Factors associated with long head of the biceps tendon tear severity and predictive insights for grade II tears in rotator cuff surgery.

BACKGROUND: In rotator cuff repair, the long head of the biceps tendon (LHB) is commonly used as graft material. However, factors influencing LHB tear severity are poorly understood, and predicting grade II LHB tears is challenging. This study aimed to identify these factors preoperatively. METHODS: The demographics, medical parameters, and pain severity of 750 patients who underwent arthroscopic surgery from January 2010 to February 2021 were evaluated to determine the factors associated with LHB tear severity and grade II tears. Both overall and largeto-massive rotator cuff tear (RCT) cohorts underwent ordinal and binary logistic regression analyses. Predictive accuracy for grade II LHB tears was determined using the area under the receiver operating characteristic curve (AUC). RESULTS: In the overall cohort, high-sensitivity C-reactive protein (hs-CRP) >1 mg/L (P<0.001), subscapularis tear (P<0.001), hypothyroidism (P=0.031), and the tangent sign (P=0.003) were significantly associated with LHB tear severity, and hs-CRP>1 mg/L, subscapularis tear, and Patte retraction degree were significantly associated with grade II LHB tears (P<0.001). In the large-to-massive RCT cohort, hs-CRP>1 mg/L, hypertension, and age ≥50 years (P<0.05) were significantly associated with LHB tear severity, and hs-CRP>1 mg/L (P<0.001) and hypertension (P=0.026) were significantly associated with grade II LHB tears. In both cohorts, hs-CRP >1 mg/L demonstrated good predictive accuracy for grade II LHB tears (AUCs: 0.72 and 0.70). CONCLUSIONS: Serum hs-CRP >1 mg/L is associated with LHB tear severity and serves as a reliable predictor of grade II LHB tears, facilitating preoperative assessment of the LHB as potential graft material in arthroscopic rotator cuff repair. Level of evidence: III.

Protective and Regenerative Effects of Reconstituted HDL on Human Rotator Cuff Fibroblasts under Hypoxia: An In Vitro Study.

Hypoxia and hypo-high-density lipoproteinemia (hypo-HDLemia) are proposed risk factors for rotator cuff tear. HDL is recognized for its potential benefits in ischemia-driven angiogenesis and wound healing. Nevertheless, research on the potential benefits of reconstituted HDL (rHDL) on human rotator cuff fibroblasts (RCFs) under hypoxia is limited. This study investigates the cytoprotective and regenerative effects of rHDL, as well as N-acetylcysteine (NAC), vitamin C (Vit C), and HDL on human RCFs under hypoxic conditions. Sixth-passage human RCFs were divided into normoxia, hypoxia, and hypoxia groups pretreated with antioxidants (NAC, Vit C, rHDL, HDL). Hypoxia was induced by 1000 µM CoCl2. In the hypoxia group compared to the normoxia group, there were significant increases in hypoxia-inducible factor-1α (HIF-1α), heme oxygenase-1 (HO-1), and Bcl-2/E1B-19kDa interacting protein 3 (BNIP3) expressions, along with reduced cell viability, elevated reactive oxygen species (ROS) production, apoptosis rate, expressions of cleaved caspase-3, cleaved poly ADP-ribose polymerase-1 (PARP-1), vascular endothelial growth factors (VEGF), and matrix metalloproteinase-2 (MMP-2), as well as decreased collagen I and III production, and markedly lower cell proliferative activity (p ≤ 0.039). These responses were significantly mitigated by pretreatment with rHDL (p ≤ 0.046). This study suggests that rHDL can enhance cell proliferation and collagen I and III production while reducing apoptosis in human RCFs under hypoxic conditions.

Associations of normal fasting glucose levels and of insulin resistance with degenerative rotator cuff tear : Normoglycemia and rotator cuff tear.

