Are functional outcomes and reoperation rates really better than those of cementless stems in displaced femoral neck fractures? An updated systematic review and meta-analysis of randomized controlled trials in current-generation stem designs.

BACKGROUND: The aim of the study was to conduct a systematic review and meta-analysis to compare the functional outcomes and reoperation rates of cemented and cementless hip arthroplasty for treating displaced femoral neck fractures in elderly patients. METHODS: Systematic searches were conducted of literature up to December 2018 on PubMed, Embase, Cochrane, and Web of Science for randomized controlled trials (RCTs) concerning current-generation stem designs only. Two reviewers independently determined eligibility, extracted the outcome data and assessed the risk of bias of eligible studies. The follow-up data and complication rates were pooled by using random-effects models and fixed-effects models, with mean differences and risk ratios for continuous and dichotomous variables, respectively. RESULTS: Eight RCTs involving 1361 patients (1361 hips) were included in the meta-analysis. Cemented stems were associated with fewer implant-related complications (odds ratio [OR] = 0.303; 95% confidence interval [CI], 0.185%-0.496%; p < 0.001) and reoperations (OR = 0.492; 95% CI, 0.247%-0.977%; p = 0.043). There were no statistically significant differences between groups in functional outcomes, including those assessed by the EuroQol(EQ)-5D and Harris Hip Score, mortality rates, major systemic complications, minor local complications, operation times, intraoperative blood losses, and lengths of hospital stays. CONCLUSION: In treating displaced femoral neck fracture in elderly patients with hip arthroplasty with current-generation stems, cemented stems were found to have fewer implant-related complications and reoperations than those of cementless stems. Functional outcomes and mortality rates were similar between the groups.

The rein-type arthroscopic capsular suture for triangular fibrocartilage complex foveal tears: midterm results for 90 patients.

We describe an arthroscopic rein-type capsular suture that approximates the triangular fibrocartilage complex to the anatomical footprint, and report the results at a minimum 12 month follow-up. The procedure involves two 3-0 polydioxanone horizontal mattress sutures inserted 1.5 cm proximal to the 6-R and 6-U portals to obtain purchase on the dorsal and anterior radioulnar ligaments, respectively. The two sutures work as a rein to approximate the triangular fibrocartilage complex to the fovea. Ninety patients with Type IB triangular fibrocartilage complex injuries were included retrospectively. The 12-month postoperative Modified Mayo Wrist scores, Disabilities of Arm, Shoulder and Hand scores and visual analogue scale for pain showed significant improvements on preoperative values. Postoperative range of wrist motion, grip strength and ultrasound assessment of the distal radioulnar joint stability were comparable with the normal wrist. The patients had high satisfaction scores for surgery. There were minor complications of knot irritation. No revision surgery for distal radioulnar joint instability was required. It is an effective and technically simple procedure that provides a foveal footprint contact for the triangular fibrocartilage complex.Level of evidence: IV.

The efficacy of periarticular injection intraoperatively for mini-open rotator cuff repair: A comparative study.

BACKGROUND: The optimal postoperative analgesia after open rotator cuff repair surgery remains unclear. This study compared the use of a multimodal pain regimen including periarticular injection (PAI), with a control condition. We hypothesized that PAI leads to decreased opioid consumption and lower pain scores. METHODS: The perioperative analgesic regimen was standardized and implemented from January 1, 2017 to December 31, 2017. The PAI was administered from July 1, 2017 to December 31, 2017. The historical control group was enrolled from January 1, 2017 to June 30, 2017. The evaluation items included assessments of pain using a 10-point visual analog scale (VAS) before and after the mini-open rotator cuff repair and on postoperative days 1, 2, and 3. The dose of ketorolac suppository and its side effects were also evaluated. RESULTS: The VAS score on the day of the operation was significantly low in the PAI group and less incidence of night pain. The time point of the rescue drug was longer in the PAI group than the control group (12.7 hours vs. 0.62 hours; p < 0.01). No cardiac or central nervous system toxicity was observed. DISCUSSION: In our study, PAI in the shoulder after mini-open rotator cuff repair showed effective pain control on the day of the surgery, postponed the time of the first dosage of intravenous pain medication, and reduced the total dosage of the intravenous pain medication.

