CHAPTER 30 – Nonarthroplasty Options for Glenohumeral Arthritis: Meniscal Allograft Resurfacing

Glenohumeral arthritis in young patients poses a particularly difficult treatment challenge. Nevertheless, independent of the patient’s age, nonoperative treatment is often initially effective. Accordingly, nonsteroidal anti-inflammatory medications, intraarticular injections of cortisone or commercially available hyaluronate solutions,^[*] appropriate activity modification, and physical therapy represent first-line therapy for patients with symptomatic glenohumeral degenerative joint disease.

Given the inherent problems with prosthetic glenoid resurfacing in this population (i.e., concerns about early glenoid loosening) and the difficulties with revision surgery posed by limited glenoid bone stock, prosthetic glenoid resurfacing is problematic in young, active patients. Arthroscopic débridement with capsular release often represents initial surgical therapy for this demanding population but can fail to provide long-term satisfactory results. ^{[4] [15]} Furthermore, traditional hemiarthroplasty and humeral head resurfacing offer reasonable treatment options for select young individuals with unipolar disease, such as osteonecrosis of the humeral head, but may not result in significant pain relief or functional improvement for those with bipolar processes.

In this challenging population, a growing number of techniques have evolved to address bipolar glenohumeral disease with biologic resurfacing of the glenoid. Several biologic interpositional options have been proposed with limited success, including use of the anterior capsule, Achilles tendon allograft, meniscal allograft, and, more recently, various soft tissue rotator cuff augmentation devices. ^{[1] [3] [5] [10] [16]} This chapter presents one such technique in which glenoid resurfacing is accomplished by an allograft meniscus combined with conventional humeral prosthetic replacement. The technique of glenoid resurfacing with a meniscal allograft tissue is well described. ^{[5] [16]} The premise behind the use of a human meniscus is that it provides a conforming biomechanical construct of fibrocartilaginous tissue with peripheral “liftoff,” theoretically decreasing contact forces across an otherwise arthritic glenohumeral joint.^[5]

* 
Note that use of commercially available hyaluronate solutions in the glenohumeral joint is not an indication approved by the Food and Drug Administration.

Preoperative Considerations

History

Patients often present with a history of previous surgical intervention. It is therefore essential to obtain all pertinent operative reports and intraoperative records detailing types of implants used. A typical history might include the following^[12]:

	•	Labral repair by use of a headed, bioabsorbable tack
	•	Labral repair by use of multiple bioabsorbable, knotless anchors[6]
	•	Labral repair by use of multiple metallic suture anchors
	•	Use of “thermal capsulorrhaphy” technique[11]
	•	Use of postoperative intraarticular continuous pain catheters with local anesthetic agents
	•	Postoperative course after labral repair in which the patient does well during the initial 6 to 9 months, then develops increasing shoulder pain, particularly at rest and at night with associated loss of glenohumeral motion
	•	Open, nonanatomic stabilization, such as a Magnuson-Stack or Putti-Platt procedure
	•	Traumatic anterior or posterior instability with subsequent pain after adequate rehabilitation or operative stabilization
	•	History of proximal humerus fracture with or without open reduction and internal fixation

Physical Examination

Typical findings include the following:

	•	Loss of both active and passive range of motion, typically most pronounced in external rotation
	•	Glenohumeral crepitation with range of motion
	•	Weakness with testing of the rotator cuff secondary to pain inhibition

Particular attention should be paid to the status of the axillary nerve after previous surgical intervention or traumatic instability.