BACKGROUND: The upper normoglycemic range has been proposed as a risk factor for degenerative rotator cuff tendon tear (RCT), and insulin resistance has been suggested as a risk factor for tendinopathy. However, no research has established their association with degenerative RCT in the general population. This study aimed to determine whether fasting glucose levels and insulin resistance are risk factors for degenerative RCT in the normoglycemic population and identify the risk range for fasting glucose. METHODS: This study included 418 normoglycemic participants from a rural cohort. Participants completed questionnaires, physical exams, blood tests, and MRI evaluations of both shoulders. Insulin resistance was assessed using a triglyceride/high-density-lipoprotein (TG/HDL) ≥ 3.5. Logistic regression analysis was used to determine the association between fasting glucose level, TG/HDL ≥ 3.5, and other factors and degenerative RCT. The study calculated the areas under the receiver operating characteristic curve (AUC) to determine the more appropriate predicting value between the scale and categorical values of fasting glucose levels, and compared the AUCs using the DeLong method. RESULTS: In the multivariable analyses, both scale and categorical values of fasting glucose levels, and TG/HDL ≥ 3.5 were significantly associated with degenerative RCT. Fasting glucose levels ≥ 90.5 mg/dL (OR: 3.87, 95% CI: 2.10-7.06) in scale value and 90-99 mg/dL (OR: 4.13, 95% CI: 2.87-8.12) in categorical value were significantly associated with degenerative RCT (P < .001). The AUC of the scale value of fasting glucose levels ≥ 90.5 mg/dL was 0.68. The AUC of the categorical value of fasting glucose levels of 90-99 mg/dL was 0.70. Because of the significantly larger AUC of the categorical value of fasting glucose levels of 90-99 mg/dL, those fasting glucose levels were determined to be independently associated with degenerative RCT (P < .001). CONCLUSIONS: High fasting glucose levels within the normal range may link to increase insulin resistance and risk of degenerative RCT. Normoglycemic levels of 90-99 mg/dL and insulin resistance may be risk factors for degenerative RCT. LEVEL OF EVIDENCE: Level III, prognostic study.

Hint from an Enzymatic Reaction: Superoxide Dismutase Models Efficiently Suppress Colorectal Cancer Cell Proliferation.

Superoxide dismutases (SODs) are essential antioxidant enzymes that prevent massive superoxide radical production and thus protect cells from damage induced by free radicals. However, this concept has rarely been applied to directly impede the function of driver oncogenes, thus far. Here, leveraging efforts from SOD model complexes, we report the novel finding of biomimetic copper complexes that efficiently scavenge intracellularly generated free radicals and, thereby, directly access the core consequence of colorectal cancer suppression. We conceived four structurally different SOD-mimicking copper complexes that showed distinct disproportionation reaction rates of intracellular superoxide radical anions. By replenishing SOD models, we observed a dramatic reduction of intracellular reactive oxygen species (ROS) and adenine 5'-triphosphate (ATP) concentrations that led to cell cycle arrest at the G2/M stage and induced apoptosis in vitro and in vivo. Our results showcase how nature-mimicking models can be designed and fine-tuned to serve as a viable chemotherapeutic strategy for cancer treatment.

Risk factors of chronic subscapularis tendon tear.

BACKGROUND: Chronic subscapularis tendon tear (SBT) is a degenerative disease and a common pathologic cause of shoulder pain. Several potential risk factors for chronic SBT have been reported. Although metabolic abnormalities are common risk factors for degenerative disease, their potential etiological roles in chronic SBT remains unclear. The purpose of this study was to investigate potential risk factors for chronic SBT, with particular attention to metabolic factors. METHODS: This study evaluated single shoulders of 939 rural residents. Each subject undertook a questionnaire, physical examinations, blood tests, and simple radiographs and magnetic resonance imaging (MRI) evaluations of bilateral shoulders. Subscapularis tendon integrity was determined by MRI findings based on the thickness of the involved tendons. The association strengths of demographic, physical, social, and radiologic factors, comorbidities, severity of rotator cuff tear (RCT), and serologic parameters for SBT were evaluated using logistic regression analyses. The significance of those analyses was set at p<0.05. RESULTS: The prevalence of SBT was 32.2% (302/939). The prevalence of partial- and full-thickness tears was 23.5% (221/939) and 8.6% (81/939), respectively. The prevalence of isolated SBT was 20.2% (190/939), SBT combined with supraspinatus or infraspinatus tendon tear was 11.9% (112/939). In multivariable logistic regression analysis, dominant side involvement (p<0.001), manual labor (p=0.002), diabetes (p<0.001), metabolic syndrome (p<0.001), retraction degree of Patte tendon (p<0.001), posterosuperior RCT (p=0.010), and biceps tendon injury (p<0.001) were significantly associated with SBT. CONCLUSIONS: Metabolic syndrome is a potential risk factor for SBT, as are these factors: overuse activity, diabetes, posterosuperior RCT, increased retraction of posterosuperior rotator cuff tendon, and biceps tendon injury.

