Pediatric Supracondylar Humeral Fractures Research Articles

Cubitus varus deformity following paediatric supracondylar humeral fracture remodelling predominantly in the sagittal direction: A three-dimensional analysis of eighty-six cases.

Three-dimensional (3D) capacity for remodelling in cubitus varus deformity (CVD) after paediatric supracondylar humeral fractures (PSHFs) remains unelucidated. This study investigated remodelling patterns after PSHFs by examining 3D deformity distribution over time after injury. Computed tomography (CT) data of 86 patients with CVD after PSHFs were analysed. The 3D deformity angles in the sagittal, coronal, and axial directions were assessed and correlated with the duration between the age at injury and CT evaluation. For the subgroup analysis, we performed the same correlation analysis in a younger (< 8 years old) and an older group (≥ 8 years old); we categorized the duration into early (< 2 years), middle (≥ 2 to < 5 years), and late periods (≥ 5 years) and compared the deformity angles of each direction among the three groups. Sagittal deformity showed a moderate correlation with the duration of deformity (r = -0.54; P < 0.001), while coronal and axial deformities showed a negligible correlation. Sagittal deformity showed moderate correlations with the duration in the younger group (r = -0.62; P < 0.001) and weak correlations in the older group (r = -0.37; P = 0.091). In the sagittal direction, the deformity angle in the early period was significantly larger than those in the mid and late periods (P < 0.001). However, there were no significant differences among the three groups in the coronal and axial directions. Sagittal deformities in CVDs are capable of remodelling, especially in the early period and at a younger age, whereas coronal and axial deformities are less likely to undergo remodelling.

Associated Factor and Long-Term Clinical Outcomes for Patients with Postoperative Rotational Malreduction in Pediatric Supracondylar Humeral Fractures.

Background and Objectives: Long-term outcomes of immediately postoperative rotational malreduction in the axial plane after operative treatment of supracondylar humeral fractures (SCHF) are unknown. This study aimed to investigate the long-term clinical outcomes and associated factors for immediately postoperative rotational malreduction of SCHF. Materials and methods: In this retrospective case-control study, 88 patients who underwent surgery for Gratland type III SCHF were enrolled between January 2012 and January 2020. Among them, 49 patients had immediately postoperative malrotational reduction (rotational malreduction group) and 39 patients had no rotational deformity (control group). To evaluate the associated factors for immediately postoperative rotational malreduction, demographic data, fracture patterns, physical examination signs, and preoperative radiological parameters were analyzed. To compare the clinical outcomes, operation time, range of motion of the elbow, time from operation to full range of motion, and Flynn criteria were evaluated. The Oxford elbow score was used to investigate long-term clinical outcomes for patients five years after operation. Results: The mean age was 5.7 ± 2.3 years and mean follow-up period was 15.7 ± 4.0 months. The rotational malreduction group had significantly more patients with oblique fracture pattern (p = 0.031) and Pucker sign (p = 0.016) and showed a significantly longer operative time (p = 0.029) than the control group. Although there was no significant difference in the range of elbow motion and the Flynn criteria, the Kaplan-Meier survival curve showed a longer time to recover the full range of elbow motion in the rotational malreduction group (p = 0.040). There were no significant differences in the long-term clinical outcomes assessed using the Oxford elbow score (p = 0.684). Conclusions: Oblique fracture pattern and Pucker sign may be associated with immediately postoperative rotational malreduction in the axial plane. Although patients with immediately postoperative rotational malreduction showed favorable results of long-term clinical outcomes, they required more weeks to recover the full range of elbow motion.

A new configuration of lateral-pin fixation for pediatric supracondylar humeral fracture: A biomechanical analysis.

