Association of posterior tibial tendon injury with spring ligament injury,sinus tarsi abnormality, and plantar fasciitis on MR imaging

OBJECTIVE. The purpose of this study was to investigate the frequency of ab normalities of, the spring Ligament, sinus tarsi. and plantar fascia reveal ed on MR imaging in a group of patients with advanced injury of the posteri or tibial tendon. MATERIALS AND METHODS. MR images from 25 patients with advanced posterior t ibial tendon injury were retrospectively examined for spring ligament. sinu s tarsi. and plantar fascia abnormalities. These images were randomly compa red with those obtained from 25 control patients with normal-appearing post erior tibial tendons. RESULTS. The spring ligament was abnormal in 23 (92%) of 25 patients with a posterior tibial tendon injury and seven (28%) of 25 patients with a norma l posterior tibial tendon (p < 0.0001). The sinus tarsi was abnormal in 18 (72%) of 25 patients with posterior tibial tendon injury and nine (36%) of 25 patients with a normal posterior tibial tendon (p < 0.0131). The plantar fascia was al,normal in seven (32%) of 22 patients with posterior tibial t endon injury and two (9%) of 22 patients with a normal posterior tibial ten don (p < 0.0768). Two or more associated abnormalities were present in 20 ( 80%) of 25 patients with posterior tibial tendon injury and four (16%) of 2 5 patients with a normal posterior tibial tendon (p < 0.0001). CONCLUSION. Advanced posterior tibial tendon injury has a high association with spring ligament and sinus tarsi abnormalities on MR imaging. There was : a Low association between advanced posterior tibial tendon injury and pla ntar fascia abnormality. Patients with posterior tibial tendon injury often have abnormalities of two or more associated structures.