The Effectiveness of Tripod Index in Defining Hallux Valgus Deformity: A Retrospective Study

Abstract

Aim: The aim of this study is to investigate the effectiveness and reliability of the Tripod Index (TI) in defining hallux valgus (HV) deformity and accompanying deformities and evaluating the treatment outcome. Material and Methods: Fifty and fifty two patients were included to the study who underwent Chevron (group 1) and proximal dome (group 2) osteotomy, respectively. Preoperative and postoperative hallux valgus angle (HVA), intermetatarsal angle (IMA), Meary angle (MA), talar declination angle (TDA), calcaneal tilt angle (CIA), talar head opening (THU) and TI were measured. Then, the relationship between TI and other angular variables was evaluated. Results: There was no significant difference between the mean age, body mass index (BMI), side and gender of the patients in both groups. The mean values of HVA and IMA differed between two groups both pre- and postoperatively. The preoperative TDA, THU and MA values were significantly higher in group 2. The preoperative mean CIA was significantly higher in group 1. The preoperative value of the TI was significantly higher in group 2. There was a significant decrease in all angular parameters in group 2 postoperatively. There was a significant decrease in mean HVA, IMA and TI postoperatively in group 1. There was strong correlation between TI and IMA, THU, CIA, TDA and MA, and moderate correlation with HVA in both groups. Conclusion: TI can provide partial data on the transverse and sagittal plane deformity of the first metatarsal deformity in HV with a single radiograph. Additionally, it can be a guiding measurement in evaluating the need for calcaneal shift osteotomy in pes planovalgus deformities accompanying HV. However, it is insufficient to define complex HV deformity alone.

Keywords

• hallux valgus
• osteotomy
• metatarsal deformity

Halluks Valgus Deformitesinin Tanımlanmasında Tripod İndeksin Etkinliği : Retrospektif Bir Çalışma

Abstract

Amaç: Bu çalışmada, Tripod Index'in (TI) halluks valgus (HV) deformitesini tanımlamada ve tedavi sonucunu değerlendirmede etkinliğini ve güvenilirliğini araştırmayı amaçladık. Gereç ve Yöntemler: Bu çalışma, sırasıyla Chevron (grup 1) ve proksimal kubbe (grup 2) osteotomisi yapılan 50 ve 52 hastayı içermektedir. Halluks valgus açısı (HVA), intermetatarsal açı (İMA), Meary açısı (MA), talar eğim açısı (TEA), kalkaneal eğim açısı (KEA), talar baş örtünme (TBÖ) ve TI değerleri ameliyat öncesi ve sonrası ölçüldü. TI ile diğer açısal değişkenler arasındaki ilişki değerlendirildi. Bulgular: Her iki gruptaki hastaların ortalama yaş, vücut kitle endeksi, taraf ve cinsiyet dağılımları arasında anlamlı bir fark yoktu. Ortalama HVA ve İMA değerleri iki grup arasında ameliyat öncesi ve sonrası farklılık saptandı. TEA, TBÖ ve MA değerleri incelendiğinde grup 2'nin preoperatif ortalama değeri anlamlı olarak yüksekti. Preoperatif ortalama KEA grup 1'de anlamlı olarak daha yüksekti. Preoperatif ortalama TI değerleri grup 2'de anlamlı derecede yüksekti. Grup 2'de postoperatif tüm açısal parametrelerde anlamlı azalma oldu. Grup 1'de ortalama HVA, İMA ve TI'de postoperatif olarak anlamlı düşüş vardı. Her iki grupta da TI ile İMA, TBÖ, KEA, TEA ve MA arasında güçlü, HVA ile orta derecede korelasyon vardı. Sonuç: TI, HV’de birinci metatarsın transvers ve sagital düzlem deformitesi hakkında tek bir radyografi ile kısmi veri sağlayabilir. Ayrıca, halluks valgusa eşlik eden pes planovalgus deformitelerinde kalkaneal kaydırma osteotomisi ihtiyacının değerlendirilmesinde yol gösterici bir ölçüm olabilir. Ancak kompleks HV deformitesini tek başına tanımlamakta yetersizdir.

Keywords

• halluks valgus
• osteotomi
• metatarsal deformite

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