Pseudotumoral calcinosis of the elbow with ulnar and radial nerve deficits.

We report here a rare case of an acute peripheral nerve compression by pseudotumoral calcinosis (PCT) at the right elbow in a patient with severe tertiary hyperaparathyroidism. This complication required urgent multidisciplinary management. Surgical decompression by PCT resection enabled rapid motor and sensory recovery.

Restoration of internal rotation after reverse shoulder arthroplasty may vary depending on etiology in patients younger than 60 ​years of age: a multicenter retrospective study.

BACKGROUND: Reverse shoulder arthroplasty (RSA) offers promising functional outcomes for young patients, yet challenges persist in restoring internal rotation (IR). This study aimed to assess the restoration of IR after RSA in patients younger than 60 years of age and analyze the factors affecting IR recovery. METHODS: A retrospective multicenter study was conducted, examining the functional outcome of patients who underwent RSA, with a minimum follow-up period of 2 years. Two subgroups of patients who underwent primary RSA were analyzed separately with respect to active internal rotation with the elbow at the side (AIR1): "difficult AIR1" and "easy AIR1." RESULTS: The study included 136 patients (overall series) with a mean age of 51.6 years. The overall series showed statistically significant improvement in active range of motion (RoM), pain, and Constant scores, especially with active IR (p â€‹< â€‹0.01). According to etiology, statistically significant improvement (p â€‹< â€‹0.05) in active IR was observed for fracture sequelae, primary osteoarthritis, and rheumatoid arthritis, whereas no statistically significant improvement in IR was observed for tumor, revision, and cuff-tear arthropathy (p â€‹> â€‹0.05). In subgroup analysis, patients with easy AIR1 displayed a statistically significant lower body mass index and better Constant score mobility, as well as improved motion in forward elevation and active IR (p â€‹< â€‹0.05). No statistically significant associations were found between improved IR and prosthetic design or subscapularis repair. Scapular notch, lysis of the graft, and teres minor atrophy were significantly associated with better active IR (p â€‹< â€‹0.05). CONCLUSION: RSA improves active RoM, pain, and functional outcomes in patients aged under 60. However, the degree of improvement in IR may vary depending on several factors and the underlying etiologies. These insights are crucial for patient selection and counseling, guiding RSA optimization efforts. LEVEL OF EVIDENCE: IV.

Total blood loss after hip hemiarthroplasty for femoral neck fracture: Anterior versus posterior approach.

INTRODUCTION: Femoral neck fractures constitute a public health problem due to significant associated morbidity and mortality amongst the ageing population. Perioperative blood loss can increase this morbidity. Blood loss, as well as the influence that the surgical approach exerts on it, remains poorly evaluated. We therefore conducted a retrospective comparative study in order to: (1) compare total blood loss depending on whether the patients were operated on using an anterior or posterior approach, (2) compare the transfusion rates, operating times and hospital stays between these two groups and, (3) analyze dislocation rates. HYPOTHESIS: Total blood loss is greater from an anterior approach following a hip hemiarthroplasty for femoral neck fracture, compared to the posterior approach. MATERIAL AND METHODS: This retrospective single-center comparative study included 137 patients operated on by hip hemiarthroplasty between December 2020 and June 2021, and seven patients were excluded. One hundred and thirty patients were analyzed: 69 (53.1%) had been operated on via the anterior Hueter approach (AA) and 61 (46.9%) via the posterior Moore approach (PA). The analysis of total blood loss was based on the OSTHEO formula to collect perioperative "hidden" blood loss. The risk of early dislocation (less than 6 months) was also analyzed. RESULTS: Total blood loss was similar between the two groups, AA: 1626±506mL versus PA: 1746±692mL (p=0.27). The transfusion rates were also similar between the two groups, AA: 23.2% versus PA: 31.1% (p=0.31) as well as the duration of hospitalization, AA: 8.5±3.2 versus PA: 8.2±3.3 days (p=0.54). The operating time was shorter in the PA group (Δ=10.3±14.1minutes [p<0.001]) with a greater risk of early dislocation when the patient was operated on by PA with AA: 9.8% versus PA: 1.4% (p=0.03). CONCLUSION: This study does not demonstrate any influence of the approach (anterior or posterior) on total blood loss. Transfusion rates and length of hospitalization were similar between the groups with a slightly shorter operating time but a greater risk of early dislocations after posterior hemiarthroplasty in a population at high anesthesia-related risk. LEVEL OF PROOF: III, comparative study of continuous series.

