Restoring coronal pre-arthritic alignment in mobile-bearing unicompartmental knee arthroplasty: mid- to long-term outcomes

Abstract Background Previous research suggests that restoring pre-arthritic alignment in fixed-bearing unicompartmental knee arthroplasty (UKA) can improve postoperative knee function. However, its applicability to mobile-bearing UKA remains unclear. This study evaluated whether patients who achieve...

Full description

Saved in:
Bibliographic Details
Main Authors: Yankun Jiang, Changquan Liu, Qidong Zhang, Guoyuan Sun, Ran Ding, Nianfei Zhang, Cheng Huang, Weiguo Wang, Wanshou Guo
Format: Article
Language:English
Published: BMC 2025-02-01
Series:BMC Musculoskeletal Disorders
Subjects:
Online Access:https://doi.org/10.1186/s12891-025-08363-y
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1823863588208508928
author Yankun Jiang
Changquan Liu
Qidong Zhang
Guoyuan Sun
Ran Ding
Nianfei Zhang
Cheng Huang
Weiguo Wang
Wanshou Guo
author_facet Yankun Jiang
Changquan Liu
Qidong Zhang
Guoyuan Sun
Ran Ding
Nianfei Zhang
Cheng Huang
Weiguo Wang
Wanshou Guo
author_sort Yankun Jiang
collection DOAJ
description Abstract Background Previous research suggests that restoring pre-arthritic alignment in fixed-bearing unicompartmental knee arthroplasty (UKA) can improve postoperative knee function. However, its applicability to mobile-bearing UKA remains unclear. This study evaluated whether patients who achieve pre-arthritic alignment following mobile-bearing UKA with the kinematic alignment technique experience superior postoperative knee function compared with those who do not. Methods A retrospective analysis was conducted on 236 knee joints that underwent UKA using kinematic alignment techniques between May 2015 and November 2017. Of these, 222 knee joints met the inclusion criteria for the study. Postoperative outcomes were assessed, with pre-arthritic alignment determined using the arithmetic hip-knee-ankle angle (aHKAA). Postoperative alignment within ± 3° of the aHKAA was classified as pre-arthritic alignment. Patients were categorized into two groups: pre-aligned and non-pre-aligned. Final follow-up occurred in September 2024, and outcome measures included the visual analogue scale (VAS) score, Hospital for Special Surgery (HSS) score, and Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales for daily living, sports, and survivorship. Additionally, the percentage of patients meeting the patient-acceptable symptom state (PASS) criteria for KOOS-related subscales was recorded. Failure was defined as conversion to total knee arthroplasty. Results Among the 222 knee joints analyzed, the average follow-up time was 8.65 years (range: 7–9 years), with an average implant survival time of 8.48 years and a total knee arthroplasty conversion rate of 2.7%. The 5-year survival rate was significantly higher in the pre-arthritically aligned group (99.4%) than in the non-pre-arthritically aligned group (92.5%) (p = 0.012). In total, 169 knees (76.13%) were classified as pre-arthritically aligned, while 53 knees (23.87%) were non-pre-arthritically aligned. postoperative VAS scores significantly improved from 6.90 ± 0.82 to 0.58 ± 0.56 (p < 0.001), and HSS scores increased from 56.3 ± 8.36 to 92.39 ± 4.54 (p < 0.001). Although no significant differences in postoperative VAS scores were observed between groups (p = 0.147), the pre-arthritically aligned group demonstrated significantly higher HSS scores and better KOOS subscale scores for daily living activities, sports, and quality of life than the non-pre-arthritically aligned group (all p < 0.01). The PASS ratio for KOOS subscales also indicated superior outcomes in the pre-arthritically aligned group. Conclusion Using the kinematic alignment technique for mobile-bearing UKA, knees that achieved pre-arthritic alignment demonstrated superior survivorship and subjective postoperative knee function compared with those that did not.
format Article
id doaj-art-32fc47d7098441efaaeb4a9bc74a2d1c
institution Kabale University
issn 1471-2474
language English
publishDate 2025-02-01
publisher BMC
record_format Article
series BMC Musculoskeletal Disorders
spelling doaj-art-32fc47d7098441efaaeb4a9bc74a2d1c2025-02-09T12:04:19ZengBMCBMC Musculoskeletal Disorders1471-24742025-02-0126111110.1186/s12891-025-08363-yRestoring coronal pre-arthritic alignment in mobile-bearing unicompartmental knee arthroplasty: mid- to long-term outcomesYankun Jiang0Changquan Liu1Qidong Zhang2Guoyuan Sun3Ran Ding4Nianfei Zhang5Cheng Huang6Weiguo Wang7Wanshou Guo8Department of Orthopaedic Surgery, China-Japan Friendship School of Clinical Medicine, Peking UniversityDepartment of Orthopedics, Shenzhen Second People’s Hospital, First Affiliated Hospital of Shenzhen University Health Science CenterDepartment of Orthopaedic Surgery, China-Japan Friendship HospitalDepartment of Orthopaedic Surgery, China-Japan Friendship HospitalDepartment of Orthopaedic Surgery, China-Japan Friendship HospitalDepartment of Orthopaedic Surgery, China-Japan Friendship HospitalDepartment of Orthopaedic Surgery, China-Japan Friendship HospitalDepartment of Orthopaedic Surgery, China-Japan Friendship HospitalDepartment of Orthopaedic Surgery, China-Japan Friendship HospitalAbstract Background Previous research