Multidirectional Laxity Research Articles

National Collegiate Athletic Association Swimmers With Glenohumeral Multidirectional Laxity Have an Increased Glenohumeral Joint Range of Motion Profile.

Adaptations in glenohumeral joint laxity and range of motion (ROM) are prevalent in competitive swimmers. Increased glenohumeral laxity in swimmers has been found to exist in multiple directions. However, it is unclear if swimmers with multidirectional laxity (MDL) possess altered glenohumeral ROM compared with swimmers without MDL. The purpose of this study was to compare the glenohumeral ROM characteristics of external rotation (ER), internal rotation (IR), total arc of motion (ER + IR), and total arc of motion ratio (ER/IR) between swimmers with MDL and without MDL. Our secondary objective was to investigate the effect of MDL on self-reported pain and function. Observational study. Twenty-nine NCAA Division I swimmers (females: 15 and males: 14; age 19.5 [1.2]y; body mass index 23.9 [2.0]km/m2) participated in a preseason physical assessment including measures of glenohumeral ROM and joint laxity. These measures were used to determine the presence or absence of MDL for both shoulders of each participant. Glenohumeral ROM characteristics were compared between shoulders with MDL and shoulders without MDL with independent t tests. Self-reported pain and function scores were recorded biweekly across the season with a modified Kerlan-Jobe Orthopedic Clinic questionnaire. The seasonal average Kerlan-Jobe Orthopedic Clinic questionnaire scores were compared between swimmers with MDL and swimmers without MDL with analysis of variance, with factors of sex and MDL status. Shoulders with MDL possessed increased glenohumeral IR (P < .001; effect size: 0.65) and total arc of motion (P < .004; effect size: 0.45) compared with shoulders without MDL. There were no differences in ER. There was no difference in self-reported pain and function between groups. Shoulders with MDL possess increased glenohumeral IR and total arc of motion compared with shoulders without MDL. The presence of MDL may not affect self-reported pain and function in competitive swimmers.

MEAN 6 YEAR CLINICAL OUTCOMES, SURVIVORSHIP, AND RETURN TO SPORTS AFTER ARTHROSCOPIC CAPSULAR REPAIR WITH SUTURE ANCHORS FOR ADOLESCENT MULTIDIRECTIONAL SHOULDER INSTABILITY

Background:Multidirectional shoulder instability (MDI) refractory to rehabilitation can be treated with arthroscopic capsulolabral reconstruction with suture anchors. No studies have reported on outcomes or examined the risk factors that may contribute to poor outcomes in adolescent athletes.Hypothesis/Purpose:To identify risk factors for surgical failure by comparing anatomic, clinical, and demographic variables in adolescents who underwent surgical intervention for MDI.Methods:All patients undergoing arthroscopic shoulder surgery at one institution between January 2009 and April 2017 were reviewed. Patients >20 years old at presentation were excluded. Multidirectional instability was defined by positive drive-through sign on arthroscopy plus positive sulcus sign and/or multidirectional laxity on anterior and posterior drawer testing while under anesthesia. Two-year minimum follow-up was required, but those whose treatment failed earlier were included for reporting purposes. Demographics and intraoperative findings were recorded, as were Single Assessment Numeric Evaluation (SANE) scoring, Pediatric and Adolescent Shoulder Survey (PASS), and the short version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) results.Results:Eighty adolescents (88 shoulders) were identified for having undergone surgical treatment of MDI. Of these 80 patients, 42 (50 shoulders; 31 female, 19 male) were available at a minimum of 2-year follow-up. Mean follow-up was 6.3 years (range, 2.8-10.2 years). Thirteen (26.0%) shoulders experienced surgical failure defined by recurrence of subluxation and instability, all of which underwent re-operation. Time to re-operation occurred at a mean of 1.9 years (range, 0.8-3.2). Our cohort had an overall survivorship of 96% at 1 year after surgery and 76% at 3 years. None of the anatomic, clinical, or demographic variables tested, or the presence of generalized ligamentous laxity, were correlated with subjective outcomes or re-operation. Number of anchors used was not different between those that failed and those that did not fail. Patients reported a mean SANE score of 83.3, PASS score of 85.0, and QuickDASH score of 6.8. Return to prior level of sport (RTS) occurred in 56% of patients.Conclusion:Multidirectional shoulder instability is a complex disorder that can be challenging to treat. Adolescent MDI that is refractory to non-surgical management appears to have long-term outcomes after surgical intervention that are comparable to adolescent patients with unidirectional instability. In patients who do experience failure of capsulorraphy, we show that failure will most likely occur within 3 years of the index surgical treatment.Figure 1.2.Representative case demonstrating presence of drive-through sign of the glenohumeral joint as viewed through the posterior portal at the beginning of case and subsequent absence of drive-through sign after adequate capsular repair had been achieved

