Normal human enthesis harbours conventional CD4+ and CD8+ T cells with regulatory features and inducible IL-17A and TNF expression.

BACKGROUND: The human enthesis conventional T cells are poorly characterised. OBJECTIVES: To study the biology of the conventional T cells in human enthesis. METHODS: CD4+ and CD8+ T cells were investigated in 25 enthesis samples using immunofluorescence, cytometrically, bulk RNAseq and quantitative real-time PCR following anti-CD3/CD28 bead stimulation to determine interleukin (IL)-17A and tumour necrosis factor (TNF) levels. T-cell receptor (TCR) repertoires were characterised and a search for putative T-cell reactivity was carried out using TCR3 database. The impact of pharmacological antagonism with retinoic acid receptor-related orphan nuclear receptor gamma t inhibitor (RORγti), methotrexate and phosphodiesterase type 4 inhibitor (PDE4i) was investigated. RESULTS: Immunofluorescence and cytometry suggested entheseal resident CD4+ and CD8+ T cells with a resident memory phenotype (CD69+/CD45RA-) and tissue residency gene transcripts (higher NR4A1/AhR and lower KLF2/T-bet transcripts). Both CD4+ and CD8+ T cells showed increased expression of immunomodulatory genes including IL-10 and TGF-ß compared with peripheral blood T cells with entheseal CD8+ T cells having higher CD103, CD49a and lower SIPR1 transcript that matched CD4+ T cells. Following stimulation, CD4+ T cells produced more TNF than CD8+ T cells and IL-17A was produced exclusively by CD4+ T cells. RNAseq suggested both Cytomegalovirus and influenza A virus entheseal resident T-cell clonotype reactivity. TNF and IL-17A production from CD4+ T cells was effectively inhibited by PDE4i, while RORγti only reduced IL-17A secretion. CONCLUSIONS: Healthy human entheseal CD4+ and CD8+ T cells exhibit regulatory characteristics and are predicted to exhibit antiviral reactivity with CD8+ T cells expressing higher levels of transcripts suggestive of tissue residency. Inducible IL-17A and TNF production can be robustly inhibited in vitro.

Postoperative Rigid Cervical Collar Leads to Less Axial Neck Pain in the Early Stage After Open-Door Laminoplasty-A Single-Blinded Randomized Controlled Trial.

BACKGROUND: Cervical collars are used after laminoplasty to protect the hinge opening, reduce risks of hinge fractures, and avoid spring-back phenomena. However, their use may lead to reduced range of motion and worse neck pain. OBJECTIVE: To investigate the clinical, radiological, and functional outcomes of patients undergoing single-door laminoplasty with or without collar immobilization. METHODS: This was a prospective, parallel, single-blinded randomized controlled trial. Patients underwent standardized single-door laminoplasty with mini-plates for cervical myelopathy and were randomly allocated into 2 groups based on the use of collar postoperatively. Clinical assessments included cervical range of motion, axial neck pain (VAS [visual analogue scale]), and objective scores (short-form 36-item, neck disability index, and modified Japanese Orthopaedic Association). All assessments were performed preoperatively and at postoperative 1, 2, 3, and 6 wk, and 3, 6, and 12 mo. Comparative analysis was performed via analysis of variance adjusted by baseline scores, sex, and age as covariates. RESULTS: A total of 35 patients were recruited and randomized to collar use (n = 16) and without (n = 19). There were no dropouts or complications. There were no differences between groups at baseline. Subjects had comparable objective scores and range of motion at postoperative time-points. Patients without collar use had higher VAS at postoperative 1 wk (5.4 vs 3.5; P = .038) and 2 wk (3.5 vs 1.5; P = .028) but subsequently follow-up revealed no differences between the 2 groups. CONCLUSION: The use of a rigid collar after laminoplasty leads to less axial neck pain in the first 2 wk after surgery. However, there is no additional benefit with regards to range of motion, quality of life, and complication risk.

The use of the 4.5 mm 90° titanium cannulated LC-angled blade plate in tibiotalocalcaneal and complex ankle arthrodesis.

