Osteosynthesis of supracondylar humerus fractures in children: a biomechanical comparison of four techniques

Beneficial Perioperative Aspects Favor the Use of Percutaneous Crossed Pinning over Antegrade Nailing in Pediatric Supracondylar Fractures-A Retrospective Comparative Study

(1) Background: Displaced supracondylar humeral fractures in pediatric patients can be treated by either antegrade nailing (AN) or percutaneous crossed pinning (PCP). The aim of this study was to compare the intra- and perioperative management, complications and outcome of AN and PCP. (2) Methods: This retrospective study enrolled 271 individuals (median age 5 years, IQR 4-7 years) who underwent AN (n = 173) or PCP (n = 98). Patient history was analyzed for incidence of nerve injuries, postoperative treatment, postoperative malrotation, time of hospital stay, time to implant removal and revision rate. Operative procedures were investigated for duration and radiation exposure. (3) Results: PCP was associated with a significantly lower radiation exposure (dose area product: PCP mean 20.1 cGycm² vs. AN mean 34.7 cGycm², p < 0.001; fluoroscopy time: PCP mean 1.1 min, range 0.1-8.1 min, vs. AN mean 1.5 min, range 0.1-7.1 min, p < 0.001), duration of surgery (PCP mean 32.2 min vs. AN mean 48.3 min, p < 0.001) and time to implant removal (PCP mean 37 days vs. AN mean 113 days, p < 0.001). Cast removal was performed earlier in the AN group (PCP mean 30.2 days vs. AN mean 20.4 days, p < 0.001) and there were fewer iatrogenic nerve lesions (PCP: 24% vs. AN: 8%, p < 0.001). (4) Conclusions: In the investigated study population, the analyzed parameters seem to favor the use of PCP. The advantages of AN should be weighed against its drawbacks. For special indications, AN remains a relevant technique in supracondylar fracture treatment, and surgeons should be familiar with this procedure.

Treatment of grossly dislocated supracondylar humerus fractures after failed closed reduction: a retrospective analysis of different surgical approaches

INTRODUCTION

The supracondylar humerus fracture (SCHF) is one of the most common pediatric injuries. Highly displaced fractures can be very challenging. If closed reduction fails, the therapy algorithm remains controversial.

MATERIALS AND METHODS

In total, 41 patients (21 boys and 20 girls) with irreducible Gartland type III SCHF, treated with open reduction through three different approaches and cross-pin fixation, were retrospectively evaluated. The mean follow-up was 46 months (min.: 12, max.: 83, SD: 23.9). The Mayo elbow performance score (MEPS) as well as the quick disabilities of arm, shoulder and hand (qDASH) score were used to assess the functional outcome. Baumann's angle and the anterior humeral line (AHL, Roger's line) were obtained from follow-up radiographs. Time to surgery, postoperative nerve-palsy, rate of revision surgery, and complication rate were examined.

RESULTS

Two revision surgeries were reported. One due to inadequate reduction and one due to secondary loss of reduction. In this context, the AHL was a sufficient tool to detect unsatisfactory reduction. According to the MEPS the functional outcome was excellent (> 90) in 37/41 patients and good (75-89) in 4/41 at the final visit. Fair or poor results were not documented. The qDASH score was 1.8 (min.: 0, max.: 13.6, SD: 3.4). There were no significant differences between the utilized surgical approaches. An iatrogenic injury of the ulnar nerve was not reported in any case. Overall, one heterotopic ossification without impairment of the range of motion and one preliminary affection of the radial nerve were documented.

CONCLUSION

In the rare case of an irreducible SCHF, an anatomical reduction can be achieved by open approaches with excellent functional outcome and a high grade of patient satisfaction. All described open approaches can be utilized with a high safety-level.