suggests that restoring pre-arthritic alignment in fixed-bearing unicompartmental knee arthroplasty (UKA) can improve postoperative knee function. However, its applicability to mobile-bearing UKA remains unclear. This study evaluated whether patients who achieve pre-arthritic alignment following mobile-bearing UKA with the kinematic alignment technique experience superior postoperative knee function compared with those who do not. Methods A retrospective analysis was conducted on 236 knee joints that underwent UKA using kinematic alignment techniques between May 2015 and November 2017. Of these, 222 knee joints met the inclusion criteria for the study. Postoperative outcomes were assessed, with pre-arthritic alignment determined using the arithmetic hip-knee-ankle angle (aHKAA). Postoperative alignment within ± 3° of the aHKAA was classified as pre-arthritic alignment. Patients were categorized into two groups: pre-aligned and non-pre-aligned. Final follow-up occurred in September 2024, and outcome measures included the visual analogue scale (VAS) score, Hospital for Special Surgery (HSS) score, and Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales for daily living, sports, and survivorship. Additionally, the percentage of patients meeting the patient-acceptable symptom state (PASS) criteria for KOOS-related subscales was recorded. Failure was defined as conversion to total knee arthroplasty. Results Among the 222 knee joints analyzed, the average follow-up time was 8.65 years (range: 7–9 years), with an average implant survival time of 8.48 years and a total knee arthroplasty conversion rate of 2.7%. The 5-year survival rate was significantly higher in the pre-arthritically aligned group (99.4%) than in the non-pre-arthritically aligned group (92.5%) (p = 0.012). In total, 169 knees (76.13%) were classified as pre-arthritically aligned, while 53 knees (23.87%) were non-pre-arthritically aligned. postoperative VAS scores significantly improved from 6.90 ± 0.82 to 0.58 ± 0.56 (p < 0.001), and HSS scores increased from 56.3 ± 8.36 to 92.39 ± 4.54 (p < 0.001). Although no significant differences in postoperative VAS scores were observed between groups (p = 0.147), the pre-arthritically aligned group demonstrated significantly higher HSS scores and better KOOS subscale scores for daily living activities, sports, and quality of life than the non-pre-arthritically aligned group (all p < 0.01). The PASS ratio for KOOS subscales also indicated superior outcomes in the pre-arthritically aligned group. Conclusion Using the kinematic alignment technique for mobile-bearing UKA, knees that achieved pre-arthritic alignment demonstrated superior survivorship and subjective postoperative knee function compared with those that did not.https://doi.org/10.1186/s12891-025-08363-yUnicompartmental knee arthroplastySurgical techniquePre-arthritic alignment
spellingShingle Yankun Jiang
Changquan Liu
Qidong Zhang
Guoyuan Sun
Ran Ding
Nianfei Zhang
Cheng Huang
Weiguo Wang
Wanshou Guo
Restoring coronal pre-arthritic alignment in mobile-bearing unicompartmental knee arthroplasty: mid- to long-term outcomes
BMC Musculoskeletal Disorders
Unicompartmental knee arthroplasty
Surgical technique
Pre-arthritic alignment
title Restoring coronal pre-arthritic alignment in mobile-bearing unicompartmental knee arthroplasty: mid- to long-term outcomes
title_full Restoring coronal pre-arthritic alignment in mobile-bearing unicompartmental knee arthroplasty: mid- to long-term outcomes
title_fullStr Restoring coronal pre-arthritic alignment in mobile-bearing unicompartmental knee arthroplasty: mid- to long-term outcomes
title_full_unstemmed Restoring coronal pre-arthritic alignment in mobile-bearing unicompartmental knee arthroplasty: mid- to long-term outcomes
title_short Restoring coronal pre-arthritic alignment in mobile-bearing unicompartmental knee arthroplasty: mid- to long-term outcomes
title_sort restoring coronal pre arthritic alignment in mobile bearing unicompartmental knee arthroplasty mid to long term outcomes
topic Unicompartmental knee arthroplasty
Surgical technique
Pre-arthritic alignment
url https://doi.org/10.1186/s12891-025-08363-y
work_keys_str_mv AT yankunjiang restoringcoronalprearthriticalignmentinmobilebearingunicompartmentalkneearthroplastymidtolongtermoutcomes
AT changquanliu restoringcoronalprearthriticalignmentinmobilebearingunicompartmentalkneearthroplastymidtolongtermoutcomes
AT qidongzhang restoringcoronalprearthriticalignmentinmobilebearingunicompartmentalkneearthroplastymidtolongtermoutcomes
AT guoyuansun restoringcoronalprearthriticalignmentinmobilebearingunicompartmentalkneearthroplastymidtolongtermoutcomes
AT randing restoringcoronalprearthriticalignmentinmobilebearingunicompartmentalkneearthroplastymidtolongtermoutcomes
AT nianfeizhang restoringcoronalprearthriticalignmentinmobilebearingunicompartmentalkneearthroplastymidtolongtermoutcomes
AT chenghuang restoringcoronalprearthriticalignmentinmobilebearingunicompartmentalkneearthroplastymidtolongtermoutcomes
AT weiguowang restoringcoronalprearthriticalignmentinmobilebearingunicompartmentalkneearthroplastymidtolongtermoutcomes
AT wanshouguo restoringcoronalprearthriticalignmentinmobilebearingunicompartmentalkneearthroplastymidtolongtermoutcomes