Abstract:
In this article we describe how an 8-year-old girl having difficulty in mouth opening (1mm maximum opening) for 5 years was managed for full mouth opening in Kauvery hospital.
Presentation:
This 8 year old girl was self referred our oral and Maxillofacial unit with no mouth opening resulting in no ability to chew or eat food and difficulty in speaking. The child was hailing from Tirunelveli and approached many centers there for management. As the anesthesia was risky (chances of aspiration) and young age made the surgical procedure difficult in small centers without having enough infrastructure.
Suspected cause:
The parents had reported a history of chronic ear infection, for which the child had undergone a prior surgery. No clear cut other cause was derived including possible injury to TMJ condyle from any fall in childhood. If left untreated, it can progress to severe restriction in facial growth, especially the mandible, a compromised airway with sleep disordered breathing and psychological disability.
Clinically she had developed temporomandibular joint ankylosis, wherein the mandibular condyle fuses with the glenoid fossa at the cranial base. This prevents the lower jaw from opening, as the bony fusion prevents any hinge or articular movements of the joint. If left untreated, it can progress to severe restriction in facial growth, especially the mandible, a compromised airway with sleep disordered breathing and psychological disability.
Investigations:
A CT scan revealed complete fusion of the temporomandibular joint on the right side. The DICOM data from the CT scan was used to create a Sterolithographic model, which is an anatomical replica of the child’s skull and facial bones. This helped the surgeon plan the approach to the fused joint and also anticipate the difficulties in the resection of the joint.
Surgical Procedure:
The patient was taken up for the procedure and intubated with a fibre-optic bronchoscopy technique, which required the efficiency of a trained anaesthetist to maneuver the tube into the trachea through guided video scope, due to the lack of mouth opening.
While several techniques have been described for the treatment of the condition, adequate excision of the ankylotic mass and placement of an interpositional material remains the key step in surgical management. This was carried out with a pre-auricular approach to the joint, involving careful dissection to preserve the facial nerve branches. On reaching the joint space, the ankylotic mass was resected in layers in order to prevent hemorrhage from the arteries in the vicinity and ensure complete removal. The coronoid process was removed bilaterally, to aid in mouth opening. Following resection, the mouth opening was found to be around 35-40 mm. The ramus-condylar unit on the right side was then reconstructed with a costo-chondral graft, which is the preferred choice of material in children due to its growth potential. The graft is positioned and fixed with titanium plates & screws such that the bony part of the rib graft replaces the ramus of the mandible, and the cartilaginous portion creates the condylar segment.
The child was successfully extubated under direct vision of the vocal cords post-surgery due to the mouth opening achieved following resection and reconstruction of the ankylosed joint.
Dr. Manikandan Ramanathan
Consultant Maxillofacial Surgeon
Kauvery Hospital Chennai