Is preoperative 3D planning reliable for predicting postoperative clinical differences in range of motion between two stem designs in reverse shoulder arthroplasty.

BACKGROUND: We aim to predict a clinical difference in the postoperative range of motion (RoM) between 2 reverse shoulder arthroplasty (RSA) stem designs (Inlay-155° and Onlay-145°) using preoperative planning software. We hypothesized that preoperative 3D planning could anticipate the differences in postoperative clinical RoM between 2 humeral stem designs and by keeping the same glenoid implant. METHODS: Thirty-seven patients (14 men and 23 women, 76 ± 7 years) underwent a BIO-RSA (bony increased offset-RSA) with the use of preoperative planning and an intraoperative 3-dimensional-printed patient-specific guide for glenoid component implantation between January 2014 and September 2019 with a minimum follow-up of 2 years. Two types of humeral implants were used: Inlay with a 155° inclination (Inlay-155°) and Onlay with a 145°inclination (Onlay-145°). Glenoid implants remained unchanged. The postoperative RSA angle (inclination of the area in which the glenoid component of the RSA is implanted) and the lateralization shoulder angle were measured to confirm the good positioning of the glenoid implant and the global lateralization on postoperative X-rays. A correlation between simulated and clinical RoM was studied. Simulated and last follow-up active forward flexion (AFE), abduction, and external rotation (ER) were compared between the 2 types of implants. RESULTS: No significant difference in RSA and lateralization shoulder angle was found between planned and postoperative radiological implants' position. Clinical RoM at the last follow-up was always significantly different from simulated preoperative RoM. A low-to-moderate but significant correlation existed for AFE, abduction, and ER (r = 0.45, r = 0.47, and r = 0.57, respectively; P < .01). AFE and abduction were systematically underestimated (126° ± 16° and 95° ± 13° simulated vs. 150° ± 24° and 114° ± 13° postoperatively; P < .001), whereas ER was systematically overestimated (50° ± 19° simulated vs. 36° ± 19° postoperatively; P < .001). Simulated abduction and ER highlighted a significant difference between Inlay-155° and Onlay-145° (12° ± 2°, P = .01, and 23° ± 3°, P < .001), and this was also retrieved clinically at the last follow-up (23° ± 2°, P = .02, and 22° ± 2°, P < .001). CONCLUSIONS: This study is the first to evaluate the clinical relevance of predicted RoM for RSA preoperative planning. Motion that involves the scapulothoracic joint (AFE and abduction) is underestimated, while ER is overestimated. However, preoperative planning provides clinically relevant RoM prediction with a significant correlation between both and brings reliable data when comparing 2 different types of humeral implants (Inlay-155° and Onlay-145°) for abduction and ER. Thus, RoM simulation is a valuable tool to optimize implant selection and choose RSA implants to reach the optimal RoM.

Total shoulder arthroplasty for primary glenohumeral osteoarthritis: does posterior humeral subluxation persist after correction of the glenoid version at 5 years minimum?

BACKGROUND: Primary glenohumeral osteoarthritis is associated with both excessive posterior humeral subluxation (PHS) and excessive glenoid retroversion in 40% of cases. These morphometric abnormalities are a particular issue because they may be responsible for a deterioration in long-term clinical and radiologic outcomes. The aim of this study was to perform a computed tomographic (CT) analysis of patients who underwent total shoulder arthroplasty (TSA) for primary osteoarthritis (OA) with B2-, B3-, or C-type glenoids in whom an attempt was made to correct for excessive glenoid retroversion and excessive posterior humeral subluxation intraoperatively. MATERIAL: We performed a retrospective, single-center study including 62 TSA patients with a preoperative PHS of the glenohumeral joint (31 men, 31 women, 70 ± 9 years) between January 2000 and January 2014. Glenoids were classified as B2 (32 cases), B3 (13 cases), or C (17 cases). Glenoid retroversion was corrected by anterior asymmetric reaming. Patients were reviewed for clinical and CT scan assessment with a mean follow-up of 8.3 years (minimum 5 years). At final follow-up, the CT images were reconstructed in the scapular plane. A PHS index >65% defined persistence. RESULTS: The revision-free rate was estimated at 93%. Correlation between PHS and retroversion was moderate preoperatively (ρ = 0.58) and strong at final follow-up (ρ = 0.73). Postoperative CT scans on average showed a surgical correction of PHS compared to preoperatively (79% vs. 65% respectively, P < .05) and retroversion (20° vs. 10° respectively, P < .05). At final follow-up, 25 of 62 patients had a persistence in the 2-dimensional (2D) model and 41 of 62 in the corrected 2D model. Persistence of PHS had no influence on clinical outcomes but did demonstrate a significantly higher glenoid loosening rate (20% vs. 59%, P < .05). CONCLUSION: Correlation between PHS and retroversion was moderate preoperatively and strengthened at long-term follow-up. Anterior asymmetric reaming allowed for a surgical improvement of both PHS and retroversion, but it was not sufficient to maintain a correction over time. Glenoid loosening was more frequent in case of PHS persistence but seemingly without clinical relevance.

