1/157. Electromyographic activity of the jaw-closing muscles before and after unilateral coronoidectomy performed on a patient with coronoid hyperplasia: a case study. There have been few reports analyzing the activity of the jaw-closing muscles after coronoidectomy performed on a patient with coronoid hyperplasia. This paper presents a case study using electromyograms (EMGs) to evaluate the effects of unilateral coronoidectomy on the activity of masseter and temporal muscles. The patient was a 25-year-old male whose maximal range of jaw opening was 24 mm. After coronoidectomy of the left region, the range improved to 43 mm. EMGs were recorded in the center of the masseter muscles and the anterior part of the temporal muscles during gum chewing. Preoperatively, no abnormal EMG activity was observed. Eight months after surgery, increase in the ratio of the bilateral temporal muscle activity and a decrease in the ratio of the right masseter muscle activity were observed, and the proportion of activity of jaw closing muscles was out of the normal range. Eighteen months after surgery, there was slight return to the preoperative EMG activity. It was concluded that unilateral coronoidectomy could result in EMG changes of masseter and temporal muscles with a gradual return. ( info) |
2/157. Moebius syndrome: the new finding of hypertrophy of the coronoid process. The first detailed description of congenital facial paralysis was reported by Moebius in 1888. It is characterized by either unilateral or bilateral paralysis of the facial muscles and an associated abducens palsy. The present report is of two patients with Moebius syndrome, who were also diagnosed with trismus at birth. Each patient also demonstrated bilateral hypertrophy of the coronoid process of the mandible. In effect, the zygoma obstructed the excursion of the mandible because of a "coronoid block." A three-dimensional computed tomography scan demonstrated normal temporomandibular joints but bilateral hypertrophy of the coronoid processes and micrognathia. Both patients demonstrated less than 10 mm of oral excursion. Bilateral coronoidectomies were performed through an intraoral approach. The oral excursions after surgery increased to at least 20 mm. In each of these patients, the coronoid process was enlarged relative to the zygoma, which was of normal size and configuration. The trismus was associated with blocking of the coronoid by the anterior zygoma, preventing open or full excursion of the hypoplastic mandibles. Moebius syndrome can have a variable presentation at birth. In two patients, the authors describe a new finding of hypertrophy of the coronoid process and trismus secondary to obstruction of the coronoid by the hypertrophic zygomas during oral excursions. Each patient is described, and a review of the literature is discussed. ( info) |
| Tracheal intubation of a child with trismus pseudocamptodactyly (Hecht) syndrome is described. This disorder is characterized by progressive trismus and the need for repeated surgeries. Children intubated orally on a prior occasion may require an alternative approach subsequently due to progressive inability to open the mouth. An antegrade fiberoptic-guided nasotracheal technique initially was chosen due to extremely limited mouth opening. After this approach was unsuccessful, a retrograde guidewire-assisted fiberoptic intubation was performed. The manifestations of Hecht syndrome, as well as both techniques for tracheal intubation employed, are reviewed. ( info) |
4/157. Anaesthetic management of two paediatric patients with Hecht-Beals syndrome. We undertook the anaesthetic management of two children with Hecht-Beals syndrome for orthopaedic surgery under general anaesthesia. Both patients had arachnodactyly, kyphoscoliosis, and multiple congenital joint contractures, but limited mandible excursion was not obvious preoperatively in either, although mental retardation made it difficult for them to cooperate with mouth examination. They had no apparent difficulties with their mouths in daily activities. The anaesthesia records of one patient showed that intubation had been difficult in an earlier procedure. The other patient also had a history of difficult intubation, with slight tearing of the corners of her mouth during an intubation procedure. During slow induction of general anaesthesia with sevoflurane, face mask ventilation was easily performed. We attempted to visualize the larynx under anaesthesia with muscle relaxation, but we were unsuccessful because of the limited mouth opening. After several trials, blind oral intubations were fortunately successful in both patients. There were no postoperative problems with the airway. ( info) |
5/157. An unusual cause of trismus. This paper reports a case of limited mandibular movement caused by the rare condition of bilateral coronoid hyperplasia. Dental surgeons should be aware of the possibility of this condition when encountering patients with movement problems in the mandible. ( info) |
6/157. Recurrent steroid-responsive trismus and painful ophthalmoplegia. A 63-year-old woman experienced two episodes of trismus and painful ophthalmoplegia at an interval of six years. She suffered left visual loss, and enhanced CT scan and MR imaging revealed heterogeneous enlargement of the left extraocular muscles extending to the orbital apex. In addition, the left pterygopalatine fossa was filled with a mass isointense with muscle without evidence of surrounding tissue invasion; 67Ga scintigraphy showed high uptake in this lesion. Steroid administration dramatically resolved the trismus, and the mass in the orbit and extraorbit vanished completely. orbital pseudotumor is characterized by self-limited, relapsing, steroid-responsive painful ophthalmoplegia, and this case could be a variant of this entity with inflammation extending into the extraorbital area. ( info) |
7/157. Difficult tracheal intubation following midface distraction surgery. A case of difficult intubation in a patient with Apert syndrome, who had recently undergone bilateral internal midface distraction, is described. The 14-year-old boy had no antecedent history of such difficulty, despite numerous previous anaesthetics. We suggest that trismus due to temporalis muscle fibrosis, and the altered relationships of the maxilla and mandible following midface advancement, were causal. ( info) |
8/157. Congenital trismus secondary to masseteric fibrous bands: endoscopically assisted exploration. The authors present an 18-month-old female infant with congenital trismus. Computed tomography and magnetic resonance imaging were not helpful in determining the cause. A surgical endoscope was used to explore her temporomandibular joints and temporal fossae, thus avoiding the morbidity of a bicoronal incision. The cause was bilateral fibrous bands on the anterior border of the masseter muscles. Incision of these fibrous bands led to relief of the trismus. This finding is consistent with a previously described variant of the Hect-Beals-Wilson trismus-pseudocamptodactyly syndrome. This patient, however, had no evidence of the autosomal dominant inheritance pattern nor did she exhibit pseudocamptodactyly, both of which are generally ascribed to this syndrome. Unfortunately the trismus recurred 3 months postoperatively. ( info) |
| Three cases of unusual trismus are reported, occurring in patients with lesions of the central nervous system. On the basis of the clinical and electromyographical findings and observation of the course of the trismus this is interpreted as a symptom of a lesion of the brain stem, causing a dis-synergism of the masticatory muscles. ( info) |
10/157. Trigeminal neurinoma presenting with trismus. We describe a patient with trigeminal neurinoma whose main presenting symptom was trismus. This has not previously been reported in the literature. We review the previously described symptoms and signs of trigeminal neurinoma. ( info) |