Therapeutic algorithm in a patient with open tibial fracture with extensive laceration of the soft tissue coverage – case report contribution to the discussion about limb salvage

Summary

Open tibial fractures with an extensive laceration of soft tissues are one of many challenges of modern traumatology. Decision to perform a limb-salvage procedure, based upon a complex assessment of the patient’s condition, requires further long-term, multidisciplinary care during the further course of treatment, with uncertain results and high demands for the erudition of the attending team of healthcare professionals, and also psychological endurance of the patient. In our case report, we present the results and individual diagnostic-thera­peutic steps in a patient hurt with a falling tree, with tibial monotrauma.

Keywords:

Open tibial fracture, MESS, case report.

INTRODUCTION

The incidence of tibial fractures is reported at 17-21/100,000 inhabitants, which presents approximately 36 % of all fractures of long bones in adults. Due to the subcutaneous location of the tibia, approximately 15 % of these fractures are open [14]. The decision to perform a limb-salvage surgical procedure is mostly based upon a complex assessment of the patient’s condition, which includes assessing the extent of local injuries, associa­ted life-threatening injuries and risk comorbidities. There are several classification schemes available, which present a helping tool in deciding between a limb-salvage surgery and amputation [2]. During the primary surgery, the prognostically most significant factor for decreasing the risk of possible infection, it is necessary to emphasize early performance of a thorough primary debridement using a high-volume rinsing, optimally in the form of low-pressure lavage. Furthermore, it is important to stabilize the fracture and cover the defects with a high-quality cover of soft tissues [12, 13].

Case report

In October 2010, a 52-year-old male was transported to the Department of Emergency Admission (ER) of the University Hospital Ostrava; the patient had been hurt with a falling tree, and sustained an open tibial fracture with extensive laceration of the skin cover. The patient was intubated upon admission, due to hypothermia (35°C) and hypotension, resulting from the long transport during which the patient had to be carried from the site of the accident to the ambulance. Upon arriving to the ER, the patient’s cardio-pulmonary condition was stabilized, with a level of haemoglobin 92g/l. Dominating was the finding of tibia laceration located posteromedially, with a border-like vitality of the skin cover, and bone fragments visible at the base – see enclosed photographs (Figs. 1a, b).

On clinical findings, periphery of the extremities was bilaterally colder, due to overall hypothermia of the patient, with prolonged capillary refill time; pulsation was palpable only at arteria dorsalis pedis. The injury was classified as AO 42-B2.3, Gustilo IIIb, MESS (Mangled Extremity Severity Score) 6. Retrospectively added scoring – PSI (Predictive Salvage Index) 7, LSI (Limb Salvage Index) 4, NISSA (The Nerve Injury, Ischemia, Soft-tissue Injury, Skeletal Injury, Shock and Age of Patient Score) 9. After administration of antibiotic therapy – Unasyn + Gentamicin and anti-tetanus prophylaxis, the patient was indicated for emergency limb-salvage surgery, without the need of further assessment, due to the local findings and the time interval from the trauma, considering the clear monotrauma.

A thorough debridement of avital muscles (FHL, FDL) was performed at the operating theatre, with removal of a deperiosted bone interfragment and rinsing with jet-lavage, using Betadine^© solution. The fracture was stabilized with an external fixator (EF), and the medial defect was covered with the VAC system (Fig. 2).

Postoperatively, revision of the dorsal tibia was performed, with a finding of pulsating a tibialis posterior and a nerve without any signs of damage; that is why the planned perioperative angiography was abandoned (Fig. 3).

Postoperative care for the patient was provided at intensive care unit, with continuation of the antibiotic therapy, treatment of hypermyoglobinemia, and analgetization therapy using the perioperatively introduced epidural catheter.

In the course of further treatment, changes of the dressings were performed using the V.A.C. method, with gradual necrectomies of the demarking avital skin cover (Figs. 4a, b).

On the sixth day from the injury, conversion of the EF to intramedullary ETN nail coated with cement and Vancomycin. Only the following day (considering the duration of the procedure), a plastic surgeon covered the soft-tissue defect on the medial side. Due to the size of the defect, a free musculocutaneous flap from the same-sided musculus latissimus dorsi was applied. (Figs. 5a, b).

The postoperative course was complicated with an abscess developing under the flap, requiring repeated necrectomies, with administration of the VAC system. After the infectious nidus under the flap was eliminated, the flap was covered with a dermoepidermal graft on the 21^st day, harvested from the thigh of the affected extremity (Figs 6a, b).

After discharge, the patient was repeatedly hospitalized due to fistulas, requiring surgical revisions and sanation of infectious nidi. Due to the repeated fistulas requiring surgical revisions in order to perform sanation of infectious nidi, the patient was referred for PET-CT examination, which showed an infection of soft tissues at the dorsal side of the tibia, without a contact with the ske­leton or any intramedullary findings (Fig. 7).

