The frozen shoulder syndrome. Description of a new technique and five case reports using the subscapular nerve block and subscapularis trigger point infiltration.

BACKGROUND AND OBJECTIVES: A frozen shoulder is considered by some authors to be a common stage of many disorders affecting the shoulder, while others regard it as an independent idiopatic condition. A consistent finding is that subscapularis muscle trigger points play a key role in the development of the frozen shoulder syndrome. Apart from the conventional treatment, a selective subscapularis fossa nerve block combined with subscapularis trigger points infiltration, may be an effective treatment in preventing chronic pain. METHODS: In this manuscript the posterior injection technique of the subscapularis fossa nerve block is described. RESULTS: Five patients with typical symptoms of frozen shoulder, who did not respond to conventional treatment, but obtained pain relief after a combination of a subscapularis nerve block with the infiltration of trigger points, are presented. CONCLUSION: The results of this block in various painful situations of the shoulder region suggest the importance of subscapularis muscle in the etiology of the frozen shoulder. Using this technique, we could demonstrate that a subscapular nerve block and subscapularis trigger points infiltration have both a diagnostic and therapeutic value for the treatment of the frozen shoulder.