The contralateral knee is a good predictor for determining normal knee stability: a cadaveric study.

The goal is to evaluate contralateral knee joint laxity and ascertain whether or not contralateral symmetry is observable. Secondary, a validation of a knee laxity testing rig is provided. Seven pairs of cadaveric knee specimens have been tested under passive conditions with and without external loads, involving a varus/valgus and an external/internal rotational torque and an anteroposterior shear force. Through the range of motion, the width of the varus/valgus laxity, internal/external laxity and anterior/posterior laxity for the medial and lateral compartment show no significant differences between left and right leg. These findings allow us to validate the setup, especially for relative values of laxity based on anatomical measures and knee joint biomechanics. A multidirectional laxity symmetry has been demonstrated for the intact knee and its contralateral knee in passive conditions as in an anesthetized patient. The passive laxity evaluation setup has been validated. Our work furthermore demonstrated a pronounced difference in anteroposterior mobility between the medial and lateral compartment of the knee, with a more stable medial side and more mobile lateral side. The contralateral knee can be used as reference for determining optimal knee laxity peri-operatively in total knee replacement and ligament reconstruction. Level IV, Case series.

Indication and technique for arthroscopic stabilization of anterior shoulder instability with multidirectional laxity

AbstractAs concomitant hyperlaxity has been identified as an independent risk factor for failure following anterior shoulder stabilization, the treatment of this special pathology remains challenging. There is a broad consensus that a clear differentiation to multidirectional instability and isolated anteroinferior instability should be ensured to avoid unsatisfactory outcomes. Typical features of this patient collective include positive clinical tests for anteroinferior instability and multidirectional shoulder hyperlaxity, findings of an anterior labral lesion and general capsular redundancy in the radiologic assessment, while tests for posterior instability are negative. Surgical treatment should consist of an anteroinferior capsulolabroplasty with concomitant posteroinferior plication to reduce pathological capsular volume. Although there is a lack of clinical evidence, biomechanical investigations suggest that a four-anchor construct with three anterior anchors and one posteroinferior anchor may be sufficient to restore glenohumeral stability. This surgical approach is presented and discussed in the current article.

Clinical Outcomes, Survivorship, and Return to Sport After Arthroscopic Capsular Repair With Suture Anchors for Adolescent Multidirectional Shoulder Instability: Results at 6-Year Follow-up.

Background:Multidirectional shoulder instability (MDI) refractory to rehabilitation can be treated with arthroscopic capsulolabral reconstruction with suture anchors. To the best of our knowledge, no studies have reported on outcomes or examined the risk factors that contribute to poor outcomes in adolescent athletes.Purpose:To identify risk factors for surgical failure by comparing anatomic, clinical, and demographic variables in adolescents who underwent intervention for MDI.Study Design:Case series; Level of evidence, 4.Methods:All patients 20 years or younger who underwent arthroscopic shoulder surgery at a single institution between January 2009 and April 2017 were evaluated. MDI was defined by positive drive-through sign on arthroscopy plus positive sulcus sign and/or multidirectional laxity on anterior and posterior drawer tests while under anesthesia. A 2-year minimum follow-up was required, but those whose treatment failed earlier were also included. Demographic characteristics and intraoperative findings were recorded, as were scores on the Single Assessment Numeric Evaluation (SANE), Pediatric and Adolescent Shoulder Survey (PASS), and short version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH).Results:Overall, 42 adolescents (50 shoulders; 31 female, 19 male) were identified as having undergone surgical treatment for MDI with minimum 2-year follow-up or failure. The mean follow-up period was 6.3 years (range, 2.8-10.2 years). Surgical failure, defined as recurrence of subluxation and instability, was noted in 13 (26.0%) shoulders; all underwent reoperation at a mean of 1.9 years (range, 0.8-3.2 years). None of the anatomic, clinical, or demographic variables tested, or the presence of generalized ligamentous laxity, was associated with subjective outcomes or reoperation. Number of anchors used was not different between shoulders that failed and those that did not fail. Patients reported a mean SANE score of 83.3, PASS score of 85.0, and QuickDASH score of 6.8. Return to prior level of sport occurred in 56% of patients.Conclusion:Adolescent MDI refractory to nonsurgical management appeared to have long-term outcomes after surgical intervention that were comparable with outcomes of adolescent patients with unidirectional instability. In patients who experienced failure of capsulorrhaphy, results showed that failure most likely occurred within 3 years of the index surgical treatment.

