The effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament reconstruction: An animal study

Objectives

To compare the effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament (ACL) reconstruction animal model.

Methods

Anterior cruciate ligament reconstruction using the plantaris tendon as graft material was performed on both knees of 24 rabbits (48 knees) to mimic ACL reconstruction by two different suspensory fixation devices for graft fixation. For the adjustable fixation device model (Socket group; group S), a 5 mm deep socket was created in the lateral femoral condyle (LFC) of the right knee. For the fixed-loop model (Tunnel group; group T), a femoral tunnel penetrating the LFC was created in the left knee. Animals were sacrificed at four and eight weeks after surgery for histological evaluation and biomechanical testing.

Results

Histologically, both groups showed a mixture of direct and indirect healing patterns at four weeks, whereas only indirect healing patterns were observed in both groups at eight weeks. No significant histological differences were seen between the two groups at four and eight weeks in the roof zone (four weeks, S: mean 4.8 sd 1.7, T: mean 4.5 sd 0.5, p = 0.14; eight weeks, S: mean 5.8 sd 0.8, T: mean 4.8 sd 1.8, p = 0.88, Mann-Whitney U test) or side zone (four weeks, S: mean 5.0 sd 1.2, T: mean 4.8 sd 0.4, p = 0.43; eight weeks, S: mean 5.3 sd 0.8,T: mean 5.5 sd 0.8, p = 0.61, Mann-Whitney U test) . Similarly, no significant difference was seen in the maximum failure load between group S and group T at four (15.6 sd 9.0N and 13.1 sd 5.6N) or eight weeks (12.6 sd 3.6N and 17.1 sd 6.4N, respectively).

Conclusion

Regardless of bone tunnel configuration, tendon-bone healing after ACL reconstruction primarily occurred through indirect healing. No significant histological or mechanical differences were observed between adjustable and fixed-loop femoral cortical suspension methods.

Cite this article: Y. Sato, R. Akagi, Y. Akatsu, Y. Matsuura, S. Takahashi, S. Yamaguchi, T. Enomoto, R. Nakagawa, H. Hoshi, T. Sasaki, S. Kimura, Y. Ogawa, A. Sadamasu, S. Ohtori, T. Sasho. The effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament reconstruction: An animal study. Bone Joint Res 2018;7:327–335. DOI: 10.1302/2046-3758.75.BJR-2017-0238.R2.

Analysis of masticatory muscle coordination during unilateral single-tooth clenching using muscle functional magnetic resonance imaging

In a previous study, we used muscle functional magnetic resonance imaging to show that the anterior movement of the occlusal point increased the activity of the superior head of the ipsilateral lateral pterygoid muscle (ipsilateral SHLP) during unilateral single-tooth clenching. The purpose of this study was to verify the hypothesis that the increased activity of the ipsilateral SHLP described above serves to antagonise the occlusal force acting on the condyle. In total, 9 healthy volunteers were requested to perform left unilateral clenching at the first molar or first premolar region for 1 minute at 20% or 40% maximum voluntary clenching force. Changes in the mean proton transverse relaxation time (∆T2) were examined from the magnetic resonance images obtained before and after each clenching act as an index of the activity in all masticatory muscles. Correlation analyses of the mean ΔT2 for each volume of interest were performed with the first molar or premolar clenches to analyse the correlation between the activities in each muscle. A statistically significant correlation was exhibited between the ipsilateral temporal and ipsilateral SHLP (r = .651, P = .003) during first premolar clenching. However, no significant correlations were observed in the ipsilateral SHLP during first molar clenching. The results of this study suggest that the ipsilateral SHLP may contribute to the pulling of the mandibular condyle forward against the occlusal force generated by the ipsilateral temporal muscle.

A randomized controlled phase II clinical trial comparing ONO-4053, a novel DP1 antagonist, with a leukotriene receptor antagonist pranlukast in patients with seasonal allergic rhinitis

BACKGROUND

Prostaglandin D2 (PGD2 ) is primarily produced by mast cells and is contributing to the nasal symptoms including nasal obstruction and rhinorrhea.