Imaging

Radiography

	•	True anterior-posterior view in plane of scapula (Grashey view) to assess glenohumeral joint and to permit preoperative templating for humeral head replacement
	•	Axillary lateral view to assess glenohumeral joint and to permit preoperative templating in the case that prosthetic humeral head replacement is planned
	•	West Point axillary view to identify bone loss along the anterior inferior glenoid rim (i.e., a “bony Bankart” lesion)
	•	Stryker notch view to evaluate volume of bone loss with Hill-Sachs lesions

Other Modalities

Magnetic resonance imaging without contrast enhancement is performed to assess for the following:

	•	Presence of joint effusion
	•	Presence of loose bodies
	•	Synovitis
	•	Capsular thickening
	•	Status of glenohumeral cartilage ( Fig. 30-1 )
	•	Status of the rotator cuff
	•	Evidence of inflammatory reaction to bioabsorbable implants
	•	Glenoid version and evidence of posterior wear pattern

Computed tomography with multiplanar and three-dimensional reconstructions is performed to assess for the following:

	•	Prominent metallic hardware
	•	Volume of humeral head osteochondral loss in cases of Hill-Sachs or reverse Hill-Sachs lesions
	•	Volume of glenoid bone loss in cases of bony Bankart lesions
	•	Glenoid version and evidence of posterior wear pattern

Indications and Contraindications

The ideal candidate for biologic resurfacing is relatively young (younger than 50 years) and active and has well-preserved deltoid and rotator cuff musculature. Indications include the following:

	•	Symptomatic, bipolar glenohumeral degenerative joint disease
	•	Relatively concentric joint space loss without significant glenoid version or structural abnormalities
	•	Failure of nonoperative treatment options as well as less aggressive operative modalities (e.g., arthroscopic débridement)

Relative contraindications include the following:

	•	Infection
	•	Significant glenoid version abnormalities or structural loss of glenoid anatomy (i.e., biconcave glenoid)
	•	Significant neural injury or neuromuscular disorder
	•	Uncorrected instability
	•	Voluntary dislocators
	•	Patients unable or unwilling to comply with postoperative rehabilitation and restrictions
	•	Shoulder pain that is not limited to the glenohumeral joint

Arthroscopic débridement permits evaluation of the humeral and glenoid joint surfaces, removal of chondral loose bodies, and synovectomy when indicated. Selective capsular release, in the authors’ opinion, should always precede more significant operative treatment (
Fig. 30-2

).

At times, particularly in the setting of the shoulder that has had multiple operations, it can be difficult to determine whether the glenohumeral joint is the sole or primary pain generator on the basis of history, physical examination findings, and imaging studies. In these cases, a fluoroscopically guided glenohumeral injection of local anesthetic is potentially diagnostic of the cause of the patient’s pain. If significant pain relief is not received from the injection, the patient may not respond well to a resurfacing procedure. Furthermore, it is particularly important in a young population that the patient accept the limited-goals nature of the proposed procedure, that is, the intent is to provide reasonable pain relief and functional range of motion, not to restore normal shoulder function. The patient should understand that such a procedure may represent a temporary or “bridging” solution to the problem and that revision to conventional total shoulder arthroplasty may be indicated in the future. Most important, although the procedure may improve the patient’s symptoms, albeit to a lesser degree compared with glenohumeral replacement, it does not prevent or compromise this later revision to conventional total shoulder arthroplasty.

Surgical Planning

Allograft Sizing, Processing, and Preservation

The smallest available lateral meniscal allograft should be requested for glenoid resurfacing. The anterior and posterior horns of the lateral meniscus are situated relatively close to one another, giving it a smaller radius of curvature and making it a better geometric match for the glenoid than the medial meniscus. Fresh-frozen allografts that have tested free of viral and bacterial contamination are preferred. Theoretically, a contralateral lateral meniscus can be chosen and positioned such that the indentation for the popliteus tendon is superior near the biceps insertion. However, specific differences in surgical technique have not been well elucidated, and thus the surgeon’s preferences often prevail in determining exact graft position relative to the glenoid anatomy. Recipients should be educated about the small but finite risk of disease transmission with implantation of any allograft tissue. This risk is strongly mitigated through diligent donor screening policies and polymerase chain reaction testing for viral contaminants.

Surgical Technique

Anesthesia and Positioning

General anesthesia with endotracheal airway is preferred. Depending on the experience of the anesthesiology staff, regional anesthesia in the form of an interscalene block can serve as a useful adjunct, both for minimizing the need for intraoperative inhaled anesthetics and for reducing the need for postoperative, narcotic pain medication.