The aim of this study was to biomechanically compare a new lateral-pinning technique, in which pins engage the medial and lateral columns of the distal humerus in a divergent configuration in both the axial and sagittal planes instead of the coronal plane, with the cross-pin, and with 2 and 3 coronally divergent lateral-pin techniques in a synthetic humerus model of supracondylar humerus fractures. Thirty-six identical synthetic models of the humerus simulating a standardized supracondylar humerus fracture were included in this study. They were divided into 4 groups based on the pin configuration of fixation: the new 3-lateral pin-fixation technique (group A), 2 crossed pins (group B), 3 divergent lateral pins (group C), and 2 divergent lateral pins (group D). Each model was subjected to combined axial and torsional loading, and then torsional stability and torsional stiffness (Nmm/°) were recorded. Group A had greater rotational stability than groups C and D but had no statistically significant additional rotational stability compared with group B (P=.042, P=.008, P=.648, respectively), whereas group B had greater rotational stability than only group D (P=.020). Furthermore, group A demonstrated higher internal rotational stiffness compared with groups C and D (P=.038, P=.006, respectively). Group B had better internal rotational stiffness than group D (P=.015). There was no significant difference in internal rotational stiffness between groups A and B (P=. 542), groups B and C (P=.804), and groups D and C (P=.352). Although no statistically significant differences existed between groups A and B, the modified pin configuration exhibited the highest torsional stability and stiffness. Group D showed the lowest values in all biomechanical properties. This study has shown us that this new lateral-pinning technique may provide torsional resistance to internal rotational displacement as strong as the standard technique of crossed-pin configuration of fixation. Furthermore, with this new pin configuration, greater torsional resistance can be obtained than with either the standard 2- or the standard 3-lateral divergent pin configuration. Cite this article as: Bilgili F, Demirel M, Birişik F, Balcı Hİ, Sunbuloglu E, Bozdag E. A new configuration of lateral-pin fixation for pediatric supracondylar humeral fracture: A biomechanical analysis. Acta Orthop Traumatol Turc., 2023 10.5152/j.aott.2024.21091 [Epub Ahead of Print].

The effects of postoperative malrotation alignment on outcomes of Gartland type III/IV paediatric supracondylar humeral fractures treated by close reduction and percutaneous K-wire fixation

PurposeIn this study, we aimed to investigate the effects of postoperative malrotation alignment on the outcomes of Gartland type III/IV paediatric supracondylar humeral fracture (SCHF) treated by close reduction and percutaneous K-wire fixation.MethodsBetween January 2014 and December 2021, 295 Gartland type III/IV paediatric SCHFs treated by close reduction and percutaneous K-wire fixation were selected for this retrospective study. The demographic, clinical and radiographic parameters of all cases were collected. The lateral rotation percentage (LRP) was measured on X-rays to evaluate postoperative malrotation alignment of the fracture. All cases were categorized into 4 groups according to LRP: LRP ≤ 10% (210, 71.2%), 10% < LRP ≤ 20% (41, 13.9%), 20% < LRP ≤ 30% (26, 8.8%) and LRP > 30% (18, 6.1%). The carrying angle, ranges of multidirectional motions, Mayo Elbow Performance Score (MEPS) and Flynn’s Standard Score (FSS) of the injured elbow were assessed 6 months postoperation and compared among different groups. ROC analysis based on LRP and the excellent/good rate of FSS was performed to determine the acceptable maximum degree of postoperative malrotation alignment.ResultsThere was no difference in the demographic characteristics (age, sex, injured side and fracture type), postoperative Baumann angle, carrying angle or range of forearm rotation among the 4 groups (P > 0.05). The operation time and time from operation to K-wire removal were longer in the 20% < LRP ≤ 30% and LRP > 30% groups than in the LRP < 10% and 10% < LRP ≤ 20% groups (P < 0.001). The shaft condylar angle, range of elbow flexion, MEPS and FSS of the injured elbow 6 months postoperatively were lower in the 20% < LRP ≤ 30% and LRP > 30% groups than in the LRP < 10% and 10% < LRP ≤ 20% groups (P < 0.001). ROC analysis based on LRP and the excellent/good rate of FSS showed an area under the curve of 0.959 (95% CI 0.936–0.983), with a cutoff value of 26.5%, sensitivity of 95.3% and specificity of 90.1%.ConclusionA certain degree of residual malrotation alignment deformity of the SCHF may reduce the shaft condylar angle and extend the time from operation to removing the K-wire and affect elbow function, especially the range of elbow flexion. The acceptable maximum degree of residual malrotation deformity expressed as the LRP value was 26.5%.

