correct trial position, the height and version of the trial are recorded and those measurements are transposed to the true, final humeral stem before cementation. The loss of metaphyseal bone in this fracture necessitates placing the humeral component in a somewhat “proud” position, recreating the normal anatomic neck height. Version is determined by reference to the bicipital groove. While not an absolute measure of version, placing the lateral fin of the trial humeral stem 7 to 10 mm posterior to the bicipital groove at the time of trial reduction will provide a reasonable amount of retroversion. After reduction, with tuberosities reduced, the optimal version can then be better determined and changes made (Figs 3 and 4). As one would imagine, head size should attempt to duplicate the resected head so as to facilitate tuberosity placement.
A. Bries and R. Bell
48
Figure 4 Use of version rod to check rotation relative to forearm and bicipital groove as viewed from above. To give the prosthesis 30° of retroversion the forearm should be externally rotated while the implant is in neutral. (Color version of figure is available online.)
Summary The treatment of four-part fractures of the proximal humerus is never simple and often the surgeon is faced with a number of treatment options, including ORIF and hemiarthroplasty. In most cases the following rules will be helpful: ●
●
● ●
Four-part fracture– dislocations in the elderly over the age of 60 years do best with primary humeral head replacement. In patients under 50 years primary ORIF should be attempted; however, if anatomic reduction of the joint surface is unattainable, primary humeral head replacement should be undertaken. Valgus impacted fractures are best treated with ORIF and bone grafting. Avascular necrosis does not always result in a poor outcome and often mirrors the outcome of primary arthroplasty if anatomic reduction is obtained.
5.
6.
7.
8.
9.
10.
11. 12.
References 1. Neer CS 2nd: Displaced proximal humeral fractures I. Classification and evaluation. J Bone Joint Surg Am 52:1077-1089, 1970 2. Olsson CA, Nordquist, Petersson CJ: Long-term outcome of a proximal humerus fracture predicted after 1 year: A 13-year prospective populationbased follow-up study of 47 patients. Acta Orthop 76:397-402, 2005 3. Olsson C, Petersson CJ: Clinical importance of comorbidity in patients with a proximal humerus fracture. Clin Orthop Relat Res 442:93-99, 2006 4. Atalar AC, Demirhan M, Uysal M, et al: Treatment of Neer type 4 impacted valgus fractures of the proximal humerus with open reduc-
13.
14.
15. 16.
tion, elevation, and grafting. Acta Orthop Traumatol Turc 41:113-119, 2007 Court-Brown CM, Cattermole H, McQueen MM: Impacted valgus fractures (B1.1) of the proximal humerus: The results of nonoperative treatment. J Bone Joint Surg Br 84:504-508, 2002 DeFranco MJ, Brems JJ, Williams GR JR, et al: Evaluation and management of valgus impacted four-part proximal humerus fractures. Clin Orthop Relat Res 442:109-114, 2006 Hertel R, Hempfing A, Stiehler M, et al: Predictors of humeral head ischemia after intracapsular fracture of the proximal humerus. J Shoulder Elbow Surg 13:427-433, 2004 Panagopoulos AM, Dimakopoulos P, Tyllianakis M, et al: Valgus impacted proximal humeral fractures and their blood supply after transosseous suturing. Int Orthop 28:333-337, 2004 Resch H, Povacz P, Fröhlich R, et al: Percutaneous fixation of three- and four-part fractures of the proximal humerus. J Bone Joint Surg Br 79: 295-300, 1997 Robinson CM, Page RS: Severely impacted valgus proximal humeral fractures: Results of operative treatment. J Bone Joint Surg Am 85: 1647-1655, 2003 Robinson CM, Page RS: Severely impacted valgus proximal humeral fractures. J Bone Joint Surg Am 86:143-155, 2004 (suppl) Sanchez-Sotelo J: Proximal humerus fractures. Clin Anat 19:588-598, 2006 Vandenbussche E, Peraldi