Reproducibility of radiographic methods for assessing longitudinal tarsal axes Part 2: Severe cavus or flatfoot study

IntroductionCalcaneal pitch angle and Meary’s angle are commonly used to assess longitudinal foot arches on lateral-view radiographs. The aim of this study was to examine and evaluate the radiographic longitudinal foot arch measurement methods with the best intraobserver and interobserver reliabilities for patients with (1) severe cavus deformity and (2) severe flatfoot deformity.MethodsStanding radiographic images of 22 feet with severe cavus foot deformity and 49 feet with severe flatfoot deformity were obtained to measure the longitudinal axes of the talus, first metatarsal, calcaneus and plantar surface, which were defined using six, five, four and three different methods, respectively, selected from previous reports. Intraobserver and interobserver correlation coefficients were calculated.ResultsThe results are generally consistent with those of Part 1. The best intraobserver and interobserver correlation coefficients for the tarsal axes were obtained using methods involving a line bisecting the angle formed by the lines tangential to the superior and inferior margins of the talus, a line connecting the centre of the first metatarsal head and the midpoint of the visualized base of the first metatarsal, and a line drawn tangential to the inferior surface of the calcaneus. For the plantar axis, a method that used the horizontal plane (as a reference axis) was regarded as the best approach.ConclusionsThe aforementioned methods were considered to be optimal for the radiographic assessment of longitudinal foot arches in patients with severe cavus or flatfoot deformity. This study may contribute to the more accurate assessment of any foot deformity.     

Arthroscopic approach to the spring (calcaneonavicular) ligament

Background

This research studied the safety and efficacy of a new portal to the spring ligament. This portal is located just plantar to the insertion of the posterior tibial tendon and above the fibrous septum between the posterior tibial and the flexor digitorum longus tendons.

Arthroereisis and Pes planovalgus. Tool of the devil or novel implant?

BackgroundThe primary aim of surgical flatfoot management is to correct deformity, provide dynamic support to the medial longitudinal arch and stabilise the hindfoot to allow normal heelstrike and propulsion for toe off. The correction aims to place the calcaneal tuberosity in line with the midsagittal tibia and reduce the talonavicular joint.Materials and MethodsThe standard procedure involves a heel cord lengthening or calf release if indicated. Bony correction involves a varising calcaneal osteotomy. The medial soft tissue correction involves repair of the tibialis posterior tendon and augmentation with a flexor digitorum longus tendon transfer. The arthroereisis implant is inserted into the sinus tarsi via a 2 cm skin incision over a guide wire. The primary role of the arthroereisis is to block the non-physiologic eversion of the subtalar joint by limiting pronation. Thus, the implant acts as an internal arch support, protecting the medial soft tissue repair.ResultsThe senior author has reviewed 84 feet over 7 years of late stage tibialis posterior dysfunction treated in the above technique. No infections were recorded and 30% of implants were removed after 6 months for subtalar discomfort. Less favourable outcome was associated with over- or undersizing of the implant.ConclusionArthroereisis allows for a good correction adult onset pes planovalgus. It provides an additional tool in the armamentarium of the foot and ankle surgeon for the management of a difficult condition     

Combined weightbearing CT and MRI assessment of flexible progressive collapsing foot deformity

BackgroundThe objective of this study was to evaluate the correlation between Weightbearing CT (WBCT) markers of pronounced peritalar subluxation (PTS) and MRI findings of soft tissue insufficiency in patients with flexible Progressive Collapsing Foot Deformity (PCFD). We hypothesized that significant correlation would be found.MethodsRetrospective comparative study with 54 flexible PCFD patients. WBCT and MRI variables deformity severity were evaluated, including markers of pronounced PTS, as well as soft tissue degeneration. A multiple regression analysis and partition prediction models were used to evaluate the relationship between bone alignment and soft tissue injury. P-values of less than .05 were considered significant.ResultsDegeneration of the posterior tibial tendon was significantly associated with sinus tarsi impingement (p = .04). Spring ligament degeneration correlated to subtalar joint subluxation (p = .04). Talocalcaneal interosseous ligament involvement was the only one to significantly correlate to the presence of subfibular impingement (p = .02).ConclusionOur results demonstrated that WBCT markers of pronounced deformity and PTS were significantly correlated to MRI involvement of the PTT and other important restraints such as the spring and talocalcaneal interosseus ligaments.LEVEL OF EVIDENCE: Level III, Retrospective comparative study.     

Approach and treatment of the adult acquired flatfoot deformity

Adult acquired flatfoot deformity (AAFD), embraces a wide spectrum of deformities. AAFD is a complex pathology consisting both of posterior tibial tendon insufficiency and failure of the capsular and ligamentous structures of the foot. Each patient presents with characteristic deformities across the involved joints, requiring individualized treatment. Early stages may respond well to aggressive conservative management, yet more severe AAFD necessitates prompt surgical therapy to halt the progression of the disease to stages requiring more complex procedures. We present the most current diagnostic and therapeutic approaches to AAFD, based on the most pertinent literature and our own experience and investigations.