Inestabilidad congenita de_hombro_opciones_de_ev_y_tto


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Inestabilidad congenita de_hombro_opciones_de_ev_y_tto

  1. 1. [ CLINICAL COMMENTARY ] PATRICK GUERRERO, DO¹ MD² MD³ DPT, OCS4 Congenital Instability of the Shoulder Joint: Assessment and Treatment Options ongenital instability is a form of multidirectional instability ing shoulder activity associated with C (MDI), which is difficult to diagnose and treat in great part due to a lack of understanding of the pathogenesis of this condition. Congenital instability is not caused by a traumatic event; rather, it is present in some individuals from birth. The exact incidence is not known because the etiology is atraumatic and there is symptoms such as pain, discomfort, par- esthesia, apprehension or fatigue, then the term instability is used. Because of instability in multiple directions, these individuals often present with global shoulder pain, which usually cannot be a broad spectrum of pathology, ranging from mild pain to dislocations. pinpointed to a specific location. Second- ary rotator cuff impingement is also seen Variations in definition, such as voluntary ity when, in fact, it may only be an indi- in this population, and microtraumatic or involuntary instability, or traumatic cation of laxity.19,21 Finally, instabilities in events, caused during participation in versus atraumatic instability, make the di- 2 directions, such as antero-inferior and sports such as gymnastics, swimming, agnosis of this entity even more difficult.48 postero-inferior, have been grouped as and weight training, can precipitate in- In some previous studies the diagnosis of different entities from MDI.1,5,45 stability in a patient with laxity. Some pa- MDI was obtained based on the ability Laxity of the glenohumeral joint is an tients with MDI may report symptoms in to sublux or dislocate the glenohumeral asymptomatic hypermobile joint with both shoulders, which is consistent with joint even in the absence of symptomatic the ability to maintain centering of the generalized capsular laxity. instability.32,64 Other authors have used humeral head in the glenoid fossa. When Physical therapy has become the pri- the sulcus sign to define inferior instabil- there is loss of this centering ability dur- mary approach for the treatment of MDI as we have gained more knowledge and Congenital instability of the Because multidirectional instability can be difficult experience with the treatment of these shoulder is a form of multidirectional instability to diagnose, this article will attempt to provide individuals.9 Neer and Foster53 were the not caused by a traumatic event. It is believed the clinician with a better understanding of the first to describe the concept of MDI and that excess laxity may be responsible for an overly pathophysiology involved in this condition, the attributed the pathology to redundancy of elastic capsule and, therefore, can contribute to necessary steps for diagnosis, and considerations the capsule. Other authors have postulat- multidirectional instability. Minor microtraumatic for treatment. A comprehensive guide to both ed that MDI was due to an enlargement events can progressively lead to the develop- nonoperative and operative treatment is reviewed ment of pain and lead to instability. The current of the capsule,29 incompetence of the gle- in this article, as well as the surgical techniques preferred treatment is largely nonoperative with used to decrease the capsular volume. nohumeral ligaments,34 or increased in extensive rehabilitation of the dynamic restraints glenohumeral volume.67 Lipitt et al42 and Level 5. J Orthop Sports of the shoulder complex. In recalcitrant cases, Thomas and Matsen70 have described a Phys Ther 2009; 39(2):124-134. doi:10.2519/ operative intervention to restore stability may be classification of what we now refer to as jospt.2009.2860 necessary. It is of paramount importance to notice TUBS (traumatic, unilateral, associated the directions of instability and to address each of capsular plication, inferior capsu- Bankart lesion, and requires surgery) them. Surgical procedures include open capsular lar shift, multidirectional instability, rotator interval shift, as well as arthroscopic capsular plication. closure, shoulder and AMBRII (atraumatic, multidirec- tional, bilateral, rehabilitation, inferior 1 Orthopedic Surgery and Sports Medicine Physician, Central Cal Orthopedic, Turlock, CA. 2 Associate Professor of Orthopedics, University of Massachusetts Medical School, Worcester, MA; Chief of Sports Medicine, University of Massachusetts Medical School, Worcester, MA; Director of Sports Medicine Fellowship Program, University of Massachusetts Medical School, Worcester, MA. 3 Assistant Professor of Orthopedics, University of Massachusetts Medical School, Worcester, MA; Assistant Director, Sports Medicine Fellowship Program, University of Massachusetts Medical School, Worcester, MA. 4 Physical Therapist, Orthopedics/Sports, University of Massachusetts Medical School, Worcester, MA. Address correspondence to Dr Brian Busconi, U-Mass Memorial-Hahnemann, Orthopedic Surgery, 281 Lincoln Street, Worcester MA 01605. E-mail: 124 | february 2009 | volume 39 | number 2 | journal of orthopaedic & sports physical therapy
