Background Context. The presence of special, rare and various forms which we can encounter when treating supracondylar humeral fractures (SHF) in children, call into question what therapeutic methods can be used to increase the effectiveness of the treatment applied. The aim of this paper is to present the results obtained by using double cross-fixation, "in double X", by closed reduction and percutaneous pinning (CRPP) or open reduction and internal fixation (ORIF) in treating rare and particular forms. Comments and opinions on "double X" method and other cross or side configurations are presented. Patient Sample. All patients with rare and particular forms presented in this article, were operated during 2001–2020 in state and private hospitals. Fixation in "double X" was used either by CRPP and ORIF. The epitrochlear approach (EA) was performed in cases where stability by CRPP could not be ensured or when there were clear signs of ulnar nerve damage. The minimal medial-approach (mMA) highlights the epitrochlea and the fracture of the medial pylon; it has the role of anatomically reducing the medial pylon, thinner and very unstable in rare and particular forms. During 1982–2020 we consulted, treated and evaluated patients with SHF to whom all known treatment methods were applied: orthopedic reduction and immobilization in plaster cast, CRPP, ORIF, minimal-open reduction and internal fixation (mORIF) by mMA and external fixator. Internal fixation was done by the techniques of Judet, San Antonio, San Diego, Dorgan, in “X” and “double X”. In 2001, I introduced "double X" fixation to better stabilize anatomical reductions that showed signs of instability during intraoperative verification. All indications given in the study protocol have been made in accordance with the regulations mentioned in the experimental program. Results. All SHFs operated by CRPP and ORIF by “double X” were cured and satisfactory and good results were obtained in the neglected types operated between 14 and 60 days and good and excellent results were obtained in the rare forms. Conclusions. “Double X” fixation gives the best stabilization and postoperatively there is no need for immobilization in a plaster cast. Recovery may begin the day after surgery.

Background Context. The presence of special, rare and various forms which we can encounter when treating supracondylar humeral fractures (SHF) in children, call into question what therapeutic methods can be used to increase the effectiveness of the treatment applied. The aim of this paper is to present the results obtained by using double cross-fixation, "in double X", by closed reduction and percutaneous pinning (CRPP) or open reduction and internal fixation (ORIF) in treating rare and particular forms. Comments and opinions on "double X" method and other cross or side configurations are presented. Patient Sample. All patients with rare and particular forms presented in this article, were operated during 2001-2020 in state and private hospitals. Fixation in "double X" was used either by CRPP and ORIF. The epitrochlear approach (EA) was performed in cases where stability by CRPP could not be ensured or when there were clear signs of ulnar nerve damage. The minimal medial-approach (mMA) highlights the epitrochlea and the fracture of the medial pylon; it has the role of anatomically reducing the medial pylon, thinner and very unstable in rare and particular forms. During 1982-2020 we consulted, treated and evaluated patients with SHF to whom all known treatment methods were applied: orthopedic reduction and immobilization in plaster cast, CRPP, ORIF, minimal-open reduction and internal fixation (mORIF) by mMA and external fixator. Internal fixation was done by the techniques of Judet, San Antonio, San Diego, Dorgan, in “X” and “double X”. In 2001, I introduced "double X" fixation to better stabilize anatomical reductions that showed signs of instability during intraoperative verification. All indications given in the study protocol have been made in accordance with the regulations mentioned in the experimental program. Results. All SHFs operated by CRPP and ORIF by “double X” were cured and satisfactory and good results were obtained in the neglected types operated between 14 and 60 days and good and excellent results were obtained in the rare forms. Conclusions. “Double X” fixation gives the best stabilization and postoperatively there is no need for immobilization in a plaster cast. Recovery may begin the day after surgery. Keywords: supracondylar fractures, child elbow pathology, cross-fixation, lateral fixation, healing and recovery after 30-45 days.