The Swanson flexible hinge implant used in metacarpophalangeal joint reconstruction for rheumatoid arthritis is made of silicone rubber. Its most characteristic long-term complication is:
- A Implant fracture and silicone particulate synovitis with peri-implant bone erosion ✓
- B Deep periprosthetic infection requiring implant removal in the majority of cases
- C Progressive ankylosis of the joint due to heterotopic ossification
- D Metallosis from abrasion against the metacarpal head
Correct answer: A. Implant fracture and silicone particulate synovitis with peri-implant bone erosion
Explanation
The Swanson implant acts as a flexible spacer around which a fibrous capsule forms, rather than as a true hinge. With time it may fatigue and fracture, shedding silicone particles that provoke a foreign-body histiocytic response, silicone synovitis, with lytic peri-implant lesions and cyst formation. Infection rates are low, the implant contains no metal, and heterotopic ossification is not a recognised feature at the MCP level.
Reference: Campbell's Operative Orthopaedics, 14th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.