  2. 2. capsular shift, interval closure). Although ligaments, which act as static stabilizers muscles. These muscles work to reach simplistic, this classification allows us to of the joint. The superior glenohumeral equilibrium and counterbalance to provide guide treatment accordingly. This article ligament (SGHL) is located in the an- stability to the glenohumeral joint.76 will focus on the latter group of individu- terosuperior quadrant, along with the With congenital MDI, the glenoid can als, discussing the potentially causative middle glenohumeral ligament (MGHL). be hypoplastic, have increased retrover- factors for the condition, as well as the The MGHL is known to provide anterior sion, or have a decreased antero-poste- possible treatment strategies. and inferior stability when the shoulder rior diameter.29 Based on arm elevation is in a midabduction position.56 The an- and 3-dimensional magnetic resonance terior and posterior bands of the inferior imaging (MRI) analysis in patients with glenohumeral ligament (IGHL) provide hypoplastic postero-inferior glenoid rim, actors that can be associated anterior and posterior stability, respec- Inui et al31 demonstrated excessive mo- to MDI include excessive laxity, in- tively, when the shoulder is abducted tion of the humeral head in the posterior adequate glenoid concavity, glenoid to 90°.47 The coracohumeral ligament and inferior direction. Just as important hypoplasia, muscular imbalance, and lack (CHL), spanning from the coracoid pro- as the bony anatomy and the rotator cuff of neuromuscular control.26,34,67 Some in- cess to the humeral head, along with the function is scapular motion. For instance, dividuals may present with collagen dis- SGHL and the MGHL, when subjected to it is not uncommon to see individuals orders, such as Ehlers-Danlos syndrome, translational forces, resist anterosuperior with MDI having abnormal upward ro- in which minor injuries often precede the motion of the humeral head when the tation of the scapula during arm abduc- development of instabilities.34 Shoulder shoulder is in flexion and slight abduc- tion.55 There is a delay in scapular motion instability occurs when there is inability tion. These ligaments also provide poste- in this population, in which less upward to keep the humeral head centered in the rior and inferior stability.6,68 rotation of the scapula causes less in- glenoid when the arm is elevated.31 Al- Along with the glenohumeral liga- clination of the glenoid in the scapular though most people with MDI experience ments, the rotator cuff interval plays an plane, and, therefore, less stability in the involuntary subluxations and dislocations, important role in providing shoulder sta- inferior direction.33 a select and unusual group may have the bility. The interval is bordered superiorly Increased retroversion of the glenoid ability to voluntarily sublux or dislocate by the anterior margin of the supraspina- can cause posterior instability by decreas- their shoulder, to possibly provide some tus and inferiorly by the superior border ing the effective bony restraint. The same form of psychological gratification. of the subscapularis. The apex of the in- can be inferred from having a glenoid It is of paramount importance to ac- terval consists of the transverse humeral with a decreased anteroposterior diam- knowledge that to diagnose clinical insta- ligament and its base the coracoid pro- eter. MDI appears to be a rather gradual bility, symptoms, such as pain or feeling cess. A large interval increases translation progression of multiple variables. Patients of excessive looseness, must be present. of the humeral head in the anterosuperior usually present with bilateral laxity and With shoulder instability, 1 or more of the direction. Because the SGHL and CHL may have hereditary congenital laxity. mechanisms involved in maintaining a strengthen the interval, when enlarged it When this laxity is compounded with re- tight and congruent articulation is failing. can also cause posterior instability. petitive overhead activities, the structures One of the mechanisms involved in pro- Dysfunction of the dynamic stabiliz- already predisposed to stretch, that serve viding stability of the glenohumeral joint is ers may also lead to MDI. The rotator cuff to provide stability, gradually fail. This the negative intra-articular pressure. This musculature creates compression of the failure then gives rise to symptomatic lax- negative pressure provides stability even humeral head against the glenoid and cre- ity or instability. Patients with MDI may when the rotator cuff musculature has ates stability in the midrange of shoulder present with glenohumeral joint instabil- been removed, until an incision is made motion. This compression becomes more ity in 22,56 or 3 major directions (anterior, in the capsule and allows air to enter.7 The effective by virtue of having a concave gle- inferior, and posterior).59 Inferior insta- magnitude of this negative pressure is ap- noid and a convex humeral head. The role bility is one of the major clinical findings proximately 13.6 kg.23 It is, therefore, pos- of the glenoid labrum adds to the concav- in individuals with MDI. tulated that a larger glenohumeral joint ity/compression effect, thereby increasing The amount and composition of colla- volume would require a larger magnitude stability by 50%.46 The primary dynamic gen, elastin, as well as collagen cross-link- negative pressure (“vacuum effect”) to stabilizers are the rotator cuff musculature ing, may be different in people with MDI. keep the joint surfaces congruent in the (supraspinatus, infraspinatus, teres minor, In a histological study, patients with MDI relaxed state,79 as well as with inferior and subscapularis), the deltoid, and the and anterior instability did not differ sig- loading (translation) of the joint.46,47 long head of the biceps. The secondary nificantly on the amount of collagen in Another possible factor for MDI in- dynamic stabilizers include the teres ma- their tissue; however, those who failed volves incompetence of the glenohumeral jor, latissimus dorsi, and pectoralis major MDI surgery did have a smaller amount journal of orthopaedic & sports physical therapy | volume 39 | number 2 | february 2009 | 125