Surgical outcome of upper extremity fractures in patients with Parkinson's disease.

Patients with Idiopathic Parkinson's Disease (PD) have an increased risk for fractures. Currently, many studies have reported inferior outcomes in PD patients after orthopedic procedures. However, there are very few studies assessing the outcome of upper extremity fractures (UEF) in PD patients. In this study, we reviewed 40 patients with PD that received surgical intervention for an UEF. We retrospectively reviewed patients with PD that received surgical fixation for an UEF at a tertiary trauma center. The primary objective was to determine the treatment failure rate after surgical fixation. The secondary outcomes include mode of failure, time to treatment failure, length of hospital stay, readmission rate, reoperation rate, and postoperative complications. A total of 40 patients with PD (42 fractures) underwent surgery. The most common fracture type was radius fracture (n = 19), followed by humerus fracture (n = 15), metacarpal/phalangeal fracture (n = 5), clavicle fracture (n = 2) and olecranon fracture (n = 1). The overall treatment failure rate was 40.5% (n = 17). The time to treatment failure was 1.24 ± 3.1 months and length of hospital stay was 6 ± 3.9 days, the readmission rate within 30 days was 14% (n = 6), and reoperation rate was 14% (n = 6). The complication rate was 16.6% (n = 7) and patients with humeral fractures appeared to have the longest hospital stays (6.6 days) and increased complication rates (13%, n = 2). Patients with PD have high treatment failure rates despite surgical fixation of an UEF. These patients often have a frail status with multiple comorbidities which may complicate their postoperative course.Level of evidence level 4 case series.

Ganoderma microsporum immunomodulatory protein, GMI, promotes C2C12 myoblast differentiation in vitro via upregulation of Tid1 and STAT3 acetylation.

Ageing and chronic diseases lead to muscle loss and impair the regeneration of skeletal muscle. Thus, it's crucial to seek for effective intervention to improve the muscle regeneration. Tid1, a mitochondrial co-chaperone, is important to maintain mitochondrial membrane potential and ATP synthesis. Previously, we demonstrated that mice with skeletal muscular specific Tid1 deficiency displayed muscular dystrophy and postnatal lethality. Tid1 can interact with STAT3 protein, which also plays an important role during myogenesis. In this study, we used GMI, immunomodulatory protein of Ganoderma microsporum, as an inducer in C2C12 myoblast differentiation. We observed that GMI pretreatment promoted the myogenic differentiation of C2C12 myoblasts. We also showed that the upregulation of mitochondria protein Tid1 with the GMI pre-treatment promoted myogenic differentiation ability of C2C12 cells. Strikingly, we observed the concomitant elevation of STAT3 acetylation (Ac-STAT3) during C2C12 myogenesis. Our study suggests that GMI promotes the myogenic differentiation through the activation of Tid1 and Ac-STAT3.

Long-term results in the patients with traumatic hip fracture-dislocation: Important prognostic factors.

BACKGROUND: Traumatic hip dislocation with or without acetabular fractures can lead to various outcomes of the hip. Long-term follow-up studies on traumatic hip dislocation are few. We conducted a retrospective study of the treatment and long-term outcomes in patients with hip dislocation to determine prognostic factors. METHODS: From 2001 to 2016, we enrolled 38 patients in our study. All the patients had been diagnosed through radiography or computed tomography. Emergent closed reduction was performed initially. We hypothesized that poor outcomes, including osteonecrosis and traumatic osteoarthritis, are related to specific factors. RESULTS: All the patients had posterior dislocation initially. Closed reduction or open reduction due to irreducible after closed reduction was performed within 6 hours of dislocation in most patients. In total, nine patients had poor outcomes of the hip, including osteonecrosis and traumatic osteoarthritis and total hip arthroplasty. Specific factors that lead to poor outcomes were patient age and timing of reduction. CONCLUSION: Although end results in severe traumatic hip dislocation are disappointing, conservatism in applying the secondary reconstructive procedure is desirable. In our series, crucial factors for long-term prognosis were patient age and timing of hip reduction.

Combinatorial Low Dose Arsenic Trioxide and Cisplatin Exacerbates Autophagy via AMPK/STAT3 Signaling on Targeting Head and Neck Cancer Initiating Cells.

