The Effect of Patellar Height on Load Distribution in the Knee: Is It a Risk Factor for Meniscal Tears?

Abstract

Objective: The aim of this study was to determine the frequency of patella alta in patients with arthroscopically confirmed meniscal tears and to evaluate the relationship between patellar height and the side, anatomical location, and type of meniscal tears. Materials and Methods: A total of 152 patients (84 males, 68 females; mean age 36.2 years) who underwent knee arthroscopy were included in this study. Preoperative lateral knee radiographs were evaluated to calculate the Insall-Salvati Index (ISI) and Caton-Deschamps Index (CDI). An ISI > 1.2 was defined as Patella Alta. Meniscal tear side (medial, lateral, bilateral), anatomical zone (anterior horn, body, posterior horn), and tear pattern were documented from arthroscopy reports and correlated with radiological measurements. Results: Arthroscopic evaluation revealed medial meniscal tears in 84.2% (n = 128), lateral meniscal tears in 9.2% (n = 14), and bilateral tears in 6.6% (n = 10) of the patients. The overall prevalence of patella alta was 42.1% (n = 64). Patients with patella alta demonstrated a significantly higher proportion of medial meniscal tears (87.5%) compared to those with normal patellar height (p = 0.042). Anatomical location analysis showed that tears in the patella alta group were predominantly localized in the posterior horn (73.4%, n = 47) compared to the normal patella group (p < 0.001). Furthermore, complex and flap tear patterns were significantly more frequent in the high patella group (p = 0.016). Conclusion: Patella alta is present in a substantial proportion (42.1%) of patients undergoing arthroscopy for meniscal tears. High patellar height exhibits a strong clinical and anatomical association with medial meniscal posterior horn tears and complex tear patterns. Recognizing this biomechanical influence of the extensor mechanism is crucial when planning surgical repair and rehabilitation strategies.

Keywords

• Patella alta
• Patellar height
• Insall–Salvati index
• Meniscal tear
• Knee arthroscopy
• Posterior horn

PATELLA YÜKSEKLİĞİNİN DİZE YÜK DAĞILIMINA ETKİSİ: MENİSKÜS YIRTIKLARI İÇİN RİSK FAKTÖRÜ MÜ?

Abstract

Amaç: Bu çalışmanın amacı, artroskopik olarak menisküs yırtığı tanısı kesinleştirilmiş olgularda patella yüksekliği (patella alta) sıklığını belirlemek ve patella yüksekliğinin menisküs yırtıklarının tarafı, anatomik yerleşimi ve tipi ile olan ilişkisini incelemektir. Gereç ve Yöntem: Çalışmaya artroskopik cerrahi uygulanan 152 hasta (84 erkek, 68 kadın; ortalama yaş 36.2 yıl) dahil edildi. Hastaların ameliyat öncesi yan diz radyografileri üzerinden Insall-Salvati İndeksi (ISI) ve Caton-Deschamps İndeksi (CDI) hesaplandı. ISI > 1.2 değeri Patella Alta olarak kabul edildi. Artroskopi kayıtlarından menisküs yırtığının tarafı (medial, lateral, bilateral), anatomik bölgesi (ön, gövde, arka boynuz) ve yırtık tipleri kaydedilerek radyolojik verilerle karşılaştırıldı. Bulgular: Artroskopik değerlendirmede hastaların %84.2’sinde (n = 128) medial, %9.2’sinde (n = 14) lateral ve %6.6’sında (n = 10) bilateral menisküs yırtığı saptandı. Tüm grupta patella alta oranı %42.1 (n = 64) olarak bulundu. Patella alta saptanan olgularda medial menisküs yırtığı oranı (%87.5), normal patella grubuna göre anlamlı derecede yüksek izlendi (p = 0.042). Anatomik yerleşim analizinde, Patella alta varlığında yırtıkların %73.4 (n = 47) oranında belirgin şekilde arka boynuzda (posterior horn) yoğunlaştığı görüldü (p < 0.001). Ayrıca yüksek patella grubunda kompleks ve flep tipi yırtık sıklığının anlamlı düzeyde yüksek olduğu belirlendi (p = 0.016). Tartışma: Artroskopi yapılan menisküs yırtıklı olgularda yüksek patella (patella alta) sıklığı %42.1 gibi yüksek bir orandadır. Patella yüksekliği, özellikle medial menisküs arka boynuz yırtıkları ve kompleks yırtık tipleri ile güçlü bir klinik ve anatomik ilişki göstermektedir. Cerrahi ve rehabilitasyon planlamasında diz ekstansör mekanizmasının bu biyomekanik etkisinin göz önünde bulundurulması önem taşımaktadır.

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