Prediction of Bilaterality in Patients With 1 Posterosuperior Rotator Cuff Tear.

BACKGROUND: In patients with a known unilateral posterosuperior rotator cuff tear (PSRCT), the ability to predict a contralateral PSRCT may assist in earlier diagnosis and improved patient outcomes. PURPOSE: To determine factors associated with bilateral PSRCT and their most predictive combinations using a nonhospitalized general population. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: This study involved 736 individuals (n = 1472 shoulders) drawn from a rural cohort. PSRCT was diagnosed using magnetic resonance imaging. Symptoms of the contralateral shoulder were not considered. The demographic, physical, social, metabolic, and imaging factors, as well as comorbidities, were evaluated using logistic regression analysis. Cutoff values for the significantly associated variables obtained from multivariable logistic regression analysis were calculated using the receiver operating characteristic (ROC) curve. The areas under the ROC curve (AUCs) of the combinations of significantly associated variables were compared using the DeLong method to determine the combination most predictive of bilateral PSRCT. The likelihood ratio and the posttest probability for each of the combinations were assessed. RESULTS: Age ≥61 years, manual labor, critical shoulder angle (CSA) ≥35°, retraction degree of Patte ≥ grade 2, biceps tendon injury, and metabolic syndrome were significantly associated with bilateral PSRCT in multivariable analysis (P < .001). The 1-by-1 combination of any 4 of the 6 associated factors significantly increased the AUC of any smaller combinations of those 6 factors (P < .001). The AUCs of the 4-somes were all similar (P ≥ .383) and were not significantly increased by further addition of identified associated factors (P ≥ .422). Any combination of 4 of the 6 associated factors was highly predictive of bilateral PSRCT, each having a minimum AUC of 0.70, a likelihood ratio of >10, and a minimum posttest probability of 80%. CONCLUSION: Unilateral PSRCT, accompanied by any 4 of the variables of age ≥61 years, manual labor, CSA ≥35°, retraction degree of Patte ≥ grade 2, biceps tendon injury, and metabolic syndrome, is highly predictive of PSRCT in the other shoulder.

Involvement of inflammatory lipoproteinemia with idiopathic adhesive capsulitis accompanying subclinical hypothyroidism.

BACKGROUND: Thyroid functional abnormalities are considered risk factors for idiopathic adhesive capsulitis (IAC) though that relationship remains uncertain. Although dyslipidemias are associated with IAC, no readily accessible study has reported associations between dyslipidemias and IAC patients with subclinical hypothyroidism. The purposes of this study were to investigate whether subclinical hypothyroidism is an independently associated factor for IAC and to determine the differences in prevalence of dyslipidemias between two groups of persons with subclinical hypothyroidism: one composed of IAC patients and the other of individuals without IAC. METHODS: This case-control study included a case group of 412 IAC patients without intrinsic shoulder lesions, extrinsic causes, or medication for thyroid dysfunction. The control group comprised 1236 age- and sex-matched persons seeking general checkups at the authors' health promotion center during the same period as the case group. Control subjects had normal shoulder function and no previously diagnosed adhesive capsulitis, no medication for thyroid dysfunction, and no history of trauma or of shoulder surgery. The studied variables were age, gender, obesity, diabetes, dyslipidemias, subclinical hypothyroidism, hypothyroidism, and hyperthyroidism. A conditional logistic regression analysis evaluated the matched sets of subjects to determine odds ratios and 95% confidence intervals for the studied variables. The differences in the prevalence of dyslipidemias between IAC patients with subclinical hypothyroidism and individuals with subclinical hypothyroidism but without IAC were determined with generalized estimating equations, using covariates of age, sex, and diabetes. The P values were set at < 0.05. RESULTS: Subclinical hypothyroidism (odds ratio, 2.10; 95% confidence interval, 1.36-3.15; P = .001) was significantly associated with IAC. Patients with IAC and subclinical hypothyroidism had a significantly higher prevalence of hyper-low-density lipoproteinemia, an inflammatory lipoproteinemia, than individuals with subclinical hypothyroidism but without IAC (P = .002). CONCLUSIONS: Subclinical hypothyroidism is significantly associated with IAC. Hyper-low-density lipoproteinemia, an inflammatory lipoproteinemia, is involved in IAC accompanied by subclinical hypothyroidism.

Factors Associated With Lateral Epicondylitis of the Elbow.

