Arvind Varun, Hong Daniel Y, Strauch Robert J
Columbia University Medical Center, New York, NY.
JBJS Essent Surg Tech. 2024 Oct 22;14(4). doi: 10.2106/JBJS.ST.23.00082. eCollection 2024 Oct-Dec.
Extensor tendon injuries are a common condition that hand surgeons must be prepared to treat. The area of extensor tendon injury can traditionally be broken down into 9 zones. Physical examination is the best way to diagnose extensor tendon injury with a loss of active extension in the injured digit. The tenodesis effect may be utilized to aid in diagnosis: wrist flexion should cause passive extension at the metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints if the extensor tendon is in continuity.
Repair of extensor tendon injuries depends on the zone of injury and the thickness of the tendon, which determines its ability to hold core sutures. For zone-I and II injuries, several "figure of 8" buried sutures can be utilized or a running type of suture may be employed. For zone-III to VII injuries, 1 or 2 core sutures and a supplementary running suture can be utilized.
Several alternative techniques have been previously described. These include variations in the number of core strands, repair configuration, and suture caliber, as well as the use of epitendinous repair. Alternative treatments also include nonoperative treatment, which is typically reserved for partial tendon injuries and for patients who are unable to tolerate a surgical procedure.
The techniques that we describe are tailored to the thickness of the tendon. Running sutures are applicable to any zone, whereas core sutures are best utilized in zones III through VII. The running interlocking horizontal mattress technique has been found to be stiffer and faster to accomplish compared with the other techniques, and was found to have good to excellent clinical results in a study of lacerations in zones IV and V.
Repair of extensor tendon lacerations has demonstrated good long-term outcomes if performed in a timely manner after injury. A previous study showed good to excellent function in up to 64% of acute extensor tendon repairs, more fingers lost the ability to flex fully than lost the ability to extend. Systematic reviews have suggested that dynamic rehabilitation may not provide superior long-term benefit compared with static splinting.
The Elson test should be performed under a digital nerve block in order to properly assess the integrity of the central slip.In distal zone I and III injuries, suture anchors or bone tunnels may be utilized when there is no remaining tendon on the distal end of the laceration.When preparing the tendon ends for repair, it is important to handle the tendon delicately-preferably through the cut end of the tendon rather than the tendon itself.In zone-VII injuries, the injured tendon may lie beneath the extensor retinaculum. In such cases, windowing of the extensor retinaculum may decrease adhesion formation and facilitate repair.
MCP = metacarpophalangealPIP = proximal interphalangealDIP = distal interphalangealIP = interphalangealROM = range of motionRMS = relative motion splintRIHM = running interlocking horizontal mattress.
伸肌腱损伤是手部外科医生必须准备好治疗的常见病症。传统上，伸肌腱损伤区域可分为9个区。体格检查是诊断伸肌腱损伤的最佳方法，损伤手指会出现主动伸直功能丧失。可利用“动力腱固定效应”辅助诊断：若伸肌腱连续，腕关节屈曲时应引起掌指关节、近端指间关节和远端指间关节的被动伸直。
伸肌腱损伤的修复取决于损伤区域和肌腱厚度，肌腱厚度决定其容纳核心缝线的能力。对于Ⅰ区和Ⅱ区损伤，可采用数根“8”字埋线缝合或连续缝合。对于Ⅲ区至Ⅶ区损伤，可采用1或2根核心缝线及补充连续缝合。
先前已描述了几种替代技术。这些包括核心缝线数量、修复构型、缝线直径的变化，以及腱周修复的应用。替代治疗还包括非手术治疗，通常适用于部分肌腱损伤以及无法耐受手术的患者。
我们描述的技术是根据肌腱厚度量身定制的。连续缝合适用于任何区域，而核心缝线最适用于Ⅲ区至Ⅶ区。与其他技术相比，连续交锁水平褥式缝合技术更坚固且完成速度更快，在一项关于Ⅳ区和Ⅴ区撕裂伤的研究中发现其临床效果良好至极佳。
伸肌腱撕裂伤若在损伤后及时修复，已证明具有良好的长期效果。先前的一项研究表明，高达64%的急性伸肌腱修复功能良好至极佳，更多手指丧失完全屈曲能力的情况多于丧失伸直能力的情况。系统评价表明，与静态夹板固定相比，动态康复可能不会带来更好的长期益处。
应在指神经阻滞下进行埃尔森试验，以便正确评估中央束的完整性。在远端Ⅰ区和Ⅲ区损伤中，当撕裂伤远端没有剩余肌腱时，可使用缝线锚钉或骨隧道。准备肌腱断端进行修复时，小心处理肌腱很重要——最好通过肌腱断端而非肌腱本身进行操作。在Ⅶ区损伤中，受伤肌腱可能位于伸肌支持带下方。在这种情况下，切开伸肌支持带可减少粘连形成并便于修复。
MCP = 掌指关节；PIP = 近端指间关节；DIP = 远端指间关节；IP = 指间关节；ROM = 活动范围；RMS = 相对运动夹板；RIHM = 连续交锁水平褥式缝合
