**5.1 Clinical data**

6 Modern Arthroscopy



Most scientists regard osteoarthritis as an inflammatory process, being most frequent TMJ disorder, characterised with proliferative changes in the synovia and primary degeneration of the cartilage and surrounding tissues with destruction of the bone structures. (Holmlund & Axelsson, 1996; Emshoff , 2005). It is found that 28% of the adult population have signs of temporomandibular joint disorder. In systemic diseases (rheumatoid arthritis, psoriasis etc.) involvement of TMJ occurs (Voog et al., 2003b; 2004). Main aetiological factors of TMJ disorders are as follows: systemic diseases ( rheumatoid arthritis, psoriasis, pseudogout, ankylosing spondylitis etc.), secondary inflammatory component from the neighbouring regions (otitis, maxillary sinusitis, tonsillitis ), trauma (chronical), prevalence of dental arch defects e.g. missing of molar teeth, (Tallents et al. 2002), malocclusion, endocrinological disturbances, odontogenic infections (third molars). Presence of specific bacterial species as *Staphylococcus aureus, Streptococcus mitis, Mycoplasma fermentas, Actinobacillus actinomycetemcomitans (Aa)* in the synovial fluid have been found (Kim et al., 2003). Serum antibodies against *Chlamydia spp.* in patients with monoarthritis of the TMJ have been occurred. An association may exist between the presence of *Chlamydia trachomatis* and TMJ

Knowledge about the pathogenesis on a molecular level of disorders of the TMJ has been improved in recent years giving a possibility to use these data for the evidence based treatment. Inflammation mainly affects the posterior disc attachement (Holmlund & Axelsson, 1996; Leibur et al., 2010). Several inflammatory mediators play an important role in the pathogenesis of TMJ diseases as tumor necrosis factor α (TNFα), interleukin-1β (IL-1β), prostaglandin E2 (PGE2), leukotrien B4 (LkB4 ), matrix metalloproteinases (MMPs), serotonin- 5 hydroxytryptamine (5-HT), (Alstergren et al., 1999; Voog et al., 2003b). MMPs are responsible for the metabolism of extracellular matrix, being an early marker to determine TMJ arthritis. High level of MMP-3 has been determined in the synovial fluid in TMJ osteoarthritis patients (Kamada et al., 2000). Serotonin, mediator of pain and inflammation, is produced in the enterocromaffin cells of the gastrointestinal mucosa and absorbed by platelets. It is produced also in the synovial membrane and is present in the synovial fluid and in blood in case of rheumatoid arthritis and is involved in the mediation of TMJ pain in systemic inflammatory joint diseases (Alstergren & Kopp, 1997; Voog et al., 2000). It plays a role also in bone metabolism (Warden & Haney, 2008). Tissue response in case of inflammation is as follows:

**4. Aetiology and pathogenesis of temporomandibular disorders** 

**3. Classification of temporomandibular joint disorders:** 





disease (Paegle et al., 2004).

**4.2 Pathogenesis** 

hyperplasia

**4.1 Aetiology** 

The most frequent complaint is pain and a decrease in the maximal interincisal opening (MIO), which normal values are between 35 - 50 mm (Fig. 3).

The following symptoms as pain (at rest, during maximum mouth opening and upon chewing), tenderness to digital palpation of the joint, sounds (clicking, crepitation), restricted mandibular mobility e.g*.* difficulty in opening the mouth, intermittent lock, closed lock, stiffness in the morning are observed. The stages of disease are usually classified according to Wilkes (1989; Table 1) by reviewing the case histories, clinical data, radiological records (computerized tomography images, magnetic resonance images, ortopantomography and/or plain radiographs by Schüller, Parma).



c. Pathoanatomy: Increase in severity over intermediate stage; hard tissue degenerative remodelling of both bearing surfaces (osteophyts), multiple adhesions in anterior and posterior recesses; no perforation of disk or attachments

Temporomandibular Joint Arthroscopy 9

Radiological changes of the TMJ are evaluated by orthopantomography (OPTG), computed tomography (CT), magnet resonance imaging (MRI) (Ohnuki et al. 2003; Voog et al., 2003b,

