Orientation of the Scapula in the Standing Position.

OBJECTIVES: A new ultrasound-based device is proposed to non-invasively measure the orientation of the scapula in the standing position to consider this parameter for Total Shoulder Arthroplasty. The aim of this study was to assess the accuracy and reliability of this device. METHODS: Accuracy was assessed by comparing measurements made with the ultrasound device to those acquired with a three-dimensional (3D) optical localization system (Northern Digital, Canada) on a dedicated mechanical phantom. Three users performed 10 measurements on three healthy volunteers with different body mass (BMI) indices to analyze the reliability of the device by measuring the intra and interobserver variabilities. RESULTS: The mean accuracy of the device was 0.9°± 0.7 (0.01-3.03), 1.3°± 0.8 (0.03-4.55), 1.9°± 1.5 (0.05-5.76), respectively, in the axial, coronal, and sagittal planes. The interobserver and intraobserver variabilities were excellent whatever the BMI and the users experience. CONCLUSIONS: The device is accurate and reliable enough for the measurement of the scapula orientation in the standing position.

Laparoscopic treatment of fourteen cases of pelvic ring disruption: a case series.

PURPOSE: Open surgical approaches for the treatment of anterior pelvic arc lesions are associated with several complications. We present the first retrospective descriptive case series on the use of laparoscopy as an alternative. METHODS: This descriptive, retrospective, single-centre study enrolled all patients who underwent laparoscopy for the treatment of pelvic ring disruption between May 2020 and March 2022. The primary outcome was the procedure failure rate based on conversion to open surgery. Secondary outcomes were the duration of the surgical procedure, x-ray exposure, length of hospitalisation, postoperative pain assessment, and functional scores at the last follow-up. RESULTS: The study included two females and 12 males. The mean age of the study participants was 44.2 (23-67) years. In total, nine (64.3%) patients had pubic symphysis disjunction, four (28.6%) had bilateral fractures of the obturator frames, and one (7%) had both. None of the patients required conversion to open surgery. The median operating times for symphysis pubis disruption, obturator frame fracture, and patients with both injuries were 90.0 (60-120), 135 (105-180), and 240 min, respectively. The median overall operating time was 102.5 (60-240) min. The median Iowa Pelvic Score and Majeed Functional Score at the last follow-up were 87 (70-99) and 84 (70-100), respectively. CONCLUSION: Laparoscopic internal fixation is a reliable treatment for pelvic ring disruption. The clinical and radiological outcomes of our patients suggest the usefulness of this technique as an alternative to open approaches.

Augmented versus non-augmented Trochanteric Fixation Nail-Advanced (TFNA) nails for treating trochanteric fractures in patients over sixty-five years of age.

PURPOSE: Intramedullary nailing is a common treatment for pertrochanteric fractures. However, implant-related mechanical failures, such as cut-out and cut-through, lead to higher rates of revision surgery, loss of autonomy, and mortality. Cemented augmentation enhances the bone-implant interface. This study compared the frequency of mechanical failures between augmented and non-augmented Trochanteric Fixation Nail-Advanced (TFNA) nails. METHODS: This descriptive, retrospective study at a level 1 trauma centre included patients aged > 65 years with pertrochanteric fractures treated by a short augmented or non-augmented TFNA nail. The primary outcome was the comparison of cut-out or cut-through rates between groups at three and six months postoperatively. RESULTS: Of the 181 patients analysed, 103 had augmented TFNA nails and 78 had non-augmented TFNA nails. There were no statistically significant differences between groups in terms of demographic characteristics, AO/OTA classification, or quality of reduction. The failure rate was significantly lower in the augmented group than in the non-augmented group: 1 (0.97%) versus 9 (11.54%) (p = 0.005). At six months postoperatively, there was no significant difference between the two groups concerning functional recovery, as measured by the Parker and EuroQoL 5-Dimensions scores. CONCLUSIONS: For patients aged over 65 years, the use of the augmented TFNA nail may reduce the risk of fixation failures such as cut-out.

Is a Total Hip Arthroplasty Stem in Varus a Risk Factor of Long-Term Mechanical Complication?

