Chapter 9

Deep Dry Needling of the Arm and Hand Muscles

César Fernández-de-las-Peñas; Javier González Iglesias; Christian Gröbli; María Palacios-Ceña; José L. Arias-Buría

Introduction

Arm pain syndromes constitute a complex entity which can arise from a wide range of different conditions. Symptoms in the upper quadrant, including the neck, shoulder, arm, forearm, or hand not related to an acute trauma or underlying systemic diseases, can be provoked by trigger points (TrPs). In fact, there are several neck and shoulder muscles with referred pain pattern perceived throughout the upper extremity, for example, the scalenes, subclavius, pectoralis minor, supraspinatus, infraspinatus, subscapularis, pectoralis major, latissimus dorsi, serratus posterior superior, and serratus anterior muscles (Simons et al., 1999). A combination of referred pain patterns from TrPs in multiple neck, shoulder, and forearm muscles can create a complex clinical pattern of nonspecific arm pain (Fernández-de-las Peñas et al., 2012). Furthermore, TrP referred pain in some muscles can mimic some neuropathic pain conditions. Qerama and colleagues (2009) demonstrated that 49% of individuals with normal electrophysiological findings in the median nerve, but with symptoms mimicking carpal tunnel syndrome, presented with active TrPs in the infraspinatus muscle with paresthesia and referred pain to the arm and fingers. In the same study, patients with mild electrophysiological signs of carpal tunnel syndrome exhibited a significantly higher occurrence of infraspinatus muscle TrPs in the symptomatic arm compared with patients with moderate to severe electrophysiological signs (33% versus 20%). Dry needling (DN) of the shoulder musculature can improve pain, sensitivity, and grip power of individuals presenting with lateral epicondylalgia (Kheradmandi et al., 2015). DN of the neck and shoulder muscles is covered in Chapter 7 (neck) and Chapter 8 (shoulders).

TrP taut bands in the musculature of the upper quadrant can be related to neural or articular dysfunctions. For instance, because the brachial plexus runs anatomically between the anterior and the medial scalene muscles, taut bands and TrPs in the scalene muscles may be related to entrapment of the brachial plexus. Similarly, shortening of the scalene muscles induced by TrP taut bands may be related to first rib dysfunctions (Ferguson & Gerwin, 2005), which means that clinicians should integrate TrP DN within the overall clinical reasoning process and management. In the current chapter we will cover deep DN of TrPs in the arm and hand muscles.

Clinical relevance of trigger points in arm and hand pain syndromes

There are only a few studies demonstrating the relevance of TrPs in the aetiology of different arm pain syndromes. The most commonly described muscle pain syndrome in the arm is probably lateral epicondylalgia (Slater et al., 2003). Fernández-Carnero and colleagues (2007) found that active TrPs in the extensor wrist musculature reproduced the pain symptoms in subjects with lateral epicondylalgia (65% extensor carpi radialis brevis; 55% extensor carpi radialis longus; 50% brachioradialis; 25% extensor digitorum communis muscle). In a subsequent study, Fernández-Carnero and collegues (2008) reported that subjects with unilateral lateral epicondylalgia also exhibited latent TrPs in muscles of the unaffected elbow (88% extensor carpi radialis brevis; 80% extensor carpi radialis longus), which may be related to the development of bilateral symptoms in this patient population. Active TrPs in the extensor carpi radialis brevis were very prevalent (68% right side; 57% left side) in women with fibromyalgia syndrome (Alonso-Blanco et al., 2011). Although these studies support the role of TrPs in arm pain syndromes, particularly in lateral epicondylalgia, further studies are needed (Shmushkevich & Kalichman, 2013). A recent study reported almost excellent agreement on TrP location and classification in the extensor carpi radialis brevis and extensor digitorum communis muscles (Mora-Relucio, et al., 2016). It is also important to consider that when TrPs are present in the brachioradialis (Mekhail et al., 1999) or extensor carpi radialis brevis muscles (Clavert et al., 2009), entrapment of the radial nerve is feasible. The only randomised clinical trial investigating the effectiveness of DN in lateral epicondylalgia observed that TrP DN was more effective than medical drug treatment at 6 months (Uygur et al., 2017).

