Murray Peter M
Department of Orthopedic Surgery, Division of Hand and Microsurgery, The Mayo Clinic, Jacksonville, FL, USA.
J Am Acad Orthop Surg. 2003 Sep-Oct;11(5):295-301. doi: 10.5435/00124635-200309000-00002.
Prosthetic replacement in the hand must address such unique challenges as preservation of the collateral ligaments, tendon balancing, and stability. Some recently developed implant arthroplasties of the metacarpophalangeal and proximal interphalangeal joints have anatomically designed articular components; others have non-cemented, press-fit, carefully contoured intramedullary stems. The rationale behind developing the unlinked or semiconstrained prosthesis with anatomic geometry is that it would create balanced forces across the joint. Low-profile, anatomically designed implants limit the amount of bone removed and preserve the integrity of the collateral ligaments. A metacarpophalangeal joint implant with an elliptical metacarpal head and a nonfixed center of rotation can enhance stability in flexion through greater articular contact. A proximal interphalangeal joint implant that preserves the collateral ligaments also can achieve improved stability. Component loosening is not an early complication with these recent designs, and arc of motion is satisfactory.
手部的假体置换必须应对诸如保留侧副韧带、肌腱平衡和稳定性等独特挑战。最近开发的一些掌指关节和近端指间关节植入式关节成形术具有符合解剖学设计的关节部件；其他的则有非骨水泥型、压配式、轮廓精细的髓内柄。开发具有解剖学几何形状的非连接或半约束假体背后的基本原理是，它能在关节上产生平衡的力。外形小巧、符合解剖学设计的植入物可减少骨切除量，并保留侧副韧带的完整性。一种具有椭圆形掌骨头和非固定旋转中心的掌指关节植入物可通过更大的关节接触增强屈曲时的稳定性。保留侧副韧带的近端指间关节植入物也可实现更好的稳定性。在这些最新设计中，部件松动并非早期并发症，且活动弧度令人满意。