Comparison of complications and results of early vs. delayed surgery for pediatric supracondylar humeral fractures.

Pediatric supracondylar humerus fracture (SCHF) is one of the most common elbow fractures in children aged 5-7 years. There is a continuous discussion regarding the optimal timing for conducting surgery for fractures of this nature. Therefore, we aimed to determine whether the timing of surgery in pediatric SCHFs has an impact on the frequency of early postoperative complications. Between January 2018 and March 2020, pediatric SCHF patients who underwent surgery at our hospital were retrospectively reviewed. Patients operated on within 12 hours after the fracture and those operated on later were respectively included in the early and late groups. Early postoperative complications, including neurological deficits, iatrogenic ulnar nerve injury, vascular injury, compartment syndrome, K-wire migration, and unexpected returns to the operating room, were compared between the two groups. We investigated surgical duration, reduction, and perioperative radiographic data. For modified Gartland type II or type III fractures, there was no significant difference in the incidence of early complications between the early and delayed groups. Additionally, there were no noticeable differences between the two groups in terms of perioperative radiographic data, reduction procedure, or surgical duration. Delayed surgery in type II or type III supracondylar humerus fractures was not associated with an increased incidence of early postoperative complications. The difficulty or effectiveness of reduction is not influenced by the timing of surgery.

The Effect of Fracture Patterns, Pinning Configuration, Surgeon Experience and Subspecialty on Short-Term Radiological Outcomes of Pediatric Supracondylar Humeral Fractures Treated in the Prone Position: A Case-Series.

The most common treatment modality for supracondylar humerus fractures (SCHFs) in children is closed reduction and percutaneous pinning (CRPP). Nonetheless, debate persists regarding the optimal technique used. Therefore, the purpose of our study was to investigate the impact of surgeon experience, surgeon subspecialty and pin configuration on short-term radiological outcomes following CRPP of displaced SCHFs. Patients less than 14 years of age who underwent CRPP for displaced SCHFs in the prone position between January 2018 and December 2022 were analyzed. Patients were separated into subgroups based on fracture type (low vs. high sagittal), pin configuration (lateral, cross, other), number and configuration of K-wires and first operator surgical experience. The following outcome measurements were collected: postoperative Baumann angle (BA), Shaft-Condylar angle (SCA), surgical duration (SD), duration of radiation exposure (DRE) and number of clinical and radiological follow-ups (FU). A total of 44 patients with a mean age of 6 ± 2.5 years were included in the final analysis. The mean post-operative BA and SCA were 74.8° ± 4.9° and 37.7° ± 10.2°, respectively. No significant differences were found in the post-operative Baumann's angle or SCA among the subgroups. Regarding secondary outcomes, no differences were found among each subgroup regarding SD, DRE and FUs. Short-term radiological outcomes following the treatment of SCHFs treated in the prone position are not affected by fracture patterns and pinning configuration, regardless of the surgeon's years of experience or subspecialty.

Do K-wire Configurations and Numbers Have Effects on Gartland Type 3 Pediatric Supracondylar Humeral Fractures?

