Elsevier

Clinical Biomechanics

Volume 24, Issue 10, December 2009, Pages 812-818
Clinical Biomechanics

A prospective randomized assessment of earlier functional recovery in THA patients treated by minimally invasive direct anterior approach: A gait analysis study

https://doi.org/10.1016/j.clinbiomech.2009.07.010Get rights and content

Abstract

Background

Total hip replacement using a minimally invasive surgical approach is claimed to enable recovering of motor function more quickly. The purpose of this prospective As per the stylesheet, kindly provide section headings for abstract.and randomized study was to test this claim by evaluating early patient functional outcomes by gait analysis.

Methods

Seventeen patients were operated on using a traditional anterolateral approach (AL), 16 using a minimally invasive direct anterior approach (DA). Gait analysis was performed the day before surgery, and at 6 and 12 weeks after surgery. Time–distance and kinematics analyses were performed by a recently proposed anatomically-based gait analysis protocol. A static double-leg stance and five walking trials at self-selected speeds were recorded on a 9-m walkway.

Findings

At 6 weeks follow-up, but in the DA group only, a statistically significant improvement with respect to preoperative status was observed for the percentage of single support and for the stride time. Between 6- and 12-week follow-up, the DA group showed a significant improvement in cadence, stride time and length, walking speed, hip flexion at foot contact, maximum hip flexion in swing, and hip total range of motion in the sagittal and the coronal planes. Between 6 and 12 weeks, the AL group showed significant improvements in opposite foot contact and step time, and in flexion at foot contact, maximum flexion in swing, and range of flexion at the hip joint.

Interpretation

Minimally invasive DA patients improved in a larger number of gait parameters than patients receiving the traditional AL approach. The majority of improvements occurred between the 6- and 12-week follow-ups.

Introduction

Despite the success of total hip arthroplasty (THA) in terms of pain relief, quality of life, and physical function, some THA patients still do not achieve normal gait at 1 year or more after surgery (Long et al., 1993, McCrory et al., 2001, Murray et al., 1972, Perron et al., 2000, Rigas and Xenakis, 1988, Ritter et al., 2001, Stauffer et al., 1974). This might be explained by the effect of the surgical approach on the function of those muscles in the vicinity of the hip joint. The anterolateral (AL) surgical approach is done using the transgluteal route, which involves the gluteus medius, vastus lateralis, and external rotators (Rachbauer, 2006). Anatomically, the gluteus muscles are responsible for controlling pelvic obliquity during gait and hip abduction (Crenshaw, 1992). The effect of the surgical approach on the function of hip abductor muscles was addressed extensively (Baker and Bitounis, 1989, Downing et al., 2001, Gore et al., 1982, Murray et al., 1971, Stauffer et al., 1974, Tanaka, 1998, Vaz et al., 1993, Vicar and Coleman, 1984), and positive results for the AL approach were shown in the static Trendelenburg test, which indicates postoperative hip abductor dysfunction.

More recently, minimally invasive surgical approaches in THA have been introduced and are currently being discussed widely in the medical community (Goldstein et al., 2003, Howell et al., 2004, Keggi et al., 1993, Ogonda et al., 2005, Rachbauer, 2006). This is accomplished by minimizing cutting through the muscles. In an effort to potentially minimize muscle trauma during surgery, a minimally invasive direct anterior (DA) approach via the ‘Smith-Peterson’ interval was developed at our department (Nogler et al., 2008, Rachbauer, 2006). This approach, which requires the use of special instruments, allows exposure and implantation of the prosthesis components without cutting through hip muscles. It uses the intermuscular plane between the gluteus and the tensor muscles laterally, and the sartorius and rectus muscles medially.

The clinical outcome of both AL and DA approaches is encouraging, but quantitative data, particularly those concerning postoperative functional differences during gait, are very limited (Tanaka, 1998, Keggi et al., 1993, Ritter et al., 1995). Gait analysis is now an established technique, and has been used successfully to quantify the effect of various surgical orthopedic treatments on patients with coxarthrosis (Hurwitz et al., 1997). Most recently it has been used to try to demonstrate possible advantages of common and minimally invasive surgical approaches in THA (Bennett et al., 2007, Meneghini et al., 2008, Whatling et al., 2008, Ward et al., 2008) but these did not succeed to demonstrate functional advantages related to surgical procedure. In addition, functional outcome of the DA approach has been limitedly assessed quantitatively as the only paper reporting on this and other minimally invasive approaches (Ward et al., 2008) used a simple device for the monitoring of the physical activities, reporting only time–distance parameters.

