Elasticity of the Coracoacromial Ligament in Shoulders with Rotator Cuff Tears: Measurement with Ultrasound Elastography

Background: The symptoms of rotator cuff tear vary and may even be absent. Thus, the symptoms cannot be explained solely by the presence of rotator cuff tear, and other factors are thought to be involved. Because the rotator cuff comes in contact with the coracoacromial ligament, the elasticity of the ligament may be a factor of the symptoms. The purpose of this study was to clarify the elasticity of the coracoacromial ligament in live shoulders with rotator cuff tears. Methods: Forty-one shoulders in 24 persons were enrolled in this study. The average age was 52 years old (range, 15 - 84 years old). We investigated the presence of rotator cuff tear and measured the elasticity of the coracoacromial ligament by ultrasound elastography (EUB-7500, HITACHI, Japan). Ultrasound elastography was a useful method to quantify the strain of soft tissue when pressure was added. The strain ratio (the ratio of strain of the coracoacromial ligament to that of the rotator cuff) was used as the index of the elasticity of coracoacromial ligament. Thus, the higher the strain ratio was, the softer the ligament was. Results: The strain ratio of the coracoacromial ligaments without rotator cuff tear showed a negative correlation to the age (r = ﹣0.825, P 0.01). The strain ratio of the ligaments with rotator cuff tear (23.75 ± 15.05, 69.6 years old) was higher than that of the older ligaments without cuff tear (12.62 ± 7.94, 64.6 years old) (P = 0.0486). In shoulders with rotator cuff tear, the strain ratio of the ligaments with pain (14.37 ± 10.15, 66.7 years old) was lower than that of ligaments without pain (33.12 ± 13.59, 69.1 years old) (P = 0.0221). Conclusions: The coracoacromial ligament became stiffened with aging but softened with the existence of rotator cuff tear. The ligaments with symptomatic cuff tear are more stiffened than the ligaments with asymptomatic cuff tear.

Differences in the Length and Thickness of the Coracoacromial Ligament between Normal Shoulders and Shoulders with Rotator Cuff Tears

Although the relationship between the material properties of the coracoacromial ligament and rotator cuff tears has been clarified, it is difficult to evaluate these properties in the clinical setting. The purpose of this study was to clarify the relationship between rotator cuff tears and the length and thickness of the coracoacromial ligament in living shoulders, in order to assess the potential use of these parameters as clinical indicators of the possible risk or progression of rotator cuff tears. Thirty-five volunteers (46 shoulders, mean age: 52 years) were enrolled. The presence or absence of rotator cuff tears and the length and thickness of the coracoacromial ligament were evaluated by ultrasonography. Longitudinal images of the coracoacromial ligaments with the acromion and coracoid process as landmarks were obtained, and the lengths of the ligaments were measured using acoustic shadows as the index. On the same screens, the thicknesses at the center of the ligaments were measured. Ligaments in shoulders with a rotator cuff tear were significantly shorter than ligaments in shoulders without a rotator cuff tear (25.9 ± 2.5 mm vs. 28.6 ± 1.7 mm, respectively;P < 0.0001). There was no significant difference in the thicknesses of the ligaments. The length and thickness of the coracoacromial ligament of living shoulders were easily evaluated with ultrasonography in the present study, and the coracoacromial ligament was found to be significantly shorter in shoulders with a rotator cuff tear. The risk and progression of rotator cuff tears can be evaluated clinically by measuring the length of the coracoacromial ligament.

LUtarjet-limit unique coracoid osteotomy Latarjet(With video)

Background:The Latarjet procedure is an effective technique for the treatment of recurrent anterior shoulder dislocation with glenoid bone loss.However,the inevitable destruction of the coracoacromial arch may result in humeral head translation.The aim of the study is to introduce a modified Latarjet technique with coracoacromial arch preservation as well as its short term clinical outcomes.Methods:We propose a novel individualized flexible arthroscopic suture button fixation Latarjet technique called‘LUtarjet’with video.Precise measurements of the coracoid process,glenoid deficiency and osteotomy plane were made preoperatively.Only three arthroscopic portals were needed and limit unique coracoid osteotomy was performed with coracoacromial arch preser-vation.The mini window splitting of the subscapularis was performed from the posterior to the anterior direction and the split window was as small as 8-10 mm in length.Results:A total of 27 patients(25.6±5.4 years)were included in the study.The average surgical durationwas 55.6±6.3 min and the mean follow-up timewas 8.1±1.5 months.The functional score was significantly improved at the last follow-up.Radiologic evidence showed that the bone graft healing was placed in the desired position.No complications were found.Conclusions:We present a fast,easy,accurate,safe arthroscopic‘LUtarjet’technique called FEAST that can simplify the arthroscopic Latarjet process and achieve a satisfactory bone graft position and satisfactory short-term clinical outcomes.Level of evidence:IV,case series.