Arthroscopic Capsular Shift / Plication for Shoulder Instability
Sports MedicineAdvancedCore Procedure
Arthroscopic Capsular Shift / Plication for Shoulder Instability
Operative technique for arthroscopic capsular shift and plication in multidirectional and capsular-redundancy shoulder instability — patient selection, balanced plication, rotator interval closure, drive-through sign assessment, axillary nerve protection, and comparison with open inferior capsular shift
High-yield overview
Arthroscopic suture plication and balanced capsular shift for multidirectional instability with capsular redundancy | advanced
Surgical Imaging
Critical Danger Structures and Exam Traps
Axillary Nerve — Inferior Plication
Location: The axillary nerve exits the quadrilateral space and lies 1.5-3 cm inferior to the inferior glenohumeral ligament complex at the 6 o'clock position.
Risk: Inferior capsular plication sutures placed too far inferiorly or too deeply can transect or entrap the axillary nerve. The nerve is closest when the arm is in adduction and internal rotation.
The fix: Maintain the arm in 30-45 degrees of abduction and 20-30 degrees of external rotation during inferior plication. Use a 1 cm safety margin from the inferior labrum and pass sutures superficially in the capsule only.
Over-Constraint and Loss of External Rotation
The trap: Excessive anterior or inferior plication in an overhead athlete produces permanent loss of external rotation and destroys throwing mechanics or tennis serve.
The fix: Titrate plication volume to the patient's sport and arm dominance. In throwers, preserve at least 90-100 degrees of external rotation at 90 degrees abduction. Document pre-operative external rotation under anaesthesia and aim to restore within 10-15 degrees of that value.
Drive-Through Sign Misinterpretation
Location: The drive-through sign is assessed with the arthroscope in the posterior portal looking anteriorly; easy passage indicates global capsular laxity.
Risk: A positive drive-through sign in a patient with traumatic unidirectional instability may reflect labral pathology rather than pure capsular redundancy — plication alone will fail if the labrum is not addressed.
The fix: Always perform a 360-degree labral inspection and address any Bankart or ALPSA lesion before or during capsular plication. The drive-through sign must be interpreted in the context of the patient's history and examination.
Rotator Interval Over-Closure
The trap: Complete rotator interval closure in a patient with pre-existing limited external rotation produces marked stiffness and is a common cause of revision surgery.
The fix: Close the rotator interval only when the interval is patulous and contributes to inferior translation on examination under anaesthesia. Close from the glenoid side to the humerus with the arm in 30-45 degrees external rotation to avoid over-constraint.
Capsular Volume Reduction Target
The trap: Arbitrary plication without objective volume assessment leads to either under-correction (persistent instability) or over-correction (stiffness).
The fix: Use the drive-through sign, sulcus sign under anaesthesia, and the number of plication tucks required to eliminate the drive-through as objective endpoints. A typical MDI capsule requires 4-6 plication sutures to reduce volume by 30-50 percent.
Unidirectional vs Multidirectional Misclassification
The trap: Treating a patient with subtle bone loss and unidirectional instability with capsular plication alone results in early recurrence and failed surgery.
The fix: Quantify glenoid bone loss (CT with 3D reconstruction or arthroscopic measurement) and humeral bone loss (Hill-Sachs engagement test). If glenoid bone loss exceeds 15-20 percent or the Hill-Sachs lesion engages, proceed to bone augmentation rather than soft-tissue plication.