Traitement des grands collapsus de la colonne du pouce après trapézectomie à un recul minimum de 2 ans

Trapezectomy represents the gold standard for treatment of painful peritrapezial osteoarthritis resistant to the medical treatment. A well-know complication is the collapse of the space of trapeziectomy despite realization of a ligamentoplasty or suspensioplasty. It can causes at long term scaphometacarpal osteoarthritis, loss of strength, adductus deformation and pain. The aim is to report our experience of treatment the major collapse of the thumb after trapezectomy and the results at minimum follow-up of 2 years. We reviewed 15 patients operated by a senior surgeon after a minimum follow up of 2 years after the salvage procedure. Clinical assessment compare pain by EVA scale, joint amplitude, kapandji opposition score, QuickDash score, satisfaction, complications, revisions. Radiological assessment compares the proximal migration and subluxation of M1, the height of the trapezial void, osteoarthritis scaphometacarpal. The treatment consist of the release of the first metacarpal, ligamentoplasty by Brunelli associated tendon interposition, palmar capsulodesis and temporary intermetacarpal and metacarpophalangeal fixation by a Kirschner. Between January 2013 to January 2016 we treated 15 patients for major collapse of the thumb after trapezectomy concerning 14 women and 1 man with a mean age 58 years (47–93). The mean follow-up was 42 months (24–60). All of them were operated for osteoarthritis peritrapezal at mean 6 years ago (1–8) in another center by trapezectomy alone or PLA interposition. Fifteen patients had pain with a mean EVA at 4 10 (2–8). Grip strength and key pinch was mean 8 kg (3–14). The mean joint mobility sector was for the metacarpophalangeal 60° (50–70°) and 80° (70–90°) for the interphalangeal. The Kapandji score was for all 10 10. All patient did not forget this thumb and had an attitude of protection towards him. The mean QuickDash score was 35 (20–50). Concerning radiological assessment the mean space height was 1,2 mm (0,8–1,2). Trapezometacarpal arthroplasty have revolutionized postoperative rhizarthrosis for rapid recovery and shorter postoperative immobilization. The trapeziectomy stay an indication of choice in case of dysplasic trapezium, multidirectional laxity of the MPA and STT involvement. These poor clinical and radiographic results post-trapeziectomy with major collapse are not acceptable in our patients who have a longer life expectancy in good health. This procedure helps to treat pain significantly despite mixed radiographic results.

Electrothermal arthroscopic capsulorrhaphy: old technology, new evidence. A multicenter randomized clinical trial

