A 10-day theta burst stimulation intervention facilitates the clinical rehabilitation of patients following an isolated limb fracture: A longitudinal SHAM-controlled pilot study.

OBJECTIVE: We investigated if theta burst stimulation (TBS) could enhance recovery by reducing key symptoms when implemented acutely post-fracture in participants with an isolated upper limb fracture (IULF). METHODS/DESIGN: This was a pilot study with a randomized matched pair, sham-controlled, participant-blind design of a 10-day prolonged continuous TBS protocol. Two main groups were included: I) participants with IULF receiving active TBS; and II) patients with IULF receiving SHAM/placebo. Another group (III) of healthy individuals were the reference group. Disability and pain intensity were collected through questionnaires (DASH & NRA) at three timepoints (baseline; 72 h post-intervention & 3 months post-injury). Group III completed the baseline assessment. RESULTS: 79 participants were enrolled. Individuals in the ACTIVE and SHAM groups had similar baseline measures. For disability, the interaction between Intervention and Time approached significance (F = 2.33; p = 0.11), whereas it was significant for pain (F = 3.42; p = 0.04). At 3 months post-injury, the ACTIVE group reported reduced disability (F = 4.71; p = 0.04) and pain (F = 5.84; p = 0.02) at three months post-injury compared to the SHAM group, with clinical measures from ACTIVE group being like controls. CONCLUSIONS: In IULF patients, a 10-day TBS intervention implemented acutely post-trauma had beneficial effects on symptoms of functional recovery and pain at 3 months post-trauma.

Validity, reliability and responsiveness of a French translation of the Western Ontario Osteoarthritis of the Shoulder index (WOOS).

INTRODUCTION: While several general questionnaires can be used to evaluate shoulder conditions, very few tools specifically evaluate the impact of shoulder osteoarthritis. The WOOS (Western Ontario Osteoarthritis of the Shoulder index) is a patient-reported outcome measure with excellent psychometric properties intended for patients suffering from shoulder osteoarthritis. Unfortunately, there is no validated French version of this questionnaire. OBJECTIVE: Produce a validated French version of the WOOS that is suitable for the Francophone populations of Europe and North America. MATERIAL AND METHODS: A validated protocol was used to create a French version of the WOOS (WOOS-Fr). Included were patients whose first language was French, who could read French and who had shoulder osteoarthritis destined for treatment (surgical treatment = arthroplasty). The WOOS-Fr was compared to the F-QuickDASH-D/S (Disability of the Arm, Shoulder and Hand - French translation) to assess its validity. Reliability and responsiveness were also analyzed. RESULTS: A French version of the WOOS (WOOS-Fr) was accepted by a multinational committee. The WOOS-Fr was validated in 71 French-speaking subjects. A strong positive correlation was found between the WOOS-Fr and the F-QuickDASH-D/S during the initial evaluation. The intra-class correlation (ICC) of the total WOOS-Fr score indicated good reliability between the initial WOOS and the 1-week WOOS (ICC: 0.84; 95% CI: [0.767; 0.896]; p value: <.001) in 57 patients. The responsiveness between the initial WOOS-Fr and at 1 year postoperative was high in the 36 operated patients (standardized mean response of 1.95). DISCUSSION: A French translation of the WOOS questionnaire was created and validated for use in French-speaking populations. This questionnaire will make it easier to evaluate the psychometric results of patients with shoulder osteoarthritis in Francophone countries. LEVEL OF EVIDENCE: III; multicenter cohort study.

A systematic scoping review of the latest data on orthobiologics in the surgical treatment of non-union.

INTRODUCTION: Recent studies have shown a growing concern regarding the cost-effectiveness and the lack of supporting data for the biologic agents that are being increasingly used in the orthopedic field. Our aim was to conduct a systematic scoping review of recent publications (last five years) on the use of orthobiologics to treat fracture non-union and summarize the latest available data. PATIENTS AND METHODS: The inclusion criteria for this review were articles published in English, from 2016 to 2022, and focusing on the use of orthobiologics for the surgical treatment of non-union. Searches were conducted in March 2023 using Pubmed/MEDLINE and Embase. Studies on spinal fusion or gene therapy were excluded. Reviews, case reports with five cases or less, conference proceedings, preliminary reports, pediatric or non-human studies were excluded as well. RESULTS: The search found 1807 articles, 15 were eligible after PRISMA checklist and exclusions. The evidence was heterogenous and there was only one level II RCT. Recent data suggests that bone morphogenic protein (BMP-2) products could be effective for septic and aseptic tibial non-unions. However, the evidence was not conclusive regarding BMP-7, plasma rich platelets (PRP), stem cells or demineralized bone matrix (DBM). DISCUSSION: Every non-union case is different in terms of bone defect, biology, mechanical stability, surgical technique and host factors, which contributes to the conflicting reports on the efficacy of orthobiologics in the literature. We might never see a level 1, high powered and robust study defining the efficacy, safety profile and cost-effectiveness of such products. LEVEL OF EVIDENCE: IV.

