Qualitative and quantitative assessment of cartilage degeneration using full-field optical coherence tomography ex vivo.

OBJECTIVE: The purpose of this study was to investigate the ability of full-field optical coherence tomography (FFOCT) to qualitatively and quantitatively evaluate cartilage degeneration using the qualitative evaluation of histology sections as the reference. DESIGN: Thirty-three human knee cartilage samples of variable degeneration were included in the study. A closely matching histology and FFOCT image was acquired for each sample. The cartilage degeneration was qualitatively evaluated by assigning a grade to each histology and FFOCT image. The relevance of the performed grading was assessed by calculating the intra- and inter-observer reproducibility and calculating the concordance between the histology and FFOCT grades. A near-automatic algorithm was developed to quantitatively characterize the cartilage surface in each image. The correlation between the quantitative results and the reference qualitative histology was calculated. RESULTS: An almost perfect agreement was achieved for both the intra- and inter-reproducibility of the histology and FFOCT qualitative grading (κ ≥ 0.91). A high and statistically significant level of agreement was measured between the histology and FFOCT grades (W = 0.95, P < 0.05). Strong and statistically significant correlations were measured between the quantitative results and the reference qualitative histology grades (ρ ≥ 0.75, P < 0.05). CONCLUSIONS: We have demonstrated that FFOCT is an alternative approach to conventional optical coherence tomography (OCT) that is as well adapted for the qualitative and quantitative assessment of human cartilage as the reference gold standard - histology. This study constitutes the first promising results towards developing a new diagnostic tool in the field of osteoarthritis.

Evaluation of the clinical benefit of an electromagnetic navigation system for CT-guided interventional radiology procedures in the thoraco-abdominal region compared with conventional CT guidance (CTNAV II): study protocol for a randomised controlled trial.

BACKGROUND: Interventional radiology includes a range of minimally invasive image-guided diagnostic and therapeutic procedures that have become routine clinical practice. Each procedure involves a percutaneous needle insertion, often guided using computed tomography (CT) because of its availability and usability. However, procedures remain complicated, in particular when an obstacle must be avoided, meaning that an oblique trajectory is required. Navigation systems track the operator's instruments, meaning the position and progression of the instruments are visualised in real time on the patient's images. A novel electromagnetic navigation system for CT-guided interventional procedures (IMACTIS-CT®) has been developed, and a previous clinical trial demonstrated improved needle placement accuracy in navigation-assisted procedures. In the present trial, we are evaluating the clinical benefit of the navigation system during the needle insertion step of CT-guided procedures in the thoraco-abdominal region. METHODS/DESIGN: This study is designed as an open, multicentre, prospective, randomised, controlled interventional clinical trial and is structured as a standard two-arm, parallel-design, individually randomised trial. A maximum of 500 patients will be enrolled. In the experimental arm (navigation system), the procedures are carried out using navigation assistance, and in the active comparator arm (CT), the procedures are carried out with conventional CT guidance. The randomisation is stratified by centre and by the expected difficulty of the procedure. The primary outcome of the trial is a combined criterion to assess the safety (number of serious adverse events), efficacy (number of targets reached) and performance (number of control scans acquired) of navigation-assisted, CT-guided procedures as evaluated by a blinded radiologist and confirmed by an expert committee in case of discordance. The secondary outcomes are (1) the duration of the procedure, (2) the satisfaction of the operator and (3) the irradiation dose delivered, with (4) subgroup analysis according to the expected difficulty of the procedure, as well as an evaluation of (5) the usability of the device. DISCUSSION: This trial addresses the lack of published high-level evidence studies in which navigation-assisted CT-guided interventional procedures are evaluated. This trial is important because it addresses the problems associated with conventional CT guidance and is particularly relevant because the number of interventional radiology procedures carried out in routine clinical practice is increasing. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01896219 . Registered on 5 July 2013.

Diffusion MRI: literature review in salivary gland tumors.

Surgical resection is currently the best treatment for salivary gland tumors. A reliable magnetic resonance imaging mapping, encompassing tumor grade, location, and extension may assist safe and effective tumor resection and provide better information for patients regarding potential risks and morbidity after surgical intervention. However, direct examination of the tumor grade and extension using conventional morphological MRI remains difficult, often requiring contrast media injection and complex algorithms on perfusion imaging to estimate the degree of malignancy. In addition, contrast-enhanced MRI technique may be problematic due to the recently demonstrated gadolinium accumulation in the dentate nucleus of the cerebellum. Significant developments in magnetic resonance diffusion imaging, involving voxel-based quantitative analysis through the measurement of the apparent diffusion coefficient, have enhanced our knowledge on the different histopathological salivary tumor grades. Other diffusion imaging-derived techniques, including high-order tractography models, have recently demonstrated their usefulness in assessing the facial nerve location in parotid tumor context. All of these imaging techniques do not require contrast media injection. Our review starts by outlining the physical basis of diffusion imaging, before discussing findings from diagnostic studies testing its usefulness in assessing salivary glands tumors with diffusion MRI.

