High Yield Overview

FLOATING SHOULDER - SSSC DISRUPTION

Ipsilateral Clavicle + Glenoid/Scapula Neck | Double Disruption SSSC | Operative if Displaced

2Disruptions to SSSC ring required

15%Of scapula fractures have ipsilateral clavicle

25mmClavicle shortening threshold

1cmGlenoid medialization threshold

SSSC CONCEPT

Single Break

PatternOne SSSC disruption

TreatmentUsually stable - nonoperative

Double Break

PatternTrue floating shoulder

TreatmentUnstable - consider fixation

Triple Break

PatternMassive instability

TreatmentSurgical stabilization required

Critical Must-Knows

Double disruption of SSSC creates floating shoulder (unstable)
SSSC ring: clavicle → AC joint → acromion → spine → glenoid neck → CC ligaments → clavicle
Fix the clavicle first - often restores alignment without direct scapula fixation
Glenoid medialization over 1cm or angular deformity over 40° indicates instability
High-energy mechanism - always assess for associated injuries (pulmonary, brachial plexus)

Examiner's Pearls

"
True floating shoulder requires TWO disruptions of the SSSC
"
Clavicle fixation alone may restore scapula alignment (indirect reduction)
"
GPA (Glenopolar Angle) under 20° indicates significant deformity
"
Associated with high-energy trauma - 80% have additional injuries

Clinical Imaging

Imaging Gallery

Six-panel case series showing pre-operative clavicle fracture (panels A-C) and post-operative plate fixation (panels D-E) with clinical outcome photo (panel F) - demonstrates clavicle-first fixation s — Six-panel case series showing pre-operative clavicle fracture (panels A-C) and post-operative plate fixation (panels D-E) with clinical outcome photo Credit: Source article via PMC via Open-i (NIH) (Open Access (CC BY))

Chest X-ray showing displaced mid-shaft clavicle fracture with clear visualization of shoulder girdle - essential imaging for identifying double SSSC disruption pattern in floating shoulder — Chest X-ray showing displaced mid-shaft clavicle fracture with clear visualization of shoulder girdle - essential imaging for identifying double SSSC Credit: Source article via PMC via Open-i (NIH) (Open Access (CC BY))

Acute trauma chest radiograph from resuscitation setting showing shoulder girdle injury - emphasizes high-energy polytrauma context where 80% have associated injuries — Acute trauma chest radiograph from resuscitation setting showing shoulder girdle injury - emphasizes high-energy polytrauma context where 80% have assCredit: Wikimedia Commons contributor via Wikimedia Commons (CC BY-SA 3.0)

Critical Floating Shoulder Exam Points

Define SSSC Ring

Superior Shoulder Suspensory Complex is a bone-ligament ring: clavicle → AC joint → acromion → scapula spine → glenoid neck → coracoclavicular ligaments → back to clavicle. Two disruptions = floating shoulder.

Clavicle First Strategy

Fixing the clavicle alone often restores scapula alignment indirectly through intact CC ligaments. Assess post-clavicle fixation alignment before deciding on scapula surgery.

Assess Displacement

Key thresholds: clavicle shortening over 25mm, glenoid medialization over 1cm, GPA under 20°, angular deformity over 40°. Displacement indicates instability requiring fixation.

High-Energy Pattern

80% have associated injuries: rib fractures, pneumothorax, brachial plexus injury, head injury. Complete trauma workup mandatory. Often presents in polytrauma setting.

At a Glance - Management Decision

Pattern	SSSC Disruptions	Stability	Treatment
Isolated clavicle fracture	One	Stable	Nonoperative or selective fixation
Isolated scapula neck fracture	One	Stable	Nonoperative (sling, early ROM)
Minimally displaced floating shoulder	Two	Borderline	Consider clavicle fixation alone
Displaced floating shoulder	Two	Unstable	Clavicle fixation, reassess scapula
Severely displaced both bones	Two or more	Grossly unstable	Fix clavicle AND scapula

Mnemonic

CAGESSSSC Ring Components

Clavicle

Medial strut of the ring

AC joint and Acromion

Superior linkage

Glenoid neck

Lateral strut supporting humeral head

Extra-articular scapula spine

Posterior connection

Strong CC ligaments

Coracoclavicular ligaments complete the ring

Memory Hook:The shoulder lives in a CAGE - break two bars and it floats free!

Mnemonic

FLOATFloating Shoulder Assessment

Fracture pattern

Identify both SSSC disruptions

Look for displacement

Shortening, angulation, medialization

Other injuries

Pulmonary, brachial plexus, ribs, head

Assess GPA

Glenopolar angle (normal 30-45°)

Treatment strategy

Clavicle first, then reassess

Memory Hook:When the shoulder FLOATs, follow this systematic assessment!