OPTG is mainly used to demonstrate the structural bone changes in the TMJ and it has the advantage of being easily available but gaves limited information about the above mentioned joint being an alternative method to other radiological methods. To obtain a more detailed anatomic picture, CT or MRI are recommended. By evaluating the OPTGs the following radiographic signs of bone structural changes can be achieved such as presence of erosions, flattening and osteophytes of the condyle as well as temporal bone (Rohlin et al., 1986). Erosion in condyles in the radiographs is scored according to Helenius et al. (2004) as follows: score 1 - very slight erosion; score 2 - erosion on top of the condyle; score 3 - half of condyle is eroded; score 4 - condyle totally eroded. The first report of TMJ CT was published by Suarez et al. (1980) and this method is superior to plain transcranial or transmaxillary imaging for detecting bone changes. CT allows detailed three-dimensional examination of the TMJ and it is capable to detect even small bone changes not demonstrable by conventional tomographic procedures (Raustia et al., 1985; Larheim & Kolbensvedt, 1990). The CT sections are evaluated for presence of radiographic signs of bone changes within three regions (lateral, central and medial) of the mandibular and temporal part (eminence) of the TMJ. The recording of the signs is made in the axial, coronal and sagittal views (Emshoff et al., 2003; Voog et al., 2003). The changes are defined as follows: erosion - a local area with decreased density of the cortical joint surface including or not including adjacent subcortical bone (Fig.4), sclerosis - a local area with increased density of the cortical bony joint surface that may extend into the subcortical bone (Fig. 5), subchondral pseudocyst - a well defined, local area of bone rarefication underneath an intact cortical outlining of the joint surface, flattening - a flat bony contour deviating from the convex form (Fig. 6), osteophyte - a marginal bony outgrowth (Fig. 6). The grade of the total changes of the TMJ can be evaluated according to the scoring system developed by Rohlin & Petersson (1989) as

Fig. 4. Osteoarthritis of the TMJ. Signs of erosions on the surfaces of the condyles in a coronal view of the CT. An irregular outline is revealed on the condyles. The bone structure

2004; Whyte et al., 2006) as well as ultrasonography (C.A. Landes et al., 2007).

**5.2 Radiographic investigations** 

well.

of the both glenoid fossa is normal.

#### V. Late stage


Table 1. Classification for internal derangement of the TMJ by Wilkes (1989).

Fig. 3. Maximal interincisal opening (MIO) is 13 mm.

Symptom related factors obtained by questionnaire, the scores pre- and posttreatment maximal interincisal opening (MIO) and visual analogue scale (VAS) for pain are to be documentated and compared. Joint pain is assessed with 100 mm visual analogue scale with end points marked "no pain" and "worst pain ever experienced". The absence of pain is scored as 0. If pain is present the patient is asked to select marked field from 1mm to 100 mm.

It is known that inflammation often is accompanied by pain. Evaluation and estimation of the impact of pain is a complicated matter, since pain has many different ways to interfere with everyday life. The impact of pain on the health status and quality of life in patients with chronic inflammatory joint diseases has been recognized, but there is a lack of knowledge about the specific impact of TMJ pain on daily activities in patients with clinical involvement of the TMJ. A scale for measuring the activity of daily living (ADL), (List & Helkimo, 1995) is a useful tool for assessment of the restriction of activities of patients with TMJ disorders in their everyday life (Voog et al., 2003a; Kaselo et al., 2007; Jagur et al., 2011).

a. Clinical: Characterized by crepitus; variable and episodic pain; chronic restriction of

b. Radiologic: Disc or attachment perforation, filling defects, gross anatomic deformity of disc and hard tissues, positive tomograms with essentially degenerative arthritic

c. Pathoanatomy: Degenerative changes of disc and hard tissues; perforation of posterior attachement; multiple adhesions, osteophyts, flattening of condyle and

Symptom related factors obtained by questionnaire, the scores pre- and posttreatment maximal interincisal opening (MIO) and visual analogue scale (VAS) for pain are to be documentated and compared. Joint pain is assessed with 100 mm visual analogue scale with end points marked "no pain" and "worst pain ever experienced". The absence of pain is scored as 0. If pain is present the patient is asked to select marked field from 1mm to 100

