STUDY DESIGN: Clinical measurement. OBJECTIVE: To determine the validity and reliability of measures obtained using a custom-made device for assessing ankle dorsiflexion motion and stiffness. BACKGROUND: Limited dorsiflexion has been implicated in the evolution of foot pain in a number of clinical populations. Assessment of ankle dorsiflexion range of motion (ROM) is, therefore, commonly performed as part of a foot and ankle examination. Conventional goniometric assessment methods have demonstrated limited intertester reliability, while alternative methods of measurements are generally more difficult to use. The Iowa ankle range of motion (IAROM) device was designed in an attempt to develop a simple, clinically relevant, and time- and cost-effective tool to measure ankle dorsiflexion range of motion and stiffness. METHODS: Validity and intertester reliability of dorsiflexion range-of-motion measures using the IAROM device were assessed at 10, 15, 20, and 25 Nm of passively applied dorsiflexion torque, with both the knee extended and flexed approximately 20°. Stiffness (change in torque/change in dorsiflexion angle) values were determined using the angular change obtained between the 15- and 25-Nm torque levels. Convergent validity (n = 12) was assessed through comparison of ankle dorsiflexion angles measured simultaneously with the IAROM device and an optoelectronic motion analysis system. Intertester reliability (n = 17) was assessed by 2 testers who took measurements within the same day. RESULTS: Validity testing demonstrated excellent agreement (intraclass correlation coefficient [ICC] values ranging from 0.95 to 0.98). Reliability testing demonstrated good to excellent intertester agreement (ICC values ranging from 0.90 to 0.95). The ICCs for ankle joint dorsiflexion stiffness were .71 and .85 for the knee in an extended and flexed position, respectively. CONCLUSION: The IAROM device provides valid and reliable measurement of ankle dorsiflexion ROM. The IAROM device also allows calculation of stiffness by measuring ROM at multiple torque levels, although the reliability of the measurement is not optimal.

J Orthop Sports Phys Ther 2011;41(4):274-280. doi:10.2519/jospt.2011.3397

KEY WORDS: IAROM, plantar flexors, stiffness, talocrural joint

The surgical treatment of painful, end-stage ankle arthritis includes ankle arthrodesis and total ankle replacement.In the past decade, total ankle replacement has become a viable alternative to ankle arthrodesis. Modern implant designs either involve a syndesmosis fusion and resurfacing of the medial and lateral recesses of the ankle joint or the use of a 3-component, mobile bearing implant. In limited clinical series, the early results of both these prosthetic design approaches are encouraging. In selected patients, ankle arthroplasty is an effective approach to relieving pain and improving function. The purposes of this paper are to review the clinical results from total ankle replacement and ankle arthrodesis; discuss indications, contraindications, design features, postoperative rehabilitation, and initial results for the major current total ankle designs; and present concepts for future total ankle development. In particular, this article explores the advantages and concerns with 2 prevalent but different design approaches. It also discusses future directions for total ankle replacement.

J Orthop Sports Phys Ther. 2000;30(2):56-67.

Key Words: arthritis, arthroplasty, total ankle replacement

Foot orthotics have been used successfully in the treatment of musculoskeletal symptoms associated with structural variations of the foot. Their effectiveness has been primarily addressed through 2-dimensional, frontal plane motion studies of the subtalar joint in individuals considered "clinical pronators. " Recent evidence suggests that assessment of tibial axial rotation in combination with frontal plane analysis of calcaneal inversion/eversion may provide improved understanding of subtalar joint function. The purpose of this study was to examine the effects of semi-rigid foot orthotics on 3-dimensional lower limb kinematics in 20 recreational runners presenting with distinct structural foot characteristics. Radiographic measurements were used to classify subjects into a low or high rearfoot profile group. The results of the kinematic analysis showed a significant orthotic effect for rotations occurring from heel contact to peak tibial internal rotation, as well as in the coupling relationship between tibial axial rotation and calcaneal inversion/eversion. Both groups responded similarly with a mean reduction of 2° in tibial internal rotation. No differences were found for the frontal plane rotations for either group when orthotics were worn. The findings suggest that the maximum effect of orthotics may be realized in the first 50% of stance and related to the changes in tibial axial rotation.

J Orthop Sports Phys Ther. 1995;21(6):317-327.

Key Words: running, kinematics, foot orthotics

The human foot is a unique structure in the animal kingdom, as it is capable of supporting sustained bipedal gait. The foot facilitates upright walking in several ways: 1) load bearing, 2) leverage, 3) shock absorption, 4) balance, and 5) protection. In this article, we discuss the specialized architecture that enables the foot to accomplish these functions.

J Orthop Sports Phys Ther. 1995:21(6):354-360.

Key Words: foot, structure, function