Posterior mini-incision total hip arthroplasty controls the extent of post-operative formation of heterotopic ossification.

D S Edwards,A M J Bull,S A R Barbur,G J Stranks

doi:10.1007/s00590-015-1646-x

Abstract

Heterotopic ossification (HO) is the formation of bone at extra-skeletal sites. Reported rates of HO after hip arthroplasty range from 8 to 90 %; however, it is only severe cases that cause problems clinically, such as joint stiffness. The effects of surgical-related controllable intra-operative risk factors for the formation of HO were investigated. Data examined included gender, age of patient, fat depth, length of operation, incision length, prosthetic fixation method, the use of pulsed lavage and canal brush, and component size and material. All cases were performed by the same surgeon using the posterior approach. A total of 510 cases of hip arthroplasty were included, with an overall rate of HO of 10.2 %. Longer-lasting operations resulted in higher grades of HO (p = 0.047). Incisions >10 cm resulted in more widespread HO formation (p = 0.021). No further correlations were seen between HO formation and fat depth, blood loss, instrumentation, fixation methods or prosthesis material. The mini-incision approach is comparable to the standard approach in the aetiology of HO formation, and whilst the rate of HO may not be controllable, a posterior mini-incision approach can limit its extent.

Highlights

Heterotopic ossification (HO) is the formation of ectopic bone at extra-skeletal sites [1]
No HO on anteroposterior view of the hip Islands of bone within the soft tissues about the hip Bone spurs from the pelvis or femur with [1 cm between opposing ends Bone spurs with reduced space between the opposing bone surface of \1 cm Ankylosis of the hip joint
All cases included were performed by the same surgeon of Consultant grade using the posterior approach to the hip

Summary

Introduction

Heterotopic ossification (HO) is the formation of ectopic bone at extra-skeletal sites [1]. In the case of total hip arthroplasty (THA), it is commonly found in the periarticular capsule and surrounding muscular structures [2]. The rates of HO after hip arthroplasty have been reported to range from 8 to 90 % [3, 4]. It has been shown that grades 3 and 4, the final stage of ankylosis, are the most problematic for patients, commonly complaining of pain and a reduced range of movement [6]. Rates of severe HO range from 3 to 55 % depending on patients and surgical factors present [7]. Established risk factors include male gender, diffuse idiopathic skeletal hyperostosis (DISH), ankylosing spondylitis, previous THA and subsequent HO formation, rheumatoid arthritis, osteonecrosis and previous trauma to the hip [8, 9]. There exists little or weak evidence pertaining to the controllable intra-operative factors such as incision length, blood loss, length of operation, prosthesis type and instrumentation [3,4,5, 7, 8, 10]

Objectives

Methods

Results