Is malunion of the greater tuberosity after reverse shoulder arthroplasty in patients with complex proximal humerus fracture associated with worse clinical outcomes? A prospective cohort study.

PURPOSE: To assess patient outcomes following reverse shoulder arthroplasty in patients with complex proximal humerus fracture and the clinical implications of greater tuberosity malunions. METHODS: This prospective study included 56 patients who underwent RSA (DELTA XTEND™, DePuy Synthes, Warsaw, IN, USA) to treat proximal humerus fractures. We used a standardized suture technique to reattach the tuberosities. Demographic, comorbidity, and radiological parameters were collected. Assessments at 2-year follow-up (n = 49) are given as follows: range of motion (ROM), pain level, Constant Murley scores (CS), subjective shoulder value (SSV), and tuberosity healing. RESULTS: Anatomic tuberosity healing was achieved in 31 (55%) patients (group 1), 14 (25%) had a malunion (group 2), and complete migration occurred in 11 (20%) (group 3). No statistically significant differences between groups 1 and 2 were detected: CS (p = 0.53), SSV (p = 0.07), ROM (forward flexion (FF) p = 0.19, internal rotation (IR) p = 0.34, and external rotation (ER) p = 0.76). Group 3 had poorer outcomes (median [IQR]) than group 1: CS (59 [50-71]) vs. 72 [65-78]), FF (120 [100-150]) vs. 150 [125-160] and ER (- 20 [- 20 to 10] vs. 30 [20-45], respectively. Three complications (group 1) occurred: one-stage revision after low-grade infection, haematoma due to early rivaroxaban intake, and open reduction and internal fixation for acromion insufficiency fracture. No patients showed signs of stem or glenoid loosening after 2 years. CONCLUSION: Cases with complete superior migration experienced poorer clinical outcomes than those with anatomic healing. Despite a relatively high malunion rate, the outcomes were not significantly worse in these patients compared to anatomically healed GT cases.

Augmented reality guided osteotomy in hallux Valgus correction.

BACKGROUND: An optimal osteotomy angle avoids shortening of the first metatarsal bone after hallux valgus surgery and therefore reduces the risk of transfer-metatarsalgia. The purpose of the present ex-vivo study was to investigate whether augmented reality (AR) would improve accuracy of the distal osteotomy during hallux valgus surgery. METHODS: Distal osteotomies of the first metatarsals were performed on a foot model by two surgeons with different levels of surgical experience each with (AR, n = 15 × 2) or without (controls, n = 15 × 2) overlay of a hologram depicting an angle of osteotomy perpendicular to the second metatarsal. Subsequently, the deviation of the osteotomy angle in the transverse plane was analyzed. RESULTS: Overall, AR decreased the extent of deviation and the AR guided osteotomies were more accurate (4.9 ± 4.2°) compared to the freehand cuts (6.7 ± 6.1°) by tendency (p = 0.2). However, while the inexperienced surgeon performed more accurate osteotomies with AR with a mean angle of 6.4 ± 3.5° compared to freehand 10.5 ± 5.5° (p = 0.02), no significant difference was noticed for the experienced surgeon with an osteotomy angle of around 3° in both cases. CONCLUSION: This pilot-study suggests that AR guided osteotomies can potentially improve accuracy during hallux valgus correction, particularly for less experienced surgeons.

Tuberosity union in patients with proximal humerus fractures treated with reverse shoulder arthroplasty: a technical note and exploratory analysis.

PURPOSE: The use of reverse shoulder arthroplasty (RSA) to treat complex humerus fractures is increasing, especially in older, osteoporotic patients. Refixation and tuberosity healing are needed to achieve an optimal range of motion (ROM), external rotation, active forward elevation, and patient satisfaction. Proper healing has been reported, however, in only 40-84% of cases. Our study's aim was to describe a simple, reproducible fixation technique designed to improve tuberosity healing. METHODS: We included 30 patients with acute proximal humerus fractures undergoing RSA (Global Unite Reverse Fracture, DePuy Synthes, Warsaw, IN, USA) with tuberosity reattachment. The humerus stem was cemented in 24 cases. A standardized suture technique with two fiber tapes was used to reattach tuberosities. Clinical and radiological parameters, which were collected one year post-operatively, included ROM, pain level, Constant scores, subjective shoulder value (SSV), and tuberosity healing. RESULTS: The mean age of the patients was 79.3 years (± 7; range 65-92), and the tuberosity healing rate was 90.0% (27 of 30). Two patients showed migration (one nonunion, one malunion), and another had complete resorption after an initial period of proper healing. Radiolucent lines around the humerus stem occurred in one case, and three patients had scapular notching. The mean SSV was 86% (± 11; range 60-100), the Constant score was 72 (± 10.3; range 48-92), the active forward flexion was 140° (± 14.3; range 115-165), and external rotation was 23° (± 16.5; range 0-50). CONCLUSIONS: This reattachment technique, which is simple and reproducible, achieved a higher tuberosity healing rate than previously published rates.

