Subacromial anaesthetics increase asymmetry of scapular kinematics in patients with subacromial pain syndrome.

BACKGROUND: Subacromial pain syndrome (SAPS) and scapular dyskinesis are closely associated, but the role of pain is unknown. We hypothesized that pain results in asymmetrical scapular kinematics, and we expected more symmetrical kinematics after infiltration of subacromial anaesthetics. OBJECTIVE: To investigate the effect of subacromial anaesthetics on scapular kinematics in patients with SAPS. DESIGN: Observational cohort study. METHODS: We evaluated shoulder kinematics in 34 patients clinically and radiologically (magnetic resonance arthrography) identified with unilateral SAPS using three-dimensional electromagnetic motion analysis (Flock of Birds). Scapular internal rotation, upward rotation and posterior tilt of the affected shoulder were compared with the kinematics of the unaffected shoulder and following subacromial anaesthetics. Additionally, the association of pain (Visual Analogue Scale, VAS) and scapular rotation was analysed. RESULTS: Compared with the contralateral healthy shoulder, 5° more (95% CI 0.4-9.7, p = 0.034) scapular internal rotation was observed in the affected shoulder at 110-120° of abduction. Following subacromial anaesthetics in the affected shoulder, internal rotation increased (2°, 95% CI 0.5-3.9, p = 0.045) and posterior tilt decreased (3°, 95% CI 1.5-5.0, p = 0.001) at 110-120° of abduction. Less scapular upward rotation was significantly associated with higher pain scores before infiltration (R = 0.45, p = 0.013). CONCLUSIONS: More scapular internal rotation was observed in affected shoulders of patients with SAPS compared with unaffected shoulders. Subacromial infiltration did not restore kinematics toward symmetrical scapular motion. These findings suggest that subacromial anaesthesia is not an effective means to instantly restore symmetry of shoulder motion.

Subacromial impingement syndrome as a consequence of botulinum therapy to the upper trapezii: a case report.

Scapular upward rotation is predominantly achieved via a force coupling involving the upper and lower trapezius and the serratus anterior. Although studies have shown a relationship between abnormal scapular motion and subacromial impingement, it has been unclear whether the altered scapular biomechanics represent a cause, or consequence, of impingement. We present a 49-year-old woman with refractory myofascial pain of many years duration who developed subacromial impingement syndrome (SIS) following a series of botulinum toxin injections to the bilateral upper trapezii. Although botulinum therapy effectively reduced the patient's refractory myofascial pain, signs and symptoms of SIS developed in association with the upper trapezii weakness after the third set of injections. Botulinum therapy was discontinued and nonsteroidal anti-inflammatory medication markedly reduced the new symptoms, which completely resolved within 3 months. This case, which afforded a unique opportunity to follow the consequences of weakening scapular stabilizers over time, provides evidence for the etiologic role of scapular dyskinesis in SIS and shows that SIS is a potential complication of botulinum therapy for myofascial pain involving the scapular stabilizers.

Rheumatological complications associated with the use of indinavir and other protease inhibitors.

Several cases are reported of rheumatological pathology (temporomandibular dysfunction, frozen shoulder, Dupuytren's disease, and tendinitis) most probably related to the intake of indinavir in HIV positive patients. A survey using an anonymous questionnaire of 878 people with HIV infection treated with antiretroviral drugs suggests that other protease inhibitors may also cause arthralgia.