BACKGROUND: Tibiotalocalcaneal arthrodesis is used to manage end stage arthritis, often associated with severe bone loss. The goal is to relieve pain through a stable, well-aligned hindfoot and ankle. We describe our initial results and outcome of ankle and tibiotalocalcaneal arthrodesis using a 90° blade plate. METHODS: We retrospectively reviewed the records of patients managed at our institution between 2010 and 2014. Twenty cases were identified who had either talocrural (n = 9) or TTC fusion (n = 11) with 1 patient having both ankle and then TTC fusion in separate sittings. RESULTS: Fusion occurred in 18 of the 20 cases (90%) with correction of angular deformity and restoration of hindfoot alignment. None of the 18 patients developed complications and all discharged to follow-up when independently mobile and satisfied with the outcome. CONCLUSIONS: This study demonstrated that using a 90° blade plate for ankle or TTC arthrodesis in a diverse group of complex primary and revision indications associated with severe deformity and bone loss resulted in a high rate of bony union and stable deformity correction.

Biomechanics of low-modulus and standard acrylic bone cements in simulated vertebroplasty: A human ex vivo study.

The high stiffness of bone cements used in vertebroplasty has been hypothesised to contribute to the propensity of adjacent vertebral fractures after treatment. Therefore, new low-modulus cements have been developed; however, there are currently no studies assessing the biomechanical aspects of vertebroplasty with these cements in an ex vivo non-prophylactic model. In this study, we induced wedge fractures through eccentric uniaxial compression to single whole-vertebrae, before and after augmentation with either standard or low-modulus cement. Compressive strength and stiffness of individual vertebrae were measured, on 19 samples from metastatic spines and 20 samples from elderly, osteopenic spines. While both cement types increased the strength of both the metastatic (+34% and +63% for standard and low-modulus cement, respectively) and the elderly vertebrae (+303% and +113%, respectively), none of them restored the initial stiffness of metastatic specimens (-51% and -46%, respectively). Furthermore, low-modulus cement gave a lower total stiffness (-13%) of elderly specimens whereas standard cement increased it above initial levels (+17%). Results show that vertebroplasty with low-modulus cement could provide restoration of the initial stiffness while increasing the strength of fractured elderly vertebrae and hence represent a treatment modality which is closer to pre-augmented behaviour. Also, this study indicates that stiffness-modified cement needs to be optimised for patient/pathology specific treatment.

Medial displacement calcaneal osteotomy using minimally invasive technique.

BACKGROUND: Medial displacement calcaneal osteotomy is a common procedure often used as part of pes planovalgus deformity correction. Traditionally the osteotomy is performed using a direct lateral or extended lateral approach, which may carry the risk of wound problems, infection and neurovascular injury. The authors describe a minimally invasive technique to perform the osteotomy and achieve the desired correction. The article illustrates our experience and learning curve with the use of this technique as an option for calcaneal osteotomy. METHODS: We retrospectively reviewed the records of a sequential series of patients since 2011 whose calcaneal osteotomies were performed by 2 surgeons, after cadaveric training using a minimally invasive operative approach. Prior to 2011, similar surgeries, performed by the senior authors, were undertaken using a direct lateral approach. Thirty cases were identified; 29 had tibialis posterior reconstruction coupled with calcaneal osteotomy for acquired flexible planovalgus deformity and 1 patient had surgery for a malunited calcaneal fracture. RESULTS: Radiological and clinical union occurred in all 30 cases (100%). The radiographs of all cases were reviewed by a specialist musculoskeletal radiologist. There were no neurovascular or wound complications. All patients had restoration of neutral hindfoot alignment. One patient required screw removal after union, resolving all symptoms. CONCLUSION: This series suggests that minimally invasive calcaneal osteotomy surgery can achieve excellent union rates aiding correction of deformity with no observed neurovascular or soft tissue complications. For surgeons experienced in open surgery, there is a short learning curve after appropriate training.

Lessons to be learned from a missed case of Hamate fracture: a case report.

INTRODUCTION: We report the case of a missed fracture through the body of the hamate bone, only detected on a later, mistakenly taken 30° oblique x-ray view. This case highlights some of the problems encountered with traditional x-ray views, and the need to consider oblique views as either standard procedure or as an adjunct where clinical suspicion remains high even in the presence of normal x-rays. CASE PRESENTATION: A healthy 26-year-old Caucasian male fell whilst jogging, suffering a low velocity injury to his right hand. Initial accident and emergency examination and x-rays failed to demonstrate a fracture. At clinic, anteroposterior and carpal tunnel radiographs showed no fracture, however a mistakenly taken oblique x-ray revealed a displaced hamate body fracture. CONCLUSION: The authors believe that where a hamate fracture is suspected, an oblique x-ray view should be considered as part of the initial diagnostic investigations. Furthermore an oblique x-ray view is of particular use when clinical suspicion for hamate fracture remains high in the light of otherwise normal x-rays.