SICK Scapula Syndrome
- Scapular dyskinesis is usually a SIGN of underlying pathology, not a primary diagnosis
- SICK Scapula: Scapular malposition, Inferior medial border prominence, Coracoid pain, dysKinesis
- Legs and trunk generate 50% of the force in throwing (Kinetic Chain)
- Pectoralis minor tightness is a key driver of anterior tilt
- Serratus anterior weakness causes medial winging
- “Assess for 'Winging' during wall push-up (Serratus)
- “Scapular Assistance Test (SAT): Does manual stabilization relieve pain?
- “Scapular Retraction Test (SRT): Does retraction increase power?
- “Look for 'Pseudowinging' (Long thoracic nerve palsy vs Dyskinesis)
Contraindication. Scapular dyskinesis is a functional problem managed with REHAB. Do not operate on the scapula unless there is a structural cause (e.g., osteochondroma, nerve palsy).
Scapular malposition, Inferior border prominence, Coracoid pain, dysKinesis of movement. Learn this definition.
Proximal Stability for Distal Mobility. Weak core/hips transfer increased load to the shoulder. Rehab starts at the legs/trunk.
Always rule out Long Thoracic Nerve (Serratus) and Spinal Accessory Nerve (Trapezius) palsy. Dyskinesis is usually bilateral/functional; Palsy is unilateral/structural.
- Pathology
- Functional Imbalance
- Management
- Physiotherapy (Kinetic Chain)
- Key Feature
- SICK Syndrome
- Pathology
- Nerve Injury (Structural)
- Management
- Observe to Transfer
- Key Feature
- Medial Winging
- Pathology
- Bursitis / Osteochondroma
- Management
- Injection to Bursectomy
- Key Feature
- Crepitus
- Scapular Dyskinesis
- Muscle Imbalance / Inhibition
- True Winging (Nerve Palsy)
- Neurological Injury
- Scapular Dyskinesis
- Subtle, often Type 1-3 pattern
- True Winging (Nerve Palsy)
- Gross deformity
- Scapular Dyskinesis
- Pain / Impingement
- True Winging (Nerve Palsy)
- Weakness / Deformity
- Scapular Dyskinesis
- Physiotherapy (Scapula Setting)
- True Winging (Nerve Palsy)
- Observation / Nerve Transfer / Fusion
SICKSICK Scapula
Hook:A SICK scapula needs rehab, not surgery
CORERehab Principles
Hook:Restore the CORE stability
Overview and Epidemiology
Scapular dyskinesis is often a secondary phenomenon reacting to glenohumeral pathology (e.g., instability, cuff tear, SLAP). It serves as a compensatory mechanism (like a limp). Treating the dyskinesis is essential, but you must also address the primary pathology.
Alteration of the normal position and motion of the scapula during scapulohumeral movements.
- Stable Base: For rotator cuff origin.
- Gleneohumeral Alignment: Maintains ball-socket congruency (glenoid tracks the head).
- Force Transfer: Integral link in the kinetic chain transferring energy from trunk to arm.
Normal Scapulohumeral Rhythm
Dyskinesis is defined as a loss of the normal rhythm of scapular motion ("dysrhythmia" / shuddering), and the whole topic turns on abnormal scapular movement during elevation — so the normal rhythm it deviates from is worth stating explicitly.
The 2:1 rhythm
- Full arm elevation to about 180 degrees is produced by combined glenohumeral and scapulothoracic motion in an overall ratio of roughly 2:1 (the classic Inman scapulohumeral rhythm) — approximately 120 degrees of glenohumeral elevation to 60 degrees of scapulothoracic upward rotation across the whole arc.
- The ratio is not constant: in the first roughly 30 degrees there is a "setting" phase where motion is predominantly glenohumeral and the scapula is comparatively stable; the scapula then contributes progressively more through mid- and late-range.
The three coupled scapular motions
- As the arm elevates the scapula must simultaneously upwardly rotate, posteriorly tilt, and externally rotate. Together these keep the acromion clear of the rotator cuff (preserving the subacromial space) and keep the glenoid tracking under the humeral head.
- The upward-rotation force couple is the upper trapezius, lower trapezius and serratus anterior; the serratus anterior is the prime upward rotator and also drives posterior tilt and external rotation. Inhibition or weakness of serratus or lower trapezius (with relative upper-trapezius dominance) unbalances the couple and produces the Kibler patterns and secondary impingement.
Normal elevation is about 120 degrees glenohumeral to 60 degrees scapulothoracic (a 2:1 rhythm), after an early setting phase, with the scapula upwardly rotating, posteriorly tilting and externally rotating. Scapular dyskinesis is the visible loss of this smooth rhythm — premature elevation (shrug), early/excessive winging, or dysrhythmic "shuddering" on lowering.
