Loss of Pin Fixation in Displaced Supracondylar Humeral Fractures in Children: Causes and Prevention

Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Wood Building, 2nd Floor, 34th and Civic Center Boulevard, Philadelphia, PA 19104, USA.
The Journal of Bone and Joint Surgery (Impact Factor: 5.28). 04/2007; 89(4):713-7. DOI: 10.2106/JBJS.F.00076
Source: PubMed


Although the results are generally good following pin fixation of supracondylar humeral fractures in children, occasionally there is postoperative displacement. The purposes of the present study were to identify the causes leading to loss of fixation after pin fixation and to present methods for prevention.
We evaluated 322 displaced supracondylar humeral fractures that had been treated with percutaneous pin fixation. We examined fracture classification, pin configuration, intraoperative alignment after fixation, change in alignment after fixation, details of additional procedures, and final radiographic and clinical outcomes.
Adequate radiographs were available for 279 of the 322 fractures. Eight (2.9%) of the 279 fractures were associated with postoperative loss of fixation; all eight were Gartland type-III fractures. Seven of these eight fractures initially had been treated with two lateral-entry pins, and one had been treated with two crossed pins. In patients with Gartland type-III fractures, loss of fixation was successfully avoided more often when three pins were used (with fixation being maintained in thirty-seven of thirty-seven patients) as opposed to when two lateral-entry pins were used (with fixation being maintained in thirty-five of forty-two patients) (p = 0.01). In all cases, loss of fixation was due to technical errors that were identifiable on the intraoperative fluoroscopic images and that could have been prevented with proper technique. We identified three types of pin-fixation errors: (1) failure to engage both fragments with two pins or more, (2) failure to achieve bicortical fixation with two pins or more, and (3) failure to achieve adequate pin separation (>2 mm) at the fracture site.
Postoperative displacement following pin fixation of supracondylar humeral fractures in children is uncommon. In the present series, loss of fixation was most likely to occur when Gartland type-III fractures were treated with two lateral-entry pins. There were no failures when three pins were used. In all cases of failure, there were identifiable technical errors in pin placement.
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    • "This is biomechanically inferior as it creates a single hold in the proximal fragment and is thus responsible for loss of reduction. Technical errors have been found contributory to loss of reduction in other series as well.56911 Sankar et al. found three technical errors similar to those seen in our series.6 "
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    ABSTRACT: Loss of reduction following closed or open reduction of displaced supracondylar fractures of the humerus in children varies widely and is considered dependent on stability of the fracture pattern, Gartland type, number and configuration of pins for fixation, technical errors, adequacy of initial reduction, and timing of the surgery. This study was aimed to evaluate the factors responsible for failure of reduction in operated pediatric supracondylar fracture humerus. We retrospectively assessed loss of reduction by evaluating changes in Baumann's angle, change in lateral rotation percentage, and anterior humeral line in 77 consecutive children who were treated with multiple Kirschner wire fixation and were available for followup. The intraoperative radiographs were compared with those taken immediately after surgery and 3 weeks postoperatively. Multivariate logistic regression analysis was performed by STATA 10. Reduction was lost in 18.2% of the patients. Technical errors were significantly higher in those who lost reduction (P = 0.001; Odds Ratio: 57.63). Lateral pins had a significantly higher risk of losing reduction than cross pins (P = 0.029; Odds Ratio: 7.73). Other factors including stability of fracture configuration were not significantly different in the two groups. The stability of fracture fixation in supracondylar fractures in children is dependent on a technically good pinning. Cross pinning provides a more stable fixation than lateral entry pins. Fracture pattern and accuracy of reduction were not important factors in determining the stability of fixation.
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    ABSTRACT: Le fratture sovracondiloidee di omero sono le più comuni lesioni del gomito in età pediatrica. Le fratture di tipo I secondo Garland sono trattate incruentemente, mentre quelle di tipo II e III richiedono trattamento chirurgico. Le fratture di tipo II sono trattate con riduzione a cielo chiuso e fissazione. Le fratture tipo III possono richiedere la riduzione a cielo aperto. Dal 2001 al 2011 abbiamo trattato chirurgicamente 44 pazienti, 8 con fratture tipo II e 35 con fratture tipo III. Tutti i pazienti sono stati stabilizzati con 2 fili di Kirschner. Le fratture di tipo II sono state ridotte a cielo chiuso, quelle di tipo III a cielo aperto. Sono stati riscontrati: un caso di disturbi a carico del nervo ulnare e un caso a carico del nervo radiale, regrediti spontaneamente, un caso di lieve deformità in varo e uno in valgo. In nessuna evenienza è stato necessario un nuovo intervento chirurgico.
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