Consideration for Limb Salvage in Place of Amputation in Complex Tibial Fracture With Neurovascular Injury: A Case Report

Abstract

High-energy tibial fractures often present with associated soft tissue injuries, including neuro-vascular damage, complicating the treatment decision. A 33-year-old male presented with Gustilo Anderson type IIIA fracture of the left distal tibia and fibula with associated closed calcaneus fracture and tibial nerve transection. Amputation was discussed, but the decision was made for limb salvage with nerve allograft. The patient displayed satisfactory functional recovery at 29 months postoperatively without need for major revision, grafting, arthrodesis, or amputation. This case report provides an example of successful limb salvage utilizing tibial nerve allograft in a complex high-energy lower extremity injury.

Level of Evidence: IV

Introduction

Management options for open, high-energy distal tibia fractures with associated neurovascular injury remain highly controversial, as current literature suggests either amputation or limb salvage with neither yielding significantly greater outcomes.^1,2 Amputations are far more common in this setting, having demonstrating outcomes leading to fewer reoperations and hospitalizations.^3,4 The choice between amputation or limb salvage largely rests on surgeon judgement and shared-decision making with patients, and is influenced by numerous factors including patient’s preinjury status, associated soft tissue damage, injury location, resources available, and patient wishes.¹

High-energy tibial fractures often present with associated soft tissue injuries, including neurovascular damage, complicating decision making. In the context of nerve transection, amputation is strongly considered over limb salvage with complex nerve reconstruction.³ Compared to that of the upper extremities, the literature on outcomes following allograft nerve reconstruction in the lower extremities is limited and remains controversial. In a study evaluating the rate of meaningful recovery of nerve repairs in different regions of the body, Safa et al. found that 53% of patients with repair of lower extremity nerves experienced meaningful recovery, defined as Medical Research Council Classification (MRCC) sensory and motor scale ≥ S3/M3, versus 100% and 83% in the head/neck and upper extremities, respectively.⁵ With the recovery rate of lower extremity nerve repair significantly lower than that of other regions, and amputations potentially yielding fewer complications and faster recovery, amputation is a reasonable treatment.⁴

However, with recent advances in surgical care, the possibility of limb salvage with nerve allograft reconstruction should not be immediately excluded in favor of amputation, as it can potentially yield similar or improved outcomes.³ Here we describe a patient with a high-energy tibial fracture and associated tibial nerve transection who experienced satisfactory outcomes following limb salvage and tibial nerve allograft reconstruction.

The patient described in this case report was informed that their case would be submitted for publication and provided verbal consent.

Case Report

A 33-year-old male roofer presented to the emergency department at our university-associated level-one trauma center following a fall from height while working. The patient sustained a Gustilo-Anderson type IIIA fracture of the left distal tibia and fibula, as well as a closed calcaneus fracture, among other injuries (Figure 1a, b, c). Physical examination was significant for a 2cm posterolateral wound over the left lower extremity with exposed tibial bone fragments. He had a palpable dorsalis pedis pulse. Sensation to light touch was intact in the saphenous, sural, and superficial peroneal nerve distributions, but noted to be absent over the plantar foot and first webspace of the dorsal foot. He exhibited no active plantarflexion or dorsiflexion at the ankle.

Figure 1A-1E.

Anteroposterior (A) and lateral (B) radiographs of left ankle and lateral radiograph of the foot (C) demonstrating comminuted intraarticular distal tibial, fibular, and calcaneal fractures. Intraoperative image of tibial nerve and posterior tibial artery transection (D) and tibial nerve allograft placement (E).

Within 8 hours of presentation, the patient was taken to the operating room (OR) for wound exploration, irrigation, debridement, and external fixation of the distal tibia. The posterior tibial artery and tibial nerve were found to be completely transected upon exploration of wound (Figure 1d). The neurovascular bundle was identified, noted to be bleeding, and ligated with suture.

Following his initial surgery, amputation of the limb was strongly considered given his neurovascular injury, however, limb salvage was pursued at the strong desire of the patient and presence of intact sensation to the extremity. After 72 hours after his initial surgery, perfusion to the foot remained and he returned to the OR for tibial nerve reconstruction using allograft. This was performed under microscopic guidance by a microsurgery-trained orthopaedic hand surgeon. Debridement of the open fracture site was repeated, and both ends of the transected tibial nerve were identified. Portions of the nerve were resected until healthy, budding fascicles were observed. The patient’s tibial nerve was noted to be large, spanning 10mm in diameter with two separate nerve anastomoses. Therefore, the initial 5 x 70mm nerve allograft was cut in half and two separate allografts were utilized to reconstruct the nerve with 8-0 nylon suture, resulting in a 3cm graft gap (Figure 1e). Once the allograft was in place, minimal tension on the nerve was ensured and two submucosal nerve protectors were utilized. After wound closure, the foot remained well perfused.

Four days following tibial nerve allograft, revision fixation of the left distal tibia and fibula were performed. Fibular fixation was achieved using a 3mm flexible intra-medullary rod, while the articular segment of the distal tibia was reconstructed using a 4.0 cannulated screw. A 3-ring circular frame with hind foot extension was used to span the tibia and calcaneus fractures in order to maintain alignment. The minimally displaced calcaneus fracture was fixated to the frame with two crossed tension wires, allowing for maintenance of reduction.