Prognostic value of N-terminal pro-B-type natriuretic peptide in patients with acute coronary syndromes undergoing left main percutaneous coronary intervention.

BACKGROUND: Patients undergoing acute left main (LM) coronary artery revascularization have a high mortality and natriuretic peptides such as N-terminal pro-B-type (NT-proBNP) have been shown to have prognostic value in patients with acute coronary syndromes. The present study looked at the prognostic value of NT-proBNP in these patients. METHODS AND RESULTS: We studied all consecutive patients undergoing acute LM coronary artery percutaneous coronary intervention between January 2005 and December 2008 in whom NT-proBNP was measured (n=71). We analyzed the clinical characteristics and the short- and long-term outcomes in relation to NT-proBNP level at admission. Median NT-proBNP was 1,364 ng/L, ranging from 46 to 70,000 ng/L. NT-proBNP was elevated in 63 (89%) patients and was ≥1,000ng/L in 42 (59%). Log NT-proBNP (hazard ratio [HR] 3.51, 95% confidence interval [CI] 1.55-7.97, P=0.003) and left ventricular ejection fraction (HR 0.95, 95%CI 0.91-0.99, P=0.007) were predictors for all-cause mortality. Log NT-proBNP was the only independent significant predictor of cardiovascular mortality. In-hospital mortality was 0% for patients with NT-proBNP <1,000, but 17% for those with NT-proBNP ≥1,000 (P=0.036). CONCLUSIONS: NT-proBNP is a strong predictor of outcome in patients undergoing acute LM coronary artery stenting. Mortality in such patients is high, but those with NT-proBNP < 1,000ng/L may have a favorable short- and long-term prognosis. Further research, including a larger patient population, is needed to determine the optimal cut-off value for NT-proBNP in patients undergoing acute LM coronary artery intervention.

Augmented reality-based navigation increases precision of pedicle screw insertion.

BACKGROUND: Precise insertion of pedicle screws is important to avoid injury to closely adjacent neurovascular structures. The standard method for the insertion of pedicle screws is based on anatomical landmarks (free-hand technique). Head-mounted augmented reality (AR) devices can be used to guide instrumentation and implant placement in spinal surgery. This study evaluates the feasibility and precision of AR technology to improve precision of pedicle screw insertion compared to the current standard technique. METHODS: Two board-certified orthopedic surgeons specialized in spine surgery and two novice surgeons were each instructed to drill pilot holes for 40 pedicle screws in eighty lumbar vertebra sawbones models in an agar-based gel. One hundred and sixty pedicles were randomized into two groups: the standard free-hand technique (FH) and augmented reality technique (AR). A 3D model of the vertebral body was superimposed over the AR headset. Half of the pedicles were drilled using the FH method, and the other half using the AR method. RESULTS: The average minimal distance of the drill axis to the pedicle wall (MAPW) was similar in both groups for expert surgeons (FH 4.8 ± 1.0 mm vs. AR 5.0 ± 1.4 mm, p = 0.389) but for novice surgeons (FH 3.4 mm ± 1.8 mm, AR 4.2 ± 1.8 mm, p = 0.044). Expert surgeons showed 0 primary drill pedicle perforations (PDPP) in both the FH and AR groups. Novices showed 3 (7.5%) PDPP in the FH group and one perforation (2.5%) in the AR group, respectively (p > 0.005). Experts showed no statistically significant difference in average secondary screw pedicle perforations (SSPP) between the AR and the FH set 6-, 7-, and 8-mm screws (p > 0.05). Novices showed significant differences of SSPP between most groups: 6-mm screws, 18 (45%) vs. 7 (17.5%), p = 0.006; 7-mm screws, 20 (50%) vs. 10 (25%), p = 0.013; and 8-mm screws, 22 (55%) vs. 15 (37.5%), p = 0.053, in the FH and AR group, respectively. In novices, the average optimal medio-lateral convergent angle (oMLCA) was 3.23° (STD 4.90) and 0.62° (STD 4.56) for the FH and AR set screws (p = 0.017), respectively. Novices drilled with a higher precision with respect to the cranio-caudal inclination angle (CCIA) category (p = 0.04) with AR. CONCLUSION: In this study, the additional anatomical information provided by the AR headset superimposed to real-world anatomy improved the precision of drilling pilot holes for pedicle screws in a laboratory setting and decreases the effect of surgeon's experience. Further technical development and validations studies are currently being performed to investigate potential clinical benefits of the herein described AR-based navigation approach.