Head and neck squamous cell carcinoma (HNSCC) is a highly lethal disease with high-level of epidemic both in the world and Taiwan. Previous studies support that head and neck cancer-initiating cells (HN-CICs), a subpopulation of cancer cells with enhanced stemness properties, contribute to therapy resistance and tumor recurrence. Arsenic trioxide (As2O3; ATO) has shown to be an effective anti-cancer drug targeting acute promyelocytic leukemia (APL). Combinatorial treatment with high dose of ATO and cisplatin (CDDP) exert synergistic apoptotic effects in cancer cell lines of various solid tumors, however, it may cause of significant side effect to the patients. Nevertheless, none has reported the anti-cancerous effect of ATO/CDDP targeting HN-CICs. In this study, we aim to evaluate the low dose combination of ATO with conventional chemo-drugs CDDP treatment on targeting HN-CICs. We first analyzed the inhibitory tumorigenicity of co-treatment with ATO and chemo-drugs on HN-CICs which are enriched from HNSCC cells. We observed that ATO/CDDP therapeutic regimen successfully synergized the cell death on HN-CICs with a Combination Index (CI) <1 by Chou-Talalay's analysis in vitro. Interestingly, the ATO/CDDP regimen also induced exaggerated autophagy on HN-CICs. Additionally, this drug combination strategy also empowered both preventive and therapeutic effect by in vivo xenograft assays. Finally, we provide the underlying molecular mechanisms of ATO-based therapeutic regimen on HN-CICs. Together, low dose of combinatorial ATO/CDDP regimen induced cell death as well as exacerbated autophagy via AMPK-STAT3 mediated pathway in HN-CICs.

The outcome for surgical fixation of distal radial fractures in patients with idiopathic Parkinson's disease: a cohort study.

INTRODUCTION: Idiopathic Parkinson's disease (PD) is a progressive neurologic disorder causing postural instability and unsteady gait. These patients are at increased risk for fractures and have inferior outcomes after treatment. Several studies have evaluated the incidence and outcome of PD patients after hip fractures. However, there are limited studies assessing the outcome of upper extremity fractures in these patients. In this study, we evaluated the outcome of PD patients that received surgical intervention for distal radial fractures (DRF). We hypothesize that these patients have an inferior outcome after surgery in comparison with non-PD patients. METHODS: Between May 2005 and May 2017, we retrospectively reviewed all of the patients with DRF and subsequently underwent open reduction and internal fixation (ORIF) at a level 1 trauma center. All of the surgeries were performed by fellowship-trained orthopedic surgeons. The inclusion criteria include patients with a definitive diagnosis of PD, non-pathological DRF, and a minimum follow-up of 1 year or up until the time of treatment failure was noted. Each PD patient was matched for age and gender to 3 non-PD patients. The primary objective was to determine the failure rate after surgical fixation for DRF. The secondary outcomes include time to treatment failure, reoperation rate, readmission rate, length of hospital stay, and postoperative complications. RESULTS: A total of 88 patients were included in this study (23 PD, 65 non-PD patients). All underwent ORIF and received standard postoperative follow-ups. The overall treatment failure rate in PD was 39.1% vs. 4.6% in the non-PD group (p < 0.05). The time to treatment failure were 9.11 ± 3.86 weeks and 14.67 ± 5.8 weeks for PD and non-PD, respectively (p < 0.05). PD patients had a significantly higher rate of failure when k-wires and ESF were used (p < 0.05%), while loss of reduction was the most common mode of failure in PD (44.4%). The length of hospital stay for PD was 5.3 ± 4.69 days compared with 3.78 ± 0.96 days for non-PD (p = 0.01). There were 3 PD patients readmitted within 30 days after surgery, and 1 patient had pneumonia after the surgery. CONCLUSION: This study revealed that patients with PD have a high treatment failure rate despite surgical intervention for DRF. PD patients had a longer hospital stay and had a shorter time to treatment failure. In treating PD patients complicated with DRF, the surgeon must take into consideration the complex disease course of PD and the associated comorbidities such as osteoporosis, frail status, and frequent falls. Rehabilitation and disposition plans should be discussed in advance and longer hospital stays should be expected. Level of evidenceLevel IV, retrospective cohort study.

