Introduction to Chronic and Unreduced Dislocations

The management of chronic, neglected, or unreduced dislocations represents one of the most technically demanding frontiers in operative orthopaedics. Unlike acute dislocations, where closed reduction is often successful, chronic dislocations are characterized by severe periarticular fibrosis, capsular contracture, cartilage degradation, and neurovascular tethering. The literature—spanning from Speed’s early work on the elbow to modern hinged external fixation techniques—dictates that successful management requires a deep understanding of altered pathoanatomy, extensile surgical exposures, and meticulous soft-tissue balancing.

This masterclass provides a comprehensive, evidence-based framework for the surgical management of chronic dislocations across the major appendicular joints, tailored for the practicing consultant, fellow, and senior orthopedic resident.

The Hip: Neglected Traumatic Dislocations

Unreduced traumatic dislocations of the hip are predominantly seen in developing nations or following polytrauma where the primary injury was overlooked. The chronicity of the dislocation dictates the treatment algorithm, with avascular necrosis (AVN) of the femoral head being the most critical prognostic factor.

Indications and Preoperative Planning

Closed reduction via heavy traction (as described by Gupta and Pai) may be attempted in dislocations less than 3 weeks old. However, for dislocations persisting beyond 21 days, open reduction is universally indicated. Preoperative computed tomography (CT) is mandatory to assess femoral head impaction fractures, acetabular bone loss, and intra-articular loose bodies.

Surgical Warning: Attempting forceful closed reduction in a chronically dislocated hip carries an unacceptably high risk of iatrogenic femoral neck fracture. Always proceed to open reduction if heavy, progressive skeletal traction fails to mobilize the joint.

Surgical Approach: Posterior Dislocation

For chronic posterior dislocations, the Kocher-Langenbeck approach is the gold standard.
1. Positioning: Lateral decubitus position with the affected leg draped free.
2. Incision and Dissection: An extensile incision is made. The fascia lata and gluteus maximus are split in line with their fibers.
3. Sciatic Nerve Identification: The sciatic nerve is invariably encased in dense scar tissue and displaced by the dislocated femoral head. Meticulous neurolysis is the most critical step.
4. Soft Tissue Release: The short external rotators (if intact) are tagged and released. The fibrotic pseudocapsule must be excised completely. The acetabulum is typically filled with fibrofatty tissue (the pulvinar) and remnants of the ligamentum teres, which must be cleared using curettes and rongeurs.
5. Reduction: Gentle traction and internal rotation are applied. A bone hook around the femoral neck can assist in levering the head into the true acetabulum.
6. Salvage Options: In cases of severe femoral head destruction or established AVN in older patients, primary Total Hip Arthroplasty (THA) is indicated.

Postoperative Protocol

• 0-6 Weeks: Skeletal traction or a hip spica cast may be required if instability persists. Touch-down weight-bearing (TDWB).
• 6-12 Weeks: Progressive weight-bearing and active-assisted range of motion (ROM).
• Long-term: Serial radiographs at 3, 6, 12, and 24 months to monitor for AVN and post-traumatic osteoarthritis.

The Shoulder: Chronic Anterior and Posterior Dislocations

Chronic dislocations of the glenohumeral joint are frequently missed injuries, particularly posterior dislocations following seizures or electrocution. The hallmark of these injuries is a significant osseous defect: the Hill-Sachs lesion (anterior dislocation) or the reverse Hill-Sachs lesion (posterior dislocation).

Chronic Locked Posterior Dislocation

When the humeral head is locked posteriorly, the anterior aspect of the humeral head impacts against the posterior glenoid rim, creating an anteromedial impression fracture.

