Intra-articular Injection of Medications in TMJ After Arthrocentsis

II. Introduction:

1. Background and rationale: Research question? In patients with anterior disc displacement with reduction, what is the therapeutic effect of intra-articular injection of hyaluronic acid and corticosteroids mixture after arthrocentesis versus hyaluronic acid and prp mixture after arthrocentesis in terms of jaw movement, pain relief, decreasing clicking and frequency of locking?

Statement of the problem:

Internal derangement and osteoarthritis are the most common degenerative temporomandibular joint diseases.

Hyaluronic acid and corticosteroids mixture have been proved in literature to represent a more effective method to preserve and treat joints (knee joints and temporomandibular joints)

Rationale for conducting the research:

The rationale of this procedure is to remove inflammatory mediators, reduce friction, stimulate the production of new synovial fluid, eliminate suction-cup effect.

The purpose of this study was to evaluate the hypothesis that TMJ injection of hyaluronic acid and corticosteroids mixture after arthrocentesis leads to better clinical outcomes in terms of reducing pain and improving function compared with injection of hyaluronic acid and prp mixture after arthrocentesis in patients with TMJ internal derangement and osteoarthritis Preliminary results of this clinical trial show that the injection of hyaluronic acid and corticosteroids mixture can significantly improve outcomes of pain and function compared with the standard treatment and encourage to pursue research on this topic.

Further studies with a longer follow-up time are needed to evaluate the clinical stability of the achieved improvement in pain and function.

For this reason, this protocol has been designed with the aim to investigate whether injection in the TMJ of hyaluronic acid and corticosteroids mixture after can achieve the same improvements of pain and function, compare this technique with hyaluronic acid and platelet rich plasma mixture injection.

Review of literature Anterior disc displacement with reduction of the temporomandibular joint (TMJ) is a prevalent condition characterized by the displacement of the articular disc during jaw movement, often leading to pain, clicking sounds, and restricted mouth opening. Traditional treatments include conservative approaches such as physical therapy, occlusal splints, and pharmacological interventions. However, for patients unresponsive to these methods, intra-articular injections of therapies like hyaluronic acid, corticosteroids mixture and hyaluronic acid, platelet-rich plasma (PRP)mixture have emerged as promising alternatives.

Arthrocentesis is the simplest intervention on the TMJ with the aim to decrease joint pain and improve the range of motion in patients not responding to initial conservative treatment.

Arthrocentesis consists of an intraarticular lavage using 2 needles placed in the upper joint space. It is a versatile technique which can be performed under local anesthesia in an outpatient setting as well Arthrocentesis has been demonstrated to be a very effective procedure with a high success rate and a favorable benefit-cost ratio.

In addition to arthrocentesis:

Hyaluronic acid and corticosteroids mixture injection Introduction: Temporomandibular joint disorders (TMDs) represent a diverse group of conditions affecting the TMJ, masticatory muscles, and associated structures. Intra-articular injections of therapeutic agents, particularly Hyaluronic Acid (HA) and Corticosteroids (CS), have been utilized to reduce inflammation and improve joint mobility. Recently, studies have explored the combined use of HA and CS, aiming to capitalize on the anti-inflammatory effects of CS and the viscoelastic, lubricating, and regenerative properties of HA.

1. Hyaluronic Acid in TMJ Disorders: HA is a natural component of synovial fluid and plays a critical role in joint lubrication and cartilage health. In a systematic review, intra-articular HA injections showed significant improvements in pain and jaw function in patients with TMDs HA promotes endogenous synthesis of proteoglycans, reduces cartilage degradation, and provides mechanical cushioning.
2. Corticosteroids in TMJ Disorders: CS are potent anti-inflammatory agents that reduce joint pain and inflammation by inhibiting cytokine production and leukocyte infiltration. intra-articular CS injections lead to short-term pain relief but could result in cartilage damage if overused. Side effects of repeated CS injections may include joint degeneration and reduced joint space.
3. Combined HA and CS Injections:

The combination aims to provide rapid pain relief (via CS) while enhancing joint lubrication and healing (via HA).

a randomized clinical trial comparing HA alone, CS alone, and a mixture of both. The HA+CS group showed faster pain relief and better functional recovery at early time points, although long-term outcomes were similar to HA alone.

Yilmaz : Found that the combined injection provided superior improvement in mouth opening and pain control compared to either agent alone.

HA+CS combination is effective in patients with internal derangement and osteoarthritis of the TMJ, especially when guided by ultrasound for accurate injection placement.

Hyaluronic acid and PRP mixture injection The synergistic effect of HA and PRP is hypothesized to enhance joint function and alleviate pain more effectively than either agent alone.

Clinical Evidence

Several studies have investigated the efficacy of HA and PRP combination therapy:

Synergistic Effect Study: A randomized controlled trial . demonstrated that patients receiving combined HA and PRP injections post-arthrocentesis experienced significant improvements in pain reduction and maximum mouth opening compared to those receiving either HA or PRP alone.

Comparative Study: evaluated the participation of HA with PRP in the treatment of TMJ disorders. Their study found that the combination therapy provided greater improvements in pain at mastication, masticatory efficiency, and functional limitation in mandibular movement over a 6-month follow-up period compared to HA alone.