In clinical practice an association between TrPs in the wrist flexor muscles and medial epicondylalgia is commonly seen, particularly in individuals with high muscular demands in the forearm (i.e., climbers) (González-Iglesias et al., 2011), or with low but repetitive loading (i.e., manual or office workers) (Fernández-de-las Peñas et al., 2012). Again, TrPs in the wrist flexor musculature can be also related to different nerve entrapments. For instance, as the pronator teres muscle is a common place for median nerve entrapment, commonly referred to as pronator syndrome (Lee & LaStayo, 2004), tension induced by TrP taut bands may be relevant for symptoms associated with median nerve compression (Simons et al., 1999). Similarly, the median nerve can be entrapped by TrPs in the flexor digitorum profundus and superficialis muscles, whereas the ulnar nerve can be entrapped by TrPs in the flexor carpi ulnaris and flexor digitorum profundus (Chaitow & Delany, 2008). Therefore clinicians should consider muscle–nerve interrelations in their daily practice even though no scientific study has confirmed the clinical observations.

Finally, TrPs within the intrinsic muscles of the hand, that is, the interossei and lumbricals, can also be clinically relevant for unspecific wrist–hand pain. For instance, manual laborers or boxers who have suffered a traumatic event over the wrist or the hand frequently develop TrPs in these muscles. There is clinical evidence that TrP DN of the intrinsic hand muscles such as the dorsal interossei is highly effective in these patients. TrPs in the thenar muscles are commonly seen in complaints of presumed arthritic changes in the joints of the thumb. DN of TrPs in the abductor pollicis brevis may relieve the pain associated with these joint problems (Villafañe & Herrero, 2016). Again, no scientific study has been published confirming these clinical observations.

It is important for clinicians to combine scientific and empirical evidence, as often there is no scientific evidence yet for several approaches that clinically are found to be effective. In this chapter we cover DN of TrPs in the arm and hand musculature based on clinical and scientific reasoning.

Dry needling of the arm and hand muscles

Coracobrachialis Muscle

• Anatomy: The coracobrachialis muscle originates from the coracoid process and inserts to the midportion of the humerus bone.
• Function: The coracobrachialis muscle assists in flexion and adduction of the arm at the glenohumeral joint.
• Innervation: Musculocutaneous nerve via the lateral cord from the C5 and C6 roots. It should be noted that the musculocutaneous nerve crosses the muscle belly of the coracobrachialis underneath the pectoralis major muscle.
• Referred pain: TrPs in the coracobrachialis muscle refer to the anterior aspect of the shoulder and also down the back of the arm and dorsum of the forearm to the back of the hand. The pain may mimic bicipital tendinopathy of the short head of the biceps.
• Needling technique: The patient lies supine with slight external rotation and abduction of the humerus. The muscle is needled with flat palpation. For the proximal part of the muscle between the coracoid process and the pectoralis major muscle, the tendon of the short head of the biceps brachii is palpated first. By gliding medially of the biceps tendon, the coracobrachialis muscle can be palpated. The location of the coracobrachialis muscle can be verified by flexion of the arm with the biceps in passive flexion at the elbow. The needle is inserted medial from the TrP in the coracobrachialis muscle and directed in a shallow manner towards the TrP (Fig. 9.1). Below the pectoralis major muscle the needle is inserted perpendicular to the skin from the medial to lateral side towards the humerus (Fig. 9.2).

Fig. 9.1 Dry needling of the coracobrachialis muscle (proximal).

Fig. 9.2 Dry needling of the coracobrachialis muscle (distal).

• Precautions: In the proximal part of the coracobrachialis muscle, the neurovascular bundle, which includes the median nerve, the musculocutaneous nerve, the ulnar nerve, and the brachial artery, is located underneath the muscle. In the distal part, it is dorsal and medial to the muscle. The musculocutaneous nerve passes through the muscle underneath the pectoralis muscle.

Biceps Brachii Muscle

• Anatomy: The long head of the biceps brachii muscle attaches to the upper margin of the glenoid fossa. The tendon passes through the glenohumeral joint over the head of the humerus. The short head attaches to the coracoid process of the scapula. Both heads join in a common tendon to insert at the radial tuberosity, facing the ulna in the supinated forearm.
• Function: The long head of the biceps brachii seats the humerus in the glenoid fossa when the arm is extended and loaded. Both heads assist in flexion of the arm at the shoulder and abduction of the arm at the shoulder in the externally rotated (and supinated) arm. The muscle is one of the three flexors at the elbow (together with the brachialis and the brachioradialis muscles) and acts most strongly when the hand is supinated. It also supinates the forearm when the arm is not fully extended.
• Innervation: Musculocutaneous nerve, via the lateral cord from the C5 and C6 roots. It should be noted that, anatomically, the median nerve runs medial to the muscle belly of the biceps brachii (Maeda et al., 2009).
• Referred pain: TrPs in the biceps brachii refer pain upward over the muscle and over the anterior deltoid region of the shoulder and occasionally to the suprascapular region; they can mimic symptoms of long head bicipital tendonitis. TrPs also may initiate another additional pattern of milder pain downward in the antecubital space.
• Needling technique: The patient lies supine with the arm slightly flexed. The muscle is grasped between the thumb and index and long fingers. Taut bands are identified. The muscle is commonly needled from a lateral approach to avoid needling the neurovascular bundle at the medial side, but with careful palpation it is quite easy to needle the muscle wherever clinically relevant trigger points are found. The needle is directed into the taut bands to elicit local twitch responses. The two heads of the biceps are palpated and treated separately (Fig. 9.3).