The purpose of this study was to test the hypothesis that patients operated on by the minimally invasive DA approach have an earlier return to normal function than patients operated on by the traditional AL approach. This was evaluated using gait analysis data set collected over a large cohort of THA patients at early follow-ups.

Section snippets

Methods

Patients in this prospective, randomized study were evaluated preoperatively and at 6 and 12 weeks postoperatively. Time–distance and segment and joint kinematics were obtained by gait analysis on two groups of adult patients. The study was conducted in accordance with current Austrian regulations, and written informed consent was obtained from all patients. All patients had unilateral hip disease. Co-morbidities of the lower extremity, such as osteoarthritis or misalignment at other joints

Sample characteristics

In the DA group the median age was 66 (±10) years, median weight 76 kg, and median height 168.0 cm. In the AL group these values were, respectively, 68 (±10) years, 84 kg, height 168.5 cm. No significant differences were found in WOMAC in the dimension of pain, stiffness and function between the two groups as well as for LLD at any follow-up (Table 1) .

Surgical information

In the DA group, the mean surgical time was 70 min (range of 60–85 min), and the mean blood loss was 264 cc (range of 150–450 cc). In the AL group these

Discussion

State-of-the-art gait analysis was used to investigate postoperatively the functional assessment of patients who had undergone THA either by the traditional AL approach or the minimally invasive DA approach. The former approach is known to affect the abductor muscles, which stabilize the pelvis (Crenshaw, 1992), whereas the DA approach should cause no harm to the muscles (Rachbauer, 2006, Krismer and Rachbauer, 2004, Meneghini et al., 2006). With this approach, an anterolateral flap of the

Conflict of interest

The authors declare that they do not have any financial or personal relationships with other people or organizations that could have inappropriately influenced this study.

Acknowledgements

The authors would like to thank Markus Ertl, PhD, for performing the statistical analysis, Stefan Fischler for his support in the Innsbruck gait laboratory, and Stefania Ingrosso, MEng, for the data processing in Bologna.

References (42)

  • M. Perron et al.

    Three-dimensional gait analysis in women with a total hip arthroplasty

    Clin. Biomech.

    (2000)
  • M.A. Ritter et al.

    Comparative outcomes of total joint arthroplasty

    J. Arthroplasty

    (1995)
  • G. Wu et al.

    ISB recommendations for standardization in the reporting of kinematic data

    J. Biomech.

    (1995)
  • G. Wu et al.

    Standardization and Terminology Committee of the International Society of Biomechanics. ISB recommendation on definitions of joint coordinate system of various joints for the reporting of human joint motion – part I: ankle, hip, and spine. International Society of Biomechanics

    J. Biomech.

    (2002)
  • A.S. Baker et al.

    Abductor function after total hip replacement. An electromyographic and clinical review

    J. Bone Joint Surg. Br.

    (1989)
  • R. Bauer et al.

    The transgluteal approach to the hip joint

    Arch. Orthop. Trauma Surg.

    (1979)
  • N. Bellamy et al.

    Validation study of WOMAC: a health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee

    J. Rheumatol.

    (1988)
  • A. Crenshaw

    Surgical Approaches

    (1992)
  • N.D. Downing et al.

    Hip abductor strength following total hip arthroplasty: a prospective comparison of the posterior and lateral approach in 100 patients

    Acta Orthop. Scand.

    (2001)
  • W.M. Goldstein et al.

    Minimal-incision total hip arthroplasty

    J. Bone Joint Surg. Am.

    (2003)
  • D.R. Gore et al.

    Anterolateral compared to posterior approach in total hip arthroplasty: differences in component positioning, hip strength, and hip motion

    Clin. Orthop. Relat. Res.

    (1982)
  • Cited by (161)

    View all citing articles on Scopus
    View full text