BACKGROUND: The impact of implanting cementless femoral stems in varus alignment on long-term mechanical complications remains poorly defined in the literature. The aim of our study was to compare survivorship and functional and radiographic outcomes of stems in varus alignment to those in neutral alignment with and average follow-up of 10 years. METHODS: This single-center, multisurgeon, retrospective case-control study compared a group of 105 total hip arthroplasty (THA) patients who had varus stem alignment (Varus Stem) to a matching group of 105 THA patients who had neutral stem alignment, operated on between January 2007 and December 2012. The primary outcome measure was implant survival. Secondary outcomes included functional (Harris Hip Score, Postel Merle d'Aubigné Score, thigh pain, dislocation and hip range of motion) and radiographic outcomes (radiolucency, osseointegration, heterotopic ossification, subsidence, and stress shielding). RESULTS: There was no significant difference in implant survival between the 2 groups with 95.7% (±2.46) in the Varus Stem group versus 97.7% (±1.64) in the Neutral Stem group (P = .41) after an average follow-up of 10 years. There was no significant difference in clinical and radiographic outcomes between groups. CONCLUSION: Cementless femoral stems in varus alignment were not the cause of mechanical complications with an average follow-up of 10 years. The comparison between groups in terms of implant survival, functional, and radiographic outcomes does not show any significant differences. Positioning a femoral stem in varus alignment may be an alternative for surgeons wishing to restore preoperative offset and to ensure satisfactory hip stability.

Epidemiology and characteristics of firearm injuries in a French level I trauma centre, 2009-2019.

BACKGROUND: Firearm injuries (FI) are an increasing problem in Europe but there have been few European epidemiological studies on civilian FI, particularly in France. This study investigated the epidemiology of FI at a French level I trauma centre. METHODS: A retrospective cohort study was conducted of all patients admitted to our centre with an FI between January 2009 and December 2019. We investigated the epidemiological trends of FI during the study period, and characterised the FI. RESULTS: A total of 162 patients were victims of FI. Prevalence was 0.11% and the mean annual incidence was 10.4 per 100 000 habs. A significant increase has been observed over the last 10 years, from 5 cases in 2009 (3.1%) to 30 in 2019 (18.5%). Of the 162 victims, 85 (52.5%) died as a direct result of the FI: 72 suicides (88.9%) and 9 victims of urban violence (11.1%) (armed public environment disorder). 95.3% of the patients died before reaching at the hospital. There were 95 cases (58.7%) of suicide and 33 cases (20.4%) of urban violence. The head was shot in 87 cases (48.9%), the thorax in 32 cases (18.5%) and the lower limbs in 24 cases (13.5%). A total of 106 surgeries were performed on 54 patients (33.3%). CONCLUSIONS: We identified 162 cases of FI with a mean annual incidence of 10.4 per 100 000 habs. A significant increase in FI was observed over the last 10 years. 52.2% of patients died, and the main context was suicide or attempted suicide.

Immediate full weight bearing after pelvic percutaneous fixation by screw for simple acetabular and pelvic ring fractures in patients older than sixty five years.

PURPOSE: The aim of this study was to assess the walking and weight-bearing abilities of patients older than 65 years with a simple acetabular or pelvic ring fracture treated with pelvic percutaneous screwing (PPS). METHODS: This study included 27 patients. This was a retrospective, single-centre observational study conducted in a level 1 trauma centre from September 2019 to April 2021. All patients older than 65 years who underwent PPS for an acetabular or pelvic ring fracture were included. RESULTS: All patients were able to walk and bear weight at one day after PPS. The mean walking distance increased from 19.4 m the day after the operation to 59.8 m, 497.8 m, and 1402 m at discharge, three and six weeks after the operation, respectively. The average pain visual analog scale scores before and after the operation were 4.1 (range, 3.6-5.1; standard deviation [SD], 0.63) and 0.9 (range, 0.5-1.2; SD, 0.25), respectively (p < .0001). The average daily dose of paracetamol used before and after the operation was 2.2 (range, 1.7-3.1; SD, 0.59) g/d and 1.3 (range, 0.6-1.7; SD, 0.40) g/d, respectively (p = .0232). The average daily dose of morphine used before and after the operation was 5.7 (range, 4.7-6.7; SD, 0.76) mg/d and 1.6 (range, 0.5-2.9; SD, 1.09) mg/d, respectively (p = .0001). CONCLUSION: All included patients were able to walk at one day after PPS. PPS was associated with reduced pain as well as a reduction in paracetamol and morphine use.