BACKGROUND: Metabolic factors have been linked to tendinopathies, yet few studies have investigated the association between metabolic factors and lateral epicondylitis. PURPOSE: To evaluate risk factors for lateral epicondylitis, including several metabolic factors. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: We evaluated 1 elbow in each of 937 volunteers from a rural region that employs many agricultural laborers. Each participant received a questionnaire, physical examinations, blood tests, simple radiographic evaluations of both elbows, magnetic resonance imaging of bilateral shoulders, and an electrophysiological study of bilateral upper extremities. Lateral epicondylitis was diagnosed using 3 criteria: (1) pain at the lateral aspect of the elbow, (2) point tenderness over the lateral epicondyle, and (3) pain during resistive wrist dorsiflexion with the elbow in full extension. Multivariable logistic regression analysis was used to calculate the odds ratios (ORs) and 95% CIs for various demographic, physical, and social factors, including age, sex, waist circumference, dominant-side involvement, smoking habit, alcohol intake, and participation in manual labor; the comorbidities of diabetes, hypertension, thyroid dysfunction, metabolic syndrome, ipsilateral biceps tendon injury, ipsilateral rotator cuff tear, and ipsilateral carpal tunnel syndrome; and the serologic parameters of serum lipid profile, glycosylated hemoglobin A1c, level of thyroid hormone, and high-sensitivity C-reactive protein. RESULTS: The prevalence of lateral epicondylitis was 26.1% (245/937 participants). According to the multivariable logistic regression analysis, female sex (OR, 2.47; 95% CI, 1.78-3.43), dominant-side involvement (OR, 3.21; 95% CI, 2.24-4.60), manual labor (OR, 2.25; 95% CI, 1.48-3.43), and ipsilateral rotator cuff tear (OR, 2.77; 95% CI, 1.96-3.91) were significantly associated with lateral epicondylitis (P < .001 for all). No metabolic factors were significantly associated with lateral epicondylitis. CONCLUSION: Female sex, dominant-side involvement, manual labor, and ipsilateral rotator cuff tear were found to be risk factors for lateral epicondylitis. The study results suggest that overuse activity is more strongly associated with lateral epicondylitis than are metabolic factors.

Need for early exploration of radial nerve in humeral shaft fractures with radial nerve palsy.

INTRODUCTION: Radial nerve palsy (RNP) associated with humeral shaft fracture (HSF) is the most common nerve complication in long bone fractures. There is still controversy over the need for immediate exploration of the radial nerve (RN) in HSF with RNP. The purpose of the current study was to determine which situations of HSF with RNP require early exploration of the RN. MATERIALS AND METHODS: This is a retrospective study that included 55 patients who had visited the emergency department of the current authors' hospital and had been diagnosed with HSF between March of 2005 and September of 2015. Of these 55 patients, 14 (25.4%) had been diagnosed with HSF with RNP. We reviewed the medical records of those 14 patients and their radiographs to evaluate each fracture's type, location, pattern, energy of trauma, status of RN injury, and time until recovery from RNP. RESULT: All the 14 RNP patients had suffered high-energy trauma. Three had fractures in the proximal third (21.4%), six in the middle third (42.9%), and five in the distal third (35.7%). The three patients (21.4%) with incomplete recovery of RNP all had proximal third fractures; two of these three patients had RN transection. CONCLUSION: Early exploration of the radial nerve should be considered in patients with radial nerve palsy associated with proximal third humeral shaft fracture, regardless of the fracture patterns caused by the high-energy trauma.

Are any radiologic parameters independently associated with degenerative postero-superior rotator cuff tears?