Pathophysiology and Mechanisms
Key Force Couples
Stability relies on balanced force couples. In dyskinesis, these are disrupted.
- Trapezius Force Couple:
- Upper Trap: Elevates.
- Lower Trap: Depresses/Retracts.
- Imbalance: Overactive Upper + Weak Lower = Scapular Shrug (Type III).
- Serratus Anterior:
- Protracts and stabilizes medial border.
- Weakness = Medial Winging (Type II).
- Pectoralis Minor:
- Depresses and Anteriorly Tilts.
- Tightness = Anterior Tilt (Type I).
Classification Systems
Kibler Classification
Qualitative visual assessment during elevation.
- Prominence
- Inferior Medial Angle
- Mechanism
- Anterior Tiliting
- Associated Muscle
- Tight Pect Minor / Weak Lower Trap
- Prominence
- Entire Medial Border
- Mechanism
- Internal Rotation
- Associated Muscle
- Weak Serratus Anterior
- Prominence
- Superior Medial Border
- Mechanism
- Early Elevation (Shrug)
- Associated Muscle
- Overactive Upper Trap
- Prominence
- Symmetric
- Mechanism
- Normal Motion
- Associated Muscle
- Normal
IMSKibler Classification
Hook:Inferior, Medial, Superior (1, 2, 3)
Clinical Assessment
- Inspect from back. Look for asymmetry in resting height and distance from spine.
- Check for Pect Minor Tightness (Forward shoulder posture).
- Palpate Coracoid (Tenderness).
- Scapular Dyskinesis Test: Patient performs weighted flexion/abduction (3-5 lbs).
- Observe for medial border prominence or dysrhythmia (shuddering).
- Wall Push-Up: Accentuates winging (Serratus weakness).
Corrective Maneuvers
- Examiner actively assists upward rotation and posterior tilt during elevation.
- Positive Test: Reduction in impingement pain.
- Significance: Confirms that scapular dysfunction is contributing to symptoms.
- Examiner manually stabilizes medial border in retraction.
- Patient performs isometric elevation.
- Positive Test: Increase in strength (or reduction in pain).
- Significance: Indicates weak retractors (Rhomboids/Traps).
The Scapular Dyskinesis Test: The Reliable Yes/No Method
The topic and the 2013 Summit repeatedly say the reliable bedside method is a yes/no (present vs absent) judgement rather than the I/II/III subtype — but how that test is actually performed and scored is worth spelling out, because the subtype reliability is only moderate (kappa around 0.4) while the binary method is the one to use.
How to perform the Scapular Dyskinesis Test (McClure/Kibler)
- Observe the patient from behind, both shoulders exposed.
- The patient performs about five repetitions of bilateral weighted shoulder flexion and about five of abduction, holding light hand weights (for example around 3 to 5 lb / 1 to 2 kg, scaled to body weight), at a controlled tempo and through full range.
- Watch the ascending and the descending (eccentric) phases — dysrhythmia is often most obvious on lowering.
How to score it
- Classify each side as showing obvious dyskinesis (clear medial-border or inferior-angle winging, or a premature/excessive scapular elevation or "shuddering" dysrhythmia), subtle, or normal.
- For reliability, collapse this to a binary present (yes) versus absent (no) judgement — this dichotomy is reproducible, whereas assigning a Kibler subtype is not.
Then establish relevance
- A "yes" only matters if it is contributing to symptoms, so pair it with the corrective tests above: a positive Scapular Assistance Test (assist upward rotation/posterior tilt → impingement pain falls) or Scapular Retraction Test (stabilise the retracted scapula → strength rises or pain falls) links the dyskinesis to the patient's complaint and predicts a good response to scapular rehabilitation.
Use the binary present/absent Scapular Dyskinesis Test (about five reps of weighted flexion and abduction, observed from behind, eccentric phase included) — do not try to assign a reliable Kibler subtype (kappa around 0.4). Confirm the finding is symptomatic with a positive SAT or SRT before building rehab around it.
Investigations
Scapular Dyskinesis is a Clinical Diagnosis. Imaging is used to rule out other causes, not to verify dyskinesis.
Electromyography is the gold standard if nerve palsy is suspected (Long Thoracic / Spinal Accessory). It differentiates neuropathic weakness from functional inhibition.
Imaging Protocol
- AP / Axillary / Outlet.
- Check for structural causes: Osteochondroma (Snapping Scapula), fracture malunion, AC joint pathology.
- Assess for the "Primary" cause: Rotator Cuff Tear, Labral Tear (SLAP).
