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-β 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.

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.

Hoffa fracture: fixation using headless compression screws

INTRODUCTION

Hoffa fractures are uni- or bicondylar fractures of the distal femur in a coronal tangential plane.

CASE PRESENTATION

We report the case of an isolated, low energy, closed, displaced, lateral femoral condyle Hoffa fracture in a 54 year old Caucasian man. This was treated by open reduction and internal fixation using two headless compression screws. At 1 year review the patient was pain free, the fracture had radiographically united and there was a range of movement to his knee of 0°-100°.

DISCUSSION

Traditional methods of fixation for Hoffa fractures have led either to the application of complicated constructs attempting to achieve stability, or to large articular surface defects created whilst countersinking headed lag screws. Both have negative implications for the patient. We describe a novel method, not previously described in the literature, using screws in a posterior to anterior direction. This provides compression perpendicular to the fracture site whilst protecting against shear and torsional forces, thereby providing more stable fixation. Furthermore, our method allows for a minimally invasive approach and uses headless compression screws, which reduces the chance of damage to the articular surface and is, therefore, less physiologically invasive.