Upper Limbs

Hand Tendon Injuries

Tendon Injuries and Overuse Syndromes: Pathophysiology, Causes, Tests, Signs, Osteopathic Management, Zone Classifications, and Figure Examples

1. Extensor Tendon Injuries

Extensor tendon injuries are classified into zones I to VIII, depending on the injury location. These injuries affect the tendons responsible for extending the fingers and wrists, and the severity depends on the zone and the extent of the damage.

Zone Classifications and Examples:

• Zone I: Terminal extensor tendon at or distal to the DIP joint. Example: Mallet finger (see Fig. 1 , extensor tendon zones).

• Zone II: Injury over the middle phalanx of a digit or proximal phalanx of the thumb.

• Zone III: Central slip at the PIP joint, leading to Boutonnière deformity (see Fig. 2  for pathomechanics).

• Zone IV: Proximal phalanx of the digit or metacarpal of the thumb.

• Zone V: Metacarpophalangeal (MCP) joint.

• Zone VI: Metacarpal region (most frequently injured zone).

• Zone VII: Wrist joint, often involving disruption of the extensor retinaculum.

• Zone VIII: Musculotendinous junction at the distal forearm.

Pathophysiology:
Extensor tendon injuries involve damage or rupture of tendons, leading to functional deficits like the inability to extend fingers or wrists. Zone-specific injuries can result in deformities such as mallet finger (Zone I) or Boutonnière deformity (Zone III).

Causes:

• Trauma, such as cuts or crush injuries.

• Sudden forced flexion or extension during physical activities like sports.

Signs and Symptoms:

• Zone I (Mallet Finger): Inability to extend the DIP joint; the finger remains in a flexed posture.

• Zone III (Boutonnière Deformity): PIP joint flexion with DIP hyperextension.

• Swelling, tenderness, and loss of movement in the affected area.

Tests and Examinations:

• Elson Test for central slip integrity in Zone III injuries (Boutonnière deformity).

• X-rays to identify bony avulsions in Zone I mallet injuries.

Osteopathic Management:

• Zone I (Mallet Finger): DIP joint extension splinting for 6 weeks, followed by 4-6 weeks of part-time splinting. Avoid hyperextension, as this may cause skin necrosis.

• Zone III (Boutonnière Deformity): Full-time PIP extension splinting for 6 weeks; surgery or dynamic splinting in chronic cases.

• Zone VI: Early protected motion with dynamic splinting to improve prognosis (Fig. 1 for extensor tendon zones and treatment zones).

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2. Flexor Tendon Injuries

Flexor tendon injuries are classified into zones I to V, depending on the site of injury. Flexor tendons allow finger flexion, and injuries often result in a loss of flexion in affected digits.

Zone Classifications and Examples:

• Zone I: FDP tendon avulsion distal to the FDS insertion (see rugger jersey finger in Fig. 4 for flexor tendon zones).

• Zone II: Between the FDS insertion and the distal palmar crease—often referred to as "no man's land" due to the complexity of repairs.

• Zone III: From the distal palmar crease to the carpal tunnel.

• Zone IV: Injury within the carpal tunnel.

• Zone V: Between the proximal carpal tunnel and the musculotendinous junction.

Pathophysiology:
Flexor tendons are damaged, leading to deficits in finger flexion. In Zone I, injuries (e.g., jersey finger) involve the avulsion of the flexor digitorum profundus (FDP) tendon. Zone II injuries, known as "no man’s land," are complex and involve both FDP and FDS tendons.

Causes:

• Traumatic injuries during sports or accidents, especially involving forced extension during active flexion (e.g., pulling on a jersey causing flexor tendon rupture).

Signs and Symptoms:

• Zone I (Jersey Finger): Inability to flex the DIP joint.

• Zone II: Loss of active flexion at both the PIP and DIP joints.

• Swelling, tenderness along the flexor tendon sheath.

Tests:

• Check isolated DIP (FDP function) and PIP (FDS function) to diagnose the location of injury.

Osteopathic Management:

• Zone I (Jersey Finger): Surgical repair for FDP avulsions, with early protected motion during rehabilitation (see Fig 4.  for profundus tendon avulsions classification).

• Zone II: Direct repair of both FDP and FDS with early mobilization protocols to reduce adhesion formation. Postoperative protocols focus on tendon gliding exercises to restore movement.

