The aim of this study was to assess hypertrophy of the extra-articular
tendon of the long head of biceps (LHB) in patients with a rotator
cuff tear. The study involved 638 shoulders in 334 patients (175 men, 159
women, mean age 62.6 years; 25 to 81) with unilateral symptomatic
rotator cuff tears. The cross-sectional area (CSA) of the LHB tendon
in the bicipital groove was measured pre-operatively in both shoulders
using ultrasound. There were 154 asymptomatic rotator cuff tears
in the contralateral shoulder. Comparisons were made between those
with a symptomatic tear, an asymptomatic tear and those with no
rotator cuff tear. In the affected shoulders, the CSAs were compared
in relation to the location and size of the rotator cuff tear. Aims
Patients and Methods
Massive rotator cuff tears and consequent cuff-deficient arthritis (CTA) of the shoulder can cause severe shoulder dysfunction in the elderly. Reverse total shoulder arthroplasty (RTSA) has been widely used for treatment of CTA in all over the world since its introduction in the 90's. In Japan, however, we have just started to clinically use RTSA from April 2014. In addition, we have only one choice of the implants (Aequalis Reverse, Tornier) currently, and only one size of the base-plate of the glenoid component (29 mm in diameter) is available so far. Japanese, especially elderly people, have generally smaller figure than Caucasians. We are not sure whether the base-plate would fit for the smaller Japanese. The purpose of this study was to measure the size of the glenoids in Japanese using CT images and to examine that they would fit the 29 mm base-plate. The shoulders without osteoarthritis of the glenohumeral joint were eligible for the study. The subjects consisted of 30 shoulders including 10 elderly males, 10 elderly females, and 10 younger males, and the mean ages were 73 (range, 63–81), 74 (range, 65–89), and 32 (range, 27–36) years old, respectively. Mean heights and weights were 164 cm (range, 156–179) and 59 kg (range, 49–72), 154 cm (range, 151–161) and 57 kg (range, 48–65), and 173 cm (range, 162–179) and 72 kg (range, 61–100), respectively. CT images with a 0.3 mm slice pitch were used for the analysis. The images were loaded into a DICOM viewer (OsiriX), and a slice for simulated implantation of the base-plate was created using the multi-planar reconstruction (Figure 1), which had 10° of inferior tilt to the glenoid face. The width of the glenoid in the antero-posterior direction was measured at 14 mm above the inferior edge of the glenoid.Background
Methods