BACKGROUND: Several radiologic parameters representing scapular morphology have been proposed as risk factors for degenerative posterosuperior rotator cuff tear (PSRCT). The causes of PSRCT are multifactorial; many reported risk factors are compound entities. However, no determination, made after adjustment with previously reported risk factors, of which radiologic parameters are independent risk factors for degenerative PSRCT, has been reported. Therefore, this study's purpose was to determine which radiologic parameters representing scapular morphology are independent risk factors for degenerative PSRCT in a general population after adjustment with previously suggested risk factors. METHODS: This study involved 629 subjects (629 shoulders) drawn from a cohort of rural residents. PSRCT diagnoses were based on magnetic resonance imaging findings. Logistic regression analysis was used to determine the odds ratios and 95% confidence intervals for the following variables: sex, age, height, weight, waist circumference, dominant-side involvement, smoking, alcohol consumption, manual labor, diabetes, hypertension, metabolic syndrome, thyroid dysfunction, serum lipid profile, high-sensitivity C-reactive protein, and radiologic parameters. The evaluated radiologic parameters were the superior displacement of the humeral head (SDHH) and those representing the scapular morphology. The radiologic parameters representing the scapular morphology were lateral acromial angle, acromial slope, acromial tilt, acromial index, and critical shoulder angle (CSA). Univariate logistic regression analyses for all variables, as well as multivariable logistic regression analyses for variables with significant associations and clinical effect sizes in the univariate logistic regression analyses, were performed. In order to determine the cutoff value for significant radiologic parameters, each pair of candidate cutoff values was obtained as follows: 1 candidate, as the lowest significant ordinal value in a univariate analysis, and the other candidate, according to a receiver operating characteristic curve analysis. Then, the cutoff values were determined by selecting the value in each candidate pair that had the larger area under the receiver operating characteristic curve, using the DeLong test. RESULTS: In the multivariable analyses, CSA was significantly associated with degenerative PSRCT after controlling for the following factors: age, waist circumference, dominant-side involvement, manual labor, diabetes, metabolic syndrome, hypo-high-density lipoproteinemia, and SDHH (P ≤ .033). CSA (odds ratio, 1.58 [95% confidence interval, 1.45-1.72]; P < .001) was the only significantly associated radiologic parameter among the studied radiologic parameters representing scapular morphology. CONCLUSION: CSA (≥35°) is an independent associated factor for degenerative PSRCT after adjustment for the following suggested risk factors: age, waist circumference, dominant-side involvement, manual labor, diabetes, metabolic syndrome, hypo-high-density lipoproteinemia, and SDHH.

Association between fasting glucose levels and adhesive capsulitis in a normoglycemic population: a case-control study.

BACKGROUND: Hyperglycemia is the most commonly cited risk factor for adhesive capsulitis. However, no study has established whether fasting glucose levels within the normoglycemic range are associated with idiopathic adhesive capsulitis (IAC). This study hypothesized that increments of fasting glucose levels within the normoglycemic range would be linked to IAC. This study investigated any association between normoglycemic fasting glucose levels and IAC. METHODS: This case-control study comprised a group of 151 patients with IAC without intrinsic shoulder lesions, extrinsic causes, or known metabolic risk factors such as diabetes, dyslipidemia, and thyroid dysfunction. The control group comprised 453 age- and sex-matched persons seeking general check-ups at the authors' health promotion center during the same period as the case group. Control subjects had normal shoulder function, no previous diagnosis of adhesive capsulitis or of metabolic disease, and no history of trauma or of shoulder surgery. The studied variables were body mass index, serum lipid profiles, thyroid hormone levels, fasting glucose levels, glycosylated hemoglobin A1c, and high-sensitivity C-reactive protein. Fasting glucose levels were studied as scale data and categorical data (<85, 85-89, 90-94, and 95-99 mg/dL). Multivariable conditional logistic regression analysis evaluated the matched sets of subjects. Odds ratios and 95% confidence intervals were determined for various potentially associated factors. RESULTS: Fasting glucose level, hypercholesterolemia, and high-sensitivity C-reactive protein were significantly associated with IAC (P ≤ .030). Fasting glucose levels in the <85 mg/dL quartile were significantly negatively associated with IAC (P ≤ .001). In contrast, fasting glucose levels in the 90-94 mg/dL quartile or higher were significantly positively associated with IAC (P ≤ .034). CONCLUSION: IAC is positively associated with fasting glucose levels of 90-99 mg/dL, which are currently considered normoglycemic.

Association Between High-Sensitivity C-Reactive Protein and Idiopathic Adhesive Capsulitis.