Spontaneous humeral torsion deformity correction after displaced supracondylar fractures in children

BACKGROUND

After displaced supracondylar humerus fractures (SCHF) in children, residual deformities are common with cubitus varus (CV) being the clinically most visible. Distal fragment malrotation may lead to instability, fragment tilt and subsequent CV. Detection and assessment of malrotation is difficult and the fate of post-traumatic humeral torsion deformity is unknown. The aim of this study was to evaluate the incidence of humeral torsion differences in children with surgically treated SCHF and to observe spontaneous changes over time.

METHODS

A cohort of 27 children with displaced and surgically treated SCHF were followed prospectively from the diagnosis until twelve months after trauma. Clinical, photographic, sonographic and radiological data were obtained regularly. Differences in shoulder and elbow motion, elbow axis, sonographic humeral torsion measurement and radiological evaluation focusing on rotational spur were administered.

RESULTS

Six weeks after trauma, 67% of SCHF children had a sonographically detected humeral torsion difference of > 5° (average 14.0 ± 7.6°). Of those, 44% showed a rotational spur, slight valgus or varus on radiographs. During follow-up, an average decrease of the difference from 14° (six weeks) to 7.8° (four months) to 6.5° (six months) and to 4.9° (twelve months) was observed. The most significant correction of posttraumatic humeral torsion occurred in children < 5 years and with internal malrotation > 20°.

CONCLUSION

After displaced and surgically treated SCHF, most children had humeral torsion differences of both arms. This difference decreased within one year after trauma due to changes on the healthy side or correction in younger children with severe deformity.

LEVEL OF EVIDENCE/CLINICAL RELEVANCE

Therapeutic Level IV.

The most stable pinning configurations in transverse supracondylar humerus fracture fixation in children: A novel three-dimensional finite element analysis of a pediatric bone model

PURPOSE

This study aimed at finding out the effect of exit height, trajectory and number of pins on the stability of cross and divergent-lateral pins used in the fixation of extension-type, transverse supracondylar humerus fracture (SHF) in children, based on finite element analysis.

METHODS

Distal humerus model consisting of the ossific nucleus of the capitellum (ONC) and distal cartilage of a 6-year-old boy was developed via three-dimensional finite modeling. Various cross and divergent-lateral pinning models with either two or three pins were simulated on an extension-type, transverse SHF and tested in six loading directions.

RESULTS

Two-cross pins and 2-divergent-lateral pins were more stable against torsional and translation forces respectively, while 3-cross pins were the most stable against all forces. The cross pins exiting at the upper border of the distal metaphyseal-diaphyseal junction (MDJ) had the best stiffness among the 2-cross pins, while the lateral pins with a middle third ONC distal pin provided the best stiffness among the 2-lateral pins. A third olecranon fossa pin greatly enhanced stability of the 2-lateral pins.

CONCLUSION

For typical transverse fractures, 2-cross pins are found to be superior to 2-divergent lateral pins only against torsional forces. Pins exiting at the upper border of the MDJ provides the best mechanical stability with 2-cross pins. Two-divergent-lateral pins with a distal pin going through the middle third of the ONC provides the best mechanical stability against translation forces for these transverse fractures. Three-cross pins however offer the best mechanical stability against both translation and torsional forces. This study offers important clues in the preoperative evaluation and management of extension-type supracondylar fractures in children.

Management of acute paediatric fractures treated surgically in the UK: a cross-sectional study

INTRODUCTION

The epidemiology of acute paediatric orthopaedic trauma managed surgically across the NHS is poorly described. Compliance against national standards for the management of supracondylar humeral fractures is also unknown at a national level.

METHODS

Collaborators in 129 NHS hospitals prospectively collected data on surgically managed acute paediatric orthopaedic trauma cases. Data were collected over a seven-day period and included demographics, injury characteristics, operative details and timing of surgery. A national audit was also undertaken to evaluate compliance with the British Orthopaedic Association Standards for Trauma Guideline 11: Supracondylar Fractures of the Humerus in Children.

