**3.1. Superficial dissection**

The surgeon should begin by palpating the bony landmarks around the shoulder, including the acromion, the clavicle, and the coracoid process. An 8–10-cm incision should be marked out, extending from the lateral margin of the coracoid process and extending down the deltopectoral groove toward the deltoid tuberosity. A scalpel should be used to carry the incision through the skin and the dermal layer. Electrocautery can then be used to address any bleeding in the subcutaneous layer. Dissection can continue through the subcutaneous tissue until the fascia overlying the deltoid and the pectoralis muscles is reached. At this point, careful dissection should be used to identify the interval between these muscles. The cephalic vein may be visualized running in the deltopectoral groove. If it is not evident, often times, a stripe of fat overlying the cephalic vein may be identified and used as a helpful marker for identifying the interval (**Figure 2**). The vein should be freed from the surrounding structures and retracted either medially or laterally, depending on surgeon preference. An anatomic study was performed on 40 cadaveric specimens with latex injection of the cephalic vein.

**Figure 2.** Deltopectoral interval as demarcated by the stripe of fat overlying the cephalic vein. The pectoralis major is identified by the \*, while the deltoid is marked by the +.

subscapularis have been described: a tenotomy [19], peeling the tendon off the lesser tuberosity [18], or an osteotomy of the lesser tuberosity [22]. Each of the methods will be described and compared in this chapter. The methods for repair for each of these procedures will be

**Figure 3.** After splitting the deltopectoral interval, the conjoint tendon of the coracobrachialis and the short head of the

Surgical Approaches in Shoulder Arthroplasty http://dx.doi.org/10.5772/intechopen.70363 67

biceps can be visualized, marked by the \*. The pectoralis major tendon is marked with an X.

When preparing to tenotomize the subscapularis tendon, it is important to identify the superior and inferior borders of the tendon. The arm should be held in adduction and external rotation as it tensions the subscapularis tendon and moves the tenotomy site further away from the axillary nerve. The tenotomy should be made approximately 1 cm medial to the subscapularis insertion on the lesser tuberosity of the humerus. This is typically the location of the anatomic neck of the humerus. It is important to leave a small cuff of subscapularis tendon on the lesser tuberosity to which to repair the tendon during closure. In addition, when releasing the inferior portion of the subscapularis, it is necessary to identify and cauterize the anterior humeral circumflex artery and the two accompanying veins in order to prevent retraction and subsequent bleeding. When performing the tenotomy, it can be helpful to place two large-caliber, braided sutures in the medial aspect of the tendon in order to hold tension during the tenotomy and to help during repair of the tenotomy. When performing a tenotomy for shoulder arthroplasty, the tenotomy and subsequent capsulotomy may be performed simultaneously by releasing the deeper tissues and continuing the dissection along the neck of the humerus. If this method is chosen, it is very important to place a blunt retractor between your dissection and the axillary nerve, coursing inferior to the glenoid, in order to prevent iatrogenic injury (**Figure 4**). Alternatively, the subscapularis may be released

described in the closure section.

*3.2.1. Subscapularis tenotomy*

The authors found more branches from the cephalic vein on the deltoid side, allowing them to conclude that lateral retraction may be more efficacious in preventing bleeding [20]. Once the vein has been retracted, blunt dissection can be used to identify the undersurface of both muscle bellies. A kobel retractor can then be used with one blade under each muscle belly, allowing exposure of the clavipectoral fascia and conjoined tendons of the short head of the biceps and the coracobrachialis (**Figure 3**). Once the fascia is divided in line with the incision, it is pivotal to identify the axillary nerve as it courses near the inferior border of the subscapularis tendon. The surgeon should gently palpate medially over the musculotendinous junction and feel for the axillary nerve. Once found, the nerve should be protected with retractors through the duration of the case. The nerve will then travel posteriorly as it passes inferior to the glenoid where it exits the quadrangular space along with the posterior circumflex humeral vessels. A kobel retractor should be utilized to retract the conjoined tendon medially, exposing the subscapularis tendon over the anterior aspect of the glenohumeral joint. Care must be taken to avoid excessive retraction of the conjoined tendon to avoid a neuropraxia of the musculocutaneous nerve [21].