Purpose: The purpose of this study was to compare pin configuration effects on early secondary displacement in the surgical treatment of pediatric supracondylar humeral fractures (SCHF).&#x0D; &#x0D; Methods: The study consisted of 100 (68M, 32F) children who underwent surgery between 2010 and 2013 for Gartland Type 3 (SCHF). The patients were divided into five groups according to the top configurations. The average age at the time of injury was 7.34 (between 2 and 14 years). Bauman angle (BA), Humerocapital angle (HCA), Anterior humeral line (AHL), flexion range, extension range, and Carrying angle (CA) were compared at preoperative, postoperative 1st-day, postoperative last control, and non-operated side. &#x0D; &#x0D; Results: There was no statistical difference between all five subgroups in terms of BA, AHL, HCA, and CA were the same on postoperative 1st-day and postoperative last control. Also, there was no statistically significant difference was observed between age, sex, and type of fracture. Five of the cases have pin site infection and in three patients occurred ulnar nerve injury due to initial trauma. &#x0D; &#x0D; Conclusion: After a good and gentle reduction and early treatment of pediatric SCHF, all pin configurations maintain alignment. All pin configurations can be used for stabilization.

Modified lateral approach combined with medial percutaneous approach versus triceps tongue-shaped flap approach and bilateral triceps brachii approach for pin fixation in treatment of irreducible displaced pediatric supracondylar humeral fractures.

To evaluate the clinical outcomes of the modified lateral approach combined with the medial percutaneous approach (MLACMPA) versus the triceps tongue-shaped flap approach (TTSFA) and the bilateral triceps brachii approach (BTBA) in the treatment of irreducible displaced supracondylar humeral fractures (SHFs) in children. Between March 2000 and July 2022, a total of 135 children who underwent open reduction and Kirschner wire cross internal fixation for irreducible displaced SHFs caused by trauma were retrospectively analyzed. According to the surgical approach, the patients were assigned to the TTSFA group (n = 36), the BTBA group (n = 40) and the MLACMPA group (n = 59). The duration of surgery, intraoperative blood loss, incision length, and elbow range of motion were compared. The 3 groups were similar in terms of mean age, sex distribution, and time from injury to operation. The duration of surgery, intraoperative blood loss, incision length and postoperative elbow range of motion in the MLACMPA group were significantly superior to those in the TTSFA group and BTBA group (P < .05). Compared the use of the TTSFA or the BTBA, using the MLACMPA for pin fixation in the treatment of irreducible displaced pediatric SHFs could significantly shorten the duration of surgery, reduce the operation trauma, facilitate earlier functional exercise of joints after operation and yield better elbow function.

Does a medial mini-incision decrease the risk of iatrogenic ulnar nerve injury in pediatric supracondylar humeral fractures treated with closed reduction and percutaneous pinning?: A retrospective cohort study: Erratum

Does a medial mini-incision decrease the risk of iatrogenic ulnar nerve injury in pediatric supracondylar humeral fractures treated with closed reduction and percutaneous pinning?: A retrospective cohort study: Erratum

Is radiological rotation measurement affected by the fracture pattern in pediatric supracondylar humeral fractures?

In supracondylar humerus fractures (SCHF), the most frequently used method to calculate rotation is the Gordon lateral rotation percentage (GLRP) defined by Gordon et al. However, this technique includes only typical fractures (49%-80% of all fractures) from the Johns Hopkins (J-H) fracture classification system. The aim of the study was to investigate (1) is Gordon criteria useful for John Hopkins subgroups of supracondylar fractures and (2) is Gordon criteria affected by internal and external rotation. This study was designed using four pediatric left humerus bones obtained from the Sawbone© company. For each bone, an osteotomy was made to mimic each of the J-H coronal fracture patterns. The cut bones were placed in a wooden rotation apparatus. The GLRP measurements were taken by five blinded observers. In the repeated measurements of the observers, <20° rotation typical and <30° medial oblique and lateral oblique fracture pattern were measured as within the limits of an acceptable amount of rotation according to the Gordon criteria. However, for high fracture pattern (HFP), ≤30° internal rotation and <60° external rotation were determined to be within the acceptable rotation criteria according to the Gordon criteria. All fracture patterns have different characteristics; however, based on the data of this study, the Gordon criteria can be used safely for typical, medial oblique, and lateral oblique fracture patterns but it is necessary to lower the acceptable rate of 50% for HFP.