A novel fragment specific classification of complex olecranon fractures: 3-dimensional model design, radiological validation, and proposed surgical algorithm.

BACKGROUND: Current classifications for proximal ulna fracture patterns rely on qualitative data and cannot inform surgical planning. We propose a new classification system based on a biological and anatomical stress analysis. Our hypothesis is that fragment types in complex fractures can be predicted by the tendon and ligament attachments on the proximal ulna. METHODS: First, we completed a literature review to identify quantitative data on proximal ulna soft tissue attachments. On this basis, we created a 3-dimensional model of ulnar anatomy with SliceOMatic and Catia V5R20 software and determined likely locations for fragments and fracture lines. The second part of the study was a retrospective radiological study. A level-1 trauma radiological database was used to identify computed tomography scans of multifragmentary olecranon fractures from 2009 to 2021. These were reviewed and classified according to the "fragment specific" classification and compared to the Mayo and the Schatzker classifications. RESULTS: Twelve articles (134 elbows) met the inclusion criteria and 7 potential fracture fragments were identified. The radiological study included 67 preoperative computed tomography scans (mean 55 years). The fragments identified were the following: posterior (40%), intermediate (42%), tricipital (100%), supinator crest (25%), coronoid (18%), sublime tubercle (12%), and anteromedial facet (18%). Eighteen cases (27%) were classified as Schatzker D (comminutive) and 21 (31%) Mayo 2B (stable comminutive). Inter-rater correlation coefficient was 0.71 among 3 observers. CONCLUSION: This proposed classification system is anatomically based and considers the deforming forces from ligaments and tendons. Having a more comprehensive understanding of complex proximal ulna fractures would lead to more accurate fracture evaluation and surgical planning.

Validity, reliability and responsiveness of the French translation of the Patient-Rated Wrist Evaluation Questionnaire (PRWE).

INTRODUCTION: The patient-rated wrist evaluation questionnaire (PRWE) is a specific wrist questionnaire, developed in Canada that has been validated and proved reliable and sensitive. It assesses pain and function. Unfortunately, there was no validated French-language version. It is important that a translation should be methodologically rigorous, as both linguistic and cultural factors come into play. OBJECTIVE: To produce a French-language version of the PRWE, culturally adapted to the French-speaking populations of Europe and North America. MATERIALS AND METHODS: A validated protocol was used to produce a French-language version of the PRWE (PRWE-Fr) that would be culturally acceptable for the French-speaking populations of Europe and North America. Reliability and responsiveness analyses were performed and PRWE-Fr scores were compared to F-QuickDASH-D/S (French translation of short-form Disabilities of the Arm, Shoulder and Hand-Disability/Symptoms) scores to assess validity. RESULTS: A French-language version of the PRWE (PRWE-Fr) was accepted by a multinational committee, then validated in 65 French-speaking subjects, divided into 2 groups for analyses. A strong positive correlation was found between PRWE-Fr and F-QuickDASH-D/S scores. Comparison of results between two PRWE-Fr sessions at a 1-week interval found a very strong correlation (ρ=0.93; r2=0.868; p<0.001). The intraclass correlation coefficient for total PRWE-Fr score demonstrated excellent reliability (ICC: 0.93; 95% CI: [0.859; 0.969]; p<0.001). Responsiveness analysis revealed greater sensitivity to change than for the F-QuickDASH-D/S (standardized response mean [SRM], 1.14 versus 1.04 respectively). DISCUSSION: A French-language version of the PRWE was produced and validated for use in French-speaking populations. It should facilitate evaluation of results in French-speaking settings, collaboration in multinational studies and comparison between studies performed in different countries. LEVEL OF EVIDENCE: II; Multicenter cohort study.

Corrective Open-wedge Valgus Proximal Humerus Lengthening Osteotomy. Technique and Case Series.