RESULTS

Data were captured on 770 surgically treated cases. The three most common injuries were forearm fractures of both bones (n = 235), distal radius fractures (n = 194) and supracondylar elbow fractures (n = 89). The mode day of injury was Friday (n = 136) and the mode day of surgery was Saturday (n = 138). 88% of supracondylar fractures received surgery on the day of presentation or the following day. Only 14% of supracondylar fractures were treated surgically after 8pm; 33/89 used 2.0mm Kirschner wires, 38/89 used 1.6mm wires and 2/89 used 1.2mm wires.

CONCLUSION

Forearm fractures of both bones, distal radius fractures and supracondylar humeral fractures were the three most common injuries treated surgically. There is wide variation in compliance against national standards in the management of supracondylar humeral fractures with 88% undertaking surgery on the day of or the day following presentation but only 37% using the recommended 2.0mm Kirschner wires.

The effect of the angle between fracture line and Kirschner wires on stability in supracondylar humerus fractures treated with Kirschner wire fixation: A finite element analysis

Objectives

This study aims to investigate the effects of the angles created by the Kirschner wires (K-wires), which are applied in the percutaneous fixation of supracondylar humerus fractures with cross K-wire, with the fracture line on fracture stabilization.

Patients and methods

The study was conducted on distal humerus fracture models. Medial and lateral K-wires were placed in the fracture models. The angle between the fracture line and the K-wire inserted from medial was represented by alpha (α), while the angle between the fracture line and the K-wires inserted from lateral was represented by beta (β). A combination of various angles (30°, 45°, and 60°) was used in each model, where no two models had the same combination of α and β, resulting in nine different wire configurations. The simulation program was used to simulate the effects of forces, which were applied on rotation, flexion and extension directions, on these models. We measured and compared the stress on the wires and the displacement of fractures under different force configurations.

Results

When the force was applied in the counterclockwise direction, the stresses were 58 megaPascal (MPa) on medial K-wire, 24 MPa on lower lateral K-wire, and 45 MPa on upper lateral K-wire in (45°, 45°) wire configuration. When the force was applied in the clockwise direction, the stresses were 57 MPa on medial K-wire, 23 MPa on lower lateral K-wire, and 45 MPa on upper lateral K-wire in (45°, 45°) wire configuration. In all models, the increased α and β angles were translated into the decreased stress on K-wires at the fracture level and decreased displacement under rotational deforming forces. Despite having generally lower fracture displacement, the increased α and β angles led to variable changes in the stress on K-wires against flexion and extension forces.

Conclusion

In supracondylar humerus fractures, increasing the insertion angle of both medial and lateral K-wires augments stabilization and reduces displacement, particularly against rotational deforming forces.

[Technique and biomechanics of Kirschner wire osteosynthesis in children]

OBJECTIVE

Safe and stable fixation of metaphyseal and epiphyseal fractures by Kirschner (K-)wire osteosynthesis. Use of various K‑wire configurations depending on the fracture morphology.

INDICATIONS

In accordance with the AO Pediatric Comprehensive Classification of Long-Bone Fractures (PCCF), all Salter-Harris (SH) and metaphyseal fractures as well as fractures of the foot and hand independent of the reduction technique, closed or open, provided that adaptation osteosynthesis allows sufficient stability. Fixation/immobilization in a plaster cast is mandatory after K‑wire osteosynthesis.

CONTRAINDICATIONS

All diaphyseal fractures, if a K-wire is not used as an intramedullary nail. Fractures that can not be correctly reduced or are nonreducible fractures.