P, Naouri JF, et al: Four part valgus impacted fractures of the upper extremity of humerus: Ilium graft reconstruction. Apropos of 8 cases. Rev Chir Orthop 82:658-662, 1996 Norris TR, Green A, McGuigan FX: Late prosthetic shoulder arthroplasty for displaced proximal humerus fractures. J Shoulder Elbow Surg 4:271-280, 1995 Jakob RP, Miniaci A, Anson PS, et al: Four-part valgus impacted fractures of the proximal humerus. J Bone Joint Surg Br 73:295-298, 1991 Ko JY, Yamamoto R: Surgical treatment of complex fracture of the proximal humerus. Clin Orthop Relat Res 327:225-237, 1996
Fractures of the proximal humerus 17. Mighell MA, Kolm GP, Collinge CA, et al: Outcomes of hemiarthroplasty for fractures of the proximal humerus. J Shoulder Elbow Surg 12:569-577, 2003 18. Bosch U, Skutek M, Fremerey RW, et al: Outcome after primary and secondary hemiarthroplasty in elderly patients with fractures of the proximal humerus. J Shoulder Elbow Surg 7:479-484, 1998 19. Gobel F, Wuthe T, Reichel H: Results of shoulder hemiarthroplasty in patients with acute and old fractures of the proximal humerus. Z Orthop Ihre Grenzgeb 137:25-30, 1999 20. Boileau P, Krishnan SG, Tinsi L, et al: Tuberosity malposition and migration: Reasons for poor outcomes after hemiarthroplasty for displaced fractures of the proximal humerus. J Shoulder Elbow Surg 11:401-412, 2002
49 21. Frankle MA, Greenwald DP, Markee BA, et al: Biomechanical effects of malposition of tuberosity fragments on the humeral prosthetic reconstruction for four-part proximal humerus fractures. J Shoulder Elbow Surg 10:321-326, 2001 22. Frankle MA, Mighell MA: Techniques and principles of tuberosity fixation for proximal humeral fractures treated with hemiarthroplasty. J Shoulder Elbow Surg 13:239-247, 2004 23. Frankle MA, Ondrovic LE, Markee BA, et al: Stability of tuberosity reattachment in proximal humeral hemiarthroplasty. J Shoulder Elbow Surg 11:413-420, 2002 24. Loebenberg MI, Jones DA, Zuckerman JD: The effect of greater tuberosity placement on active range of motion after hemiarthroplasty for acute fractures of the proximal humerus. Bull Hosp Joint Dis 62:90-93, 2005
T
he incidence of fractures of the proximal humerus has continued to increase as our population ages. This aging population is also staying much more active into their later days, requiring us to no longer accept the results of older treatment methods that result in lower functional outcomes. In addition, new types of fixation and repair (ie, reverse total shoulder, proximal humerus locking plates, etc) have also presented us with more options for treatment and subsequently more outcomes. Presented here is a systematic approach to management of the complex four-part proximal humerus fracture.
Classification The Neer classification of proximal humerus fractures has become the favored system over the years based on its simplicity of description of a fracture by parts.1 The Neer system does not address comminution but deals specifically with the greater tuberosity, lesser tuberosity, head fragment, and shaft. Each fragment becomes a part when it exhibits greater than 1 cm of displacement or greater than 45° of angulation.1 While this system has been used osten*Department of Orthopedics, Summa Health System, Akron, OH. †Crystal Clinic, Akron, OH. Address reprint requests to Andrew Bries, MD, Summa Health System, Department of Orthopedics, 444 North Main Street, Akron, OH 44310. E-mail: [email protected]
1045-4527/08/$-see front matter © 2008 Elsevier Inc. All rights reserved. doi:10.1053/j.sart.2007.12.029
sibly with regard to judging appropriate treatment and prognosis, difficulties with inter- and intraobserver reliability have limited its utility. The key to understanding four-part proximal humeral fractures is the displacement specifically of the head fragment best defined in routine radiographic studies.