Systematic Review: A systematic review indicated that while arthrocentesis alone effectively reduces pain and improves jaw function, additional injections of HA or PRP do not significantly enhance clinical outcomes. However, the combination of HA and PRP may offer synergistic benefits, though further high-quality studies are needed to confirm this.

Comparative Efficacy While both hyaluronic acid, corticosteroids mixture and hyaluronic acid, prp mixture injections have demonstrated efficacy in treating joint disorders, direct comparative studies in the context of TMJ anterior disc displacement with reduction are limited. The existing literature primarily focuses on individual therapies rather than head-to-head comparisons. Therefore, it is challenging to definitively conclude which treatment offers superior outcomes for TMJ disorders.

Explanation for choice of comparator

1. The choice of a hyaluronic acid (HA) and corticosteroids (CS) mixture injection in the treatment of anterior disc displacement with reduction of the temporomandibular joint (TMJ) is based on anti-inflammatory effects to manage symptoms and improve joint function. Here's a breakdown of the rationale:
2. Pathophysiology of Anterior disc displacement with reduction In Anterior disc displacement with reduction, the disc moves anteriorly during mouth closure and returns to its normal position during opening, often producing clicking sounds. Repetitive disc displacement can lead to synovial inflammation, joint effusion, and cartilage wear, which result in pain and functional limitation
3. Why Hyaluronic Acid? Lubrication: HA restores the viscosity of synovial fluid, reducing friction between joint surfaces. Shock Absorption: It protects joint structures during mandibular movements. Anti-inflammatory effects: HA can inhibit inflammatory mediators like IL-1 and prostaglandins. Cartilage Protection: It promotes chondrocyte activity and slows down degenerative changes.
4. Why Corticosteroids? Potent anti-inflammatory: CS reduce synovial inflammation quickly by suppressing cytokines and inflammatory cell activity. Pain relief: CS can rapidly decrease pain by reducing joint swelling and pressure. Short-term efficacy: Especially useful in acute or highly symptomatic cases.
5. Why the Combination? Complementary action: CS provide rapid symptom relief, while HA supports longer-term joint health. Minimizing CS side effects: The addition of HA may protect cartilage from the potential degenerative effects of repeated CS exposure. Dual mechanism: The mixture addresses both inflammation (CS) and joint biomechanics (HA).
6. Supporting Literature Studies have shown that while CS alone is effective short-term, HA has longer-lasting effects. The combination may result in better functional outcomes than either alone .

Some research indicates faster pain reduction and better improvement in mouth opening with HA+CS compared to monotherapy.

1. The use of a combination of hyaluronic acid (HA) and platelet-rich plasma (PRP) in the treatment of anterior disc displacement with reduction of the temporomandibular joint (TMJ) is based on the need to address both the mechanical and biological components of the disorder. anterior disc displacement with reduction is characterized by anterior displacement of the articular disc during mandibular closure with spontaneous reduction upon opening, often accompanied by joint sounds, pain, and compromised function. Prolonged displacement can lead to joint inflammation, synovitis, and eventual structural degeneration if left untreated.

Hyaluronic acid, a key component of synovial fluid, plays a critical role in maintaining joint homeostasis by enhancing lubrication, reducing friction, and providing shock absorption. It also possesses mild anti-inflammatory properties and has been shown to inhibit the activity of pro-inflammatory cytokines such as interleukin-1 and tumor necrosis factor-alpha. Clinically, intra-articular HA injections have demonstrated efficacy in reducing TMJ pain and improving mandibular mobility.

Platelet-rich plasma, an autologous concentrate rich in growth factors such as platelet-derived growth factor (PDGF), transforming growth factor-beta (TGF-β), and vascular endothelial growth factor (VEGF), promotes tissue regeneration and modulates inflammation. In the TMJ context, PRP facilitates the healing of synovial tissues, , and other soft tissues affected by repetitive disc displacement.

The combination of HA and PRP is hypothesized to exert a synergistic therapeutic effect. While HA improves the viscoelastic properties of the synovial environment and provides mechanical protection, PRP contributes biological stimulation for tissue repair and regeneration. Moreover, HA may enhance the intra-articular retention and stability of PRP, prolonging its therapeutic action.

Recent studies support the clinical efficacy of HA and PRP combination therapy. a randomized controlled trial and found that patients receiving a single intra-articular injection of HA and PRP following arthrocentesis showed significantly greater improvements in maximum mouth opening and pain reduction compared to those treated with either agent alone (PMID: 36414172). Similarly, demonstrated that the combination therapy resulted in superior functional outcomes and reduced pain 7. Objectives: The aim of this study: to evaluate the injection of hyaluronic acid and corticosteroids mixture leads to better clinical outcomes in terms of improve maximum mouth opening and reduce pain compared with hyaluronic acid and platelet rich plasma mixture in patients with TMJ internal derangement .

Hypothesis: Null hypothesis This study is alternative hypothesis research based on that the technique will be more efficient and effective in lower height groups.

Primary objective:

To assess effect of hyaluronic acid and corticosteroids mixture in assessment of maximum mouth opening , pain , clicking and movements of jaw in patients with anterior disc displacement with reduction.