#### **3.2. Handling of the subscapularis**

In order to access the glenohumeral joint capsule, the subscapularis tendon must be mobilized and retracted from the operative field. In the literature, three methods for releasing the

**Figure 3.** After splitting the deltopectoral interval, the conjoint tendon of the coracobrachialis and the short head of the biceps can be visualized, marked by the \*. The pectoralis major tendon is marked with an X.

subscapularis have been described: a tenotomy [19], peeling the tendon off the lesser tuberosity [18], or an osteotomy of the lesser tuberosity [22]. Each of the methods will be described and compared in this chapter. The methods for repair for each of these procedures will be described in the closure section.

#### *3.2.1. Subscapularis tenotomy*

The authors found more branches from the cephalic vein on the deltoid side, allowing them to conclude that lateral retraction may be more efficacious in preventing bleeding [20]. Once the vein has been retracted, blunt dissection can be used to identify the undersurface of both muscle bellies. A kobel retractor can then be used with one blade under each muscle belly, allowing exposure of the clavipectoral fascia and conjoined tendons of the short head of the biceps and the coracobrachialis (**Figure 3**). Once the fascia is divided in line with the incision, it is pivotal to identify the axillary nerve as it courses near the inferior border of the subscapularis tendon. The surgeon should gently palpate medially over the musculotendinous junction and feel for the axillary nerve. Once found, the nerve should be protected with retractors through the duration of the case. The nerve will then travel posteriorly as it passes inferior to the glenoid where it exits the quadrangular space along with the posterior circumflex humeral vessels. A kobel retractor should be utilized to retract the conjoined tendon medially, exposing the subscapularis tendon over the anterior aspect of the glenohumeral joint. Care must be taken to avoid excessive retraction of the conjoined tendon to avoid a neuropraxia of

**Figure 2.** Deltopectoral interval as demarcated by the stripe of fat overlying the cephalic vein. The pectoralis major is

In order to access the glenohumeral joint capsule, the subscapularis tendon must be mobilized and retracted from the operative field. In the literature, three methods for releasing the

the musculocutaneous nerve [21].

identified by the \*, while the deltoid is marked by the +.

66 Advances in Shoulder Surgery

**3.2. Handling of the subscapularis**

When preparing to tenotomize the subscapularis tendon, it is important to identify the superior and inferior borders of the tendon. The arm should be held in adduction and external rotation as it tensions the subscapularis tendon and moves the tenotomy site further away from the axillary nerve. The tenotomy should be made approximately 1 cm medial to the subscapularis insertion on the lesser tuberosity of the humerus. This is typically the location of the anatomic neck of the humerus. It is important to leave a small cuff of subscapularis tendon on the lesser tuberosity to which to repair the tendon during closure. In addition, when releasing the inferior portion of the subscapularis, it is necessary to identify and cauterize the anterior humeral circumflex artery and the two accompanying veins in order to prevent retraction and subsequent bleeding. When performing the tenotomy, it can be helpful to place two large-caliber, braided sutures in the medial aspect of the tendon in order to hold tension during the tenotomy and to help during repair of the tenotomy. When performing a tenotomy for shoulder arthroplasty, the tenotomy and subsequent capsulotomy may be performed simultaneously by releasing the deeper tissues and continuing the dissection along the neck of the humerus. If this method is chosen, it is very important to place a blunt retractor between your dissection and the axillary nerve, coursing inferior to the glenoid, in order to prevent iatrogenic injury (**Figure 4**). Alternatively, the subscapularis may be released

the insertion of the subscapularis tendon [26]. In addition, peeling the subscapularis off the humerus will allow for maximal surface area for bony healing to occur. The biggest drawback of this procedure is the need for tendon-to-bone healing to occur in order to maintain subscapularis function, which is, generally, felt to be less reliable than tendon-to-tendon or boneto-bone. However, the literature does vary as there are studies showing excellent healing rates in patients undergoing a subscapularis peel [27]. In addition, the repair requires violating the