Radiographic Evaluation When evaluating a proximal humerus fracture a standard shoulder trauma series should be obtained. The trauma series consists of three views: true anteroposterior (AP), lateral scapular, and axillary. In those rare instances in which pain precludes obtaining an axillary view, a Velpeau axillary may be obtained more readily. When examining these specific views, the AP view gives a good appreciation of varus or valgus inclination of the head fragment relative to the glenoid and the status of the greater tuberosity in terms of superior displacement and compromise of the subacromial space. It does not, however, give good understanding for posterior displacement. The lateral scapular view better defines the posterior displacement of the greater and lesser tuberosities and also the position of the head relative to the glenoid fossa. The axillary view is optimal for determining displacement of the head relative to the glenoid and associated subluxation or dislocation and provides the surgeon with an idea of comminution 45
46 and involvement of the articular surface. Computed tomography scans, with the use of standard axial cuts or three-dimensional reconstructions, can be very helpful to define overall comminution, joint surface involvement, and tuberosity displacement. All of the earlier mentioned criteria are critical in deciding on hemiarthroplasty versus open reduction internal fixation (ORIF).
Nonoperative Treatment As is the case with all musculoskeletal injuries, there is a role for nonoperative management. Individuals who do not do well with postoperative restrictions include those who have compromised mental status resulting in an inability to cooperate with postoperative rehabilitation or those who have compromised functional status requiring the use of wheelchair with preinjury difficulty with transfers. We must also consider nonoperative management in those with significant medical comorbidities.2,3
Open Reduction Internal Fixation There are several situations in which ORIF should be first line of treatment for four-part proximal humerus fractures. First and foremost is when the head fragment is likely to remain vascular, such as in a young patient with a four-part fracture or the valgus impacted four-part fracture. In both instances vascularity is likely to be preserved and the risk of avascular necrosis diminished.4-13 Hertel and coworkers7 described metaphyseal extension, intact medial hinge, and basic fracture pattern as the best predictors of intact blood supply, thus aiding the surgeon with radiographic criteria to predict vascularity of the head.8,12 Furthermore, ORIF should be considered when one is certain to establish a stable construct that will allow early restoration of motion and recreation of normal joint congruity. For this to occur the surgeon must be familiar with the technique and the fixation systems’ advantages and limitations. To that end, in patients in whom there is severe osteoporosis and a history of prior fracture nonunion, the preferable and more appropriate treatment would be a primary hemiarthroplasty, not ORIF.
A. Bries and R. Bell have significant head impaction and/or head splitting, articular surface compromise, likely avascular head, or small nonfixable fragments, a hemiarthroplasty is the optimal means of fixation. The valgus impacted four-part fracture was first described by Jakob and coworkers15 in 1991 in a series of 19 patients, 14 of whom were treated with ORIF. The 5 patients who were treated with nonsurgical intervention obtained statistically poorer results and, in those individuals in whom ORIF had been performed instead of a humeral head replacement, the avascular necrosis rate was substantially lower than had been reported in the literature previously. The authors concluded this was due to sparing of the posterior medial vessels supplying blood to the head, which had been preserved in this somewhat unique fracture. Further studies by Resch and coworkers9 and Vandenbussche and coworkers13 found similarly low rates of avascular necrosis, further reinforcing this concept of ORIF in valgus impacted four-part fractures. The concept of preserved blood supply in the valgus impacted type has been reinforced in additional later studies.7,8,12 Given this information, the current recommendation for valgus impacted injuries is anterior lateral deltoid split, elevation of the head fragment, application of allograft to maintain head height, bringing the lesser and greater tuberosity back under the head fragment to maintain alignment followed by internal fixation.4,6,10,11
When To Do a Hemiarthroplasty Those individuals who are best suited for hemiarthroplasty in four-part proximal humeral fractures are older patients in excess of 65 years of age, those individuals with significantly compromised bone quality in which fixation will be an issue, patients with marked head displacement and/or dislocation, fractures in which there is comminution of the articular surface, and patients in whom an anatomic reconstruction is
Do It Right the First Time The literature has shown mixed results throughout the years regarding the surgical treatment of proximal humerus fractures. In 1995, Norris and coworkers14 looked at hemi-arthroplasties performed for failed three- and four-part fractures treated with either primary ORIF or nonoperative management. They found that delayed hemiarthroplasty had results inferior to primary hemiarthroplasty and concluded that humeral head replacement should be performed in all four-part fractures and in some three-part fractures with associated severe osteopenia, fracture comminution, and other significant comorbidities.2,3,14 Therefore, in individuals who
Figure 1 Suture placement interlacing tuberosities and implant prior to fixation. (Color version of figure is available online.)