Surgical Approach: The McLaughlin Procedure and Modifications

For defects involving 20% to 40% of the articular surface, the modified McLaughlin procedure (Neer modification) is indicated.
1. Positioning: Beach chair position.
2. Approach: Deltopectoral approach.
3. Subscapularis Management: The subscapularis tendon is identified. Instead of detaching it from the lesser tuberosity, an osteotomy of the lesser tuberosity is performed.
4. Reduction: The joint is gently levered into place. Extensive release of the posterior capsule may be required.
5. Defect Grafting/Transfer: The lesser tuberosity, with the attached subscapularis tendon, is transferred into the reverse Hill-Sachs defect and secured with cancellous screws. This prevents the defect from engaging the glenoid rim during internal rotation.
6. Alternative (Rotational Osteotomy): As described by Keppler et al., a proximal humeral rotational osteotomy can be utilized to rotate the defect out of the functional arc of motion.

Clinical Pearl: If the articular defect exceeds 45-50% of the humeral head, or if the cartilage is severely degenerated, joint preserving procedures will fail. Primary hemiarthroplasty or total shoulder arthroplasty is the definitive treatment.

Chronic Anterior Dislocation

Chronic anterior dislocations require open reduction, often combined with a Latarjet procedure (coracoid transfer) to address concurrent glenoid bone loss and provide a robust anterior sling.

The Elbow: Unreduced Posterior Dislocations

The elbow is highly unforgiving of prolonged immobilization or chronic dislocation. Unreduced posterior dislocations rapidly develop severe periarticular fibrosis, heterotopic ossification, and contracture of the triceps mechanism.

Biomechanics and Indications

The primary block to reduction in a chronic posterior elbow dislocation is the contracted triceps, the fibrotic collateral ligaments, and the obliteration of the olecranon and coronoid fossae by scar tissue. Open reduction is indicated for all chronic dislocations to restore the hinge mechanism and prevent severe functional impairment.

Surgical Approach: Extensile Posterior Release

1. Positioning: Lateral decubitus with the arm draped over a radiolucent post.
2. Incision: A universal posterior midline incision, curving slightly laterally around the olecranon to avoid the ulnar nerve.
3. Ulnar Nerve Transposition: The ulnar nerve must be identified proximally, neurolysed, and transposed anteriorly to prevent traction injury during reduction.
4. Triceps Management: A V-Y tricepsplasty or a triceps-reflecting (Bryan-Morrey) approach is utilized to gain access to the joint. Speed’s original operation emphasizes the necessity of completely mobilizing the triceps.
5. Capsular Release: The fibrotic collateral ligaments and anterior capsule are sharply excised. The olecranon fossa is cleared of all fibrous tissue.
6. Reduction and Stabilization: The joint is reduced. Because the collateral ligaments are often incompetent, the joint is highly unstable post-reduction.
7. Hinged External Fixation: As popularized by Jupiter and Ring, the application of a dynamic hinged external fixator is paramount. The axis pin is placed precisely through the center of rotation of the capitellum and trochlea. This allows for immediate postoperative ROM while maintaining concentric reduction.

Postoperative Protocol

• Days 1-14: Continuous passive motion (CPM) is initiated immediately via the hinged external fixator.
• Weeks 6-8: The external fixator is removed. Aggressive active and active-assisted ROM continues. Night splinting in extension is utilized to combat flexion contractures.

Clavicular Joints: Sternoclavicular and Acromioclavicular Dislocations

Chronic Acromioclavicular (AC) Joint Dislocation

Chronic, symptomatic Type III-V AC joint dislocations require surgical reconstruction. The native coracoclavicular (CC) ligaments are beyond primary repair.

Surgical Technique: Modified Weaver-Dunn and Anatomic Reconstruction

1. Distal Clavicle Excision (Mumford): The distal 1 cm of the clavicle is excised to prevent painful AC joint impingement.
2. Ligament Transfer: The coracoacromial (CA) ligament is detached from the acromion and transferred into the medullary canal of the distal clavicle.
3. Augmentation: Because the CA ligament is biomechanically inferior to the native CC ligaments, modern techniques mandate augmentation with a free tendon graft (e.g., semitendinosus) looped in a figure-of-eight fashion under the coracoid and through drill holes in the clavicle.

Chronic Sternoclavicular (SC) Joint Dislocation

Anterior SC dislocations are generally benign and rarely require surgery. Conversely, posterior (retrosternal) SC dislocations are true orthopedic emergencies due to the proximity of the great vessels, trachea, and esophagus. Chronic posterior dislocations can present with Thoracic Outlet Syndrome (TOS).