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Lastly, the insertion of the subscapularis tendon, the lesser tuberosity, may be osteotomized and retracted without disrupting the tendon itself. Initially, the long head of the biceps tendon can be released and subsequently tenodesed to the upper margin of the pectoralis major tendon. Once the biceps tendon is out of the way, the lesser tuberosity may be visualized in its entirety. The arm should be held in adduction and internal rotation and an osteotome or oscillating saw should be used to perform the osteotomy from the medial aspect of the bicipital groove to the bone-cartilage interface at the anatomic neck. After the lesser tuberosity has been osteomized, freeing the remainder of the subscapularis should proceed as described in the tenotomy section. The lesser tuberosity osteotomy was originally introduced to provide a method of repairing the subscapularis which relied on bone-to-bone healing and did not violate the tendon itself. Healing rates have been shown to be excellent for this method [17, 22]. In addition, medialization of the tendon remains possible with this procedure. The disadvantages of this procedure include difficulty and timeliness of procedure, as well as the potential

There have been several studies in the literature comparing the outcomes, biomechanics, and healing potential of the subscapularis tendon after the above procedures [25, 27–30]. Two cadaver biomechanical studies evaluated the failure rates of the above three methods of repair. One showed improved failure rates for both the subscapularis tenotomy and lesser tuberosity osteotomy [29]. Another showed no significant difference between the three methods [30]. Similarly, a biomechanical study comparing lesser tuberosity osteotomy to tenotomy showed no significant difference in load to failure; however, it did show that the tenotomy group had less displacement during repetitive loading [28]. Clinical comparisons between the groups also have mixed outcomes. A randomized controlled trial comparing subscapularis strength and functional outcomes between lesser tuberosity osteotomy versus subscapularis peel showed no significant difference at 2 years [27]. On the contrary, a retrospective study comparing lesser tuberosity osteotomy versus subscapularis tenotomy at an average of 33 months showed improved clinical outcomes and lower rates of subscapularis tears in the osteotomy group [25]. Because of the large amount of conflicting literature, it is likely that the most important factor regarding handling of the subscapularis is surgeon preference and experience. Great care should be taken to ensure an adequate repair while maintaining appro-

for iatrogenic fracture or nonunion due to violation of the cortical bone.

cortex, thus weakening the proximal humerus.

*3.2.3. Lesser tuberosity osteotomy*

*3.2.4. Comparisons*

priate tendon length.

**Figure 4.** Subscapularis tendon after tenotomy. Note the stay sutures placed in the medial limb of the subscapularis tendon. Also, please note the placement of the Darrach retractor at the inferomedial border of the subscapularis protecting the axillary nerve.

from the anterior capsule prior to arthrotomy, but this method provides less robust tissue for later repair and may lead to subscapularis failure. This approach is the easiest and quickest to perform and repair of all the listed methods. It has been associated with good longterm outcomes [23]. While tendon-to-tendon healing is a reliable means of healing, data in the literature are mixed in regard to maintenance of subscapularis repair with some studies showing excellent healing rates [24] and others showing attenuation or ruptures being common [25]. One disadvantage to this method is the inability to medialize the insertion of the subscapularis tendon or the potential for shortening the tendon during repair causing limits in postoperative external rotation.

#### *3.2.2. Subscapularis peel*

Another method of releasing the subscapularis tendon is the subscapularis peel. Rather than releasing the tendon through a division within the substance of the tendon, the subscapularis is elevated in its entirety off of its insertion on the lesser tuberosity. After the subscapularis has been released from the lesser tuberosity, dissection should proceed as described earlier. The major advantage of the subscapularis peel is that it allows for medialization of the insertion of the subscapularis tendon [26]. In addition, peeling the subscapularis off the humerus will allow for maximal surface area for bony healing to occur. The biggest drawback of this procedure is the need for tendon-to-bone healing to occur in order to maintain subscapularis function, which is, generally, felt to be less reliable than tendon-to-tendon or boneto-bone. However, the literature does vary as there are studies showing excellent healing rates in patients undergoing a subscapularis peel [27]. In addition, the repair requires violating the cortex, thus weakening the proximal humerus.

