History
A patient with multidirectional instability (MDI) most often presents with complaints of a generalized painful or sore shoulder, which is usually worse with activity or with certain arm positions. Instability symptoms perceived by the patient, such as dislocation, subluxation, or functional symptoms (eg, catching, locking), are less commonly reported than pain. [20] In fact, many patients may not appreciate or describe any actual sense of instability.
Symptoms may follow a roller-coaster pattern and may be aggravated by overhead activity, carrying objects at the side, overuse, or injury. These symptoms are relieved by rest and support of the arm. Nocturnal pain is variable.
The patient usually denies a history of frank traumatic dislocation but may describe subluxation or looseness, even with activities of daily living (ADLs). This history should provoke suspicion of and search for a multidirectional pattern of laxity, particularly if laxity is bilateral or posterior. The combination of posterior and inferior laxity is classic, according to Neer and Foster. [2]
An athletic history may be contributory. [21] Patients with a predisposition to MDI who are engaged in sports that are repetitively stressful to the shoulder girdle (eg, swimming, throwing, or racquet sports) may have a difficult time with consistent high activity levels. In many cases, the initial presentation is of an adolescent athlete who reports vague trauma, though it is the repetitive microtrauma combined with the capsular laxity that is the actual pain generator.
Perhaps one of the most confusing presentations is that of concomitant impingement. Not uncommonly, a patient with MDI may complain chiefly of pain with overhead use, especially if there is involvement with overhead athletics, such as throwing, volleyball, swimming, or racquet sports. Pain, in this case, may be minimal with the arm at the side. Tibone et al [22] showed that therapeutic management directed at the diagnosis of impingement and rotator-cuff pathology in patients participating in overhead activities may be unsuccessful.
Underlying instability always must be considered in those who report a painful shoulder, especially in the younger patient who is involved in vigorous activities above the shoulder.
Impingement symptoms (ie, pain with the arm at 90° or more) may be secondary to glenohumeral hypermobility and superior humeral head translation, regardless of acromial arch architecture.
Physical Examination
A notable highlight of MDI on examination is the bilaterality of physical findings. Although active range of motion (AROM) may be guarded, there are no passive limits.
A good stability examination yields underlying glenohumeral hyperlaxity if adequate relaxation can be achieved. The pathognomonic feature of MDI is demonstration of the sulcus sign—the hallmark of the inferior component of the capsular laxity. Again, with adequate relaxation, a patient examiner demonstrates laxity beyond the normal limits with anterior and posterior testing. Grade may be variable, and anterior and posterior components need not be symmetrical.
If the patient is unable to relax, an examination under anesthesia (EUA) may be required to demonstrate increased glenohumeral anterior and posterior translation, as well as inferior translation (ie, sulcus sign). More often than not, these findings are symmetrical.
Examination of the labrum (eg, labral grind test, superior labrum anterior and posterior lesion [SLAP] test) also may reveal positive findings, with or without true labral anatomic abnormalities. Furthermore, apprehension testing also may be positive, usually in the direction of the chief component of instability.
For example, anterior apprehension findings in the external rotation and abducted position may suggest a predominant anterior-inferior MDI pattern, with or without positive relocation, crank, or fulcrum tests. Alternatively, posterior apprehension signs or a positive jerk test may suggest a predominant posterior-inferior pattern.
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Labral features characteristic of multidirectional instability; normal appearing. Note: Although there is only 2 lb of traction, it is very easy to push arthroscope between humeral head and glenoid surfaces (ie, drive-through sign). Courtesy of Daniel C Wnorowski, MD.
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Hypoplastic labrum. Courtesy of Daniel C Wnorowski, MD.
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Posterior and superior aspects of humeral head of shoulder with multidirectional instability are pristine. Typically, there is no Hill-Sachs lesion, even if there has been subluxation. Courtesy of Daniel C Wnorowski, MD.
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Posterior aspect of humeral head of shoulder with multidirectional instability is without Hill-Sachs lesion. Also note patulous capsule. Courtesy of Daniel C Wnorowski, MD.
