Pertinent Dry Needling Considerations for Minimizing Adverse Effects – Part One

This comprehensive clinical commentary, published by Halle and colleagues in 2016, represents a fundamental educational milestone in the safe practice of dry needling. The article arises from an important observation made during an introductory dry needling course, where the authors noted that some sites commonly taught for dry needle insertion coincided with regions that other healthcare professionals are advised to avoid due to anatomical risks. The technique involves the insertion of solid filiform needles (0.20-0.25 mm in diameter) into muscular trigger points to reduce pain, decrease muscle tension, and accelerate the return to active rehabilitation. The exponential growth of the technique is evident: from a single PubMed reference in 2000 to 51 new references in 2014, expanding from a single physical therapy program offering training in 2006 to multiple programs today.

The main focus of the article is on the thoracic region, where several needling points are used to treat conditions such as adhesive capsulitis of the shoulder, upper-quarter myofascial pain, neck pain, and headaches. The authors emphasize that, although the "bracketing" technique (using bone as a backstop) is commonly taught to minimize risks, accidents can occur when the needle slides along a rib and penetrates more deeply than anticipated.

Adverse events documented in the literature vary significantly in incidence. The study by Witt et al., involving 229,230 patients and approximately 2.2 million treatment sessions, demonstrated that 8.6% of patients reported at least one adverse event, with 2.2% requiring additional treatment. Although most events are mild (bleeding or pain), serious complications such as pneumothorax can occur.

The article presents three detailed cases of pneumothorax associated with dry needling. The first case involved a physician participating in a workshop, where a 0.3 x 50 mm needle was used in the iliocostalis muscle. The participant developed diffuse chest pain, dry cough, and shortness of breath, with radiographic diagnosis confirming a 20% pneumothorax on the second day post-procedure. The second case occurred during acupuncture treatment for neck pain, with symptoms developing 4-5 hours after treatment.

The third case, reported in the electromyography literature, showed symptoms within 40 minutes after puncture of the rhomboid major muscle.

The detailed anatomical considerations reveal the complexity of the thoracic region. The pulmonary apex can extend 2-3 cm above the clavicular line, creating risk for needling in the upper trapezius and lower cervical paravertebral region. Individual anatomical variability is significant—in the cadaveric study by Honet et al., five of 23 cadavers had lung tissue extending above the clavicle, with a minimum skin-to-lung distance of only 3.1 cm.

Inferiorly, the lungs extend down to the level of the 12th rib posteriorly, creating risks for needling muscles such as the iliocostalis. The relatively thin chest wall, composed of specialized intercostal muscles, offers limited protection. The three intercostal muscles (external, internal, and innermost) are arranged in different orientations to provide structural strength, but are too thin to allow safe direct needling.

The article provides specific guidance for different muscles. For the lower cervical paravertebrals, medial positioning to the transverse processes is recommended. The supraspinatus muscle is generally safe due to the bony backstop of the supraspinous fossa, although a reported case demonstrates that positioning at the midpoint of the scapular spine can be risky. The rhomboid muscles present particular challenges due to their deep location and proximity to the chest wall.

For the pectoralis major, the authors recommend needling at the lateral portion near the humeral insertion, with oblique orientation to avoid the lung fields. Sternal needling requires special care due to the possibility of congenital sternal foramina (incidence of 5-8%), which can allow inadvertent penetration of the pericardial sac.

The clinical implications are clear: although dry needling is an effective and evidence-based therapeutic modality, its safe application requires deep anatomical knowledge and meticulous technique. Practitioners must be aware of the potential risks, implement adequate informed consent, and maintain open communication with patients during treatment.

This clinical commentary establishes essential foundations for safe practice, emphasizing the principle of "primum non nocere" (first, do no harm). The promised second part will address the abdomen, pelvis, back, and other considerations such as vasovagal response and informed consent, completing a comprehensive guide to minimizing adverse events in dry needling.