Mnemonic

DIMSIndications for Scapula Fixation

Displacement over 1cm

Glenoid medialization

Intra-articular extension

Glenoid articular involvement

Malangulation over 40°

Angular deformity

Shortened GPA under 20°

Severely altered mechanics

Memory Hook:DIMS your chances if you miss these indications for surgery!

Overview and Epidemiology

Floating shoulder describes the combination of ipsilateral clavicle and scapula neck (or glenoid) fractures that result in the loss of the bony connection between the axial skeleton and the upper extremity. The term was first coined by Ganz and Noesberger in 1975.

Mechanism of injury:

High-energy direct trauma to the shoulder (MVA, fall from height, motorcycle accidents)
Force applied to the lateral aspect of the shoulder
Axial loading through the humeral head
Sequential failure of SSSC components

True vs Biomechanical Floating Shoulder

True floating shoulder requires disruption of BOTH superior AND inferior limbs of the SSSC. The biomechanical floating shoulder described by Goss requires disruption at two points creating instability. Not all combined clavicle-scapula fractures are unstable - intact CC ligaments may maintain stability.

Associated injuries (high-energy mechanism):

Pulmonary: rib fractures (50%), pneumothorax, pulmonary contusion
Neurological: brachial plexus injury (5-10%), head injury
Vascular: subclavian/axillary injury (rare but devastating)
Other: spine injuries, abdominal trauma

Anatomy and Biomechanics

Superior Shoulder Suspensory Complex (SSSC)

The SSSC is a bone-soft tissue ring that suspends the upper extremity from the axial skeleton. Understanding this concept is fundamental to managing floating shoulder injuries.

SSSC Ring Components:

The ring consists of:

Clavicle - medial strut
AC joint - connects clavicle to acromion
Acromion process - superior link
Scapula spine - posterior connection
Scapula body/glenoid neck - lateral strut
Coracoid process - inferior link
Coracoclavicular ligaments - completes the ring to clavicle

SSSC Superior vs Inferior Struts

Strut	Components	Function
Superior strut	Clavicle, AC joint, acromion	Primary link to axial skeleton
Inferior strut	Coracoid, CC ligaments, glenoid neck	Secondary support, vertical stability

Biomechanical principles:

Ring Stability Concept

Like a pelvic ring, the SSSC requires two disruptions to create instability. A single break (isolated clavicle OR isolated scapula neck) typically remains stable. Two breaks create a floating segment that can displace under the pull of attached muscles.

Deforming forces on the scapula:

Serratus anterior: protracts scapula
Pectoralis minor: tilts glenoid inferiorly
Gravity and arm weight: causes medialization
Trapezius/levator: elevate medial scapula (if intact)

Why the clavicle matters:

The clavicle is the only bony connection between upper limb and axial skeleton
Through intact CC ligaments, fixing the clavicle can indirectly reduce the scapula
Restores the strut function supporting the shoulder

Classification Systems

Goss Classification (1993) - Based on SSSC disruptions

Type	Description	Stability
Single disruption	One break in SSSC ring	Stable
Double disruption	Two breaks in ring (floating shoulder)	Potentially unstable
Triple disruption	Three or more breaks	Unstable

Key concept: The degree of instability depends on:

Number of disruptions
Displacement at each site
Integrity of remaining structures

Classic Double Disruption Patterns

Clavicle fracture + scapula neck fracture (most common)
Clavicle fracture + AC dislocation + glenoid fracture
AC dislocation + coracoid fracture + scapula neck fracture

Clinical Assessment

History

Mechanism: High-energy trauma (MVA, fall from height)
Associated injuries: chest pain, dyspnea, head injury
Hand dominance
Occupation and functional demands
Comorbidities affecting healing

Examination

Inspection: swelling, deformity, skin tenting
Palpation: clavicle, acromion, scapula spine
ROM: usually severely limited by pain
Neurovascular: brachial plexus exam essential
Chest: auscultate for pneumothorax

Neurovascular Assessment

Brachial plexus injury occurs in 5-10% of floating shoulder injuries. Test:

C5: shoulder abduction, biceps
C6: wrist extension, brachioradialis
C7: elbow extension, triceps
C8/T1: finger flexion and intrinsics
Axillary nerve: regimental badge sensation, deltoid

Physical examination findings:

Shortened, drooping shoulder appearance
Visible or palpable clavicle deformity
Ecchymosis over shoulder girdle
Scapula body may be palpable posteriorly
Inability to actively elevate arm

Associated injury screening:

Chest: breath sounds, chest wall tenderness
Neurology: complete brachial plexus exam
Vascular: pulses, capillary refill, expanding hematoma

