Peroneus brevis as source of instability in Jones fracture fixation

Abstract

Purpose Intramedullary screw fixation is currently considered the gold standard treatment for Jones fractures in the athlete. Besides biological factors (i.e., poor vascularization), mechanical instability induced by the pull of the peroneus brevis tendon (PBT) contributes to deficient Jones fracture healing. This biomechanical study aimed to simulate loads induced by the PBT at the fifth metatarsal and to compare the stability of two intramedullary screw constructs in a Jones fracture fixation model. Methods Jones fractures were created in 24 human paired specimens, and fixation was achieved with either a solid Jones fracture specific screw (JFXS) (Jones Screw; Arthrex Inc., Naples FL, USA) or a cannulated headless compression screw (HCS) (HCS; DePuySynthes, Solothurn, Switzerland). The PBT was fixed to a mechanical load frame by the use of a cryoclamp. Constructs were loaded in tension for 1000 cycles, followed by an ultimate load test. Construct failure was defined by exceeding 10°of dorsal angulation. Results Preliminary failure occurred more often in HCS constructs (33%) compared to JFXS constructs (0%) (P = 0.044). Mean tensile load to failure reached 123.8 ± 91.4 N in the JFXS group and 91.5 ± 62.2 N in the HCS group (P = 0.337). The mean slope of the load-displacement curve was 24.2 ± 10.4 N/mm for JFXS constructs and 24.7 ± 5.5 N/mm for HCS constructs, respectively (P = 0.887). Conclusion This is the first study evaluating the effect of PBT pull on the mechanical stability of Jones fracture fixation. Higher preliminary failure rates of HCS were found under cyclic loading conditions compared to JFXS.

Biomechanical Comparison of Cannulated Screw Osteosynthesis With Tension-Band Wiring for Proximal Fractures of the Fifth Metatarsal (Jones Fracture)

“…For the test, the force was introduced via a dorsally directed vector, the existing rotational impulses through the tendon of the m. peroneus brevis were under-estimated (4,20). The value of rotational forces in Jones fractures has not been clearly proven, as the natural joint surfaces and surrounding soft tissue can only allow slight rotational movements.…”

“…Poor blood supply as shown by Smith et al ( 3) is a reason for prolonged healing time in non-operative treatment of this fracture type leading to delayed union or non-union. Furthermore, activation of the peroneal tendons inserting proximally to the fracture site during gait contribute to dislocation of Jones fractures (4). Therefore, surgical treatment was recommended to avoid this complication and the associated more complicated course of treatment.…”

Fractures of the Base of the Fifth Metatarsal Bone

“…Nevertheless, variable-pitch headless compression screws, although they generate 30% less compression 150 and have inferior fatigue strength 144 than partially threaded constant-pitch screws, led to excellent outcomes in a study of 60 Japanese athletes, with a 97% union rate and no refractures 139 . Indication-specific screws have improved biomechanical properties over traditional screws 144,151,152 , with less adverse events demonstrated in 1 clinical study 141 .…”

Biomechanical comparisons of F.E.R.I. techniques with different type of intramedullary screws fixation for Jones fractures

“…Therefore, intramedullary fixation with partially threaded cannulated screws has traditionally been the implant of choice for Jones fractures, allowing athletes early weight-bearing and return to sport. However, conventional cannulated screw fixation, especially with small diameters, may inherently struggle to resist loads from peroneus brevis pulling ( Willegger et al, 2020b ), resulting in failure rates of 5%–7.3% ( Wright et al, 2000 ; Granata et al, 2015 ). Headless Herbert-style compression screws and other fixation techniques aimed at achieving superior initial stability have been introduced to reduce failure rates ( Lee et al, 2011 ; Lam et al, 2021 ).…”