Association between Cervical Spondylosis and Migraine: A Nationwide Retrospective Cohort Study.

Background: Few studies have investigated the longitudinal association between cervical spondylosis (CS) and migraine by using a nationwide population-based database. Methods: We conducted a retrospective cohort study from 2000 to 2011 identifying 27,930 cases of cervical spondylosis and 111,720 control subjects (those without cervical spondylosis) from a single database. The subjects were frequency-matched on the basis of sex, age, and diagnosis date. The non- cervical spondylosis cohort was four times the size of the cervical spondylosis cohort. To quantify the effects of cervical spondylosis on the risk of migraine, univariate and multivariate Cox proportional hazard regression analyses were used to calculate the hazard ratio (HR), and 95% confidence interval (CI). Results: After a 10-year follow-up controlling for potential confounding factors, overall migraine incidence was higher in the cervical spondylosis cohort than in the non-cervical spondylosis cohort (5.16 and 2.09 per 1000 people per year, respectively; crude hazard ratio = 2.48, 95% confidence interval = 2.28-2.69), with an adjusted hazard ratio of 2.03 (95% confidence interval = 1.86-2.22) after accounting for sex, age, comorbidities, and medication. Individuals with myelopathy in the cervical spondylosis cohort had a 2.19 times (95% confidence interval = 1.80-2.66) higher incidence of migraine when compared than did those in the non- cervical spondylosis cohort. Conclusions: Individuals with cervical spondylosis exhibited a higher risk of migraine than those without cervical spondylosis. The migraine incidence rate was even higher among individuals with cervical spondylotic myelopathy.

Short-term Versus Long-term Outcomes After Open or Percutaneous Release for Trigger Thumb.

Good outcomes have been reported after both open and percutaneous surgery to release trigger thumb. This study evaluated short-term and long-term outcomes after treatment of trigger thumb with open or percutaneous release. A total of 126 trigger thumbs in 107 patients were reviewed from 2009 to 2012. Short-term (3 months) and long-term results (2 years) and complications of open release (58 digits) and percutaneous release (68 digits) were recorded and compared. Short-term complications included pain occurring in 9 digits (15.5%) in the open release group and in 2 digits (2.9%) in the percutaneous release group and scarring in 4 digits (6.9%) only in the open release group. Long-term complications included pain in 13 digits (19.1%) in the percutaneous release group and in 4 digits (6.9%) in the open release group; in addition, recurrent triggering occurred in 6 digits (8.8%) in the percutaneous release group and in 2 digits (3.4%) in the open release group. Pain and patient satisfaction were significantly better in the percutaneous release group in the short term, but they were better in the open release group in the long term. Although percutaneous release for trigger thumb is a safe and quick procedure, with good short-term outcomes, open release may provide better long-term outcomes. [Orthopedics. 2017; 40(1):e131-e135.].

Lunocapitate fusion with scaphoid excision for the treatment of scaphoid nonunion advanced collapse or scapho-lunate advanced collapse wrist.

BACKGROUND: Four-corner fusion is an effective procedure to treat advanced degenerative osteoarthritis of scaphoid nonunion advanced collapse or scapho-lunate advanced collapse wrists. However, lunocapitate fusion, an alternative procedure, shows benefits including less dissection of the soft tissue and also a shorter operation time. We reviewed 10 cases to reveal the complication rates and clinical outcomes of this procedure. METHODS: We retrospectively reviewed 10 patients with symptomatic scaphoid nonunion advanced collapse or scapho-lunate advanced collapse wrists who had received lunocapitate fusion with scaphoid excision. The average follow-up period was 44.5 months (range, 22-68 months). Clinical evaluations were conducted and determined by radiographs, range of motion (flexion-extension), visual analog scale, and Mayo wrist scores. Complications including nonunion and implant migration were recorded. RESULTS: Among these patients, eight developed solid radiographic union while the remaining two patients showed bone resorption and implant migration and needed revision surgeries. The visual analog scale was decreased from 5.0 to 1.1, and the flexion-extension arc was increased from 61° to 72.5°. The average Mayo Wrist Score was 70 points. The results showed outcomes similar to those of previous studies. CONCLUSION: Through our investigation and findings, we conclude that lunocapitate fusion can restore a functional and almost pain-free wrist. Moreover, these results were maintained at follow-up sessions, with complication rates being similar to those of previous studies. These results conclude a satisfactory therapeutic alternative to four-corner fusion for advanced degenerative osteoarthritis of wrists.