Investigations

Acute trauma chest radiograph from resuscitation bay showing floating shoulder — Acute trauma presentation of floating shoulder: chest radiograph obtained in the resuscitation bay (marked 'RESUS') demonstrating left shoulder girdle injury with visible clavicle fracture. This image captures the reality of floating shoulder in clinical practice - these are HIGH-ENERGY injuries occurring in polytrauma patients during emergency stabilization, not isolated fractures. The emergency setting emphasizes that floating shoulder is a marker of severe trauma requiring systematic assessment for life-threatening associated injuries. Studies show 80% of floating shoulders have concurrent injuries including pneumothorax (15-30%), hemothorax, multiple rib fractures, brachial plexus injury (10-15%), and head trauma. The chest radiograph is the FIRST imaging study obtained in trauma resuscitation and may simultaneously reveal the clavicle fracture, rib fractures, pulmonary injury, and scapular pathology that defines the SSSC double disruption. This underscores the importance of comprehensive trauma protocols rather than isolated orthopaedic management.Credit: Wikimedia Commons contributor via Wikimedia Commons (CC BY-SA 3.0)

Chest X-ray showing displaced clavicle fracture for SSSC assessment — Chest radiograph (AP view) demonstrating displaced mid-shaft clavicle fracture with comminution. This standard trauma imaging view allows simultaneous visualization of the clavicle and scapula - CRITICAL for identifying the double disruption of the Superior Shoulder Suspensory Complex (SSSC) that defines floating shoulder. The chest X-ray provides the global view necessary to assess: (1) clavicle fracture pattern and displacement, (2) scapular body and neck integrity, (3) associated rib fractures suggesting high-energy mechanism, and (4) pulmonary complications. On this image, the displaced clavicle fracture is clearly visible, and the scapula outline can be assessed for ipsilateral injury. When both clavicle and scapula (specifically glenoid neck, coracoid, or acromion) fractures are present, the SSSC ring is broken in TWO places, creating the unstable 'floating' segment. The chest radiograph is therefore not just for pulmonary assessment - it's the essential screening tool for SSSC integrity and guides the need for dedicated shoulder series and CT imaging.Credit: Source article via PMC via Open-i (NIH) (Open Access (CC BY))

AP shoulder radiograph showing floating shoulder with clavicle and scapula fractures — Floating shoulder injury sustained in a motorcycle accident: AP shoulder radiograph demonstrating concurrent clavicular fracture (15-B2 by AO classification) and scapular fracture (14-A3.1). The combination of these two injuries disconnects the glenoid from the axial skeleton, creating the characteristic 'floating' segment that may require surgical stabilization.Credit: Gilde AK et al., J Orthop Traumatol - PMC4559540 (CC-BY)

3D CT reconstruction showing comminuted scapular fracture pattern — 3D CT reconstruction demonstrating a comminuted scapular fracture (Ideberg type V pattern) with involvement of the glenoid articular surface. The posterior view shows the complexity of the fracture pattern with multiple fragments. 3D reconstructions are invaluable for surgical planning, allowing visualization of fracture lines, fragment displacement, and plate positioning.Credit: Jiménez-Martín A et al., Int J Shoulder Surg - PMC3157100 (CC-BY)

Imaging Protocol

InitialPlain Radiographs

AP chest: pulmonary injury, rib fractures
AP clavicle: assess shortening, displacement
Scapular Y view: glenoid position, GPA measurement
Axillary lateral: glenoid articular surface
AP shoulder: glenohumeral relationship

DefinitiveCT Scan

3D reconstruction: fracture pattern, displacement
Glenoid articular involvement: size, displacement
Scapula neck displacement: medialization measurement
Surgical planning: plate contouring, screw trajectories

If indicatedAdditional Studies

CT angiography: if vascular injury suspected
MRI: brachial plexus injury (subacute)
EMG/NCS: delayed brachial plexus assessment

Key measurements on imaging:

Radiographic Measurements

Measurement	Method	Significance
Glenopolar Angle	Angle between glenoid axis and scapula body on Y view	Under 20° = significant deformity
Medialization	Distance glenoid has shifted medially on CT	Over 1cm = operative indication
Angular deformity	Angulation of glenoid neck relative to body	Over 40° = instability
Clavicle shortening	Compare to contralateral or measure displacement	Over 25mm = consider fixation

Management Algorithm

Key Decision Points:

Management Algorithm

PatternStep 1: Assess SSSC Disruption

Count number of disruptions
Single disruption: usually stable, nonoperative
Double disruption: assess displacement

SeverityStep 2: Measure Displacement

GPA, medialization, angulation, clavicle shortening
Minimally displaced: consider nonoperative or clavicle alone
Significantly displaced: surgical stabilization

Surgical StrategyStep 3: Fix Clavicle First

Plate fixation of clavicle
Intraoperative fluoro of scapula
Reassess scapula alignment after clavicle fixation

Second StageStep 4: Decide on Scapula

If alignment restored: stop
If persistent displacement: proceed to scapula ORIF

Clavicle First Strategy Rationale

Fixing the clavicle restores the strut function of the SSSC. Through intact CC ligaments, this can indirectly reduce the scapula. Studies show clavicle fixation alone achieves acceptable alignment in 60-70% of floating shoulders.

