16S rRNA sequencing reveals microbiota differences in orthopedic implants between aseptic loosening and prosthetic joint infection cases

Prosthetic joint infection (PJI) and aseptic loosening (AL) are common complications of total joint arthroplasty. An accumulation of evidence indicates the presence of microbial communities on prosthetic implants, but the overall microbial profile is unclear. In this study, we aimed to investigate the differences in the microbial composition of prosthetic implants obtained from PJI and AL patients using the 16S rRNA sequencing method. Patients who underwent revision hip, knee, or shoulder arthroplasty caused by PJI (n = 20) or AL (n = 10) were enrolled in the study. 16S rRNA sequencing targeting the V3-V4 region was performed on the microbial specimens collected from synovial fluid, periprosthetic deep-tissue, and biofilm during the revision surgery. The sequenced raw data were analysed for microbial composition and ecological and differential abundance analyses using bioinformatics tools. The AL group had relatively balanced and higher diversity, with Staphylococcus, Streptococcus, and Veillonella being prominent. In the PJI group, Staphylococcus and Pseudomonas were predominant, especially in deep-tissue samples and biofilm samples, respectively. The differential abundance analysis identified 15 and 2 distinctive taxa in the AL and PJI groups, respectively. Our findings provided preliminary insights supporting the existence of periprosthetic microbiota in orthopedic implants and explaining the differences in microbial composition between the AL and PJI groups.

Clinical and radiological results of surgically treated patients with adolescent idiopathic scoliosis and the effects of pulmonary rehabilitation on respiration functions

BACKGROUND

In the present study, we aimed to evaluate the effects of pulmonary rehabilitation on respiratory functions after the surgery on the basis of early radiological findings, pain degree, function, and satisfaction scores in operated patients with adolescent idiopathic scoliosis (AIS).

METHODS

Thirty patients with AIS were included in the present study, who were divided into 2 groups. Scoliosis surgery and diaphragmatic breathing and pursed lip exercises were applied in Group 1 (n = 15), whereas merely scoliosis surgery was applied in Group 2 (n = 15). Pulmonary functions, arterial blood gas analysis, Cobb and kyphosis angles, apical vertebral rotation, and apical vertebral translation were measured before and 1st and 6th months after the surgery. Using the SRS-30 test, the psychosocial statuses of the patients and their satisfaction degrees with surgery applied were measured before and after the surgery.

RESULTS

Six months after the surgery, the values of Cobb and kyphosis angles and apical vertebral rotations, and apical vertebral translation of the patients were determined to be significantly ameliorated, which is consistent with the literature. Forced vital capacity (l) and forced expiratory volume in the first second (l/s) were observed to be significantly improved in both groups after the surgery (respectively, P = .001, P = .014, P = .001, P = .005). In addition, the partial pressure of oxygen (pO2) value was found to be significantly increased 6 months after the surgery compared with that before the surgery in Group 2 (P = .022). SRS-30 showed that most of the scores in Group 1 were dramatically increased; a significant difference between the groups was not recorded.

CONCLUSION

Patients with AIS have been found to be satisfied with the surgery. Conversely, pulmonary rehabilitation has been shown to slightly improve the respiratory functions in the patients with AIS, 1 and 6 months after the surgery.

Diffusion tensor imaging of the median nerve healing. Preliminary results

AIMS

This study aimed to examine the correlation between DTI, clinical assessment, and electromyography results in patients who underwent primary median nerve repair.

METHODS

Ten patients who underwent primary repair of the complete median nerve transection were included. Study assessments were performed on both the traumatized and non-traumatized extremities and patients were followed up for a minimum duration of 11 months. Clinical assessments, (Tinnel test, static 2-point discrimination test, motor and quality of life assessments), electromyography and DTI were performed.

RESULTS

None of the clinical or electromyographic parameters correlated significantly with any of the diffusion tensor imaging parameters, i.e. fractional anisotropy (FA) or apparent diffusion coefficient (ADC) (p>0.05 for all). In addition, The Disabilities of the Arm, Shoulder and Hand (DASH) scores did not correlate with either FA (r=0.55, p=0.098) or ADC (r=0.40, p=0.260) values. However, Tinnel positive cases (n=3) had lower relative FA when compared to Tinnel negative cases (n=7) (-0.11±0.19 vs. 0.05±0.04, p=0.033).