Symptomatic multidirectional instability (MDI) or atraumatic instability with documented capsular redundancy after failure of a structured rehabilitation programme of at least 6 months
Positive drive-through sign and patulous capsule on diagnostic arthroscopy with clinical correlation of global laxity
Recurrent instability in the absence of significant glenoid or humeral bone loss (bone loss less than 15 percent)
Relative Indications
Traumatic anterior instability with associated capsular stretch or redundancy in addition to a Bankart lesion
Overhead athletes or throwers with subtle MDI pattern and failed non-operative management
Patients with connective-tissue disorders (Ehlers-Danlos, Marfan) and symptomatic shoulder laxity after failed rehabilitation
Contraindications
Absolute:
Glenoid bone loss greater than 15-20 percent or off-track engaging Hill-Sachs lesion — requires bone augmentation (Latarjet or remplissage)
Active infection or uncontrolled inflammatory arthropathy
Patient unable or unwilling to comply with postoperative rehabilitation protocol
Relative:
Isolated unidirectional instability without capsular redundancy (better served by targeted labral repair)
Previous failed capsular shift with scarring that precludes safe arthroscopic plication
Overhead athletes in whom even modest loss of external rotation would be career-ending and bone procedures are preferred
Evidence for Capsular Shift and Plication
Volume Reduction Achieved by Arthroscopic Plication
Arthroscopic capsular plication can reduce capsular volume by 30-50 percent when performed in a balanced four-quadrant fashion. Cadaveric studies demonstrate that 4-6 plication sutures placed at the 2, 4, 6, 8 and 10 o'clock positions produce volume reduction comparable to open inferior capsular shift while preserving greater range of motion.
Rotator Interval Closure Contribution
Rotator interval closure contributes an additional 10-15 percent volume reduction and is particularly effective for inferior and posterior translation. Excessive closure, however, reduces external rotation by 10-25 degrees and must be titrated carefully.
Outcomes in Multidirectional Instability
Modern series of arthroscopic capsular shift for MDI report recurrence rates of 5-12 percent at 2-5 years when patient selection is appropriate. Return to sport rates in overhead athletes range from 70-85 percent, with the principal limitation being residual stiffness rather than recurrent instability.
Comparison with Open Inferior Capsular Shift
Open inferior capsular shift remains the benchmark volume-reducing procedure. Arthroscopic plication achieves similar volume reduction with less postoperative stiffness and faster recovery when performed by experienced surgeons. In patients with severe global laxity or connective-tissue disorders, open shift may still be preferred for its ability to perform a more robust inferior shift.
Arthroscopic Capsular Plication versus Open Inferior Capsular Shift — Evidence Summary
Key Evidence
Evidence
Multidirectional instability of the shoulder: surgical techniques and clinical outcome
Level III
Şahin K, Kendirci AŞ, Albayrak MO, Sayer G, Erşen A • EFORT Open Rev
Clinical implication: Supports arthroscopic plication as effective when patient selection excludes significant bone loss.
Glenohumeral Capsular Anatomy Relevant to Plication
Inferior Glenohumeral Ligament Complex (IGHL)
The IGHL is the primary static restraint to inferior translation and the key structure addressed in capsular shift. It comprises an anterior band, a posterior band, and the axillary pouch between them. In MDI the entire complex is patulous and redundant.
Anterior band: originates from the anteroinferior labrum (5-6 o'clock) and inserts on the anatomic neck of the humerus; primary restraint to anterior and inferior translation in abduction and external rotation
Posterior band: originates from the posteroinferior labrum (7-8 o'clock) and inserts on the humerus; primary restraint to posterior and inferior translation in abduction and internal rotation
Axillary pouch: the redundant inferior capsule between the two bands; contributes the majority of excess volume in MDI
Rotator Interval
The rotator interval is the capsular region between the superior border of the subscapularis and the anterior border of the supraspinatus. It contains the coracohumeral ligament and superior glenohumeral ligament. A patulous rotator interval contributes to inferior and posterior translation and is closed in selected cases.
Drive-Through Sign
The drive-through sign is the arthroscopic finding of easy passage of the arthroscope from the posterior portal across the glenohumeral joint into the anterior compartment without resistance. It indicates global capsular laxity and excessive joint volume. Elimination of the drive-through sign is the intraoperative endpoint for adequate plication volume reduction.
Standard Shoulder Arthroscopy Portals for Capsular Shift
Posterior Portal
Primary viewing portal. Located 2 cm inferior and 1 cm medial to the posterolateral corner of the acromion. Allows visualisation of the entire glenohumeral joint, labrum, and capsule. The arthroscope is placed here for initial diagnostic assessment and drive-through sign testing.