Surgical Technique

Complete surgical case series showing clavicle fixation for floating shoulder — Complete surgical case demonstrating the 'CLAVICLE FIRST' strategy for floating shoulder management. This six-panel series shows: **Pre-operative imaging (panels A-C)**: AP chest view (A), shoulder AP (B), and oblique view (C) demonstrating clavicle fracture with displacement and assessment of the scapula - these multiple radiographic angles are essential for understanding the three-dimensional SSSC disruption pattern. **Post-operative fixation (panels D-E)**: AP and oblique views showing anatomical plate and screw fixation of the clavicle achieving restoration of clavicle length and alignment. Note that NO scapula fixation was performed - the clavicle fixation ALONE restored SSSC stability through the intact coracoclavicular ligaments. **Clinical outcome (panel F)**: Posterior view photograph demonstrating symmetrical shoulder contour and functional alignment after treatment. This case illustrates the fundamental principle: **fix the clavicle first, then reassess**. In many floating shoulders, clavicle fixation provides INDIRECT reduction of scapular displacement, avoiding the need for technically demanding scapula surgery. The surgical goals shown here include: (1) restoring clavicle length (preventing over 25mm shortening), (2) achieving stable plate fixation (minimum 3 screws per fragment), (3) reassessing SSSC stability intraoperatively with fluoroscopy, and (4) proceeding to scapula fixation ONLY if displacement persists (GPA under 20°, medialization over 1cm). This stepwise approach minimizes surgical morbidity while achieving excellent functional outcomes.Credit: Source article via PMC via Open-i (NIH) (Open Access (CC BY))

Positioning:

Beach chair or supine with bump
Entire shoulder girdle in field
Image intensifier available for scapula assessment

Approach:

Standard anterior or superior approach to clavicle
Protect supraclavicular nerves
Identify fracture pattern

Fixation:

Superior plating: 3.5mm reconstruction or precontoured plate
Anteroinferior plating: biomechanically stronger
3 screws each side of fracture minimum
Lag screws for butterfly fragments

Intraoperative Assessment:

Fluoro scapular Y view after clavicle fixation
Measure GPA, medialization
If acceptable → close
If persistent displacement → proceed to scapula

Why Anteroinferior Plating?

Anteroinferior plate position is biomechanically superior for clavicle shaft fractures - resists bending forces better and has lower profile reducing hardware prominence.

Complications

Complications of Floating Shoulder

Complication	Incidence	Risk Factors	Management
Malunion	10-20%	Nonoperative displaced, inadequate fixation	Osteotomy if symptomatic
Nonunion	5-10%	Smoking, comminution, inadequate fixation	Revision ORIF with bone graft
Shoulder stiffness	15-25%	Prolonged immobilization, adhesive capsulitis	Physiotherapy, manipulation, arthroscopy
Brachial plexus injury	5-10%	High-energy mechanism, severe displacement	Observation, exploration if no recovery
Hardware prominence (clavicle)	10-20%	Superior plate position, thin patients	Hardware removal after union
Suprascapular nerve injury	Less than 5%	Surgical approach, direct injury	Observation, nerve release if no recovery

Outcome-related factors:

Good Prognostic Factors

Anatomic reduction achieved
Single surgery (clavicle alone)
Early mobilization
Younger patient
Isolated injury (no polytrauma)

Poor Prognostic Factors

Persistent glenoid malposition
Intra-articular involvement
Associated brachial plexus injury
Delayed treatment
Polytrauma, ICU admission

Postoperative Care

Rehabilitation Protocol

0-2 weeksPhase 1: Protection

Sling immobilization
Wound care
Gentle pendulum exercises
Elbow, wrist, hand ROM

2-6 weeksPhase 2: Early Motion

Passive and active-assisted ROM
Forward flexion, external rotation in plane of scapula
Avoid combined abduction/external rotation
Continue sling when not exercising

6-12 weeksPhase 3: Active ROM

Discontinue sling
Full active ROM progression
Begin isometric strengthening
Scapular stabilization exercises

12-16 weeksPhase 4: Strengthening

Progressive resistance exercises
Rotator cuff strengthening
Sport-specific training if applicable
Return to non-contact activities

4-6 monthsPhase 5: Return to Activity

Full strength and ROM
Contact sports cleared
Manual labor cleared
Hardware removal if symptomatic (after 1 year)

Outcomes and Prognosis

Factors affecting outcome:

Outcome by Treatment

Treatment	Union Rate	Functional Outcome	Complications
Nonoperative (displaced)	85-90%	Fair to good	Malunion, weakness common
Clavicle fixation alone	95%	Good to excellent	Hardware prominence
Combined clavicle + scapula	95%	Good to excellent	Longer surgery, nerve risk

Long-term Outcomes

Studies show operatively treated floating shoulder patients achieve Constant scores of 80-90% of contralateral side. Most return to pre-injury activity level. Residual weakness is more common with nonoperative treatment of displaced injuries.