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3. Mallet Finger (Zone I Extensor Tendon Injury)

Zone Classification:

• Zone I: Terminal extensor tendon at the DIP joint (see mallet finger illustration in Fig. 1 ).

Pathophysiology:
Sudden forced flexion of the extended fingertip results in rupture of the terminal extensor tendon, leaving the patient unable to actively extend the DIP joint.

Causes:

• Sudden trauma, typically during sports, causing forced flexion of the DIP joint.

Signs and Symptoms:

• The finger remains in a flexed position at the DIP joint.

• In cases of bony mallet, a bony avulsion can occur at the dorsal base of the distal phalanx.

Osteopathic Management:

• Nonoperative: DIP extension splinting for 6 weeks, followed by part-time splinting.

• Operative: Surgery in cases of displaced bony mallet injuries or chronic deformity (refer to bony mallet treatment in Fig. 1 ).

4. Boutonnière Deformity (Zone III Extensor Tendon Injury)

Zone Classification:

• Zone III: Central slip at the PIP joint (see Boutonnière deformity pathomechanics in Fig. 2 ).

Pathophysiology:
A rupture of the central slip results in unopposed flexion at the PIP joint, with compensatory DIP hyperextension due to volar subluxation of the lateral bands.

Causes:

• Direct trauma to the central slip of the extensor tendon, commonly due to cuts or sports injuries.

Signs and Symptoms:

• PIP joint flexion with DIP hyperextension (Boutonnière deformity).

• Loss of active PIP extension.

Osteopathic Management:

• Acute: Full-time PIP extension splinting for 6 weeks.

• Chronic: May require dynamic splinting or reconstructive surgery (see Fig. 2  for pathomechanics of Boutonnière deformity).

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5. De Quervain’s Tenosynovitis

Zone Classification:

• Involves the first extensor compartment of the wrist, affecting the APL and EPB tendons.

Pathophysiology:
Inflammation and thickening of the tendon sheath around the APL and EPB tendons, causing pain and restricted thumb movement.

Causes:

• Repetitive thumb and wrist movements, common in new mothers, golfers, and racket sport players.

Signs and Symptoms:

• Pain at the radial side of the wrist.

• Positive Finkelstein test: Pain is elicited by ulnar deviation of the wrist while holding the thumb inside the fist.

Osteopathic Management:

• Rest, splinting, NSAIDs, and corticosteroid injections.

• Surgical release of the first extensor compartment in refractory cases.

6. Trigger Finger (Stenosing Tenosynovitis)

Zone Classification:

• Involves the flexor tendons at the A1 pulley near the metacarpophalangeal (MCP) joint.

Pathophysiology:
The flexor tendon sheath becomes narrowed, causing inflammation and difficulty gliding, resulting in finger locking during flexion and extension.

Causes:

• Repetitive gripping or activities involving flexion of the fingers.

Signs and Symptoms:

• Locking or catching sensation in the fingers, especially upon extension.

• Pain and tenderness at the base of the finger (A1 pulley).

Osteopathic Management:

• Corticosteroid injections.

• Surgical release of the A1 pulley for cases unresponsive to conservative management.

Comparison with Other Tendinopathies:

• De Quervain’s Tenosynovitis vs. Trigger Finger: De Quervain’s affects the wrist (APL and EPB tendons), while trigger finger affects the flexor tendons at the A1 pulley.

• Zone I Extensor Tendon Injuries (Mallet Finger) vs. Zone III Extensor Tendon Injuries (Boutonnière): Mallet finger involves the DIP joint, while boutonnière deformity affects the PIP joint.

• Flexor Tendon Injuries in Zone II are more complex due to the involvement of both FDP and FDS, making them harder to treat compared to extensor tendon injuries

These injuries, illustrated by specific zones and corresponding figures (e.g., Fig. 1 , 2 , 3, 4 ), require careful diagnosis and osteopathic management based on the extent of the injury

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Distal Radioulnar Joint (DRUJ), Triangular Fibrocartilage Complex (TFCC), and Wrist Conditions: Pathophysiology, Causes, Signs, Symptoms, and Osteopathic Management

 

1. Overview and Pathophysiology:

The Distal Radioulnar Joint (DRUJ) and the Triangular Fibrocartilage Complex (TFCC) are essential components in wrist function, enabling forearm rotation and wrist stability. Injuries or degenerative conditions affecting these structures can result in significant pain, loss of motion, and reduced function. Osteopathy and physical therapy play vital roles in restoring wrist stability, improving mobility, and reducing pain through a combination of manual therapy, mobilization techniques, and rehabilitation exercises.

