Traction Avulsion Amputation of the Major Upper Limb: A Proposed New Classification, Guidelines for Acute Management, and Strategies for Secondary Reconstruction

Abstract

Major replantation of a traction avulsion amputation is undertaken with the goal of not only the reestablishment of circulation, but also functional outcome. This type of amputation is characterized by different levels of soft-tissue divisions involving crushing, traction, and avulsion injuries to various structures. Between 1985 and 1998, 27 cases were referred for secondary reconstruction following amputation of the upper extremity involving both arm and forearm. Replantation was performed by at least 12 qualified plastic surgeons using different approaches and management, resulting in different outcomes. Initial replantation management significantly affects the later reconstruction. For comparing studies and prognostic implications, the authors propose a new classification according to the level of injury to muscles and innervated nerves: type I, amputation at or close to the musculotendinous aponeurosis with muscles remaining essentially intact; type II, amputation within the muscle bellies but with the proximal muscles still innervated; type III, amputation involving the motor nerve or neuromuscular junction, thereby causing total loss of muscle function; and type IV, amputation through the joint; i.e., disarticulation of the elbow or shoulder joint. Some patients required further reconstruction for functional restoration after replantation, but some did not. Through this retrospective study based on the proposed classification system, prospective guidelines for the management of different types of traction avulsion amputation are provided, including the value of replantation, length of bone shortening, primary or delayed muscle or nerve repair, necessity of fasciotomy, timing for using free tissue transfer for wound coverage, and the role of functioning free muscle transplantation for late reconstruction. The final functional outcome can also be anticipated prospectively through this classification system.

Major upper extremity replantations

“…The published case series are small and there is no scoring system to help with the immediate decisions. The best proposed classification of type of amputation with prognostic significance is that of Chuang and colleagues [3]. Our results support the reliability and importance of this classification.…”

“…Our results support the reliability and importance of this classification. We found that classifying the amputation type based on disruption points of muscles and nerves as proposed by Chuang and colleagues [3], rather than the level of detachment of bone created groups of patients with need for similar secondary surgical procedures and final functional result. In the arm level replantation group only type 2 and 3 injuries were encountered, with almost twice as many secondary procedures performed in the type 3 group.…”

“…According to the classification proposed by Chuang et al [3] only type 2 (4 patients) (figure 1) and type 3 (figure 2) (3 patients) amputations were in the above elbow group (Table 1). At the forearm/elbow level 3 forearms were type 1, 4 forearms type 2, 6 forearms type 3 and 3 were type 4 elbow disarticulation-amputation (Table 1).…”

“…It is a well documented fact that the MESS score is not applicable to hand injuries since even a bad hand is usually better than the available prosthetic substitute [6]. D. Chuang et al [3] proposed a classification of amputation types based on the level of disruption of muscles and nerves rather than bone, assuming that the amount of normally innervated muscle in the proximal stump is the main determinant of later function. According to this classification there are 4 types of major amputations:…”

“…Although survival rate is high, the functional results are guarded [1,2]. The aim of this study is to review our experience with major upper extremity replantations performed between the years 1987-2007 with respect to the type of amputation as proposed by Chuang et al [3]. 23 upper extremities were replanted in 22 patients (7 arms and 16 proximal forearms and elbows).…”