- Assess periscapular muscles for denervation atrophy (edema/fatty infiltration).
- Indicated for "Snapping Scapula" to visualize rib cage incongruity or Luschka's tubercle.
Management Algorithm
The Mainstay of Treatment
Protocol phases (Kibler):
- Acute Phase:
- Address primary pathology (e.g., pain control, cuff inflammation).
- Soft tissue work: Release tight Pectoralis Minor and Posterior Capsule.
- Core stability.
- Recovery Phase (Static):
- Isometrics ("Scapular Setting").
- "Low Row", "Inferior Glide".
- Closed chain exercises (Wall slides).
- Maintenance Phase (Dynamic):
- Open chain strengthening.
- Plyometrics.
- Sport-specific mechanics.
- 1Diagnosis
Identify Dyskinesis + Primary Pathology
Refer Physio
- 2Phase 1: Flexibility
Stretch Pect Minor + Post Cap
Improved Posture
- 3Phase 2: Control
Closed Chain + Isometric Setting
Stable Base
- 4Phase 3: Strength
Open Chain + Sport Specific
Return to Play
Surgical Technique
Arthroscopic Release
- Indication: Persistent anterior tilt + coracoid pain refractory to stretching.
- Position: Beach chair or Lateral Decubitus.
- Visualisation: Scope in standard posterior portal.
- Technique: Locate Pect Minor insertion at coracoid. Release using radiofrequency probe.
- Outcome: Improves scapular tipping and reduces impingement.
Complications
- Consequence
- Failed Cuff Rehab
- Solution
- Include Kinetic Chain
- Consequence
- Upper Trap Dominance
- Solution
- Focus on Lower Trap
- Consequence
- Bursal Inflammation
- Solution
- Bursectomy (Rare)
- Consequence
- Restricted Chest Expansion
- Solution
- Pre-op Warning
Rehabilitation Protocols
Start Here. Hand fixed (e.g., Wall push-up, Quadruped). Promotes joint stability via compression and co-contraction. Safer for rotator cuff.
Progress To This. Hand free (e.g., Dumbbell press, Throwing). Requires greater dynamic control. Higher shear forces.
- Target Muscle
- Posterior Capsule
- Phase
- Phase 1
- Target Muscle
- Pectoralis Minor
- Phase
- Phase 1
- Target Muscle
- Serratus / Traps
- Phase
- Phase 2
- Target Muscle
- Serratus Anterior
- Phase
- Phase 2
- Target Muscle
- Serratus Anterior
- Phase
- Phase 3
- Target Muscle
- Lower Trap / Rhomboids
- Phase
- Phase 3
Postoperative Care
There is rarely 'Postoperative' care as surgery is rare. For Pect Minor release:
Pect Minor Release Rehab
- Sling for comfort only.
- Immediate active assist ROM.
- Focus on posterior tilt and retraction.
- Lower trapezius activation.
- Unrestricted strengthening.
Outcomes and Prognosis
Highly Successful. 80-90% of patients improve with a dedicated, scapula-focused rehabilitation program (usually 3-6 months).
Common if patients revert to poor mechanics or stop maintenance exercises.
Outcomes for nerve transfers (Pect Major) are variable. Fusion provides stability but eliminates scapulothoracic motion (loss of 30% elevation).
Guidelines, Registries & Global Practice
- Position on Scapular Dyskinesis
- Impairment, not a diagnosis; reliable yes/no assessment; scapular rehab within a comprehensive programme
- Position on Scapular Dyskinesis
- Address scapular control as part of rotator cuff and impingement rehabilitation; surgery reserved for structural causes
- Position on Scapular Dyskinesis
- Physiotherapy-led, kinetic-chain rehabilitation first-line; refer for nerve studies if true winging suspected
- Position on Scapular Dyskinesis
- Screen overhead athletes; combine GIRD, cuff strength and scapular control in injury-prevention programmes
Dyskinesis is found in 60-100% of shoulders with injury (rotator cuff disease, instability, SLAP) and in a high proportion of asymptomatic overhead athletes. There is no implant registry — this is a functional, non-operative condition.
Access to specialist sports physiotherapy, video and 3D motion analysis, and EMG. Generic cuff exercises frequently fail when the scapular component is ignored.
Diagnosis is purely clinical and free: inspection, the scapular dyskinesis test, SAT and SRT. Home-based stretching (pectoralis minor, posterior capsule) and closed-chain wall exercises require no equipment.
Common in repetitive overhead workers (painters, electricians, assembly) worldwide. Management is functional rehabilitation and ergonomic modification, not surgery.
