Rheumatol Int DOI 10.1007/s00296-014-2966-6
Original Article
Comparison of the therapeutic effects of intramuscular subscapularis and scapulothoracic bursa injections in patients with scapular pain: a randomized controlled trial Won Hyuk Chang · Yong Wook Kim · Sungsik Choi · Sang Chul Lee
Received: 20 July 2013 / Accepted: 8 February 2014 © Springer-Verlag Berlin Heidelberg 2014
Abstract Scapulothoracic bursitis contributes to considerable morbidity in some patients with scapular pain. A scapulothoracic bursa injection can induce symptomatic relief; however, blind injections into the scapulothoracic bursa may involve injecting into the subscapularis muscle itself. The aim of this study was to compare the therapeutic effects of intramuscular injections into the subscapularis under ultrasound (US) guidance with those of blind scapulothoracic bursa injections in patients with scapular pain. This study was a single-center, prospective, randomized, single-blinded, controlled clinical trial. Thirty-six patients with suspected scapulothoracic bursitis, who met the inclusion criteria, were recruited between January 2009 and December 2012. We performed three US-guided intramuscular injections into the subscapularis muscle or three blind scapulothoracic bursa injections at 1-week intervals. A visual analogue scale (VAS) and the Rubin scale at baseline and at 1, 2, and 3 weeks after the last injections were examined and again at 3 months after the last injections by a blinded investigator. Adverse effects were monitored. The VAS scores at baseline were 7.7 ± 1.3 and 7.8 ± 1.4 in the intramuscular injection and scapulothoracic bursa injection W. H. Chang Department of Physical and Rehabilitation Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea Y. W. Kim · S. C. Lee (*) Department and Research Institute of Rehabilitation Medicine, Yonsei University College of Medicine, 50 Yonsei‑ro, Seodaemun‑gu, Seoul 120‑752, South Korea e-mail: [email protected] S. Choi Department of Physical Medicine & Rehabilitation, Myongji Hospital, Gyunggi, South Korea
groups, respectively. Mean VAS scores after the intramuscular injections were 3.8, 2.7, 1.3, and 3.5, and mean VAS scores after scapulothoracic bursa injections were 4.1, 2.4, 1.6, and 2.9 at 1, 2, 3 weeks and at 3 months after the last injections. VAS scores decreased significantly after the injections in each group (p ≤ 0.05). However, no significant difference was observed between intramuscular injection into the subscapularis and the scapulothoracic bursa injection. No serious complications were encountered. In conclusion, injections at the scapulothoracic bursa without US guidance did not exclude the possibility of an effect of steroid on the subscapularis muscle, as both intramuscular injections into the subscapularis and scapulothoracic bursa injections in patients with scapular pain provided equal symptomatic relief, and all patients developed tenderness in their subscapularis muscle. Keywords Scapula · Injections · Ultrasonography · Pain
Introduction Pain and discomfort under the scapula are diffuse and nonspecific. Treatment can be problematic in patients with scapular pain who do not have a readily apparent structural abnormality. Most scapular pain and discomfort are related to various causes such as cervical radiculitis or radiculopathy, muscle strain of the scapula rotators, or glenohumeral joint problems that result in excessive scapular motion or overuse syndromes with muscle fatigue [1]. Scapulothoracic bursitis contributes to considerable morbidity in some patients with scapular pain [2]. The causes of scapulothoracic bursitis include anatomic scapular or thoracic variations, muscle abnormalities, and bony or soft tissue masses. Although three-dimensional
13
computed tomography and magnetic resonance imaging aid in detecting these abnormalities, diagnosis and management of snapping scapula syndrome remain challenging. Selective injections of local anesthetic or steroid can be useful for identifying a symptomatic bursa. Symptomatic improvement following injection can help substantiate the diagnosis [3]. We previously suggested that scapulothoracic bursitis should be considered when treating patients with perimarginal scapular pain or subscapular pain and that steroid plus hyaluronate injections into the scapulothoracic bursa provide an effective means of treating patients with scapulothoracic bursitis [4]. However, the effect of a blind scapulothoracic bursa injection does not exclude the possibility of an effect on the serratus anterior and/or subscapularis muscle because of inaccurate delivery. Although an image-guided injection can differentiate the bursa from the muscle, it is technically difficult to inject the targeted area under the scapula with a conventional image-guided method. Therefore, we doubted that a blind injection into the scapulothoracic bursa involves injection into the subscapularis muscle. We recently observed that a significant number of patients compatible with the criteria of scapulothoracic bursitis also exhibit tenderness of the subscapularis muscle. The subscapularis can be palpated when the shoulder of a patient is placed in a position of flexion, external rotation, and abduction [5]. A safe and accurate injection technique into the subscapularis muscle has been introduced using ultrasound (US) guidance for treating spasticity [6]. The present randomized clinical trial compared the therapeutic effects of intramuscular injections into the subscapularis under US guidance with those of blind scapulothoracic bursa injections.