Transfer Validity of Pediatric Supracondylar Humeral Fracture Pin Placement Practice on In-Theater Performance by Orthopedic Trainees Using an Augmented Reality Simulator: Protocol for a Pilot Interventional Cohort Study With a Retrospective Comparator Cohort.

Supracondylar humeral fractures (SCHF) are a common cause of orthopedic morbidity in pediatric populations across the world. The treatment of this fracture is likely one of the first procedures involving x-ray-guided wire insertion that trainee orthopedic surgeons will encounter in their career. Traditional surgical training methods of "see one, do one, teach one" are reliant on the presence of real-world cases and must be conducted within an operative environment. We have developed an augmented reality simulator that allows trainees to practice this procedure in a radiation-free environment at no extra risk to patients. This study aims to examine whether training on a simulator in addition to traditional surgical training improves the in-theater performance of trainees. This multicenter, interventional cohort study will involve orthopedic trainees from New Zealand in their first year of advanced training between 2019 and 2023. Advanced trainees with no simulator exposure who were in their first year in 2019-2021 will form the comparator cohort, while those in the years 2022-2023 will receive additional regular simulator training as the intervention cohort. The comparator cohort's performance in pediatric SCHF surgery will be retrospectively audited using routinely collected operative outcomes and parameters over a 6-month period. Data on the performance of the intervention cohorts will be collected in the same way over a comparable period. The data collected for both groups will be used to determine whether additional training with an augmented reality training shows improved real-world surgical outcomes compared to traditional surgical training. As of February 2022, a total of 8 retrospective comparator trainees have been recruited by email. The study is financially supported through an external grant from the Wishbone Orthopaedic Research Foundation of New Zealand (September 2021) and an internal research grant from the University of Otago (July 2021). This protocol has been approved by the University of Otago Health Ethics committee (reference HD21/087), and the study is due for completion in 2024. This protocol may assist other researchers conducting similar studies in the field. Australian New Zealand Clinical Trials Registry ACTRN12623000816651; https://tinyurl.com/mtdkecwb. DERR1-10.2196/38282.

Does radiation exposure during pediatric supracondylar humeral fracture surgery change according to the C-arm position? A comparison of two different techniques

IntroductionIn the surgical treatment of supracondylar humeral fractures (SHF), the surgeon has to stand right next to the fluoroscopy device, so it is very important to know how to use it in the most appropriate way to reduce radiation exposure. The aim of this study was to investigate the effect of using C-arm in uniplanar (inverted) and biplanar (standard-horizontal) configurations on (1) the radiation exposure to the surgeon, and (2) surgical time and fluoroscopy exposure time. Material and methodsThis prospective randomised study was conducted on 20 patients who underwent fluoroscopy during closed reduction and percutaneous pinning for a SHF. In the first configuration, the C-arm was inverted and the image intensifier was used as a surgical table. In the second configuration, the C-arm was used biplanar. The operations were performed by 5 surgeons, with each surgeon using each method only twice. During the operation, to find a value closed to direct radiation exposure measurement was made by attaching a dosimeter to the wrist and scatter radiation exposure was measured by attaching a dosimeter to the neck and waist of the surgeons. The operation time and fluoroscopy exposure time were determined. ResultsThe duration of operations performed with the biplanar C-arm position and the fluoroscopy exposure time in operations performed with the uniplanar method were found to be statistically significantly longer (p = 0.001). The measurements on the dosimeter worn on the neck of surgeons were found to be statistically significantly higher while using the uniplanar C-arm configuration (p = 0.001). There was no statistically significant difference between the dosimeter measurements on the wrists and waists of the surgeons and the C-arm configurations (p = 0.820; p = 0.185). ConclusionsAlthough the use of biplanar C-arm has no effect on radiation exposure to the surgeon's wrist, the most important advantages are that the neck area is exposed to less radiation and it shortens the fluoroscopy time so the use of a biplanar C-arm can be recommended. Level of evidenceLevel II