SURGICAL TECHNIQUE

After closed or open, as anatomical reduction as possible, one, two, occasionally three K‑wires per fragment are inserted under fluoroscopic control. Care must be taken that the K‑wires optimally capture the fragment to be fixed as well as the main fragment (metaphysis). It must therefore be possible to make a strictly lateral and correct anteroposterior x‑ray by image intensifier. It is important that the C‑arm can be positioned at the appropriate level. Rotating the limb should be minimized, as prior to fixation the previously reduced fragments may shift again, resulting in poor K‑wire fixation. Depending on the morphology of the fracture, size of the fragments and location of the fracture (humerus, forearm, femur or tibia, hand or foot), the K‑wiring technique must be adapted, e.g., mono-laterally crossed, mono-laterally divergent, in an ascending or descending direction, or the most commonly used ascending crossed technique. In most cases, the K‑wires protrude through the sin and the exposed ends are bent. This allows removal without renewed anesthesia in the outpatient setting. K‑wire osteosynthesis is neither a compression osteosynthesis (OS) nor a neutralization OS, but is always an adaptation and fixation of the fragments. Therefore, K‑wire OS always needs additional immobilization using a plaster or prefabricated splint.

POSTOPERATIVE MANAGEMENT

Immobilization in plaster cast for 4-5 weeks, depending on the age; care must be taken to avoid interference between the cast and the skin/K-wires.

RESULTS

With technically and optimally performed fixation and correct indication for K‑wire OS, as well as adequate posttreatment, very good to good results are achieved.

Comparison of Three Different Approaches in Pediatric Gartland Type 3 Supracondylar Humerus Fractures Treated With Cross-Pinning

Introduction

Although closed reduction and percutaneous pinning are the accepted treatment approaches in pediatric humerus supracondylar fractures, the treatment approach in fractures without closed reduction remains unclear. This study compared the results of three different cross-pinning treatment methods.

Materials and methods

A total of 62 patients (1-13 years old) who were operated for Gartland type 3 humerus supracondylar fractures between 2007 and 2016 were evaluated retrospectively. Of the patients evaluated, 24 patients had closed reduction, 25 patients had direct reduction from the medial, and 13 patients had direct reduction from the lateral and cross-pinning. The functional and cosmetic results of the patients were evaluated according to Flynn's criteria. In addition, the Baumann angle, lateral capitellohumeral angle (LCHA), and postoperative complications were compared among groups.

Results

Both functional and cosmetic results and the Bauman and LCHA angles were similar in all three groups. In patients with open reduction, the control duration was significantly longer than that in patients with closed reduction, and this difference was due to a recent increase in the surgeons' preference for closed surgery. Two patients underwent pin site infection and two patients developed nerve palsy. Only the first patient who developed ulnar nerve palsy recovered during follow-up. Secondary surgery was applied to the other patient who developed brachial artery occlusion with ulnar and median nerve paralysis, and they recovered during follow-up. Three patients who underwent open surgery from the medial, along with the two patients who had undergone open surgery, developed pinhole infection. These patients were subsequently recovered with antibiotherapy without further complications. A patient who underwent open lateral surgery developed compartment syndrome and fasciotomy was performed.

Conclusion

Closed reduction and percutaneous pinning are generally accepted approaches in the treatment of pediatric humerus supracondylar type 3 fractures. However, in cases where closed reduction cannot be achieved, pinning with the medial approach and taking the ulnar nerve and medial colon is a reliable method to avoid both ulnar nerve injury and cubitus varus.

A two-stage retrospective analysis to determine the effect of entry point on higher exit of proximal pins in lateral pinning of supracondylar humerus fracture in children

BACKGROUND

Kirschner wire fixation remains to be the mainstream treatment modality in unstable or displaced supracondylar humerus fracture in children, with divergent lateral pins being the most preferred due to their sufficient stability and decreased risk of ulnar nerve injury. However, the entry point at which the proximal lateral pin can be inserted to achieve a more proximal exit and maximum divergence has not been reported. This study retrospectively analyzed the characteristics and factors influencing the entry and exit points of the proximal lateral pins.

METHODS

The study was divided into two stages. In stage one, the entry and exit points of the proximal pins of lateral pinning configuration were analyzed from intra-operative radiographs of children treated for extension-type supracondylar humerus fractures. The coronal and sagittal pin angles formed by the proximal pins were also measured. Using the findings of stage one, we intentionally tried to achieve a more proximal exit with the proximal pins in stage two. Comparisons between groups of patients treated by random and intentional pinnings were done statistically.