BACKGROUND: Chronic inflammation is implicated in the development of idiopathic adhesive capsulitis (IAC), whose association with high-sensitivity C-reactive protein (CRP), an inflammation marker, is undetermined. This study's purposes were to investigate the association between high-sensitivity CRP levels and IAC and to determine the metabolic factors associated with high-sensitivity CRP. METHODS: This case-control study examined a group of 202 patients with IAC and without intrinsic shoulder lesions or extrinsic causes and a control group of 606 age and sex-matched persons seeking general check-ups at our health promotion center during the same period as the case group. Control subjects had normal shoulder function and no previously diagnosed adhesive capsulitis; no medication for diabetes, dyslipidemia, and thyroid abnormalities; and no history of trauma or of shoulder surgery. The studied variables were body mass index; diabetes; thyroid abnormalities; dyslipidemias; triglyceride/high-density lipoprotein (TG/HDL) >3.5; serum levels of thyroid hormone, fasting glucose, and glycosylated hemoglobin A1c (HbA1c); and high-sensitivity CRP >1.0 mg/L. Multivariable conditional logistic regression analysis evaluated the matched sets of subjects. Odds ratios (ORs) and 95% confidence intervals (CIs) were determined for the studied variables possibly affecting IAC. RESULTS: Serum high-sensitivity CRP >1.0 mg/L was significantly associated with IAC (OR, 2.47 [95% CI, 1.65 to 3.70]) after adjusting for diabetes, fasting glucose level, HbA1c, dyslipidemia, TG/HDL >3.5, and thyroid-stimulating hormone (p ≤ 0.031). Diabetes (OR, 1.71 [95% CI, 1.09 to 3.33]), fasting glucose level (OR, 1.54 [95% CI, 1.12 to 2.12]), HbA1c (OR, 2.00 [95% CI, 1.25 to 3.22]), hypertriglyceridemia (OR, 1.70 [95% CI, 1.03 to 3.41]), hypo-high-density lipoproteinemia (OR, 1.98 [95% CI, 1.04 to 3.79]), and TG/HDL >3.5 (OR, 1.37 [95% CI, 1.06 to 1.88]) were significantly associated with high-sensitivity CRP >1.0 mg/L in patients with IAC (p ≤ 0.039). CONCLUSIONS: Serum high-sensitivity CRP >1.0 mg/L is an independent associated marker for IAC. Dyslipidemia, insulin resistance, and hyperglycemia, which are recognized factors associated with IAC, are also associated with high-sensitivity CRP >1.0 mg/L in these patients, supporting the interaction of chronic systemic inflammation in IAC. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Hypo-High-Density Lipoproteinemia Is Associated With Preoperative Tear Size and With Postoperative Retear in Large to Massive Rotator Cuff Tears.

PURPOSE: To evaluate any association of specific subtypes of dyslipidemia with increments of preoperative tear size and with structural integrity after arthroscopic rotator cuff repair (ARCR). METHODS: One surgeon's consecutive patients who underwent ARCR from January 2011 to June 2018 were reviewed. The inclusion criteria were minimum 1-year follow-up ultrasonography, blood tests, physical examination, and provision of informed consent. The exclusion criteria were incomplete laboratory tests, history of acute trauma, previous shoulder surgery, isolated subscapularis tendon tear, inappropriate radiographs, no 1-year follow-up ultrasonography, and medication with lipid-lowering drugs. Associated preoperative factors for the increments of tear size and for retear after ARCR were determined using logistic regression analysis. Statistical significance was set at P < .05. RESULTS: Of the 502 ARCR patients from the study period, 195 patients (195 shoulders), with a mean age of 60.5 ± 7.5 years, met the inclusion and exclusion criteria. Age (odds ratio [OR], 1.2; 95% confidence interval [CI], 1.1-1.3), diabetes (OR, 3.6; 95% CI, 1.7-7.5), and hypo-high-density lipoproteinemia (hypo-HDLemia) (OR, 2.9; 95% CI, 1.5-5.6) were significantly associated with increments of preoperative tear size (P ≤ .01). Diabetes (OR, 3.0; 95% CI, 1.3-6.6), critical shoulder angle (OR, 2.0; 95% CI, 1.4-3.0), and tear size (OR, 2.1; 95% CI, 1.3-3.4) were significantly associated with retear after ARCR in overall study subjects (P = .01). Diabetes (OR, 3.8; 95% CI, 1.3-11.4), hypo-HDLemia (OR, 3.0; 95% CI, 1.1-8.8), and critical shoulder angle (OR, 1.5; 95% CI, 1.1-2.3) had significant associations with retear after ARCR in patients with a large to massive preoperative tear size (P ≤ .04). CONCLUSIONS: Preoperative hypo-HDLemia (high-density lipoprotein level < 40 mg/dL in male patients and < 50 mg/dL in female patients) has a significant association with the increments of preoperative tear size and with retear after ARCR in large- to massive-sized rotator cuff tears. LEVEL OF EVIDENCE: Level IV, case series.

Metabolic and inflammatory links to rotator cuff tear in hand osteoarthritis: A cross sectional study.