  3. 3. [ CLINICAL COMMENTARY ] of collagen fibrils.17 In a different study, Grading Inferior Laxity a comparison of collagen crosslinks, fi- Using the Sulcus Sign bril diameter, amino acid composition, and elastic fibers of the glenohumeral Grade Translation (Inferior) joint capsule and skin was made among 1 1 cm translation 4 groups. The groups included individu- 2 1-2 cm translation als with unidirectional instability, MDI- 3 2 cm translation primary surgery, MDI-revision surgery, and no instability. Compared to those with a normal capsule, the capsule of the Grading Anterior and Posterior Laxity individuals with unidirectional instabil- Using the Load-and-Shift Test to Assess ity and MDI-primary surgery had more Translation of the Humeral Head With stable and reducible collagen cross-links, Respect to the Glenoid Rim greater fibril diameter, more cysteine, and a higher density of elastin staining. Grade Translation In individuals with MDI-revision sur- 0 No translation gery, more reducible cross-links, small- 1 50% translation of head er-diameter collagen fibrils, decreased 2 Translation onto the glenoid rim fibril density, and increased elastin were 3 Translation over the glenoid rim observed, when compared to those in the 4 Complete dislocation other groups. Skin collagen fibril diam- eter was significantly less in the MDI when the sense of instability is present. as well as externally rotated to assess for groups compared to the individuals in Some other patients may be able to self- patency of the rotator cuff interval or the the group with unidirectional instability. reduce their glenohumeral joint. SGHL. This ligament tightens with gle- The authors hypothesized that repeated Inspection of both shoulders for com- nohumeral external rotation (ER), and, capsular deformation may lead to chang- parison is performed to determine any by keeping the arm at the side, the infe- es that increase capsular strength and differences between the symptomatic rior glenohumeral ligament does not play resistance to stretching, and that there and asymptomatic shoulder. As with any a role in providing inferior stability. may be an underlying connective tissue examination, beginning with the nonaf- The load-and-shift test ( ) is abnormality in individuals with MDI.63 fected shoulder may allow the examiner to used to assess anterior and posterior notice any laxity, as well as get the neces- translation ( ).26 It is performed sary patient’s confidence prior to examin- with the examiner’s hand applying an ing the symptomatic limb. The examiner anterior-to-posterior translation on the needs also to pay particular attention to humeral head, and the other hand hold- T he evaluation begins by taking a good history. Patients present- scapular motion, including winging and ing the arm while applying an axial load ing with MDI may not be able to protraction. in the direction of the glenoid center. provide adequate information to obtain A method to determine MDI is by This centering of the humeral head on a detailed history, mainly due to the measuring translation beyond the gle- the glenoid allows better assessment of vagueness in symptom presentation. The noid rim in 2 or more directions. Our translation by starting at the midpoint. usual presenting symptom in our clinic is preferred tests are the sulcus sign and An anterior and posterior force is then global pain around the shoulder, rather load-and-shift test.26,53 These tests are applied, and the translational motion is vague in location, and most often activity reliable and simple to perform. The sul- graded based on the amount of humeral related. Attention should be paid to pro- cus sign is performed by applying infe- head riding over the glenoid rim.26 voking maneuvers, as well as perceived rior traction to the arm with the arm at The sulcus sign and the load-and-shift direction of instability. Often patients the patient’s side ( ). An increase test indicate inferior laxity and anterior with MDI present with scapular dyski- in space greater than 1 cm between the or posterior laxity, respectively, and not nesia, as well as patellofemoral pain syn- humeral head and the lateral edge of the necessarily instability. Careful attention drome. Ill-defined pain and weakness in acromion is considered abnormal ( should be paid to pain and apprehension the shoulder are also common presenta- 1).53 It should be added that inferior laxity, when performing these tests. tions in this population.20 Of note is that assessed with the arm in neutral abduc- Elbow hyperextension and knee recur- patients may not be able to accurately tion (arm at the side), needs to be mea- vatum, as well as thumb hyperextension, determine the direction of subluxation sured with the arm in neutral rotation, should be evaluated. In athletes, the type 126 | february 2009 | volume 39 | number 2 | journal of orthopaedic & sports physical therapy
  4. 4. an extensive course of a well-designed rehabilitation program and continue to have shoulder symptoms. P lain radiographs may show evidence of a hypoplastic glenoid, Considering the risk for subluxation, increased retroversion, and/or an individual requires rotator cuff muscle evidence of glenohumeral erosion due balance and strength to properly contain to chronic subluxation or dislocations. the humeral head within the glenoid. Radiographs of a true antero-posterior Scapulothoracic motion should also be (AP) view, a scapular Y view, and an axil- evaluated and any dysfunction correct- lary view should be obtained. With plain ed.33,53 The examiner should assess this Sulcus sign. Note skin indentation below radiographs, especially the axillary view, motion by having the patient elevate the the lateral acromion when traction is applied the amount of glenoid retroversion can arms simultaneously, while observing if inferiorly on the arm. be assessed.29,32 This retroversion is de- both scapulae move in symmetry. With fined as the angle made by the glenoid instability and dysfunction, the scapula with respect to the plane of the scapula of the affected side will often shift more on an axial view. Computed tomography quickly, move more lateral, or wing away (CT) may be needed to study the details from the ribcage. Most authors have ac- of the glenoid architecture, especially knowledged the importance of strength- when plain radiography