#### *3.2.3. Lesser tuberosity osteotomy*

Lastly, the insertion of the subscapularis tendon, the lesser tuberosity, may be osteotomized and retracted without disrupting the tendon itself. Initially, the long head of the biceps tendon can be released and subsequently tenodesed to the upper margin of the pectoralis major tendon. Once the biceps tendon is out of the way, the lesser tuberosity may be visualized in its entirety. The arm should be held in adduction and internal rotation and an osteotome or oscillating saw should be used to perform the osteotomy from the medial aspect of the bicipital groove to the bone-cartilage interface at the anatomic neck. After the lesser tuberosity has been osteomized, freeing the remainder of the subscapularis should proceed as described in the tenotomy section. The lesser tuberosity osteotomy was originally introduced to provide a method of repairing the subscapularis which relied on bone-to-bone healing and did not violate the tendon itself. Healing rates have been shown to be excellent for this method [17, 22]. In addition, medialization of the tendon remains possible with this procedure. The disadvantages of this procedure include difficulty and timeliness of procedure, as well as the potential for iatrogenic fracture or nonunion due to violation of the cortical bone.

#### *3.2.4. Comparisons*

from the anterior capsule prior to arthrotomy, but this method provides less robust tissue for later repair and may lead to subscapularis failure. This approach is the easiest and quickest to perform and repair of all the listed methods. It has been associated with good longterm outcomes [23]. While tendon-to-tendon healing is a reliable means of healing, data in the literature are mixed in regard to maintenance of subscapularis repair with some studies showing excellent healing rates [24] and others showing attenuation or ruptures being common [25]. One disadvantage to this method is the inability to medialize the insertion of the subscapularis tendon or the potential for shortening the tendon during repair causing limits

**Figure 4.** Subscapularis tendon after tenotomy. Note the stay sutures placed in the medial limb of the subscapularis tendon. Also, please note the placement of the Darrach retractor at the inferomedial border of the subscapularis

Another method of releasing the subscapularis tendon is the subscapularis peel. Rather than releasing the tendon through a division within the substance of the tendon, the subscapularis is elevated in its entirety off of its insertion on the lesser tuberosity. After the subscapularis has been released from the lesser tuberosity, dissection should proceed as described earlier. The major advantage of the subscapularis peel is that it allows for medialization of

in postoperative external rotation.

*3.2.2. Subscapularis peel*

protecting the axillary nerve.

68 Advances in Shoulder Surgery

There have been several studies in the literature comparing the outcomes, biomechanics, and healing potential of the subscapularis tendon after the above procedures [25, 27–30]. Two cadaver biomechanical studies evaluated the failure rates of the above three methods of repair. One showed improved failure rates for both the subscapularis tenotomy and lesser tuberosity osteotomy [29]. Another showed no significant difference between the three methods [30]. Similarly, a biomechanical study comparing lesser tuberosity osteotomy to tenotomy showed no significant difference in load to failure; however, it did show that the tenotomy group had less displacement during repetitive loading [28]. Clinical comparisons between the groups also have mixed outcomes. A randomized controlled trial comparing subscapularis strength and functional outcomes between lesser tuberosity osteotomy versus subscapularis peel showed no significant difference at 2 years [27]. On the contrary, a retrospective study comparing lesser tuberosity osteotomy versus subscapularis tenotomy at an average of 33 months showed improved clinical outcomes and lower rates of subscapularis tears in the osteotomy group [25]. Because of the large amount of conflicting literature, it is likely that the most important factor regarding handling of the subscapularis is surgeon preference and experience. Great care should be taken to ensure an adequate repair while maintaining appropriate tendon length.

