The results of the present study demonstrate that the majority of cubitus varus deformities can be treated nonsurgically for young children within one year after the initial injury using the FBPT technique.
Cubitus varus deformity is generally due to medial displacement or insufficient reduction of the distal humeral fragment after supracondylar humerus fractures, which remains a challenge for orthopedic surgeons [16]. Although many authors recommended early correction of pediatric cubitus varus deformity, the optimal timing has not yet been well-established in the literature [17,18,19,20,21]. Meanwhile, the ideal technique for cubitus varus correction remained controversial. Various osteotomies have been described and complications associated with these procedures include pin-tract infection, overcorrection or under-correction, prominence of the lateral condyle, and iatrogenic neurological injury [9, 22]. To the best of the authors’ knowledge, the spontaneous correction of the cubitus varus is highly unlikely to happen with time in growing children. Development in surgical techniques and orthopedic implants have resulted in a significant increase in the surgical treatment of cubitus varus. However, most of the patients and their parents are willing to obtain nonsurgical correction of cubitus varus for cosmetic reasons [23].
The Hueter-Volkmann law, which states that excessive pressure to a part of the joint leads to local growth retardation and reduced pressure to a part of the joint leads to local growth acceleration, explains why the FBPT technique can be successfully applied for children with cubitus varus [24]. When the band from the back was tightened, the brace can produce valgus stress on the extended elbow joint. After wearing 23 h a day for the first three months, it could provide constant compression on the lateral epiphysis of the affected elbow joint and then lead to growth retardation. For the medial epiphysis of the affected elbow joint, decreased stress leads to increased growth. Meanwhile, physical therapy was needed in all the patients in our series, which can enhance the effect of correction and avoid elbow joint stiffness or amyotrophy. Due to the slow and long-term treatment process, the patients need to return to the hospital regularly for observation and adjust the wearing time of the brace with high adherence.
In the present study, fourteen patients (77.8%) achieved excellent results while three patients (16.7%) achieved good results. On the other hand, the results of the meta-analysis for surgical treatment estimated an 87.8% overall rate of good to excellent results throughout the literature [20]. Therefore, the FBPT technique for cubitus varus conservative treatment achieves a higher rate of satisfactory results. The HEW angle was significantly improved from mean -23.2° (range, -38° to -12°) pre-treatment to mean 8.8° (range, -10° to + 15°) post-treatment. The advantages of FBPT technique include better correction and cosmetic outcome, no further surgery for implant removal, no complications such as scarring or lateral condyle prominence.
The limitations of this retrospective study include the small number of cases with a short follow-up period. Meanwhile, no comparison was made with other established techniques. This study is a single group, pre-post test design with no control group. Therefore, we will plan to conduct multi-center prospective study, involving a randomised controlled trial design to increase the internal validity of these results in the next step. Second, post treatment data including one month, three months, six months, 12 months and every year thereafter assessments are insufficient. Besides, cubitus varus is a 3D-deformity and therefore sagittal plane results via the FBPT should be included. Despite these limitations, this technique could provide a simple and reproducible therapeutic procedure for the correction of cubitus varus deformity in the clinic.