The sternoclavicular joint (SCJ) has similar anatomical and physical characteristics to the temporomandibular joint (TMJ). The purpose of this article is to introduce a modified technique for the pedicled SCJ and the expanded indications for its use. During the period June 2011 to June 2014, six TMJs were reconstructed using the superior half of the SCJ pedicled with the sternocleidomastoid muscle. The inclusion criteria were (1) poor vascularization jeopardizing a non-vascularized TMJ replacement, and/or (2) a large defect of both bone and soft tissue. The average follow-up period was 14.8 months (range 7–39 months). Fracture of the clavicle occurred in one patient (16.7%). No recurrence, graft resorption, or secondary deformity was found. Reconstruction of the TMJ using the superior half of the SCJ pedicled with the clavicle head of the sternocleidomastoid muscle and sternocleidomastoid branch of the superior thyroid artery benefited patients who had a poor blood supply and a medullary condition or who had a defect in both the condyle and surrounding soft tissue.
The condyle of the temporomandibular joint (TMJ) plays an important role in facial aesthetics and jaw function. Loss of the condyle may sometimes occur due to developmental disorders, trauma, ankylosis, osteoarthritis, idiopathic resorption, a benign or malignant pathology, or infection. Multiple autogenous tissues and alloplastic materials have been used to reconstruct the condyle. However, due to the high cost of alloplastic materials, most countries prefer autogenous grafts, such as the coronoid process, border of the ramus, costochondral graft (CCG), sternoclavicular joint (SCJ), iliac crest, vascularized metatarsophalangeal joint, and fibular flap.
The SCJ has similar anatomical and physical characteristics to the TMJ, and the absence of the SCJ results in no obvious functional or aesthetic problems. Since the study by Wolford et al. in 1994, recent reports have stated a preference for the free superior half of the SCJ for reconstruction of the TMJ. The key point of this technique is to place the graft on the posterior border of the mandible such that the graft can be vascularized by direct exposure of the graft marrow to adjacent soft tissue. However, for some patients with poor vascularization jeopardizing a non-vascularized TMJ replacement, the free SCJ graft may be absorbed due to ischaemia. Further, some malignant tumours may result in a defect of both the condyle and soft tissue, and the free SCJ graft may be insufficient to pack the defect. Although Siemssen and Korula et al. described a method for replacement of the TMJ with a muscle-pedicled SCJ, this technique was too complex and invasive to become widely accepted. In addition, all reports on the SCJ were for the indication of ankylosis.
Is there a more simplified technique for the muscle-pedicled SCJ? Could it be tried in other conditions where there is poor vascularization or a large resection area? To answer these questions, six TMJ reconstructions using the superior half of the SCJ pedicled with the sternocleidomastoid muscle were attempted between June 2011 and June 2014. The purpose of this article is to introduce the indications for the use of the pedicled SCJ and the modified technique, and to report the preliminary effects.
Materials and methods
The study protocol was approved by and was performed in accordance with the recommendations of the human research committee of the study institution. All patients gave written consent prior to scanning and surgical procedures.
The inclusion criteria were (1) poor vascularization jeopardizing a non-vascularized TMJ replacement, and/or (2) a large defect of both bone and soft tissue. The prospective clinical study included six patients (six TMJs) from June 2011 to June 2014. The male to female gender ratio was 1:5 (female preponderance). The age range was 31 to 65 years, with a mean age of 51.3 years. All defects were on the right side. The preoperative diagnosis was neoplasm in four cases, osteonecrosis after septic arthritis in one case, and recurrent ankylosis after CCG reconstruction in one case ( Table 1 ). Two patients suffered from malignant tumours, and a large resection was performed. Two patients with synovial chondromatosis had a destroyed condyle that could not be separated from the calcified mass and needed a condylectomy with resection of the mass.