Reinterventions after dynamic intraligamentary stabilization in primary anterior cruciate ligament repair.

BACKGROUND: The goal of this study was to perform an in-depth analysis of the frequency and cause of secondary interventions subsequent to primary anterior cruciate ligament (ACL) repair with dynamic intraligamentary stabilization (DIS). METHODS: Between July 2009 and June 2014, 455 patients underwent DIS treatment. The minimum follow-up was 21months (mean 28months, range 21-64months). RESULTS: A total of 215 (48.2%) reinterventions were performed in 190 (42.6%) patients. One-hundred and seventy-six (39.4%) were non-revision reinterventions, and 39 (8.7%) were revision ACL reconstructions. Re-arthroscopies included 26 (5.8%) scar tissue debridements with hardware removal due to range of motion deficits, 14 (3.1%) partial meniscectomies, four (0.9%) meniscal sutures, and four (0.9%) arthroscopies due to crepitation or knee pain. Minor non-revision reinterventions performed under analgosedation consisted of 97 (21.7%) hardware removals, 20 (4.5%) hardware removals with manipulations under anesthesia, and four manipulations under anesthesia alone (0.9%). CONCLUSIONS: In our study, the revision rate was within the range of published results after ACL reconstructions. In over 90% of patients, the native ACL was preserved with no need for a secondary reconstruction. Most of the non-revision reinterventions were minor and included hardware removals and manipulations under anesthesia. The re-arthroscopy rate was lower than that after ACL reconstruction with fewer secondary meniscal sutures and partial meniscectomies. Early treatment of meniscal tears may be one crucial benefit of ACL repair with DIS.

Augmented Reality-Guided Lumbar Facet Joint Injections.

OBJECTIVES: The aim of this study was to assess feasibility and accuracy of augmented reality-guided lumbar facet joint injections. MATERIALS AND METHODS: A spine phantom completely embedded in hardened opaque agar with 3 ring markers was built. A 3-dimensional model of the phantom was uploaded to an augmented reality headset (Microsoft HoloLens). Two radiologists independently performed 20 augmented reality-guided and 20 computed tomography (CT)-guided facet joint injections each: for each augmented reality-guided injection, the hologram was manually aligned with the phantom container using the ring markers. The radiologists targeted the virtual facet joint and tried to place the needle tip in the holographic joint space. Computed tomography was performed after each needle placement to document final needle tip position. Time needed from grabbing the needle to final needle placement was measured for each simulated injection. An independent radiologist rated images of all needle placements in a randomized order blinded to modality (augmented reality vs CT) and performer as perfect, acceptable, incorrect, or unsafe. Accuracy and time to place needles were compared between augmented reality-guided and CT-guided facet joint injections. RESULTS: In total, 39/40 (97.5%) of augmented reality-guided needle placements were either perfect or acceptable compared with 40/40 (100%) CT-guided needle placements (P = 0.5). One augmented reality-guided injection missed the facet joint space by 2 mm. No unsafe needle placements occurred. Time to final needle placement was substantially faster with augmented reality guidance (mean 14 ± 6 seconds vs 39 ± 15 seconds, P < 0.001 for both readers). CONCLUSIONS: Augmented reality-guided facet joint injections are feasible and accurate without potentially harmful needle placement in an experimental setting.