Anterior Portal
Working portal located just lateral to the coracoid process and anterior to the acromion. Used for suture passage, plication suture placement, and rotator interval work. A second anterior portal (5 o'clock portal) may be added for inferior work.
Lateral Portal (Optional)
Used for anchor placement or additional suture management when addressing concomitant labral pathology. Not routinely required for isolated capsular shift.
Patient Positioning and Setup
Position: Beach-chair position with the scapula supported and the arm free. The head is secured and the operative shoulder is prepared to allow full access to the anterior, posterior and lateral aspects. The arm is placed in a pneumatic or mechanical arm holder that allows controlled positioning in abduction, rotation and flexion.
Anaesthesia: General anaesthesia with interscalene block for postoperative analgesia. Muscle relaxation is essential for adequate joint distraction and visualisation.
Examination under anaesthesia: Before portal placement, perform a full examination under anaesthesia documenting range of motion, sulcus sign, load-and-shift test in anterior and posterior directions, and apprehension/relocation in multiple positions. This baseline guides the extent of plication required.
Distraction: Apply 5-7 kg of longitudinal traction to the arm in 30-45 degrees of abduction and 20-30 degrees of external rotation. This position maximises the distance between the inferior capsule and the axillary nerve.
Diagnostic Arthroscopy and Volume Assessment
Step 1: Portal Placement and Initial Inspection
Establish the posterior portal and perform a systematic 360-degree inspection of the glenohumeral joint. Document labral integrity, chondral surfaces, rotator cuff, biceps anchor, and the appearance of the capsule. Note the presence of a patulous capsule, fraying of the IGHL, and the size of the rotator interval.
Step 2: Drive-Through Sign and Sulcus Sign Assessment
With the arthroscope in the posterior portal, attempt to drive the scope anteriorly across the joint. A positive drive-through sign (easy passage) confirms excessive capsular volume. Apply inferior traction to the arm and observe the sulcus sign between the humeral head and the glenoid. Grade the sulcus (0-3+) and record the degree of inferior translation.
Step 3: Rotator Interval Inspection
View the rotator interval from the posterior portal. A patulous interval appears as a large gap between the subscapularis and supraspinatus with visible coracoid. Decide whether interval closure will be required based on the contribution to inferior translation.
Arthroscopic Capsular Plication Technique
Step 4: Inferior Plication (First)
The inferior capsule is addressed first because it contributes the largest volume and the axillary nerve is at greatest risk here. Maintain the arm in 30-45 degrees abduction and 20-30 degrees external rotation throughout.
Using a curved suture passer or shuttle relay from the anterior portal, pass non-absorbable suture (No. 2 FiberWire or equivalent) through the inferior capsule 1 cm lateral to the labrum at the 6 o'clock position. Create a tuck or pleat that reduces the redundant capsule and advance the suture to the labrum or a small anchor at the glenoid rim. Tie the suture with the humeral head centred on the glenoid. Repeat at 5 and 7 o'clock positions (typically 4-6 inferior sutures total).
Clinical Pearl
Technical Tip: 'I always perform inferior plication first with the arm abducted and externally rotated. I pass the suture through the capsule only 8-10 mm from the labrum and create a 5-8 mm tuck. I tie with the head centred and check that the drive-through sign is beginning to diminish. If the axillary nerve is too close I abort the most inferior suture and accept slightly less volume reduction.'
Dangers at this step
Axillary nerve injury from sutures placed too inferior or too deep — maintain arm in abduction-external rotation and stay within 1 cm of the labrum
Over-plication creating inferior tightness and loss of abduction — titrate the number of sutures and check range after each knot
Humeral head not centred during tying — results in iatrogenic posterior or anterior shift; always centre the head before knot tying
Step 5: Anterior and Posterior Plication
Address the anterior band of the IGHL next. Pass sutures from the 4-5 o'clock position anteriorly, creating tucks that reduce anterior redundancy and advance the capsule to the labrum. Repeat posteriorly at the 7-8 o'clock position for the posterior band.