does not pro- ening exercises of the rotator cuff and vide sufficient visualization of the bony scapular stabilizers as a means to con- anatomy.29,32 trol excessive translation of the humeral MRI arthrography may help iden- head.27 Postural education should also be tify capsular redundancy, as well as aid emphasized to encourage scapular retrac- in preoperative planning for addressing tion and minimize scapular protraction Load-and-shift test. Anterior and possible labral tears, including superior during daily activity for optimal humeral posterior force is alternately applied while providing compression force toward the glenoid using the labrum anterior posterior (SLAP) tears. head congruity in the glenoid41 and in- humerus and humeral head. The routine use of CT or MRI arthrog- crease performance of the rotator cuff raphy may be unnecessary, unless there muscles.62 Proper posture is critically im- of sport participation may provide clues is the need to discern between other pos- portant in these individuals, as protract- to the kinds of injuries they may have. sible and confusing diagnoses. Kim et al39 ed scapulae can lead to further anterior Participation in swimming, volleyball, reported that patients with atraumatic instability.41 Posture is emphasized with tennis, throwing, and gymnastics should postero-inferior instability tend to have verbal, manual, and visual cues. raise clinical suspicion of glenohumeral increased bony and labral retroversion, To optimize the strengthening pro- joint instability. An overlapping of symp- decreased labral height in the postero- gram, the periscapular stabilizers, lower toms is present between acquired and inferior quadrant, and shallower glenoid trapezius, middle trapezius, upper trape- congenital instability, because participat- depth in the middle and inferior planes. zius, rhomboids, and serratus anterior ing in sports may exacerbate the underly- Weishaupt et al73 demonstrated that should be addressed first, as the rotator ing congenital instability condition. The patients with recurrent posterior insta- cuff muscles originate from the scapula,51 position of the arm when symptoms are bility had a deficiency of the postero- and scapular stability is required to pro- present should also be investigated. For inferior glenoid rim. Also, a significant vide a solid base for rotator cuff function. instance, during throwing, pain during difference in the glenoid version is seen The ideal exercises for this phase of re- the follow-through phase could indicate between stable and unstable shoulders habilitation were determined through posterior instability, in contrast to pain with a greater degree of retroversion in electromyography (EMG) by Moseley et during the cocking motion, which may the unstable shoulders. al.52 These exercises consist of elevation indicate anterior/inferior instability. It is in the plane of the scapula for the up- often difficult to determine if the insta- per trapezius: press-downs (from a sit- bility began prior to sports participation ting position, lifting the body weight up or by performing sports, repetitive mi- through both arms with extended elbows, T he most commonly recommended crotrauma having caused the instability. treatment for MDI is nonoperative, depressing the scapula) for the lower By the time the athlete presents to our with emphasis on rehabilitation and trapezius, latissimus dorsi, teres major, office, instability is usually present but activity modification.9,44,65 Surgery is re- pectoralis major and minor; rowing for might have started with only laxity. served for those patients who have failed the middle trapezius and rhomboids; and journal of orthopaedic & sports physical therapy | volume 39 | number 2 | february 2009 | 127
  5. 5. [ CLINICAL COMMENTARY ] maintaining the glenohumeral joint in a static position.77 Positions of rhythmic stabilization can be varied to address the patient’s directions of greatest weakness/ stability. These exercises are typically initiated in a supine position and include resisted external/internal rotation (ER/ IR) with the shoulder abducted 20° to 30°, flexion/extension with the shoulder flexed to 90°, and horizontal abduction/ Strengthening of the lower trapezius horizontal adduction with the shoulder Active range-of-motion exercise for muscle. external rotation. A towel is placed between the arm flexed to 90°. The exercises can prog- and the patient’s side to slightly abduct the shoulder ress into larger amount of flexion and so as to optimize blood perfusion to the rotator cuff push-ups with a “plus” (purposeful pro- abduction positions, and into upright and increase infraspinatus recruitment. traction of the scapula) for the serratus positions.14,77 anterior (progressing from wall push- Townsend et al72 measured rotator ups to push-ups on the floor as stability cuff and glenohumeral muscle recruit- increases).15,43,52 ment patterns via EMG for specific exer- Further, EMG studies of the periscapu- cises. Some of the optimal exercises they lar muscles indicate that prone arm raises identified overlap with those suggested with elbow extension are also beneficial, by Moseley et al.52 Scapular abduction in particularly with the arms placed at 90° the open-can position (thumb-up) best of abduction for recruitment of middle recruits the supraspinatus, anterior del- trapezius, and arms between 140° to 150° toid, and middle deltoid; press-downs of abduction for recruitment of lower tra- (from a sitting position, lifting body pezius ( ).18 In these positions, it is weight up through both arms with ex- Resisted shoulder external rotation using important to maintain the glenohumeral tended elbows, depressing the scapula) Thera-Band. joint in ER to minimize iatrogenic im- best recruit the lower fibers of the in- pingement of the supraspinatus against fraspinatus, teres minor, and subscapu- that the optimal position of the humerus the anterior acromion.14,24,61 An exercise laris; flexion of the