A Case-Control Comparison of Single-Stage Bilateral vs Unilateral Medial Unicompartmental Knee Arthroplasty.

BACKGROUND: We aimed to compare postoperative pain, functional recovery, and patient satisfaction among patients receiving one-stage medial bilateral or medial unilateral UKA (unicompartmental knee arthroplasty). Our main hypothesis was that during the first 72 postoperative hours, patients who underwent medial bilateral UKA did not consume more analgesics than those who underwent medial unilateral UKA. METHODS: A prospective case-control study was undertaken involving 148 patients (74 one-stage medial bilateral vs 74 medial unilateral Oxford UKA). The primary outcome was evaluation of the postoperative total consumption of analgesics from 0 to 72 hours. Next, the postoperative evolution of pain scores and functional recovery were assessed. Oxford Knee Scores were assessed preoperatively at 6 and 12 months with the occurrence of clinical or radiological complications. Finally, patient satisfaction was evaluated at the final follow-up. RESULTS: The cumulative sums of analgesic consumption (0-72 hours) calculated in the morphine equivalent dose were 21.61 ± 3.70 and 19.11 ± 3.12 mg in the patient and control groups, respectively (P = .30). Moreover, there were no significant differences in terms of pain scores (P = .45), functional recovery (P = .59, .34), length of stay (P = .18), Oxford Knee Scores (P = .68, .60), complications (P = .50), patient satisfaction (P = .66), or recommendations for intervention (P = .64). CONCLUSION: Patients who undergo one-stage medial bilateral UKA do not experience more pain and do not consume more analgesics than those who undergo medial unilateral UKA. A bilateral procedure is not associated with a lower recovery or a higher rate of complications, as functional outcomes at 6 and 12 months are similar to those of unilateral management.

The Radial Floating Cup radial head prosthesis to treat radial head fractures: functional and radiographic results after more than 12 years of mean follow-up.

INTRODUCTION: This study was performed to evaluate the long-term clinical and radiographic results of patients presenting with a radial head fracture who were treated surgically with a Judet Radial Floating Cup 2 (RFC 2) radial head prosthesis. MATERIALS AND METHODS: This was a retrospective, monocentric, observational, multi-operator, and continuous study performed between July 1997 and June 2009 on the treatment of radial head fracture using an RFC 2 radial head prosthesis. The primary efficacy endpoint was the functional status of the operated elbow, evaluated using the Disability of Arm-Shoulder-Hand (Quick-DASH) score and the Mayo Elbow Performance Index (MEPI). The secondary endpoints were mobility and stability of the operated elbow, residual pain and grip strength, nature and rate of complications, as well as possible radiographic abnormalities during follow-up. RESULTS: Twenty-two patients were treated with the RFC 2 for radial head fractures over the study period. Three (13.6%) were lost to follow-up, including one death. Of the remaining 19 patients, three RFCs had to be removed (15.8%). The final analysis involved 16 patients. The mean follow-up was 144 months (range 109-225 months; standard deviation [SD] = 49.9 months) or 12 years. The average Quick-DASH score was 23.01/100 (range 0-50; SD = 7.8) and three cases were rated as having "excellent" results according to the MEPI (18.7%), nine cases were rated as having "good" results in (56.2%), and four cases were rated as having "average" results (25%). The average mobility values were: 132° of flexion (range 120°-150°; SD = 11), 14.5° of extension deficit (range 0°-40°; SD = 5), 84.4° of pronation (range 20°-90°; SD = 8°), and 67.7° of supination (range 25°-85°; SD = 10). All patients had a stable elbow. The average grip strength on the affected side thus corresponded to 79% (range 44-100%; SD = 8.3%) of the grip strength on the healthy side. Four patients (25%) developed complications: three cases of algodystrophic syndrome (18.7%) and one case of early dislocation (6.2%). Radiographic evaluation revealed that there was a periprosthetic radio-lucencies in eight patients (50%), periarticular ossifications in 12 patients (75%), and lysis of the capitulum in two patients. There was no significant difference in MEPI ratings between patients with and without a periprosthetic radio-lucencies (P = 0.8018). CONCLUSIONS: Our results indicated that using the RFC 2 prosthesis to surgically treat radial head fractures provides good long-term functional results, including satisfactory mobility and stability.