2. Conditions of the DRUJ and TFCC

Here’s an overview of the DRUJ and TFCC, including their anatomy, associated conditions, causes, signs, symptoms, diagnostic tests, physical examination findings, and management through osteopathy and physical therapy.

A. DRUJ Instability

• Anatomy:

  • The radius rotates around a fixed ulna at the DRUJ, with soft tissues contributing 80% to its stability, while the distal radius provides 20%.

  • The Triangular Fibrocartilage Complex (TFCC), ulnocarpal ligaments, and extensor carpi ulnaris (ECU) tendon are essential stabilizing structures​.

• Causes:

  • Acute trauma such as a fall on an outstretched hand.

  • Chronic instability due to repetitive stress or ligamentous injury (e.g., from overuse in sports).

  • Distal radius fractures that heal with malalignment can cause chronic instability.

• Signs and Symptoms:

  • Pain on the ulnar side of the wrist, especially with pronation and supination.

  • Weakness and a feeling of instability in the wrist.

  • Reduced grip strength.

• Test and Physical Examination:

  • Piano Key Sign: Pain or excessive mobility when the distal ulna is pressed dorsally.

  • Ballottement Test: Laxity or pain when manipulating the ulna and radius.

  • Sequential CT Scans: Assesses translation of the ulna relative to the radius, with more than 50% translation considered abnormal​​.

• Osteopathy and Physical Therapy Management:

  • Manual Therapy: Osteopathic manipulation focuses on restoring alignment, reducing tension in the ECU tendon, and enhancing mobility through soft tissue release and joint mobilization​.

  • Physical Therapy: Strengthening exercises for the wrist and forearm to improve stability. Proprioception exercises like wobble board use can retrain the stabilizing muscles. Bracing may be used for additional support during the healing process.

  • Surgical Options: If instability persists, surgical options include TFCC repair, ligament reconstruction, or corrective osteotomy in cases of distal radius malunion.

B. TFCC Tears

• Anatomy:

  • The TFCC consists of the articular disc, meniscus homologue, radioulnar ligaments, and ulnolunate and ulnotriquetral ligaments. It stabilizes the DRUJ and transmits about 20% of the axial load across the wrist​.

• Causes:

  • Traumatic Injuries (Class 1): Often occur from a fall on an outstretched hand or a sudden twist of the wrist.

  • Degenerative Tears (Class 2): Occur gradually due to repetitive wrist motion or overloading, especially in individuals with positive ulnar variance (where the ulna is longer than the radius).

• Signs and Symptoms:

  • Ulnar-sided wrist pain, especially with forearm rotation or gripping.

  • Clicking or snapping sensations with wrist movement.

  • Weakness and reduced grip strength.

• Test and Physical Examination:

  • TFCC Compression Test: Ulnar wrist pain with loading the wrist in ulnar deviation and extension.

  • MRI: Can show TFCC pathology, though arthroscopy remains the gold standard for diagnosis​​.

  • Arthroscopic Tests:

    • Trampoline Test: Balloting the TFCC with a small probe to assess resiliency.

    • Hook Test: Assesses for peripheral detachment of the TFCC.

• Osteopathy and Physical Therapy Management:

  • Nonoperative Treatment: Immobilization of the wrist with a splint and NSAIDs for pain management.

  • Osteopathic Treatment: Gentle mobilization techniques to reduce strain on the TFCC and restore balance in wrist mechanics. Focused work on the ulnar side of the wrist can help improve flexibility and reduce tension​.

  • Physical Therapy: Strengthening exercises for the wrist and forearm, particularly focusing on grip and rotation strength. Progressive ROM exercises to restore movement without stressing the TFCC.

  • Surgical Treatment: For severe cases, wrist arthroscopy may be required for debridement or repair, especially in traumatic tears (Class 1B)​.

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Elbow , Shoulder Coming soon......