4.2 Ankle, Elbow & Wrist Arthroplasty: Indications, Nursing Management & Functional Outcomes

Total Ankle Arthroplasty (TAA): Indications, Wound Biology, and Management

End-stage ankle osteoarthritis (OA) differs etiologically from hip and knee arthritis; more than 70% to 80% of cases are post-traumatic (following malleolar fractures, pilon fractures, or recurrent chronic ligamentous instability), with the remainder resulting from rheumatoid arthritis or primary degenerative disease. The two definitive surgical options for end-stage disease are Total Ankle Arthroplasty (TAA) and Ankle Arthrodesis (Tibiotalar Fusion).

                 ANKLE ARTHROPLASTY VS. ARTHRODESIS DECISION

         [Total Ankle Arthroplasty (TAA)]         [Ankle Arthrodesis (Fusion)]
                        |                                       |
       - Preserves 20°-30° sagittal arc        - Rigid, stable, durable joint
       - Protects subtalar & midtarsal         - Accelerates adjacent joint OA
         joints from adjacent-segment OA         (subtalar / talonavicular)
       - Low-to-moderate demand patients       - High-demand laborers, young patients
       - Requires <15° coronal deformity       - Tolerates severe deformities (>20°)
       - Contraindicated in Charcot & PAD      - Gold standard for Charcot arthropathy

Clinical Decision-Making: TAA vs. Arthrodesis

• Ankle Arthrodesis: Historically the gold standard. It provides a rigid, pain-free, plantigrade foot capable of withstanding heavy occupational and manual loads. However, eliminating tibiotalar motion transfers compensatory mechanical stresses to the adjacent subtalar and transverse tarsal (talonavicular/calcaneocuboid) joints, leading to symptomatic adjacent-segment osteoarthritis in over 50% of patients within 10 years.
• Total Ankle Arthroplasty: Replaces the distal tibia and talus with metallic tibial/talar components separated by a mobile or fixed ultra-high-molecular-weight polyethylene (UHMWPE) bearing. TAA preserves a physiological sagittal arc of 20° to 30° (dorsiflexion and plantarflexion), normalizing gait kinematics, reducing energy expenditure, and shielding adjacent hindfoot joints from premature degeneration.
• Ideal TAA Candidates: Low-to-moderate physical demand, age >50 years, normal body mass index, preserved bone stock, and minimal or correctable coronal plane deformity (<15° varus or valgus).
• Absolute & Relative Contraindications to TAA:
  1. Charcot Neuroarthropathy: Severe peripheral neuropathy / loss of protective sensation results in rapid mechanical failure and catastrophic component collapse.
  2. Active or Recent Septic Arthritis: Absolute contraindication.
  3. Severe Fixed Coronal Malalignment (>15°–20°): Unbalanced shear forces cause early edge-loading and poly wear.
  4. Avascular Necrosis (AVN) of the Talus (>33%–50%): Inadequate structural support for the talar component.
  5. Severe Peripheral Arterial Disease (PAD): Precludes adequate anterior wound healing.

Surgical Corridor and Anterior Wound Biology

TAA is performed through an anterior longitudinal midline approach between the tibialis anterior (TA) tendon medially and the extensor hallucis longus (EHL) tendon laterally.

• Neurovascular Vulnerabilities: The deep peroneal nerve and dorsalis pedis artery travel beneath the EHL and extensor digitorum longus (EDL) and must be carefully retracted laterally with the vascular bundle. The medial and lateral dorsal cutaneous branches of the superficial peroneal nerve run in the subcutaneous fat and are vulnerable to traction injury, causing numbness over the dorsum of the foot.
• The Fragile Anterior Angiosome: The anterior ankle skin is thin, with minimal subcutaneous padding, tenuous microvascular perfusion, and zero muscle coverage overlying the tibia. Wound dehiscence, marginal skin necrosis, and secondary tendon/implant exposure represent limb-threatening emergencies.

Postoperative TAA Nursing Care Protocol

1. Strict Limb Elevation ("Toes Above the Nose"): For the first 48 to 72 hours, the operative extremity must remain continuously elevated above the level of the right atrium. Dependent positioning is restricted to brief bathroom transfers only, as severe edema compromises anterior incision perfusion.
2. Non-Weight-Bearing (NWB) Immobilization: The patient is placed in a well-padded posterior splint or non-weight-bearing bivalved cast for 2 to 6 weeks to permit primary skin healing and biological osseointegration of porous-coated components. Weight-bearing is strictly prohibited.
3. Progressive Rehabilitation: Transition to protected weight-bearing in a controlled ankle motion (CAM) boot occurs after wound maturation (typically weeks 3 to 6), accompanied by gentle active dorsiflexion and plantarflexion exercises (inversion/eversion are restricted initially).

Total Elbow Arthroplasty (TEA): Designs, Ulnar Transposition & Lifetime Restrictions

Total Elbow Arthroplasty (TEA) is a specialized procedure that restores upper extremity function, relieves severe joint pain, and re-establishes an arc of flexion-extension necessary for feeding, grooming, and personal hygiene. Unlike weight-bearing lower extremity implants, the elbow experiences complex distracting and multiplanar torsional stresses during daily activity.