Comparative study of computer-assisted total knee arthroplasty after opening wedge osteotomy versus after unicompartmental arthroplasty.

AIMS: The role of high tibial osteotomy (HTO) is being questioned by the use of unicompartmental knee arthroplasty (UKA) in the treatment of medial compartment femorotibial osteoarthritis. Our aim was to compare the outcomes of revision HTO or UKA to a total knee arthroplasty (TKA) using computer-assisted surgery in matched groups of patients. PATIENTS AND METHODS: We conducted a retrospective study to compare the clinical and radiological outcome of patients who underwent revision of a HTO to a TKA (group 1) with those who underwent revision of a medial UKA to a TKA (group 2). All revision procedures were performed using computer-assisted surgery. We extracted these groups of patients from our database. They were matched by age, gender, body mass index, follow-up and pre-operative functional score. The outcomes included the Knee Society Scores (KSS), radiological outcomes and the rate of further revision. RESULTS: There were 20 knees in 20 patients in each group. The mean follow-up was 4.1 years (2 to 18.7). The mean total KSS at last follow-up was 185.7 (standard deviation (sd) 5) in group 1 compared with 176.5 (sd 11) for group 2 (p = 0.003). The mean hip-knee-ankle angle was 180.2° (sd 3.2°) in group 1 and 179.0° (sd 2.2°) in group 2. No revision was required. CONCLUSION: We found that good functional and radiological outcomes followed revision of both HTO and UKA to TKA. Revision of HTO showed significantly better functional outcomes. These results need to be further investigated by a prospective randomised controlled trial involving a larger group of patients. Cite this article: Bone Joint J 2016;98-B:1620-4.

Role of computer-assisted surgery in osteotomies around the knee.

PURPOSE: The goal of this article is to present our experience on navigation for osteotomies around the knee and especially osteotomies for coronal deformities. The first computer-assisted osteotomy was performed in March 2001 and since that time more than 1000 osteotomies have been performed in our department. METHODS: All the osteotomies were performed with the Orthopilot® device (B-Braun-Aesculap, Tuttlingen, Germany). The main indication was for genu varum deformities but several cases were operated for genu valgum. The surgical procedure as well as the indications and the rationale for each osteotomy (high tibial osteotomy-HTO, double-level osteotomy-DLO, femoral osteotomy-FO) are addressed in the article. RESULTS: The results are focused on several papers published by the authors since more than 10 years. Regarding HTO for genu varum, the preoperative goal (HKA angle: 184° ± 2°) was reached in 96 % of cases and the difference was statistically significant compared to the non-navigated series (71 %: p < 0.05). Regarding DLO for genu varum, the preoperative goal was reached in 92.7 % for the HKA angle and in 88.1 % for the medial proximal tibial mechanical angle (MPTMA). Regarding genu valgum deformity, the preoperative goal was achieved in 86.2 % of cases for the HKA angle and 100 % of cases for the MPTMA. CONCLUSION: According to these results, one can say that, regardless the type of osteotomy, the procedure is reliable, reproducible and accurate. Since 15 years, all the osteotomies around the knee are navigated in our department. Provided that one uses a reproducible radiograph protocol, navigation allows to perform double-level osteotomies, both for genu varum and genu valgum, with optimal accuracy in order to avoid oblique joint line, which will be difficult to revise to TKA. LEVEL OF EVIDENCE: IV.

Long-term outcomes of tension band wiring with a single K-wire in Rockwood type IV/V acute acromio-clavicular dislocations: 25 cases.

BACKGROUND: Our objective was to evaluate the long-term functional and radiological outcomes of tension band wiring with a single K-wire for acute Rockwood types IV and V acromio-clavicular dislocation (ACD). METHODS: Single-centre cross-sectional non-randomised observational cohort study of 25 shoulders treated surgically between January 2002 and December 2004, in 25 patients, 23 males and 2 females, with a mean age of 35±11years (24-46). The evaluation criteria were the absolute and weighted Constant scores, QuickDASH score, subjective shoulder value (SSV), visual analogue scale (VAS) pain score at rest and during activities, and radiographic features in clinically symptomatic patients. RESULTS: Mean values were as follows: follow-up, 150±17months (133-167); absolute Constant score, 88±17 (71-105); weighted Constant score, 92.5±12.5 (80-105); QuickDASH, 15.5±7 (8.5-22.5); SSV, 88±17% (71-105); VAS pain score at rest, 0.2±0.7 (0-0.9); and VAS pain score while active, 1.4±2.3 (0-3.7). The weighted Constant score was less than 70% in only 8% of patients. Of the 17 patients for whom radiographs were obtained, 8 had acromio-clavicular osteoarthritis. Mean coraco-clavicular distance was 12.3±4.3mm (8-16.6) and mean acromio-clavicular distance was 5±5mm (0-10). The recurrence rate was 8%. CONCLUSION: Tension band wiring with a single K-wire for acute acromio-clavicular dislocation reliably provides good long-term functional outcomes. Recurrences are uncommon and few patients experience symptoms (8%). LEVEL OF EVIDENCE: IV, retrospective study.

