Lateral Ulnar Collateral Ligament (LUCL) Injury
Overview
What it is – A sprain, tear or chronic attenuation of the LUCL, the key posterolateral stabiliser of the elbow.
Why it matters – Loss of LUCL integrity ➜ posterolateral-rotatory instability (PLRI), the commonest form of chronic elbow instability, producing pain, clicking, and functional insecurity.
Anatomy at-a-Glance
Structure | Origin | Insertion | Role |
LUCL | Lateral epicondyle (humerus) | Supinator-crest tubercle (ulna) | Blocks varus & external-rotation forces |
Radial Collateral Lig. (RCL) | Lat. epicondyle | Annular lig. | Resists varus |
Annular Ligament | Ant./post. radial-notch margins | Encircles radial head | Holds radial head to ulna |
Accessory Collateral Lig. | Annular lig. → ulna | Stabilises annular lig. |
Dynamic stabilisers: wrist/finger extensors, anconeus.
Mechanisms of Injury
- Traumatic: fall on out-stretched hand (FOOSH) with axial load + supination + valgus & extension ➜ sequential LCL complex failure.
- Iatrogenic: over-aggressive lateral epicondylitis surgery or elbow arthroscopy.
- Chronic attenuation: cubitus varus malunion creating repetitive varus thrust.
Clinical Presentation
- Lateral elbow pain.
- Mechanical clicking / catching / giving-way especially on pushing up from a chair with forearm supinated.
- Tender LUCL origin or ulnar insertion.
Provocative tests
- Lateral pivot-shift (gold standard)
- Chair-rise / Table-top / Floor push-up tests
- Posterior drawer, Apprehension test
Positive findings: apprehension or frank subluxation 30-45° flexion that reduces ≥ 60-70°.

Diagnostic Imaging
- X-ray: rule-out fracture, look for posterolateral capitellar “Hill-Sachs” defect or calcification.
- MRI / MR-arthrogram: maps LUCL tears, scar tissue, chondral lesions.
- Fluoroscopic pivot-shift: dynamic confirmation of radial-head subluxation.
Management Pathway
- Non-operative (select cases)
Indications | Key elements |
Mild chronic PLRI • Acute simple dislocation now stable • Low-demand patient | • 5–7 days immobilise at 90° (forearm pronated) |
Outcome: Often insufficient for symptomatic PLRI → surgical referral.

- Operative
Option | When? | Technique snapshot |
LUCL repair | Acute tear with good tissue | Anchors / sutures at humeral origin ± internal brace |
LUCL reconstruction(gold standard for chronic) | Chronic PLRI • Failed repair • Poor tissue | Docking or modified docking most common. |
Post-Op Rehabilitation Milestones
Week | Focus | Key points |
0-3 | Protection | Posterior splint → hinged brace; hand, wrist, shoulder AROM |
3-6 | Mobility | Full supination/pronation in ≥ 90° flex; gradual extension (∼30°/wk) with forearm pronated |
6-12 | Strength | Full ROM, isotonic triceps/forearm, scapular stabilisers |
3-6 m | Plyometrics | Sport-specific drills, proprioception |
9-14 m | Return-to-play | Pass functional & psych readiness tests |
Always avoid varus stress & shoulder abduction early.
Outcomes & Complications
- Good-to-excellent results in ~85 % primary reconstructions.
- 93 % achieve functional ROM (30-130°).
- Re-instability: 12 % primary, ↑40 % revision.
- Others: infection, cutaneous nerve irritation, stiffness, rare distal-humerus fracture.
Predictors of poorer outcome: multiple prior surgeries, articular degeneration, revision setting.


Prevention Checklist (Athletes & Coaches)
- Balanced strength & conditioning (core → shoulder → elbow).
- Biomechanics coaching – correct arm slot, trunk control, stride.
- Work-load monitoring – pitch counts, rest days, avoid year-round single-sport.
- Structured warm-up / cool-down, mobility & posterior-shoulder stretching.
- Fatigue management – sleep, HRV / grip-strength tracking.
- Rapid access to sports-med evaluation at first sign of lateral pain.
Glossary
- PLRI – Posterolateral-Rotatory Instability.
- Docking technique – graft ends passed into humeral tunnel and tied over bone bridge for tension control.
- Varus stress – inward angulation force that gaps lateral elbow.
- Cubitus varus – “gun-stock” deformity predisposing to LUCL stretch.
- Tommy John surgery – colloquial term for medial UCL reconstruction; rehabilitation timeline analogous.
Call to Action
If you have pain, book an appointment to be reviewed by Prof Imam or another member of our specialist team at The Arm Clinic. Early specialist care helps prevent long-term issues. Visit www.TheArmDoc.co.uk or book your consultation today. Phone: 020 3384 5588 | Email: Info@TheArmDoc.co.uk
Disclaimer
This information is for general educational purposes and should not be used as a substitute for professional medical advice. Consult a healthcare professional for individual guidance on your condition and treatment options.
Prepared for Arm Doc educational content. Clinical decisions require individual assessment and specialist consultation.