OBJECTIVE

This study aimed to evaluate the efficacy and safety of a novel PGD2 receptor 1 (DP1) antagonist, ONO-4053, in patients with seasonal allergic rhinitis (SAR).

METHODS

This study was a multicenter, randomized, double-blind, parallel-group study of patients with SAR. Following a one-week period of placebo run-in, patients who met the study criteria were randomized to either the ONO-4053, leukotriene receptor antagonist pranlukast, or placebo group for a two-week treatment period. A total of 200 patients were planned to be randomly assigned to receive ONO-4053, pranlukast, or placebo in a 2:2:1 ratio. Nasal and eye symptoms were evaluated.

RESULTS

Both ONO-4053 and pranlukast had higher efficacy than placebo on all nasal and eye symptoms. ONO-4053 outperformed pranlukast in a total of three nasal symptom scores (T3NSS) as well as in individual scores for sneezing, rhinorrhea, and nasal itching. For T3NSS, the Bayesian posterior probabilities that pranlukast was better than placebo and ONO-4053 was better than pranlukast were 70.0% and 81.6%, respectively, suggesting that ONO-4053 has a higher efficacy compared with pranlukast. There was no safety-related issue in this study.

CONCLUSIONS

We demonstrated that the efficacy of ONO-4053 was greater than that of pranlukast with a similar safety profile. This study indicates the potential of ONO-4053 for use as a treatment for SAR (JapicCTI-142706).

Physiological exercise loading suppresses post-traumatic osteoarthritis progression via an increase in bone morphogenetic proteins expression in an experimental rat knee model

OBJECTIVE

To evaluate the dose-response relationship of exercise loading in the cartilage-subchondral bone (SB) unit in surgically-induced post-traumatic osteoarthritis (PTOA) of the knee.

DESIGN

Destabilized medial meniscus (DMM) surgery was performed on the right knee of 12-week-old male Wistar rats, and sham surgery was performed on the contralateral knee. Four weeks after the surgery, the animals were subjected to moderate (12 m/min) or intense (21 m/min) treadmill exercises for 30 min/day, 5 days/week for 4 weeks. PTOA development in articular cartilage and SB was examined using histological and immunohistochemical analyses, micro-computed tomography (micro-CT) analysis, and biomechanical testing at 8 weeks after surgery. Gremlin-1 was injected to determine the role of bone morphogenetic protein (BMP) signaling on PTOA development following moderate exercise.

RESULTS

Moderate exercise increased BMP-2, BMP-4, BMP-6, BMP receptor 2, pSmad-5, and inhibitor of DNA binding protein-1 expression in the superficial zone chondrocytes and suppressed cartilage degeneration, osteophyte growth, SB damage, and osteoclast-mediated SB resorption. However, intense exercise had little effect on BMP expression and even caused progression of these osteoarthritis (OA) changes. Gremlin-1 injection following moderate exercise caused progression of the PTOA development down to the level of the non-exercise DMM-operated knee.

CONCLUSIONS

Exercise regulated cartilage-SB PTOA development in DMM-operated knees in a dose-dependent manner. Our findings shed light on the important role of BMP expression in superficial zone chondrocytes in attenuation of PTOA development following physiological exercise loading. Further studies to support a mechanism by which BMPs would be beneficial in preventing PTOA progression are warranted.

Detection of high serum levels of β-D-Glucan in disseminated nocardial infection: a case report

Background

β-D-glucan (BDG) is a helpful diagnostic marker for many invasive fungal infections, but not for nocardiosis. Here, we reported the first case of nocardial infection with high serum level of BDG.