Fractures of the proximal humerus
47
attempted but fails and at the same setting a hemiarthroplasty may be performed.16,17 One should remember that performing a hemiarthroplasty when the fixation falls apart has been shown by Norris and coworkers14 in 1995 and several authors since then to be a viable option but one with worse results than with primary hemiarthroplasty.18,19
Technical Aspects of Performing a Hemiarthroplasty Two keys to the performance of a hemiarthroplasty for fourpart proximal humeral fractures are tuberosity repair and component positioning. Numerous authors have addressed the issues of tuberosity nonunion and malunion, noting a high correlation between failure in hemiarthroplasties for four-part fractures and tuberosity problems.20-24 To that end, there are three key points for handling of tuberosities in hemiarthroplasty: 1) tuberosity fixation begins with heavy suture material that incorporates tendon as well as bone to prevent pull out (Fig 1). 2) Autogenous bone graft is be placed beneath the tuberosities and the modular head to enhance union rate. 3) An integrated suture system incorporating stable fixation of the tuberosities, shaft, and prosthesis is used. Critical to this suture construct is the use of circum-
Figure 2 Final placement of sutures incorporating tuberosities and circumferential circlage. (Color version of figure is available online.)
Figure 3 Use of version rod to check rotation relative to forearm and bicipital groove as viewed anteriorly. (Color version of figure is available online.)
ferential sutures to decrease tuberosity motion and to enhance healing23 (Fig 2). Humeral component positioning in four-part fractures has always been a challenging task. Numerous devices have been created to facilitate this, including external and internal jigs, all of which are somewhat cumbersome. The system employed by the senior author uses a jigless device that allows insertion of the trial humeral component, expansion of the tip of the prosthesis, and, once appropriate version and head height are determined, locking it in place. The modular head trial is then placed on the humeral stem, the shoulder is reduced, and the tuberosities are reduced beneath the head to assess rotator cuff tension and position of the head relative to the glenoid. Having assured correct trial position, the height and version of the trial are recorded and those measurements are transposed to the true, final humeral stem before cementation. The loss of metaphyseal bone in this fracture necessitates placing the humeral component in a somewhat “proud” position, recreating the normal anatomic neck height. Version is determined by reference to the bicipital groove. While not an absolute measure of version, placing the lateral fin of the trial humeral stem 7 to 10 mm posterior to the bicipital groove at the time of trial reduction will provide a reasonable amount of retroversion. After reduction, with tuberosities reduced, the optimal version can then be better determined and changes made (Figs 3 and 4). As one would imagine, head size should attempt to duplicate the resected head so as to facilitate tuberosity placement.
A. Bries and R. Bell
48
Figure 4 Use of version rod to check rotation relative to forearm and bicipital groove as viewed from above. To give the prosthesis 30° of retroversion the forearm should be externally rotated while the implant is in neutral. (Color version of figure is available online.)
Summary The treatment of four-part fractures of the proximal humerus is never simple and often the surgeon is faced with a number of treatment options, including ORIF and hemiarthroplasty. In most cases the following rules will be helpful: ●
●
● ●
Four-part fracture– dislocations in the elderly over the age of 60 years do best with primary humeral head replacement. In patients under 50 years primary ORIF should be attempted; however, if anatomic reduction of the joint surface is unattainable, primary humeral head replacement should be undertaken. Valgus impacted fractures are best treated with ORIF and bone grafting. Avascular necrosis does not always result in a poor outcome and often mirrors the outcome of primary arthroplasty if anatomic reduction is obtained.
5.
6.
7.
8.
9.
10.
11. 12.
References 1. Neer CS 2nd: Displaced proximal humeral fractures I. Classification and evaluation. J Bone Joint Surg Am 52:1077-1089, 1970 2. Olsson CA, Nordquist, Petersson CJ: Long-term outcome of a proximal humerus fracture predicted after 1 year: A 13-year prospective populationbased follow-up study of 47 patients. Acta Orthop 76:397-402, 2005 3. Olsson C, Petersson CJ: Clinical importance of comorbidity in patients with a proximal humerus fracture. Clin Orthop Relat Res 442:93-99, 2006 4. Atalar AC, Demirhan M, Uysal M, et al: Treatment of Neer type 4 impacted valgus fractures of the proximal humerus with open reduc-
13.