Symptomatic varus malunion after proximal humeral fractures is associated with weakness and painful limitation of shoulder range of motion. When there is conformity of the articular surface and no avascular necrosis, a head-preserving procedure is best indicated. Arthroscopic arthrolysis, subacromial decompression, and tuberoplasty have been described for the treatment of mild deformity. In cases with more severe deformity, corrective extracapsular lateral closing wedge valgus osteotomy has been reported as a reliable treatment option, in terms of both pain relief and improved function. While this procedure adequately restores rotator cuff tensioning, it is associated with a shortening of the lever arm to the deltoid muscle, secondary to a loss of humeral length. We describe our technique and results with a vascular-sparing, medial open-wedge osteotomy, using a structural allograft and lateral locking plate. In our opinion, this procedure is safe and effective, with the potential to improve functional outcomes in young and active patients.

Variable flip angle T1 mapping and multi-echo T2 and T2* mapping magnetic resonance imaging sequences allow quantitative assessment of canine lumbar disc degeneration.

Magnetic resonance imaging is the gold standard for diagnosing intervertebral disc (IVD) degeneration in dogs. However, published methods for quantifying severity or progression of IVD degeneration are currently limited. Mapping MRI sequences are used in humans for quantifying IVD degeneration but have rarely been applied in dogs. The objective of this prospective, method comparison study was to evaluate variable flip angle T1 mapping and multiecho T2 and T2* mapping as methods for quantifying canine lumbar IVD degeneration in twenty canine patients without clinical signs of spinal disease. Ventral and dorsal lumbar IVD widths were measured on radiographs, and lumbar IVDs were assigned a qualitative Pfirrmann grade based on standard T2-weighted sequences. T1, T2, and T2* relaxation times of the nucleus pulposus (NP) were measured on corresponding maps using manual-drawn ROIs. Strong intra- and interrater agreements were found (P < 0.01) for NP relaxation times. Radiographic IVD widths and T1, T2, and T2* mapping NP relaxation times were negatively correlated with Pfirrmann grading (P < 0.01). Significant differences in T1 NP relaxation times were found between Pfirrmann grade I and the other grades (P < 0.01). Significant differences in T2 and T2* NP relaxation times were found between grade I and the other grades and between grades II and III (P < 0.01). Findings indicated that T1, T2, and T2* MRI mapping sequences are feasible in dogs. Measured NP relaxation times were repeatable and decreased when Pfirrmann grades increased. These methods may be useful for quantifying the effects of regenerative treatment interventions in future longitudinal studies.

Impact of vitamin C on the reduction of opioid consumption after an emergency department visit for acute musculoskeletal pain: a double-blind randomised control trial protocol.

INTRODUCTION: Recent evidence has shown that vitamin C has some analgesic properties in addition to its antioxidant effect and can, therefore, reduce opioid use during recovery time. Vitamin C analgesic effect has been explored mostly during short-term postoperative context or in disease-specific chronic pain prevention, but never after acute musculoskeletal injuries, which are often seen in the emergency department (ED). The protocol's primary aim is to compare the total morphine 5 mg pills consumed during a 2-week follow-up between patients receiving vitamin C or a placebo after ED discharge for an acute musculoskeletal pain complaint. METHODS AND ANALYSIS: We will conduct a two-centre double-blind randomised placebo-controlled trial with 464 participants distributed in two arms, one group receiving 1000 mg of vitamin C two times a day for 14 days and another one receiving a placebo. Participants will be ≥18 years of age, treated in ED for acute musculoskeletal pain present for less than 2 weeks and discharged with an opioid prescription for home pain management. Total morphine 5 mg pills consumed during the 2-week follow-up will be assessed via an electronic (or paper) diary. In addition, patients will report their daily pain intensity, pain relief, side effects and other types of pain medication or other non-pharmacological approach used. Three months after the injury, participants will also be contacted to evaluate chronic pain development. We hypothesised that vitamin C, compared with a placebo, will reduce opioid consumption during a 14-day follow-up for ED discharged patients treated for acute musculoskeletal pain. ETHICS AND DISSEMINATION: This study has received approval from the Ethics Review Committee from the 'Comité d'éthique de la recherche du CIUSSS du Nord-de-l'Île-de-Montréal (No 2023-2442)'. Findings will be disseminated through scientific conferences and peer-reviewed journal publication. The data sets generated during the study will be available from the corresponding author on reasonable request. TRIAL REGISTRATION NUMBER: NCT05555576 ClinicalTrials.Gov PRS.

The POSI study: gender differences in 94 cases of postoperative shoulder surgery infection: results of a 7-year retrospective multicenter study.