Evidence Base

Systematic Review: Floating Shoulder Treatment

Level III

Dombrowsky et al. • J Orthop Trauma (2020)

Key Findings:

78 studies, 723 patients reviewed
Operative treatment showed better functional outcomes
Clavicle fixation alone often sufficient
Combined fixation for persistent displacement

Clinical Implication: Operative treatment preferred for displaced double disruptions. Clavicle-first strategy reduces need for scapula surgery.

Outcomes of Surgical Management

Level IV

Goss and Owens • J Bone Joint Surg Am (2006)

Key Findings:

Double SSSC disruption creates instability
Clavicle fixation restores strut function
GPA under 20° associated with poor outcomes
Early surgery recommended

Clinical Implication: Understanding SSSC concept guides treatment. Clavicle fixation is key to restoring shoulder mechanics.

Glenopolar Angle as Predictor

Level IV

Romero et al. • J Shoulder Elbow Surg (2001)

Key Findings:

GPA under 20° correlates with poor function
Medialization over 1cm affects strength
Angular deformity affects scapulothoracic motion
Radiographic parameters guide surgery

Clinical Implication: GPA under 20° is surgical indication. Use radiographic measurements to guide treatment decisions.

Operative vs Nonoperative Treatment

Level III

Cole et al. • J Shoulder Elbow Surg (2012)

Key Findings:

Operative group showed better DASH scores
Higher return to work rate with surgery
Nonoperative acceptable for minimally displaced
Displaced injuries benefit from surgery

Clinical Implication: Reserve nonoperative treatment for minimally displaced injuries or medically unfit patients.

Clavicle Alone vs Combined Fixation

Level IV

van Noort and van Kampen • Arch Orthop Trauma Surg (2005)

Key Findings:

Clavicle fixation alone successful in majority
Combined fixation for persistent instability
Assess scapula intraoperatively after clavicle
Avoid unnecessary scapula surgery

Clinical Implication: Fix clavicle first and reassess. Combined fixation only when scapula remains significantly displaced.

Exam Viva Scenarios

Practice these scenarios to excel in your viva examination

VIVA SCENARIOStandard

Scenario 1: Classic Floating Shoulder

EXAMINER

"A 35-year-old male motorcyclist presents after high-speed accident. X-rays show a displaced mid-shaft clavicle fracture and an ipsilateral scapula neck fracture. He has no neurovascular deficit. How would you assess and manage this patient?"

EXCEPTIONAL ANSWER

Thank you. This patient has a floating shoulder injury with ipsilateral clavicle and scapula fractures. I would approach this systematically. **Assessment:** First, I would complete my trauma assessment given the high-energy mechanism, looking specifically for pulmonary injury, brachial plexus injury, and other associated injuries. Clinically, I would examine for neurovascular status including a full brachial plexus examination. **Imaging:** I would obtain AP clavicle, true scapular Y view, and axillary lateral radiographs. I would also request a CT scan with 3D reconstruction to characterize the fracture patterns and measure displacement parameters including the glenopolar angle. **Classification:** This represents a double disruption of the Superior Shoulder Suspensory Complex. The key is determining stability - I would measure GPA (surgical threshold is less than 20°), glenoid medialization (threshold greater than 1cm), and clavicle shortening (threshold greater than 25mm). **Management:** My treatment strategy would be to fix the clavicle first. Through plate fixation of the clavicle, I restore the strut function of the SSSC. Intraoperatively, after clavicle fixation, I would obtain fluoroscopic scapular Y views to reassess the scapula position. If the GPA and medialization are acceptable, I would stop there. If persistent significant displacement, I would proceed to scapula fixation via a posterior Judet approach. I would counsel the patient about the rehabilitation protocol, expected outcomes of 80-90% good results with surgery, and potential complications including stiffness and hardware prominence.

KEY POINTS TO SCORE

Define SSSC and double disruption concept

Know radiographic thresholds: GPA under 20°, medialization over 1cm

Clavicle-first strategy with intraoperative reassessment

Posterior Judet approach for scapula if needed

COMMON TRAPS

✗Forgetting to assess for associated injuries

✗Not recognizing this as a double SSSC disruption

✗Operating on scapula without assessing after clavicle fixation

LIKELY FOLLOW-UPS

"How would you perform the Judet approach?"

"What nerve is at risk during posterior scapula approach?"

"What if CT shows significant glenoid articular involvement?"

VIVA SCENARIOChallenging

Scenario 2: Minimally Displaced Pattern

EXAMINER

"A 55-year-old female falls from standing height onto her shoulder. X-rays show a minimally displaced mid-shaft clavicle fracture (10mm shortening) and an ipsilateral scapula neck fracture with GPA of 32°. She is a low-demand patient. How would you manage this?"