Rheumatol Int
presence of other obvious pathology for rotator cuff pain, such as a fracture or osteonecrosis; bilateral scapular pain that required pain improvement to be further investigated; absolute contraindications for the injection procedure such as local infection, dermatologic conditions that precluded adequate skin preparation, a tumor at the injection site, a history of allergy to local anesthetic agents or steroid, gross coagulation defects; and the presence of an unstable medical condition or a known uncontrolled systemic disease. This study was designed as a prospective, randomized, single-blinded, clinical trial that compared intramuscular subscapularis with scapulothoracic bursa injections. Patients were randomly grouped into the intramuscular injection or scapulothoracic bursa injection groups using a stratified randomization procedure with a permuted block size of four and a computer program that balanced ages ( 0.05 by the Kolmogorov–Smirnov test). Therefore, the independent t test and repeated-measures analysis of variance (ANOVA) were used for comparative statistics. The general characteristics or baseline data were compared between each group using the independent t test or chi-square test. The effects of intramuscular injections into the subscapularis or the scapulothoracic bursa injections were evaluated using repeated-measures ANOVA with time as the within-subject factors and group (intramuscular and scapulothoracic bursa injection groups) as the between-subject factors. A post hoc analysis was performed with a Bonferroni correction. Statistical significance was accepted at p 0.05). Symptom duration was based on the presence of intractable pain, not on vague discomfort or mild pain. All 36 patients had tenderness in the subscapularis muscle when the subscapularis was palpated in the shoulder positions of flexion, external rotation, and abduction. No significant difference in the VAS scores at baseline was observed between the two groups. Repeatedmeasures ANOVA showed a significant effect of time on the VAS scores in the intramuscular injection group and the scapulothoracic bursa injection group, respectively (F(4,68) = 82.299, p
Original Article
Comparison of the therapeutic effects of intramuscular subscapularis and scapulothoracic bursa injections in patients with scapular pain: a randomized controlled trial Won Hyuk Chang · Yong Wook Kim · Sungsik Choi · Sang Chul Lee
Received: 20 July 2013 / Accepted: 8 February 2014 © Springer-Verlag Berlin Heidelberg 2014
Abstract Scapulothoracic bursitis contributes to considerable morbidity in some patients with scapular pain. A scapulothoracic bursa injection can induce symptomatic relief; however, blind injections into the scapulothoracic bursa may involve injecting into the subscapularis muscle itself. The aim of this study was to compare the therapeutic effects of intramuscular injections into the subscapularis under ultrasound (US) guidance with those of blind scapulothoracic bursa injections in patients with scapular pain. This study was a single-center, prospective, randomized, single-blinded, controlled clinical trial. Thirty-six patients with suspected scapulothoracic bursitis, who met the inclusion criteria, were recruited between January 2009 and December 2012. We performed three US-guided intramuscular injections into the subscapularis muscle or three blind scapulothoracic bursa injections at 1-week intervals. A visual analogue scale (VAS) and the Rubin scale at baseline and at 1, 2, and 3 weeks after the last injections were examined and again at 3 months after the last injections by a blinded investigator. Adverse effects were monitored. The VAS scores at baseline were 7.7 ± 1.3 and 7.8 ± 1.4 in the intramuscular injection and scapulothoracic bursa injection W. H. Chang Department of Physical and Rehabilitation Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea Y. W. Kim · S. C. Lee (*) Department and Research Institute of Rehabilitation Medicine, Yonsei University College of Medicine, 50 Yonsei‑ro, Seodaemun‑gu, Seoul 120‑752, South Korea e-mail: [email protected] S. Choi Department of Physical Medicine & Rehabilitation, Myongji Hospital, Gyunggi, South Korea
groups, respectively. Mean VAS scores after the intramuscular injections were 3.8, 2.7, 1.3, and 3.5, and mean VAS scores after scapulothoracic bursa injections were 4.1, 2.4, 1.6, and 2.9 at 1, 2, 3 weeks and at 3 months after the last injections. VAS scores decreased significantly after the injections in each group (p ≤ 0.05). However, no significant difference was observed between intramuscular injection into the subscapularis and the scapulothoracic bursa injection. No serious complications were encountered. In conclusion, injections at the scapulothoracic bursa without US guidance did not exclude the possibility of an effect of steroid on the subscapularis muscle, as both intramuscular injections into the subscapularis and scapulothoracic bursa injections in patients with scapular pain provided equal symptomatic relief, and all patients developed tenderness in their subscapularis muscle. Keywords Scapula · Injections · Ultrasonography · Pain