Surgical Warning: Never attempt an open reduction of a chronic posterior SC joint dislocation without a cardiothoracic surgeon scrubbed or immediately available on standby. The risk of catastrophic hemorrhage from the brachiocephalic vein or subclavian artery is significant.

Surgical Technique

1. Approach: An anterior incision over the medial clavicle and manubrium.
2. Reduction: A towel clip is used to grasp the medial clavicle and apply anterior traction.
3. Stabilization: If unstable, a figure-of-eight reconstruction using a semitendinosus autograft is performed through drill holes in the manubrium and medial clavicle. Never use K-wires in the SC joint due to the fatal risk of intrathoracic migration.

The Knee and Proximal Tibiofibular Joint

Chronic Knee Dislocation

Delayed presentation of a knee dislocation implies a multi-ligamentous knee injury (MLKI) that has healed in a subluxated or dislocated position.
* Management: Open reduction requires extensive lysis of adhesions. Staged reconstruction of the cruciate and collateral ligaments using allografts is necessary. In older patients with chronic posterior dislocations and secondary osteoarthritis, Total Knee Arthroplasty (TKA) utilizing a rotating-hinge or fully constrained prosthesis is the treatment of choice (as described by Petrie et al.).

Proximal Tibiofibular Joint (PTFJ) Instability

Recurrent or chronic dislocation of the PTFJ (Ogden classification) often presents as lateral knee pain and transient common peroneal nerve palsy.
* Surgical Options:
* Capsular Shift/Reconstruction: Using a slip of the biceps femoris tendon to reconstruct the anterior tibiofibular ligament.
* Arthrodesis: Fusion of the joint, though this alters ankle biomechanics and requires concurrent fibular shaft osteotomy.
* Fibular Head Resection: Excision of the proximal fibula, taking extreme care to protect the common peroneal nerve.

The Distal Radioulnar Joint (DRUJ)

Chronic anterior or posterior dislocations of the ulnar head result in severe restriction of forearm pronation and supination, accompanied by debilitating ulnar-sided wrist pain.

Surgical Management: The Darrach and Sauvé-Kapandji Procedures

When the triangular fibrocartilage complex (TFCC) is irreparably damaged and secondary osteoarthritis has set in, salvage procedures are indicated.
1. The Darrach Procedure: Involves subperiosteal resection of the distal 1-2 cm of the ulnar head. While effective for pain relief in low-demand patients, it can lead to radioulnar impingement.
2. The Sauvé-Kapandji Procedure: Preferred in younger, higher-demand patients. The articular surface of the ulnar head is fused to the sigmoid notch of the radius, and a pseudoarthrosis is created proximal to the fusion by excising a 1.5 cm segment of the ulnar shaft. This preserves the ulnocarpal ligaments while restoring forearm rotation.

The Foot: Chronic Dislocation of the Lesser Toes

Chronic dislocations of the metatarsophalangeal (MTP) joints, particularly the fifth toe as described by Jahss, often result from neglected trauma or severe inflammatory arthropathy.

Surgical Approach

1. Soft Tissue Release: A dorsal longitudinal incision is made. Extensor tendon lengthening (Z-plasty) and dorsal capsulotomy are performed.
2. Osseous Resection: If soft tissue release is insufficient, a Weil osteotomy (distal metatarsal shortening osteotomy) is executed to decompress the joint and allow concentric reduction.
3. Fixation: The joint is stabilized with a transarticular K-wire for 4 weeks.

Conclusion

The operative management of chronic and unreduced dislocations demands a high level of surgical acumen. The overarching principles remain consistent across all anatomical regions: meticulous preoperative imaging, extensile surgical approaches, identification and protection of neurovascular structures, complete excision of fibrotic barriers, and robust stabilization—often requiring osteotomies, tendon transfers, or hinged external fixation. Adherence to these evidence-based protocols ensures the highest probability of restoring joint congruity, alleviating pain, and maximizing functional recovery in these complex clinical scenarios.

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