Are glenoid retroversion, humeral subluxation, and Walch classification associated with a muscle imbalance?

BACKGROUND: The etiology of humeral posterior subluxation remains unknown, and it has been hypothesized that horizontal muscle imbalance could cause this condition. The objective of this study was to compare the ratio of anterior-to-posterior rotator cuff and deltoid muscle volume as a function of humeral subluxation and glenoid morphology when analyzed as a continuous variable in arthritic shoulders. METHODS: In total, 333 computed tomography scans of shoulders (273 arthritic shoulders and 60 healthy controls) were included in this study and were segmented automatically. For each muscle, the volume of muscle fibers without intramuscular fat was measured. The ratio between the volume of the subscapularis and the volume of the infraspinatus plus teres minor (AP ratio) and the ratio between the anterior and posterior deltoids (APdeltoid) were calculated. Statistical analyses were performed to determine whether a correlation could be found between these ratios and glenoid version, humeral subluxation, and/or glenoid type per the Walch classification. RESULTS: Within the arthritic cohort, no statistically significant difference in the AP ratio was found between type A glenoids (1.09 ± 0.22) and type B glenoids (1.03 ± 0.16, P = .09), type D glenoids (1.12 ± 0.27, P = .77), or type C glenoids (1.10 ± 0.19, P > .999). No correlation was found between the AP ratio and glenoid version (ρ = -0.0360, P = .55) or humeral subluxation (ρ = 0.076, P = .21). The APdeltoid ratio of type A glenoids (0.48 ± 0.15) was significantly greater than that of type B glenoids (0.35 ± 0.16, P < .01) and type C glenoids (0.21 ± 0.10, P < .01) but was not significantly different from that of type D glenoids (0.64 ± 0.34, P > .999). When evaluating both healthy control and arthritic shoulders, moderate correlations were found between the APdeltoid ratio and both glenoid version (ρ = 0.55, P < .01) and humeral subluxation (ρ = -0.61, P < .01). CONCLUSION: This in vitro study supports the use of software for fully automated 3-dimensional reconstruction of the 4 rotator cuff muscles and the deltoid. Compared with previous 2-dimensional computed tomography scan studies, our study did not find any correlation between the anteroposterior muscle volume ratio and glenoid parameters in arthritic shoulders. However, once deformity occurred, the observed APdeltoid ratio was lower with type B and C glenoids. These findings suggest that rotator cuff muscle imbalance may not be the precipitating etiology for the posterior humeral subluxation and secondary posterior glenoid erosion characteristic of Walch type B glenoids.

Acute compartment syndrome of the lower limbs: Fasciotomy or dermofasciotomy? A cadaver study of compartment pressures.

