Land Mine Injury: Functional Testing Outcome

Military Medicine, Feb 2004 by Maricevic, Antun, Dogas, Zoran

We present a case of a war patient treated with external fixation for a complex land mine injury involving the fracture of the tibial and fibular bones, which occurred at the front line during the war in Croatia and Bosnia and Herzegovina. Excessive destruction and foreign body penetration into the distal twothirds of the right leg and foot endangered not only the patient's lower extremity but his life as well. Nevertheless, the patient's life, as well as extremity, was saved due to an intensive treatment. A 100-month follow-up showed a bridge callus between the tibia and fibula, tibial bone defects, tibial anterior angulation of 5 degrees, and arthrosis of the right upper ankle joint. Despite a relatively unsatisfactory X-ray finding, the functional testing on the dynamometry system Cybex 300 showed surprisingly good results. There was a satisfactory functional recovery of the treated extremity: the patient could walk without any help even on rocky grounds and was actively involved in his sheep farm duties.

Introduction

War injuries of the extremities are the most frequent (71-77%) 1-3 and are often associated with injuries of other body parts. Lower extremities are more frequently wounded (66%) then the upper ones.4 These wounds usually exert difficult clinical course, require prolonged treatment, and are associated with a high mortality rate.5 Besides the soft tissue injuries, bone fractures are also frequent (32-44%) with bone tissue fragmentation due to its poor elasticity and high specific weight.5-6 This type of wound is characterized by thorn, crashed, and nonvital tissue, disruption of local blood supply, presence of foreign bodies, and microbial invasion through the wound channel. The most difficult wounds often lead to amputations, and a primary goal of early treatment is preserving an extremity. Problems with covering the soft tissue defects, infections, and difficult bone healing are frequent and result in an inadequate treatment outcome. Internal fixation of war wounds is generally inappropriate due to a high risk of infections and disruption of blood supply by bone fragments.7-9 An external fixation is a method of choice that provides a possibility of not only preserving an extremity but also a functional recovery of the wounded leg.10 External fixator is also the safest and simplest means of immobilization during transportation and an excellent choice for definitive fixation of the fracture, especially in a war situation. Its usefulness was proven during the Israeli-Arabian war as well as later wars.11

Case Report

A Croatian soldier (M.D.) was severely wounded at age 41 years by stepping on a land mine at the front line on june 8, 1993. The land mine exploded and injured his right foot and the distal two-thirds of the right lower leg. he received immediate help and was immobilized by Kramer splint for transportation. Approximately 7 hours after being injured, the patient was admitted in a state of hemorrhagic shock to the Emergency Medicine Department at the Split University Hospital. he presented with crushed and destroyed soft tissues, including large defects of the skin, subcutaneous tissue, and muscles. There was an open comminuted fracture of the tibial and fibular bone (Fig. 1, A and B) and a fibular nerve lesion of the right lower leg, but the plantar sensation was preserved. There were also multiple fractures of the foot with foreign body invasion (Fig. 2A). There were multiple explosive soft tissue wounds throughout the body and extremities. Such a difficult war injury was classified as abbreviated injury score V,12-14 Gustilo UIb,15 or 42C3 according to Orthopaedic Trauma Association/Association for the Study of Internal Fixation classification.16 The Mangled Extremity Severity scoring system17 revealed a score of 7, which is an amputation threshold score.18 Because the patient declined amputation as a treatment option, the reconstruction of an injured extremity was attempted. After the hemorrhagic shock treatment with blood and fluids, the Croatian Medical Corps (Instrumentarija, Zagreb, Croatia) external fixation device with unilateral frames in two planes, V-shaped or "delta construction," was used to stabilize the fractured tibial bone. The foreign bodies were partly removed from the foot, the debridement was performed, and the Schanz nail was used for fixation. Skin and soft tissue defects were repaired with the split-thickness skin graft method on june 22 and july 2, 1993. The primarily applied external fixation device was not replaced due to unavailability of the ring external fixators and remained until complete bone healing was reached. Because of prolonged process of bone healing, secondary surgeries were performed on july 19 and August 12, 1993, including a biological stimulation of osteogenesis by autogenous bone graft. The regular follow-up included both clinical and radiological checkups. A superficial "pin" infection, lasting for 4 weeks, developed around the proximal Steinmann nail. It was successfully treated with antibiotics according to the antibiogram. The patient was hospitalized for 5.5 months. Physical therapy started in the hospital and continued in the rehabilitation center in Split for a total of 6 months. The external fixation device was used for 6 months. Functional testing was performed on December 4, 2001, which was 100 months after wounding. The patient walked without any assistance with hardly any noticeable limp in his right leg. he was retired but actively participated in the family business on a sheep farm. There was reduced mobility of his upper ankle joint to 5 to 20 degrees of plantar flexion, abbreviation of the extremity of 2.5 cm, a small degree of atrophy of the right thigh, and the scars remained on the site of reconstructive plastic surgery. The circumference above the upper edge of patella was reduced by 1 cm. The score on the functional testing of his lower extremity by the Hospital for Special Surgery method19 was average (62 of 100). Muscle strength was measured by a dynamometry system Cybex 300.20 The findings included weakening of extensor muscles (quadriceps) and better preserved strength of flexors (hamstrings). The right extensor muscle force was 64% of expected value adjusted to age, sex, and body mass as compared with 80% for the right flexor muscles. Expected values were obtained from the work of Davies et al.21 The muscle strength deficit of the injured extremity versus the healthy one, tested on 60 degrees/s, was 17% for extensors, whereas flexors exhibited higher results by 22% compared with the same muscle group of the left leg. The endurance test with the load of 180 degrees/s resulted in the deficit of extensors of 24%, whereas flexors again sufficed by 14%. Isometric testing under the 60-degree angle during the isometric contraction for 10 seconds showed the deficit of extensors of the injured extremity of 22%. Standard radiological follow-up showed the bone healing with the "bridge calus" between the midthird of tibial and fibular bones, defects of both tibial and fibular bone, anterior tibial angulation of 5 degrees, and degenerative changes of right upper ankle joint (Fig. 1).