The Effect of Scapular Fixation on Scapular and Humeral Head Movements during Glenohumeral Axial Distraction Mobilization

Abstract

Background and Objectives: Glenohumeral axial distraction mobilization (GADM) is a usual mobilization technique for patients with shoulder dysfunctions. The effect of scapular fixation on the movement of the scapula and the humeral head during GADM is unknown. To analyze the caudal movement of the humeral head and the rotatory movement of the scapula when applying three different intensities of GADM force with or without scapular fixation. Materials and Methods: Fifteen healthy subjects (mean age 28 ± 9 years; 73.3% male) participated in the study (twenty-eight upper limbs). Low-, medium- and high-force GADM in open-packed position were applied in scapular fixation and non-fixation conditions. The caudal movement of humeral head was evaluated by ultrasound measurements. The scapular rotatory movement was assessed with a universal goniometer. The magnitude of force applied during GADM and the region (glenohumeral joint, shoulder girdle, neck or nowhere) where subjects felt the effect of GADM mobilization were also recorded. Results: A greater caudal movement of the humeral head was observed in the non-scapular fixation condition at the three grades of GADM (p < 0.008). The rotatory movement of the scapula in the scapular fixation condition was practically insignificant (0.05–0.75°). The high-force GADM rotated scapula 18.6° in non-scapular fixation condition. Subjects reported a greater feeling of effect of the techniques in the glenohumeral joint with scapular fixation compared with non-scapular fixation. Conclusions: The caudal movement of the humeral head and the scapular movement were significantly greater in non-scapular fixation condition than in scapular fixation condition for the three magnitudes of GADM force.

Effect of Scapular Fixation on Lateral Movement and Scapular Rotation during Glenohumeral Lateral Distraction Mobilisation

“…The medium-force GLDM was when a marked resistance was first felt (the “first stop”), and the high-force GLDM was when there was maximum tissue resistance. This procedure was applied in the same sequence and was repeated twice with 30 s rest between repetitions [ 22 ]. The value of the applied force for the analysis was the average of the two tests.…”

“…In clinical practice, the GLDM technique is applied with scapular fixation [ 17 ]. The aim is to have a better control of the translational motion and to prevent a scapular motion produced by the applied force [ 22 ]. It also prevents the applied force from being directed to other structures in the scapulothoracic and cervical region, which could cause harm in these regions [ 23 , 24 , 25 ].…”

“…A similar technique has been studied as the glenohumeral axial distraction technique, which produces a caudal slip by increasing the subacromial space [ 26 , 27 , 28 ]. A recent study demonstrated that fixation condition affected glenohumeral axial distraction mobilisation [ 22 ]. However, we do not know whether the GLDM technique produces a lateral displacement to the glenoid and its magnitude when applied clinically.…”

“…However, we do not know whether the GLDM technique produces a lateral displacement to the glenoid and its magnitude when applied clinically. We are also unaware of the differences between scapular and non-scapular fixation conditions with different mobilisation degrees, as Kaltenborn described [ 22 ].…”

“…Imaging methods assess the motions that occur in the glenohumeral region [ 30 , 31 ]. Ultrasound is a real-time, non-invasive, and non-injurious imaging method used to assess patients compared with similar techniques [ 22 , 32 ]. The response variable to assess the effect of GLDM could be lateral movement [ 27 , 33 , 34 ].…”