Introduction Pain and discomfort under the scapula are diffuse and nonspecific. Treatment can be problematic in patients with scapular pain who do not have a readily apparent structural abnormality. Most scapular pain and discomfort are related to various causes such as cervical radiculitis or radiculopathy, muscle strain of the scapula rotators, or glenohumeral joint problems that result in excessive scapular motion or overuse syndromes with muscle fatigue [1]. Scapulothoracic bursitis contributes to considerable morbidity in some patients with scapular pain [2]. The causes of scapulothoracic bursitis include anatomic scapular or thoracic variations, muscle abnormalities, and bony or soft tissue masses. Although three-dimensional
13
computed tomography and magnetic resonance imaging aid in detecting these abnormalities, diagnosis and management of snapping scapula syndrome remain challenging. Selective injections of local anesthetic or steroid can be useful for identifying a symptomatic bursa. Symptomatic improvement following injection can help substantiate the diagnosis [3]. We previously suggested that scapulothoracic bursitis should be considered when treating patients with perimarginal scapular pain or subscapular pain and that steroid plus hyaluronate injections into the scapulothoracic bursa provide an effective means of treating patients with scapulothoracic bursitis [4]. However, the effect of a blind scapulothoracic bursa injection does not exclude the possibility of an effect on the serratus anterior and/or subscapularis muscle because of inaccurate delivery. Although an image-guided injection can differentiate the bursa from the muscle, it is technically difficult to inject the targeted area under the scapula with a conventional image-guided method. Therefore, we doubted that a blind injection into the scapulothoracic bursa involves injection into the subscapularis muscle. We recently observed that a significant number of patients compatible with the criteria of scapulothoracic bursitis also exhibit tenderness of the subscapularis muscle. The subscapularis can be palpated when the shoulder of a patient is placed in a position of flexion, external rotation, and abduction [5]. A safe and accurate injection technique into the subscapularis muscle has been introduced using ultrasound (US) guidance for treating spasticity [6]. The present randomized clinical trial compared the therapeutic effects of intramuscular injections into the subscapularis under US guidance with those of blind scapulothoracic bursa injections.
Rheumatol Int
presence of other obvious pathology for rotator cuff pain, such as a fracture or osteonecrosis; bilateral scapular pain that required pain improvement to be further investigated; absolute contraindications for the injection procedure such as local infection, dermatologic conditions that precluded adequate skin preparation, a tumor at the injection site, a history of allergy to local anesthetic agents or steroid, gross coagulation defects; and the presence of an unstable medical condition or a known uncontrolled systemic disease. This study was designed as a prospective, randomized, single-blinded, clinical trial that compared intramuscular subscapularis with scapulothoracic bursa injections. Patients were randomly grouped into the intramuscular injection or scapulothoracic bursa injection groups using a stratified randomization procedure with a permuted block size of four and a computer program that balanced ages ( 0.05 by the Kolmogorov–Smirnov test). Therefore, the independent t test and repeated-measures analysis of variance (ANOVA) were used for comparative statistics. The general characteristics or baseline data were compared between each group using the independent t test or chi-square test. The effects of intramuscular injections into the subscapularis or the scapulothoracic bursa injections were evaluated using repeated-measures ANOVA with time as the within-subject factors and group (intramuscular and scapulothoracic bursa injection groups) as the between-subject factors. A post hoc analysis was performed with a Bonferroni correction. Statistical significance was accepted at p 0.05). Symptom duration was based on the presence of intractable pain, not on vague discomfort or mild pain. All 36 patients had tenderness in the subscapularis muscle when the subscapularis was palpated in the shoulder positions of flexion, external rotation, and abduction. No significant difference in the VAS scores at baseline was observed between the two groups. Repeatedmeasures ANOVA showed a significant effect of time on the VAS scores in the intramuscular injection group and the scapulothoracic bursa injection group, respectively (F(4,68) = 82.299, p