Accuracy and Precision of an Ultrasound-Based Device to Measure the Pelvic Tilt in Several Positions.

OBJECTIVES: A new ultrasound-based device is proposed to measure the patient-specific pelvic tilt in different daily positions. The aim of this study was to assess the accuracy of this device as well as the intraobserver and interobserver precisions. METHODS: The accuracy was assessed by performing several tilt measurements with the device on a testing mechanical bench. The error was defined as the difference between the tilt measured with the device and the tilt provided by this test bench. Three physicians, a novice, an intermediate, and an expert user, were also asked to perform 10 measurements on 3 healthy volunteers with low, medium, and high body mass indices to analyze the intraobserver and interobserver precisions. These 10 measurements were performed in the standing, sitting, and supine positions. RESULTS: The mean accuracy of the device ± SD was 1.1° ± 0.7° (range, 0°-4.0°). The interobserver and intraobserver precisions were excellent whatever the body mass index and good to excellent according to the positions. There was no learning curve, and the time required to complete the measurements was approximately 5 minutes. CONCLUSIONS: This study presents an accurate and precise noninvasive device for measurement of the pelvic tilt in different positions.

The Lefèvre retentive cup compared with the dual mobility cup in total hip arthroplasty revision for dislocation.

BACKGROUND: Limiting the risk of dislocation is one of the main aims of both dual mobility and Lefèvre retentive cups. However, these devices have never been compared. The goal of our study was to compare these devices in total hip arthroplasty revisions for instability. The judgement criterion was non-recurrence of dislocation in a follow-up period of eight years. METHODS: This retrospective case-control study compared two continuous paired series of total hip arthroplasty revisions for instability. These series included 63 patients and 159 patients with implantation of a Lefèvre retentive cup and a dual mobility cup, respectively. RESULTS: The success rate at eight years (i.e., no recurrence) was 91 ± 0.05% and 95 ± 0.02% in the Lefèvre retentive cup and dual mobility groups, respectively. The difference was not statistically significant (p = 0.6). CONCLUSION: It seems that the Lefèvre retentive cup provides comparable outcomes with the dual mobility cup in the total hip arthroplasty revisions for instability, avoiding recurrence in long term.

Distal radius fracture osteosynthesis by volar locking plate: influence of epiphyseal screw positioning on risk of loss of reduction.

Ulnar variance is an important radiological parameter for good functional outcome after distal radius fracture osteosynthesis. Secondary loss of reduction due to radial shortening is a common complication after volar locking plate fixation. Some authors recommend beginning by placing the most ulnar epiphyseal screw, ensuring that it is positioned as close as possible to the distal radioulnar and radiocarpal joints. The hypothesis of our study was that the positioning of the ulnar epiphyseal screw relative to the distal radioulnar and radiocarpal joints influences the maintenance of reduction during follow-up. 190 distal radius fractures were treated with volar locking plate fixation and divided into two cohorts: cohort A with <2 mm and cohort B with ≥2 mm loss of ulnar variance. Minimum follow-up was 45 days. The positioning of the most ulnar epiphyseal screw was evaluated using a single variable, the ulno-distal index. Means were compared using t-tests and proportions using chi-squared tests. The alpha risk was set at 5%. The intra- and inter-observer reliability of the ulno-distal index measurement were assessed. Mean ulno-distal index was significantly lower in cohort A at 11.28 mm, compared to 13.33 mm in cohort B; p < 0.0001. Ulno-distal index <12 mm was a significant protective factor: p < 0.0001 and relative risk 0.558. No other intrinsic or extrinsic factors of secondary loss of reduction significantly influenced the risk of ulnar variance alteration. The study confirmed the hypothesis that, in distal radius fracture treated with volar locking plate fixation, the closer the ulnar epiphyseal screw to the distal radioulnar joint and radiocarpal joint, the lower the risk of ulnar variance alteration.