At two months postoperatively, the patient was ambulatory and reported sensation to light touch over the lateral left foot. At seven months, further improvement of sensation was observed, however, imaging revealed lack of appropriate bone healing. Results of a bone biopsy were negative for infection. The external frame was removed at this time, the fracture was debrided, and a spacer was placed at the tibial defect site. At 20 months postoperatively, radiographs demonstrated appropriate interval bone healing and the patient returned to limited work duties with slight pain during active ankle motion. He was provided with a dynamic ankle orthosis, which does provide additional comfort and support. At 22 months from his injury, protective plantar sensation had returned. At 29 months, maximal medical improvement was determined.

Although he continued to experience limited range of motion at the ankle and ambulates with an antalgic gait, the patient attained his treatment goal - to be ambulatory on a salvaged limb rather than amputation. The tibial fracture demonstrated healing on radiology, and the patient had a functional lower extremity with intact sensation and motor function of deep peroneal, superficial peroneal, tibial, and sural nerves (Figure 2). There were no clinical indications of infection, and the patients is able to work 2-3 hours per day in a strenuous occupation.

Figure 2A-2D.

Anteroposterior (A) and lateral (B) radiographs at 4 years postoperatively demonstrating well healed fractures. Clinical image of patient demonstrating dorsiflexion (C) and ambulation (D).

Discussion

We describe a Gustilo-Anderson type IIIA distal tibia and fibula fractures, closed calcaneus fracture, posterior tibial artery injury, and tibial nerve transection. Given the patient’s severe soft tissue damage, neurovascular injury with loss of plantar sensation, and prolonged ischemia (>6 hours), there were strong indications for amputation.^1,3 Although absence of plantar sensation remains a controversial contraindication to limb salvage,^2,6 a confirmed tibial nerve transection is widely considered contraindicative for limb salvage due to a loss of protective foot sensation and functional foot musculature.^1,4 In their analysis of 527 patients with mangled lower extremity injuries, MacKenzie et al. found that soft tissue injury and plantar foot sensation were the most important predictive factors of successful limb salvage.⁷ Even when tibial nerve grafting is attempted to restore plantar sensation, Nunley et al. demonstrated poor functional nerve recovery or prolonged recovery time.⁸ In the first long-term prospective study comparing amputation to limb salvage after severe lower extremity injury, Bosse et al. demonstrated no significant difference in functional outcomes at two years postoperatively.¹¹ The authors did report a significantly greater rate of complications, reoperations, and repeat hospitalizations in patients undergoing reconstruction. However, this literature does not account for recent improvements in surgical techniques nor improved understanding of these injuries and inadequately evaluated patient quality of life.¹² The recent literature provides improved outcomes in these cases, in part due to further understanding of the injuries and reconstruction techniques. Important technical considerations in nerve reconstruction include reducing allograft tension, shortening gap lengths,^5,9 and resection of the damaged nerve which is noted by bleeding within the budding fascicles.⁸

Currently, we have a better understanding of outcomes of allograft nerve reconstruction. The literature displays consistently satisfactory outcomes despite a lack of clarity on the indications for repair or reconstruction.^5,13 In a case series of traumatic lower extremity injuries with tibial nerve lacerations, Momoh et al. found that while patients treated with tibial nerve allograft experienced mild pain and decreased ankle range of motion, they were able to become ambulatory without aids and experienced minimal disability when performing daily activities.²

The meta-analysis by Garg et al.¹³ reported that 81% of nerve graft reconstruction cases achieved good outcomes across a heterogenous sample of tibial nerve injuries. Kurozumi et al.¹⁴ reported significantly higher functional and mental health scores in severe lower extremity fracture cases treated with limb salvage compared to amputation at a minimum of nine months postoperatively.

Other studies have demonstrated similar results further supporting nerve reconstruction.⁹ Consistent with these findings, our patient achieved satisfactory results with evidence of functional nerve recovery within 6 months postoperatively with presence of plantar sensation, adequate bone healing on imaging, and ability to ambulate. The patient regained protective plantar sensation and with extensive physical therapy, returned to limited work duties within 20 months of surgery. Severe open tibial fractures are often associated with high infection and malunion rates resulting in subsequent procedures and prolonged recovery time.⁶ However, in addition to a satisfactory functional result, the current case did not result in infection or major complication.

Given the complexity of this case and limited resources of our hospital, amputation could have been implemented and most likely resulted in a shorter recovery process with an acceptable functional outcome. However, this undermines the preferences of the patient, who expressed strong desire to pursue limb salvage over amputation. Furthermore, he possessed the resources to pursue more complex surgical management, which likely contributed to his favorable outcome. Ultimately, the patient remains pleased with his treatment course and is extremely delighted about having a functional limb rather than a prosthetic.

The strengths of the current case presentation are the clinical term of follow up, and the thorough description of treatment which provided excellent functional recovery despite the severity of injury. Amputation is a reasonable option in these complex cases. This information is intended to add to the literature regarding these complex injuries.

In conclusion, this case report provides an example of successful limb salvage utilizing tibial nerve allograft in a complex high-energy lower extremity injury.