Mitochondrial co-chaperone protein Tid1 is required for energy homeostasis during skeletal myogenesis.

BACKGROUND: Tid1 is a mitochondrial co-chaperone protein and its transcript is abundantly expressed in skeletal muscle tissues. However, the physiological function of Tid1 during skeletal myogenesis remains unclear. METHODS: In vitro induced differentiation assay of mouse myoblast C2C12 cells was applied to examine the physiological role of Tid1 during skeletal myogenesis. In addition, transgenic mice with muscle specific (HSA-Cre) Tid1 deletion were established and examined to determine the physiological function of Tid1 during skeletal muscle development in vivo. RESULTS: Expression of Tid1 protein was upregulated in the differentiated C2C12 cells, and the HSA-Tid1f/f mice displayed muscular dystrophic phenotype. The expression of myosin heavy chain (MyHC), the protein served as the muscular development marker, was reduced in HSA-Tid1f/f mice at postnatal day (P)5 and P8. The protein levels of ATP sensor (p-AMPK) and mitochondrial biogenesis protein (PGC-1α) were also significantly reduced in HSA-Tid1f/f mice. Moreover, Tid1 deficiency induced apoptotic marker Caspase-3 in muscle tissues of HSA-Tid1f/f mice. Consistent with the in vivo finding, we observed that downregulation of Tid1 not only reduced the ATP production but also abolished the differentiation ability of C2C12 cells by impairing the mitochondrial activity. CONCLUSION: Together, our results suggest that Tid1 deficiency reduces ATP production and abolishes mitochondrial activity, resulting in energy imbalance and promoting apoptosis of muscle cells during myogenesis. It will be of importance to understand the function of Tid1 during human muscular dystrophy in the future.

Attenuation of cancer-initiating cells stemness properties by abrogating S100A4 calcium binding ability in head and neck cancers.

S100A4 is a calcium-binding protein capable of promoting epithelial-mesenchymal transition. Previously, we have demonstrated that S100A4 is required to sustain the head and neck cancer-initiating cells (HN-CICs) subpopulation. In this study, to further investigate the molecular mechanism, we established the head and neck squamous cell carcinoma (HNSCC) cell lines stably expressing mutant S100A4 proteins with defective calcium-binding sites on either N-terminal (NM) or C-terminal (CM), or a deletion of the last 15 amino-acid residues (CD). We showed that the NM, CM and CD harboring sphere cells that were enriched with HN-CICs population exhibited impaired stemness and malignant properties in vitro, as well as reduced tumor growth ability in vivo. Mechanistically, we demonstrated that mutant S100A4 proteins decreased the promoter activity of Nanog, likely through inhibition of p53. Moreover, the biophysical analyses of purified recombinant mutant S100A4 proteins suggest that both NM and CM mutant S100A4 were very similar to the WT S100A4 with subtle difference on the secondary structure, and that the CD mutant protein displayed the unexpected monomeric form in the solution phase.Taken together, our results suggest that both the calcium-binding ability and the C-terminal region of S100A4 are important for HN-CICs to sustain its stemness property and malignancy, and that the mechanism could be mediated by repressing p53 and subsequently activating the Nanog expression.

Body mass index and active range of motion exercise treatment after intra-articular injection in adhesive capsulitis.