The patient is placed in a well-padded, modified beach chair position. The medial border of the scapula on the operative side is roughly aligned with the edge of the operating table; a small, rolled towel can be useful to protract the scapula further, facilitating intraoperative access to the face of the glenoid. The patient is positioned such that full glenohumeral extension and some degree of glenohumeral adduction is possible. An articulated arm-holding device, such as the McConnell arm holder (McConnell Orthopedic Manufacturing Company, Greenville, Texas), can be a useful adjunct.

Surgical Landmarks, Incisions, and Portals

Landmarks

	•	Coracoid process
	•	Acromion
	•	Deltoid insertion
	•	Axillary crease

Portals and Approaches

•

Deltopectoral approach

Structures at Risk

	•	Cephalic vein
	•	Musculocutaneous nerve
	•	Axillary nerve

Examination Under Anesthesia and Diagnostic Arthroscopy

Passive range of motion and stability are evaluated carefully and documented.

Specific Steps (
Box 30-1

)

1. Deltopectoral Approach

Surface landmarks—coracoid process, acromion, deltoid insertion—are marked on the skin. An 8- to 10-cm incision is made from a point immediately lateral to the lateral tip of the coracoid process in the direction of the deltoid insertion. The fat stripe indicating the interval between the medial border of the anterior deltoid and the superior border of the pectoralis major is located. The cephalic vein is identified, preserved, and taken laterally with the deltoid. Medial mobilization of the cephalic vein may be preferred to avoid inadvertent laceration as many of the surgical steps are performed medially with prolonged posterior displacement of the proximal humerus. The blades of a self-retaining retractor, such as a Kolbel retractor, are placed beneath the deltoid and pectoralis major. A Hohman retractor is placed superior to the coracoacromial ligament. The tip of the coracoid process is visualized, and the “red stripe” that marks the lateral border of the conjoined tendon is identified. By use of blunt dissection, a plane is developed deep to the conjoined tendon. The musculocutaneous nerve is palpated at its entry into the deep surface of the conjoined tendon. If the entry point is distal, then one of the blades of the self-retaining retractor may be safely placed deep to the conjoined tendon. Otherwise, gentle, intermittent manual retraction is used to avoid traction injury to the nerve.

Box 30-1 

Surgical Steps

1.    Deltopectoral approach    2.    Lesser tuberosity osteotomy    3.    Humeral preparation    4.    Inferior capsular release    5.    Glenoid preparation and meniscal allograft implantation    6.    Humeral implant, lesser tuberosity repair, and closure

2. Lesser Tuberosity Osteotomy

The arm is forward flexed and internally rotated. The long head of the biceps tendon is transected in its groove and sutured to the superior aspect of the pectoralis major insertion. The remnant of the long head of the biceps tendon is used as a guide to open the rotator interval and is then transected at its junction with the superior labrum. A 1-inch flat osteotome is then used to osteotomize the lesser tuberosity. A 5-mm-thick wafer of bone is taken, permitting reflection of the subscapularis (
Fig. 30-3

). Traction sutures are placed around the tuberosity fragment to assist with release. The axillary nerve is identified by palpation. If there is any doubt about its location, gentle dissection can be used along the inferior border of the subscapularis to visualize the nerve directly. A “360-degree release” of the subscapularis tendon is then performed, with release of the coracohumeral ligament superiorly, release of the anterior capsular reflection posteriorly, and release of subdeltoid and subcoracoid adhesions. The final element of the release—the inferior glenohumeral capsule—is addressed after humeral preparation.

3. Humeral Preparation

The humerus is maintained in a position of adduction and neutral flexion or extension as the capsular attachment to the humerus is released and the humerus is progressively externally rotated. Osteophytes are removed from the humerus, permitting identification of the anatomic neck. A freehand cut is made to match the native version and inclination of the proximal humerus, and a third-generation system that permits precise recapitulation of the native anatomy is used. As an alternative to the traditional stemmed component, a humeral head resurfacing implant can be used, permitting even greater preservation of proximal humeral bone stock but making access to the glenoid more challenging in some cases.