BACKGROUND: Contrary to lower limb infection, POstoperative Shoulder surgery Infection (POSI) often involves Cutibacterium acnes. Our aim was to describe patient characteristics and pathogens retrieved in POSI to guide initial empiric antibiotic selection with suspected infection during revision. We also compared microorganisms in infection following trauma, arthroplasty (AP), and arthroscopy (AS). METHODS: A multicenter retrospective study from 2010 to 2016 reviewed laboratory databases and medical records to identify patients with a previous shoulder surgery and a confirmed shoulder infection. The following procedures were included: AP, AS, fracture fixation (FF), and another open surgery (OS). A confirmed shoulder infection was defined as 2 positive cultures or more of the same microorganism, or clear clinical infection with 1 positive culture or more. RESULTS: Among the 5 hospitals and 28 surgeons involved, 94 POSI cases were identified. Mean age was 59 years at index surgery (range: 22-91) with a majority of men (n = 70, 74%). Among POSI cases, AP was the most common index surgery (n = 41), followed by FF (n = 27), AS (n = 16), and OS (n = 10). The median time between index surgery and the first positive sample was 5 months and the mean was 23 months (minimum 6 days to maximum 27 years), illustrating a positively skewed distribution. Cutibacterium spp were identified in 64 patients (68%), including 59 C acnes patients (63%), which was the most frequent germ in all 4 surgical groups. In 86% of cases, C acnes was identified at the first revision. The other 2 most common germs were Staphylococcus epidermidis and Staphylococcus aureus, with 29% and 17%, respectively. Polymicrobial infection was present in 30% of patients. Gender analysis revealed that C acnes was twice as frequent in men (male = 52 of 70, female = 7 of 24; P < .001). S epidermidis was more prevalent in women (n = 11; 46%) compared with men (n = 16; 21%) (P = .032). C acnes infection was most frequent in arthroscopic surgery (n = 14; 70%, P = .049). S epidermidis was 3 times more prevalent in chronic than in acute cases. CONCLUSION: Empiric antimicrobial therapy following POSI, while waiting for culture results, should cover C acnes, S epidermidis, and S aureus. There is a significant gender difference regarding POSI culture results. C acnes is more frequent in men, but should still be covered in women as it was found in 29% of cases.

Traumatic brain injuries are ignored or discriminated in prospective clinical trials on shoulder fractures: a systematic review.

PURPOSE: Current literature suggests a significant epidemiological association between traumatic brain injury (TBI) and proximal upper limb fractures in addition to major clinical consequences. A systematic review was conducted to assess how TBI is taken into consideration in interventional studies on shoulder fractures. METHODS: The following data sources were used: MEDLINE, EMBASE, EBM Reviews, CINAHL, and OpenGrey databases. Study selection included interventional randomized clinical trials and prospective cohort studies on shoulder fractures published in English or French between 2008 and 2020. Studies on pathologic fractures, chronic fracture complications, nonhuman subjects, and biomechanics were excluded. Articles were reviewed by two independent authors according to the PRISMA guidelines. Baseline characteristics, exclusion criteria, and input relevant to TBI were recorded. Methodological quality was assessed with the Cochrane risk of bias tool for randomized clinical trials and the Newcastle-Ottawa Scale for cohort studies. RESULTS: One-hundred-thirteen studies met the inclusion criteria. None discussed the possible impact of TBI on their results. Only three (2.7%) studies considered TBI relevant and included these patients in their cohort. Furthermore, 43/113 (38.1%) excluded patients with injuries or mechanisms strongly related to traumatic brain injuries: head injuries (4); moderate and/or severe TBI (7); high energy traumas (3); Polytrauma subjects (33). CONCLUSION: TBI are ignored or discriminated in prospective clinical trials on shoulder fractures. The exclusion of these cases impacts generalizability as their prevalence is significant. Considering the major impact of TBI on important outcomes, its presence should always be assessed to ensure high quality evidence. LEVEL OF EVIDENCE: Systematic Review, Therapeutic Level II.

Phone Administration of the Western Ontario Shoulder Instability Index Is More Reliable Than Administration via Email.