BACKGROUND: Adhesive capsulitis is commonly associated with medical diseases such as diabetes mellitus, hyperthyroidism, and obesity. Intra-articular injection has been used to speed recovery and relieve pain associated with frozen shoulder. In this study, we evaluated and compared the effects of an intra-articular injection of corticosteroid and lidocaine in the treatment of primary adhesive capsulitis in overweight and normal-weight patients. METHODS: This is a prospective clinical study of patients with adhesive capsulitis, in which the main treatment strategy was an intra-articular injection of corticosteroid (3 mL) and lidocaine (3 mL). Active range of motion exercise was initiated immediately after the injection and performed four times daily. The evaluation included the recording of a detailed medical and orthopedic history, and the assessment of pain and function by determining the Constant score at baseline (before injection) and every 2 weeks thereafter. Patients were classified as normal weight (body mass index [BMI] < 25 kg/m(2)) or overweight (BMI ≥ 25 kg/m(2)). The Constant scores of all patients were compared at 8 weeks after injection. RESULTS: After clinical examinations and radiographic and ultrasonographic studies, 79 patients were treated for adhesive capsulitis between 2010 and 2012. In the normal-weight group, the mean Constant score increased from 35.4 to 74.6 after 8 weeks, whereas in the overweight group, the mean Constant score increased from 32.0 to 47.2. There was a significant difference in the mean Constant score between the normal-weight and overweight groups at 8 weeks. CONCLUSION: Active range of motion exercise after an intra-articular injection of corticosteroid and lidocaine improved pain and functional outcome at 8 weeks in normal-weight (BMI < 25 kg/m(2)) patients with primary adhesive capsulitis. Manipulation under anesthesia may be considered a priority in overweight patients.

Surgical treatment for septic arthritis of the knee joint in elderly patients: a 10-year retrospective clinical study.

Septic arthritis is the most rapidly destructive joint disease, but its early diagnosis remains challenging; delayed or inadequate treatment, even by expert physicians, can lead to irreversible joint destruction. Between 25% and 50% of patients develop irreversible loss of joint function, which is especially concerning in elderly patients. To understand the factors influencing the outcome of septic arthritis, the authors reviewed patients aged older than 50 years who had undergone debridement surgery for primary septic arthritis at their institution between 1998 and 2008. Ninety-two patients (92 knees) were enrolled in the study; 14 did not meet inclusion criteria and were excluded from the final analysis. Of the 78 included patients, 7 underwent arthrodesis, 22 underwent total knee arthroplasty, 19 were indicated for total knee arthroplasty for severe knee joint osteoarthritis but did not undergo surgery by the end of this study, and the remaining 30 had no or mild symptoms of osteoarthrosis and did not receive any surgical procedure. Staphylococcus aureus was the most common pathogenic agent (38%), followed by mixed bacterial infection (10%). Several factors negatively influenced the final clinical outcome, including delayed treatment, advanced macroscopic staging made during debridement surgery, performing multiple debridement surgeries, and a larger Lysholm score difference pre- and posttreatment. More antibiotics administered, longer duration of antibiotic treatment, and more pathogenic agents present were also significantly correlated with poor outcome. These findings shed new light on the management of septic arthritis. Accurate diagnoses and effective treatments are important for the clinical outcome of knee joint bacterial infection in elderly patients.

Mesenchymal stem cells from a hypoxic culture improve and engraft Achilles tendon repair.

BACKGROUND: Bone marrow-derived mesenchymal stem cells (MSCs) from humans cultured under hypoxic conditions increase bone healing capacity. HYPOTHESIS: Rat MSCs cultured under hypoxic conditions increase the tendon healing potential after transplantation into injured Achilles tendons. STUDY DESIGN: Controlled laboratory study. METHODS: Biomechanical testing, histological analysis, and bromodeoxyuridine (BrdU) labeling/collagen immunohistochemistry were performed to demonstrate that augmentation of an Achilles tendon rupture site with hypoxic MSCs increases healing capacity compared with normoxic MSCs and controls. Fifty Sprague-Dawley rats were used for the experiments, with 2 rats as the source of bone marrow MSCs. The cut Achilles tendons in the rats were equally divided into 3 groups: hypoxic MSC, normoxic MSC, and nontreated (vehicle control). The uncut tendons served as normal uncut controls. Outcome measures included mechanical testing in 24 rats, histological analysis, and BrdU labeling/collagen immunohistochemistry in another 24 rats. RESULTS: The ultimate failure load in the hypoxic MSC group was significantly greater than that in the nontreated or normoxic MSC group at 2 weeks after incision (2.1 N/mm(2) vs 1.1 N/mm(2) or 1.9 N/mm(2), respectively) and at 4 weeks after incision (5.5 N/mm(2) vs 1.7 N/mm(2) or 2.7 N/mm(2), respectively). The ultimate failure load in the hypoxic MSC group at 4 weeks after incision (5.5 N/mm(2)) was close to but still significantly less than that of the uncut tendon (7.2 N/mm(2)). Histological analysis as determined by the semiquantitative Bonar histopathological grading scale revealed that the hypoxic MSC group underwent a significant improvement in Achilles tendon healing both at 2 and 4 weeks when compared with the nontreated or normoxic MSC group via statistical analysis. Immunohistochemistry further demonstrated that the hypoxic and normoxic MSC groups had stronger immunostaining for type I and type III collagen than did the nontreated group both at 2 and 4 weeks after incision. Moreover, BrdU labeling of MSCs before injection further determined the incorporation and retention of transplanted cells at the rupture site. CONCLUSION: Transplantation of hypoxic MSCs may be a better and more readily available treatment than normoxic MSCs for Achilles tendon ruptures. CLINICAL RELEVANCE: The present study provides evidence that transplantation of hypoxic MSCs may be a promising therapy for the treatment of Achilles tendon ruptures.