Radiofrequency technology for shoulder instability was rapidly adopted despite limited clinical evidence and a poor understanding of its indications. Reports of serious adverse events followed, leading to its abandonment. This paper presents findings from a multicenter randomized clinical trial evaluating the safety and efficacy of electrothermal arthroscopic capsulorrhaphy (ETAC) compared with open inferior capsular shift (ICS) and reviews the role of randomized trials in adopting new technology. Patients (>14years) diagnosed with multidirectional instability or multidirectional laxity with anteroinferior instability and failed nonoperative treatment were enrolled. Patients with bone lesions or labral, biceps anchor, or full-thickness rotator cuff tears were excluded intraoperatively. Outcomes included Western Ontario Shoulder Instability Index, function and recurrent instability at 2 years postoperatively, and surgical times. Fifty-four subjects (mean age, 23years; 37 women) were randomized to ETAC (n=28) or open ICS (n=26). The groups were comparable at baseline, except for external rotation at the side. At 2 years postoperatively, there were no statistically or clinically significant differences between groups for the Western Ontario Shoulder Instability Index (P=.71), American Shoulder and Elbow Surgeons score (P=.43), Constant score (P=.43), and active range of motion. Recurrent instability was not statistically different (ETAC,2; open,4; P=.41). ETAC (23minutes) was significantly shorter than open ICS (59minutes) (P<.01) surgery. Three subjects (1 ETAC, 2 open) had stiff shoulders. At 2 years postoperatively, quality of life and functional outcomes between groups were not clinically different. ETAC had fewer complications and episodes of recurrence compared with open surgery. This evidence reinforces the need to critically evaluate new technology before widespread clinical use.

Simultaneous 3D Assessment of Glenohumeral Shape, Humeral Head Centering, and Scapular Positioning in Atraumatic Shoulder Instability

Background Success rates in the treatment of atraumatic shoulder instability differ, and in vivo identification of the individual insufficient stabilizers is difficult. Hypothesis Atraumatic shoulder instability is an inhomogeneous entity with varying alterations of the active and passive stabilizers. This might be a reason for inferior treatment results. Study Design Case control study; Level of evidence, 3. Methods Shoulders of 28 healthy volunteers and both shoulders of 14 patients with atraumatic instability and multidirectional laxity were examined in different arm positions using open magnetic resonance imaging. Three-dimensional postprocessing techniques were applied to determine 3D glenoid size and retroversion, radius of the humeral head, and curvature of the glenoid. The results of static stabilizers were compared with those of glenohumeral and scapular positioning in the same patients for identification of the individual insufficient stabilizers. Results The atraumatic unstable shoulders showed an increased mean retroversion on both sides, the difference being significant on the affected side (9.4° ± 4.8° vs healthy 3.9° ± 1.3°; P < .05) with a range of 2.6° to 16.6°. The curvature analysis demonstrated a pronounced flatness of the glenoid with a significantly increased mean radius (103.8 mm vs healthy 41.7 mm). The extent of these changes varied widely among patients. Comparison of the static stabilizers with glenohumeral and scapular positioning revealed that isolated changes of the active stabilizers exist in some patients, whereas no isolated changes of passive stabilizers were found. Conclusion All active and passive stabilizers need to be analyzed in patients with atraumatic instability because the magnitude of alteration varied widely among individuals. Different combinations of alterations of the stabilizers were found. The presented technique allows for in vivo identification of the specific alterations. This is necessary for a better understanding of individual pathomechanics and for initiating a specific causal treatment.

Arthroscopic capsulo-labral repair and refixation with Mitek anchor in anterior shoulder instability

From May 1992 to September 1995, 38 patients with recurrent anterior shoulder instability underwent arthroscopic stabilization. The arthroscopic stabilization was performed by capsular shifting and labral refixation using Mitek anchors, based on the Wolf procedure. Immediately after operation active assisted shoulder mobilization was initiated (elevation 60 degrees, external rotation 20 degrees less than contralateral shoulder). After a mean follow-up of 24 months (12-42 months) 30 patients were evaluated by means of the Rowe Score. Excellent and good results were achieved in 90% (n = 27) of patients and 80% had no restriction in sports activities. In 4 of the patients (13%) redislocation occurred. Analysis of the recurrence revealed no adequate trauma in two patients with preoperative multidirectional laxity. One had a trauma and the fourth showed no compliance in the early postoperative period. Compared to the open Bankart operation the described procedure shows a slightly higher rate of redislocations. However, the approach is less invasive and the subscapularis tendon with its proprioception remains intact.