Controversies & Areas of Uncertainty
Whether dyskinesis is a primary driver of shoulder pathology or a secondary adaptation remains unresolved. The 2013 Scapular Summit concluded it is best regarded as a potential impairment rather than a discrete diagnosis, and its exact causal role is not clearly defined.
The Kibler I/II/III/IV subtypes have only moderate interrater reliability (kappa around 0.4). Many authorities now favour a binary present vs absent judgement, supplemented by the SAT/SRT corrective tests.
Meta-analysis shows a real but modest 43% relative increase in future shoulder pain. However, a large mixed-sex handball cohort could NOT confirm dyskinesis as an independent risk factor, so it should not be used in isolation to predict injury.
Visual observation is practical but imperfect; 3D motion capture and scapular dyskinesis test scoring improve objectivity but are largely research tools. There is no agreed gold-standard quantitative bedside measure.
MCQ Practice Points
Q: What does the 'C' in SICK Scapula stand for? A: Coracoid Pain. This is due to traction tendinopathy of the tight Pectoralis Minor insertion.
Q: Which muscle weakness is primarily associated with Kibler Type II dyskinesis (Medial Border Prominence)? A: Serratus Anterior weakness (or inhibition) leads to medial border winging.
Q: A positive Scapular Assistance Test (SAT) implies what? A: That scapular dyskinesis is contributing to the patient's impingement symptoms (pain is relieved when the examiner assists motion).
Q: Injury to the Spinal Accessory Nerve results in what type of winging? A: Lateral Winging (Trapezius palsy). The scapula translates laterally and rotates downward. (Contrast with Medial Winging in Long Thoracic/Serratus palsy).
Q: What percentage of energy in the throwing motion is generated by the legs and trunk? A: Approximately 50-55%. Only half is generated by the shoulder/arm.
Exam Viva Scenarios
Practise clinical reasoning and management decisions out loud
“A 22-year-old baseball pitcher presents with anterior shoulder pain and dropping velocity. You diagnose subacromial impingement. On exam, he has a drooped shoulder. Describe your assessment of his scapula.”
“How do you differentiate functional Scapular Dyskinesis from a Long Thoracic Nerve Palsy (True Winging)?”
“Outline your rehabilitation strategy for a swimmer with Type 2 Scapular Dyskinesis.”
The S.I.C.K Scapula
- S: Scapular Malposition
- I: Inferior Medial Prominence
- C: Coracoid Pain
- K: dysKinesis
Kibler Classification
- Type I: Inferior (Ant Tilt)
- Type II: Medial (Int Rot)
- Type III: Superior (Shrug)
- Type IV: Normal
Key Muscles
- Serratus Ant: Weakness = Winging
- Pect Minor: Tightness = Tilt
- Lower Trap: Weakness = Dysfunction
- Upper Trap: Overactivity = Shrug
Management Rules
- NO Surgery (Functional)
- Stretch Pect Minor
- Kinetic Chain (Core/Legs)
- Closed Chain before Open
Evidence Base
SICK Scapula / Disabled Throwing Shoulder Part III
- Defined the SICK scapula syndrome (Scapular malposition, Inferior medial border prominence, Coracoid pain, dysKinesis)
- Linked scapular dysfunction to glenohumeral injury in overhead throwers
- Established the kinetic-chain rehabilitation framework
2013 Scapular Summit Consensus
- Dyskinesis is present in a high percentage of shoulder injuries but is an impairment, not a stand-alone diagnosis
- Impingement symptoms are particularly affected by dyskinesis
- A reliable observational (yes/no) clinical method is available, and scapular rehabilitation is effective within a comprehensive programme
Reliability of Qualitative Classification
- Tested the four-pattern visual classification of scapular dysfunction
- Interrater reliability kappa = 0.4 (moderate); intrarater kappa = 0.5
- Modest reliability later led to a Yes/No (present-absent) observational method
Scapular Dyskinesis and Future Shoulder Pain
- Pooled 5 prospective studies (419 athletes)
- Baseline dyskinesis carried a 43% greater risk of future shoulder pain (RR 1.43, 95% CI 1.05-1.93)
- 35% of athletes with dyskinesis vs 25% without developed pain at 9-24 months
Kinetic Chain Rehabilitation
- Described the proximal-to-distal kinetic-link model for shoulder rehabilitation
- Energy and force are generated in the legs and trunk and transmitted through the scapula to the arm
- Closed-chain and integrated movement patterns activate weakened shoulder musculature
Pectoralis Minor Length and Scapular Kinematics
- 50 asymptomatic volunteers grouped by pectoralis minor resting length
- Short pectoralis minor was associated with persistent anterior tipping and increased internal rotation of the scapula
- These kinematics mirror those seen in subacromial impingement