The transferred flap was lifted, and revision of the fistula, with subsequent repeated changes of the dressings and necrectomies of the demarked necrotic muscles on posterior side of the tibia was performed, with final covering of the granulating defect with Thiersch plasty, using a dermoepidermal graft. Due to the prolonged period of healing of the tibia, dynamization of the nail was performed in the 18^th week.

During the whole course of treatment of recurrent infectious manifestations, repeated antibiotic therapy was administered. The time, means and dose of administered antibiotics were governed by the CRP levels and results of cultures and recommendations of the Antibio­tic Centre. The patient was also undergoing permanent physiotherapy during the whole course of treatment. Full weight bearing was allowed in the fifth month from the trauma. Prevention of deep vein thrombosis during the time of decreased mobility was ensured with admi­nistration of LMWH.

One year after the trauma, radiology examination diagnosed a finding of tibial non-union, with a healed fibula. That is why osteotomy of the fibula was performed, with extraction of the nail, reaming of the medullary canal, and subsequent introduction of a stronger, already uncoated nail.

Four years after the trauma, the patient is able to walk for short distances without any support, with feelings of instability in the area of the ankle (Figs. 9a, b, 10a, b).

The patient complains of swelling and pain during higher loading. Until today, anaesthesia of the 2^nd and 3^rd toe, and hyperesthesia around the calcaneus persist. On current radiograph, a finding of gradually healing tibial non-union and atrophic non-union of the fibula were observed, without any signs of loosening of the osteosynthetic material (Figs. 8a, b).

The total surgical time of the 28 performed surgeries was 28.5 hours; the total length of stay at the hospital was 106 days. The overall costs of care for the patient provided so far have reached 867,167 CZK. The patient is on partial disability pension.

The outcome FADI (The Foot and Ankle Disability Score) score is 39.4 after two years. At present, four years after the injury, the patient is able to move around his flat. Furthermore, he is able to walk up to 1,500 meters on a stable terrain, using a walking stick, and then describes swelling and pain. The patient considers his current condition to be satisfactory.

DISCUSSION AND CONCLUSION

Limb-salvage surgical procedures in patients with open tibial fractures present a complex of partial problems, the high quality and more perspective solutions of which present the most significant advancements in the multidisciplinary specialty of traumatology.

When caring for open fractures, it is recommended, in order to decrease the risk of infectious complications, to remove the primarily placed dressings of the wound only under aseptic conditions at the operating theatre [13].

Considering the fact that the information provided by the paramedic or physician of Emergency Rescue Service are usually limited by the environment of the primary treatment, the time of day and other factors, we perform a primary assessment of open injuries under sterile conditions already at the ER, in order to determine the extent of injuries and timing of further diagnostic-therapeutic procedures.

The most demanding step in the whole algorithm of caring for patients with open tibial fractures type IIIc according to Gustilo is the decision about amputation or limb-salvage procedure. Several scoring systems have been proposed, which utilize certain variables in order to define the border of meaningfulness of possible limb-salvage procedure [2, 4, 16]. MESS score, first published in 1990, remains the golden standard; excceding the level of seven points is an indication for amputation [4]. The primary popularity of this score is based upon its simplicity, and the possibility to achieve a rapid pre­operative assessment. When compared to other scoring systems, the MESS score is considered less complex. Upon comparing the scoring systems used in clinical practice today (LSI, PSI, NISSA, MESI), none of these systems has been shown to be sufficiently predictive for the decision-making between amputation and limb-salvage procedure [2]. Most of these classifications were created ten or more years ago, and the predictive potential of individual criteria has been weakened or even denied with the onset of newly used osteosynthetic implants and procedures used for reconstruction of the soft-tissue cover, as well as with the immediate availa­bility of a multidisciplinary team [2]. On the other hand, individual scoring systems do not have a mechanism for distinguishing patients who are at internal and psychosocial risks for limb-salvage procedures. Even the absence of plantar sensitivity, which used to be an indication for amputation in the past, is not considered to be an obstacle for limb-salvage procedure according to Bosse. Clinical trials performed lately define the extent of soft-tissue injury to be the most significant variable [10]. In the decision-making process, the attempt to preserve the limb is not dominant; it is the attempt to preserve a functional limb. When comparing two cohorts of patients, the limb-salvage procedures were associated with a higher occurrence of complications, requiring repeated surgical procedures, more expensive medical care and longer physiotherapy [3]. However, according to a meta-analysis performed by Akula, the patients with a salvaged limb present a more satisfied group in this comparison [1]. In the case of our patient, the scoring systems presented a borderline indication for limb-salvage procedure; according to expert literature, the biggest problem of the procedure was the extensive laceration injury of the soft-tissue cover [10].

