Ken Yamaguchi

Learn More
BACKGROUND The impact of a recurrent defect on the outcome after rotator cuff repair has been controversial. The purpose of this study was to evaluate the functional and anatomic results after arthroscopic repair of large and massive rotator cuff tears with use of ultrasound as an imaging modality to determine the postoperative integrity of the repair. (More)
The ligands for programmed cell death 1 (PD-1), an immunoinhibitory receptor belonging to CD28/cytotoxic T lymphocyte antigen 4 family, are PD-1 ligand 1 and 2 (PD-Ls). Recent reports suggest that the aberrant expression of PD-Ls on tumor cells impairs antitumor immunity, resulting in the immune evasion of the tumor cells. Although an inverse correlation(More)
BACKGROUND Although many investigators have evaluated the accuracy of ultrasonography and magnetic resonance imaging for the detection of full and partial-thickness rotator cuff tears, few have directly compared the two tests. The purpose of our study was to compare the accuracy of the two tests for detection and measurement of the size of rotator cuff(More)
BACKGROUND Very little comparative information is available regarding the demographic and morphological characteristics of asymptomatic and symptomatic rotator cuff tears. This information is important to provide insight into the natural history of rotator cuff disease and to identify which factors may be important in the development of pain. The purpose of(More)
BACKGROUND Exosomes play a major role in cell-to-cell communication, targeting cells to transfer exosomal molecules including proteins, mRNAs, and microRNAs (miRNAs) by an endocytosis-like pathway. miRNAs are small noncoding RNA molecules on average 22 nucleotides in length that regulate numerous biological processes including cancer pathogenesis and(More)
PURPOSE Endometriotic cysts are known to transform into ovarian cancers, such as clear cell and endometrioid carcinomas. We hypothesized that an iron-rich environment produced by the repetition of hemorrhage in the endometriotic cysts during the reproductive period may play a crucial role in carcinogenesis in the cysts through the iron-induced persistent(More)
Recent molecular and pathological evidence suggests that endometriosis is a monoclonal, neoplastic disease. Moreover, endometriosis serves as a precursor of ovarian cancer (endometriosis-associated ovarian cancer; EAOC), especially of the endometrioid and clear cell subtypes. Although a variety of molecular events, such as p53 alteration, PTEN silencing,(More)
The purpose of this study was to evaluate the outcome after subcoracoid pectoralis major transfer for anterior-superior shoulder instability in massive rotator cuff insufficiency. Fourteen patients underwent subcoracoid pectoralis major transfer for this debilitating surgical complication. At a mean 17.5-month follow-up, there were 11 satisfactory and 3(More)
BACKGROUND Double-row arthroscopic rotator cuff repairs were developed to improve initial biomechanical strength of repairs to improve healing rates. Despite biomechanical improvements, failure of healing remains a clinical problem. PURPOSE To evaluate the anatomical results after double-row arthroscopic rotator cuff repair with ultrasound to determine(More)
BACKGROUND Proximal humeral migration is commonly seen in rotator-cuff-deficient shoulders. The specific effects of the size of the rotator cuff tear and of pain on glenohumeral kinematics have been poorly defined. The purpose of this study was to examine the influences of cuff tear size and pain, separately, on humeral migration in a series of patients(More)