BACKGROUND: The Western Ontario Shoulder Instability (WOSI) questionnaire is a 21-item questionnaire to evaluate quality of life in patients with shoulder instability. Completing the questionnaire is time-consuming because each item is evaluated on a visual analog scale. Telephone or email versions of the score are appealing alternatives to administering it during the standard in-person patient visit; however, their validity and reliability remain unknown. QUESTIONS/PURPOSES: (1) Does the numerical scale (NS) version of the WOSI correlate with the original WOSI and Quick-DASH? (2) Do telephone and email administration of the NS-WOSI have good reliability and consistency? (3) Compared with the original WOSI form, does the NS form lead to faster completion for patients and quicker data extraction for researchers? METHODS: Between 2014 and 2019, 50 patients with a documented history of shoulder dislocation with persistent symptomatic shoulder instability, whether anterior, posterior, or multidirectional; patients scheduled for surgery; and patients with traumatic or nontraumatic injuries were prospectively recruited from the outpatient clinic of two university hospitals acting as Level 1 trauma centers and sports traumatology tertiary referral centers. The median (IQR) age was 28 years (24 to 36), and 80% (40 of 50) were men. Most (52% [26 of 50]) patients had two to five lifetime shoulder dislocations. Validity of the NS-WOSI was assessed using the Pearson correlation coefficient during an in-person visit; the original WOSI questionnaire (or its previously validated French-language version), NS-WOSI, and Quick-DASH questionnaires were administered in a random order. After a minimum 7-day interval, 78% (39 of 50) of patients completed the phone interview, and 74% (37 of 50) of patients completed the email version of the NS-WOSI score to evaluate NS-WOSI's reliability using the intraclass correlation coefficient (ICC), which was interpreted as poor (< 0.5), moderate (0.50-0.75), strong (0.75-0.90), and very strong (> 0.90). The standard error of measurement (SEM) was used to evaluate variability around the true score, with a low value indicating a high reliability. The 95% minimal detectable change (MDC 95% ) was calculated to evaluate the minimal change in score that was not related to measurement errors. Lastly, the Cronbach alpha was used to assess internal consistency (intercorrelation strength), where a value > 0.70 was considered good. The time needed for the patient to complete the various versions and for researchers to extract data was recorded. RESULTS: The NS-WOSI score was very strongly correlated with the original WOSI score (r = 0.96 [95% confidence interval (CI) 0.93 to 0.98]; p < 0.001). Although telephone-acquired and email-acquired data for the NS-WOSI questionnaires were correlated with the NS-WOSI (telephone r = 0.91 [95% CI 0.83 to 0.95]; p < 0.001; email r = 0.84 [95% CI 0.71 to 0.91]; p < 0.001), the ICC was higher for telephone interviews (0.92 [95% CI 0.86 to 0.96] versus email 0.80 [95% CI 0.64 to 0.89]), indicating that although both had good reliability, the phone interview was more suitable. The phone interview was also preferable to email regarding SEM (3% [52 of 2100 points] versus 6% [132 of 2100 points]) and the MDC 95% (7% [144 of 2100 points] versus 17% [366 of 2100 points]). The 95% CI of the MDC acquired by email was superior to the reported minimum clinically important difference for the original WOSI (7% [152 of 2100 points]), meaning that an error of measurement could wrongly be interpreted as a clinically significant change in score. Internal consistency was deemed good, with a Cronbach alpha of 0.96 (95% CI 0.92 to 98) and 0.89 (95% CI 0.79 to 0.94) for NS-WOSI telephone and email, respectively. The time to complete the NS-WOSI was reduced compared with the original WOSI (221 ± 153 seconds versus 266 ± 146 seconds, mean difference -45 seconds [95% CI -72 to -12]; p = 0.009). Lastly, data extraction was faster (62 ± 15 seconds versus 209 ± 52 seconds, mean difference -147 seconds [95% CI -164 to -130]; p < 0.001) with the NS-WOSI than with the original WOSI. CONCLUSION: The NS-WOSI in person, by telephone, or by email is a valid, reliable, and timesaving alternative to the original WOSI questionnaire. However, the reliability of data acquisition by telephone interviews was superior to that of email. CLINICAL RELEVANCE: Given that there were no important differences in performance for the NS-WOSI, regardless of whether it was administered in person or by phone, we suggest that physicians use both interchangeably based on patient convenience. However, we do not recommend using the email version, especially for research purposes, since it was not as reliable when compared with in-person administration. The responsiveness of the modified NS-WOSI, as well as factors influencing response rates to phone interview, are questions that remain to be explored.

Lipid nanocapsules for intracellular delivery of microRNA: A first step towards intervertebral disc degeneration therapy.