Poster 95: Ultrasound-Guided Aspiration of a Right Shoulder Spinoglenoid Notch Cyst: A Case Report

Setting: Outpatient clinic. Patient: A 35-year-old man with right shoulder pain. Case Description: The patient presented with a 6-week history of achy, nonradiating, posterior right shoulder pain. The pain primarily occurred with running and was limiting his training for an upcoming triathlon. Physical examination demonstrated mild infraspinatus atrophy, 3/5 strength with external rotation, and multidirectional laxity, which was most pronounced posteriorly at 3+. An ultrasound examination of the right shoulder demonstrated a large, well-defined 2.4×1.4×2.4cm simple cyst located in the spinoglenoid notch that deformed the overlying infraspinatus muscle. The cyst appeared to be arising from the posterior glenohumeral joint. Electromyography showed an acute to subacute right suprascapular neuropathy distal to the branch to the supraspinatus. Because the patient was hoping to participate in a triathlon in 1.5 weeks, it was decided to attempt to aspirate the cyst. Therefore, using ultrasound guidance, an 18-gauge spinal needle was advanced from a lateral-to-medial approach and penetrated the cyst. Aspiration produced 3.5mL of typical ganglionic fluid, which resulted in an approximately 50% reduction in the size of the cyst. Assessment/Results: The patient was able to complete the triathlon and was not limited by shoulder pain. Magnetic resonance imaging was performed following the triathlon and showed a 2.5×0.9cm lobulated ganglion cyst in the spinoglenoid notch with a moderate-sized posterior labral tear. The patient subsequently underwent right shoulder arthroscopy with cyst decompression and posterior superior labral repair. Discussion: This case illustrates the use of musculoskeletal ultrasound for both diagnostic and interventional purposes in the shoulder. The use of ultrasound in the presented case helped to provide an accurate, timely diagnosis and treatment of a difficult clinical problem. Conclusions: Musculoskeletal ultrasound is a useful tool for both diagnostic and interventional purposes.

Shoulder Pain - Triathlon

HISTROTY: A 35-year-old male triathlete presented with a six-week history of right posterior shoulder pain and weakness. He had originally injured his shoulder while reaching behind his head to elevate the head-rest on a car seat. At that time, he experienced the sudden onset of posterior shoulder pain, which has continued with minimal improvement. He has been training for an upcoming triathlon and notices the pain most when running. He is relatively pain-free with cycling and swimming, though he feels the shoulder is weak during swimming. He has also noted profound weakness with external rotation of the right shoulder during daily activities. He denies previous shoulder problems, numbness/tingling, or other weakness in the right upper limb. PHYSICAL EXAMINATION: Slight infraspinatus atrophy. Mild tenderness over the posterior glenohumeral joint. Shoulder motion was normal and non-provocative. Moderate (3/5) weakness with resisted external rotation. Negative Hawkins Neer's, O'Brien's, Speed's, and Scarf tests. Negative Spurling's maneuver. Multidirectional laxity present in the shoulders bilaterally. Neurovascular examination was normal. DIFFERENTIAL DIAGNOSIS: Spinoglenoid notch cyst (secondary to labral tear) causing partial suprascapular neuropathy Infraspinatus tear Cervical radiculopathy Parsonage Turner Syndrome/Brachial plexopathy TEST AND RESULTS: Ultrasound of right shoulder: -Moderate spinoglenoid notch cyst deforming the infraspinatus. No evidence of rotator cuff tear. EMG: -Subacute right suprascapular neuropathy distal to the branch to the supraspinatus, with minimal uncompensated denervation. MRI (post-triathlon): -Moderate-sized posterior labral tear with a small adjacent paralabral cyst. 2.5 × 0.9 cm lobulated ganglion cyst in the spinoglenoid notch with mild edema along the anterior belly of the infraspinatus muscle. FINAL WORKING DIAGNOSIS: Right posterior shoulder spinoglenoid notch cyst (secondary to posterior labral tear) with suprascapular neuropathy. TREATMENT AND OUTCOMES: Ultrasound-guided aspiration of right shoulder spinoglenoid notch cyst for symptomatic relief prior to triathlon. Subsequent right shoulder arthroscopic cyst decompression with posterior superior labral repair (after triathlon).

