The halo-shoulder brace and the mandibular-shoulder brace as postoperative supports following spinal fusion.
N. Van Kempen De Witte *
Abstract
Bracing of the cervical spine in patients with rheumatoid arthritis, ankylosing spondylitis and instability due to metastases poses special problems.
Because of asymmetry, a tender bony or cutaneous swelling or tender skin, difficulties arise in fitting a mass-produced brace.
In order to overcome these difficulties a carefully moulded made-to-measure halo-shoulder brace and also a mandibular-shoulder brace were developed.
The halo-shoulder brace (a halo connected with 4 rods to a shoulder girdle) provides an effective means of postoperatively controlling the unstable cervical spine until the graft unites. The brace is well tolerated by the patient and facilitates early postoperative mobility.
The mandibular-shoulder brace (a similar shoulder girdle with a mandibular and an occipital part), also well tolerated by the patient, is used after the halo-shoulder brace during consolidation of the graft and also to support the neck in patients who for other reasons require a collar but who cannot tolerate a normal ready-made appliance.
The manufacture of the braces, their effectiveness and a series of 13 patients are described.
Introduction
Cervical fusion is often necessary for the treatment of instability due to rheumatoid arthritis, metastatic destruction of part of the cervical spine or trauma and is routine following cervical osteotomy for correction of deformity in ankylosing spondylitis. The relief of pain is also an important reason for operation especially in patients with metastases.
Early postoperative mobilization of the patient with rheumatoid arthritis or ankylosing spondylitis is desirable in order to maintain general mobility and of the cancer patient to avoid a considerable portion of a limited life expectancy in traction. Although not essential early safe mobilization of the trauma patient is also desirable. It has been our recent practice to support the cervical spine during the first 6-12 weeks, until the graft has united, in a halo-shoulder brace and thereafter, to protect the neck, in a mandibular-shoulder brace whilst consolidation of the graft progresses. However, bracing of the cervical spine in patients with rheumatoid arthritis, ankylosing spondylitis and instability due to metastases poses special problems.
In the patient with rheumatoid arthritis;
- the neck is often short (with a squashed appearance) due to collapse of cervical vertebrae)
the chin is often small
the neck, shoulder and upper torso are often asymmetrical
collarbones and shoulder blades are often unduly prominent
the skin is thin and easily damaged
there may be rheumatoid nodules
sweating is often excessive
the cervical spine is often painful
cervical instability often has to be controlled at more than one level
there is a posterior midline scar.
In the patient with ankylosing spondylitis following corrective osteotomy or treatment of a fracture;
The patient with metastatic destruction of the cervical spine may exhibit;
asymmetry of the neck due to tumour tissue
asymmetry of the upper torso, for example following a mastectomy
tenderness of irradiated areas
cutaneous or superficial bony metastases which must be taken into consideration.
In order to overcome these problems two made-to-measure orthoses were developed two years ago; the halo-shoulder brace and the mandibular-shoulder brace. These braces are made individually for each patient in order to obtain a comfortable appliance with the best possible fit and to provide effective stabilization of the cervical spine. From our previous experience with cervical braces and collars we concluded that a new orthosis must be light and the contact with the shoulder and neck area must be spread out as much as possible in order to avoid pain or pressure necrosis of the vulnerable skin. When immobilizing the neck it is essential that the mouth, larynx and arms remains as free as possible so that the general mobility of the patient is maintained. The orthosis has to be easily removable and replacable to facilitate personal hygiene, wound care and irradiation treatment.
Construction of the orthoses
Plaster model
Both orthoses are constructed on a plaster model which is made before the operation, if possible with the patient in a sitting position. Before the plaster is applied, the following points are marked on the patient;
the middle of the chin
the suprasternal notch
the xiphoid process
both clavicles
the acromioclavicular joint
the thyroid cartilage
spinous processes from C1 to T5
superior and medial borders of the scapulae
the spines of the scapulae
any other prominent bony points, cutaneous nodules or painful areas.
The skin is smeared with release agent except for the marked areas and the hair is held out of the way in a piece of tubigrip or tubular bandage. A plastic tube is placed on each side of the head and shoulder to facilitate cutting the cast. The plaster of Paris is then applied around the neck from just below the lower lip, over the ear lobes to the occipital protuberance and downwards to the xiphoid process and to the 5th thoracic spinous process. During the application of the plaster the head is held in neutral rotation with the nose and the marks on the chin, the suprasternal notch and the xiphoid process maintained in one vertical line. Furthermore the head is maintained in a neutral horizontal position with the inferior orbital margins and the external auditory meati in the same horizontal plane. The arms should hang freely by the side of the body. The plaster is then allowed to dry.