Approximately 40% of cases of lower back pain are caused by disc degeneration disease (DDD). It is well established that microRNA (miR) dysregulation is a key player in various diseases, and its impact on DDD has recently been highlighted. RNAi (miR in particular) is increasingly being considered as a novel therapeutic tool. However, free miR is degraded rapidly in vivo, and its protection is thus a prerequisite. Nanoparticular platforms, such as lipid nanocapsules (LNC), could be specifically adapted for miR delivery, allowing the transfer and release of miR in the cell cytoplasm. The objective of the current study was to formulate and characterize miR-loaded LNC to establish their in vitro potential (cell internalization, bioactivity) as well as to determine the safety and feasibility of in situ intervertebral disc (IVD) injection of miR LNC in a healthy sheep model. Using a miR library, miR-155 was clearly identified as being involved in the DDD process and was selected for further assessment. miR-155-loaded LNC (miR-155 LNC) were successfully formulated using a phase inversion process, with the addition of lipoplexes in the cooling step. Following purification, miR-155 LNC were fully characterized, and the optimized formulation had an average diameter of 75 nm, a polydispersity index below 0.1, and a positive zeta potential. By fluorescence spectroscopy, an encapsulation efficiency (EE) of 75.6% and a drug loading (DL) of 0.6% were obtained, corresponding to a sufficient amount of miR per mL of LNC to potentially have a biological effect. The sustained release of miR-155 from LNC was demonstrated compared with free miR-155: only 22% was released after 2 h and 58% after 24 h. miR-155 protection against endonuclease degradation by LNC was confirmed by gel electrophoresis, a sine qua non condition for it to be administered in vivo. Cell viability assays were performed on human adipose stromal cells (hASCs) and ovine Nucleus pulposus cells (oNP), and a cytotoxicity of <30% was obtained at the considered concentrations. Additionally, miR-155 LNC cell internalization was demonstrated by flow cytometry and confocal imaging. Moreover, downregulation of total ERK1/2 in hASCs and oNP cells, after miR-155 LNC treatment, was demonstrated by Western blot and quantitative reverse-transcription PCR (qRT-PCR), thus confirming maintenance of its bioactivity after formulation and internalization. Finally, the feasibility and safety of miR-155 LNC in situ injection (compared to control groups: blank LNC and sham condition) was demonstrated in healthy sheep by imaging (MRI and T2wsi measurement) and histology (Boos' scoring) analysis. T2wsi was measured, and no significant difference was observed three months after the injection between the different conditions. No histological impact was observed, with no significant difference in Boos' scoring between the different conditions. All these results suggest LNC may be a potent strategy for the encapsulation and delivery of miR (particularly miR-155) and can be considered as a first step towards IVD regenerative medicine.

Comparison of MRI T1, T2, and T2* mapping with histology for assessment of intervertebral disc degeneration in an ovine model.

An easy, reliable, and time-efficient standardized approach for assessing lumbar intervertebral disc (IVD) degeneration with relaxation times measurements in pre-clinical and clinical studies is lacking. This prospective study aims to determine the most appropriate method for lumbar IVD degeneration (IDD) assessment in sheep by comparing three quantitative MRI sequences (variable-flip-angle T1 mapping, and multi-echo T2 and T2* mapping), correlating them with Pfirrmann grading and histology. Strong intra- and interrater agreements were found for Nucleus pulposus (NP) regions-of-interest (ROI). T1, T2, and T2* mapping correlated with Pfirrmann grading and histological scoring (p < 0.05) except for the most ventral rectangular ROI on T2 maps. Correlations were excellent for all of the T1 ROIs and the T2* NP ROIs. Highly significant differences in T1 values were found between all Pfirrmann grades except between grades I/II and between grades III/IV. Significant differences were identified in the T2 and the T2* values between all grades except between grades I/III. T1, T2, and T2* relaxation times measurements of the NP are an accurate and time-efficient tool to assess lumbar IDD in sheep. Variable-flip-angle T1 mapping may be further considered as a valuable method to investigate IDD and to assess the efficacy of regenerative treatments in longitudinal studies.

Relevance of Sleep Disturbances to Orthopaedic Surgery: A Current Concepts Narrative and Practical Review.

➤: Sleep disturbances can increase the risk of falls and motor vehicle accidents and may reduce bone density. ➤: Poor sleep can lead to worse outcomes after fracture, such as chronic pain and delayed recovery. ➤: Orthopaedic surgeons can play an important role in the screening of sleep disorders among their patients.

Real-Time and Dynamically Consistent Estimation of Muscle Forces Using a Moving Horizon EMG-Marker Tracking Algorithm-Application to Upper Limb Biomechanics.

