Biomechanical analysis of tension band wiring (TBW) of transverse fractures of patella

Abstract

PurposeTension band wiring is commonly used for fixation of simple transverse fractures. The popular configuration is parallel Kirschner wires (K-wires) and a stainless steel wire loop placed in a vertically oriented figure-of-8.MethodsWe used a wooden model of a patella with a midway transverse fracture and compared four different types of fixation. The first construct had a vertical figure-of-8 with one twist of wire. The second contained a vertical figure-of-8 with two twists of wire. The third was a vertical figure-of-8 with two twists of wire placed at adjacent corners while the last one had a horizontal figure-of-8 with two twists of wire placed at adjacent corners. Interfragmentary compression at the point of wire breakage was measured for each construct as well as permanent displacement on cyclic loading.ResultsPlacement of the figure-of-eight in a horizontal orientation with two wire twists at the corner improved interfragmentary compression by 63% (p < 0.05, Tukey post hoc test). On cyclic loading, all the constructs with vertical figure-of-eight but none with a horizontal construct failed (p = 0.01; Fisher's exact test). Permanent fracture displacement after cyclic loading was 67% lower with horizontal figure-of-eight constructs (p < 0.05; t test).ConclusionPlacing wire twists at the corner and a horizontal placement of figure-of-8 improves stability of the construct.

Influence of wire configuration on resistance to fragment distraction of tension bands placed in a greater trochanteric osteotomy model

“…The femur model and setup for testing the TB configurations in this study were designed to be anatomically correct and simulate a physiological loading direction on the greater trochanter during gait while also isolating the performance of the wiring portion of the construct and removing the contributions of K‐wire stabilization and bone stiffness, as present in cadaver studies. In previous studies in which bone models have been used, the materials used to simulate bone were more compliant, such as Delrin bar models or wooden patella models, introducing compliance within the testing structure that could potentially confound the mechanical property measurements of the constructs alone. Anatomical loading has been used similarly to our study in some previous studies, but, in those studies, K‐wires were inserted across the fracture gap for stability and thus did not isolate the performance of the wiring configurations under loading .…”

“…In previous studies in which bone models have been used, the materials used to simulate bone were more compliant, such as Delrin bar models or wooden patella models, introducing compliance within the testing structure that could potentially confound the mechanical property measurements of the constructs alone. Anatomical loading has been used similarly to our study in some previous studies, but, in those studies, K‐wires were inserted across the fracture gap for stability and thus did not isolate the performance of the wiring configurations under loading . Other researchers isolated the wiring configurations but did not perform anatomical loading .…”

“…Previous TB studies have incorporated a variety of configurations in the presence of K‐wires with or without other securing devices, such as lag screws or bone staples, to determine the most effective (ie, strongest, most stable) wire construct . However, the load resistance of the wire portion alone without the confounding influence of K‐wire stabilization has not been evaluated and may inform improved TB wire designs to mitigate the persisting complications with TB fixation.…”

Quality of life of patients with various variants of osteosynthesis of patellar fractures.

“…қОрЫтЫНДЫ Әдебиет мәліметтері бойынша тізе үсті сүйегі сынығы [9,10] емнің алғашқы кезеңдерінде айтарлықтай қиындықтар туғызбайды. Күрделі емес сынықтар кезінде сынық бөліктерін орнына келтіріу оңай, ал оларды қазіргі таңда қолданылатын әдістер арқылы фиксациялау жиі жағдайда сынық бөлімдерінің екіншілік орнынан жылжуына әкеп соғады [11]. Орнынан жылжу сагиттальді жазықтықта немесе сынық бөлімінің айланып кетуі түрінде болып, ол өз кезегінде тізе үсті сүйегі ішкі бетінде «баспалдақ» түзілуіне әкеледі.…”

Cannulated Screws and Braided Polyester Tension Band as an Alternative for Fixation of Transverse Patella Fracture: A Finite Element Analysis Study

“…18,31,32,34,36 Another variation includes horizontal orientation of the figure-of-eight loop which was proven to provide better fixation stability, compared to traditional vertically oriented technique. 11,[44][45][46] On the basis of the available evidence, it seems fair to suggest that combining the cannulated screws with horizontal braided polyester loop should provide a strong tension band construct. To our knowledge, there was only one literature focusing on this configuration, which was a biomechanical study in 13 cadavers.…”