shoulder recruits the is in approximately 30° of scapular ab- to progress from the prone position to anterior deltoid and coracobrachialis; duction to optimize the blood flow to the work on the periscapular musculature is and prone horizontal abduction with rotator cuff tendon.4,58 Also, the use of an to wrap Thera-Band around the patient’s ER best recruits the infraspinatus, teres object for the humerus to adduct against hands and have the patient maintain minor, and posterior deltoid.72 It should while performing these shoulder rota- tension through the Thera-Band as he/ be further noted that, while past EMG tion exercises has been shown to increase she alternately walks the hands up a wall studies found the empty-can (thumb- EMG signal amplitude of the infraspina- to maximal tolerated elevation. This en- down) position of scapular abduction to tus ( ).60 Once perfected courages scapular retraction, stabilizing be optimal for supraspinatus activation, with the humerus relatively at the side, the rotator cuff base as the patient works subsequent studies have shown that the these exercises can be progressed to per- in an overhead position.40 open-can position (thumb-up) not only formance in 90° of scapular abduction Stabilization exercises of the scapula equally or better recruits the supraspi- to minimize anterior glenohumeral liga- using manual resistance and isomet- natus8,13,35,60 but also protects against iat- ment strain with overhead throwing.11 ric exercises can be used to prepare the rogenic impingement of the rotator cuff In studies to examine the effects of periscapular muscles for the exercises under the anterior acromion.8,24,60 muscle fatigue,74,75 radiographs were listed above. With sufficient periscapular The following exercises may be includ- used to document glenohumeral me- stabilization, rehabilitation can subse- ed for rotator cuff muscles recruitment: chanics, showing that the humeral head quently address the rotator cuff. To initi- side-lying glenohumeral ER ( ) migrated superiorly at 45°, 90°, and 120° ate rotator cuff strengthening, rhythmic for infraspinatus,3 teres minor,3 and su- of abduction. This demonstrates the im- stabilization exercises (gently resisting praspinatus,13 and seated or standing portance of rotator cuff and periscapular antagonistic musculature in an alternat- resisted glenohumeral IR for activation stabilization. ing pattern)54 are used to initiate cocon- of subscapularis and pectoralis major.13 Once sufficient strength is noted in traction of the rotator cuff muscles while With these exercises it should be noted the periscapular, glenohumeral, and 128 | february 2009 | volume 39 | number 2 | journal of orthopaedic & sports physical therapy
  6. 6. rotator cuff muscle groups, functional training must begin in patterns recruit- ing all muscle groups together. Joint pro- prioceptive training is important for the unstable glenohumeral joint, as the joint receptors and stretch receptors in the ligaments surrounding the joint provide feedback for the contractile structures to maximize stability in unstable situa- tions.37 A proposed mechanism to aid in re-establishing the role of proprioception Two-handed overhead plyometric drill with a medicine ball. was described by Inman.30 His theory re- volved around the idea of subjecting the shoulder to certain motions and positions push-up on a tilt board or physioball, to promoting instability during treatment to walking push-up stepping up and down elicit a reflective muscular protective re- a step with alternating hands can also be sponse during unstable events. Diagonal utilized to improve dynamic stability as proprioceptive neuromuscular facilita- well as joint proprioception.14 tion (PNF) patterns can be used to this The use of a Bodyblade is very effec- effect in various positions with varying tive in gaining glenohumeral and scapu- resistance. Particularly the diagonal flex- lothoracic stability with the shoulder in Anterior and posterior views of a SAWA brace (Brace International, Georgia). This brace ion pattern 2 (D2F) recruiting middle tra- any position and is excellent for endur- provides stability with relatively good mobility. pezius, lower trapezius, posterior deltoid, ance training of rotator cuff muscles. The infraspinatus, supraspinatus, and teres Bodyblade is a long, slender portion of used, including plyometric training.14 minor.54 Perturbation training (rhyth- flexible plastic that the patient vibrates Plyometrics allow the muscles around the mic stabilization) can be used both in in quick oscillatory movements in par- glenohumeral joint to respond to a quick non–weight-bearing and weight-bearing ticular positions or throughout shoulder stretch, protect the joint, and rapidly re- progressions for proprioceptive training range of motion (ROM) to encourage verse direction to produce the appropriate at a variety of glenohumeral angles,3,30 maximal cocontraction of the rotator cuff action, with rapid contraction of the pre- progressing from known to random pat- and periscapular muscles.10 Exercise pro- viously stretched muscle.28 Plyometrics terns, from resistance applied proximal gression with the Bodyblade begins with can be progressed from 2- to 1-handed to distal to the glenohumeral joint, and the glenohumeral joint in relative neutral drills, drills below 90° to overhead drills, from submaximal to maximal efforts.14 (maintaining a towel roll or bolster to and small to larger weight. Rebounders Weight-bearing activity also generates abduct the shoulder), with oscillations in ( ) can be used to initiate throw- specific patterns of cocontraction of the ER/IR. With the elbow extended, oscil- ing patterns for patients, beginning with rotator cuff, glenohumeral muscles, and lations next move medial to lateral, with sagittal plane 2-handed, to transverse periscapular stabilizers, as this is how the shoulder flexed and maintained at plane 2-handed, to 1-handed throw. It these muscles are used in many