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Multidirectional instability of right shoulder from posterior portal. Patient is in lateral position with minimal arm traction (2 lb). Note glenohumeral inferior subluxation, with humeral head perched on normal-appearing anterior-inferior labrum. Courtesy of Daniel C Wnorowski, MD.
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Normal subacromial space in patient with multidirectional instability and history of secondary impingement. Courtesy of Daniel C Wnorowski, MD.
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Cosmetically ideal modified axillary incision for open inferior capsular shift. Incision will be made in apex of axillary crease. Courtesy of Daniel C Wnorowski, MD.
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Open approach via axillary incision. Self-retaining retractor is shifted cephalad after mobilization of skin flaps. Courtesy of Daniel C Wnorowski, MD.
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Rotator cuff interval is closed with nonabsorbable suture. T-capsulotomy incision is planned with dotted lines.
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Superomedial (SM) and inferomedial (IM) flaps are created by T-capsulotomy incision. First, IM flap will be advanced superiorly and laterally; then, SM flap will be advanced inferiorly over top of IM flap.
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Finished repair with superomedial (SM) flap advanced inferiorly, overlapping previous inferomedial (IM) flap advancement. Note how axillary pouch has been eliminated.
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Suture passer device (Spectrum; ConMed Linvatec, Largo, FL) is placed through working cannula, then through "pinch" of posterior capsule, and also through posterior labrum. Courtesy of Daniel C Wnorowski, MD.
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Next, with monofilament suture and all-arthroscopic knot-tying technique, knot is tied, thus plicating capsular "pinch" to labrum. Courtesy of Daniel C Wnorowski, MD.
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Process in image above is repeated, placing second, slightly more superior suture and knot. Courtesy of Daniel C Wnorowski, MD.
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Close-up of third "pinch." Courtesy of Daniel C Wnorowski, MD.
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Close-up of third labral pass. Courtesy of Daniel C Wnorowski, MD.
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Third suture is placed. Courtesy of Daniel C Wnorowski, MD.
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Completed third knot. Courtesy of Daniel C Wnorowski, MD.
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Depending on degree of capsular laxity, one may take "double tuck" to achieve additional plication and tightening, at risk of added range-of-motion restriction. Courtesy of Daniel C Wnorowski, MD.
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View from posterior portal of "interval closure"; with suture passer device, monofilament suture is placed at margins of cuff interval. Courtesy of Daniel C Wnorowski, MD.
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Knot is tied through anterosuperior portal, thus closing rotator-cuff interval. Courtesy of Daniel C Wnorowski, MD.
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Second of two anchors placed for posterior plication, given hypoplastic posterior labrum, prior to suture passage. Note anchor placement on posterior margin of articular surface, not on neck of glenoid. This allows for "capsulolabral reconstruction" (see next image). Courtesy of Daniel C Wnorowski, MD.
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After passage of anchor-based suture and completion of plication and "capsulolabral reconstruction," augmenting hypoplastic labrum with capsular fold. Note that these are permanent sutures and therefore are tied off glenoid to avoid knot-articular surface impingement. Courtesy of Daniel C Wnorowski, MD.
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Monopolar radiofrequency probe applied to posterior capsule with grid technique after treatment to 65°C. Ellipses indicate areas of linear application (grid lines). Rectangle indicates untreated island between lines. Courtesy of Daniel C Wnorowski, MD.
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Patient is in beach-chair position; anterior portal. Note capsular laxity with probe and blunted labrum. Photo courtesy of Bradley S Raphael, MD.
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Suture passer device (Suturelasso; Arthrex, Naples, FL) is placed through working cannula, then through "pinch" of posterior capsule and also through posterior labrum; it is threaded with nonabsorbable suture that is tied with knot away from articular cartilage. Photo courtesy of Bradley S Raphael, MD.
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Next, with monofilament sutures and all-arthroscopic knot-tying technique, knots are tied, thus plicating capsular "pinch" to labrum. Photo courtesy of Bradley S Raphael, MD.