RESULTS

In the first stage, 47 (29.2%) of the 161 proximal pins exited above the metaphyseal-diaphyseal junction (MDJ) region. Of these, 85.1% entered from lateral and posterior to the ossific nucleus of the capitellum (ONC). The pin angles averaged 58.4° and 90.5° in the coronal and sagittal planes respectively. In the second stage, 47 (65.3%) proximal pins in the intended group exited above the MDJ region, while only 32 (36%) in the random group exited above the MDJ region.

CONCLUSION

While aiming at the upper border of the distal MDJ during pinning, lateral pins can easily achieve a higher, proximal exit above the MDJ if inserted from lateral and posterior to the ONC and parallel to the humeral shaft in the sagittal plane. Higher exit can also be easily achieved in younger patients and patients fixated with smaller diameter pins.

A comparative biomechanical study on different fixation techniques in the management of transverse metaphyseal-diaphyseal junction fractures of the distal humerus in children

BACKGROUND

Metaphyseal-diaphyseal junction (MDJ) fractures of the distal humerus are problematic to reduce and more susceptible to post-operative complications. This biomechanical study was designed to compare Kirschner wires (KW), lateral external fixation, and elastic stable intramedullary nails (ESIN) in simulated transverse MDJ fractures of various heights.

METHOD

Sagittally oblique, transverse MDJ fractures were created in fourth-generation composite bone models at three levels: high, mid, and low fractures, respectively, and then fixed with either Kirschner wires, lateral external fixation (EF), or ESIN respectively and tested in extension, flexion, valgus, varus, internal, and external rotations.

RESULTS

In the high fractures, ESIN had better overall stiffness than the other techniques. In the mid groups, three crossed pinning (1-medial and 2-lateral pins) had the best overall stiffness, followed by two crossed pinning (1-medial and 1-lateral pins). In the low fractures, three crossed pinning was superior to all other techniques. Two crossed pinning and three -lateral pinning techniques yielded comparable stiffness in the low fracture model.

CONCLUSIONS

From a biomechanical perspective, ESIN provides the best overall stability for fractures located in the upper region of the MDJ, while percutaneous pinning is superior in stabilizing fractures of the lower region. Two lateral and one medial pins make the most stable crossed pinning construct for these fractures.

Operative management of supracondylar humeral fractures in children: Comparison of five fixation methods

BACKGROUND

The best method for stabilising supracondylar humeral fractures (SHFs) in children remains unclear. The objective of this study was to compare the outcomes of five different fixation methods for SHFs in children.

HYPOTHESIS

Differences in intra-operative and short-term post-operative parameters can be demonstrated across different fixation methods for SHFs in children.

PATIENTS AND METHODS

We reviewed the medical files of paediatric patients managed at our centre between 2006 and 2016 for SHF with major displacement (type 3 or 4 in the Lagrange-Rigault classification). Clinical and radiological parameters collected post-operatively and at last follow-up included Baumann's angle, anteversion of the distal humeral epiphysis, and operative time. Over the 11-year study period, 251 patients were included; mean age was 6.4 years and mean follow-up 4.7 months. The five fixation methods used were elastic stable intra-medullary nailing (ESIN, n=16), two pins in an X configuration (n=33), two lateral pins and one medial pin (n=144), two lateral pins (n=33), and three lateral pins (n=25). A minimally invasive 2-cm approach was used to insert the medial pins. Immediate instability of the fixation was considered in patients with an at least 15° deficit in Baumann's angle or anteversion, or with rotational malalignment, on the radiographs taken on day 1. Outcomes were analysed in each of the five internal fixation groups.