activities angles between 45° and 90°, then prog- must be stressed that these programs are of daily life.14,28,30,36 Wall wash exercises ress into positions of scapular abduction individually based on the level of activ- in clockwise/counterclockwise circles maintained at angles of 45° to 90°. An- ity desired and the patient’s goals, and and figure-eight patterns, while main- other progression is to redirect the angle appropriateness given shoulder stability taining pressure through a towel or ball, of oscillations inferior to superior. Once achieved with previous strengthening. are a good initiation of weight-bearing satisfactory glenohumeral and scapu- We advocate the use of a SAWA brace exercise for dynamic stability.40 Other lothoracic mechanics can be maintained, (Brace International, Atlanta, GA) in ad- weight-bearing exercises include hand- these exercises can be progressed to mov- dition to therapy in our athletic popu- walking on a treadmill, and kneeling with ing through these angles of flexion and lation or in those individuals who are 1 or both hands on the Profitter (movable, scapular abduction, then into overhead very active. This allows participation in unstable surface) and moving the arms positions. Most difficult is mimicking the sports with a higher amount of stability in angles varying from flexion/extension, diagonal PNF patterns.10 ( ). scapular abduction, to horizontal ab- For those patients looking to return Rowe and Zarins65 reported that the duction/adduction.40 Progression from to sports or other higher-level activ- majority of their patients with atraumatic wall push-up, to standard push-up, to ity, sport and activity training should be instability did well with physical therapy journal of orthopaedic & sports physical therapy | volume 39 | number 2 | february 2009 | 129
  7. 7. [ CLINICAL COMMENTARY ] in a short-term follow-up. Burkhead and Rockwood9 showed that when using a conservative rehabilitation program for atraumatic shoulder instability, 66 (86%) of their patients obtained good to excel- lent results. In contrast to these encour- aging results, Tillander et al71 reported that less than 50% of their 20 patients were satisfied with rehabilitation alone. Misamore et al,50 in a study using a 7- to 10-year follow-up, showed that only 17 of their 57 patients had satisfactory out- comes from nonoperative measures. Patient education, activity modifi- Posterior open capsular shift. A cation, and patience from all involved longitudinal incision is made in line with the parties are needed to obtain the desired infraspinatus fibers to the capsular level. results. An extensive course of physical therapy of 6 months may provide greater around the humeral neck. This resembles than 90% satisfactory results. Only after a sideways T. Superior advancement with failure of an extensive course of reha- the inferior flap is made until the laxity is bilitation should surgical intervention be eliminated from the inferior pouch. The entertained. superior flap is then brought down over the inferior flap and laterally. Sutures are used to secure the repair in this new posi- tion in a “vest over pants” fashion ( urgical intervention for MDI 8). Reattachment of the subscapularis is Anterior open capsular shift. Top drawing requires the difficult task of decreas- depicts line of capsular incision as a sideways “T.” then performed, followed by closure of ing abnormal translation of the hu- Bottom drawing shows capsular closure with a the skin. The results are satisfactory in meral head while retaining adequate superior shift of the inferior capsule. 80% to 95% of patients treated in this mobility. A thorough physical exam of fashion, with recurrence rates less than the shoulder under anesthesia provides 10%.21,38 the surgeon the opportunity to exam- Neer and Foster53 first reported on per- Wirth et al78 have described an al- ine the extent of the instability. An open forming an inferior capsular shift proce- ternative technique that uses a vertical capsular shift has been used with good dure in 1980. In their report, however, 26 incision through the mid portion of the success as the procedure of choice to re- of their 29 patients had a traumatic event capsule. Using this technique he reports duce the amount of capsular volume. The and 17 were labeled as having ligamen- a recurrence rate of 6%. A glenoid-based amount of shift and tension can be seen tous laxity. Patients were followed for 1 shift was performed by Altchek et al,2 and felt directly to achieve the desired ef- year, with 1 having unsatisfactory results with recurrence rates of approximately fect. There can be a large amount of pain and 3 having axillary nerve injuries. Nine 10%. A biomechanical study in cadav- postsurgery if the combined anterior and patients returned to competitive sports. eric specimens showed that a glenoid posterior approach is used. Arthroscopic The focus of the surgical procedure was based shift (the vertical incision made capsular plication has demonstrated on tightening the glenohumeral liga- near the glenoid) produced less posterior equivalent success to the open procedure ments using an inferior-to-superior ad- translation of the humeral head than a with less postoperative pain, no disrup- vancement (“shift”) of the capsule.69 The humeral-based capsular shift, but the tion of the subscapularis muscle, and less basic surgical technique through a del- latter resulted in a greater reduction in cosmetic scarring; but this technique topectoral approach involves detaching capsular volume.16 involves a learning curve. Also, long- the subscapularis tendon. Once detached When the primary direction of insta- term results from arthroscopic capsular from the humerus, careful dissection al- bility is in the posterior direction, a pos- plication surgery are not available. This lows separation of the subscapularis from terior approach is taken and a capsular manuscript will not discuss arthroscopic the capsule. A horizontal capsular incision shift is also performed. The capsular shift thermal capsulorrhaphy due to poor re- is made from the glenoid to the humeral from inferior to superior is performed to sults obtained with this procedure. neck, and a vertical incision is then made tighten the capsular structures ( ). 130 | february 2009 | volume 39 | number 2 | journal of orthopaedic & sports physical therapy