#### **3.3. Humeral exposure**

As stated earlier, when exposing the humerus after a subscapularis tenotomy, the subscapularis tendon and anterior shoulder capsule may be released as a single unit. However, when performing a subscapularis peel or a lesser tuberosity osteotomy, the subscapularis must be separated from the anterior capsule. This may be done by placing a blunt elevator between the two structures and then using a 15 blade to complete the dissection. Once the capsule has been isolated from the subscapularis, a retractor should be placed at the inferior margin of the glenoid to protect the axillary nerve. A capsulotomy may then be performed with sharp dissection or electrocautery extending along the anatomic neck of the humerus, continuing inferior down the humerus. It is important to dissect along the humerus to avoid damaging the nearby neurovascular structures. It is critical to release the capsule off of the neck of the humerus until the latissimus dorsi tendon is visualized as it wraps around the humerus. This provides not only assurance that complete visualization of the anatomic neck of the humerus and accompanying osteophytes is attained but also aids in glenoid visualization. The exposed osteophytes around the humerus should then be removed using a rongeur. Once the humerus has been exposed, a deltoid retractor can be placed posterior to the head to facilitate exposure of the head. The arm should be adducted, extended, and externally rotated in order to dislocate the head and deliver it into the surgical site (**Figure 5**). A Hohmann retractor may be placed on the calcar and a Darrach should be placed medially to protect the soft tissues, specifically the rotator cuff, during the humeral head cut. Depending on the implant system being utilized, an intramedullary or extramedullary cutting guide may be used to help guide your humeral head cut. If performing the cut freehand, the cut should be made along the anatomic neck of the humerus with care taken to avoid violating the supraspinatus insertion on the greater tuberosity. The angle of the cut should match the neck-shaft angle of the implant if the implant is a fixed angle device. Most implants will have a head-neck angle of around 130–140° [31]. After resection, the head should not be removed from the field as it may be useful in deciding implant size and can be used as a source of bone graft if needed. The timing of humeral head resection is typically dictated by surgeon preference and implant system constraints.

the coracoid base. The anterior capsule should then be dissected from the anterior glenoid with great care taken not to violate the subscapularis tendon (**Figure 6**). Care should be taken to avoid releasing the glenoid capsule beyond the 6 o'clock position due to concerns of posterior instability. If the posterior capsule must be released, it should occur on the humeral side.

**Figure 5.** Proximal humeral exposure. The marginal osteophytes have been removed from the subchondral surface using

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At this point, the humerus and glenoid are exposed and ready to be prepared according to the specific methodology for the desired implant being utilized. As a rule, a guide pin is placed at approximately 11–12 mm above the inferior glenoid rim. This allows for ideal placement of the glenoid component and allows for minimization of scapular notching [34]. Hand reamers are then placed over this guide pin to concentrically ream the glenoid. A drill is then utilized to create a slot in the glenoid for which to place the central peg of the glenoid baseplate. If necessary, screws may be placed around the baseplate. Attention is then turned toward the humerus where the intramedullary canal is found. Sequential reamers are introduced into the humeral canal until adequate fit and fill is achieved. The reamer is removed and serial broaches are introduced until the appropriate size is reached. Trial components may be placed at this time to ensure appropriate range of motion with adequate stability. After implantation of the desired components, the shoulder should again be taken through a range

of motion to ensure that the implant is not overstuffed, but also sufficiently stable.

**3.5. Preparation for implantation**

a rongeur. The neck cut should be made along the anatomic neck.

#### **3.4. Glenoid exposure**

After the humeral head has been cut, a Fukuda, or a Bankart, retractor should be placed on the posterior glenoid neck and used to retract the humeral shaft posteriorly and inferiorly, out of the operative field. A double-pronged retractor can be placed on the anterior glenoid neck, and most importantly a Hohmann or a Darrach retractor can be placed along the inferior glenoid neck to protect the axillary nerve at all times during the glenoid preparation. Anatomic studies have shown that the axillary nerve can range from 3 to 7 mm inferior to the musculotendinous junction of the subscapularis muscle [32, 33]. After appropriate retractors have been placed, electrocautery or a sharp 15 blade may be used to circumferentially remove the subscapularis, capsule, and labrum to expose the entire periphery of the glenoid. A 360 release of the subscapularis must be performed in order to adequately expose the glenoid. The inferior capsule must be released, carefully protecting the axillary nerve. The dissection should continue down the humeral shaft to the level of the latissimus dorsi. Afterwards, a pair of curved Mayo scissors may be used to release the rotator interval superiorly. This should extend to the level of

**Figure 5.** Proximal humeral exposure. The marginal osteophytes have been removed from the subchondral surface using a rongeur. The neck cut should be made along the anatomic neck.

the coracoid base. The anterior capsule should then be dissected from the anterior glenoid with great care taken not to violate the subscapularis tendon (**Figure 6**). Care should be taken to avoid releasing the glenoid capsule beyond the 6 o'clock position due to concerns of posterior instability. If the posterior capsule must be released, it should occur on the humeral side.