RESULTS

Immediate instability showed no significant differences across the five groups. Operative time was significantly shorter with two lateral pins (33min, P=0.046). Time to hardware removal was longer in the ESIN group (54 days, P=0.03). Use of a medial pin was associated with a lower risk of secondary displacement (2.0% vs. 8.6%, P=0.04) but did not affect the risk of nerve injury (4% vs. 3%, P=0.86).

DISCUSSION

This is one of the largest retrospective cohort studies of outcomes according to the fixation technique used to treat SHFs in children. Adding a medial pin through a minimally invasive approach is associated with a longer operative time but limits the risk of secondary displacement without increasing the frequency of iatrogenic nerve injury and improves fracture site stability. Use of a medial pin therefore deserves to be considered in paediatric SHFs.

LEVEL OF EVIDENCE

IV, retrospective cohort study.

Surgical management of delayed irreducible Gartland III supracondylar fractures in children: open reduction and internal fixation versus external fixation

BACKGROUND

Percutaneous pinning has been accepted as the "gold standard" for displaced supracondylar humeral fracture (SHF) in children. However, to secure an anatomic reduction and to reduce the rotated fragment, open reduction is often necessary when there is inadequate stabilization or a satisfactory reduction has failed to be achieved. The study aimed to compare the efficacy of the open reduction and bioabsorbable poly-d,l-lactic acid (PDLLA) pin fixation method with the closed reduction and lateral external fixation method in irreducible delayed Gartland type III SHF in children.

METHODS

In this study, 124 consecutive patients with irreducible delayed Gartland type III SHF were included between 2005 and 2013. Two different surgical methods were performed in patients separately. Group I had 64 patients undergoing bioabsorbable PDLLA pin fixation after open reduction, whereas group II had 60 patients treated by lateral external fixation after closed reduction. The outcome of treatment was evaluated by the Mayo Elbow Performance Score and the criteria of Flynn.

RESULTS

Operation duration was longer in group I than in group II. Scoring of function showed that all patients had satisfactory results in both groups. The cosmetic result was satisfactory in all patients except 1 in group I.

CONCLUSIONS

Both bioabsorbable PDLLA pin fixation and lateral external fixation are reliable, safe treatment alternatives for irreducible delayed SHF. Neither open nor closed reduction is linked to an increased rate of perioperative complications or unsatisfactory functional results.

A comparative study of two percutaneous pinning techniques (lateral vs medial-lateral) for Gartland type III pediatric supracondylar fracture of the humerus

BACKGROUND

The management of displaced supracondylar fracture of the humerus with closed reduction and percutaneous pin fixation is the most widely accepted method of treatment, but controversy continues regarding the pin fixation techniques. A prospective randomized controlled study was undertaken to compare the stability, functional outcome and iatrogenic ulnar nerve injury between lateral pin fixation and medial-lateral pin fixation.

MATERIAL AND METHOD

Sixty-two patients with Gartland type III supracondylar fracture of the humerus were randomized into two groups-lateral pin fixation (n = 31) and medial-lateral pin fixation (n = 31). Primary assessment was performed for major loss of reduction and iatrogenic ulnar nerve injury. Secondary assessment included clinical outcome, elbow range of motion, radiographic measurements, Flynn grade, and complications.

RESULTS

There were two (6.5 %) iatrogenic ulnar nerve injury cases in the medial-lateral entry group and two (6.5 %) cases with mild loss of reduction in the lateral entry group. No major loss of reduction was observed in either of the groups. There was no statistically significant difference in change of Baumann angle, metaphyseal-diaphyseal angle, Flynn grade, carrying angle, and the total elbow range of motion (P < 0.05) between the two groups.

CONCLUSIONS

Lateral pin fixation offers similar functional and radiological outcome and almost equal mechanical stability compared with medial-lateral pinning without the risk of iatrogenic ulnar nerve injury. LEVEL OF EVIDENCE [OCEBM 2011]: Level 2.