BACKGROUND: Acute compartment syndrome (ACS) of the lower limbs is a function-threatening event usually managed by extended dermofasciotomy. Closure of the skin may be delayed, creating a risk of complications when there is an underlying fracture. Early treatment at the pre-ACS stage might allow isolated fasciotomy with no skin incision. The primary objective of this study was to compare intracompartmental pressure (ICP) changes after fasciotomy and after dermofasciotomy. The secondary objectives were to evaluate potential associations linking the starting ICP to achievement of an ICP below the physiological cut-off of 10mm Hg and to determine whether the ICP changes after fasciotomy and dermofasciotomy varied across muscle compartments. HYPOTHESIS: Fasciotomy with no skin incision may not provide a sufficient ICP decrease, depending on the initial ICP value. MATERIAL AND METHODS: A previously validated model of cadaver ACS of the lower limbs was used. Saline was injected gradually to raise the ICP to>15mmHg (ICP15), >30mmHg (ICP30), and >50mmHg (ICP50). We studied 70 leg compartments (anterior, lateral, and superficial posterior) in 13 cadavers (mean age, 89.1±4.6years). ICP was monitored continuously. Percutaneous, minimally invasive fasciotomy consisting in one to three 1-cm incisions was performed in each compartment. ICP was measured before and after fasciotomy then after subsequent skin incision. The objective was to decrease the ICP below 10mmHg after fasciotomy or dermofasciotomy. RESULTS: Overall, mean ICP was 37.8±19.1mmHg after the injection of 184.0±133.01mL of saline. In the ICP15 group, the mean ICP of 16.1mmHg fell to 1.4mmHg after fasciotomy (ΔF=14.7) and 0.3mmHg after dermofasciotomy (ΔDF=1.1). Corresponding values in the ICP30 group were 33.9mmHg, 4.7mmHg (ΔF=29.2), and 1.2mmHg (ΔDF=3.5); and in the ICP50 group, 63.7mmHg, 17.0mmHg (ΔF=46.7), and 1.2mmHg (ΔDF=15.8). Thus, in the group with initial pressures >50mmHg, the ICP decrease was greater after both procedures, but fasciotomy alone nonetheless failed to achieve physiological values (<10mmHg). The pressure changes were not significantly associated with the compartment involved (anterior, lateral, or superficial posterior) (p<0.05). CONCLUSION: Under the conditions of this study, higher baseline ICPs were associated with larger ICP drops after fasciotomy and dermofasciotomy. Nevertheless, when the baseline ICP exceeded 50mmHg, fasciotomy alone failed to decrease the ICP below 10mmHg. Adding a skin incision achieved this goal. LEVEL OF EVIDENCE: IV, experimental study.

An Evaluation of the Reliability of Manual Landmark Identification on 3D Segmented Wrists.

BACKGROUND: Three-dimensional (3D) preoperative planning is increasingly used in orthopaedic surgery. Two-dimensional (2D) characterization of distal radial deformities remains inaccurate, and 3D planning requires a reliable reference frame at the wrist. We aim to evaluate the reliability of the determination of anatomical points placed manually on 3D models of the radius to determine which of those points allow reliable morphometric measurements. METHODS: Twenty-three radial scans were reconstructed in 3D. Five operators specialized in the upper limb manually positioned 8 anatomical points on each model. One of the operators repeated the operation 6 times. The anatomical points were based on previously published 3D models used for radial inclination and dorsopalmar tilt measurements. The repeatability and reproducibility of the measurements derived using this manual landmarking were calculated using different measurement methods based on the identified points. An error of ≤2° was considered clinically acceptable. RESULTS: This study of intraobserver and interobserver variability of the anatomic points allowed us to determine the least variable and most accurately defined points. The middle of the ulnar border of the radius, the radial styloid, and the midpoint of the ulnar incisura of the radius were the least variable. The palmar and dorsal ends of the ridge delineating the scaphoid and lunate facets were the most variable. Only 1 of the radial inclination measurement methods was clinically acceptable; the others had a repeatability and reproducibility limit of >2°, making those measurements clinically unacceptable. CONCLUSIONS: The use of isolated points seems insufficient for the development of a wrist reference frame, especially for the purpose of measuring dorsopalmar tilt. If one concurs that an error of 2° is unacceptable for all distal radial measurements, then clinicians should avoid using 3D landmarked points, due to their unreliability, except for radial inclination measured using the radial styloid and the midpoint of the ulnar edge of the radius. A characterization of the wrist using 3D shapes that fit the articular surface of the radius should be considered. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Early morbidity and mortality after one-stage bilateral shoulder arthroplasty.

PURPOSE: One-stage bilateral shoulder arthroplasty has the advantage of requiring a single hospital stay and a single anaesthesia. The topic has been little reported, unlike one stage bilateral hip and knee arthroplasty, which have demonstrated their interest. The aim of the present study was to determine peri- and early post-operative morbidity and mortality after this procedure. The study hypothesis was that peri- and early post-operative morbidity and mortality in one stage bilateral shoulder arthroplasty is low in selected patients and that satisfaction is high. METHODS: A single-centre retrospective study assessed peri- and early post-operative morbidity and mortality in one stage bilateral shoulder arthroplasty. Twenty-one patients, aged < 80 years, with ASA score ≤ 3, were consecutively operated on between 1999 and 2020. Indications comprised primary osteoarthritis, aseptic osteonecrosis, inflammatory arthritis, massive rotator cuff tear, and dislocation fracture, involving both shoulders. RESULTS: There were no early deaths. The complication rate was 10% (4/21 cases). No prosthesis dislocation or sepsis was reported. Mean blood loss was 145 ± 40 cc, mean surgery time 164 ± 63 min, and mean hospital stay five ± four days. Only one patient required postoperative transfusion. Functional results at six months showed significantly improved range of motion and good patient satisfaction. CONCLUSIONS: One-stage bilateral shoulder arthroplasty was feasible in selected patients. Mortality was zero, and morbidity was low. Surgery time was reasonable and required no repositioning. Postoperative home help is indispensable for patient satisfaction during rehabilitation.

