Is every anterior shoulder pain an impingement issue? Trigger points management for patients with anterior shoulder pain

Anterior shoulder pain of musculoskeletal origin can be challenging to identify. The differential diagnosis includes shoulder instability, bursitis of the surrounding tissue, rotator cuff injuries, and ‘impingement’ syndromes [1]. Sometimes there may be an overlap between diagnoses, producing complicated clinical results. This may cause a delay in diagnosis and hence prolong the symptomatology [2]. Myofascial pain syndrome (MPS) is one of the most frequent and overlooked cause of musculoskeletal pain due to active myofascial trigger points (MTrPs) located in muscle tissue [3]. MTrPs of the coracobrachialis, biceps brachii, and pectoralis minor can cause anterior shoulder pain, especially at the coracoid process area [4,5]. Treatment of MTrPs in the muscles can also contribute to the healing of existing pathology by reducing the restriction in the fascia and the tension in the tendon, breaking the vicious cycle of pain – spasm – pain [6]. It is difficult to diagnose when the MTrPs of these muscles, which should be considered in the differential diagnosis of anterior shoulder pain, are not viewed from the perspective of MPS. Dry needling (DN) is a treatment that is increasingly gaining popularity and is also a micro-invasive and cost-effective approach with a low risk of side effects in the treatment of MTrP [7]. This article aims to discuss the importance of the MTrPs of the muscles mentioned above in anterior shoulder pain and the treatment of the MTrPs of these muscles with the DN method. If the patient does not accept DN or has a fear of needles, spray and stretch technique, massage, ischemic compression, ultrasound or transcutaneous electrical stimulation (TENS) can also be used for the treatment of these muscles’ MTrPs [8].

MTrPs of the coracobrachialis muscle can cause pain that radiates to the anterior part of the shoulder region and the dorsal region of the arm and forearm (Figure 1(a)). The patient should be supine with the shoulder in lateral rotation. Needling should be performed with the flat palpation technique. The needle should penetrate the skin from the medial to the lateral direction, just medial to the biceps muscle, with a perpendicular angle (Figure 1(b)). 0.25 × 13 mm needle size is considered appropriate [4].

Figure 1.

Pain referral pattern and dry needling procedure of the muscles that can cause anterior shoulder pain, (a); trigger point locations and pain referral pattern of the coracobrachialis muscle (b); application of dry needling to the coracobrachialis muscle with the flat palpation technique, (c); trigger point locations and pain referral pattern of the biceps brachii muscle, (d); application of dry needling to the biceps brachii muscle with the pincer palpation technique, (e); trigger point locations and pain referral pattern of the pectoralis minor muscle (f); application of dry needling to the pectoralis minor muscle with the pincer palpation technique.

Radiating pain from the biceps brachii muscle's MTrPs may occur on the muscle itself, in the anterior deltoid region, and occasionally in the suprascapular area (Figure 1(c)). Needling is performed with the patient in the supine position. The elbow should be positioned in slight flexion. Needling is performed with the pincer palpation technique. The needle should penetrate the skin from the lateral to the medial direction, aiming the index finger between the thumb and index fingers of the clinician (Figure 1(d)). 0.30 × 30 mm needle size should be used [4].

MTrPs of the pectoralis minor muscle may cause pain in the pectoral region, the anterior part of the shoulder region, and along the arm from the ulnar side to the fourth and fifth fingers (Figure 1(e)). Needling is performed with the patient in the supine position. The arm should be in slight abduction. The clinician should be positioned on the side of the patient’s pathology. In female patients, the patient is asked to pull the chest on the side of the pathology toward the opposite side. Needling should be done with the flat palpation technique. The needle should penetrate the skin from the lateral to the cranial-medial direction, targeting the coracoid process (Figure 1(f)). 0.30 × 30 mm needles are adequate. In obese patients, 0.3 × 40–50 mm needles can be used [4].

There is increasing evidence in the literature for the use of DN for shoulder pain. Arias-Buría et al. [9] reported that patients with subacromial pain syndrome experienced larger clinical improvements in their shoulder pain-related impairments when DN was added to an exercise program. Blanco-Díaz et al. [10] reported improvements in all cases of pain-related shoulder injuries, with the application of DN combined with physiotherapy being the most effective treatment in their systematic review. Arias-Buría et al. [11] also reported that integrating a single session of DN in the first week of physical therapy treatment may help patients with postoperative shoulder pain experience faster functional improvements.

In summary, MTrPs may be the primary source of anterior shoulder pain or secondary to the underlying disease. We conclude that MTrPs of the coracobrachialis, biceps brachii and pectoralis minor muscles should be considered in the differential diagnosis of anterior shoulder pain. The inclusion of MTrPs management of these muscles in treatment protocols could positively affect the treatment outcomes. Along with DN treatment, it is also very important to implement a personalized physical therapy program, make necessary modifications in activities of daily living and educate patients [10]. Although there is no consensus in the literature, dry needling is recommended to be performed once weekly for a total of 3 sessions [12].

Biographies

Mustafa Hüseyin Temel is a physical medicine and rehabilitation specialist that works at Üsküdar State Hospital, Turkey. He is interested in ultrasound-guided injections, dry needling, and musculoskeletal pain. It is his dream to bring new and different perspectives to literature.

Fatih Bağcıer is a physical medicine and rehabilitation specialist that works in Çam and Sakura City Hospital, Turkey. The author, who has several publications on dry needling and myofascial pain syndrome and is the editor of two textbooks, is interested in dry needling therapy and ultrasound-guided pain interventions.

Disclosure statement

No potential conflict of interest was reported by the authors.