The "Metaizeau trick" to facilitate medullary pubic ramus screw insertion: A technical note.

Minimally invasive procedures have recently seen an increase in the treatment of pelvic ring disruptions and select acetabular fractures. Similar to ilio-sacral screws, the superior pubic ramus screw is becoming a preferred method for treating unstable pelvic ring fractures. While the osteology of the superior pubic ramus is well understood and has inherent variability, standard screw insertion techniques work effectively in most cases. If the anatomy prevents the standard approach, there are alternative methods that can be employed for successful screw placement, or there might be a need for an open reduction and internal fixation with plates. Such techniques can be material-intensive and time-consuming. In this paper, we introduce a straightforward method that utilizes the Metaizeau nail as a guide wire to facilitate screw insertion in most instances, termed the "Metaizeau trick". Metaizeau nails, commonly found in trauma centers, are designed to locate a pathway effortlessly using this method. LEVEL OF EVIDENCE: IV.

Consolidation rate in ulnar shortening osteotomy with the APTUS Wrist plate.

INTRODUCTION: Ulnocarpal impaction syndrome causes pain on the ulnar side of the wrist. Various surgical techniques have been described. Ulnar shortening osteotomy is now a standard treatment. However, it is associated with complications such as non-union of the osteotomy site. The main study objective was to report the rate of radiographic consolidation after ulnar shortening osteotomy with a cutting guide. MATERIAL AND METHODS: This multicenter retrospective study of 30 cases reported clinical and radiographic criteria at a minimum 6 month's follow-up. RESULTS: The non-union rate was 3.4%. One case presented non-union of the osteotomy site. 87% of patients were satisfied or very satisfied with the procedure. Mean VAS pain rating was 2.7 ± 2.4. Mean QuickDASH and PRWE scores were 24.7 ± 19.2 and 28.6 ± 25. Mean strength on Jamar dynamometer was 27.4 ± 8.9 kg. One patient developed complex regional pain syndrome. Five patients required plate removal for hardware-related discomfort. DISCUSSION: Ulna shortening osteotomy with the Aptus Wrist plate provides a standardized approach to the surgical treatment of ulnocarpal impaction syndrome. Compared with other series in the literature, the procedure provided satisfactory consolidation and clinical results.

Variations in pelvic tilt during day-to-day activities after total hip arthroplasty measured with an ultrasound system.

INTRODUCTION: The pelvis plays a major role in the orientation of total hip arthroplasty (THA) implants and consequently, on the postoperative stability of the new hip joint. The relationship between the spine and pelvis affects the functional orientation of the acetabular cup, although this relationship differs between individuals and the positions encountered in everyday life. We believe this should be factored in when planning the THA procedure. This led us to conduct an in vivo ultrasound study to document the values of pelvic tilt in standing, sitting and lying positions in patients who have advanced hip osteoarthritis, before and after they undergo THA. HYPOTHESIS: The pelvic tilt when standing, sitting and lying supine does not change significantly after THA. MATERIALS AND METHODS: The pelvic tilt, defined as the angle between the anterior pelvic plane and a vertical line was measured using an ultrasound device in 30 patients before the THA procedure and again 6 months later in standing, sitting and lying positions. The measurements were done during an office visit with the patient on an examination table for the lying position, on a chair for the sitting position and with the heels and occiput against the wall for the standing position. RESULTS: The preoperative and 6-month postoperative pelvic tilt were -5.6̊±10.4̊ [-30.6̊; 11.7̊] and -5.8̊±7.9̊ [-20.6̊; 10.4̊] (p=0.4129) when standing, -44.5̊±6.10 [-53.8̊; -23.9̊] and -43.5̊±6.9̊ [-54.4̊; -17.3̊] (p=0.5760) when sitting, -88.3̊±5.1̊ [-99.3̊; -78.7̊] and -87.9̊±5.9̊ [-97.6̊; -72.4̊] (p=0.6106) when lying supine, respectively. There was no significant difference in the pelvic tilt before and 6 months after THA procedure. Variations of±5̊; ±5-10̊; ±10-15̊ and 15-20̊ were found in 72% (18); 20% (5); 4% (1) and 4% (1) of patients when lying supine, 56% (14); 36% (9); 8% (2); 0% (0) of patients when standing and 76% (19); 24% (6); 0% (0); 0% (0) when sitting. The mean variation for each patient between the preoperative and 6 months postoperative measurement was 4.8±3.4̊ [0.8̊; 10.4̊] (p=0.4129), 3.5±2.3̊ [0.2̊; 9.1̊] (p=0.5760), and 4.6̊±3.2̊ [1.2̊; 15.4̊] (p=0.6106) for the standing, sitting and lying positions respectively. CONCLUSION: The pelvic tilt does not significantly change 6 months after THA. Taking into account the various positions used in everyday life may help to optimize the implant position. We have described the use of an affordable, accurate and non-irradiating device that provides fast and easy measurements of pelvic tilt in various positions. LEVEL OF EVIDENCE: IV.