Clinical and radiological outcomes with the Durom™ acetabular cup for large-diameter total hip arthroplasty: 177 implants after a mean of 80 months.

BACKGROUND: Large-diameter metal-on-metal hip prostheses are no longer used, but their outcomes after more than 5 years are unknown. We conducted a retrospective study with a 6.8-year mean follow-up to assess clinical outcomes after Durom™ cup implantation, including the dislocation rate, comparatively to the reference metal-on-polyethylene bearing. We determined the rate of failure ascribable to Durom™ cup use. We also looked for a sharp drop in the implant survival curve during the follow-up period and for factors associated with adverse reactions to metal debris (ARMDs). HYPOTHESIS: We hypothesised that clinical outcomes after Durom™ cup implantation were similar to those seen with a metal-on-polyethylene bearing, except for a lower rate of dislocation. PATIENTS AND METHODS: We included 177 consecutive THA procedures that were performed between 2005 and 2008 in 165 patients with a mean age of 57.6 ± 9.4 years (range, 31-76 years) and involved the implantation of a Durom™ cup, a femoral head greater than 36mm in diameter, and a PF(®) femoral stem (Zimmer, Etupes, France). The mini-posterior approach was used, with 2mm of acetabular overreaming in 82% of cases, a short femoral neck in 75% of cases, and a mean cup inclination of 34 ± 5° (range, 21-50°). RESULTS: Outcomes were assessed for 156 THA procedures in 146 patients after a mean follow-up of 6 years 8 months. The mean Postel-Merle d'Aubigné score improved from 9.7 ± 2.7 (range, 4-14) to 17.4 ± 1.7 (range, 15-18) and the mean Harris hip score from 45.2 ± 15.3 (range, 9-83) to 96.3 ± 7 (75-100). No episodes of dislocation were recorded. We identified 7 failures ascribable to the Durom™ cup including 6 due to ARMD and 1 to aseptic loosening. Implant survival after a mean of 80months was 95.5% (95% CI, 93.1-99.2), with no sharp drop in the survival curve. CONCLUSION: The Durom™ cup eliminates the risk of hip dislocation and produces similar functional outcomes to those seen with metal-on-polyethylene bearings after a mean follow-up of 80 months. Nevertheless, given the difficulty in predicting ARMD and hypersensitivity reactions, the Durom™ cup has been discarded and patients carrying it are monitored closely.

Fractures of the distal humerus operated on using the Lambda® plate: report of 75 cases at 9.5 years follow-up.

INTRODUCTION: The study sought to assess the functional results and complications of osteosynthesis using the Lambda(®) plate (Zimmer, Étupes, France) in treating fracture of the distal extremity of the humerus. MATERIALS AND METHODS: The initial series comprised 115 patients (116 fractures), treated between 1992 and 2008. Forty-one (mainly foreigners) were lost to follow-up. The final series thus comprised 74 patients (75 fractures): 44 female and 30 male, with a mean age of 46±23 years (range, 16-95 years), 22 (29%) being aged 65 years or over. According to AO classification, 22 of the fractures of the distal extremity of the humerus (29%) were diaphyseal-metaphyseal, corresponding to a particular grade of type A2, 12 (16%) were type A2 or A3, six (8%) type B, and 35 (47%) type C. Eight were open fractures: seven grade 1 and one grade IIa on Gustilo's classification. The Lambda(®) plate is an inverted Y shape, with a stem of up to ten holes and sectile arms that can be remodeled to adapt perfectly to the type of fracture and the shape of the distal end of the humerus. A posterior approach was used in all cases: in 26 cases, an extra-articular transolecranal approach and otherwise a transtricipital approach, either vertical for diaphyseal-metaphyseal fracture or inverted V for type-C fracture. RESULTS: Mean follow-up was 115±64 months (range, 24-227 months). There were no cases of infection, non-union of olecranial osteotomy or disassembly of the internal fixation; there was, on the other hand, one case of non-union of the lateral condyle and one of the distal extremity of the humerus, two cases of dysesthesia in the ulnar nerve territory and one in the radial nerve territory (following preoperative paralysis), and four cases of stiffness requiring surgical arthrolysis between 6 and 12 months postoperatively. At follow-up, mean active elbow flexion was 133°±13° (range, 90°-150°) and active extension -12°±14° (range, -45°-0°). Mean elbow flexion range of motion exceeded 100° in 58 patients (77%), was between 50° and 100° in 16 (21%) and was less than 50° in one. Mean Mayo Elbow Performance Score (MEPS) was 97±7 points (range, 40-100), and mean Quick DASH Score (converted as a score out of 100) was 10±18 (range, 0-54). There were 67 excellent results (MEPS, 90-100 points), five good (75-89), two moderate and one poor. The 35 type-C fractures displayed no significant differences from the series as a whole (P=1.24 for MEPS). CONCLUSION: Osteosynthesis using the Lambda(®) plate gave excellent medium-term results in terms of both fixation stability and recovery of elbow function after fracture of the distal extremity of the humerus, even in elderly osteoporotic patients. LEVEL OF EVIDENCE: Level IV: retrospective study.