Key Words
neck burn, contracture, mentosternal contracture, skin grafts, neck flaps, head and neck burns, neck reconstruction, facial burn reconstruction
Synopsis
Contractures of the neck are common sequelae of neck burns, even in centers with ideal facilities, let alone in circumstances with limited resources. Among the classifications put forward, Achauer and VanderKam’s classification of neck contractures are the one most commonly followed. The goal of surgery for neck burn contractures is to create a mobile and supple neck. Early excision and grafting, where required, with splinting and physiotherapy, have been able to minimize contractures, yet there are large numbers of patients with neck burn contractures ranging from mild to extensive who require appropriate surgical interventions to correct their deformities. Anesthetic concerns are primarily for airway access and patency.
Reconstructive options for the neck contractures are discussed, and the chapter gives the author’s step-by-step procedure for the release of an extensive mentosternal contracture, along with the procedure for resurfacing with full-thickness skin grafts. Adequate post-operative care with long-term splinting must be ensured to achieve good results.
Clinical Problem
Presentation
Reconstruction of burn injuries of the neck poses a great challenge. Its successful treatment requires a thorough understanding of the regional anatomy, the pathophysiology of the burn wound, and the vector forces working on the healing burn wound. The reconstruction demands sound judgment and good technical expertise of the persons coming forward to treat the patient. While accepting the fundamental limitations of replacing one variety of scar by another, one must set the goal of reconstruction in this region to be a significantly improved functional and esthetic result.
The basic principle of burn management with early excision and grafting is the key to preventing neck burn contractures. In places where resources are limited, the burn wounds of the neck often end up with healing by secondary intention or delayed grafting. Burn contractures of the neck present in various forms depending on their severity. They present from linear scars to those encompassing the whole of the front of the neck. They range from mild restrictions to the extension of the neck to the very severe form of mentoclavicular contractures.
Achauer and VanderKam classified neck burn contractures on the basis of involvement of the percentage of anterior surface of the neck ( Fig. 4.5.1 ). The disadvantage of this classification is that it does not identify the status of the surrounding tissues and their availability for reconstruction. It also does not describe posterior neck burns ( Fig. 4.5.2 ). Onah in his study of 41 post-burn mentosternal contractures in the National Orthopedic Hospital, Nigeria, suggested a new classification system that takes into account the availability of surrounding non-burned tissue for reconstruction. This serves as a helpful guide for the choice of reconstructive procedures.
McCauley gives a separate grading of neck contracture based on the mobility of the neck. Whatever classification is followed, it is appreciated that neck burn contractures bring about limitations in the activities of daily life, and early reconstruction of neck burns or their contractures must be carried out. Makboul and El-Oteify also have a classification for neck contractures that combines the width of the contracting band and the degree of mobility at the cervico-mental angle.
Etiology
Burns of the neck are commonly sustained from fire, though they may happen from other causes such as electricity, hot water, oils, or steam.
Flame burns are fairly common, and the head and neck region can be the worst affected. Contractures of the neck are common sequelae of burns of the region. Even in countries with ideal facilities and institutional care, post-burn neck contractures are not uncommon.
Though less common, scald injuries cause burns of the head and neck and chest region, particularly so in children. Homicidal chemical burn (acid) injuries, though less common, are also an important cause of severe neck contracture. Instances of suicidal burns are also to be found in these regions.
Associated Conditions
Burns of the neck are usually not an isolated condition. Associated burns of the face and chest are extremely common, and they tend to modify the management plan in terms of priority and timing. Burns of the neck, when associated with burns of the face, may be associated also with ectropion of the eyes and mouth. Perioral burns may cause microstomia and an added difficulty for intubation. Comorbid conditions depending on the age of the patient need to be assessed and addressed during the acute phase.
Pre-Operative Management
Physical Examination and Key Anatomy
It is important to review the treatment that the patient received during the acute phase of burn management. Did the patient receive early excision and grafting, or has the contracture developed as a sequela of secondary healing of a deep dermal or full-thickness burn? The approach to the two situations is different. In the first situation, the approach is more conservative, and the scars are allowed to mature before any intervention. In the latter situation, it is important to assess the amount of tissue lost and whether it warrants early replacement.
In addition to evaluation of the scars and their nature and thickness, the pre-operative physical examination requires an evaluation of the extension at the atlanto-occipital joint.
Pre-Operative Testing Needed
A complete blood count and hemoglobin status are required. Any intervention with a hemoglobin status below 10 g/dL should be avoided. This operation may have significant blood loss.
Bleeding and clotting time, along with prothrombin time, is needed. Patients with an increased tendency to bleed must be carefully evaluated before surgery is embarked upon. A total protein profile, if possible, will allow assessment of nutritional status.
A plain radiograph of the neck with AP and lateral views may help to delineate the tracheal position, deformity, and deviation, if any.
Comorbid factors must be identified, and additional pre-operative testing along those lines are imperative. Beware of unidentified or suppressed conditions that could put the patient in danger due to the surgery.
Optimal Timing of Surgery
Apart from situations where deep burns of the neck demand early surgical intervention, neck burn reconstruction is often carried out after the burn wounds have closed and scar maturation is progressing. It is surprising how often wounds allowed to heal spontaneously end up with acceptable results.
Supplies Needed
Table 4.5.1 outlines the supplies that would be a desirable addition to the standard supplies of an operating theater.
Dermatome—hand/electric |
Autoclaved furniture foam, 1-in. thickness |
Tulle gauze with or without chlorhexidine |
Skin staples |
Vicryl sutures 3/0, 4/0 (curved cutting needle) |
Silk sutures (for bolster tie-over stitch) 1/0 |
7.5% sodium bicarbonate injection—2 × 10-mL vials |
Epinephrine 1 in 1000—1 ampule |
Lidocaine 2%—1 × 30-mL vial |
Ringer’s lactate/normal saline solution—500 mL |
Plaster of paris/fiberglass rolls, 3-in./6-in. |
Large dressing gauze |
Cotton bandage rolls, 3 in./6 in. |
Anesthesia Concerns
The major anesthetic concerns in patients with face, head, and neck burn contractures are airway patency and distortion of normal anatomy.
Post-burn scar contractures of the neck produce extension restrictions varying from mild to very severe flexion contractures. This poses intubation difficulties and is the major anesthetic concern. The problem is not only in the severe limitation of extension but also in the associated facial burns producing microstomia, limiting access to the larynx and trachea. Additionally, the contracting forces of the healing burn wound tend to bring about deformities in the normal laryngo-tracheal anatomy and thereby further cause difficulty in intubation.
The availability of fiber-optic bronchoscopes has overcome the problem in centers where they are available, but in others, the practice is quite different. Although blind nasal intubation is still practiced in some centers, the most common practice is to divide the contracture under a local anesthetic with or without associated ketamine anesthesia. The adequate release of contracture is followed by endotracheal intubation and the formal reconstructive procedure.
Agarwal preferred to complete the reconstruction under tumescent and ketamine anesthesia with good results. The author advocates the use of a laryngeal mask as an alternative to intubation for the entire reconstructive procedure.