EXCEPTIONAL ANSWER

Thank you. This patient has a floating shoulder pattern but with minimal displacement. Let me assess whether this actually represents an unstable injury requiring surgery. **Assessment:** The key measurements are reassuring - clavicle shortening of only 10mm (threshold is greater than 25mm) and GPA of 32° (threshold is under 20°). These suggest a relatively stable pattern despite the double disruption. **Decision-making:** In this low-demand patient with minimally displaced fractures, nonoperative management is reasonable. The SSSC ring is disrupted at two points, but the displacement is insufficient to cause mechanical instability. **Treatment plan:** I would manage this nonoperatively with: - Sling immobilization for 2-4 weeks - Early pendulum exercises starting at 1-2 weeks - Progressive ROM at 3-4 weeks - Strengthening at 6-8 weeks **Monitoring:** I would see her at 2 weeks for clinical and radiographic review to ensure no secondary displacement. If there is progressive collapse, I would reconsider operative management. **Counseling:** I would explain that while surgical treatment generally provides more predictable results, her minimal displacement and low demands make nonoperative treatment appropriate. She may have some residual cosmetic deformity from clavicle malunion but functional outcome should be satisfactory. **Follow-up:** Serial X-rays at 2, 6, and 12 weeks to confirm union. Return to activity at 3-4 months.

KEY POINTS TO SCORE

Know displacement thresholds for surgical intervention

Low-demand patients may tolerate some malposition

Monitor for secondary displacement

Explain trade-offs of nonoperative vs operative treatment

COMMON TRAPS

✗Recommending surgery for all floating shoulders

✗Not measuring GPA and displacement parameters

✗Failing to arrange adequate follow-up for nonoperative cases

LIKELY FOLLOW-UPS

"What if she was a manual laborer?"

"What would change your mind to operate?"

"How do you measure glenopolar angle?"

VIVA SCENARIOCritical

Scenario 3: Persistent Displacement After Clavicle

EXAMINER

"You have fixed a displaced clavicle fracture as part of a floating shoulder. Intraoperative fluoroscopy shows the GPA is now 15° and there is 15mm glenoid medialization. How do you proceed?"

EXCEPTIONAL ANSWER

Thank you. This represents a floating shoulder where clavicle fixation alone has not adequately restored scapula position. The GPA of 15° is below the 20° threshold and medialization of 15mm exceeds the 1cm threshold, indicating persistent significant displacement. **Decision:** I need to proceed with scapula fixation in this same sitting if the patient is stable enough for the additional surgery. **Repositioning:** I would reposition the patient to lateral decubitus position with the affected side up. The arm is draped free to allow intraoperative ROM assessment. **Judet Approach:** I would use a posterior Judet approach: - Incision along the scapula spine extending down the lateral border - Develop the interval between infraspinatus and deltoid - Protect the suprascapular nerve at the spinoglenoid notch - Expose the lateral border and glenoid neck **Reduction and Fixation:** - Reduce the glenoid neck fracture under direct vision - Use pointed reduction clamps - Fix with a 3.5mm reconstruction plate along the lateral border - Add smaller plate to spine if involved - Confirm GPA restoration on fluoro **Assessment:** After fixation, I would confirm: - GPA restored to over 30° - Medialization corrected - Shoulder ROM through a functional arc without crepitus **Postoperative plan:** Standard rehabilitation protocol with protection for 2 weeks, early passive ROM, progressive strengthening after 6 weeks. The key learning point is that approximately 30-40% of floating shoulders require combined fixation - the clavicle-first strategy identifies which cases need both.

KEY POINTS TO SCORE

Know thresholds triggering scapula fixation

Judet approach landmarks and technique

Protect suprascapular nerve at spinoglenoid notch

Lateral border plate fixation principles

COMMON TRAPS

✗Closing without addressing persistent displacement

✗Not knowing the posterior approach to scapula

✗Forgetting suprascapular nerve protection

LIKELY FOLLOW-UPS

"What are the boundaries of the Judet approach?"

"How would you manage an associated glenoid fracture?"

"What if patient becomes unstable - would you stage?"

MCQ Practice Points

MCQ #1: SSSC Components

Q: Which structure is NOT part of the Superior Shoulder Suspensory Complex?

A) Clavicle B) Coracoacromial ligament C) Coracoclavicular ligaments D) Acromion

A: B - The coracoacromial ligament connects coracoid to acromion but is not part of the SSSC ring. The SSSC includes: clavicle, AC joint, acromion, scapula spine, glenoid neck, coracoid, and CC ligaments.

MCQ #2: Surgical Threshold

Q: What glenopolar angle represents a surgical threshold in floating shoulder?

A) Less than 40° B) Less than 30° C) Less than 20° D) Less than 10°

A: C - GPA under 20° indicates significant angular deformity and is a surgical indication. Normal GPA is 30-45°.