  8. 8. A soft-tissue penetrator is used to A crescent soft-tissue penetrator is used Arthroscopic capsular plication for the capture the capsule and labrum. Note that there is to capture the capsule and labrum. treatment of instability. Note the reduction in space considerable space in between the humeral head between the humerus and glenoid after the capsular superiorly and the glenoid labrum inferiorly. plication, compared to . through the capsule and labrum ( - However, this presents a predicament: al- URE 10). A monofilament suture is used surgical procedure, the surgical technique though the outcomes appear more than to pass the #2 braided nonabsorbable used, and the quality of the tissue found reasonable in regard to recurrence rates, suture through the tissue. This suture at the time of surgery. Initially, a period of instability and laxity may still be present should capture the more inferior cap- immobilization of approximately 2 weeks in this population even after the surgical sule, as well as the labrum slightly more in a sling is advocated. Our patients wear procedure. superior. This process is repeated while an abduction brace in neutral for 4 to moving superiorly, achieving the de- 6 weeks to protect the repair, including sired tightness ( ). Then, during sleep. As with any shoulder sur- Arthroscopic management has evolved to a posterior capsular shift is performed in gery, ROM of the elbow, wrist, and hand the point that results are comparable to a similar fashion, significantly reducing is encouraged from day 1. Cryotherapy is open procedures, with less perioperative the volume of the capsule.69 The poste- recommended for 20 minutes every 2 to risk. This is currently the authors’ pre- rior shift begins at about 7 o’clock and 3 hours postsurgically for the first week ferred surgical technique. The goals of moves superiorly ending at about the 9 and after every therapy session. We often surgery are similar: identify the directions o’clock position. This latter part of the recommend gentle, small-arc pendulum of instability and reduce capsular volume procedure is done as needed, depending exercises from day 1. to restore stability to the shoulder. on the directions of initial instability, as Physical therapy may begin earlier Surgical options include placing an- well as the amount of stability obtained than, for instance, after rotator cuff re- chors along the glenoid rim and shifting after anterior capsular shift. pair because the quality of rotator cuff the capsule using stitches, capsular pli- Rotator interval closure may be per- tissue is usually good and, therefore, cation techniques that involve gathering formed if the sulcus sign of 2+ does not does not present a problem with early the capsule and bringing it to the labrum, improve when tested with the arm in ROM. During this phase of treatment, and thermal capsulorrhaphy (which is ER. A curve-shuttling device or soft- ROM is restricted to prevent excessive falling out of favor due to poor results). tissue penetrator is inserted through the strain to the repaired tissue, typically for These procedures can be combined with anterosuperior cannula and a #1 mono- 6 weeks. For the first 2 weeks, passive a rotator interval closure.49 filament suture is advanced superior to ROM (PROM) and active assisted ROM Arthroscopic treatment of MDI in- the subscapularis tendon. A penetrating (AAROM) should be limited to neutral volves first a standard diagnostic ar- instrument is passed just anterior to the for ER, 30° of scapular abduction, and throscopic examination, followed by subscapularis tendon and the suture is 45° of flexion.77 Isometric exercises for abrasion of the capsule in preparation retrieved through the anterosuperior the scapulothoracic musculature are for capsular plication. The next step in- portal. A knot is tied outside the capsule initiated during the first week postsur- volves performing a multipleated plica- blindly. A second suture may be passed gery, followed by isometric exercises for tion from as low as the 5 o’clock position lateral to the first suture if further closure the glenohumeral musculature at week for an anterior capsular shift. A suture is needed. 2, with all isometrics being performed is passed with or without a transglenoid at submaximal intensities with no to anchor through the capsule, making minimal pain.77 Also, at 2 weeks post- sure to grab capsular tissue from the in- The postoperative rehabilitation of the operatively, AAROM can be performed ferior aspect of the gutter. A soft-tissue surgically corrected multidirectional un- with shoulder flexion to 60°, ER to 5° to penetrator is used to make the passes stable shoulder is tailored based on the 10°, and IR to 45°, unless an open repair journal of orthopaedic & sports physical therapy | volume 39 | number 2 | february 2009 | 131