CONCLUSION

Our findings do not support the presence of relations between DTI parameters and electromyographic or most of the clinical parameters. Further MRI studies with larger numbers of patients with complete transection of the median nerve using the novel imaging parameters are warranted.

KEY WORDS

Diffusion Tensor Imaging (DTI), Electromyography (EMG), Median nerve, Nerve injury, Nerve repair.

Comparison of Intra-articular Injection of Hyaluronic Acid and N-Acetyl Cysteine in the Treatment of Knee Osteoarthritis: A Pilot Study

Objective To compare the relative effectiveness of intra-articular N-acetyl cysteine (NAC) and hyaluronic acid (HA) on pain, function and cartilage degradation markers in patients with mild to moderate knee osteoarthritis (OA). Design We prospectively conducted a clinical trial with 20 patients having a diagnosis of Kellgren-Lawrence grade 2-3 knee OA, and randomly allocated to the HA or NAC groups. Groups were matched on age, sex, and body mass index. Injections of 3-mL HA (Hylan G-F 20) or 3-mL NAC (Asist ampoule) were administered as a single shot. Functional status and pain were evaluated before and after injection, using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and the visual analogue scale (VAS) scores. Pre- and posttreatment concentrations of serum C-reactive protein (CRP), synovial fluid chondroitin-6-sulfate (C-6S), matrix metalloproteinase-3 (MMP-3), cross-linked C-terminal telopeptide of type 2 collagen (CTX-II), total oxidant status (TOS), and total antioxidant concentration (TAC) were obtained. Results WOMAC, VAS scores, and CRP levels were comparable between groups prior to treatment. Both HA and NAC produced comparable reductions in TOS and MMP-3. NAC was more effective in reducing C-6S and CTX-II ( P < 0.05). No effects on TAC were noted. Conclusions NAC is effective in lowering some cartilage degradation markers, with comparable outcomes to HA for pain and function. NAC could provide a cheaper alternative to HA for intra-articular injection treatment of mild to moderate knee OA. Future placebo controlled trials are warranted to evaluate effectiveness in a larger patient population with a wider range of age and OA severity.

The effect of erythropoietin on biomechanical properties of the Achilles tendon during the healing process: an experimental study

Background

The aim of this study was to examine the potential biomechanical and histological benefits of systemic erythropoietin administration during the healing of Achilles tendon injury in a rat experimental model.

Methods

Eighty Sprague-Dawley female rats were included in this study. Animals were randomly assigned into two groups with 40 animals in each: erythropoietin group and control group. Then each group was further divided into four subgroups corresponding to four time points with 10 animals in each. A full-thickness cut was made on the Achilles tendon of each animal and then the tendon was sutured with modified Kessler method. Erythropoietin groups received intraperitoneal erythropoietin (500 IU/kg/day) every day at same time throughout the study period, and the control groups received saline in a similar manner. Animals were sacrificed at four time points, and tensile test was performed on each tendon sample to assess maximum load for each sample. In addition, histopathological examination and scoring was done.

Results

Both groups had improvement on tensile test (maximum load) over time. However, groups did not differ with regard to maximum load in any of the time points. Similarly, groups did not differ with regard to any of the histopathological scores over time.

Conclusions

The findings of this study do not support the benefit of systemic erythropoietin administration in Achilles tendon healing process. Further evidence from larger experimental studies is required to justify any such potential benefit.

Electronic supplementary material

The online version of this article (doi:10.1186/s13018-016-0390-1) contains supplementary material, which is available to authorized users.

Biomechanical properties of Achilles tendon in diabetic vs. non-diabetic patients

BACKGROUND/OBJECTIVES

Structural and functional impairments of the Achilles tendon in diabetic patients has the potential to contribute to ulcer formation through altered foot mechanics. This study aimed to examine the biomechanical and histopathological alterations in Achilles tendon specimens from diabetic vs. non-diabetic individuals.

MATERIALS AND METHODS

42 Achilles tendon samples obtained from patients treated with below-knee or above-knee amputation for chronic diabetic foot ulcers (n=21) or for non-diabetic conditions (n=21) were included. A tensile test was performed for each tendon and a stress vs. strain graft was obtained to calculate following biomechanical parameters: elasticity (Young modulus), load, stiffness, toughness, energy, strain, elongation and tenacity. Groups were also compared with regard to histopathological findings (inflammatory cell infiltration, collagen organization, and degeneration).

