Clavicle ORIF (Midshaft & Distal)

Midshaft Clavicle Fracture (Allman Group I, Edinburgh 2B)

Classification

Allman Classification: Group I = middle third (80% of all clavicle fractures), Group II = distal third (15%), Group III = medial third (5%).

Edinburgh Classification (Robinson 1998, PMID 9619941): Derived from a consecutive series of 1000 adult clavicle fractures; gives more surgical detail than Allman and reports inter-/intra-observer reliability.

• Type 1: Medial fifth
• Type 2A: Diaphyseal (middle), undisplaced (cortical alignment maintained or greenstick)
• 2B1: Displaced diaphyseal, simple or single butterfly fragment
• 2B2: Displaced diaphyseal, comminuted / segmental, no cortical contact
• Type 3: Lateral fifth (3A undisplaced, 3B displaced)

Edinburgh type 2B (displaced diaphyseal) carries the highest risk of delayed/non-union and is the group studied in the operative-versus-non-operative RCTs.

Pivotal RCT Evidence (Midshaft)

Robinson CM et al. JBJS Am 2013;95(17):1576-84 (PMID 24005198): Multicentre, single-blinded RCT of 200 adults aged 16-60 with acute displaced midshaft fractures, randomised to primary plate ORIF vs non-operative (sling). Union confirmed on 3D CT.

Results:

• Non-union: ORIF 1/200 vs non-operative 16/200 (relative risk 0.07, p = 0.007)
• One-year DASH (3.4 vs 6.1, p = 0.04) and Constant (92.0 vs 87.8, p = 0.01) scores favoured ORIF for the whole cohort
• KEY nuance: when patients who developed non-union were excluded, there was NO significant functional difference at any time point — the benefit is essentially prevention of non-union/malunion
• Patients were less dissatisfied with shoulder droop, bump and asymmetry after ORIF
• ORIF was significantly more expensive and carried implant-related complications not seen with non-operative care

Conclusion (authors): ORIF reduces non-union and improves outcomes mainly by preventing non-union; the trial does NOT support routine primary plate fixation for every displaced midshaft fracture, supporting an individualised, shared decision.

Earlier confirmatory RCT — Canadian Orthopaedic Trauma Society (COTS) JBJS Am 2007;89(1):1-10 (PMID 17200303): 132 patients randomised to plate vs sling. Non-union 2/67 (ORIF) vs 7/65 (non-op, p = 0.042); symptomatic malunion 0 vs 9; better Constant/DASH and faster union with ORIF; hardware removal the commonest reason for re-intervention.

Absolute Indications

Relative Indications (Shared Decision-Making)

Non-Operative Management — When to Choose

For undisplaced or minimally displaced midshaft clavicle fractures (Edinburgh 2A), non-operative management remains the standard of care. Broad arm sling for comfort is preferred over figure-of-8 bandage — multiple trials demonstrate equivalent outcomes with the sling and significantly better patient comfort (less axillary skin excoriation, nerve compression).

Expected timeline non-operative: Radiographic union by 12-16 weeks in most adults. Return to light activities 6-8 weeks, sport 12-16 weeks. Counsel patients that a visible bump (exuberant callus) may develop at the fracture site and is a normal healing response — it typically remodels over 12-24 months but may never completely resolve.

Absolute contraindications to non-operative management are the absolute indications listed above. For the remaining displaced fractures (Edinburgh 2B), the RCT data (Robinson 2013, 2007 COTS) supports discussing operative fixation to reduce non-union/malunion, particularly when shortening exceeds 2cm — while acknowledging the Cochrane finding of no clinically important functional gain.

Guidelines, Registries & Global Practice

Clavicle fracture epidemiology: Clavicle fractures account for 2.6-4% of all fractures (Lenza Cochrane 2019; Robinson Edinburgh series). Bimodal age distribution — young males (sport and road trauma) and elderly females (osteoporotic falls). Midshaft (Allman Group I / Edinburgh type 2) approximately 80%, lateral (Group II / type 3) approximately 15%, medial (Group III / type 1) approximately 5%.