The positions of the plastic tubes are marked on the plaster and a few horizontal lines marked over the vertical tube line to facilitate reassembly. The cast is cut with a cast saw on the marked tube lines on both sides. This negative plaster of Paris is then reassembled. After greasing, the inside is filled with plaster of Paris in order to produce a positive cast. On the positive cast an extra 4mm of plaster is added over the following areas;
The halo-shoulder brace
Fig. 1 shows the materials necessary for the construction of a halo-shoulder brace.
Two paper patterns are made so that the resulting shoulder brace will reach from T1 to T4 and rest on the skin between the spinous processes and the shoulder blades. Anteriorly the brace reaches from the suprasternal notch to the xipoid process. The brace passes over the shoulders, between the root of the neck and the acromio-clavicular joints which are left free.
With the aid of the paper patterns, the anterior and posterior parts of the brace are sawn out of 3mm orthopaedic Plexidur. The edges of the Plexidur are smoothed round with a sander and both sides are matted with fine wet and dry sandpaper for a more aesthetic effect.
Using the same patterns, the anterior and posterior linings are cut out of 6mm Plastazote. The anterior and posterior paper patterns are glued together along one shoulder edge and with this single pattern a one-piece inner lining is cut out of 1cm soft sorbo rubber. Velcro fasteners are then sewn on to the free shoulder edge of the sorbo rubber lining in order to hold it in place under the shoulder brace.
The anterior and posterior parts of the brace are moulded separately. First, the Plastazote is heated and moulded on the positive plaster cast followed by the Plexidur, which is moulded on top of the Plastazote. The Plexidur layers are glued on to the Plastazote layers and the edges are smoothed with the sander. The lower edge of the anterior part of the brace is bent outward slightly so as not to press painfully on the skin over the xiphoid when the patient is in a half-sitting position. The anterior and posterior components of the halo-shoulder brace are then trial fitted on the patient over the sorbo rubber lining and any necessary minor modifications carried out. The straps, buckles and leather tongues for holding the anterior and posterior elements of the brace together are next fitted to the brace. With the shoulder brace in place on the patient the positions for the attachment pieces of the halo connecting rods are marked. The halo connecting rods should be vertical and symmetrical. The anterior connecting rods should be as wide apart as possible so that the visual fields are not restricted, rhe anterior connecting rods are fixed to the Plexidur brace on a line approximately 3.5cm below the level of the suprasternal notch. The posterior connecting rods usually pass from the most posterior side holes on the halo and are screwed directly on to the brace just under the level of the spines of the scapulae.
In order to simplify removal and reassembly the unused side screwholes in the halo are covered with sticking plaster. For the same reason there is only one fixation hole in the leather shoulder strap.
A complete halo-shoulder brace should appear as in Fig. 2 . With the brace in place X-rays are made to check whether the position of the cervical spine is satisfactory.
The mandibular-shoulder brace
Fig. 3 shows the materials necessary for the construction of the mandibular-shoulder brace. The paper patterns are made so that the resulting brace will support the ramus of the mandible whilst the thyroid cartilage remains free. The brace reaches down to just above the xipoid process and is bent outward similar to the halo-shoulder brace. The occipital part supports the head just behind the ears. The brace reaches from the occiput down to T4.
This brace is also made out of 3mm orthopaedic Plexidur and 6mm Plastazote, which are moulded on the plaster cast and glued together. A loose sorbo rubber lining has not been found to be necessary. For skin care elastic tubigrip seamed on one side can be used as a removable cover over the mandibular and occipital parts.
The anterior and posterior components of the mandibular-shoulder brace are then trial fitted on the patient and necessary minor modifications carried out. Fasteners (leather with Velcro) are fitted to the brace to hold the anterior and posterior elements together. If necessary, the mandibular and occipital parts can be connected by leather straps for extra support.
Finally, in order to strengthen the attachments of the chin and occipital pieces to the shoulder part of the brace, two extra vertical strips of 3mm Plexidur are glued in position.
A completed mandibular-shoulder brace should appear as in Fig. 4 .