#### **3.5. Preparation for implantation**

**3.3. Humeral exposure**

70 Advances in Shoulder Surgery

**3.4. Glenoid exposure**

As stated earlier, when exposing the humerus after a subscapularis tenotomy, the subscapularis tendon and anterior shoulder capsule may be released as a single unit. However, when performing a subscapularis peel or a lesser tuberosity osteotomy, the subscapularis must be separated from the anterior capsule. This may be done by placing a blunt elevator between the two structures and then using a 15 blade to complete the dissection. Once the capsule has been isolated from the subscapularis, a retractor should be placed at the inferior margin of the glenoid to protect the axillary nerve. A capsulotomy may then be performed with sharp dissection or electrocautery extending along the anatomic neck of the humerus, continuing inferior down the humerus. It is important to dissect along the humerus to avoid damaging the nearby neurovascular structures. It is critical to release the capsule off of the neck of the humerus until the latissimus dorsi tendon is visualized as it wraps around the humerus. This provides not only assurance that complete visualization of the anatomic neck of the humerus and accompanying osteophytes is attained but also aids in glenoid visualization. The exposed osteophytes around the humerus should then be removed using a rongeur. Once the humerus has been exposed, a deltoid retractor can be placed posterior to the head to facilitate exposure of the head. The arm should be adducted, extended, and externally rotated in order to dislocate the head and deliver it into the surgical site (**Figure 5**). A Hohmann retractor may be placed on the calcar and a Darrach should be placed medially to protect the soft tissues, specifically the rotator cuff, during the humeral head cut. Depending on the implant system being utilized, an intramedullary or extramedullary cutting guide may be used to help guide your humeral head cut. If performing the cut freehand, the cut should be made along the anatomic neck of the humerus with care taken to avoid violating the supraspinatus insertion on the greater tuberosity. The angle of the cut should match the neck-shaft angle of the implant if the implant is a fixed angle device. Most implants will have a head-neck angle of around 130–140° [31]. After resection, the head should not be removed from the field as it may be useful in deciding implant size and can be used as a source of bone graft if needed. The timing of humeral head

resection is typically dictated by surgeon preference and implant system constraints.

After the humeral head has been cut, a Fukuda, or a Bankart, retractor should be placed on the posterior glenoid neck and used to retract the humeral shaft posteriorly and inferiorly, out of the operative field. A double-pronged retractor can be placed on the anterior glenoid neck, and most importantly a Hohmann or a Darrach retractor can be placed along the inferior glenoid neck to protect the axillary nerve at all times during the glenoid preparation. Anatomic studies have shown that the axillary nerve can range from 3 to 7 mm inferior to the musculotendinous junction of the subscapularis muscle [32, 33]. After appropriate retractors have been placed, electrocautery or a sharp 15 blade may be used to circumferentially remove the subscapularis, capsule, and labrum to expose the entire periphery of the glenoid. A 360 release of the subscapularis must be performed in order to adequately expose the glenoid. The inferior capsule must be released, carefully protecting the axillary nerve. The dissection should continue down the humeral shaft to the level of the latissimus dorsi. Afterwards, a pair of curved Mayo scissors may be used to release the rotator interval superiorly. This should extend to the level of At this point, the humerus and glenoid are exposed and ready to be prepared according to the specific methodology for the desired implant being utilized. As a rule, a guide pin is placed at approximately 11–12 mm above the inferior glenoid rim. This allows for ideal placement of the glenoid component and allows for minimization of scapular notching [34]. Hand reamers are then placed over this guide pin to concentrically ream the glenoid. A drill is then utilized to create a slot in the glenoid for which to place the central peg of the glenoid baseplate. If necessary, screws may be placed around the baseplate. Attention is then turned toward the humerus where the intramedullary canal is found. Sequential reamers are introduced into the humeral canal until adequate fit and fill is achieved. The reamer is removed and serial broaches are introduced until the appropriate size is reached. Trial components may be placed at this time to ensure appropriate range of motion with adequate stability. After implantation of the desired components, the shoulder should again be taken through a range of motion to ensure that the implant is not overstuffed, but also sufficiently stable.