International practice variation (side by side): Operative thresholds genuinely differ by region. North American practice (influenced by the 2007 Canadian COTS and 2013 Edinburgh RCTs) has a comparatively higher rate of fixation for displaced fractures. UK BOA/BOAST and much of European practice remains more selective, reserving fixation for absolute indications or markedly displaced/shortened fractures in higher-demand patients, partly reflecting the Cochrane finding (PMID 30666620) that surgery confers no clinically important functional benefit beyond reducing non-union/malunion. No major arthroplasty registry (NJR, AJRR, AOANJRR, SHAR) captures clavicle ORIF volumes, so registry-level implant-survival data are not applicable here; the evidence base is RCT/meta-analysis. For the exam, demonstrate awareness that practice varies across societies and anchor the decision in the RCT and Cochrane evidence rather than any single national guideline.

Relevant Surgical Anatomy — Midshaft Approach

Skin and Subcutaneous Layer

Incision: 1-2cm inferior to palpable clavicle contour, centred over fracture. 8-10cm length for typical midshaft fracture. Alternatively a longitudinal incision directly over the clavicle for anteroinferior approach.

Supraclavicular nerves (C3-C4): Cross from posterior to anterior in subcutaneous fat at the clavicle level. The intermediate branch (supplying skin over anterior chest) and lateral branch (supplying lateral shoulder and upper arm skin) are most at risk. Their transection produces sensory loss over the anterior chest below the incision and lateral shoulder. This is expected and permanent in many patients. Warn explicitly preoperatively.

Clavicle and Periosteum

Shape: S-shaped in the axial plane. Medial two-thirds convex anteriorly, lateral third concave anteriorly. Important for understanding plate contouring requirements.

Cross section: Medial third is roughly tubular; lateral third is flattened in the AP plane. The transition at the middle third (fracture zone) is where comminution typically occurs.

Periosteum: Well defined, elevate carefully to preserve healing biology. Subperiosteal dissection on the superior surface creates the bone-plate interface without entering deep dangerous territory.

Deep Structures (Posterior to Clavicle)

Subclavian vein: Passes posterior to the medial clavicle, immediately deep to the posterior cortex. Most vulnerable during medial fragment reduction and medial screw placement.

Subclavian artery: Passes posterior and slightly inferior to the clavicle, separated from the vein by the anterior scalene muscle at the medial third. Less vulnerable than the vein but still at risk.

Brachial plexus: Posterior to the clavicle and lateral to the subclavian artery. Trunk-level at this point (C5-T1 upper, middle, lower trunks).

Pneumothorax risk: The apex of the lung sits posterior to the medial clavicle. A blind posterior drill through the medial third can penetrate the pleura. Always protect posterior cortex with a curved Hohmann retractor during drilling.

Deltotrapezial Fascia

At the superior surface of the clavicle, the deltoid (anteriorly) and trapezius (posteriorly) insert through periosteum and fascia. Incising and elevating this layer gives the plate-bone interface. It must be repaired during closure over the plate to reduce hardware prominence and infection risk.

Relevant Surgical Anatomy — Distal Clavicle Approach

Coracoclavicular Ligaments

Trapezoid ligament: More lateral, originates on the trapezoid line of the coracoid and inserts on the inferior surface of the distal clavicle trapezoid ridge. Primary restraint to anteroposterior translation.

Conoid ligament: More medial and conical, origin at the coracoid knuckle, inserts on conoid tubercle of clavicle undersurface (approximately 4cm from lateral end). Primary restraint to superior translation of the clavicle relative to the coracoid.

Operative relevance: In Neer IIB, the conoid is either torn or remains on the proximal fragment, leaving only the trapezoid on the distal fragment. The proximal fragment therefore migrates superiorly, driven by trapezius pull. Surgical fixation must control superior translation of the proximal fragment.

Acromioclavicular Joint

Capsule and ligaments: Superior and inferior AC ligaments stabilise the AC joint in the horizontal plane. The superior capsule is strong and thick (most important horizontal stabiliser).

Hook plate approach: The hook passes directly into the subacromial space under the acromion, occupying bursal tissue and ultimately impinging on the undersurface of the acromion and rotator cuff if not removed.

Floating Shoulder — Combined Clavicle and Scapular Neck Fracture

A floating shoulder is the combination of an ipsilateral clavicle fracture and scapular neck fracture, effectively disconnecting the upper limb from the thorax via disruption of the superior shoulder suspensory complex (SSSC). The SSSC comprises the clavicle, AC joint, coracoclavicular ligaments, coracoid process, coracoacromial ligament, and the glenoid process — a ring structure that maintains glenohumeral position.