Reconstrucción anatómica del Acromion en casos de fracturas traumáticas y posterior a artroplastia reversa del Hombro. Reporte de Casos / Anatomic reconstruction of the acromion in cases of traumatic fractures after reverse shoulder arthroplasty. Report of a series of cases

Introducción Tanto las fracturas traumáticas del acromion, así como las fracturas acromiales por insuficiencia posterior a artroplastia reversa del hombro, son entidades poco frecuentes. Con la ampliación des los criterios operativos para la artroplastia reversa del hombro, es de suponer un aumento en el caso des las fracturas acromiales por insuficiencia posteriores a dicho procedimiento quirúrgico. Al ser estas entidades poco frecuentes hacen falta en la literatura recomendaciones basadas en la evidencia para el manejo de estas, las cuales representan un reto para el especialista tratante. Materiales y Métodos Reporte de seis casos entre 2013 y 2016 en el hospital cantonal de Frauenfeld (Suiza) de dos grupos de pacientes con fracturas del Acromion. En el grupo A se clasificaron tres pacientes que presentaron fractura por insuficiencia del acromion posterior a artroplastia reversa del Hombro. En el grupo B clasificaron tres pacientes con fracturas traumáticas del acromion en las cuales el manejo conservador no fue exitoso. Los dos grupos de pacientes fueron sometidos al mismo método quirúrgico con reducción abierta y reconstrucción anatómica del Acromion por medio de fijación con placa y tornillos interfragmentarios. Resultados Posterior a la intervención quirúrgica, la función del hombro se recuperó en todos los pacientes del Grupo A. La flexión anterior aumentó en promedio de 53° a 127°, y la abducción mejoró de 52° a 125°. Las mediciones posteriores al año de la intervención mostraron puntajes constantes entre 55-71, así como un valor subjetivo de hombro (SSV) de 50-90. En el Grupo B, el rango de movimiento preoperatorio se mantuvo constante. La flexión hacia delante mejoró de 133° a 157° y la abducción aumentó de 147° a 153°. Un año después de la cirugía, los puntajes de Constant en el grupo B variaron de 70 a 86 y el SSV se encontró entre 80 a 100. Los tres pacientes del Grupo B consiguieron retomar sus actividades diarias sin dolor y pudieron regresar al trabajo. La extracción de la placa fue necesaria en la mitad de los pacientes de la cohorte (Grupo A n=1, Grupo B n=2). Discusión La fractura del acromion es una condición seria que puede causar daño significativo al funcionamiento del hombro. Tanto en pacientes con ARH así como en pacientes sin ARH previa, nuestra técnica operativa abierta de reconstrucción anatómica del acromion mostró buenos resultados. Recomendamos el manejo quirúrgico por medio de reconstrucción con placa y clavos de fijación. Nivel de evidencia: IV

Aim To propose a surgical technique to treat the traumatic acromion fractures, as well as acromion fractures before reverse total Shoulder Replacement (TSR). Methods Six patients were treated with the same fixation technique between December 2013 and December 2016. Three patients had acromial insufficiency fractures (type II) following TSR (Group A). The other three patients, who had traumatic acromion fractures, underwent unsuccessful conservative treatment (Group B). Surgical treatment involved reconstruction of the acromion using an open technique with plate and interfragmentary screw fixation. Results Following reconstruction, shoulder function was regained in all patients in Group A. Forward flexion increased, on average, from 53° to 127°, and abduction improved from 52° to 125°. Measurements at one-year follow-up were Constant scores from 55-71, and subjective shoulder value (SSV) from 50-90. In Group B, preoperative range of motion was not substantially diminished. Forward flexion improved from 133° to 157°, and abduction increased from 147° to 153°. One year following surgery, the Constant scores in Group B ranged from 70-86, and SSV was 80-100. All three patients performed daily activities without pain, and were able to return to work. Plate removal was necessary in half the patients in the cohort (Group A n=1; Group B n=2). Conclusion An acromion fracture is a serious condition that can cause significant damage to shoulder functioning. In patients with or without previous TSR, this fixation technique was used successfully to reconstruct the anatomic lateral and basal acromion. Evidence Level: IV