Fig. 9.3 Dry needling of the biceps brachii muscle.

• Precautions: The neurovascular bundle, which includes the median nerve, the musculocutaneous nerve, the ulnar nerve, and the brachial artery, is located medially to the biceps brachii muscle and must be avoided. In addition, avoid the radial nerve that lies along the lateral border of the distal biceps and the brachialis muscles.

Triceps Brachii Muscle

• Anatomy: The long head of the triceps brachii muscle originates from the scapula inferior to the glenoid fossa and is the only head that crosses the shoulder joint. The medial head originates from the medial portion of the humerus and the lateral head originates from the lateral side of the humerus. All three heads insert to the olecranon process on the ulna via a common tendon.
• Function: This triceps brachii muscle extends the forearm at the elbow and is an antagonist of the biceps brachii muscle. The main function of the long head of the triceps brachii muscle is adduction of the arm at the shoulder and rotation of the scapula to elevate the humeral head towards the acromion.
• Innervation: Radial nerve, via the posterior cord of the brachial plexus from spinal roots C7 and C8.
• Referred pain: TrP in the triceps brachii muscle refer up and down the posterior aspect of the shoulder, spreading potentially to the upper trapezius region, the posterior part of the arm, the dorsum of the forearm, the fourth and fifth digits (lateral head), and the lateral and sometimes the medial epicondyle (medial head).
• Needling technique: The triceps brachii can be treated with the patient in supine, sidelying, or prone position. The prone position is the preferred position as the entire triceps muscle can be treated. The muscle is palpated with a pincer palpation and the needle is directed to the underlying thumb (Fig. 9.4). The muscle can also be needled with a flat palpation, but it is harder to avoid needling into the radial nerve.

Fig. 9.4 Dry needling of the triceps brachii muscle.

• Precautions: The radial nerve runs deep to the lateral head of the triceps muscle (Rezzouk et al., 2002) and must be avoided. A recent case report showed that needling the radial nerve could cause major complications (McManus & Cleary, 2018).

Anconeus Muscle

• Anatomy: The anconeus muscle originates from the side of the olecranon process and to the dorsal surface of the ulna and inserts to the lateral epicondyle.
• Function: The anconeus muscle assists the extension movement of the forearm at the elbow and is an agonist of the triceps brachii muscle.
• Innervation: Radial nerve, via the posterior cord of the brachial plexus from spinal roots C7 and C8.
• Referred pain: TrPs in the anconeus muscle induce pain and tenderness locally to the lateral epicondyle.
• Needling technique: The patient lies in the prone position with the forearm flexed about 45 degrees at the elbow. The muscle is needled with flat palpation. As the anconeus muscle is often a thin muscle, the needle is inserted slightly proximal to the TrP and redirected towards the TrP (Fig. 9.5).

Fig. 9.5 Dry needling of the anconeus muscle.

• Precautions: None

Brachialis Muscle

• Anatomy: The brachialis muscle originates from the distal two-thirds of the humerus and inserts at the coronoid process of the ulnar tuberosity. This muscle extends into the anterior part of the joint capsule of the elbow.
• Function: The brachialis muscle flexes the forearm at the elbow.
• Innervation: Musculocutaneous nerve, via the lateral cord and by spinal roots C5 and C6.
• Referred pain: TrPs in the brachialis muscle refer to the base of the thumb and often to the antecubital region of the elbow.
• Needling technique: The patient lies supine with the elbow relaxed and slightly flexed. The muscle is needled with a flat palpation towards the humerus. The muscle is needled primarily from the lateral aspect of the arm to avoid hitting the neurovascular bundle (Fig. 9.6). When needling TrPs in the medial aspect is indicated, the neurovascular bundle and especially the median nerve must be avoided.