4. Inferior Capsular Release

Release of the inferior capsule completes the 360-degree release of the subscapularis and permits the posterior translation of the proximal humerus that is necessary for broad access to the glenoid. The traction sutures placed through the lesser tuberosity are pulled in a superior direction to put the inferior border of the subscapularis under tension. A plane is developed between the lower muscle border of the subscapularis and the anterior inferior capsule. This maneuver permits clear visualization along both the superior and inferior surfaces of the inferior glenohumeral capsule, allowing it to be released in a safe, controlled manner, with minimal risk to the axillary nerve. For additional safety, the release is performed at the capsulolabral junction, and a finger is maintained superior and posterior to the nerve. The inferior capsule typically is released until the triceps origin can be visualized.

5. Glenoid Preparation and Meniscal Allograft Implantation

A Fukuda or similar type of retractor is then placed behind the posterior rim of the glenoid, and the humerus is placed in a position of slight external rotation, relaxing the posterior capsule and facilitating glenoid exposure. An anterior glenoid retractor is placed into the subscapularis recess, and a Hohman retractor is placed along the superior edge of the glenoid. The labrum is débrided. The glenoid face is reamed lightly. A microfracture awl is used to make multiple perforations across the glenoid, spaced 5 mm apart. The lateral meniscal allograft is removed from its bony attachment, and the ends of the meniscus are sutured over one another with a heavy, nonabsorbable suture (
Fig. 30-4

). The degree of overlap is judged to allow the size of the prepared meniscus to approximate the size of the recipient glenoid. A Bankart awl or small drill bit is used to prepare the glenoid for transosseous sutures. A total of eight heavy, nonabsorbable sutures are used, starting at 12-o’clock and progressing in 90-minute intervals (
Fig. 30-5

). The meniscal allograft is marked similarly (
Fig. 30-6

). Posterior sutures can be difficult to place in transos seous fashion, and suture anchors can be used instead, placed in percutaneous fashion as one would do during an arthroscopic posterior labral repair (
Fig. 30-7

). By use of a small trocar-tipped or cutting needle, these sutures are now passed through the meniscal allograft, which is then advanced down the sutures and onto the face of the glenoid (
Fig. 30-8

). Sutures are tied in balanced fashion (12-o’clock, then 6-o’clock, and so on).

6. Humeral Implant, Lesser Tuberosity Repair, and Closure

The humeral head protector is removed and replaced with the humeral trial. The subscapularis is reduced to its insertion, and soft tissue balance is assessed. The trial is then removed, and a series of four holes are drilled through the bicipital groove along the lateral edge of the lesser tuberosity footprint. A series of three holes are drilled medial to the footprint. Four No. 5 nonabsorbable sutures are then placed through the holes in horizontal fashion. The superior-most of these sutures will pass through a lateral drill hole and then around the neck of the implant rather than through a matching medial drill hole. The humeral implant is then inserted. A small amount of cement can be used along the proximal aspect of the implant, but given the future possibility of conversion to total shoulder arthroplasty, the humeral stem is not cemented in its entirety. The previously placed No. 5 sutures are then passed around the lesser tuberosity wafer and tied down securely (
Fig. 30-9

). The humerus is internally and externally rotated to assess the security of the tuberosity repair. There should be no observable motion at the repair site. If desired, the rotator interval can be closed with the humerus in maximal external rotation. Motion, stability, and soft tissue balance are assessed once again. A drain is not used routinely. The deltopectoral interval is closed loosely with 2-0 Ethibond (Ethicon, Inc., Somerville, NJ) nonabsorbable sutures. Colored sutures can serve as a useful landmark in the event of future revision to total shoulder arthroplasty.