Operative significance: Two-point disruption of the SSSC (clavicle fracture + scapular neck fracture) is an absolute indication for operative fixation of the clavicle. Restoring clavicle length and alignment indirectly reduces the scapular neck fracture in most cases (clavicle acts as an internal strut). Isolated scapular neck fracture fixation is rarely required once clavicle is plated.

Exam point: Know the SSSC concept — examiners commonly test this as a "what is a floating shoulder and how do you manage it" question.

Midshaft Clavicle ORIF

Patient Position

Beach chair: 30-45 degrees upright. Head support or horseshoe headrest. Bump under ipsilateral scapula. Arm free-draped to allow traction and manipulation. Image intensifier from the head of the table to give AP view of clavicle.

Step 1 — Incision

Superior approach: 1-2cm inferior to palpable clavicle, parallel to bone, centred over fracture. 8-10cm. Incise skin and platysma.

Anteroinferior approach: Longitudinal incision directly over bone, then develop plane on the anterior-inferior surface for plate placement.

Raise subcutaneous flaps. Identify and protect supraclavicular nerve branches (note, not always possible — warn patient preoperatively). Incise deltotrapezial fascia along the superior surface.

Step 2 — Fracture Reduction

Expose fracture fragments by gentle periosteal elevation. Clean haematoma from fracture ends. Reduce length (traction) then angular alignment. Provisional K-wire or reduction clamp.

Comminuted fractures: Lag screw any large butterfly fragment first, then apply plate as neutralisation device. Do NOT strip butterfly fragment of its soft tissue attachments (blood supply).

Step 3 — Plate Application (Superior vs Anteroinferior)

Superior plate: Pre-contour to match clavicle S-shape. Apply to superior surface. 3.5mm LC-DCP or pre-contoured clavicle plate. Minimum 3 bicortical screws each side of fracture (6 cortices). Central hole over fracture or compression hole applied for simple fractures.

Anteroinferior plate: Apply on the anteroinferior surface (anatomic tension side). Requires more dissection, including caution protecting posterior cortex during drilling. Biomechanically superior. Pre-contoured plates available.

Screw placement safety: Always protect posterior cortex with a curved Hohmann retractor before drilling. Measure drill depth precisely. Avoid unicortical screws in medial third (insufficient purchase).

Step 4 — Closure

Repair deltotrapezial fascia over plate with interrupted absorbable sutures. This reduces hardware prominence and irritation. Subcutaneous closure. Skin with running absorbable or subcuticular suture.

Intraoperative Imaging and Quality Assessment

Obtain intraoperative fluoroscopy in at minimum two planes: AP clavicle and 15-degree cephalad tilt (Zanca view equivalent). Confirm:

• Fracture reduced to within 5mm of anatomic length
• All screws contained within bone (no posterior cortex breach on medial screws)
• No screw penetrating the AC joint (distal screws)
• Plate contour matching clavicle S-shape — no gapping or toggling of fixation

If fluoroscopy is unavailable intraoperatively, portable plain radiograph in recovery room before patient wakes is the minimum acceptable check.

Plate Contouring — Key Technical Point

The clavicle has a double curvature — medial convexity anteriorly, lateral concavity anteriorly (the S-shape). Pre-contoured plates approximate this, but further intraoperative contouring with bending irons is almost always required for the individual patient's anatomy. A poorly contoured plate will toggle with loading, increasing the risk of screw loosening and non-union. Spend 5-10 minutes contouring before applying — this time investment pays dividends in fixation stability.

Distal Clavicle ORIF

Approach

Incision: Direct incision over the distal clavicle and AC joint, 5-6cm. Identify AC joint, expose lateral clavicle superiorly. Identify coracoclavicular ligaments and their integrity to classify fracture type intraoperatively.

Fixation Options

Distal locking plate (anatomic): Preferred by many surgeons. Multiple distal locking screws into the small distal fragment provide angularly stable fixation. May supplement with CC fixation (Endobutton / suture) if proximal fragment control requires it.