MCQ #3: Treatment Strategy

Q: In the management of floating shoulder, the recommended initial surgical strategy is:

A) Fix scapula first, then assess clavicle B) Fix clavicle first, then assess scapula C) Always fix both clavicle and scapula D) Fix whichever has more displacement

A: B - Clavicle-first strategy is recommended. Fixing the clavicle restores the strut function and through intact CC ligaments often reduces the scapula indirectly. Assess scapula position after clavicle fixation.

MCQ #4: At-Risk Structure

Q: Which nerve is at risk during posterior approach to the scapula?

A) Axillary nerve B) Long thoracic nerve C) Suprascapular nerve D) Musculocutaneous nerve

A: C - The suprascapular nerve is at risk at the spinoglenoid notch during posterior scapula approaches. Injury causes infraspinatus weakness.

MCQ #5: Associated Injuries

Q: What percentage of floating shoulder injuries have associated injuries due to high-energy mechanism?

A) 40% B) 60% C) 80% D) 95%

A: C - Approximately 80% of floating shoulder injuries have associated injuries including rib fractures, pneumothorax, brachial plexus injury, or head trauma due to the high-energy mechanism.

MCQ #6: Displacement Threshold

Q: What degree of glenoid medialization is considered a surgical indication in floating shoulder?

A) Greater than 5mm B) Greater than 1cm C) Greater than 2cm D) Greater than 3cm

A: B - Glenoid medialization greater than 1cm is a surgical indication. Other thresholds include GPA under 20° and angular deformity over 40°.

Australian Context

Floating shoulder injuries in Australia typically occur in the context of high-energy trauma, most commonly motor vehicle accidents and motorcycle crashes. These patients often present to Level 1 trauma centres and may require multidisciplinary care in the polytrauma setting.

Australian orthopaedic practice generally follows the clavicle-first operative strategy for displaced floating shoulder injuries. The availability of CT scanning for surgical planning is standard in major centres, and intraoperative fluoroscopy is used to assess scapula alignment after clavicle fixation.

Documentation of neurovascular status is particularly important given the association with brachial plexus injury. Medicolegal considerations include thorough consent discussing the potential for staged procedures, expected functional outcomes, and the possibility of residual weakness or stiffness.

Return to work timelines vary based on occupation - sedentary workers may return at 6-8 weeks, while heavy manual labourers typically require 4-6 months of recovery.

FLOATING SHOULDER

High-Yield Exam Summary

Definition & SSSC

•Double disruption of SSSC = floating shoulder
•SSSC ring: clavicle → AC joint → acromion → spine → glenoid → CC ligaments
•Single disruption = stable, double = potentially unstable
•15% of scapula fractures have ipsilateral clavicle fracture

Key Measurements

•GPA normal 30-45°, surgical threshold under 20°
•Medialization surgical threshold over 1cm
•Angular deformity surgical threshold over 40°
•Clavicle shortening threshold over 25mm

Management Algorithm

•Step 1: Assess SSSC disruptions and displacement
•Step 2: Fix clavicle first (plate fixation)
•Step 3: Intraop fluoro to reassess scapula
•Step 4: If persistent displacement → scapula ORIF
•Clavicle alone restores alignment in 60-70%

Surgical Approaches

•Clavicle: anterior/superior approach, plate fixation
•Scapula: Judet posterior approach
•Judet: between deltoid and infraspinatus
•Protect suprascapular nerve at spinoglenoid notch

Complications

•Malunion 10-20% (especially nonoperative)
•Stiffness 15-25%
•Brachial plexus injury 5-10%
•Hardware prominence with clavicle plate
•Suprascapular nerve injury with scapula surgery

Pattern

SSSC Disruptions

Stability

Treatment

Isolated clavicle fracture

One

Stable

Nonoperative or selective fixation

Isolated scapula neck fracture

One

Stable

Nonoperative (sling, early ROM)

Minimally displaced floating shoulder

Two

Borderline

Consider clavicle fixation alone

Displaced floating shoulder

Two

Unstable

Clavicle fixation, reassess scapula

Severely displaced both bones

Two or more

Grossly unstable

Fix clavicle AND scapula

Strut

Components

Function

Superior strut

Clavicle, AC joint, acromion

Primary link to axial skeleton

Inferior strut

Coracoid, CC ligaments, glenoid neck

Secondary support, vertical stability

Type

Description

Stability

Single disruption

One break in SSSC ring

Stable

Double disruption

Two breaks in ring (floating shoulder)

Potentially unstable

Triple disruption

Three or more breaks

Unstable

Measurement

Method

Significance

Glenopolar Angle

Angle between glenoid axis and scapula body on Y view

Under 20° = significant deformity

Medialization

Distance glenoid has shifted medially on CT

Over 1cm = operative indication

Angular deformity

Angulation of glenoid neck relative to body

Over 40° = instability

Clavicle shortening

Compare to contralateral or measure displacement

Over 25mm = consider fixation

Positioning:

Beach chair or supine with bump
Entire shoulder girdle in field
Image intensifier available for scapula assessment

Approach:

Standard anterior or superior approach to clavicle
Protect supraclavicular nerves
Identify fracture pattern

Fixation:

Superior plating: 3.5mm reconstruction or precontoured plate
Anteroinferior plating: biomechanically stronger
3 screws each side of fracture minimum
Lag screws for butterfly fragments

Intraoperative Assessment:

Fluoro scapular Y view after clavicle fixation
Measure GPA, medialization
If acceptable → close
If persistent displacement → proceed to scapula

Why Anteroinferior Plating?

