Bony ankylosis adversely affects postoperative hip function in patients with ankylosing spondylitis undergoing total hip arthroplasty: a retrospective cohort study of 319 consecutive patients

Abstract Background This study reports the mid-term outcomes of primary total hip arthroplasty (THA) and investigates the effect of bony ankylosis on postoperative hip function in patients with ankylosing spondylitis (AS). Methods We identified 544 primary THAs performed in 319 consecutive patients...

Full description

Saved in:
Bibliographic Details
Main Authors: Liangliang Li, Jun Fu, Chi Xu, Ming Ni, Wei Chai, Libo Hao, Yonggang Zhou, Jiying Chen
Format: Article
Language:English
Published: BMC 2025-02-01
Series:BMC Musculoskeletal Disorders
Subjects:
Online Access:https://doi.org/10.1186/s12891-025-08369-6
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1823863629831733248
author Liangliang Li
Jun Fu
Chi Xu
Ming Ni
Wei Chai
Libo Hao
Yonggang Zhou
Jiying Chen
author_facet Liangliang Li
Jun Fu
Chi Xu
Ming Ni
Wei Chai
Libo Hao
Yonggang Zhou
Jiying Chen
author_sort Liangliang Li
collection DOAJ
description Abstract Background This study reports the mid-term outcomes of primary total hip arthroplasty (THA) and investigates the effect of bony ankylosis on postoperative hip function in patients with ankylosing spondylitis (AS). Methods We identified 544 primary THAs performed in 319 consecutive patients with AS (median age, 33 years) from 2012 to 2017. Survivorship of the implants, complications, and patient satisfaction were investigated. Functional outcomes were assessed by the measurement of hip flexion–extension range of motion (ROM), the Harris hip score (HHS), and the Western Ontario and McMaster Universities Arthritis Index (WOMAC). The hips undergoing THA were divided into a bony ankylosis group and a hip stiffness group based on the severity of hip involvement. The postoperative functional results of the two groups at the most recent follow-up were compared. Results Survivorship was 99.8% with a mean follow-up of 7 years (range, 5–9 years). The main complications included dislocation (5 hips, 0.9%), periprosthetic femoral fracture (15 hips, 2.7%), and infection (primary infection in 2 hips and periprosthetic joint infection in 1 hip, 0.6%). The flexion–extension ROM improved significantly with a median of 0° (0 ~ 120°) pre-operatively to 100° (30 ~ 130°) after THA (P < 0.001), and the HHS improved from 37 ± 19 to 90 ± 5 (P < 0.001). Patient satisfaction was self-scored as ‘Very satisfied’ in 278 (87%) of patients. The most common cause of dissatisfaction in the remaining 41 (13%) patients was poor hip flexion function (58.5% of this subset). Postoperative ROM was significantly lower in the bony ankylosis hips (median, 100° bony ankylosis group vs. 110° hip stiffness group). The bony ankylosis group also had lower postoperative HHS (89 ± 5 vs. 92 ± 5) and had significantly higher WOMAC scores (43 ± 20 vs. 31 ± 18) than the hip stiffness group (P < 0.001). Conclusions Excellent mid-term clinical outcomes can be achieved with modern cementless THA in patients with AS. Poor hip flexion function is the main complaint of patients who are dissatisfied with their outcomes. Bony ankylosis has adverse effects on postoperative hip function in patients with AS, suggesting that performing THA before ankylosis occurs can lead to better subjective outcomes and better postoperative hip function. Level of evidence Level III.
format Article
id doaj-art-bc4416cb7bdf40a6af725001103f5a74
institution Kabale University
issn 1471-2474
language English
publishDate 2025-02-01
publisher BMC
record_format Article
series BMC Musculoskeletal Disorders
spelling doaj-art-bc4416cb7bdf40a6af725001103f5a742025-02-09T12:04:18ZengBMCBMC Musculoskeletal Disorders1471-24742025-02-0126111010.1186/s12891-025-08369-6Bony ankylosis adversely affects postoperative hip function in patients with ankylosing spondylitis undergoing total hip arthroplasty: a retrospective cohort study of 319 consecutive patientsLiangliang Li0Jun Fu1Chi Xu2Ming Ni3Wei Chai4Libo Hao5Yonggang Zhou6Jiying Chen7Department of Orthopedics, the Second Hospital of Shanxi Medical UniversityDepartment of Orthopedics, the First Medical Centre, Chinese PLA General HospitalDepartment of Orthopedics, the First Medical Centre, Chinese PLA General HospitalDepartment of Orthopedics, the First Medical Centre, Chinese PLA General HospitalDepartment of Orthopedics, the First Medical Centre, Chinese PLA General HospitalDepartment of Orthopedics, the First Medical Centre, Chinese PLA General HospitalDepartment of Orthopedics, the First Medical Centre, Chinese PLA General HospitalDepartment of Orthopedics, the First Medical Centre, Chinese PLA General HospitalAbstract Background This study reports the mid-term outcomes of primary total hip arthroplasty (THA) and investigates the effect of bony ankylosis on postoperative hip function in patients with ankylosing spondylitis (AS). Methods We identified 544 primary THAs performed in 319 consecutive patients with AS (median age, 33 years) from 2012 to 2017. Survivorship of the implants, complications, and patient satisfaction were investigated. Functional outcomes were assessed by the measurement of hip flexion–extension range