Hook plate: Hook engages subacromial space under the acromion. Robust proximal plate shaft with standard screws in clavicle shaft. Excellent initial fixation, useful in very small/comminuted distal fragments. Routine planned removal once united (typically 3-6 months) — retention causes subacromial impingement, acromial osteolysis/erosion, rotator cuff damage, and acromial stress fracture. Counsel and consent the patient for the second procedure at the outset.

Intramedullary / suspensory options: A Knowles pin is a historical intramedullary option. Distinct from this, a coracoclavicular suspensory device (e.g. TightRope/Endobutton) is NOT intramedullary — it reconstructs or augments the CC tether and can be used alone in very small distal fragments or to supplement a plate.

Coracoclavicular fixation supplement: For highly comminuted distal fractures, add CC cerclage (heavy non-absorbable suture or Endobutton around coracoid) to control superior migration of the proximal fragment, regardless of plate construct.

Key Technical Points — Distal ORIF

Confirm fracture classification under direct vision by assessing CC ligament attachments. Reduce fracture with gentle traction and depression of the proximal fragment. Apply plate with distal locking screws angled to purchase multiple cortices in the small distal fragment. If hook plate used, ensure hook is appropriately sized for acromial thickness and seated under the posterior acromion to avoid anterior hook migration.

Postoperative Management

Immobilisation

Midshaft ORIF (stable plate fixation): Simple arm sling for comfort, 2-4 weeks. No formal splint required with rigid plate constructs. Immediate pendulum exercises.

Distal ORIF: Arm sling 4-6 weeks, longer if fixation less rigid (hook plate adequately rigid — 4 weeks). No shoulder ER mobilisation until 4 weeks.

Hook plate patients: Remind patient and all treating clinicians at every encounter: hook plate MUST be removed at 3-6 months.

Rehabilitation Phases

Phase 1 (weeks 0-6): Sling, pendulum exercises from day 1, gravity-assisted ROM. No active abduction against gravity until radiographic callus confirmed (typically week 6-8). Physiotherapy for cervical spine and distal joints.

Phase 2 (weeks 6-12): Active-assisted then full active ROM. Strengthen rotator cuff and periscapular stabilisers. No contact sport, no overhead lifting greater than 5kg.

Phase 3 (weeks 12-16+): Progressive strengthening, sport-specific loading. Return to light manual work at 8-12 weeks, heavy manual work and contact sport at 12-16 weeks (imaging-confirmed union required).

Radiographic Follow-up

AP and 15-degree cephalad-tilt views at 6 weeks and 12 weeks. Union = bridging callus on minimum 3 of 4 cortices on two views. Persistent lucency at 12 weeks — investigate for non-union.

Driving

Patients can typically return to driving an automatic vehicle at 4-6 weeks (when sling removed and adequate shoulder control), and manual vehicle at 6-8 weeks. Advise to verify with insurer.

Work Return Guidelines

Sedentary work (office, computer, administrative): typically 2-4 weeks post-ORIF when sling is comfortable.

Light manual work (shop floor, light assembly, retail): 8-10 weeks, when shoulder strength adequate and union progressing on imaging.

Heavy manual work / contact sport: 12-16 weeks minimum, confirmed radiographic union on two views required. Occupation-specific functional testing should guide exact return — don't rely on calendar date alone.

Plate Removal Counselling — Midshaft

Not all plates require removal. For asymptomatic hardware with confirmed union, plate retention is safe indefinitely. Reasons for removal:

• Symptomatic plate prominence with local skin irritation (most common reason — 9-15% of superior plates)
• Patient request for cosmetic reasons
• Infection not resolving with hardware in situ (rare if fracture united)
• Young patient planning contact sport for many years (reduce stress fracture risk at plate edge)

Plate removal is typically planned at 12-18 months post-surgery after confirmed union. Inform patients at initial consent that removal is possible (not guaranteed) and that it is an additional planned surgical procedure with its own small risk profile.

Monitoring for Non-Union

Warn patients that failure of union is still possible (less than 1% with ORIF) and to return if pain persists beyond 12 weeks without improvement. Risk factors for non-union to reinforce postoperatively: smoking cessation (critical — provide smoking cessation support), avoid NSAID overuse, ensure adequate protein and calcium intake, optimise any underlying metabolic conditions.