Anteroinferior plate position is biomechanically superior for clavicle shaft fractures - resists bending forces better and has lower profile reducing hardware prominence.

Complication

Incidence

Risk Factors

Management

Malunion

10-20%

Nonoperative displaced, inadequate fixation

Osteotomy if symptomatic

Nonunion

5-10%

Smoking, comminution, inadequate fixation

Revision ORIF with bone graft

Shoulder stiffness

15-25%

Prolonged immobilization, adhesive capsulitis

Physiotherapy, manipulation, arthroscopy

Brachial plexus injury

5-10%

High-energy mechanism, severe displacement

Observation, exploration if no recovery

Hardware prominence (clavicle)

10-20%

Superior plate position, thin patients

Hardware removal after union

Suprascapular nerve injury

Less than 5%

Surgical approach, direct injury

Observation, nerve release if no recovery

Treatment

Union Rate

Functional Outcome

Complications

Nonoperative (displaced)

85-90%

Fair to good

Malunion, weakness common

Clavicle fixation alone

95%

Good to excellent

Hardware prominence

Combined clavicle + scapula

95%

Good to excellent

Longer surgery, nerve risk

Type	Description	Associated Injury
I	Minimally displaced	Usually isolated
II	Displaced without angular deformity	May have clavicle fracture
III	Displaced with angular deformity	Often floating shoulder

Type	Description	Associated Injury
I	Minimally displaced	Usually isolated
II	Displaced without angular deformity	May have clavicle fracture
III	Displaced with angular deformity	Often floating shoulder

Parameter	Normal	Surgical Threshold
Glenopolar angle (GPA)	30-45°	Under 20°
Glenoid medialization	0	Over 1cm
Angular deformity	0	Over 40°
Clavicle shortening	0	Over 25mm

Floating Shoulder Injuries

Floating Shoulder Injuries

FLOATING SHOULDER - SSSC DISRUPTION

SSSC CONCEPT

Critical Must-Knows

Examiner's Pearls

Clinical Imaging

Imaging Gallery

Critical Floating Shoulder Exam Points

Define SSSC Ring

Clavicle First Strategy

Assess Displacement

High-Energy Pattern

At a Glance - Management Decision

CAGESSSSC Ring Components

FLOATFloating Shoulder Assessment

DIMSIndications for Scapula Fixation

Overview and Epidemiology

Anatomy and Biomechanics

Superior Shoulder Suspensory Complex (SSSC)

SSSC Superior vs Inferior Struts

Classification Systems

GPA Measurement

Clinical Assessment

History

Examination

Neurovascular Assessment

Investigations

Imaging Protocol

Radiographic Measurements

Management Algorithm

Management Algorithm

Risk of Nonoperative Treatment

Surgical Technique

Suprascapular Nerve

Complications

Complications of Floating Shoulder

Good Prognostic Factors

Poor Prognostic Factors

Postoperative Care

Rehabilitation Protocol

Outcomes and Prognosis

Outcome by Treatment

Evidence Base

Systematic Review: Floating Shoulder Treatment

Outcomes of Surgical Management

Glenopolar Angle as Predictor

Operative vs Nonoperative Treatment

Clavicle Alone vs Combined Fixation

Exam Viva Scenarios

Scenario 1: Classic Floating Shoulder

Scenario 2: Minimally Displaced Pattern

Scenario 3: Persistent Displacement After Clavicle

MCQ Practice Points

Australian Context

FLOATING SHOULDER

Definition & SSSC

Key Measurements

Management Algorithm

Surgical Approaches

Complications

Floating Shoulder Injuries

Floating Shoulder Injuries

FLOATING SHOULDER - SSSC DISRUPTION

SSSC CONCEPT

Critical Must-Knows

Examiner's Pearls

Clinical Imaging

Imaging Gallery

Critical Floating Shoulder Exam Points

Define SSSC Ring

Clavicle First Strategy

Assess Displacement

High-Energy Pattern

At a Glance - Management Decision

CAGESSSSC Ring Components

FLOATFloating Shoulder Assessment

DIMSIndications for Scapula Fixation

Overview and Epidemiology

Anatomy and Biomechanics