Plantar Pressure Distribution during Standing in Female Patients with Hip Osteoarthritis Who Underwent Total Hip Arthroplasty

Research Article

Phys Med Rehabil Int. 2021; 8(3): 1182.

Plantar Pressure Distribution during Standing in Female Patients with Hip Osteoarthritis Who Underwent Total Hip Arthroplasty

Miura M¹*, Nagai K², Tagomori K³, Ikutomo H¹, Okamura K¹, Okuno T¹, Yanamoto A¹, Nakagawa N¹ and Masuhara K¹

1Masuhara Clinic, Tenmabashi, Kita-ku, Osaka, Japan

2Department of Physical Therapy, School of Rehabilitation, Hyogo University of Health Sciences, Kobe, Japan

*Corresponding author: Namika Miura, Masuhara Clinic, 3-4-2, Tenmabashi, Kita-ku, Osaka 530-0042, Japan

Received: June 08, 2021; Accepted: July 13, 2021; Published: July 20, 2021

Abstract

Introduction: Assessment of plantar pressure indicates the manner in which the plantar region contacts the ground as the first point in a leg-linked kinetic chain, and receives force from the ground. However, few studies have examined the changes in plantar pressure distribution in patients who underwent Total Hip Arthroplasty (THA) before and after THA, or compared plantar pressure distribution between THA patients and healthy adults.

Objective: Plantar pressure distribution in patients with end-stage hip osteoarthritis who undergo THA may be adjusted to that in healthy adults by correcting leg length discrepancy. Herein, our objective was to find out if the plantar pressure distribution during standing differs before and after THA, and between healthy adults and THA patients.

Design: Case control study.

Setting: Single orthopedic clinic in Japan.

Participants: THA patients (n=58; THA group) and healthy adults (n=53; control group).

Interventions: Not applicable.

Main outcome measure(s): The maximum plantar pressure under each foot measured during standing for 20 s was assessed for location, symmetry, and leg length discrepancy.

Results: The distribution plantar pressure in the THA group differed preand postoperatively. The maximum plantar pressure region was the heel in approximately 80% of the patients three months after THA; it was not different in THA patients three months postoperatively and in healthy adults. Patients with asymmetrical maximum plantar pressure regions were those whose postoperative maximum plantar pressure region in the affected leg was the forefoot and those whose maximum plantar pressure region in the affected leg shifted to the heel. The leg length discrepancies decreased significantly after THA.

Conclusions: The plantar pressure distribution during standing in female patients adjusted to that in healthy adults after THA. Patients with asymmetrical distribution of maximum plantar pressure may benefit from balance assessment and physical therapy.

Keywords: Total hip arthroplasty; Plantar pressure; Osteoarthritis

Introduction

The feet are the first and, in general, the only part of the body that contact the external environment directly during standing. In addition, the foot provides sensory information regarding contact with the ground [1,2]. A number of systems that measure foot pressure are available, but the results of one system should not generally be compared with another [3,4]. It may be clinically important to measure the distribution of plantar pressure rather than its value. Plantar pressure distribution can be influenced by factors such as weight, age, sex, anatomical structure of the foot, joint range of motion, and sports activities [5,6]. We have shown that the leg length discrepancy in patients with end-stage hip Osteoarthritis (OA) predicted their plantar pressure distribution. We have also shown that the plantar pressure is higher in the heel in approximately 80% of healthy women and 65% of patients with end-stage hip OA and higher in the forefoot in approximately 25% of these patients [7]. Assessment of plantar pressure indicates how the plantar region contacts the ground as the first point in a leg-linked kinetic chain and how the plantar region receives force from the ground. Periyasamy et al. described that pressure distribution measurement techniques are useful for understanding the biomechanics of the human foot and addressing various concerns regarding associations between plantar pressure distribution and lower-extremity posture [2,5]. However, few studies have examined how plantar pressure distribution in patients who underwent Total Hip Arthroplasty (THA) changed from before THA to after THA or compared plantar pressure distribution between THA patients and healthy adults.

For this study, we hypothesized that the plantar pressure distribution during standing in patients with end-stage hip OA can be adjusted to that of healthy adults after THA resulting from correction of leg length discrepancies. Thus, this study aimed to investigate how plantar pressure distribution during standing in patients who underwent THA changed from before THA and to clarify whether plantar pressure distribution during standing in patients with THA differs from that of healthy adults.

Methods

Participants

The present study employed the case control study design. In 2016, 143 patients with end-stage hip OA (Kellgren and Lawrence Grading System: grade 4) were admitted to our institution for primary THA. Of these patients, we excluded men (n=18) and selected only women to control for sex-specific differences in plantar pressure distribution [5]. In addition, we excluded the following patients: those with OA in both hip joints (n=13), those who had undergone contralateral THA (n=42), those who had severe limitation in their ankle range of motion (n=1), and those who could not be assessed for any other reasons before, one month after, and three months after THA (n=7, n=3, and n=1, respectively). A total of 58 patients [mean age 62.9 {standard deviation (SD) 9.9} years, Body Mass Index (BMI) 22.9 (SD 3.2) kg/m²; THA group] participated in this study (Figure 1).