الفهرس 
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Abstract
Mallet finger in adults is a traumatic lesion of the terminal extensor band in zone 1, and is characterized by division of the tendon insertion alone (tendinous mallet) or an avulsion of less than one third of the articular surface of the distal phalanx (bony mallet)[1]. The diagnosis of mallet finger is essentially clinical. The patient’s recent history usually includes the likely mechanism of injury. The patient typically presents in an emergency setting or seeks care later, sometimes several weeks after the injury. The patient usually complains of pain and of being unable to perform full active extension of the DIPJ. Upon examination, a passively reducible mallet deformity, swelling, and/or ecchymosis of the dorsal aspect of the DIPJ is found [2]. This injury is commonly seen in ball sports such as baseball and football. The patient is unable to actively extend the digit at the distal interphalangeal joint (DIP joint) and there may be a noticeable droop at the DIP joint [3]. Mallet finger remains a clinical diagnosis that requires a detailed history taking associated to a thorough physical examination of the hand. Imaging studies need to be integrated within the diagnosis, as it is important to exclude any associated bony injuries as well as deformity from osteoarthritis or rheumatoid arthritis. An AP and lateral view x-rays centred at the DIPJ of the affected finger are required these x-rays are used to differentiate between a bony injury and a tendinous mallet injury. Lateral radiographs reveal the presence of volar subluxation of the distal phalanx [4] .
The primary goal in all methods of treatment is restoration of the continuity of injured tendon with maximum recovery of function. Although various treatment protocols have been proposed, splinting of the distal inter-phalangeal joint in extension for 6 to 8 weeks has been the gold standard with minimal morbidity in the majority of patients with closed mallet injury. This can be achieved by thermoplastic stack (mallet) splints or plaster cast splints. With this duration of immobilization patient compliance remains an important outcome factor. It has recently been shown that delay in initiating treatment did not affect significantly the DIP joint movement or extension lag [5 There are a variety of operative fixation techniques described. Closed reduction can be performed by creating an extension block by pinning the fragment with two Kirschner wires [6]. If the injury is reducible by closed means, pinning of the DIPJ in extension should be attempted as this is a simple, cost-effective, and less morbid procedure relative to open treatment. Numerous variants of percutaneous pinning have been described, including the popular extension block pinning for large bony mallets or simple retrograde pinning for tendinous or small bony mallets [7]. Open reduction and internal fixation could be performed using Kirschner wiring, small screws, hook plate, pull-through wires or sutures, figure of eight wiring or bio-degradable screws [8]. A recent study described the use of open reduction and hook plate fixation. The rationale was based on the theoretical advantages of maintenance of anatomic reduction, rigid fixation, and early motion. In comparison to percutaneous extension block pinning, no significant differences in post-operative pain or extensor lag were noted, but hook plate fixation was more expensive and required more soft tissue dissection [Mallet fingers presenting a few months after injury are considered chronic. Treatment options are guided in part by the flexibility of the mallet or the swan-neck deformity and in part by the patient’s anticipated compliance and activities. The available options include prolonged extension splinting, tenodermodesis, central slip tenotomy, or spiral oblique retinacular ligament (SORL) reconstruction [10].