OBJECTIVES: To estimate the prevalence and associated factors of rotator cuff tear (RCT) in patients with hand osteoarthritis (HOA). METHODS: Between June 2013 and December 2015, we recruited 1150 participants in rural area of South Korea. Of the 1150 participants, 307 participants with HOA were analyzed. Plain radiography of both hands, magnetic resonance imaging of both shoulders, and serum levels of high-sensitive C-reactive protein (hsCRP) and high-density lipoprotein (HDL) were obtained for all patients. HOA and RCT were diagnosed by clinical and radiologic findings. RESULTS: The prevalence of RCT in patients with HOA (192/307, 62.5%) was higher than that in those without HOA (410/827, 49.5%, p<0.001). Among the 307 patients with HOA, the patients with RCT were older, and had higher hsCRP and lower HDL levels than the patients without RCT. Multiple logistic regression analysis confirmed significant associations of age (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.02-1.11), serum hsCRP levels ≥0.6mg/L (OR, 1.68; CI, 1.00-2.80), and low HDL levels (male, <50 mg/dL; female, <40 mg/dL) (OR, 1.93; CI, 1.05-3.56) with RCT in patients with HOA. For patients below 60 years old, the prevalence of RCT was 2.8-fold higher in the low HDL group than normal HDL group (p = 0.048). Finally, the prevalence of RCT was 2.6-fold higher in patients with HOA with both elevated hsCRP and low HDL levels compared with those with neither (p<0.05). CONCLUSIONS: Our findings suggest inflammation and metabolic factors were associated with the prevalence of RCT in HOA patients.

In vitro effects of alendronate on fibroblasts of the human rotator cuff tendon.

BACKGROUND: Bone mineral density of the humeral head is an independent determining factor for postoperative rotator cuff tendon healing. Bisphosphonates, which are commonly used to treat osteoporosis, have raised concerns regarding their relationships to osteonecrosis of the jaw and to atypical fracture of the femur. In view of the prevalence of rotator cuff tear in osteoporotic elderly people, it is important to determine whether bisphosphonates affect rotator cuff tendon healing. However, no studies have investigated bisphosphonates' cytotoxicity to human rotator cuff tendon fibroblasts (HRFs) or bisphosphonates' effects on rotator cuff tendon healing. The purpose of this study was to evaluate the cytotoxicity of alendronate (Ald), a bisphosphonate, and its effects on HRF wound healing. METHODS: HRFs were obtained from human supraspinatus tendons, using primary cell cultures. The experimental groups were control, 0.1 µM Ald, 1 µM Ald, 10 µM Ald, and 100 µM Ald. Alendronate exposure was for 48 h, except during a cell viability analysis with durations from 1 day to 6 days. The experimental groups were evaluated for cell viability, cell cycle and cell proliferation, type of cell death, caspase activity, and wound-healing ability. RESULTS: The following findings regarding the 100 µM Ald group contrasted with those for all the other experimental groups: a significantly lower rate of live cells (p < 0.01), a higher rate of subG1 population, a lower rate of Ki-67 positive cells, higher rates of apoptosis and necrosis, a higher number of cells with DNA fragmentation, higher caspase-3/7 activity (p < 0.001), and a higher number of caspase-3 positive staining cells. In scratch-wound healing analyses of all the experimental groups, all the wounds healed within 48 h, except in the 100 µM Ald group (p < 0.001). CONCLUSIONS: Low concentrations of alendronate appear to have little effect on HRF viability, proliferation, migration, and wound healing. However, high concentrations are significantly cytotoxic, impairing cellular proliferation, cellular migration, and wound healing in vitro.

Association of high sensitivity C-reactive protein with tearing of the long head of the biceps tendon.