After the subscapularis has been securely repaired, the deltopectoral interval may be loosely closed with a running interlocking non-absorbable suture to help identify the interval in future exposure. The subcutaneous layer may be closed in a simple interrupted fashion with either a braided or an unbraided suture depending on surgeon preference. Similarly, the skin may be closed with nylon suture, a running monofilament, staples, or any other acceptable method of skin closure. At this point, a dry dressing or an incisional vacuum should be placed over the wound and the patient should be placed into a sling with an abduction pillow to help

Surgical Approaches in Shoulder Arthroplasty http://dx.doi.org/10.5772/intechopen.70363 73

The deltopectoral approach is the most commonly used approach to the shoulder-for-shoulder arthroplasty. This is in large part due to the many advantages provided by this approach. This approach is an internervous and intermuscular plane, that is, it utilizes the plane between the deltoid and the pectoralis major muscles. This is important as it preserves the origin of the deltoid and the pectoralis and allows for access beyond the muscles while minimizing the risk of denervation. Furthermore, because the approach is between muscles and not splitting the muscles, less bleeding is observed with this approach. Furthermore, should a fracture arise distal to the stem of the humeral component, it is quite easy to extend the deltopectoral approach into the anterolateral approach to the humerus, utilizing the interval between the brachialis and the brachioradialis. Lastly, approaching the glenohumeral joint from the front allows for easier access to the inferior structures, including the inferior humeral osteophytes and the inferior capsule [35]. Positioning of the glenoid component is also easier with this

Though the literature is inconsistent on the matter, many studies have shown that subscapularis-deficient shoulder arthroplasties have higher rates of instability [36, 37]. The deltopectoral approach to the shoulder requires the release of the subscapularis tendon with subsequent repair; however, it is not uncommon for these repairs to fail, leading to a risk of instability in these patients [24, 38]. Furthermore, approaching the glenohumeral joint from the anterior aspect causes difficulty reaching the more posterior structures including the glenoid, capsule, and greater tuberosity. This could be particularly noticeable when performing shoulder arthroplasty for proximal humerus fractures that include a large greater tuberosity fragment. Lynch et al. found that utilizing the deltopectoral approach was an independent

The anterosuperior approach to the shoulder was first described by Mackenzie in 1993 [40]. It does not utilize an internervous plane as it requires detachment of the anterior deltoid off the acromion as well as release of the coracoacromial ligament to reach the glenohumeral joint. Though it was initially designed to provide increased exposure of the glenoid for shoulder

approach as the inferior portion of the glenoid is more readily available.

risk factor for neurologic complications in total shoulder arthroplasty [39].

keep the arm protected.

**3.7. Advantages**

**3.8. Disadvantages**

**4. Anterosuperior approach**

**Figure 6.** Glenoid exposure. Capsular attachments removed circumferentially around the glenoid.

#### **3.6. Closure**

After the components have been appropriately placed and trialed, the wound is ready to be closed. The wound should be irrigated with normal saline. If a significant amount of bleeding was encountered during the surgery, a drain may be placed at this time, if desired. If repairable, the first structure to be repaired is the subscapularis tendon. Depending on how the tendon was released when approaching the shoulder will dictate the method of repair for the tendon. If the subscapularis tenotomy was used, at least three figure-of-eight, largecaliber, braided sutures should be utilized to anatomically repair the tendon. In this particular repair, care should be taken to avoid shortening the tendon as this will result in decreased external rotation function when healed. If the subscapularis was peeled off the lesser tuberosity, the tendon must be repaired using bone tunnels extending from the anatomic neck of the humerus to the lesser tuberosity. Again, heavy, braided, non-absorbable suture should be passed through these drill holes and the subscapularis tendon and tied down in a secure fashion. If the glenohumeral offset was substantially medialized during the procedure, the repair of the insertion of the tendon may be moved more medially to facilitate this. Lastly, if the lesser tuberosity was osteotomized, the surgeon should drill holes in the medial aspect of the bicipital groove. Heavy non-absorbable suture should then be passed around the lesser tuberosity and into the subscapularis tendon. After the lesser tuberosity has been anatomically positioned, it may be secured in place with transosseous sutures. A plate may be placed to augment the repair depending on the preference of the surgeon [26].