Isolation of mesenchymal stem cells from shoulder rotator cuff: a potential source for muscle and tendon repair.

The self-healing potential of each tissue belongs to endogenous stem cells residing in the tissue; however, there are currently no reports mentioned for the isolation of human rotator cuff-derived mesenchymal stem cells (RC-MSCs) since. To isolate RC-MSCs, minced rotator cuff samples were first digested with enzymes and the single cell suspensions were seeded in plastic culture dishes. Twenty-four hours later, nonadherent cells were removed and the adherent cells were further cultured. The RC-MSCs had fibroblast-like morphology and were positive for the putative surface markers of MSCs, such as CD44, CD73, CD90, CD105, and CD166, and negative for the putative markers of hematopoietic cells, such as CD34, CD45, and CD133. Similar to BM-MSCs, RC-MSCs were demonstrated to have the potential to undergo osteogenic, adipogenic, and chondrogenic differentiation. Upon induction in the defined media, RC-MSCs also expressed lineage-specific genes, such as Runx 2 and osteocalcin in osteogenic induction, PPAR-γ and LPL in adipogenic differentiation, and aggrecan and Col2a1 in chondrogenic differentiation. The multipotent feature of RC-MSCs in the myogenic injury model was further strengthened by the increase in myogenic potential both in vitro and in vivo when compared with BM-MSCs. These results demonstrate the successful isolation of MSCs from human rotator cuffs and encourage the application of RC-MSCs in myogenic regeneration.

Rotator cuff tears in patients younger than 50 years of age.

The purpose of this study was to investigate the characteristics of rotator cuff tears and the clinical outcome of rotator cuff repair in patients under 50 years of age. Sixty-eight patients (72 shoulders) aged < 50 years, who underwent repair of rotator cuff tears were evaluated. We analyzed the cause of injury, tear size, time from symptom onset to surgery, and rate that patients returned to previous jobs and sports. Postoperative results were assessed by pain, strength, range of motion, and UCLA scoring system. Most of the injuries were caused by an unambiguous traumatic event. The tear size generally was medium or large, while the time from symptom onset to surgery was shorter than that seen in a mixed population. The postoperative outcomes generally were good to excellent, and the rate that patients returned to previous jobs and sports was high. The findings suggest that a good outcome after early repair in younger patients with traumatic rotator cuff tears can be expected.

Bilateral stress fractures of the ulna in a young adolescent.

We present a case of bilateral ulnar stress fractures in a young male adolescent (15 years old) due to honour guard training and discuss the possible mechanism of this injury. In addition to acquisition of medical history, physical examination and plain radiography, we performed MRI to exclude pathological causes and confirm the plain radiographic findings, indicating stress reactions. Ulnar stress fractures are bone injuries caused by repetitive muscle pull and the reaction of supporting tissues. In honour guard training, the acceleration due to gravity and chronic torsional stress may also contribute to overloading. Thus, such fractures are best managed by avoiding overloading. In addition, we review the literature on stress fractures of the ulnar shaft to map this special kind of fracture.