Are glenoid retroversion, humeral subluxation and Walch classification associated with a muscle imbalance.

INTRODUCTION: The etiology of humeral posterior subluxation remains unknown, and it has been hypothesized that horizontal muscle imbalance could cause this condition. The objective of this study was to compare the ratio of anterior to posterior rotator cuff muscle and deltoid volumes as a function of humeral subluxation and glenoid morphology when analyzed as continuous variable in arthritic shoulders. METHODS: Three hundred and thirty-three (273 arthritic and 60 healthy controls) CT scans of shoulders were included in this study and were segmented automatically. For each muscle, the volume of muscle fibers without intra-muscular fat was then measured. The ratio between the volume of the subscapularis and the volume of the infraspinatus + teres minor (AP ratio) and the ratio between the anterior and posterior deltoid (APdeltoid) were calculated. Statistical analyses were performed to determine whether a correlation could be found between these ratios and glenoid version/ humeral subluxation/glenoid type in the Walch classification. RESULTS: Within the arthritic cohort, no statistically significant difference was found between the AP ratio between A and type B glenoids (1.09 ± 0.22 versus 1.03 ± 0.16 p=0.09), between A and D type glenoids (1.09 ± 0.22 versus 1.12 ± 0.27, p=0.77) nor between the A and C type glenoids (1.09 ± 0.22 versus 1.10 ± 0.19, p=1). No correlation was found between AP ratio and glenoid version/humeral subluxation (rho =-0.0360, p=0.55; rho = 0.076; p=0.21). The APdeltoid ratio of type A glenoids was significantly greater than that of type B glenoids (0.48 ± 0.15 versus 0.35 ± 0.16, p< 0.01), and type C glenoids (0.48 ± 0.15 versus 0.21±0.10, p < 0.01) but not significantly different from the APdeltoid ratio of type D glenoids (0.48 ± 0.15 versus 0.64 ± 0.34, p=1). When evaluating both healthy control and arthritic shoulders, moderate correlations were found between APdeltoid ratio and glenoid version/humeral subluxation (rho=0.55, p<0.01; rho=-0.61, p<0.01). CONCLUSION: As opposed to previous two-dimensional CT scan studies, we did not find any correlation between AP muscle volume ratio and glenoid parameters in arthritic shoulders. Therefore, rotator cuff muscle imbalance does not seem to be associated with posterior humeral subluxation leading to posterior glenoid erosion and subsequent retroversion characteristic of Walch B glenoids. However, our results could suggest that a larger posterior deltoid pulls the humerus posteriorly into posterior subluxation, but this requires further evaluation as the deltoid follows the humerus possibly leading to secondary asymmetry between the anterior and the posterior deltoid.

IODA-shoulder®, a 3-dimensional automated software for glenoid bone loss quantification in shoulder instability. A validation study.