A multi-centre randomized controlled trial comparing electrothermal arthroscopic capsulorrhaphy versus open inferior capsular shift for patients with shoulder instability: protocol implementation and interim performance: lessons learned from conducting a multi-centre RCT [ISRCTN68224911; NCT00251160

BackgroundThe shoulder is the most frequently dislocated joint in the body. Multiple causes and pathologies account for the various types of shoulder instability. Multi-directional instability (MDI) and multi-directional laxity with antero-inferior instability (MDL-AII) are similar in pathology, less common and more difficult to treat. These instabilities are caused by ligamentous capsular redundancy. When non-operative management fails for these patients, quality of life is significantly impaired and surgical treatment is required to tighten the ligaments and joint capsule. The current reference (gold) standard treatment for MDI/MDL-AII is an open inferior capsular shift (ICS) surgical procedure. An alternative treatment involves arthroscopic thermal shrinkage of redundant capsular tissue to tighten the joint. However, there is a lack of scientific evidence to support the use of this technique called, electrothermal arthroscopic capsulorrhaphy (ETAC). This trial will compare the effectiveness of ETAC to open ICS in patients with MDI and MDL-AII, using patient-based quality of life outcome assessments.MethodsThis study is a multi-centre randomized clinical trial with a calculated sample size of 58 patients (p = 0.05, 80% power). Eligible patients are clinically diagnosed with MDI or MDL-AII and have failed standardized non-operative management. A diagnostic shoulder arthroscopy is performed to confirm eligibility, followed by intra-operative randomization to the ETAC or ICS surgical procedure. The primary outcome is the disease-specific quality of life questionnaire (Western Ontario Shoulder Instability Index), measured at baseline, 3, 6, 12 and 24 months. Secondary outcomes include shoulder-specific measures (American Shoulder and Elbow Surgeons Score and Constant Score). Other outcomes include recurrent instability, complications and operative time.The outcome measurements will be compared on an intention-to-treat basis, using two-sample independent t-tests to assess statistical significance. A Generalized Estimated Equations (GEE) analysis will determine whether there is an effect over time.DiscussionThis ongoing trial has encountered unexpected operational and practical issues, including slow patient enrollment due to high intra-operative exclusion rates. However, the authors have a greater understanding of multi-directional laxity in the shoulder and anticipate the results of this trial will provide the medical community with the best scientific clinical evidence on the efficacy of ETAC compared to open ICS.

The effects of thermal capsulorrhaphy and rotator interval closure on multidirectional laxity in the glenohumeral joint: A cadaveric biomechanical study

Arthroscopic rotator interval closure has been advocated to supplement the stabilization provided by thermal capsulorrhaphy for glenohumeral instability. However, no basic science study has examined the separate and combined effects of thermal capsulorrhaphy and rotator interval closure on the multiplane laxity of the glenohumeral joint. The purpose of this study was to measure the effects of isolated and combined thermal capsulorrhaphy and rotator interval closure on anterior, posterior, and inferior glenohumeral joint laxity in a cadaveric model. Anatomic biomechanical study. Ten cadaveric shoulders were fixed to a biomechanical testing apparatus and 5.5 lb (25 N) of force was applied to the humeral head in anterior, posterior, and inferior directions in a random order. Translation was measured in each direction on the untreated specimen (U), after arthroscopic rotator interval closure (R), after thermal capsulorrhaphy (T), and after combined rotator interval closure and thermal capsulorrhaphy (RT) with a transducer attached to a computer via data acquisition software and A/D board. Values for anterior, posterior, and inferior translation were thus obtained for U, R, T, and RT. Average translations in the anterior direction for the U, R, T, and RT groups were 8.0 +/- 4.4 mm, 6.7 +/- 3.3 mm, 8.5 +/- 3.6 mm, and 7.8 +/- 2.2 mm, respectively. Average translations in the posterior direction were 6.9 +/- 3.3 mm (U), 5.9 +/- 3.4 mm (R), 7.9 +/- 4.7 mm (T), and 6.8 +/- 4.0 mm (RT). Average translations in the inferior plane were 4.9 +/- 4.7 mm (U), 3.6 +/- 3.7 mm (R), 3.7 +/- 3.3 mm (T), and 2.4 +/- 1.6 mm (RT). Rotator interval closure decreased anterior, posterior, and inferior translation by 17%, 15%, and 28%, respectively, versus the untreated subjects. Thermal capsulorrhaphy increased anterior and posterior translation by 5% and 13% and decreased inferior translation by 25% versus untreated subjects. Combined RT decreased anterior, posterior, and inferior translation by 4%, 2%, and 52%, respectively. Statistical analysis revealed that rotator interval closure significantly decreased laxity values in all planes, whereas thermal capsulorrhaphy did not significantly alter laxity values versus untreated subjects. Isolated rotator interval closure decreased glenohumeral laxity in all directions tested, particularly inferior translation. Thermal capsulorrhaphy actually increased anterior and posterior translation in these subjects while decreasing inferior translation. We believe the trends seen reflect the clinical efficacy of rotator interval closure in the treatment of multidirectional instability. This procedure has the potential to provide improved stability versus thermal capsulorrhaphy alone, and may be considered as a supplement to or substitute for thermal capsulorrhaphy in patients with multidirectional instability. When treating glenohumeral instability with arthroscopic techniques, rotator interval closure may enhance stability to a greater degree than thermal capsulorrhaphy without its associated risks.