Real-time biofeedback of muscle forces should help clinicians adapt their movement recommendations. Because these forces cannot directly be measured, researchers have developed numerical models and methods informed by electromyography (EMG) and body kinematics to estimate them. Among these methods, static optimization is the most computationally efficient and widely used. However, it suffers from limitation, namely: unrealistic joint torques computation, non-physiological muscle forces estimates and inconsistent for motions inducing co-contraction. Forward approaches, relying on numerical optimal control, address some of these issues, providing dynamically consistent estimates of muscle forces. However, they result in a high computational cost increase, apparently disqualifying them for real-time applications. However, this computational cost can be reduced by combining the implementation of a moving horizon estimation (MHE) and advanced optimization tools. Our objective was to assess the feasibility and accuracy of muscle forces estimation in real-time, using a MHE. To this end, a 4-DoFs arm actuated by 19 Hill-type muscle lines of action was modeled for simulating a set of reference motions, with corresponding EMG signals and markers positions. Excitation- and activation-driven models were tested to assess the effects of model complexity. Four levels of co-contraction, EMG noise and marker noise were simulated, to run the estimator under 64 different conditions, 30 times each. The MHE problem was implemented with three cost functions: EMG-markers tracking (high and low weight on markers) and marker-tracking with least-squared muscle excitations. For the excitation-driven model, a 7-frame MHE was selected as it allowed the estimator to run at 24 Hz (faster than biofeedback standard) while ensuring the lowest RMSE on estimates in noiseless conditions. This corresponds to a 3,500-fold speed improvement in comparison to state-of-the-art equivalent approaches. When adding experimental-like noise to the reference data, estimation error on muscle forces ranged from 1 to 30 N when tracking EMG signals and from 8 to 50 N (highly impacted by the co-contraction level) when muscle excitations were minimized. Statistical analysis was conducted to report significant effects of the problem conditions on the estimates. To conclude, the presented MHE implementation proved to be promising for real-time muscle forces estimation in experimental-like noise conditions, such as in biofeedback applications.

Collateral effects of targeting the nucleus pulposus via a transpedicular or transannular surgical route: a combined X-ray, MRI, and histological long-term descriptive study in sheep.

PURPOSE: In the context of regenerative medicine strategies, based in particular on the injection of regenerative cells, biological factors, or biomaterials into the nucleus pulposus (NP), two main routes are used: the transpedicular approach (TPA) and the transannular approach (TAA). The purpose of our study was to compare the long-term consequences of the TPA and the TAA on intervertebral disc (IVD) health through a longitudinal follow-up in an ovine model. METHODS: The TPA and the TAA were performed on 12 IVDs from 3 sheep. Six discs were left untreated and used as controls. The route and injection feasibility, as well as the IVD environment integrity, were assessed by MRI (T2-weighted signal intensity), micro-CT scan, and histological analyses (Boos' scoring). The sheep were assessed at 1, 3, and 7 months. RESULTS: Both the TPA and the TAA allowed access to the NP. They both induced NP degeneration, as evidenced by a decrease in the T2wsi and an increase in the Boos' scores. The TPA led to persistent end-plate defects and herniation of NP tissue (Schmorl's node-like) after 7 months as well as the presence of osseous fragments in the NP. CONCLUSIONS: The TPA induced more severe lesions in IVDs and vertebrae compared to the TAA. The lesions induced by the TPA are reason to consider whether or not this route is optimal for studying IVD regenerative medicine approaches.

Novel Technical Factors Affecting Proximal Humerus Fixation Stability.

