A SLAC wrist, or Scapholunate Advanced Collapse, is a specific pattern of degenerative arthritis in the wrist resulting from long-standing instability and deformity, primarily affecting the radiocarpal and midcarpal joints.
Understanding SLAC Wrist
SLAC wrist develops as a consequence of untreated or inadequately treated scapholunate ligament injuries. This ligament connects the scaphoid and lunate bones in the wrist. When this ligament is torn or weakened, it leads to abnormal movement between these bones. This instability progresses over time, eventually causing arthritis.
Progression of SLAC Wrist
The progression of SLAC wrist typically follows a predictable pattern:
- Scapholunate Ligament Injury: Initially, the scapholunate ligament is damaged, leading to instability between the scaphoid and lunate.
- Abnormal Biomechanics: The abnormal movement causes uneven pressure distribution within the wrist joint.
- Cartilage Damage: Over time, the cartilage covering the bones begins to wear away due to the increased pressure and friction.
- Arthritis Development: As cartilage deteriorates, bone rubs against bone, leading to pain, stiffness, and the development of arthritis.
- Joint Collapse: In advanced stages, the wrist joint can collapse, leading to significant deformity and loss of function.
Symptoms of SLAC Wrist
Common symptoms of SLAC wrist include:
- Wrist pain, especially with activity.
- Clicking, popping, or grinding sensations in the wrist.
- Stiffness and limited range of motion.
- Weakness in the wrist and hand.
- Swelling and tenderness around the wrist joint.
Diagnosis and Treatment
Diagnosis typically involves a physical examination, X-rays, and potentially other imaging studies like MRI. Treatment options range from conservative measures like splinting and pain medication to surgical interventions aimed at stabilizing the wrist or relieving pain. Surgical options may include ligament reconstruction, limited wrist fusion, or complete wrist fusion.