Biomechanical comparison of different external fixator configurations for stabilization of supracondylar humerus fractures in children

BACKGROUND

Currently, closed reduction and percutaneous pinning are considered the treatment of choice for displaced supracondylar humerus fractures. However, indications exist for the use of external fixation with Schanz screws. In this in vitro study, we evaluate the biomechanical properties of a new variation for external fixation and compare them to an established construct.

METHODS

Twenty distal cadaver humeri (10 pairs) were allocated to 2 groups. The humeri of the first group were fixed by an external fixator consisting of Schanz screws and an oblique K-wire inserted from the distal radial cortex of the humerus, those of the second group were fixed by a new variation with the oblique K-wire inserted from the distal ulnar cortex of the humerus. Displacement and stiffness in static loading in internal and external rotation, as well as in extension and flexion were evaluated and compared.

FINDINGS

The variation of the external fixator of the second group proved to be statistically significantly superior to the variation of the first group in internal rotation loading (p>0.05). In sagittal loading conditions and external rotation loading, the variations were equally stable (p>0.05). There was no significant effect of the samples' bone density on displacement and stiffness values in any direction of loading.

INTERPRETATION

In cases of pediatric supracondylar humerus fractures when an external fixator is used for osteosynthesis, the insertion of an additional ulnarly inserted anti-rotation K-wire should be preferred to a radially inserted one as it reduces secondary displacement of the distal fragment.

The problem of post-traumatic varization of the distal end of the humerus remaining after the recovery of a supracondylar fracture

We aimed to determine whether the distal end of the humerus had the capacity of spontaneous realignment of the remaining deformity following an inadequate reposition of the supracondylar fracture. The results in 56 children with a supracondylar humerus fracture were analysed. In 45 patients (80%), manual repositioning was performed along with transcutaneous fixation, whereas in 11 patients (20%), only manual repositioning and immobilization in plaster cast was applied. Immobilization was removed and physical therapy was started in all patients on the 21st day following the intervention. Anteroposterior and left-lateral radiography was performed and Baumann's angle was determined. Follow-up radiograph of the elbow of the traumatized and healthy extremity was performed at an interval of 5-15 years (median 9.4). There was no statistically significant difference between the relationship of Baumann's angle of the injured arm measured on the 21st day after the reduction of fragments on the one hand and the carrying angle of the injured and healthy arm measured at the long-term follow-up on the other (t=0.48, P=0.63). Similarly, there was no statistically significant difference between the relationship of Baumann's angle of the injured arm measured at the long-term follow-up and the findings of the carrying angle of both the injured and the healthy arm obtained on the same examination (t=0.78, P=0.44). On the basis of our experience, we conclude that there is no biological capacity to rectify a possible remaining postreduction varus deformity by spontaneous remodelling.

Iatrogenic ulnar nerve injury after pin fixation and after antegrade nailing of supracondylar humeral fractures in children

BACKGROUND AND PURPOSE

Ulnar nerve injury may occur after pinning of supracondylar fractures in children. We describe the outcome and compare the rates of iatrogenic injuries to the ulnar nerve in a consecutive series of displaced supracondylar humeral fractures in children treated with either crossed pinning or antegrade nailing.

METHODS

Medical charts of all children sustaining this fracture treated at our department between 1994 and 2009 were retrospectively reviewed regarding the mode of treatment, demographic data including age and sex, the time until implant removal, the outcome, and the rate of ulnar nerve injuries.

RESULTS

503 children (55% boys) with an average age of 6.5 years sustained a type-II, type-III, or type-IV supracondylar fracture. Of those, 440 children were included in the study. Antegrade nailing was performed in 264 (60%) of the children, and the others were treated with crossed pins. Iatrogenic ulnar nerve injury occurred in 0.4% of the children treated with antegrade nailing and in 15% of the children treated with crossed pinning. After median 3 (1.6-12) years of follow-up, the clinical outcome was good and similar between the 2 groups.

