Abstract

Background: Heel pain associated with a disease process of the medial band of the plantar fascia, Plantar Fasciopathy (PF), is a frequently complaint among patients presenting to foot care specialists. Excessive foot pronation, subtalar joint instability, has been cited as a leading biomechanical factor in the development of PF. The frequency of association between excessive hind foot motion and chronic heel pain has not been studied. The purpose of this retrospective study was to evaluate the occurrence of subtalar joint instability, as evidenced by radiographic angular measurements, in patients diagnosed and surgically treated for recalcitrant PF.

Method: Pre-operative relaxed stance weight bearing radiographs for one-hundred eight patients diagnosed with recalcitrant PF, who had partial or full, of the plantar fasciotomy, were retrospectively and independently reviewed. Subtalar joint instability was measured objectively via the Talar second Metatarsal angle (T2M) on the dorsoplantar radiograph for transverse plane alignment and the Talar Declination angle (TD) on the lateral radiograph for sagittal plane alignment.

Results: 93.52% (101 feet) had at least one angle (T2M or TD) greater than normal accepted values. T2M angles were greater than the normal values 79.63% (86 feet) of the feet examined. With respect to TD angles, 75.93% (82 feet) showed greater than normal values. 17.59% (19) of the feet showed only higher T2M angles, indicating transverse plane dominance, while 13.89% (15 feet) indicated only higher TD angles, indicating sagittal plane dominance. 62.04% (67 feet) had both higher T2M and TD angles.

Conclusion: The data from this study showed a statically significant number of patients with recalcitrant heel pain also exhibited excessive subtalar joint pronation. This could explain the rational for a subset of patients who are unresponsive to typical treatments aimed at healing the diseased fascial tissue, without addressing the co-deformity of subtalar joint instability. Patients who develop recalcitrant PF should be evaluated for subtalar joint instability and options to realign and stabilize the subtalar joint should be incorporated as part of the treatment protocol.

Keywords: Plantar fasciitis; Plantar fasciopathy; Plantar fasciosis; Subtalar joint instability; Hyperpronation; Peri-talar subluxation talotarsal joint displacement