Shoulder impingement syndrome in water polo players: muscle shortening manoeuvre controls pain intensity, recovers function and normalizes sonographic parameters

Purpose To evaluate the effects of muscle shortening manoeuvre (MSM) by sonography (US) in professional water poloplayers with shoulder impingement syndrome (SIS).Methods Twenty-four professional water polo players (mean age: 22.13 ± 3.34) with SIS were assigned to one of 2 differenttreatment interventions: Group (1) MSM: a series of fast accelerations in the upward direction was applied to the upperlimb that’s connected to a spring through a metal plate with a ring. The ring was linked to a pulley system that was submittedto forces acting in the opposite direction (added mass). Group (2) Simple traction: the series of fast accelerations wereperformed without the springs. Pain intensity, Yocum and Hawkins tests for SIS, Neer’s impingement sign, range of motion,muscle strength and shoulder US were assessed. The examination was performed before, immediately after and 30 daysafter each treatment to study the US width of subacromial-subdeltoid bursa (SSB), thickness of supraspinatus (ST), longbiceps tendons (LBT); hypoechoic halo of surrounding the long biceps (LBH) and subscapular tendons (STH); width ofacromio-clavicular joint capsule (ACJ) and the distance between bone heads (ACD). Impingement sign (IS) was evaluatedby dynamic examination.Results Immediately after treatment with MSM, pain was much reduced (p = 0.002); Yocum and Hawkins tests weredecreased (p = 0.008, p = 0.031); Neer’s impingement sign was negative; range of motion and muscle strength were increased.US showed that the following parameters were significantly reduced: SSB (p = 0.001), LBT (p = 0.014), LBH (p = 0.014),SSH (p = 0.002), ACJ (p = 0.004), ACD (p = 0.001). IS was no more detected. After 30 days, the improvement of clinicaland US findings was maintained. In the control group, after simple traction, no clinical amelioration of US parameters wasfound immediately after the procedure.Conclusion These data show that MSM could be significantly and rapidly effective against pain and the loss of function dueto shoulder impingement in water polo players.