INTERPRETATION

Intramedullary antegrade nailing of displaced supracondylar humeral fractures can be considered an adequate and safe alternative to the widely performed crossed K-wire fixation. The risk of iatrogenic nerve injury after antegrade nailing is small compared to that after crossed pinning.

Composite playground safety measure to correlate the rate of supracondylar humerus fractures with safety: an ecologic study

BACKGROUND

More than 200,000 children are injured at playgrounds in the United States each year. Our goal was to introduce a composite measure of playground safety and use this instrument to correlate the incidence of supracondylar humerus fractures with playground safety in an ecologic study design.

METHODS

We used a novel "overall-safety rating," defined as a composite of 3 previously validated instruments (National Program for Playground Safety School score, surface depth compliance, and the use zone compliance) to measure the overall safety of all playgrounds within a region. The regions were rated from most to least safe based on average playground safety as measured by this new method. The incidence of supracondylar fractures was calculated using Hasbro Children's Hospital Emergency Department data and state of Rhode Island Census data from 1998 to 2006. The incidence was then correlated with playground safety as defined by our composite measure.

RESULTS

Compared with the neighborhood deemed the safest, the least safe district had 4.7 times greater odds of supracondylar humerus fracture. Overall composite safety score of the district was linearly correlated with the injury rate observed in the population at risk (R=0.98; P=0.04).

CONCLUSIONS

Using our novel composite playground safety score, we found that the incidence of supracondylar humerus fractures was increased in districts with playgrounds with lower scores, suggesting that improvements in playground infrastructure may potentially reduce the incidence of supracondylar humerus fractures, and other injuries, in children.

LEVEL OF EVIDENCE

Level IV.

Treatment of displaced supracondylar humeral fractures among children: crossed versus lateral pinning

This retrospective study evaluated different pinning configurations used in the treatment of displaced supracondylar humeral fractures among children, mainly regarding maintenance of fracture reduction and avoidance of complications. The fractures (41 type II and 67 type III) of 108 children (mean age 6.48 years) were treated by closed reduction and percutaneous pinning: 37 with crossed pins, 37 with two lateral pins and 34 with two lateral and one medial pin. Mean follow-up period was 7.4 months. Type III fractures fixed by two lateral pins were found significantly prone to postoperative instability, late complications and need for medial pin fixation. There was a significant relation between either delay to surgery or postoperative instability and occurrence of complications. Final outcome was significantly poorer in type III than in type II fractures. Fixation by two lateral pins only is not recommended for treating type III supracondylar humeral fractures, but could be used initially to fix severely unstable fractures to allow extension of the elbow before inserting a medial pin. Every effort should be made to avoid iatrogenic ulnar nerve injury while inserting the medial pin.

Die elastisch-stabile intramedulläre Nagelung (ESIN) der suprakondylären Humerusfraktur im Kindesalter

Supracondylar fractures are the most common elbow lesions in children. The standard procedure for displaced fractures has up to now been crossed-wire osteosynthesis. A new option is elastic stable intramedullary nailing (ESIN). We retrospectively reviewed the results of all supracondylar fractures that were treated in our department from 2000 to 2005 by the ESIN technique with the aim to provide evidence of advantages and disadvantages of this method. The mean age of the 60 patients included in the study (27 female, 33 male) was 5.9 years (range 1-12 years). Most patients presented with type II fractures (85%), 10% sustained a type III fracture and 5% the most displaced type IV. All patients were treated with the ESIN technique and underwent clinical and radiological follow-up examinations during the next 3-5 months. Average duration to implant removal was 100 days. All patients achieved free range of movement of the affected elbow. No visible malpositions, pseudarthrosis or nerve lesions were observed, in comparison to the conventional surgical technique (crossed-wire osteosynthesis) with up to 19% for these complications. Furthermore, due to the excellent stability of ESIN, the patients do not need a cast and movement is encouraged immediately. Our good experiences encourage us to continue applying the ESIN technique.