(i) Surgical approaches for instability surgery of the shoulder

The appropriate surgical approach for shoulder instability is determined by the type of instability, the major direction of instability and the contributing pathology. The definition of successful instability surgery is no longer regarded as absence of recurrence of dislocation after treatment but the ability to return to full capacity at work and recreation with no restriction of motion, apprehension or pain. The treatment aim is anatomical repair with restoration of stability, motion, strength and function. The chosen surgical approach should allow access to address the underlying pathology, use anatomical planes and avoid damage or risk to neurovascular structures to ensure restoration of full function post-operatively. An anterior approach is most commonly used for treatment of shoulder instability, as antero-inferior post-traumatic instability is the most common type of instability. Anterior approaches may be used for antero-inferior and multidirectional instability as well as for posterior instability as part of multidirectional laxity. Pure posterior instability is best approached posteriorly. In recent years, arthroscopic approaches are used for all these types of instability. Viewing and working portals can be swapped for better view and access.

(i) Surgical approaches for instability surgery of the shoulder

<h2>Abstract</h2> The appropriate surgical approach for shoulder instability is determined by the type of instability, the major direction of instability and the contributing pathology. The definition of successful instability surgery is no longer regarded as absence of recurrence of dislocation after treatment but the ability to return to full capacity at work and recreation with no restriction of motion, apprehension or pain. The treatment aim is anatomical repair with restoration of stability, motion, strength and function. The chosen surgical approach should allow access to address the underlying pathology, use anatomical planes and avoid damage or risk to neurovascular structures to ensure restoration of full function post-operatively. An anterior approach is most commonly used for treatment of shoulder instability, as antero-inferior post-traumatic instability is the most common type of instability. Anterior approaches may be used for antero-inferior and multidirectional instability as well as for posterior instability as part of multidirectional laxity. Pure posterior instability is best approached posteriorly. In recent years, arthroscopic approaches are used for all these types of instability. Viewing and working portals can be swapped for better view and access.