OBJECTIVES: Intra-articular screw cut-out is a common complication after proximal humerus fracture (PHF) fixation using a locking plate. This study investigates novel technical factors associated with mechanical failures and complications in PHF fixation. DESIGN: A retrospective radiological study. SETTING: Level 1 trauma center. PATIENTS/PARTICIPANTS: Clinical and radiological data from consecutive PHF patients treated between January 2007 and December 2013 were reviewed. INTERVENTION: Open reduction and internal fixation with the Synthes Philos locking plate. MAIN OUTCOME MEASUREMENTS: Postoperative radiographs were assessed for quality of initial reduction, humeral head offset, screw length, number and position, restoration of medial calcar support or the presence of calcar screws, and intra-articular screw perforations. Using SliceOMatic software, we validated a method to accurately identify screws of 45 mm or longer on AP radiographs. Follow-up radiographs were reviewed for complications. RESULTS: Among 110 patients included [mean age 60 years, 78 women (71%), follow-up 2.5 years] and the following factors were associated with a worse outcome. (1) Screws >45 mm in proximal rows [Odds Ratio (OR) = 5.3 for screw cut-out); (2) lateral translation of the humeral diaphysis over 6 mm (OR = 2.7 for loss of reduction); (3) lack in medial support by bone contact (OR = 4.9 for screw cut-out); (4) varus reduction increased the risk of complications (OR = 4.3). CONCLUSION: The importance of reduction and calcar support in PHF fixation is critical. This study highlights some technical factors to which the surgeon must pay attention: avoid varus reduction, maximize medial support, avoid screws longer than 45 mm in the proximal rows, and restore the humeral offset within 6 mm or less. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Greater trochanteric pain after primary total hip replacement, comparing the anterior and posterior approach: A secondary analysis of a randomized trial.

BACKGROUND: Greater trochanteric pain (GTP) after total hip replacement is a common cause of residual lateral hip pain, regardless of the approach used. The goal of our study was to evaluate GTP after a direct anterior approach (DAA) compared to a posterior approach (PA) as well as the clinical outcomes of both approaches and answer the following: 1) What is the incidence of trochanteric pain after primary THA with two different surgical approaches? 2) What is the functional outcome of patients with GTP? 3) What proportion of patients with GTP resort to peritrochanteric injections? HYPOTHESIS: Our hypothesis is that GTP is present with both approaches but satisfaction is lower with the PA. PATIENTS AND METHODS: A secondary analysis of a previously published clinical trial with 55 total hip arthroplasty patients randomized in one of two surgical approaches: 27 patients underwent the anterior modified Hueter approach, while the other group of 28 patients were operated using the posterior approach. Study outcomes were Modified Harris Hip Score (MHHS), satisfaction score, pain when lying on the affected side, and requiring an injection. Hip offset, femur lateralization and leg lengthening were measured before and after surgery. RESULTS: Forty-five patients were available for complete follow-up at a mean of 62 months (range: 48-74). The incidence of GTP was higher in the posterior approach [PA: 6/21 (29%) vs DAA 4/24 (17%)) (p=0.3). Patients operated through a PA experienced more pain [5/21 (24%) of patients; VAS=mean 5.3] when lying on their operated side, compared to DAA patients [2/24 (8%) of patients; VAS=mean 2) (p=0.2)]. However, MHHS, patient satisfaction with surgery, radiological assessment for hip offset, femur lateralization or leg lengthening, and injections required were similar for both approaches. Overall, satisfaction and functional outcome with surgery was significantly lower in GTP patients, regardless of the approach. CONCLUSIONS: GTP impacts patient satisfaction and functional outcome in total hip arthroplasty patients. PA patients reported more trochanteric pain than DAA patients, which affected their clinical outcome. LEVEL OF EVIDENCE: III.

Outcomes of surgical fixation of greater tuberosity fractures: A systematic review.

BACKGROUND: Isolated greater tuberosity fractures account for up to a fifth of all proximal humeral fractures. There have been several retrospective cohort studies and case series reporting outcomes after treatment of this pathology. This study aims to report on the clinical outcomes of surgically treated isolated greater tuberosity fractures, as well as diagnostic workup and complications associated with fracture fixation. METHODS: A systematic review was performed under PRISMA guidelines to identify studies that reported the results or clinical outcomes of isolated greater tuberosity fracture. The searches were performed using MEDLINE through PubMed, the Elsevier Embase database, and the Cochrane Database of Systematic Reviews. RESULTS: Sixteen studies met inclusion criteria comprising 345 patients and 345 shoulders. The mean age was 52.9 years and mean follow-up was 3.4 months. The mean postoperative American Shoulder and Elbow Surgeon Score, the most frequently utilized patient reported outcome measure across studies, was 90.1% of ideal maximum. All studies used standard shoulder radiographs in their initial workup and most commonly referred to a minimum of 5mm displacement as an indication for surgery. Fifty five percent of patients were treated using open fixation and 35.9 with arthroscopic fixation. Ninety three percent of patients were able to return to work. A total of fifty-two (15.1%) complications were reported in the included studies. CONCLUSIONS: The current literature describes overall satisfactory functional outcomes and minimal occupational morbidity following either open or arthroscopic fixation of isolated greater tuberosity fractures despite a notable rate of complications. LEVEL OF EVIDENCE: IV, systematic review.