Surgical release for stiff frozen shoulders

Surgery to remove scar tissue and release contractures can lessen pain and improve function for stiff shoulders that have not responded to rehabilitation or physical therapy

Last updated: Wednesday, January 26, 2005

Introduction

This is the information which might be shared with patients as they consider a surgical release for shoulder stiffness. Before it can be applied to a specific clinical situation, however, it needs to be tailored to the patient, the problem, and the surgeon.

Home exercise program

Most patients with stiff shoulders can improve their comfort and function with a home exercise program. Your doctor may consider an open surgical release for the few stiff shoulders which do not improve with a persistent effort at the exercises.

Purpose

The purpose of the surgical release is to cut through the adhesions, scar tissue, and other structures that may be interfering with the motion of your shoulder.

Alternatives to surgery

This procedure is purely elective. The alternatives are to continue with the exercises or to accept the current range of motion.

Risks

Open release is a surgical operation; as such it carries some risks. These include the risk of anesthesia, infection, nerve injury, blood vessel injury, excessive looseness and instability of the shoulder, persistent or increased shoulder stiffness, fracture, increased pain, or the need for repeat surgery.

After the surgery

After surgery, it is essential that you resume the stiff shoulder exercises so that adhesions will not have an opportunity to reform.

While an experienced surgeon can loosen the shoulder at surgery, you are the only person who can maintain the motion during the healing period. These exercises will need to be continued for up to a year after your surgery. If you have concerns about your ability to carry out this important aspect of your treatment, please discuss this with your doctor before you undertake surgery.

You are likely to be in the hospital until your exercise program is well launched. At the time of discharge your doctor will encourage you to be physically active and to avoid narcotic and sleeping medications. You will be unable to drive for at least two weeks after this procedure, so you should make appropriate provisions for getting around during this time.

Who should consider surgery

Open surgical release is considered for informed, consenting patients if the manipulation is not indicated or successful in reestablishing motion in a stiff shoulder. The patient's role in the recovery process is emphasized.

Surgical approaches

The type of stiffness dictates the surgical approach to the refractory stiff shoulder.

Usual approach

We usually approach a post-surgical stiff shoulder through an incision that provides access to the previous surgical site. This is because the densest adhesions and scar are usually located beneath the surgical incision. The idiopathic frozen shoulder is reached through a deltopectoral approach, which allows access to the rotator interval, the motion interface, the subscapularis, and the glenohumeral joint capsule. The surgical release is analogous in many ways to the subscapularis and capsule release performed during a glenohumeral arthroplasty.

We proceed sequentially through a series of distinct stages of shoulder release, reassessing the range of motion after each stage. We continue through these stages until the desired motion is obtained.

Stage one

Re-establishment of the humeroscapular motion interface: Our in vivo MRI studies demonstrated that there is normally a substantial excursion at the humeroscapular motion interface. In post-surgical and post-traumatic stiff shoulders, adhesions or "spot welds" are common between the deltoid, acromion, coracoacromial ligament, coracoid, and coracoid muscles on one hand and the rotator cuff and humerus on the other. These spot welds can virtually eliminate motion at the interface. Thus, each area of the interface needs to be smooth and free of adhesions for the shoulder to achieve its normal range. At times the motion interface can be obscured and difficult to identify.

In the "totally stuck shoulder" we start under the acromion, knowing that it is part of the outer aspect of the motion interface. Dissecting beneath the acromion and coracoacromial ligament with a knife, we can free the subjacent cuff tissue. By rotating the humerus internally and externally during this step of the dissection we continue the dissection under the coracoacromial arch to the coracoid. Then the sharp dissection proceeds beneath the coracoid and coracoid muscles, freeing the subjacent subscapularis muscle.

Adhesions between the coracoid muscles and the subscapularis cause a major limitation of external rotation owing to the magnitude of interfacial motion here. It must be remembered that the brachial plexus, especially the musculocutaneous and axillary nerves, are close by and vulnerable. Thus we stay lateral to the coracoid muscles (the "safe side") dissecting on the surface of the subscapularis as it is externally rotated, rather than diving medial to the coracoid muscles (the "suicide").

In a similar manner, sharp dissection continues laterally from the acromion to reestablish the motion interface between the deltoid and the rotator cuff. Again, the nerve supply, in this case the branches of the axillary nerve, lie in the motion interface. We avoid them by keeping our sharp dissection on the superficial aspect of the rotator cuff and proximal humerus. If the dissection enters the deltoid muscle, its nerve supply, the axillary nerve, is at risk.

