hngtcdsooattatp

oagaofwbt

Glenoid Exposure: Tricks of the TradeTodd C. Moen, MD, and Louis U. Bigliani, MD

Achieving sufficient exposure of the glenoid is one of the most demanding aspects ofshoulder arthroplasty surgery. Beginning with the positioning of patient and ending with thefinal placement and adjustment of retractors, multiple maneuvers must be taken at eachstep of the procedure to ultimately allow for adequate glenoid visualization. With thoughtfulplanning, patience, and attention to detail, the glenoid can be reliably and reproduciblyexposed to allow for a successful reconstruction. This article outlines the key technicalsteps and pearls for successful glenoid exposure.Semin Arthro 22:17-20 © 2011 Elsevier Inc. All rights reserved.

KEYWORDS shoulder, arthroplasty, glenoid, surgical technique

t

paman(

qmssstau

is4err

Achieving sufficient exposure of the glenoid is one of themost demanding aspects of shoulder arthroplasty. When

ealthy and unaffected by degenerative joint disease, the gle-oid is small, buried deep in the musculature of the shoulderirdle, and difficult to visualize. In an osteoarthritic shoulder,he scale of these obstacles is amplified, making an already-hallenging endeavor even more so. Because of its inherentifficulty, exposure of the glenoid should be seen less as aingle step in a reconstruction procedure and more as anngoing process that begins the moment a patient enters theperating room. Beginning with the positioning of the patientnd ending with the final placement and adjustment of re-ractors, multiple maneuvers must be taken at each step ofhe procedure to ultimately allow for adequate glenoid visu-lization. With thoughtful planning, patience, and attentiono detail, the glenoid can be reliably and reproducibly ex-osed to allow a successful implantation and reconstruction.The disease process of osteoarthritis distorts the anatomy

f the native glenoid to varying degrees; as the result of theselterations, it is imperative to obtain proper imaging of thelenohumeral joint to evaluate the abnormal anatomy andid in preoperative planning. The native glenoid is typicallyriented in neutral version to slight retroversion. When af-ected by osteoarthritis, the glenoid is subjected to posteriorear, resulting in an increase in retroversion and net loss ofone (Fig. 1). Varying studies report differing degrees, buthe increase in retroversion in an osteoarthritic shoulder is

The Center for Shoulder, Elbow and Sports Medicine, New York Orthopae-dic Hospital, Columbia University, College of Physicians and Surgeons,New York, NY.

Address reprint requests to Louis U. Bigliani, MD, Chairman, Department ofOrthopaedic Surgery, Columbia University, Medical Cent, 622 West

w168th Street, PH 11, New York, NY 10032. E-mail: lub1@columbia.edu

1045-4527/11/$-see front matter © 2011 Elsevier Inc. All rights reserved.doi:10.1053/j.sart.2011.01.005

ypically 10-15°.1-5 The amount and location of bone loss canvary on the basis of the native anatomy, but the most severebone loss is characteristically posterior. Appropriate imagingis critical to forming a preoperative plan. The radiographicevaluation begins with a standard trauma series of AP,Grashey, scapular Y, and axillary views, with particular atten-tion being paid to the axillary views for assessment of glenoidversion and bone stock. However, multiple authors have rec-ommended a preoperative computed tomography (CT) scanto assess the glenoid,1,3,5 and this has become the standard

rotocol at our institution. A CT scan allows a more precisenalysis of the glenoid vault and thus provides a helpful roadap during glenoid preparation and implantation, as well as

n accurate measure of glenoid bone stock and the possibleeed for glenoid bone grafting during the reconstructionFig. 1).

As mentioned previously in this article, achieving an ade-uate exposure of the glenoid should be kept perpetually inind during a shoulder arthroplasty procedure, as multiple

teps during throughout the case can cumulatively add up toufficient visualization. A full and complete description of theurgical exposure and technique for a shoulder reconstruc-ion is beyond the scope of this work. Rather, it is mostppropriate to highlight the specific steps and pearls that canltimately aid in optimal exposure.Adequate glenoid exposure begins with patient position-

ng. The patient is positioned in a modified beach chair po-ition, with the head of the bed elevated approximately 30-5°. The patient is placed at the edge of the bed to allow thentire arm to be fully extended. Optimal glenoid exposureequires that the arm be extended, abducted, and externallyotated; only if the patient is positioned at the edge of the bed

ill this positioning of the arm be possible. Two surgical

17

18 T.C. Moen and L.U. Bigliani

towels are placed at the medial border of the scapula to pre-vent migration of the entire scapula medially, which in turncauses the glenoid to a more posterior orientation. The entireupper extremity is sterilely prepped and draped to the level ofthe medial clavicle.