It is known that inflammation often is accompanied by pain. Evaluation and estimation of the impact of pain is a complicated matter, since pain has many different ways to interfere with everyday life. The impact of pain on the health status and quality of life in patients with chronic inflammatory joint diseases has been recognized, but there is a lack of knowledge about the specific impact of TMJ pain on daily activities in patients with clinical involvement of the TMJ. A scale for measuring the activity of daily living (ADL), (List & Helkimo, 1995) is a useful tool for assessment of the restriction of activities of patients with TMJ disorders in their everyday life (Voog et al., 2003a; Kaselo et al., 2007; Jagur et al., 2011).

Table 1. Classification for internal derangement of the TMJ by Wilkes (1989).

V. Late stage

changes

mm.

motion and difficulty with function

eminence, subcortical cyst formation

Fig. 3. Maximal interincisal opening (MIO) is 13 mm.

#### **5.2 Radiographic investigations**

Radiological changes of the TMJ are evaluated by orthopantomography (OPTG), computed tomography (CT), magnet resonance imaging (MRI) (Ohnuki et al. 2003; Voog et al., 2003b, 2004; Whyte et al., 2006) as well as ultrasonography (C.A. Landes et al., 2007).

OPTG is mainly used to demonstrate the structural bone changes in the TMJ and it has the advantage of being easily available but gaves limited information about the above mentioned joint being an alternative method to other radiological methods. To obtain a more detailed anatomic picture, CT or MRI are recommended. By evaluating the OPTGs the following radiographic signs of bone structural changes can be achieved such as presence of erosions, flattening and osteophytes of the condyle as well as temporal bone (Rohlin et al., 1986). Erosion in condyles in the radiographs is scored according to Helenius et al. (2004) as follows: score 1 - very slight erosion; score 2 - erosion on top of the condyle; score 3 - half of condyle is eroded; score 4 - condyle totally eroded. The first report of TMJ CT was published by Suarez et al. (1980) and this method is superior to plain transcranial or transmaxillary imaging for detecting bone changes. CT allows detailed three-dimensional examination of the TMJ and it is capable to detect even small bone changes not demonstrable by conventional tomographic procedures (Raustia et al., 1985; Larheim & Kolbensvedt, 1990). The CT sections are evaluated for presence of radiographic signs of bone changes within three regions (lateral, central and medial) of the mandibular and temporal part (eminence) of the TMJ. The recording of the signs is made in the axial, coronal and sagittal views (Emshoff et al., 2003; Voog et al., 2003). The changes are defined as follows: erosion - a local area with decreased density of the cortical joint surface including or not including adjacent subcortical bone (Fig.4), sclerosis - a local area with increased density of the cortical bony joint surface that may extend into the subcortical bone (Fig. 5), subchondral pseudocyst - a well defined, local area of bone rarefication underneath an intact cortical outlining of the joint surface, flattening - a flat bony contour deviating from the convex form (Fig. 6), osteophyte - a marginal bony outgrowth (Fig. 6). The grade of the total changes of the TMJ can be evaluated according to the scoring system developed by Rohlin & Petersson (1989) as well.

Fig. 4. Osteoarthritis of the TMJ. Signs of erosions on the surfaces of the condyles in a coronal view of the CT. An irregular outline is revealed on the condyles. The bone structure of the both glenoid fossa is normal.

Temporomandibular Joint Arthroscopy 11

MRI has a diagnostic value for internal derangements of the TMJ and rapidly surpassing CT as the imaging method of choice. MRI can detect not only TMJ soft tissue abnormalities like disc displacements, pathology of synovial membrane or capsule, pathology in the posterior attachement but also hard tissue morphologic changes can be demonstrated with MRI (Lieberman et al., 1996; Larheim et al., 1999). Sections in the oblique sagittal plane (i.e. perpendicular to the horizontal long axis of the mandibular condyle) and oblique coronal plane (i.e*.* parallel with the long axis of the condyle), and bilateral temporomandibular base