|Patient no.||Gender||Age (years)||Side||Aetiology||Indication for pedicled SCJ||Symptoms|
|1||F||47||R||Metastatic tumour from breast||Defect both of condyle and soft tissue||Swelling|
|2||M||65||R||Synovial chondromatosis||Defect of condyle; age||Pain, limitation of mouth opening|
|3||F||56||R||Synovial chondrosarcoma||Defect both of condyle and soft tissue; age||Pain, swelling, noise|
|4||F||55||R||Osteonecrosis after septic arthritis||Infection; age||Pain, limitation of mouth opening|
|5||F||54||R||Synovial chondromatosis||Defect of condyle; age||Pain, swelling, noise|
|6||F||31||R||Recurrent ankylosis after CCG reconstruction||Defect both of condyle and soft tissue; scar of soft tissue||Asymmetry, swelling, limitation of mouth opening, malocclusion|
Modified surgical technique
The surgical intervention was performed under general anaesthesia. A temporal and pre-auricular approach was used to explore the TMJ and to remove the condyle with or without the surrounding soft tissue. A pedicled deep temporal fascial fat flap (DTFFF) of 5–6 mm in thickness was prepared to separate the skull base and the SCJ. A submandibular approach was used to gain access to the ramus of the mandible and to shave the posterior border of the ramus. The mandible was secured with maxillomandibular fixation, except in the patient with recurrent ankylosis whose mandible was stabilized with an occlusal relocation splint.
The ipsilateral SCJ was harvested. An incision was made 1 to 2 cm above the clavicle. The sternocleidomastoid muscle was exposed. The periosteum and the clavicle head of the muscle attachment of the superior and medial aspect of the clavicle were protected ( Fig. 1 ). The ligamentous attachments of the articular disc of the SCJ were maintained with the graft. The technique used to cut down the superior half of the clavicle and SCJ with half disc was identical to the Wolford technique. The remaining half of the SCJ and the sternal head of the sternocleidomastoid muscle remained in situ. The sternocleidomastoid muscle was released until the folded muscle was long enough for the SCJ to reach the glenoid fossa. In this way, the SCJ graft pedicled with the clavicle head of the sternocleidomastoid muscle was obtained. The remaining clavicle was fixed with a thick titanium plate to avoid fracture.
The SCJ graft was transferred to the TMJ region through the subcutaneous tissue of the neck. The SCJ graft was then fixed to the posterior border of the ramus with two titanium plates, providing the best fit in the glenoid fossa ( Fig. 2 ). The disc of the graft was sutured to the lateral pterygoid muscle or DTFFF. Finally the surgical areas were irrigated and closed. Elastic maxillomandibular fixation was placed for 1 month in order to make the SCJ graft stable. At 1 month post-surgery, aggressive physiotherapy could be started.
Criteria for success
Based on the study of Wolford et al., our criteria for success included the following: (1) no secondary deformity, (2) stable functional occlusion, (3) adequate mobility of the jaws (≥30 mm) or significant improvement, (4) no resorption of the SCJ graft on computed tomography (CT) scan, and (5) no recurrence.
Six patients with six TMJs reconstructed with an SCJ graft pedicled with the sternocleidomastoid muscle were followed-up for an average of 14.8 months (range 7–39 months). Any swelling and noise disappeared. Pain decreased significantly or was eliminated ( P = 0.028) ( Table 2 ). The first five cases had stable occlusion without any change compared to the preoperative occlusion. Mouth opening in all of these cases was more than 30 mm. The remaining case was the patient with recurrent ankylosis. This patient’s mandible was moved forward and the deep overbite was corrected after reconstruction of the condyle. Her mouth opening improved from 0 mm to 25 mm.
|Patient no.||Follow-up period (months)||Pain, VAS||Occlusion||Mouth opening (mm)||Height of the ramus (mm)||Recurrence|
|Pre-||Post-||Pre-||Post-||Pre-||Post-||Pre-||Post- (1 week)||Post- (update)|
Using coronal CT scans, the height of the ramus was measured before the operation, immediately after the operation, and during the follow-up period. In the first five cases, there was no significant difference among the three sets of scans ( Table 2 ). In the patient with recurrent ankylosis, the height of the ramus immediately after the operation was 4.65 mm higher than that before the operation because of the mandible having moved forward.
There were no severe complications, such as facial paralysis, infection, resorption of the SCJ graft, or loosening of the screws. Fracture of the clavicle occurred in one patient (16.7%). No recurrence was found during the follow-up period.
A 54-year-old woman presented with complaints of pre-auricular swelling and pain in the right side of 1-year duration. The pain was constant at 5 on the visual analogue scale (VAS, 0–10) and was aggravated by joint palpation. Physical examination showed an obvious diffuse swelling of the right pre-auricular region. There was a noise in her right TMJ. Maximal mouth opening was 38 mm with deviation to the right side. Her occlusion was stable with some missing teeth. CT showed a calcified mass around the condyle, and the bone cortex was destroyed ( Fig. 3 A and B). Magnetic resonance imaging (MRI) revealed a heterogeneous signal mass in the superior and inferior compartments, without perforation of the disc ( Fig. 4 ).