A standard deltopectoral approach is used, and specificsteps are worth noting that can aid in the optimization ofglenoid exposure. A 10- to 12-cm incision is made startingfrom 1 cm distal to the clavicle, just lateral to the coracoid,directed toward the deltoid insertion. Some authors wouldadvocate the use of a smaller incision. However, a smallerincision can require vigorous retraction of the soft tissues,and possibly result in a tension neuropraxia in some cases6-8;therefore, we err towards a marginally longer incision to op-timize exposure and minimize the need for excessive retrac-tion. The skin is initially incised with a #10 blade, but all

Figure 1 Axial CT image showing retroversion of the glenoid andposterior glenoid bone loss because of osteoarthritis.

Figure 2 Intraoperative photo of a right shoulder. Preparing for thesubdeltoid release. The anterior edge of the CA ligament is graspedwith an Adson forceps. The leading edge of the CA ligament isexcised with electrocautery, and the plane between the acromion

and deltoid undersurface and rotator cuff is developed.

subsequent dissection is performed with needle-tip electro-cautery, and care is taken to maintain meticulous hemostasis.A dry surgical field is critical to obtain and maintain adequatevisualization throughout the case.

Once the deltopectoral interval has been identified andentered, dissection continues to the level of the clavicopec-toral fascia. At this point, the superior edge of the pectoralismajor insertion is taken down from the humerus, to be re-paired at the end of the case. Releasing the pectoralis allowsthe humerus to be more easily manipulated into the optimalposition of extension, abduction, and external rotation whenthe time comes for final glenoid exposure, and the morbidityof this release is minimal. After release of the pectoralis, theclavicopectoral fascia is incised just laterally to the conjoinedtendon and strap muscles, and carried proximally to the levelof the coracoacromial (CA) ligament. Taking care not to in-jure the musculocutaneous nerve, one should release anyadhesions under the conjoined tendon. Next, a subdeltoidrelease is performed by releasing the anterior edge of the CAligament, with continuation laterally to open the plane be-tween the acromion and deltoid undersurface and the rotatorcuff. To accomplish this, the midportion of the CA ligamentis grasped with an Adson forceps at the anterior edge of theCA ligament (Fig. 2). A semilunar cut is made in the CAligament from medial to lateral, and a portion of the ligamentis excised. At the lateral edge of the ligament, an elevator canbe used to bluntly free the rotator cuff and humerus from thedeltoid undersurface and acromion, and any subacromialbursal tissue or adhesions can be excised sharply, if neces-sary. This step serves 2 purposes. First, partial resection ofthe CA ligament provides improved visualization of the su-

Figure 3 Intraoperative photo of a right shoulder. Subscapularistenotomy. The superior edge of the subscapularis has been released1 cm medial to its insertion on the lesser tuberosity. Tag sutureshave been placed, and the subscapularis is slowly dissected off thehumerus.

perior glenoid while preserving part of the CA arch. Second,

tsabbo4pfccnT6sapcdwttstrf

smtwpibgtap

eaomaccamlnhooha

bes

Glenoid exposure 19

the subdeltoid release allows the humerus to be retractedsufficiently posteriorly for final glenoid exposure.

At this point in the procedure, release and mobilize thesubscapularis in a circumferential fashion to enter the gleno-humeral joint. Some authors argue that a lesser tuberosityosteotomy can enhance exposure9-11; however, we believehat a subscapularis tenotomy also provides excellent expo-ure. To perform the tenotomy, begin by cauterrizing thenterior humeral circumflex artery and veins at the inferiororder of the subscapularis. The tenotomy is then performed,eginning the cut 1 cm medial to the subscapularis insertionn the lesser tuberosity; the tendon edge is then tagged with#2 nonabsorbable braided nylon sutures (Fig. 3). At this

oint, a 360-degree subscapularis release must be per-ormed. To accomplish this, begin with a thorough inferiorapsular release with needlepoint electrocautery. During theapsular release, care must be taken to protect the axillaryerve, which is in close proximity to the area of dissection.he capsule is slowly taken down off the humeral shaft to the-o’clock position. To protect the nerve, the arm is progres-ively externally rotated as the capsule is released; addition-lly, a metal finger retractor or a narrow Darrach retractor islaced around the neck, protecting the nerve. The inferiorapsular release should continue to the level of the latissimusorsi insertion. Superiorly, the rotator interval is releasedith Mayo scissors, freeing the subscapularis all the way to

he level of the base of the coracoid. The anterior capsule ishen dissected out and removed from the undersurface of theubscapularis. The plane between the subscapularis and an-erior capsule is most readily identified at the muscular infe-ior border. The capsule is carefully dissected and excisedrom the inside-out, taking great care not to violate the sub-

Figure 4 Intraoperative photo of a left shoulder. A large anteroinfe-rior osteophyte is being excised with an osteotome to enhance ex-

rposure.