After the subscapularis has been securely repaired, the deltopectoral interval may be loosely closed with a running interlocking non-absorbable suture to help identify the interval in future exposure. The subcutaneous layer may be closed in a simple interrupted fashion with either a braided or an unbraided suture depending on surgeon preference. Similarly, the skin may be closed with nylon suture, a running monofilament, staples, or any other acceptable method of skin closure. At this point, a dry dressing or an incisional vacuum should be placed over the wound and the patient should be placed into a sling with an abduction pillow to help keep the arm protected.

### **3.7. Advantages**

The deltopectoral approach is the most commonly used approach to the shoulder-for-shoulder arthroplasty. This is in large part due to the many advantages provided by this approach. This approach is an internervous and intermuscular plane, that is, it utilizes the plane between the deltoid and the pectoralis major muscles. This is important as it preserves the origin of the deltoid and the pectoralis and allows for access beyond the muscles while minimizing the risk of denervation. Furthermore, because the approach is between muscles and not splitting the muscles, less bleeding is observed with this approach. Furthermore, should a fracture arise distal to the stem of the humeral component, it is quite easy to extend the deltopectoral approach into the anterolateral approach to the humerus, utilizing the interval between the brachialis and the brachioradialis. Lastly, approaching the glenohumeral joint from the front allows for easier access to the inferior structures, including the inferior humeral osteophytes and the inferior capsule [35]. Positioning of the glenoid component is also easier with this approach as the inferior portion of the glenoid is more readily available.

#### **3.8. Disadvantages**

**3.6. Closure**

72 Advances in Shoulder Surgery

After the components have been appropriately placed and trialed, the wound is ready to be closed. The wound should be irrigated with normal saline. If a significant amount of bleeding was encountered during the surgery, a drain may be placed at this time, if desired. If repairable, the first structure to be repaired is the subscapularis tendon. Depending on how the tendon was released when approaching the shoulder will dictate the method of repair for the tendon. If the subscapularis tenotomy was used, at least three figure-of-eight, largecaliber, braided sutures should be utilized to anatomically repair the tendon. In this particular repair, care should be taken to avoid shortening the tendon as this will result in decreased external rotation function when healed. If the subscapularis was peeled off the lesser tuberosity, the tendon must be repaired using bone tunnels extending from the anatomic neck of the humerus to the lesser tuberosity. Again, heavy, braided, non-absorbable suture should be passed through these drill holes and the subscapularis tendon and tied down in a secure fashion. If the glenohumeral offset was substantially medialized during the procedure, the repair of the insertion of the tendon may be moved more medially to facilitate this. Lastly, if the lesser tuberosity was osteotomized, the surgeon should drill holes in the medial aspect of the bicipital groove. Heavy non-absorbable suture should then be passed around the lesser tuberosity and into the subscapularis tendon. After the lesser tuberosity has been anatomically positioned, it may be secured in place with transosseous sutures. A plate may be placed

**Figure 6.** Glenoid exposure. Capsular attachments removed circumferentially around the glenoid.

to augment the repair depending on the preference of the surgeon [26].

Though the literature is inconsistent on the matter, many studies have shown that subscapularis-deficient shoulder arthroplasties have higher rates of instability [36, 37]. The deltopectoral approach to the shoulder requires the release of the subscapularis tendon with subsequent repair; however, it is not uncommon for these repairs to fail, leading to a risk of instability in these patients [24, 38]. Furthermore, approaching the glenohumeral joint from the anterior aspect causes difficulty reaching the more posterior structures including the glenoid, capsule, and greater tuberosity. This could be particularly noticeable when performing shoulder arthroplasty for proximal humerus fractures that include a large greater tuberosity fragment. Lynch et al. found that utilizing the deltopectoral approach was an independent risk factor for neurologic complications in total shoulder arthroplasty [39].