14.
15. 16.
tion, elevation, and grafting. Acta Orthop Traumatol Turc 41:113-119, 2007 Court-Brown CM, Cattermole H, McQueen MM: Impacted valgus fractures (B1.1) of the proximal humerus: The results of nonoperative treatment. J Bone Joint Surg Br 84:504-508, 2002 DeFranco MJ, Brems JJ, Williams GR JR, et al: Evaluation and management of valgus impacted four-part proximal humerus fractures. Clin Orthop Relat Res 442:109-114, 2006 Hertel R, Hempfing A, Stiehler M, et al: Predictors of humeral head ischemia after intracapsular fracture of the proximal humerus. J Shoulder Elbow Surg 13:427-433, 2004 Panagopoulos AM, Dimakopoulos P, Tyllianakis M, et al: Valgus impacted proximal humeral fractures and their blood supply after transosseous suturing. Int Orthop 28:333-337, 2004 Resch H, Povacz P, Fröhlich R, et al: Percutaneous fixation of three- and four-part fractures of the proximal humerus. J Bone Joint Surg Br 79: 295-300, 1997 Robinson CM, Page RS: Severely impacted valgus proximal humeral fractures: Results of operative treatment. J Bone Joint Surg Am 85: 1647-1655, 2003 Robinson CM, Page RS: Severely impacted valgus proximal humeral fractures. J Bone Joint Surg Am 86:143-155, 2004 (suppl) Sanchez-Sotelo J: Proximal humerus fractures. Clin Anat 19:588-598, 2006 Vandenbussche E, Peraldi P, Naouri JF, et al: Four part valgus impacted fractures of the upper extremity of humerus: Ilium graft reconstruction. Apropos of 8 cases. Rev Chir Orthop 82:658-662, 1996 Norris TR, Green A, McGuigan FX: Late prosthetic shoulder arthroplasty for displaced proximal humerus fractures. J Shoulder Elbow Surg 4:271-280, 1995 Jakob RP, Miniaci A, Anson PS, et al: Four-part valgus impacted fractures of the proximal humerus. J Bone Joint Surg Br 73:295-298, 1991 Ko JY, Yamamoto R: Surgical treatment of complex fracture of the proximal humerus. Clin Orthop Relat Res 327:225-237, 1996
Fractures of the proximal humerus 17. Mighell MA, Kolm GP, Collinge CA, et al: Outcomes of hemiarthroplasty for fractures of the proximal humerus. J Shoulder Elbow Surg 12:569-577, 2003 18. Bosch U, Skutek M, Fremerey RW, et al: Outcome after primary and secondary hemiarthroplasty in elderly patients with fractures of the proximal humerus. J Shoulder Elbow Surg 7:479-484, 1998 19. Gobel F, Wuthe T, Reichel H: Results of shoulder hemiarthroplasty in patients with acute and old fractures of the proximal humerus. Z Orthop Ihre Grenzgeb 137:25-30, 1999 20. Boileau P, Krishnan SG, Tinsi L, et al: Tuberosity malposition and migration: Reasons for poor outcomes after hemiarthroplasty for displaced fractures of the proximal humerus. J Shoulder Elbow Surg 11:401-412, 2002
49 21. Frankle MA, Greenwald DP, Markee BA, et al: Biomechanical effects of malposition of tuberosity fragments on the humeral prosthetic reconstruction for four-part proximal humerus fractures. J Shoulder Elbow Surg 10:321-326, 2001 22. Frankle MA, Mighell MA: Techniques and principles of tuberosity fixation for proximal humeral fractures treated with hemiarthroplasty. J Shoulder Elbow Surg 13:239-247, 2004 23. Frankle MA, Ondrovic LE, Markee BA, et al: Stability of tuberosity reattachment in proximal humeral hemiarthroplasty. J Shoulder Elbow Surg 11:413-420, 2002 24. Loebenberg MI, Jones DA, Zuckerman JD: The effect of greater tuberosity placement on active range of motion after hemiarthroplasty for acute fractures of the proximal humerus. Bull Hosp Joint Dis 62:90-93, 2005