RESULTS

Non-diabetic tendons exhibited a superior biomechanical profile over diabetic tendons with regard to the following biochemical parameters: elasticity, maximum load, stiffness, toughness, load, energy, strain and elongation at break point, tenacity, and strain at automatic load drop (p<0.05 for all comparisons). Diabetic tendons had mild impairment of collagen organization and focal collagen degeneration, whereas neither diabetic nor non-diabetic tendons had inflammatory cell infiltration.

CONCLUSION

The structural and functional alterations associated with diabetes adversely affect the biomechanical properties of the Achilles tendon, potentially acting together with neuropathy and ischemia in the development of diabetic foot ulcers.

Comparison of arthroscopic, radioactive and combined synovectomy in the treatment of chronic non-specific knee synovitis

OBJECTIVE

To compare the outcomes of arthroscopic, radioactive and combined synovectomies in patients with chronic non-specific recurrent synovitis who did not respond to conservative therapy.

SUBJECTS AND METHODS

Twenty-nine patients enrolled between 2007 and 2011 were divided into 3 groups: group 1 was treated with arthroscopy, group 2 received a radioactive drug and group 3 received a combined (radioactive and arthroscopic) synovectomy. Treatment efficacy was evaluated by comparing pre- and post-operative Lysholm knee scores (LKS), night pain, resting pain, activity pain and effusions using visual analogue scales (VAS). Patient satisfaction was assessed using the visual analogue patient satisfaction scale (VAPSS).

RESULTS

The mean age of the study participants was 41.5 ± 5.2 years (range 14-76), and the mean follow-up period was 33.6 ± 3.2 months (range 17-78). Before treatment, the mean LKS was 41.4 ± 3.4 in group 1, 39.6 ± 3.3 in group 2 and 37.1 ± 4.6 in group 3. After treatment, the corresponding mean LKS were 77.7 ± 2.1, 81.6 ± 2.8 and 91.3 ± 2.7 in groups 1, 2 and 3, respectively; the increase was statistically significant (p < 0.05). The VAS scores before and after treatment decreased significantly (p < 0.05). The mean VAPSS score, a measure of patient satisfaction, was 5.1 ± 1.7, 5.8 ± 1.5 and 7.4 ± 1.8 in groups 1, 2 and 3, respectively, and the difference between groups 1 and 2 was not statistically significant, while that between group 3 and the other two groups was significant (p < 0.05).

CONCLUSION

This study showed that the three methods used in individuals with chronic non-specific recurrent synovitis were effective; however, arthroscopic synovectomy in combination with radioactive synovectomy was more effective than the other methods and superior in terms of patient satisfaction.

Royal jelly and bee pollen decrease bone loss due to osteoporosis in an oophorectomized rat model

OBJECTIVES

In this study, we aimed to investigate whether royal jelly and bee pollen reduce the bone loss due to osteoporosis in oophorectomized rat model.

MATERIALS AND METHODS

Thirty-two female Sprague-Dawley mature rats at six-month-old, weighing 180-260 g were used in the study. The rats were divided into four groups: Sham-operation group, only oophorectomy group, oophorectomy in combination with royal jelly group, and oophorectomy and bee pollen group. The rats were sacrified within 12 weeks following surgery. Bone mineral density (BMD) was measured and blood samples were collected for biochemical analysis before sacrification. Following sacrification, uterine weights were measured and tissue samples were taken to determine bone calcium and phosphate level with imaging through scanning electron microscope.

RESULTS

The uterine weights of the rats were found higher in Sham-operation group than the other groups. The difference among the groups was statistically significant (p=0.001). Total body BMD results were similar in all groups and there was not statistically significant difference (p=0.19). The lumbar spine and proximal femur BMD results were statistically significantly higher in the royal jelly and bee pollen groups, compared to only oophorectomy group (p=0.001). Bone tissue calcium and phosphate levels were higher in royal jelly and bee pollen groups.

CONCLUSION

Royal jelly and bee pollen decrease the bone loss due to osteoporosis in oophorectomized rat model. These results may contribute to the clinical practice.