Effectiveness of the mandibular-shoulder brace
The effectiveness of the mandibular-shoulder brace was assessed by fitting one to a 22 year old volunteer. X-rays of the cervical spine were taken in flexion and extension, before and after fitting the brace. The tube-film distance was 2.75m, to minimize distortion (Johnson et al, 1977).
Lines were drawn on the X-rays through corresponding points on each vertebra and the maximum range of motion at each level measured. The results are shown in Table 1 . A negative sign indicates a local reversal of tl.e general movement. During attempted extension of the neck, whilst wearing the brace, slight flexion occured at the C1-2, C2-3 and C3-4 levels. During attempted flexion of the neck, slight extension occurred at these levels.
Measurements of lateral flexion and rotation were not made because of the possible danger of excessive irradiation for the young volunteer.
Patient series
Up to now the halo-shoulder brace has been used on 12 patients, 9 of whom have subsequently required further support in a mandibular-shoulder brace; 1 patient needed support only in a mandibular-shoulder brace.
The details of these patients are shown in Table 2.
Discussion
The halo with a prefabricated plastic body vest has been shown to be a most effective manner of controlling the unstable cervical spine (Johnson et al, 1977).
The halo-thoracic brace (a halo connected to a prefabricated body vest) has proved successful in the treatment of fractures of the odontoid process (Schweigel, 1979).
However, because of asymmetry, a tender bony or cutaneous swelling or tender skin, difficulties often arise in fitting a mass-produced brace and so we developed a carefully moulded made-to-measure halo-shoulder brace and also a mandibular-shoulder brace.
We appreciate that we have only studied the range of movement in one volunteer, but by comparison with the restriction of movement obtained by the Philadelphia collar, the four-poster brace, the cervico-thoracic brace, the Somi brace and the polyethylene Camp plastic collar as described by Johnson et al (1977) and Fisher et al (1977), it would appear that the mandibular-shoulder brace effectively stabilizes the cervical spine.
Postoperative stabilization by one or a combination of these orthoses has so far proved satisfactory in the 13 patients described. Furthermore the braces are comfortable as well as being simple to remove and refit. In the case of the halo-shoulder brace only two buckles on the shoulder and 4 Allen screws to connect the rods on the halo are involved. In the case of the mandibular-shoulder brace 2 Velcro fasteners are used on the shoulder combined if necessary with 2 leather straps to connect the mandibular and occipital parts for extra support. It is worth mentioning that some of the patients initially preferred to sleep in skull traction until they became used to wearing the halo-shoulder brace 24 hours per day and some of the patients wore their halo-shoulder brace rather longer than expected as they took some time getting used to the transition from the halo-shoulder brace and its associated free movement of the lower jaw to the somewhat more restrictive mandibular-shoulder brace.
Regarding the manufacture of the braces the important substance is the 3mm orthopaedic Plexidur, which during the past few years has been developed into an exceptionally strong material. So far none of the orthoses have broken. The material is easy to mould and any minor corrections are simple to carry out with the aid of the heat gun, but these are seldom necessary when a good plaster cast is first made. The material is easy to clean and if necessary the patients can shower or wash their hair with the brace in place. Furthermore, the material is light and even with a halo and connecting rods the complete brace only weighs approximately 1,200 grammes.
The mandibular-shoulder brace only weighs approximately 360 grammes, is comfortable and well tolerated by the patient after removal of the halo-shoulder brace. Furthermore, this type of brace can be used on patients who for other reasons require a neck support, but who cannot tolerate a normal ready-made collar.
Acknowledgements
I wish to thank Mr. W. W. Fidler F.R.C.S. for his help and advice in the preparation of this article about patients under his care and also to thank Mr. D. van Doleweerd for the illustrations.
Further Reading
De Wald, R. L. (1975). Halo traction systems. In
Atlas of Orthotics, 407-417, The C. V. Mosby Co.,
St. Louis, U.S.A. Spinal Orthotics. New York University Post-Graduate
School, Prosthetics and Orthotics, 1975 (Course Manual).
References:
Fisher, S. V. (1977). Cervical orthoses, effect on cervical spine motion: Roentgenographic and goniometnc method of study. Arch. Phys. Med. Rehab., 58,109-115.
Johnson, R. M. et al (1977). Cervical orthoses. J. Bone Jt. Surg., 59A:3,332-339.
Schweigel, J. F. (1979). Halo-thoracic brace management of odontoid fractures. Spine 4:3,192-194.
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