Pediatric Supracondylar Fracture of the Humerus with Sideward Displacement

Background: Supracondylar humeral fracture is probably the most common elbow fracture in children requiring surgical intervention. We observed a subtype of pediatric supracondylar humeral fracture with a sideward translation, without substantial displacement in the sagittal plane on initial radiographs. The purpose of this study was to calculate the incidence of this fracture subtype and suggest a modification to the standard operative technique, to achieve the desired fracture alignment and fixation. Methods: We reviewed the clinical records and radiographs of all pediatric patients with supracondylar humeral fractures surgically treated in our institution between the years 2006 and 2014. The fracture types, fixation configuration and any complications were recorded. Results: Overall, 263 consecutive patients were included. The incidence of supracondylar fracture of the humerus with solely sideward displacement was 6%. The fracture was characterized clinically and radiographically. We proposed a modification to the standard operative technique for this fracture subtype for successful closed reduction and percutaneous pinning. Conclusions: Special attention to this fracture subtype, including appropriate operating room setup and the application of a suitable reduction and pinning technique, has the potential to achieve successful results and avoid the need for open reduction.

Does a medial mini-incision decrease the risk of iatrogenic ulnar nerve injury in pediatric supracondylar humeral fractures treated with closed reduction and percutaneous pinning?: A retrospective cohort study: Erratum

Does a medial mini-incision decrease the risk of iatrogenic ulnar nerve injury in pediatric supracondylar humeral fractures treated with closed reduction and percutaneous pinning?: A retrospective cohort study: Erratum

Use of lateral-exit crossed-pin fixation for pediatric supracondylar humeral fractures: a retrospective case series.

Surgeons have been reluctant to perform crossed-pin fixation for displaced pediatric supracondylar humeral (SCH) fractures because it carries a risk of iatrogenic ulnar nerve injury. This study aimed to introduce lateral-exit crossed-pin fixation for displaced pediatric SCH fractures and to evaluate its clinical and radiological outcomes, with a particular focus on iatrogenic ulnar nerve injuries. Children who underwent lateral-exit crossed-pin fixation for displaced SCH fractures between 2010 and 2015 were retrospectively reviewed. Lateral-exit crossed-pin fixation involved the introduction of a medial pin from the medial epicondyle, as in the conventional method, followed by pulling the pin through the lateral skin until the distal and medial aspects of the pin were just under the cortex of the medial epicondyle. The time to union and loss of fixation were assessed. Flynn's clinical criteria (cosmetic and functional factors) and complications including iatrogenic ulnar nerve injury were investigated. A total of 81 children with displaced SCH fractures were treated with lateral-exit crossed-pin fixation. All but one patient achieved union with good alignment, with an average time to union of 7.9 weeks (3.9-10.3 weeks). Only one patient exhibited cubitus varus deformity associated with loss of reduction. All patients recovered to almost their full range of motion. No case of iatrogenic ulnar nerve injury developed; however, iatrogenic radial nerve injury developed in one patient. Lateral-exit crossed-pin fixation provides sufficient stability with a lower risk of iatrogenic ulnar nerve injury in children with displaced SCH fractures. This method is an acceptable technique for crossed-pin fixation.