The biting device (MEDRAD; Pittsburg) which enables dynamic imaging can be used as bite blocks during the open jaw phase of the imaging procedure (Gaggl et al.,1999). Dynamic magnetic resonance imaging is a recent method that investigate directly in vivo articular function and shows much promise as a noninvasive method of the disc function, however this limitation should diminish with continuing technological advances in the imaging field. Ultrasonography has been a helpful diagnostic approach for patients with TMJ disorders, having a possibility to diagnose with considerable reliability when compared with MRI and being a sensitive tool for assessing joint function (C. Landes et al*.*, 2000; C.A. Landes et al.,

Fig. 7. An osteophyte in the medial part of the right mandibular condyle in a sagittal view of

the CT., cortical destruction of the glenoid fossa surface.

surface coils are used (Larheim et al., 2001) for obtaining the images (Fig. 8).

2006).

Fig. 5. Axial view of the CT. Sign of sclerosis in the medial and central parts of the right condyle of the mandible ( arrow) . Reduced space is seen.

Fig. 6. Sagittal view of the CT from the left temporomandibular joint. Sign of flattening of the condyle.

Fig. 5. Axial view of the CT. Sign of sclerosis in the medial and central parts of the right

Fig. 6. Sagittal view of the CT from the left temporomandibular joint. Sign of flattening of

condyle of the mandible ( arrow) . Reduced space is seen.

the condyle.

MRI has a diagnostic value for internal derangements of the TMJ and rapidly surpassing CT as the imaging method of choice. MRI can detect not only TMJ soft tissue abnormalities like disc displacements, pathology of synovial membrane or capsule, pathology in the posterior attachement but also hard tissue morphologic changes can be demonstrated with MRI (Lieberman et al., 1996; Larheim et al., 1999). Sections in the oblique sagittal plane (i.e. perpendicular to the horizontal long axis of the mandibular condyle) and oblique coronal plane (i.e*.* parallel with the long axis of the condyle), and bilateral temporomandibular base surface coils are used (Larheim et al., 2001) for obtaining the images (Fig. 8).

The biting device (MEDRAD; Pittsburg) which enables dynamic imaging can be used as bite blocks during the open jaw phase of the imaging procedure (Gaggl et al.,1999). Dynamic magnetic resonance imaging is a recent method that investigate directly in vivo articular function and shows much promise as a noninvasive method of the disc function, however this limitation should diminish with continuing technological advances in the imaging field. Ultrasonography has been a helpful diagnostic approach for patients with TMJ disorders, having a possibility to diagnose with considerable reliability when compared with MRI and being a sensitive tool for assessing joint function (C. Landes et al*.*, 2000; C.A. Landes et al., 2006).

Fig. 7. An osteophyte in the medial part of the right mandibular condyle in a sagittal view of the CT., cortical destruction of the glenoid fossa surface.

Temporomandibular Joint Arthroscopy 13

preauricular concavity is formed in the skin, marking a point for the injection. Usually arthroscope KARL STORZ GmbH & Co.KG is used. Although various arthroscopic approaches to the TMJ have been described, the one most commonly used is the posterolateral approach to the upper joint space. After the condylar head of the TMJ has been determined , a marking line and puncture points are made on the skin surface (Fig. 9).

Fig. 9. A marking line and the puncture points on the skin surface for TMJ arthroscopy

The puncture site is located by manipulating the mandible anterio-inferiorly. For distension of the superior compartement and in order to avoid iatrogenic damage to the cartilaginous surfaces during introduction of the trocar, 1% lidocain solution 2,0 mL is inserted. The needle is aimed in a medial and slightly anteriosuperior direction until the contact with the glenoid fossa is achieved. The posterior recess of the superior joint space is reached when there is a backflow into the syringe of the solution injected into the joint space (Fig.10).

Fig. 10. Distension of the superior compartment of the right temporomandibular joint with

2% lidocaine solution.

Fig. 8. Sagittal view of the MRI in a patient with internal derangement of the left TMJ. Anterior disc displacement (arrow), destruction of the disc. Changes of bone structures, effusion in the anterior recess.