Indications and Prosthetic Classifications

• Clinical Indications: Severe end-stage rheumatoid arthritis (destructive Larsen grade IV/V arthritis), comminuted intra-articular distal humerus fractures in elderly patients (OTA/AO 13-C3 fractures not amenable to stable internal fixation), post-traumatic osteoarthrosis, and gross elbow instability.
• Linked (Semi-Constrained / "Sloppy-Hinge") Implants: The humeral and ulnar stems are mechanically connected with an internal linking axle pin and ultra-high-molecular-weight polyethylene bushings (e.g., Coonrad-Morrey prosthesis). The hinge design incorporates 7 to 10 degrees of varus-valgus and rotational "play" (laxity). This controlled toggle dampens the transfer of severe torsional loads to the bone-cement interface, drastically reducing aseptic loosening. Linked implants are the standard of care for rheumatoid arthritis and acute trauma.
• Unlinked (Resurfacing) Implants: Humeral and ulnar components have no mechanical connection, relying entirely on intact medial and lateral collateral ligaments and balanced muscular dynamic stabilizers. They carry a high rate of dislocation and instability if soft tissues are compromised.

                      TOTAL ELBOW ARTHROPLASTY PROTOCOLS

    [Surgical Management]                    [Strict Lifetime Precautions]
    - Posterior midline incision             - LIFETIME weight-bearing limit:
    - Routine anterior ulnar nerve             * 5 to 10 lbs (2.3-4.5 kg) single lift
      transposition to prevent neuropathy      * 1 to 2 lbs (0.5-1.0 kg) repetitive
    - Triceps-reflecting / sparing exposure  - NO pushing up from chairs/beds
    - Semi-constrained sloppy-hinge design   - NO high-impact or vibratory tools

Ulnar Nerve Management and Triceps Precautions

• Ulnar Nerve Neurolysis and Anterior Transposition: The ulnar nerve passes directly posterior to the medial epicondyle through the cubital tunnel. During TEA, the ulnar nerve is routinely dissected free and transposed anteriorly into the subcutaneous or submuscular tissue. This prevents nerve stretch, compression, or entrapment during postoperative elbow flexion.
• Postoperative Ulnar Nerve Surveillance: Orthopaedic nurses must assess:
  1. Sensory: Light touch and two-point discrimination over the volar and dorsal aspects of the 5th digit (little finger) and medial half of the 4th digit (ring finger).
  2. Motor: First dorsal interosseous muscle strength (index finger abduction against resistance) and hypothenar strength (abductor digiti minimi).
• Triceps Mechanism Protection: In triceps-reflecting or triceps-splitting exposures, the triceps extensor tendon is repaired back to the olecranon with heavy transosseous sutures. Active triceps extension against gravity or resistance is strictly prohibited for 6 weeks to prevent extensor tendon avulsion.

Mandatory Lifetime Lifting Restrictions

Because of the delicate mechanics of the elbow and high polyethylene bushing wear rates under load, TEA patients must be educated on non-negotiable permanent lifetime load limits:

• Maximum Single Lift: Strictly 5 to 10 pounds (2.3 to 4.5 kg) (equivalent to a gallon of milk).
• Maximum Repetitive Lift: Strictly 1 to 2 pounds (0.5 to 1.0 kg) (e.g., a coffee cup or book).
• No Upper-Body Weight Bearing: Patients must never push themselves up out of a chair or bed using the operative arm.
• Violating these restrictions results in rapid poly bushing wear, metallosis, hinge disengagement, and catastrophic aseptic stem loosening.

Total Wrist Arthroplasty (TWA): Motion Preservation vs. Arthrodesis

Total Wrist Arthroplasty (TWA) is an established reconstructive option designed to preserve a functional arc of radiocarpal motion in patients with severe, pancarpal destruction.

Clinical Comparison: TWA vs. Total Wrist Arthrodesis

• Total Wrist Arthrodesis (Fusion): Remains the primary standard for high-demand patients, young manual laborers, and post-traumatic pancarpal arthritis. Fusion provides complete pain relief, excellent grip strength, and lifelong durability without failure risk, though it permanently eliminates all radiocarpal and midcarpal flexion, extension, and radial/ulnar deviation (pronation and supination are preserved at the radioulnar joints).
• Total Wrist Arthroplasty: Utilizes a metallic radial component, a central carpal plate anchored into the capitate and metacarpal bases, and an ultra-high-molecular-weight polyethylene articulating insert.
• Primary Indications for TWA: Low-demand patients with bilateral rheumatoid arthritis (RA) or severe inflammatory joint destruction. In patients with bilateral disease, having at least one mobile wrist (preserving a 30° extension / 30° flexion functional arc) is critical for independent personal hygiene, perineal care, fastening buttons, and eating.
• Postoperative Nursing Management: Splint immobilization in 10°–15° of wrist extension for 2 to 4 weeks, followed by protected range-of-motion therapy. Patients must observe a permanent lifetime lifting restriction of 5 to 10 pounds and avoid all contact sports or heavy manual gripping.