Study of the position of six volar locking plates for distal radius fracture relative to the watershed line.

INTRODUCTION: Volar plate malpositioning in the treatment of distal radial fracture can lead to tendinitis or even tendon tear, especially when the plate position is very distal. We studied the impact of design on plate position in the distal radius. The primary aim was to compare the position of six volar wrist plates relative to the watershed line using the Soong classification. The secondary objectives were to assess the epidemiology of volar locking plate fixation within the administrative Département of Finistère (northwestern France) and to study whether the type of fracture played a role in plate position. HYPOTHESIS: The plate design itself influences positioning relative to the watershed line on the Soong classification. MATERIALS AND METHODS: A total of 2723 volar locking plate fixation cases were analyzed and categorized according to the Soong classification. Plates used were divided into six groups based on design: Zimmer Biomet®, Newclip Technics®, Stryker®, Synthes®, Medartis® and Medartis® Footprint. The number of Soong 0 + 1 plates (i.e., plates graded 0 and 1 taken together) was determined for each design, then compared using the Marascuilo procedure with a significance level of α = 0.05. RESULTS: On the Marascuilo procedure, we found significant differences in the number of Soong grade 0 + 1 plates. The Zimmer Biomet and Newclip Technics® plates were significantly more often proximal to the watershed line than the Synthes and Medartis Footprint plates. Plate position with the Medartis® design was significantly more proximal to the watershed line than for its companion design, the Medartis® Footprint plate. The rate of volar locking plate fixation of distal radial fractures over the past 10 years increased in Finistère. Also, the type of fracture affected the choice of plate when different designs were available within a hospital center (Medartis® Footprint plate used in 2R3A fractures). CONCLUSION: Our study highlights a significant difference in volar locking plate position relative to the watershed line between the various models available. Plate design is a deciding factor when treating distal radial fracture, to avoid impingement when implant removal is not routinely planned.

Post-traumatic total wrist arthrodesis: Satisfaction study of 42 cases at a mean 97months' follow-up.

INTRODUCTION: Total wrist arthrodesis is effective in reducing pain in osteoarthritic wrist, but at the cost of range of motion. The aim of the present study was to assess patient satisfaction after post-traumatic total wrist arthrodesis, complications and risk factors. HYPOTHESIS: Post-traumatic total wrist arthrodesis provides a high rate of satisfaction. PATIENTS AND METHODS: A single-center retrospective observational satisfaction survey was carried out for the period 2005-2020 by telephone interview. RESULTS: Forty-two post-traumatic dorsal plate total wrist arthrodeses were included. Mean follow-up was 97 months. Total arthrodesis achieved a mean 75% reduction in pain, with good functional results (QuickDASH: 23±9.1 [11-42]) and satisfaction (83% of patients very satisfied or satisfied). Seventy-two percent of patients continued in their previous work. The complications rate was 48%. Twenty patients had complications, including 14 (33%) requiring surgical revision. Thirteen patients (31%) had hardware removed due to plaque discomfort and 1 due to bone and joint infection. Seven patients showed CRPS. CONCLUSION: Total wrist arthrodesis provided good results in terms of pain relief and satisfaction, at the cost of loss of motion. It is a reliable surgical technique, with an essential place in the therapeutic algorithm for post-traumatic osteoarthritic wrist, particularly in manual workers. LEVEL OF EVIDENCE: IV, single-center retrospective observational study.