THE OUTCOME OF IRREDUCIBLE PULSELESS SUPRACONDYLAR FRACTURE OF HUMERUS TREATED VIA ANTERIOR APPROACH – A CASE SERIES

Background: Treatment of a pulseless pediatric supracondylar humeral fracture is controversial and varies from closed reduction percutaneous pinning to Surgical Exploration. Present study aimed to analyze outcome of Irreducible pulseless supracondylar fractures treated with Open reduction and exploration via anterior approach. in this prospective study of 7 patients Method: with pulseless Supracondylar fracture, 2 were treated by Close reduction percutaneous pinning and the other 5, irreducible on table by Open intervention. The later 5 cases were followed up at 3 weeks, 6 weeks, and 3 months and functionally assessed using MEPS. 3 cases Results: showed immediate return of pulse, 2 recovered within 6 hours. All cases at 3 months showed MEPS &gt;90. Anterior approach is excellent Conclusion: for surgical decompression of the neurovascular bundle.

Clinical and radiographic outcomes after paediatric supracondylar humeral fractures treated with combined intramedullary and lateral wire fixation: our experience in fifty-one cases.

Displaced supracondylar humerus fractures in children are known for their high rate of complications and require urgent surgical treatment. Basically, there are two methods of fracture fixation: the lateral pin technique and the crossed pin technique. However, the best technique remains debated. The aim of this study was to evaluate the clinical and radiographic outcomes of our method of fixation using combined intramedullary and lateral wires for treatment of displaced supracondylar humeral fractures in paediatric patients. Fifty-one paediatric patients were treated for displaced supracondylar humeral fractures. The method of fracture fixation used consists of two Kirschner wires inserted one intramedullary and the other laterally. Clinical and radiographic outcomes were assessed at last follow-up. According to Gartland's classification, 17 fractures (33%) were type 2 and 34 (67%) were type 3. The mean follow-up period was 7.8months. Functional outcome according to Flynn's criteria was satisfactory in all cases with 92% graded as excellent or good. Cosmetic outcome according to Flynn's criteria was satisfactory in all cases. Radiologically, at last follow-up, the mean Baumann angle was 69° (63-82°) and the mean lateral capitellohumeral angle was 41° (32-50°). Patients managed with combined intramedullary and lateral wires experience satisfactory results. Moreover, this technique, without risk for the ulnar nerve, can be interesting in the treatment of infrafossal fractures and fractures with anterior displacement.

Incidence, risk factors, and consequences of radiographic pin migration after pinning of pediatric supracondylar humeral fractures.

Current literature on pin migration is inconsistent and its significance is not understood. We aimed to investigate the incidence, magnitude, predictors, and consequences of radiographic pin migration after pediatric supracondylar humeral fractures (SCHF). We retrospectively reviewed pediatric patients treated with reduction and pinning of SCHF at our institution. Baseline and clinical data were collected. Pin migration was assessed by measuring the change in distance between pin tip and humeral cortex on sequential radiographs. Factors associated with pin migration and loss of reduction (LOR) were assessed. Six hundred forty-eight patients and 1506 pins were included; 21%, 5%, and 1% of patients had pin migration ≥5 mm, ≥10 mm, and ≥20 mm respectively. Mean migration in symptomatic patients was 20 mm compared to a migration of 5 mm in all patients with non-negligible migration ( P < 0.001). Pin migration > 10 mm was strongly associated with LOR [odds ratio (OR) = 6.91; confidence interval (CI), 2.70-17.68]. Factors associated with increased migration included increased days to pin removal ( β = 0.022; CI, 0.002-0.043), migration outwards versus inwards ( = 1.02; CI, 0.21-1.80), and BMI > 95th percentile (OR = 1.63; [1.06-2.50]). Factors not associated with migration included cross-pinning, number of pins, and fracture grade. In summary, we identified a 5% incidence of radiographic pin migration ≥ 10 mm and determined the factors associated with it. Pin migration became radiographically significant at >10 mm where it was strongly associated with LOR. Our findings contribute to the understanding of pin migration and suggest that interventions targeting pin migration may decrease the risk of LOR. Level of Evidence: Level III - Retrospective Cohort Study.