  9. 9. [ CLINICAL COMMENTARY ] was performed, in which case we delay the nonoperative section. The goal is to tcheck et al,2 reported 90% satisfactory AAROM for IR until the sixth week. achieve normal scapulothoracic and gle- results in their studies. Similarly, Cooper PROM can be increased at 4 weeks to a nohumeral mechanics and good muscle and colleagues12 obtained 91% satisfac- maximum of 90° for flexion and scapular endurance.77 Eccentric exercises should be tory results, and Pollock et al57 had 96%. abduction, and ER/IR performed at 20° performed by the twelfth week. Once the Based on these studies and a few oth- scapular abduction to tolerance.77 Upper patient has full strength of the periscap- ers, postsurgical outcomes appear to be extremity rhythmic stabilization exercis- ular muscles, rotator cuff, and shoulder promising. But the population used in es at glenohumeral angles less than 60° muscles, as well as good scapulothoracic these studies was rather heterogeneous, of elevation are initiated by the fourth rhythm with full ROM, advanced train- without a strict definition or criteria for week, including ER and IR.27 During ing can begin. inclusion; therefore, results should be in- these first 4 weeks, flexibility of the tho- In weeks 14 to 20, strength and en- terpreted with caution. racic and lumbar areas is also addressed durance are improved, with continued Based on the work of Misamore and therapy implemented.27 Once the progression of therapeutic exercise.77 and colleagues,50 90% of their patients glenohumeral motion has reached ap- Functional activity is gradually initiated, achieved good results and were able to proximately 90° of elevation, progression and plyometric training may begin. Golf- perform activities of daily living post- to weight-bearing exercises is instituted, ers may initiate swings around weeks 14 surgery. Of those, 66% were able to using the progressions mentioned in the to 16, and athletes may begin interval return to sporting activities, but only nonoperative section.29 programs at week 18. Beyond week 20, about 50% were able to return to high Weeks 5 and 6 are dedicated to re- aggressive strengthening may take place, level of participation. It is therefore storing further ROM. Shoulder flexion as well as advanced PNF drills, plyo- worth advising patients in the high-level ideally should reach 135° to 140° by the metrics, and full sports activity—except athletic population that the results are end of week 6.77 It is critical to recognize for throwing, which is allowed at 8 to 9 not as good compared to the general that to progress with ROM, the absence months postoperatively.77 population.22 of pain and apprehension is required. In the high-velocity throwing athlete, Hamada et al25 treated 34 shoulders Scapular protraction and retraction ex- this may present as a career-ending event with an inferior capsular shift obtaining ercises are emphasized. Light resistance due to ER ROM limitations after reha- 85% satisfactory outcome. They, how- can be added to ER and IR active ROM bilitation. Frequent follow-up visits with ever, had a recurrence rate of 50% in the (AROM) for rotator cuff strengthening the surgeon should be made to monitor 12 voluntary dislocators compared to 14% using Thera-Band.77 We recommend therapy progression. In our practice we recurrence rate in the other 22 patients. working through smaller arcs of mo- see our patients within 10 days following When performing revision surgery for tion to begin with, and progressing to the operation, at which point stitches are MDI, Zabinsky et al80 reported that at an larger arcs over the following 4 weeks removed and the incisions inspected. The average 61.5-month follow-up only 39% to protect the repair and allow gradual patient then returns at 6 weeks, followed of patients achieved good or excellent re- adaptation. by visits at 3, 6, and 12 months postsur- sults, compared to 78% achieving good From weeks 6 to 14 we hope to achieve gically. The goal for these patients is to results for revision surgery for anterior full and painless ROM, restore strength, return to their normal daily functions, instability. and allow return to some daily activity. including work, sports, and high-level In weeks 7 and 8 flexion and scapular activity. abduction ROM are increased to 180°, ER to 80°, and IR to 70° to 75°.76 ER/IR ith a better understanding isotonic exercises are performed at angles of the pathological process in- up to 90° abduction. After the sixth week, volved with MDI, we are now A great number of surgical and strengthening is initiated with concentric nonsurgical failures arise as a con- able to more successfully treat this popu- exercises, as described in the nonopera- sequence of incorrect diagnosis. lation. Nonoperative treatment is the first tive section (periscapular stabilization, Failure to address the other components option to treat a patient with MDI. When rotator cuff strengthening). Light PNF of MDI can result in a substandard out- nonsurgical treatment fails, then surgery techniques may be used at this time. come. Nonoperative treatment failures should be considered. Free weights are implemented once larg- can also present from inadequate reha- Advances in technology and im- er arcs of ROM have been achieved.17,66 bilitation of the supporting periscapular provements in arthroscopic surgical All strengthening, including that of the and shoulder musculature. techniques have made this surgical ap- periscapular and rotator cuff muscles, With open surgical treatment for proach at least equal, if not better than, progresses, as mentioned previously, in MDI, Neer and Foster,53 and then Al- open surgical procedures. Understand- 132 | february 2009 | volume 39 | number 2 | journal of orthopaedic & sports physical therapy
  10. 10. ing the pathoanatomy present in each orthogonal polarization spectral imaging during Arthrosc Rev. 2004;12:127-134. arthroscopy of the shoulder. J Bone Joint Surg Flatow EL, Warner JJP. Instructional course patient helps to address all pathologies Am. 2003;85-A:475-480. lectures, the American Academy of orthopedic involved at the time of surgery. The goals Bigliani LU, Kurzweil PR, Schwartzbach CC, Surgeons - Instability of the shoulder: Complex of arthroscopic and open techniques Wolfe IN, Flatow EL. Inferior capsular shift pro- problems and failed repairs. Part 1. Relevant involve restoration of capsular tension. cedure for anterior-inferior shoulder instability biomechanics, multidirectional instability and in athletes. Am J Sports Med. 1994;22:578-584. severe loss of glenoid and humeral bone. J Bone It is the authors’ preferred method to Bowen MK, Warren RF. 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