of motion (ROM), the Harris hip score (HHS), and the Western Ontario and McMaster Universities Arthritis Index (WOMAC). The hips undergoing THA were divided into a bony ankylosis group and a hip stiffness group based on the severity of hip involvement. The postoperative functional results of the two groups at the most recent follow-up were compared. Results Survivorship was 99.8% with a mean follow-up of 7 years (range, 5–9 years). The main complications included dislocation (5 hips, 0.9%), periprosthetic femoral fracture (15 hips, 2.7%), and infection (primary infection in 2 hips and periprosthetic joint infection in 1 hip, 0.6%). The flexion–extension ROM improved significantly with a median of 0° (0 ~ 120°) pre-operatively to 100° (30 ~ 130°) after THA (P < 0.001), and the HHS improved from 37 ± 19 to 90 ± 5 (P < 0.001). Patient satisfaction was self-scored as ‘Very satisfied’ in 278 (87%) of patients. The most common cause of dissatisfaction in the remaining 41 (13%) patients was poor hip flexion function (58.5% of this subset). Postoperative ROM was significantly lower in the bony ankylosis hips (median, 100° bony ankylosis group vs. 110° hip stiffness group). The bony ankylosis group also had lower postoperative HHS (89 ± 5 vs. 92 ± 5) and had significantly higher WOMAC scores (43 ± 20 vs. 31 ± 18) than the hip stiffness group (P < 0.001). Conclusions Excellent mid-term clinical outcomes can be achieved with modern cementless THA in patients with AS. Poor hip flexion function is the main complaint of patients who are dissatisfied with their outcomes. Bony ankylosis has adverse effects on postoperative hip function in patients with AS, suggesting that performing THA before ankylosis occurs can lead to better subjective outcomes and better postoperative hip function. Level of evidence Level III.https://doi.org/10.1186/s12891-025-08369-6Ankylosing spondylitisInflammatory arthritisHip ankylosisTotal hip arthroplastyHip functionPatient dissatisfaction
spellingShingle Liangliang Li
Jun Fu
Chi Xu
Ming Ni
Wei Chai
Libo Hao
Yonggang Zhou
Jiying Chen
Bony ankylosis adversely affects postoperative hip function in patients with ankylosing spondylitis undergoing total hip arthroplasty: a retrospective cohort study of 319 consecutive patients
BMC Musculoskeletal Disorders
Ankylosing spondylitis
Inflammatory arthritis
Hip ankylosis
Total hip arthroplasty
Hip function
Patient dissatisfaction
title Bony ankylosis adversely affects postoperative hip function in patients with ankylosing spondylitis undergoing total hip arthroplasty: a retrospective cohort study of 319 consecutive patients
title_full Bony ankylosis adversely affects postoperative hip function in patients with ankylosing spondylitis undergoing total hip arthroplasty: a retrospective cohort study of 319 consecutive patients
title_fullStr Bony ankylosis adversely affects postoperative hip function in patients with ankylosing spondylitis undergoing total hip arthroplasty: a retrospective cohort study of 319 consecutive patients
title_full_unstemmed Bony ankylosis adversely affects postoperative hip function in patients with ankylosing spondylitis undergoing total hip arthroplasty: a retrospective cohort study of 319 consecutive patients
title_short Bony ankylosis adversely affects postoperative hip function in patients with ankylosing spondylitis undergoing total hip arthroplasty: a retrospective cohort study of 319 consecutive patients
title_sort bony ankylosis adversely affects postoperative hip function in patients with ankylosing spondylitis undergoing total hip arthroplasty a retrospective cohort study of 319 consecutive patients
topic Ankylosing spondylitis
Inflammatory arthritis
Hip ankylosis
Total hip arthroplasty
Hip function
Patient dissatisfaction
url https://doi.org/10.1186/s12891-025-08369-6
work_keys_str_mv AT liangliangli bonyankylosisadverselyaffectspostoperativehipfunctioninpatientswithankylosingspondylitisundergoingtotalhiparthroplastyaretrospectivecohortstudyof319consecutivepatients
AT junfu bonyankylosisadverselyaffectspostoperativehipfunctioninpatientswithankylosingspondylitisundergoingtotalhiparthroplastyaretrospectivecohortstudyof319consecutivepatients
AT chixu bonyankylosisadverselyaffectspostoperativehipfunctioninpatientswithankylosingspondylitisundergoingtotalhiparthroplastyaretrospectivecohortstudyof319consecutivepatients
AT mingni bonyankylosisadverselyaffectspostoperativehipfunctioninpatientswithankylosingspondylitisundergoingtotalhiparthroplastyaretrospectivecohortstudyof319consecutivepatients
AT weichai bonyankylosisadverselyaffectspostoperativehipfunctioninpatientswithankylosingspondylitisundergoingtotalhiparthroplastyaretrospectivecohortstudyof319consecutivepatients
AT libohao bonyankylosisadverselyaffectspostoperativehipfunctioninpatientswithankylosingspondylitisundergoingtotalhiparthroplastyaretrospectivecohortstudyof319consecutivepatients
AT yonggangzhou bonyankylosisadverselyaffectspostoperativehipfunctioninpatientswithankylosingspondylitisundergoingtotalhiparthroplastyaretrospectivecohortstudyof319consecutivepatients
AT jiyingchen bonyankylosisadverselyaffectspostoperativehipfunctioninpatientswithankylosingspondylitisundergoingtotalhiparthroplastyaretrospectivecohortstudyof319consecutivepatients