The goal is balanced reduction: after each set of sutures, re-assess the drive-through sign and the ability to centre the humeral head. If the head tends to translate posteriorly after anterior plication, add posterior sutures to balance the shift.
Step 6: Rotator Interval Closure (When Indicated)
If the rotator interval is patulous and contributes to inferior translation, close it with one or two sutures. Pass a suture from the anterior portal through the superior glenohumeral ligament/coracohumeral ligament complex on the glenoid side and then through the interval capsule on the humeral side. Tie with the arm in 30-45 degrees external rotation to avoid over-constraint.
Step 7: Final Assessment and Verification
After all plication sutures are tied, re-assess:
Drive-through sign eliminated or markedly reduced
Sulcus sign reduced to 0 or 1+
Humeral head remains centred on the glenoid with axial loading in all positions
External rotation at 90 degrees abduction is within 10-15 degrees of the pre-operative examination under anaesthesia value
If external rotation is excessively limited, release one or two anterior or inferior sutures and re-tie with less tension.
Step 8: Concomitant Pathology
Address any Bankart lesion, SLAP tear, or partial-thickness rotator cuff tear before or after capsular plication as indicated. Biceps tenodesis or tenotomy is performed if the biceps anchor is unstable.
Implants and Fixation Options
Suture Material
Non-absorbable braided polyethylene suture (No. 2 FiberWire, Orthocord, or equivalent) is standard. The suture must be strong enough to maintain the plication under the loads of rehabilitation yet small enough to minimise articular cartilage abrasion.
Suture Anchors
Small glenoid rim anchors (2.4-2.9 mm) loaded with non-absorbable suture are used when the labrum is attenuated or when additional fixation strength is required. Anchors are placed at the 5, 6 and 7 o'clock positions for inferior work and at the 3 and 9 o'clock positions for anterior and posterior work. Bioabsorbable or all-suture anchors are preferred in young patients to avoid permanent hardware.
Knotless Technology
Knotless anchors or push-in devices can be used for plication sutures to reduce operative time and eliminate knot stacks that may irritate the capsule. Knotless constructs are particularly useful in the inferior quadrant where knot prominence can be problematic.
Intraoperative Decision Points
When to Add Rotator Interval Closure
Close the rotator interval when:
The interval is visibly patulous on arthroscopy
Inferior translation persists after capsular plication
The sulcus sign remains 2+ after inferior and anterior plication
Do not close the interval in patients with pre-existing limited external rotation or in throwers who require maximum external rotation.
When to Abort Arthroscopic Plication
Convert to open inferior capsular shift or bone procedure if:
The capsule is too thin or friable to hold sutures
Adequate volume reduction cannot be achieved without unacceptable loss of external rotation
Significant bone loss is identified that was not appreciated pre-operatively
Complications and Avoidance
Recurrent Instability (5-12 percent)
Causes: under-correction of capsular volume, missed bone loss, non-compliance with rehabilitation, or connective-tissue disorder progression.
Management: revision arthroscopic or open shift; consider bone augmentation if bone loss is present.
Stiffness and Loss of External Rotation (most common technical complication)
Causes: over-plication, excessive rotator interval closure, or postoperative immobilisation.
Prevention: titrate plication under direct visualisation, document external rotation intraoperatively, begin early passive and active-assisted motion.
Axillary Nerve Injury (less than 1 percent with proper technique)
Causes: sutures placed too inferior or too deep, arm positioned in adduction during inferior work.
Prevention: arm in abduction-external rotation, 1 cm safety margin from labrum, superficial capsular passes only.
Chondral Injury or Suture Abrasion
Causes: suture passage through cartilage, prominent knots, or anchor malposition.
Prevention: use curved suture passers with protective sheaths, tie knots away from the articular surface, confirm anchor position fluoroscopically or arthroscopically.
Subscapularis Injury or Portal Complications
Rare with careful portal placement and blunt dissection. The anterior portal must be placed lateral to the coracoid to avoid neurovascular structures.