Postoperative Considerations

Follow-up

•

At 7 to 10 days for wound check and radiographs (true anteroposterior view in plane of scapula and outlet view)

Rehabilitation

0-6 weeks

	•	Pendulum exercises are begun.
	•	Lesser tuberosity osteotomy precautions: No active internal rotation, backward extension, or passive external rotation beyond the safe limit determined intraoperatively is allowed.
	•	A simple sling is worn for weeks 0 to 4.
	•	Active use of the elbow, wrist, and hand is encouraged.
	•	Active-assisted range of motion is permitted up to 120 degrees of forward flexion, 75 degrees of abduction.

7-12 weeks

	•	Active-assisted range of motion is progressed to active range of motion for internal rotation and backward extension as tolerated.
	•	Active-assisted range of motion is progressed to active range of motion in forward flexion, abduction, and external rotation as tolerated.
	•	Begin gentle deltoid and rotator cuff isometrics, with the exception of internal rotation.
	•	Start periscapular strengthening exercises.

13 weeks and beyond

	•	Progress strengthening, including resisted internal rotation.
	•	Perform gentle end-range stretching.

PEARLS AND PITFALLS

•    At times, particularly in the setting of the shoulder that has had multiple operations, it can be difficult to determine whether the glenohumeral joint is the sole or primary pain generator on the basis of the history and physical examination findings alone. In these cases, a fluoroscopically guided glenohumeral injection of local anesthetic can serve as a valuable diagnostic aid. Those patients who obtain minimal symptomatic relief from such an injection may not respond well to a resurfacing procedure.    •    When releasing the inferior capsule, rotate the inferior border of the Fukuda retractor laterally to increase the tension placed on the capsule, making it easier to visualize and to isolate. This can also facilitate tension on the posterior capsule if release is required to facilitate internal rotation.    •    When placing suture anchors along the posterior glenoid rim, first use percutaneous spinal needle localization from a posterior approach to establish direction and angle, then make a small stab incision and advance one of several commercially available cannulated guides with a sharp obturator through the incision onto the glenoid. After anchor placement, collect sutures out through the anterior deltopectoral approach. The same stab incision can be used to place two or three anchors.    •    A lesser tuberosity osteotomy probably does a better job of preserving anatomy and function than does a transtendinous approach through the subscapularis. Given the likelihood of future procedures in this young population, this approach may facilitate preservation of function in the shoulder with multiple operations.    •    Failure to comply with postoperative activity restrictions, particularly for the first 6 weeks, not only endangers the lesser tuberosity repair but may also impair healing of the meniscal allograft to the face of the glenoid.    •    Significant popping or clicking or the sensation of a “clunk” during the early postoperative period is likely to signify failure of fixation at the meniscus-glenoid interface.

Complications

Complications are similar to those of total shoulder arthroplasty:

	•	Injury to the axillary nerve
	•	Injury to the musculocutaneous nerve
	•	Failure of the lesser tuberosity repair
	•	Infection
	•	Incomplete relief of pain
	•	Failure of the meniscus-glenoid interface

Results

Published and presented results of biologic resurfacing procedures are limited, and those available reflect only short- and intermediate-term outcomes (
Table 30-1

).

Author	Procedure	Followup	Outcome
Burkhead and Hutton[3] (1995)	Humeral hemiarthroplasty	34 months	Range of motion in forward flexion improved from 81 to 137 degrees
	Biologic resurfacing of glenoid with either fascia lata autograft or anterior capsule		Neer’s full exercise rating system: 8 excellent, 2 satisfactory results
Krishnan et al[10] (2004)	Humeral hemiarthroplasty	3 years	ASES score improved from 25 to 75
	Biologic resurfacing of glenoid and acromion with Achilles tendon allograft		Range of motion in forward flexion improved from 35 to 95 degrees
Argo et al[1] (2005)	Arthroscopic interposition grafting with porcine xenograft	13 months	VAS for pain dropped from 8 to 2
			Range of motion in forward flexion improved from 90 to 150 degrees
			Range of motion in abduction improved from 70 to 120 degrees