Clinical Description: Chronic (Neglected) Posterior Elbow Dislocation

What the Image Shows

• Gross posterior prominence — the olecranon and proximal ulna are visibly displaced posteriorly relative to the distal humerus, creating a characteristic "step-deformity" at the posterior elbow
• Fixed flexion deformity — the elbow is held in approximately 30–45° of flexion and cannot be fully extended; in chronic cases this becomes rigid due to fibrous ankylosis and contracture
• Soft tissue swelling and skin changes — diffuse circumferential swelling with stretched, thinned overlying skin typical of long-standing tissue edema and fibrosis
• Bandaging over the forearm/wrist — suggestive of associated injury or post-surgical dressing
• Limb resting in a semi-pronated position — consistent with the typical posture of a neglected posterior dislocation

Clinical Classification

• Fibrous tissue fills the olecranon fossa
• Collateral ligaments and capsule contract and scar
• Periarticular heterotopic ossification may begin
• Closed reduction becomes impossible

Pathoanatomy of Chronic Dislocation

1. Ligamentous disruption — Both medial collateral ligament (MCL) and lateral collateral ligament (LCL) are torn and contracted in the dislocated position
2. Capsular contracture — The anterior and posterior capsule shortens, locking the joint
3. Muscle contracture — Brachialis, triceps, and forearm flexor/extensor origins contract over the displaced bony architecture
4. Periarticular fibrosis and potential heterotopic ossification — Organized fibrous tissue bridges the joint space
5. Articular cartilage degeneration — Progressive if reduction is delayed beyond weeks to months
6. Neurovascular risk — Ulnar nerve is at particular risk from stretching and scarring; brachial artery may be tethered

Formal Clinical Description (for case notes / presentation)

"The right elbow demonstrates a chronic posterior dislocation with a prominent posterior olecranon, fixed flexion deformity at approximately 30–45°, and diffuse periarticular soft tissue swelling. The limb is in the operating theatre position. There is no open wound visible. The deformity is consistent with a neglected posterior ulnohumeral dislocation with expected periarticular fibrosis and contracture, requiring operative open reduction."

Management Principles for Chronic Elbow Dislocation

1. Open reduction — via posterior or combined medial-lateral approaches; fibrous tissue in the olecranon fossa must be excised
2. Ligamentous reconstruction — MCL ± LCL repair or augmentation
3. Capsular release — anterior and posterior
4. Possible hinged external fixation — to maintain reduction while allowing early mobilization
5. Internal joint stabilizer — an emerging technique for post-reduction instability (Salazar et al., JSES 2022, PMID 37587970)
6. Interposition arthroplasty — reserved for cases with significant articular destruction (Tafoya-Arreguín et al., JAAOS 2022, PMID 35551161)

Triceps in Chronic Elbow Dislocation

What Happens to the Triceps

• The triceps is dragged posteriorly with the olecranon as the forearm subluxes/dislocates
• Over weeks, the triceps shortens and contracts in the new posterior position
• It becomes a deforming force — actively preventing reduction by pulling the olecranon further posterior
• Periarticular scarring incorporates the triceps, making it adherent to surrounding structures

Why the Triceps Matters Surgically

Old Approach (Historical)

• Surgeons used a posterior approach with triceps lengthening (Z-plasty or tongue-flap lengthening of the triceps tendon) to gain access to the joint and release the contracture
• This allowed exposure but sacrificed extensor mechanism integrity

Modern Approach (Current Evidence)

"Historically, surgeons recommended a posterior approach with a lengthening of the triceps; however, more recent experience suggests the triceps should be preserved — both to improve motion and to provide stability postoperatively."

What You See in the Image

1. The displaced olecranon (the bony prominence)
2. The contracted triceps muscle belly draped over it — giving the posterior soft tissue its rounded, tense appearance

Summary for Case Documentation

"In this chronic posterior elbow dislocation, the triceps is not ruptured but is contracted and adherent in the posteriorly displaced position. The posterior prominence visible clinically represents the olecranon with the overlying contracted triceps. Operative planning must account for triceps contracture; modern technique favors a combined medial-lateral approach preserving the triceps rather than lengthening it, to maintain post-reduction extensor function and dynamic posterior stability."