Shoulder electromyography in multidirectional instability

We studied shoulder muscle activity in multidirectional instability (MDI) and multidirectional laxity (MDL) of the shoulder, our hypothesis being that altered muscle activity plays a role in their pathogenesis. Six muscles (supraspinatus, infraspinatus, subscapularis, anterior deltoid, middle deltoid, and posterior deltoid) were investigated by use of intramuscular dual fine-wire electrodes in 7 normal shoulders, 5 MDL shoulders, and 6 MDI shoulders. Each subject performed 5 types of exercise (rotation in neutral, 45° of abduction, 90° of abduction, flexion/extension, and abduction/adduction) on an isokinetic muscle dynamometer at two rates, 90°/s and 180°/s. After filtering, rectification, and smoothing, the electromyography signal was normalized by using the peak voltage of the movement cycle. In subjects with MDI, compared with normal subjects, activity patterns of the anterior deltoid were different during rotation in neutral and 90° of abduction, whereas those of the middle and posterior deltoid were different during rotation in 90° of abduction. In subjects with MDL, the posterior deltoid showed increased activity compared with normal subjects during adduction. Activity patterns of the supraspinatus, infraspinatus, and subscapularis appeared similar in both groups. Dual fine-wire electromyography offers insight into the complex role of shoulder girdle muscle function in normal movement and in instability. Altered patterns of shoulder girdle muscle activity and imbalances in muscle forces support the theory that impaired coordination of shoulder girdle muscle activity and inefficiency of the dynamic stabilizers of the glenohumeral joint are involved in the etiology of MDI. Interestingly, the abnormalities are in the deltoid rather than the muscles of the rotator cuff.

The Effects of Thermal Capsulorrhaphy and Rotator Interval Closure on Multidirectional Laxity in the Glenohumeral Joint (SS-47)

The Effects of Thermal Capsulorrhaphy and Rotator Interval Closure on Multidirectional Laxity in the Glenohumeral Joint (SS-47)

Inferior capsular shift for multidirectional instability following failed laser-assisted capsular shrinkage

This report is a prospective study of 10 consecutive patients treated by open inferior capsular shift following failed laser-assisted capsular shrinkage. Six patients had true multidirectional instability, 2 had anteroinferior instability with multidirectional laxity, and 2 had posteroinferior instability with multidirectional laxity. An anterior approach was used and a humeral-side capsular shift performed. The mean period of follow-up was 33 months (range, 18-47 months). On the basis of the Rowe system,9 patients had excellent results and 1 had a poor result at final follow-up. The mean score improved from 37.5 to 94 points on the Rowe scale, from 73 to 90.4 points on the Constant scale, and from 1.6 to 7.7 points on a numeric satisfaction scale (P <.001 for all). The one poor result was in the only patient who underwent multiple attempts at open stabilization prior to laser-assisted capsular shrinkage. There were no complications. We conclude that the results of an inferior capsular shift for multidirectional instability are not necessarily adversely affected by a previous failed laser-assisted capsular shrinkage procedure. (J Shoulder Elbow Surg 2002;11:305-8)

Anterior instability of the glenohumeral joint with humeral avulsion of the glenohumeral ligament. A review of 41 cases.

We studied retrospectively a consecutive series of 547 shoulders in 529 patients undergoing operation for instability. In 41, the cause of instability was considered to be lateral avulsion of the capsule, including the inferior glenohumeral ligament, from the neck of the humerus, the HAGL lesion. In 35, the lesion was found at first exploration, whereas in six it was noted at revision of a previous failed procedure. In both groups, the patients were older on average than those with instability from other causes. Of the primary cases, in 33 (94.3%) the cause of the first dislocation was a violent injury; six (17.4%) had evidence of damage to the rotator cuff and/or the subscapularis. Only four (11.4%) had a Bankart lesion. In patients undergoing a primary operation in whom the cause of the first dislocation was a violent injury, who did not have a Bankart lesion and had no suggestion of multidirectional laxity, the incidence of HAGL was 39%.

Anterior instability of the glenohumeral joint with humeral avulsion of the glenohumeral ligament

We studied retrospectively a consecutive series of 547 shoulders in 529 patients undergoing operation for instability. In 41, the cause of instability was considered to be lateral avulsion of the capsule, including the inferior glenohumeral ligament, from the neck of the humerus, the HAGL lesion. In 35, the lesion was found at first exploration, whereas in six it was noted at revision of a previous failed procedure. In both groups, the patients were older on average than those with instability from other causes. Of the primary cases, in 33 (94.3%) the cause of the first dislocation was a violent injury; six (17.4%) had evidence of damage to the rotator cuff and/or the subscapularis. Only four (11.4%) had a Bankart lesion. In patients undergoing a primary operation in whom the cause of the first dislocation was a violent injury, who did not have a Bankart lesion and had no suggestion of multidirectional laxity, the incidence of HAGL was 39%.