When using DN on the thorax, penetration of the lung resulting in pneumothorax must be avoided. The incidence of pneumothorax due to DN has been reported to be low, less than one in 100 000 [22]. This study included patients receiving acupuncture to various body regions and not just the thorax, thus the incidence rate may be higher [19]. It is a serious adverse effect and has been reported following DN [17, 22] and can become a medical emergency [19].

The clinician should be aware that the presentation of pneumothorax following DN can vary with some patients experiencing severe pain immediately, while others may have aching pain, which may or may not be associated with immediate breathing difficulty or shortness of breath. These symptoms may present later and depend on the degree of lung involvement [17, 19, 23].

For a pneumothorax to occur the needle must penetrate through the skin, fascia, muscles, endothoracic fascia, parietal and visceral pleura [24]. Thus consideration for patient body type must be made when deciding on needle length [19]. A needle length of 3.1cm has been documented to reach lung tissue and in cadavers the average distance to the lung field at the angle of the neck was 3.3cm [25]. Thus, the choice of needle length, angle and place of insertion are important decisions that need to be made prior to embarking on DN in the thorax. The needle must always be directed away from underlying lung tissue [20]. Where possible use pincer palpation and needle tangentially to avoid penetration into the thoracic cage. Avoid DN on both sides of the thorax to prevent a bilateral pneumothorax from occurring [21]

In an attempt to minimise pneumothorax a ‘bracketing technique’ must be employed, by the practitioner placing the MFTP to be needled over a bone to prevent the needle penetrating the pleural cavity. This can decrease the chance of an adverse effect but it has., however, been documented that the needle may bypass the bone and pierce the pleural lining resulting in a pneumothorax [16, 22].

In addition, the borders of the lung must be noted. Superiorly the apex of the lung can extend 2 to 3 cm above the clavicle [16, 25] meaning that using DN in the area of the angle of the neck must be conducted with caution, for example, when treating the upper trapezius, levator scapulae, cervical paraspinals and supraspinatus MFTP’s. Inferiorly the lung can extend to the 12th rib [24] and care must be taken when needling muscles in the lower thoracic and upper lumbar regions, for example the quadratus lumborum and paraspinal muscles.

In addition, precautions are necessary for the following muscles:

Upper fibres - patient is side lying or prone. Using pincer palpation the needle is inserted perpendicular to the skin towards the practitioner’s finger. The needle can be inserted from anterior to posterior or from posterior to anterior [26]. The needle must not be left in situ without the lumbrical grip at all times until needle is removed [27].

Middle fibres – patient lying prone, block MFTP over rib using bracketing technique, aim toward the bracketed rib and use 0.25x25mm needle [27].

Lower fibres – patient side lying, using a pincer grip, direct the needle towards the spinous process one level above, use a 0.25x25mm needle[27].

Patient should be side lying, using a pincer grip, direct the needle in an anteroposterior direction towards the practitioner’s finger. Do not let go of pincer grip till needle is removed [27].

It is recommended that one needles close to the midline and not beyond the transverse process [19].

Major - bracketing of the MFTP over a rib to act as a backstop, there is potential for the needle to bypass the rib. In addition, this is a gender sensitive area and often the muscle lies deep to breast tissue making it difficult to gauge needle depth. If necessary preferably needle the lateral aspect of the muscle and direct needle obliquely [19]. Alternatively use pincer grip and a 0.25x25mm needle directed towards the practitioner’s finger [27].

Minor – Modified pincer grip, 0.3x40mm aimed antero-medial toward the practitioner’s finger [27].

Care must be taken that the needle does not go past the supraspinatus fossa into the lung [19]. Patient should be placed in the side lying position, angle the needle towards the spine of the scapulae and use a 0.25x40mm size needle [27].

The clinician must map out the boarder of the scapula, needle tangentially, avoiding lung tissue. A rare congenital foramina (incidence of 0.5 to 5.8%) has been reported in the infraspinatus fossa [16], therefore one must not rely on the scapulae bone to stop the progression of a needle [19].

Patient lies prone, trigger point is secured over a rib, with the middle and index fingers in the intercostal spaces on either side. Insert needle tangentially towards rib [28]. Needle size 0.25x25mm.

Bracketing techniques over ribs is essential [19] with patient side lying, aim towards the rib and use a 0.25x25mm needle [27].

Ensure that rib bracketing is used and limit the length of the needle, as it has been reported that the rib contact can occur at a depth of 10 -15 mm. Consideration of adiposity and needle penetration specificity must be given [19].

Never to be needled under any circumstances [27].

Patient must be prone, using the rib bracketing technique, with middle and index finger in the intercostal spaces either side of the trigger point. Insert needle perpendicular to the skin and then tangentially towards the rib [28]. Needle size 0.25x25mm.