BACKGROUND: Glenoid bone loss (GBL) calculation in patients with shoulder instability has a wide variability in methods and their reliability. The purpose of this study was to describe and validate a new semi-automated software developed to improve GBL calculation using a 3D imaging modeling (IODA-shoulder) and to compare the method to the PICO area method. PATIENTS AND METHODS: A semi-automated software to assess GBL was preliminarily developed and validated on 7 fresh frozen specimens (scapulae with artificially created glenoid defect), using water displacement method. Afterwards, the software was retrospectively used on CT images of 20 patients affected by recurrent shoulder dislocation. Inclusion criteria were: unilateral dislocation, minimum 2 dislocation episodes. Exclusion criteria were bone reconstruction of the glenoid, failed shoulder stabilization, bilateral dislocation, shoulder arthritis. Three-dimensional computed tomography images of bilateral shoulder were retrieved for each patient. Two methods to determine GBL were compared. The PICO surface area method and the new IODA method. We assessed the intra- and inter-rater reliability of the two methods with the Intraclass Correlation Coefficient (ICC), the Bland-Alman analysis, and Lin's concordance correlation coefficient (CCC). RESULTS: We did not find a statistically significant difference between the mean volumes calculated with PICO and IODA methods, respectively 914 vs. 815 mm3, p=0.155. The analysis carried out by using the traditional PICO method showed a lower concordance rate among four observers than the higher concordance found using IODA method, regardless of the size and the location of the defect. The ICC agreement with PICO was significantly lower than with IODA (0.76 vs. 0.97). We found a poor CCC with PICO (from 0.65 to 0.81) and a substantial one with IODA (from 0.96 to 0.98). DISCUSSION: The intra- and inter-rater reliability using IODA method is significantly better than PICO method. The assessment of GBL using IODA method is time saving, avoiding significant inter- and intra-observer variation, mainly due to individual skill and experience in the method. LEVEL OF EVIDENCE: IV, experimental study.

Three-Dimensional Measurement of Proximal Humerus Fractures Displacement: A Computerized Analysis.

Neer's classification for proximal humerus fractures (PHFs) uses 10 mm and 45° thresholds to distinguish displaced fragments. While this system was originally developed referencing 2D X-rays, fracture displacements occur in three dimensions. Our work aimed to develop a standardized and reliable computerized method for measuring PHF 3D spatial displacements. CT scans of 77 PHFs were analyzed. A statistical shape model (SSM) was used to generate the pre-fracture humerus. This predicted proximal humerus was then used as a "layer" to manually reduce fragments to their native positions and quantify translation and rotation in three dimensions. 3D computerized measurements could be calculated for 96% of fractures and revealed that 47% of PHFs were displaced according to Neer's criteria. Valgus and varus head rotations in the coronal plane were present in 39% and 45% of cases; these were greater than 45° in 8% of cases and were always associated with axial and sagittal rotations. When compared to 3D measurements, 2D methods underestimated the displacement of tuberosity fragments and did not accurately assess rotational displacements. The use of 3D measurements of fracture displacement is feasible with a computerized method and may help further refine PHF analysis and surgical planning.

The Real Post-Operative Range of Motion Differs from the Virtual Pre-Operative Planned Range of Motion in Reverse Shoulder Arthroplasty.

INTRODUCTION: The purpose of this study was to analyze the real range of motion (RoM) measured in patients operated on for reverse shoulder arthroplasty (RSA) and compare it to the virtual RoM provided by the preoperative planning software. HYPOTHESIS: There was a difference between virtual and real RoM, which can be explained by different factors, specifically the scapula-thoracic (ST) joint. METHODS: Twenty patients with RSA were assessed at a minimum follow-up of 18 months. Passive RoM in forward elevation abduction, without and with manually locking the ST joint, and in external rotation with arm at side were recorded. The humerus, scapula, and implants were manually segmented on post-operative CTs. Post-operative bony structures were registered to preoperative bony elements. From this registration, a post-operative plan corresponding to the real post-operative implant positioning was generated and the corresponding virtual RoM analysis was recorded. On the post-operative anteroposterior X-rays and 2D-CT coronal planning view, the glenoid horizontal line angle (GH), the metaphyseal horizontal line angle (MH), and the gleno-metaphyseal angle (GMA) were measured to assess the extrinsic glenoid inclination, as well as the relative position of the humeral and glenoid components. RESULTS: There were some significant differences between virtual and post-operative passive abduction and forward elevation, with (55° and 50°, p < 0.0001) or without ST joint participation (15° and 27°, p < 0.002). For external rotation with arm at side, there was no significant difference between planning (24° ± 26°) and post-operative clinical observation (19° ± 12°) (p = 0.38). For the angle measurements, the GMA was significantly higher (42.8° ± 15.2° vs. 29.1°± 18.2°, p < 0.0001), and the GH angle, significantly lower on the virtual planning (85.2° ± 8.8° vs. 99.5° ± 12.5°, p < 0.0001), while the MH was not different (p = 0.33). CONCLUSIONS: The virtual RoM given by the planning software used in this study differs from the real post-operative passive RoM, except for external rotation. This can be explained by the lack of ST joint and soft tissues simulation. However, in focusing on the virtual GH participation, the simulation looks informative. Some modifications between the glenoid and humerus starting positions before running the motion analysis could be provided for making it more realistic and predictive of the RSA functional results. LEVEL OF EVIDENCE: III.

