Cadaveric and in vivo validation of needle placement in the medial pterygoid muscle.

BACKGROUND: Evidence suggests that medial pterygoid muscle plays an important role in temporomandibular pain. Therapeutic approaches targeting this muscle are needed. OBJECTIVE: To determine if a solid needle accurately penetrates the medial pterygoid muscle during the application of dry needling. DESIGN: A cadaveric and human descriptive study. METHODS: Needling insertion of the medial pterygoid was conducted in 5 fresh cadaver and 5 subjects with temporomandibular pain. Needling insertion was performed using a 40 mm needle inserted at the inferior angle of the mandibular bone. The needle was advanced from an inferior to superior direction into the medial pterygoid to a maximum depth of 30 mm. In cadavers, medial pterygoid placement was assessed by observation after resecting the superficial overlying tissues. In patients, medial pterygoid placement was assessed by self-reported pain referral during insertion. RESULTS: Accurate needle penetration of the medial pterygoid was observed in all fresh cadavers and pain referral was reported by 4/5 patients during needling insertion. CONCLUSION: Results from both cadavers and patients support the assertion that needling of the medial pterygoid can be accurately conducted.

Cadaveric validation of dry needle placement in the lateral pterygoid muscle.

OBJECTIVE: The aim of this anatomical study was to determine if a needle is able to reach the lateral pterygoid muscle during the application of dry needling technique. METHODS: A dry needling approach using 2 needles of 50 to 60 mm in length, one inserted over the zygomatic process posterior at the obituary arch (for the superior head) and other inserted below the zygomatic process between the mandibular condyle and the coronoid process (for the inferior head), was proposed. A progressive dissection into 3 stages was conducted into 2 heads of fresh male cadavers. First, dry needling of the lateral pterygoid muscle was applied on the cadaver. Second, a block dissection containing the lateral pterygoid was harvested. Finally, the ramus of the mandible was sectioned by osteotomy to visualize the lateral pterygoid muscle with the needle placements. RESULTS: With the needles inserted into the cadaver, the block dissection revealed that the superior needle reached the superior (sphenoid) head of the lateral pterygoid muscle and the inferior needle reached the inferior (pterygoid) head of the muscle. At the final stage of the dissection, when the ramus of the mandible was sectioned by osteotomy, it was revealed that the superior needle entered into the belly of the superior head of the lateral pterygoid muscle. CONCLUSIONS: This anatomical study supports that dry needling technique for the lateral pterygoid muscle can be properly conducted with the proposed approach.

Effectiveness of acupuncture in the treatment of temporomandibular disorders of muscular origin: a systematic review of the last decade.

OBJECTIVE: The purpose of this review is to evaluate the effectiveness of using acupuncture treatment for temporomandibular disorders (TMD) of muscular origin according to research published in the last decade. METHODS: The information was gathered using the MEDLINE, EMBASE, CINAHL, and CISCOM databases. The inclusion criteria for selecting the studies were the following: (1) only randomized controlled trials (RCTs) were selected; (2) studies had to be carried out on patients with TMD of muscular origin; (3) studies had to use acupuncture treatment; and (4) studies had to be published in scientific journals between 1997 and 2008. Two (2) independent reviewers analyzed the methodological quality of the studies using the Delphi list. A total of four RCTs were chosen once the methodological quality was judged as being acceptable. All of the studies included in the review compared the acupuncture treatment with a placebo treatment. All of them described results that were statistically significant in relation to short-term improvement of TMD signs and symptoms of a muscular origin, except one of the analyzed studies that found no significant difference between acupuncture and sham acupuncture. CONCLUSIONS: In the authors' opinion, research into the long-term effects of acupuncture in the treatment of TMD is needed. We also recommend larger samples sizes for future studies, so the results will be more reliable.