capularis muscle and tendon. The capsulectomy proceedsedially, freeing the capsule and subscapularis from the an-

erior glenoid. The anterior labrum is carefully excised asell. The glenoid capsule is not released past the 6-o’clockosition, the inferior midpoint, as this may lead to posterior

nstability. If the posterior capsule needs to be released, it cane done from the humeral side, which requires removal of thelenoid retractors and palpation of the capsule on the neck ofhe humerus. A full 360° release is absolutely necessary tollow the required posterior translation and retraction to ex-ose the glenoid.Proper preparation of the humerus is critical to achieving

xposure of the glenoid. The key principles of humeral prep-ration as it relates to glenoid exposure are adequate removalf humeral osteophytes, and adequate resection of the hu-eral head with the humeral cut. It is critical to remove all

nterior and inferior osteophytes, as this allows for identifi-ation of the true anatomic neck of the humerus (Fig. 4). It isritical to identify the true anatomic neck, as this allows for anccurate humeral head resection. The humeral head cut,ade in the appropriate version, should exit at the supero-

ateral aspect of the humerus, within 5 mm of the supraspi-atus insertion on the greater tuberosity. After the humeralead cut has been made, previously inaccessible posteriorsteophytes can then be removed. It is critical to remove allsteophytes and resect the appropriate amount of femoralead. Excess humeral osteophytes or bone can impair visu-lization of the glenoid.

After all soft-tissue releases and humeral resections haveeen performed, the final placement of retractors is nec-ssary to expose the glenoid. Specific retractors are neces-ary for adequate exposure. A Fukuda retractor is used to

Figure 5 Intraoperative photo of a right shoulder. Final placement ofretractors, displaying adequate exposure of the glenoid.

etract the humerus posteriorly; alternatively, a malleable

20 T.C. Moen and L.U. Bigliani

retractor or even a narrow Darrach retractor can be used inplace of the Fukuda. Anteriorly, place a special spike Dar-rach retractor (Fig. 5). Given the proximity of the axillarynerve and the spike on the retractor, this retractor must beplaced with caution. At this point, the glenoid is exposedand ready to be prepared for whatever reconstruction isindicated.

The timeless surgical adage that one cannot fix what onecannot see is particularly true regarding the glenoid in shoul-der arthroplasty. Adequate exposure of the glenoid is criticalto allowing a surgeon to perform a successful and durablereconstruction. The aforementioned steps as well as an atten-tion to detail throughout the case are helpful in achievingoptimal exposure and visualization, in turn allowing a suc-cessful reconstruction.

References1. Friedman RJ, Hawthorne KB, Genez BM: The use of computerized

tomography in the measurement of glenoid version. J Bone Joint SurgAm 74:1032-1037, 1992

2. Scalise JJ, Bryan J, Polster J, et al: Quantitative analysis of glenoid boneloss in osteoarthritis using three-dimensional computed tomography

scans. J Shoulder Elbow Surg 17:328-335, 2008

3. Scalise JJ, Codsi MJ, Bryan J, et al: The influence of three-dimensionalcomputed tomography images of the shoulder in preoperative planningfor total shoulder arthroplasty. J Bone Joint Surg Am 90:2438-2445,2008

4. Scalise JJ, Codsi MJ, Bryan J, et al: The three-dimensional glenoid vaultmodel can estimate normal glenoid version in osteoarthritis. J ShoulderElbow Surg 17:487-491, 2008

5. Walch G, Badet R, Boulahia A, et al: Morphologic study of the glenoidin primary glenohumeral osteoarthritis. J Arthroplasty 14:756-760,1999

6. Boardman ND, 3rd, Cofield RH: Neurologic complications of shouldersurgery. Clin Orthop Relat Res 368:44-53, 1999

7. Lynch NM, Cofield RH, Silbert PL, et al: Neurologic complications aftertotal shoulder arthroplasty. J Shoulder Elbow Surg 5:53-61, 1996

8. Nagda SH, Rogers KJ, Sestokas AK, et al: Neer Award 2005: Peripheralnerve function during shoulder arthroplasty using intraoperative nervemonitoring. J Shoulder Elbow Surg 16(Suppl 3):S2-S8, 2007

9. Gerber C, Pennington SD, Yian EH, et al: Lesser tuberosity osteotomyfor total shoulder arthroplasty. Surgical technique. J Bone Joint SurgAm 88(Suppl 1):170-177, 2006

10. Ponce BA, Ahluwalia RS, Mazzocca AD, et al: Biomechanical and clin-ical evaluation of a novel lesser tuberosity repair technique in totalshoulder arthroplasty. J Bone Joint Surg Am 87(Suppl 2):1-8, 2005

11. Scalise JJ, Ciccone J, Iannotti JP: Clinical, radiographic, and ultrasono-graphic comparison of subscapularis tenotomy and lesser tuberosityosteotomy for total shoulder arthroplasty. J Bone Joint Surg Am 92:

1627-1634, 2010