Glomus tumor of the scapular neck with axillary nerve compression at the shoulder. A case report.

Background: Glomus tumors, also known as benign acral tumors are extremely rare. Previous glomus tumors from other regions of the body have been linked to neurological compression symptoms, however axillary compression at the scapular neck has never been described. Case presentation: Here, we report a case of axillary nerve compression in a 47-year-old man, secondary to a glomus tumor of the neck of the right scapula, initially misdiagnosed with biceps tenodesis performed and no pain improvement. The magnetic resonance imaging demonstrated a well-contoured, 12 mm tumefaction at the inferior pole of the scapular neck T2-hyperintense and T1-isointense and interpreted as a neuroma. An axillary approach allowed the dissection of the axillary nerve, and the tumor was completely removed. The pathological anatomical analysis resulted in a nodular red lesion measuring 14 × 10 mm, delimited and encapsulated with a definitive diagnostic of glomus tumor. The neurologic symptoms and pain disappeared 3 weeks after surgery and the patient reported satisfaction with the surgical procedure. After 3 months, the results remain stable with a complete resolution of the symptoms. Conclusions: In cases of unexplained and atypical pain in the axillary area, and to avoid potential misdiagnoses and inappropriate treatments, an in-depth exploration for a compressive tumor should be performed as a differential diagnosis.

Validation of the shoulder range of motion software for measurement of shoulder ranges of motion in consultation: coupling a red/green/blue-depth video camera to artificial intelligence.

PURPOSE: Clinical evaluation of the shoulder range of motion (RoM) may vary significantly depending on the surgeon. We aim to validate an automatic shoulder RoM measurement system associating image acquisition by an RGB-D (red/green/blue-depth) video camera to an artificial intelligence (AI) algorithm. METHODS: Thirty healthy volunteers were included. A 3D RGB-D sensor that simultaneously generated a colour image and a depth map was used. Then, an open-access convolutional neural network algorithm that was programmed for shoulder recognition provided a 3D motion measure. Each volunteer adopted a randomized position successively. For each position, two observers made a visual (EyeREF) and goniometric measurement (GonioREF), blind to the automated software which was implemented by an orthopaedic surgeon. We evaluated the inter-tester intra-class correlation (ICC) between observers and the concordance correlation coefficient (CCC) between the three methods. RESULTS: For manual evaluations EyeREF and GonioREF, ICC remained constantly excellent for the widest motions in the vertical plane (i.e., abduction and flexion). It was very good for ER1 and IR2 and fairly good for adduction, extension, and ER2. Differences between the measurements' means of EyeREF and shoulder RoM was significant for all motions. Compared to GonioREF, shoulder RoM provided similar results for abduction, adduction, and flexion and EyeREF provided similar results for adduction, ER1, and ER2. The three methods showed an overall good to excellent CCC. The mean bias between the three methods remained under 10° and clinically acceptable. CONCLUSION: RGB-D/AI combination is reliable in measuring shoulder RoM in consultation, compared to classic goniometry and visual observation.

Anatomical plane and transverse axis of the scapula: Reliability of manual positioning of the anatomical landmarks.

Background: The aim of our study was to evaluate the accuracy of manual determination of the three key points defining the anatomical plane of the scapula, which conditions the reliability of planning software programs based on manual method. Method: We included 82 scapula computed tomography scans (56 pathologic and 26 normal glenoid), excluding truncation and major three-dimensional artifact. Four observers independently picked the three key points for each case. Inter- and intra-observer agreement was calculated for each point, using the intraclass correlation method. The mean error (mm) between the observers was calculated as the diameter of the smallest sphere including the four chosen positions. Results: Lower inter-observer agreement was found for the trigonum superoinferior position and for the glenoid center anteroposterior position. The mean positioning error between the four observers was 6.9 mm for the trigonum point, and error greater than 10 mm was recorded in 25% of the cases. The mean positioning error was 3.5 mm for the glenoid center in altered glenoid, compared to 1.8 mm for normal glenoid. Discussion: Manual determination of an anatomical plane of the scapula suffers from inaccuracy especially due to the variability in trigonum picking, and in a lesser extent, to the variability of glenoid center picking in altered glenoid.

Glenoid Inclination: Choosing the Transverse Axis Is Critical-A 3D Automated versus Manually Measured Study.