BACKGROUND: This study proposed to investigate whether high-sensitivity C-reactive protein (hs-CRP) is an independent risk factor for long head of biceps tendon (LHBT) tear and whether hs-CRP can increase accuracy in diagnosing LHBT tear. METHODS: This study involved 582 shoulders of 557 consecutive patients who received arthroscopic examinations at the authors' institution between January 2010 and July 2018. The strengths of associations between LHBT tear and various factors were determined by calculating the odds ratios (ORs), with 95% confidence intervals (CIs), using logistic regression analyses. The studied variables were demographic, physical, social, metabolic, comorbidity, hs-CRP, and pain on a visual analog scale (VAS) factors, as well as those related to rotator cuff tear (RCT). Significant factors in the multivariable logistic analysis were evaluated to determine their diagnostic values, including their likelihood ratios and post-test probabilities for LHBT tear. RESULTS: In the multivariable analysis, five variables were significant: age, retraction degree of Patte, subscapularis tendon tear, hs-CRP > 1 mg/L, and pain VAS (p ≤ 0.01). The best combination of determinations for diagnosing LHBT tear, which yielded a strong positive likelihood ratio of 19.07 and a high post-test probability of 96%, was age ≥ 67 years, subscapularis tendon tear, grade of Patte ≥2, hs-CRP > 1, and pain VAS ≥ 7. CONCLUSIONS: Serum hs-CRP > 1 mg/L is an independent risk factor for LHBT tear, along with the expected risk factors of age, subscapularis tendon tear, retraction degree of Patte, and pain VAS. Serum hs-CRP > 1 mg/L increases the diagnostic accuracy for LHBT tear. LEVEL OF EVIDENCE: Level IV, Clinical case series.

A Modified Weaver-Dunn Procedure with or without Chip Bone Graft for the Treatment of Acromioclavicular Joint Separation.

BACKGROUND: In spite of frequent injuries to the acromioclavicular (AC) joint, there is no consensus regarding optimal technique to be used. This cohort study evaluated the clinical results of a modified Weaver-Dunn procedure with or without chip bone graft for the treatment of AC joint separation retrospectively. MATERIALS AND METHODS: 60 consecutive patients with AC joint separation, between the age of 19-76 years (mean age 43 years), were enrolled between January 2005 and September 2011. Forty patients (35 men, 5 women) were treated with a modified Weaver-Dunn procedure, and did not receive bone graft during the procedure (Group 1), whereas twenty patients (19 men, 1 woman) received autogenous chip bone graft (Group 2). Stability of the AC joint was evaluated clinically and radiographically, and the clinical results were assessed by the Imatani evaluation system. RESULTS: The mean duration of followup was 2 years and 2 months. The results were excellent in all patients except one. At final followup, roentgenographic measurement revealed that the mean coracoclavicular interval was 8.2 mm on the affected side, and 8.9 mm on the unaffected side in Group 1, and 9.5 mm on the affected side and 10.1 mm on the unaffected side in Group 2. For Group 1, there were significant differences between augmentation of the grafted coracoacromial (CA) ligament antero-posteriorly and laterally (Option B) and repair of the torn AC ligament with augmentation of the grafted CA ligament antero-inferiorly (option A; P = 0.0351). CONCLUSIONS: The modified Weaver-Dunn procedure (Group 1 and 2) provides a stable and strong reconstruction for the treatment of AC joint separation. In addition, this modified Weaver-Dunn procedure with chip bone graft (Group 2) may lead to same or more secure healing of the grafted CA ligament-bone than the same procedure without chip bone graft (P = 0.9737).

Association between the location of tuberosity cysts and rotator cuff tears: A comparative study using radiograph and MRI.

BACKGROUND: The association between tuberosity cysts and rotator cuff tears (RCTs) and the nature of the major contributing factors to tuberosity cyst formation continue to be controversial. The purpose of our study was to evaluate the strength of associations of RCT and various factors involved in the chronicity of RCT with tuberosity cysts, using magnetic resonance imaging (MRI) and radiographs. METHODS: We reviewed consecutive patients with various disease entities between August 2004 and July 2013. After excluding unsuitable patients, this study involved 1007 shoulders of 906 consecutive patients. Each tuberosity cyst was categorized as an anterior greater tuberosity (GT), posterior GT, lesser tuberosity, and bare-area cyst. The odds ratios (ORs) and 95% confidence intervals (CIs) between the tuberosity cysts and various factors were evaluated by logistic regression analyses; p-value was set below 0.05. RESULTS: Anterior GT cysts and posterior GT cysts on MRI or anterior GT cysts on radiographs were significantly associated with supraspinatus tendon (SST) tears ( p ≤ 0.019) and infraspinatus tendon (IST) tears ( p ≤ 0.004). Among the shoulder pathologies, RCTs only significantly associated with cyst formation (OR 4.23, 95% CI 3.17-5.65; p < 0.001). The retraction grade of Patte was significantly associated with anterior GT cyst (OR 3.65, 95% CI 2.42-5.48; p < 0.001). CONCLUSION: Detecting an anterior GT cyst in a radiograph, even a low prevalence, in a patient with symptomatic shoulder indicates a need to consider RCT, especially of the SST, IST, and a high possibility of a retracted tear.