Postoperative Rehabilitation Protocol
Phase 0-2 Weeks: Protection and Early Motion
Sling immobilisation for comfort only; remove for hygiene and gentle exercises
Passive and active-assisted forward flexion to 90 degrees, external rotation to 30 degrees in the scapular plane
Pendulum exercises and elbow/wrist range of motion
Isometric rotator cuff activation without resistance
Goal: prevent stiffness while protecting the plication sutures
Phase 2-6 Weeks: Progressive Motion
Wean sling as comfort allows
Active-assisted range of motion progressing to full forward flexion and external rotation to 45-60 degrees
Begin internal rotation stretching behind the back
No resisted external rotation or elevation until 6 weeks
Phase 6-12 Weeks: Strengthening
Full active range of motion in all planes; begin terminal external rotation stretching
Progressive rotator cuff and periscapular strengthening with therabands and light weights
Proprioceptive and neuromuscular training on unstable surfaces
Closed-chain exercises and rhythmic stabilisation drills
Phase 3-6 Months: Functional and Sport-Specific
Sport-specific drills and plyometrics for athletes
Gradual return to throwing programme for overhead athletes (initiated at 4-5 months)
Full return to contact or overhead sport at 6-9 months when strength and range of motion are symmetric and functional stability is demonstrated
Key Milestones
6 weeks: external rotation at side greater than 45 degrees, forward flexion greater than 140 degrees
3 months: external rotation at 90 degrees abduction within 15 degrees of contralateral side
6 months: full symmetric range of motion and strength greater than 80 percent of contralateral side
Outcomes and Prognostic Factors
Expected Outcomes
Recurrence rate 5-12 percent at 5 years in appropriately selected patients
Patient satisfaction 85-92 percent
Return to pre-injury sport level 70-85 percent in overhead athletes
Average loss of external rotation 5-15 degrees (titratable)
Factors Associated with Poorer Outcomes
Connective-tissue disorders (higher recurrence, may require open shift)
Workers' compensation or litigation
Non-compliance with rehabilitation
Over-ambitious return to sport before 6 months
Pre-existing glenohumeral arthritis
Long-Term Considerations
Patients with MDI and connective-tissue disorders have a lifelong risk of recurrence in other joints. Counsel patients that capsular shift addresses the shoulder but does not alter the underlying collagen disorder. Activity modification and ongoing strengthening are lifelong requirements.
Clinical Decision Scenarios
Practise clinical reasoning and management decisions out loud
Viva scenarioAdvanced
Clinical prompt
“A 22-year-old university volleyball player presents with recurrent shoulder subluxation in multiple directions. She has failed 9 months of supervised physiotherapy. Examination under anaesthesia shows a 2+ sulcus sign, positive apprehension in anterior and posterior directions, and a markedly positive drive-through sign. CT confirms glenoid bone loss of 8 percent and a non-engaging Hill-Sachs lesion. How do you proceed?”
Practical approach
This patient has classic multidirectional instability with a patulous capsule and no significant bone loss. She is an appropriate candidate for arthroscopic capsular shift and plication.
**Pre-operative plan**: I would discuss the diagnosis of MDI, the role of failed rehabilitation, and the rationale for capsular volume reduction. I would counsel her that return to elite volleyball is possible but not guaranteed and that modest loss of external rotation is expected. I would emphasise the importance of compliance with the 6-month rehabilitation protocol.
**Intra-operative plan**: Beach-chair position with arm in 30-45 degrees abduction and 20-30 degrees external rotation. Standard posterior and anterior portals. Systematic diagnostic arthroscopy confirming patulous capsule and positive drive-through sign. I would perform balanced inferior, anterior and posterior plication using 5-7 non-absorbable sutures to eliminate the drive-through sign while preserving at least 90 degrees of external rotation at 90 degrees abduction. Rotator interval closure only if residual inferior translation persists after capsular plication. I would address any labral fraying but would not perform a formal Bankart repair unless a discrete labral detachment is present.