The aim of this study was to evaluate the variation in measured glenoid inclination measurements between each of the most used methods for measuring the scapular transverse axis with computed tomography (CT) scans, and to investigate the underlying causes that explain the differences. METHODS: The glenoid center, trigonum and supraspinatus fossa were identified manually by four expert shoulder surgeons on 82 scapulae CT-scans. The transverse axis was generated either from the identified landmarks (Glenoid-Trigonum line (GT-line), Best-Fit Line Fossa (BFLF)) or by an automatic software (Y-axis). An assessment of the interobserver reliability was performed. We compared the measured glenoid inclination when modifying the transverse axis to assess its impact. RESULTS: Glenoid inclination remained stable between 6.3 and 8.5°. The variations occurred significantly when changing the method that determined the transverse axis with a mean biase from -1.7 (BFLF vs. Y-axis) to 0.6 (BFLF vs. GT-line). The Y-axis method showed higher stability to the inclination variation (p = 0.030). 9% of cases presented more than 5° of discrepancies between the methods. The manual methods presented a lower ICC (BFLF = 0.96, GT-line = 0.87) with the widest dispersion. CONCLUSION: Methods that determine the scapular transverse axis could have a critical impact on the measurement of the glenoid inclination. Despite an overall good concordance, around 10% of cases may provide high discrepancies (≥5°) between the methods with a possible impact on surgeon clinical choice. Trigonum should be used with caution as its anatomy is highly variable and more than two single points provide a better interrater concordance. The Y-axis is the most stable referential for the glenoid inclination.

Can surgeons optimize range of motion and reduce scapulohumeral impingements in reverse shoulder arthroplasty? A computational study.

Background: Early glenohumeral impingement leads to poor range of motion and notching in reverse shoulder arthroplasty. The aim was to find from planning software which implant configuration provides the best motions in reverse shoulder arthroplasty. Patients and Methods: Reverse shoulder arthroplasty planning (Glenosys) was made in 31 patients (12 men, 19 women, 76 ± 6 yo) and impingements were analyzed. Inlay (155°-inclined) and Onlay (145°-inclined) humeral designs were tested. Four configurations were tested for each shoulder: "INLAY": non-lateralized glenoid-inlay humerus, "BIO-INLAY": lateralized glenoid (BIO-RSA)-inlay humerus, "ONLAY": non-lateralized glenoid-onlay humerus, and "BIO-ONLAY": lateralized (BIO-RSA) glenoid-onlay humerus. Results: BIO-ONLAY and BIO-INLAY groups presented a significantly better result in all tested motion (p < 0.001 for all tests). BIO-ONLAY allowed a significantly better external rotation, extension and adduction than BIO-INLAY with decreased impingements with the pilar. BIO-INLAY presented a significantly better abduction. In abduction, an abutment of the greater tuberosity against the acromion was associated with a lower range of motion (p < 0.0001) and did not depend on the lateralization. Conclusion: Glenoid lateralization delays the glenohumeral impingement in reverse shoulder arthroplasty and gives the best rotations, adduction and extension when associated with neutral inclination and humeral 145° inclination. Greater tuberosity abutment has to be avoided in abduction and the Inlay design provides the best abduction.

Congenital pseudarthrosis of the clavicle: a systematic review.

PURPOSE: There is no consensus on the type of surgical treatment of congenital pseudarthrosis of the clavicle due to its rarity. The purpose of this study is to provide evidence in favor of a surgical technique and to explore factors correlated with bone consolidation. METHODS: Systematic review of the literature and an analysis of the data for each subject, including all available subjects from the published series and clinical cases since 1990. Fisher's exact tests or T-tests were used to evaluate the effect of independent variables (age at surgery and type of treatment) on bone healing. RESULTS: The literature search provides 305 articles; 30 were selected, reporting 191 patients and 194 clavicles. One hundred and fifty-one clavicles were operated on at a mean age of nine years and four months (from 8 months to 21 years). Thirteen clavicles (8, 6%) had not consolidated at the last follow-up. Concerning the type of fixation, the rate of healing was similar for plates and pins (p = 0.27). The rate of consolidation was higher with autograft than with allograft, xenograft, or no graft (p = 0.00001), and was 100% for vascularized graft. The mean age at surgery was higher for patients who healed at the last follow-up (118 vs. 61 months, p = 0.001). CONCLUSION: In the event of surgical indication for congenital pseudarthrosis of the clavicle, it is recommended to perform autograft and stable fixation (level 4) after seven years old (level 4).