Functional safe zone for THA considering the patient-specific pelvic tilts: An ultrasound-based approach.

The usual Lewinnek orientation for cup positioning in total hip arthroplasty is not suitable for all patients as it does not consider the patient mobility. We propose an ultrasound-based approach to compute a Functional Safe Zone (FSZ) considering daily positions. Our goal was to validate it, and to evaluate how the input parameters impact the FSZ size and barycentre. The accuracy of the FSZ was first assessed by comparing the FSZ computed by the proposed approach and the true FSZ determined by 3D modelling. Then, the input parameters' impact on the FSZ was studied using a principal component analysis. The FSZ was estimated with errors below 0.5° for mean anteversion, mean inclination, and at edges. The pelvic tilts and the neck orientation were found correlated to the FSZ mean orientation, and the target ROM and the prosthesis dimensions to the FSZ size. Integrated into the clinical workflow, this non-ionising approach can be used to easily determine an optimal patient-specific cup orientation minimising the risks of dislocation.

Anterior pelvic plane estimation for total hip arthroplasty using a joint ultrasound and statistical shape model based approach.

Orienting properly the prosthetic cup in total hip arthroplasty is key to ensure the postoperative stability. Several navigation solutions have been developed to assist surgeons in orienting the cup regarding the anterior pelvic plane (APP), defined by both anterior superior iliac spines (ASIS) and the pubic symphysis. However acquiring the APP when the patient is ready for surgery, i.e., mainly in lateral decubitus, is difficult due to the contralateral ASIS being against the operating table. We propose a method to determine the APP from both (1) alternative anatomical landmarks which are easy to acquire with a navigated ultrasound probe and (2) a Statistical Shape Model (SSM) of the pelvis. After creating a pelvic SSM from 40 data, a SSM-based morphometric analysis has been carried out to identify the best anatomical landmarks allowing the easy determination of the APP. The proposed method has then been assessed with both in silico and in vivo experiments on respectively forty synthetic data, and five healthy volunteers. The in silico experiment shows the feasibility to determine the APP with an average error of 4.7∘ by only acquiring the iliac crest, the anterior superior iliac spine, the anterior inferior iliac spine, and the pubic symphysis. The average in vivo error using the ultrasound modality was 7.3∘ with an estimated impact on both the cup anteversion and inclination of 4.0∘ and 1.7∘ respectively. The proposed method shows promising results that could allow the determination of the APP in lateral decubitus with a clinically acceptable impact on the computation of the cup orientation.

WALANT for hand wound exploration in isolated conditions: Feasibility study.

INTRODUCTION: Military doctors usually deal with hand wound management. Their practice sometimes takes them far from any specialized surgical center. The WALANT could be a powerful tool for doctors operating in nuclear submarines or as part of special forces. This is a comparative, prospective and multicenter study. The hypothesis was that the management of hand wounds by military doctors specifically trained in WALANT and in the surgical exploration of hand wounds allowed a diagnosis as effective as in the FESUM center. PATIENTS AND METHODS: Military doctors, usually operating in isolated conditions, were trained at WALANT. Then, this method was used for the exploration of hand wounds in the emergency room, in a center outside FESUM. At the end, two different questionnaires were completed respectively by the patient and the operator. They aimed to assess various criteria such as the overall satisfaction of the patient and the operator, the level of pain felt or the ability of the operator to establish a precise lesion assessment. The results were compared with those obtained under the same conditions by hand surgeons in the FESUM centre. RESULTS: No significant difference was found between the two centers in terms of diagnostic capacity, satisfaction, comfort and perceived pain intensity. DISCUSSION: Under cover of prior training, the WALANT is effective for the exploration of hand wounds by submariner doctors and members of the special forces. Its use makes it possible to establish a precise injury report and this in material and human conditions approaching as closely as possible those of the armed forces on mission. The comfort of the patient remains preserved. CONCLUSION: The WALANT represents an effective tool for the exploration and lesion assessment of hand wounds outside the FESUM centre. Since emergency conditions are similar to those encountered in operational conditions, its use is also possible in situations specific to military doctors: nuclear submarines, special forces on mission. LEVEL OF EVIDENCE: III; comparative study, retrospective, multicentre.