PROTOCOL FOR EXAMINING TRANSFER VALIDITY OF A SUPRACONDYLAR HUMERAL FRACTURE PINNING AUGMENTED REALITY SIMULATOR

Augmented reality simulators offer opportunities for practice of orthopaedic procedures outside of theatre environments. We developed an augmented reality simulator that allows trainees to practice pinning of paediatric supracondylar humeral fractures (SCHF) in a radiation-free environment at no extra risk to patients. The simulator is composed of a tangible child's elbow model, and simulated fluoroscopy on a tablet device. The treatment of these fractures is likely one of the first procedures involving X-ray guided wire insertion that trainee orthopaedic surgeons will encounter. This study aims to examine the extent of improvement simulator training provides to real-world operating theatre performance.This multi-centre study will involve four cohorts of New Zealand orthopaedic trainees in their SET1 year. Trainees with no simulator exposure in 2019 - 2021 will form the comparator cohort. Trainees in 2022 will receive additional, regular simulator training as the intervention cohort. The comparator cohort's performance in paediatric SCHF surgery will be retrospectively audited using routinely collected operative outcomes and parameters over a six-month period. The performance of the intervention cohorts will be collected in the same way over a comparable period. The data collected for both groups will be used to examine whether additional training with an augmented reality simulator shows improved real-world surgical outcomes compared to traditional surgical training. This protocol has been approved by the University of Otago Health Ethics committee, and the study is due for completion in 2024.This study is the first nation-wide transfer validity study of a surgical simulator in New Zealand. As of September 2022, all trainees in the intervention cohort have been recruited along with eight retrospective trainees via email. We present this protocol to maintain transparency of the prespecified research plans and ensure robust scientific methods. This protocol may also assist other researchers conducting similar studies within small populations.

Does posterior approach always lead to poor functional and cosmetic outcomes in displaced pediatric supracondylar humeral fractures?

Supracondylar humerus fractures (SCHFs) are the most common types of elbow fractures in children. Closed reduction percutaneous pinning (CRPP) is the primary surgical treatment of SCHFs. In cases that cannot be managed with closed reduction, treatment with open reduction and internal fixation (ORIF) is necessary. We aimed to compare CRPP and ORIF through a posterior approach regarding clinical and functional outcomes in pediatric SCHF cases. Patients with Gartland type III SCHF who underwent CRPP or ORIF with posterior approach at our clinic between January 2013 and December 2016 were included in this retrospective study. A total of 60 patients who underwent surgical treatment and had available data on our hospital database and no additional injuries were included in the study. We analyzed their data concerning age, gender, fracture type, neurovascular damage, and surgical treatment. In addition, we inspected the patients' anteroposterior and lateral radiographs at 1-year follow-up visits for Baumann (humerocapitellar) angle (BA) and carrying angle (CA) and checked their go-niometer assessments of elbow range of motion (ROM). The cosmetic and functional outcomes were determined using Flynn's criteria. Demographic, preoperative, and post-operative data of 60 patients between the ages of 2-15 were analyzed. 46 of these patients had CRPP, and 14 had posterior ORIF. CA, Baumann angle, and lateral capitello-humeral angle were measured for fractured elbow and contralateral elbow and compared statistically. There was no statistically significant difference between the two surgical ap-proaches in terms of CA (p=0.288), Baumann's angle (p=0.951) and LHCA (p=0.578). At the end of 1-year follow-up, elbow ROM was measured, and there was no statistically significant difference between the two groups (p=0.190). Furthermore, there is no statistically significant difference between the two surgical approaches in terms of both cosmetic (p=0.814) and functional (p=0.319) outcomes. A comprehensive literature review of pediatric SCHF shows that surgeons do not frequently prefer posterior incisions in Gartland type III fracture that cannot be managed with closed reduction. However, posterior open reduction is a safe and effective method since it provides more control over the distal humerus, allows for a complete anatomical reduction involving both cortices, reduces the risk of ulnar nerve injury, thanks to the nerve exploration, and yields positive cosmetic and functional outcomes.