This is a prospective single-center study included 30 patients recruited from the outpatient clinics of Physical Medicine, Rheumatology and Rehabilitation department from 2017 to 2018.
This study included all patients aged > 18 and < 45 years who had shoulder pain with overhead activity and pain score ≥ 5 on visual analog scale (VAS) in addition to painful arc or impingement signs and were diagnosed by MSUS to have partial rotator cuff tear.
The exclusion criteria were presence of other causes of shoulder pain and dysfunction as fracture, bone disease, gouty arthritis, rheumatoid arthritis, systemic diseases, such as hepatitis, diabetes mellitus, or blood diseases, referred pain from cervical spine, history of steroid injection within 6 weeks and/or non-steroidal use within the last 2 weeks, hemoglobin level less than 11 gm/dl or platelet less than 150,000 IU, and pregnancy.
This study was approved by the research ethical committee and an informed written consent was obtained from all patients prior to their inclusion in the study.
A detailed medical history and clinical examination were done for all study population.
Active and passive ranges of motion of the shoulder were assessed using goniometer. Shoulder pain was assessed by visual analog scale (VAS). Shoulder function was assessed by Shoulder Pain and Disability Index (SPADI) , which has two items the first is pain scale consists of four grades; each of them was graded from 0 to 10 (0 = no pain while 10 = maximum pain), and then we calculate the total pain score = …../50 × 100=…...%.
The second item is disability scale which consists of eight items; each of them was graded from 0 to 10 (0 = no difficulty while 10 = marked difficulty), and then we calculate the total disability score = …./80 × 100 = …..% followed by calculating the total SPADI = …../130 × 100=……%.
In addition, other tests were performed: complete blood profile (Coulter counter), erythrocyte sedimentation rate (ESR) (Westergren method), 2 h post-prandial blood sugar level (glucose oxidase method), and serum uric acid (uricase method).
High-resolution MSUS assessment of the shoulder
It was performed using a high-frequency (0–12 MHZ) linear transducer (LOGIQ 500 pro series, GE Medical Systems, USA). The examination started while the patient was setting for proper visualization of the shoulder. The transverse and longitudinal scans were applied to the shoulder for assessment of rotator cuff tendons.
Rotator cuff findings were described as follows: normal, tendinosis, tendinitis, partial tear, or full thickness tear. Ultrasound grading of rotator cuff tendon  in which grade 0: normal (hyperechoic, fibrillary echotexture), grade 1: mild tendinosis (heterogeneous echo texture with ill-defined hyperechoic regions), grade 2: severe tendinosis (diffuse abnormal hypoechogenicity without tendon volume loss), grade 3: intrasubstance abnormality (focal, well-defined, hypoechoic, or anechoic area not extending to either the bursal or articular tendon surface), grade 4: partial thickness tendon tear (focal, well-defined, hypoechoic, or anechoic area extending to either the bursal or articular surface of the tendon), grade 5: focal full-thickness tendon tear (focal, well-defined, hypoechoic, or anechoic area extending to either the bursal or articular tendon surface with tendon volume loss), grade 6: full-thickness tear (non-visualization of tendon with retraction).
PRP was prepared using a platelet concentration system (centerion 2006 England). Initially, the patient’s blood was collected under aseptic precautions. Vein puncture was done for collection of 45 ml, then mixed with 6 ml citrate in a special-designed disposable tubes (falcon tubes) for double centrifugation; first, for 15 min at 1600 rpm to separate RBCs from the plasma, and second, the plasma was separated and centrifuged for 10 min at 3200 rpm to separate platelet-rich plasma from platelet-poor plasma, and 6 ml of PRP was obtained. One milliliter of PRP was collected for blood counting to establish the platelet concentration (at least double the serum concentration), and the remaining 5 ml without any buffering or activating agent was injected under complete aseptic condition and under US guidance into the partial tear of the tendon or around it. After injection, patients were instructed to rest from overhead activity and rotatory movements of the shoulder for 2 days after the injection. Acetaminophen and compression were allowed if needed for post-injection pain control. After 2 days, a 3-week exercise program started which involved passive range of motion and Codman exercises. When the pain subsided and movement was tolerated, stretching the posterior capsule and pectoral muscles, and light resistive exercise of the rotator cuff and scapular muscles were added to the program. The patients moved to home-based program focusing on isotonic strengthening and stretching exercises for further 3 weeks. The total duration of exercise programs were 6 weeks.
All data were revised and statistically analyzed using IBM SPSS software package version 20. Descriptive statistics was performed for all variables in the study. For categorical variables, absolute counts and percentages were generated. For quantitative variables, the range, mean, SD, and SEM were calculated. Comparison of categorical data was done using the w2-test. Quantitative data were tested either using the Student t test (for parametric data) or the Mann–Whitney U test (for non-parametric significance). The correlation was calculated using the Pearson correlation coefficient (r) to determine the relationship among different variables. A p value was considered significant if it was < 0.05. Data were graphically represented using the HGW program (USA).