Case presentation

A 73-year-old man was hospitalized because of fever, headache, and appetite loss after 10 months of steroid and immunosuppressive therapy for cryptogenic organizing pneumonia. With a diagnosis of bacterial pneumonia, treatment with ampicillin/sulbactam was initiated. There was improvement on chest radiograph, but fever persisted. Further work-up revealed multiple brain abscesses on cranial magnetic resonance imaging (MRI). Serum galactomannan and BDG were elevated at 0.6 index and 94.7 pg/ml, respectively. Voriconazole was initiated for presumed aspergillus brain abscess. However, fever persisted and consciousness level deteriorated. Drainage of brain abscess was performed; based on the Gram stain and Kinyoun acid-fast stain, disseminated nocardiosis was diagnosed. Voriconazole was then shifter to trimethoprim/sulfamethoxazole. The presence of Nocardia farcinica was confirmed by the 16S rRNA gene sequence. Treatment course was continued; BDG level normalized after 1 month and cranial MRI showed almost complete improvement after 2 months.

Conclusion

BDG assay is widely used to diagnose invasive fungal infection; therefore, clinicians should be aware that Nocardia species may show cross-reactivity with BDG assay on serum.

The recognition and incidence of peroneal tendon dislocation associated with a fracture of the talus

AIMS

The purposes of this study were to clarify first, the incidence of peroneal tendon dislocation in patients with a fracture of the talus and second the factors associated with peroneal tendon dislocation.

PATIENTS AND METHODS

We retrospectively examined 30 patients (30 ankles) with a mean age of 37.5 years, who had undergone internal fixation for a fracture of the talus. Independent examiners assessed for peroneal tendon dislocation using the pre-operative CT images. The medical records were also reviewed for the presence of peroneal tendon dislocation. The associations between the presence of dislocation with the patient characteristics or radiological findings, including age, mechanism of injury, severity of fracture, and fleck sign, were assessed using Fisher's exact tests.

RESULTS

The pre-operative CT images showed peroneal tendon dislocation in eight out of 30 patients. Dislocation was found later in one patient whose pre-operative CT image had not shown dislocation. The overall incidence of peroneal tendon dislocation was 30% (9/30). The presence of dislocation was associated with the presence of a fleck sign (p = 0.03).

CONCLUSIONS

Surprisingly, approximately one-third of the patients who underwent internal fixation for a fracture of the talus had peroneal tendon dislocation. This was associated with a fleck sign. Cite this article: Bone Joint J 2017;99-B:489-93.

Development of 2-D horn-antenna millimeter-wave imaging device (HMID) for the plasma diagnostics

The two-dimensional (2-D) Horn-antenna Millimeter-wave Imaging Device (HMID) has been developed for the O-mode Microwave Imaging Reflectometry (O-MIR) in the Large Helical Device (LHD). The detectable frequency range of the HMID is 23-33 GHz, which corresponds to the cutoff electron density of 0.8-1.5 × 10¹⁹ m^-3 in the O-MIR. The HMID is a 2-D imaging device that improves on the horn-antenna mixer array, which had been developed for the X-mode MIR in the LHD. In the HMID, the signal (RF) wave from the horn antenna is transmitted to the microstrip line by the finline transmitter, and this is mixed by the double-balanced-mixer with the local oscillation wave that is fed by a coaxial cable. By using the HMID, the MIR optical system can be significantly simplified.

Selective intracellular vaporisation of antibody-conjugated phase-change nano-droplets in vitro

While chemotherapy is a major mode of cancer therapeutics, its efficacy is limited by systemic toxicities and drug resistance. Recent advances in nanomedicine provide the opportunity to reduce systemic toxicities. However, drug resistance remains a major challenge in cancer treatment research. Here we developed a nanomedicine composed of a phase-change nano-droplet (PCND) and an anti-cancer antibody (9E5), proposing the concept of ultrasound cancer therapy with intracellular vaporisation. PCND is a liquid perfluorocarbon nanoparticle with a liquid–gas phase that is transformable upon exposure to ultrasound. 9E5 is a monoclonal antibody targeting epiregulin (EREG). We found that 9E5-conjugated PCNDs are selectively internalised into targeted cancer cells and kill the cells dynamically by ultrasound-induced intracellular vaporisation. In vitro experiments show that 9E5-conjugated PCND targets 97.8% of high-EREG-expressing cancer cells and kills 57% of those targeted upon exposure to ultrasound. Furthermore, direct observation of the intracellular vaporisation process revealed the significant morphological alterations of cells and the release of intracellular contents.