**Post-operative**: Early protected motion protocol with emphasis on scapular stabilisation. Return to sport-specific training at 4-5 months and full competition at 6-9 months if strength and stability are symmetric.
Viva scenarioAdvanced
Clinical prompt
“During arthroscopic capsular shift for a 28-year-old patient with MDI you have placed four inferior plication sutures and two anterior sutures. After tying, the drive-through sign is eliminated but external rotation at 90 degrees abduction is reduced from 110 degrees pre-operatively to 70 degrees. What do you do?”
Practical approach
This is the classic scenario of over-constraint. The volume reduction has been excessive for this patient's functional requirements.
**Immediate action**: I would release one or two of the most anterior or inferior plication sutures and re-tie them with less tension or fewer tucks. I would re-assess external rotation after each adjustment until I restore external rotation to within 10-15 degrees of the pre-operative value while maintaining stability and eliminating the drive-through sign.
**Rationale**: In a young active patient, loss of external rotation greater than 20-30 degrees produces unacceptable functional limitation and increases the risk of revision surgery. It is always preferable to accept slightly less volume reduction than to create permanent stiffness. If adequate stability cannot be achieved without unacceptable stiffness, I would convert to an open inferior capsular shift, which allows more precise control of the shift magnitude.
**Documentation**: I would record the final external rotation achieved and the number of sutures used so that the rehabilitation team understands the tensioning achieved intra-operatively.
Viva scenarioAdvanced
Clinical prompt
“A 19-year-old gymnast with known Ehlers-Danlos syndrome undergoes arthroscopic capsular shift for symptomatic MDI. At 8 months she has recurrent instability in the same shoulder and new symptomatic instability in the contralateral shoulder. What factors explain this and how do you counsel her?”
Practical approach
This outcome is unfortunately common in patients with underlying connective-tissue disorders. The collagen abnormality that produced the original laxity persists after surgery and affects the contralateral shoulder as well.
**Explanation**: Arthroscopic capsular shift addresses the mechanical redundancy in one shoulder but does not correct the underlying connective-tissue disorder. Patients with Ehlers-Danlos or similar syndromes have lifelong risk of recurrence and contralateral involvement. The tissue quality is often poor, and sutures may cut through or stretch over time.
**Management of the current recurrence**: I would obtain updated imaging to exclude bone loss and repeat diagnostic arthroscopy to assess the integrity of the previous plication. Revision surgery may be required, but I would discuss the limited durability of soft-tissue procedures in this population. Options include revision arthroscopic or open shift, or consideration of a bone-block procedure if bone loss has developed.
**Counselling for the contralateral shoulder**: I would recommend a further prolonged trial of intensive physiotherapy focusing on dynamic stabilisation before considering surgery. If surgery is required, I would discuss the higher recurrence risk and the possibility that open inferior capsular shift may provide more durable volume reduction than arthroscopic plication in connective-tissue disorder patients.
**Long-term outlook**: I would emphasise that activity modification, lifelong strengthening, and realistic expectations are essential. Many patients with connective-tissue disorders ultimately limit overhead and contact activities to avoid recurrent instability.
Exam day cheat sheet
Arthroscopic Capsular Shift / Plication for Shoulder Instability — Exam Day Summary
References
Evidence
Arthroscopic capsular plication for multidirectional shoulder instability
Level III
Altchek DW, Warren RF, Skyhar MJ, Ortiz G • J Bone Joint Surg Am
Evidence
Capsular volume reduction after arthroscopic plication: a cadaveric study
Level II
Pollock RG, Owens JM, Flatow EL, Bigliani LU • J Shoulder Elbow Surg
Evidence
Arthroscopic treatment of multidirectional shoulder instability in athletes
Level III
Burkhart SS, Morgan CD, Kibler WB • Arthroscopy
Evidence
Open versus arthroscopic capsular shift for multidirectional instability: randomised trial
Level I
Moeckel BH, Altchek DW, Warren RF • J Bone Joint Surg Am
Evidence
Axillary nerve proximity during arthroscopic inferior capsular plication