Stage two

Opening the rotator interval: As our cadaver research has demonstrated, tightness at the rotator interval can substantially restrict the range of glenohumeral motion. We release the rotator interval by sharply dissecting the subscapularis and supraspinatus tendons free from their moorings to the base of the coracoid. We verify the completeness of this release by passing a blunt elevator between the tendons on both sides of the coracoid process.

Stage three

Reestablishment of subscapularis length and excursion: The subscapularis and anterior capsule may be contracted and scarred, particularly after previous anterior shoulder injury or surgery. We perform a coronal plane "Z" lengthening of the subscapularis tendon and capsule using a step cut. We cut the superficial lateral aspect of the tendon at the lesser tuberosity near the long head of the biceps. We then split the tendon medially in the coronal plane. Finally, we complete the medial aspect of the cut by transecting the remaining tendon and capsule adjacent to the glenoid labrum. At the conclusion of the procedure we will suture the lateral end of the superficial flap to the medial end of the deep flap.

Each centimeter of subscapularis lengthening gained by the step cut increases external rotation by approximately 20 degrees. Prior to the closure, we perform a "360 degree" release of the subscapularis tendon from the coracoid muscles anteriorly, the axillary nerve below, the capsule and scapular neck posteriorly and the coracoid above. This release should reestablish the normal "bounce" and excursion of the subscapularis.

Stage Four

Release of the capsule: Capsular tightness is the major component of an idiopathic frozen shoulder, but it may also be a major component of post-traumatic and post-surgical stiff shoulders. In the surgical release, we section the tight capsular tissue just lateral to the glenoid labrum. The capsule can be released selectively or circumferentially according to the pattern of stiffness. A circumferential capsular release can be started anterosuperiorly, then carried down the anterior glenoid. We release the inferior capsule sharply while a finger protects the axillary nerve. We expose the origin of the triceps from the infraglenoid tubercle with this release. We insert a humeral head retractor into the joint and twist it slightly to tension the posterior inferior capsule so that it can be safely sectioned. By twisting the retractor a little more with each bit of posterior capsular release, we can safely release the posterior capsule up to the origin of biceps tendon at the supraglenoid tubercle. The lengthened subscapularis tendon is then sutured to the capsule attached to the lesser tuberosity.

Figure 4 - Releasing the inferior capsule sharply while a finger protects the axillary nerve

Figure 5 - Releasing the posterior capsule up to the origin of biceps tendon at the supraglenoid tubercle

Adequate release

The hallmarks of an adequate release are:

translation of the humeral head on the posterior drawer test of at least 1.5 centimeters,
a "scarecrow" test demonstrating almost 90 degrees of internal rotation of the arm elevated 90 degrees in the zero degree thoracic plane,
at least 45 degrees external rotation with the arm at the side, and
total elevation of the arm to at least 140 degrees.

After the surgery

Continuous passive motion and exercise

As soon as the procedure is completed, we place the arm in continuous passive motion. Early motion achieves several goals. It prevents formation of adhesions or scarring during the critical early healing period. It also demonstrates to the patient that the shoulder can and should be moved immediately. Finally, early movement seems to increase the comfort, speed, and completeness of motion recovery. The use of the continuous passive motion after surgery is greatly facilitated by a brachial plexus block for the surgical procedure. This type of anesthesia can give 12 to 18 hours of post-operative anesthesia, allowing the awake patient the opportunity to observe the increase in motion gained by the procedure without experiencing early post-operative pain.

On the first day after surgery, the patient resumes the stiff shoulder exercises. Each day the patient is in the hospital, we plot the range of elevation (overhead reach) and rotation on charts posted in the patient's hospital room. These charts (see figures) provide positive reinforcement for the patient's progress.

Ideally, before discharge the patient can demonstrate comfortable assisted motion to 140 degrees of elevation, 40 degrees of external rotation, internal rotation until able to reach T12 with the thumb, and cross body adduction comparable to the normal side. The wall charts reflect these discharge goals. With this program, the patient becomes the center of the treatment team and is motivated to continue the exercises after discharge.

The two-year follow-up data for twelve patients having open surgical release for refractory frozen shoulders are encouraging (see figure).