The quality of primary debridement, and the speed of its accomplishment, ideally within six hours from the trauma, is considered in the literature to be the most important prevention of infectious complications. By removing the breeding ground in the form of necrotic tissue and foreign bodies, we reduce the amount of microorganisms by 80 % [13]. It is optimal to perform the primary wound treatment within six hours from the injury [13]. The most suitable method today is considered to be 
a low-pressure rinsing, using the pressure below 50psi (approx. 350 kPa), which is associated with a lesser risk of destructing the bone and surrounding soft tissues. Also the risk of transferring the bacteria into deeper parts of the medullary canal is not so great. According to some studies, the Betadine^© preparation in 1 % dilution decreases the risk of infection [6].

Antibiotic therapy in patients with open fractures is defined by standards of individual hospitals. At our centre, we use empiric administration of penicillin-line anti­biotics (Unasyn^©), and Clindamycin (Dalacin^©) in patients who are allergic to penicillin, for the period of 7–10 days, with a subsequent change upon the occurrence of infectious complications, depending on the smear test results. Double-antibiotic combination is used in patients with significantly soiled wounds and open fractures type III. A meta-analysis performed in 2016 claims that a long-term administration of antibiotics does not decrease the risk of infection; on contrary, it increases the risk of resistance. It is recommended to administer the antibiotics (penicillin or cephalosporin) every 8 hours until the soft-tissue defect has been closed, for the maximum period of 72 hours, and another single dose with every large surgical procedure. It is also re­commended to add a single dose of gentamicin during the initial treatment. Early and final solution of the destructed soft-tissue cover is considered to be one of the main priorities [7, 13].

In our patient, primary tibial stabilization was performed using an external fixator, considering the timelessness of the procedure, the degree of soft-tissue comminution and the risks of infection. Early conversion to internal fi­xation was performed within the timeframe recommen­ded in expert literature, i.e. seven days; in order to prevent possible infectious complications, a nail coated with cement containing dissolved Vancomycin was used. The primary indication for using the coated nail includes active intramedullary infections of long bones. A significant advantage may be seen in the high concentration of the dissolved antibiotic, not depending on the quality of local perfusion, filling of the dead space and stabilization of the fracture or instable non-union. Due to the minimal risks concerning toxicity or development of resistance towards the used antibiotic, using the coated nail presents 
a suitable alternative, and also serves as a preventive measure [17, 18].

The problems of covering soft-tissue defects, i.e. selection of a suitable flap, and adding the procedure into the sequence of procedures linked one to another, need to be discussed between the traumatology and plastic surgeons, and present another attribute in the multidisciplinary care provided for these patients. The role of soft-tissue cover is not limited to mere prevention of drying of the wound and possible infection. Soft tissues also participate upon the healing of often deperiosted bone fragments, as a source of progenitor cells, growth factors and vascular supply [5]. Although there currently exist tendencies to use a rotational flap plasty rather than other types of flaps, in our case, the selection of a free flap from musculus lattissimus dorsi presented a suitable option, considering the extent of primary injuries [5].

Contrary to literary sources preferring an acute performance of a flap plasty, this recommendation presents a practical problem in most hospitals, namely in the form of an absence of permanently available surgical team, capable of performing free flap plasties, and also due to the frequent coincidence of open fractures of long bones in patients with a polytrauma, who primarily require treatment of life-threatening injuries. In these cases, suitable alternatives include some of the techniques of temporary covering of the lost soft-tissue cover. A suitable alternative in these patients may be some form of a vacuum system, which enables aspiration of accumulated secretions, decreasing of infectious complications and stimulation of granulation [9, 15]. Decreasing the interval required for suturing of the wound has been manifested when paired with elastic ligatures [8].

Other partial procedures (treatment of infections and non-unions) presented only a common practice of mana­gement of complications occurring in the course of follow-on care for the traumatology patient.

The economical factor enables a comparison with fo­reign literature sources only, when the consideration of financial costs is, due to the commercial insurance, an important variable when deciding about further care. A two-year comparison of economic costs related to care for patients after amputation or reconstruction did not differ significantly, and presented the sum of $91,106 and $81,316, respectively. Calculation of anticipated life-long costs showed a threefold higher costs of medical care in amputated patients when compared to patients with a reconstructed extremity, $509,275 and $163,282, respectively [10].

The assessment of the overall outcome by the patient as acceptable does not correlate with the outcome FADI score but presents more likely a personal satisfaction of the patient from salvaging the limb, regardless of the current functional alteration. The result confirms the dominating psychical satisfaction with the outcome of surgery in patients after reconstruction procedures [1]. This observation is contradictory to the not so satisfactory results assessed by Boss after two years, when 40% of patients in both groups were classified as patients with significant disability on the Sickness Impact Score [3].

Our presented case-report offers yet another confirmation of the fact that limb-salvage procedure in open tibial fractures type Gustilo IIIc usually presents a long-term, multidisciplinary therapeutic process, with possibly suboptimal results.