Post-Total Knee Arthroplasty Patellar Instability due to Extensor Mechanism Malalignment: A Novel Technique for Management.
- 1Department of Orthopedics, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
- 2Orthopedic Research Center, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran.
- 3Department of Orthopedic Surgery, Orthopedic Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Abstract
Persistent patellar instability after total knee arthroplasty due to extensor mechanism malalignment poses a significant clinical challenge when prosthetic components are well-fixed and adequately aligned. Revision arthroplasty carries considerable morbidity in these patients. We describe a reproducible soft tissue reconstruction technique using a fresh-frozen Achilles tendon allograft without bone block to reconstruct the medial retinacular stabilizers and redirect the extensor force vector. The allograft is fixed at the femoral medial patellofemoral ligament attachment, passed across the anterior patella, and anchored to provide robust medial restraint without prosthetic revision. In two illustrative cases with ≥24 months of follow-up, central patellar tracking was restored, subjective instability resolved, and no recurrent dislocation or extensor lag occurred.
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BibTeX
@article{ariamanesh2026posttotal,
title = {{Post-Total Knee Arthroplasty Patellar Instability due to Extensor Mechanism Malalignment: A Novel Technique for Management.}},
author = {Amir Shahriar Ariamanesh and Moslem Falah Kezabi and Amir Moayedpour},
journal = {Arthroplasty today},
year = {2026},
month = oct,
doi = {10.1016/j.artd.2026.102177},
url = {https://europepmc.org/article/MED/42920968},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - Post-Total Knee Arthroplasty Patellar Instability due to Extensor Mechanism Malalignment: A Novel Technique for Management.
AU - Amir Shahriar Ariamanesh
AU - Moslem Falah Kezabi
AU - Amir Moayedpour
PY - 2026
DA - 2026/10/19
JO - Arthroplasty today
DO - 10.1016/j.artd.2026.102177
UR - https://europepmc.org/article/MED/42920968
AB - Persistent patellar instability after total knee arthroplasty due to extensor mechanism malalignment poses a significant clinical challenge when prosthetic components are well-fixed and adequately aligned. Revision arthroplasty carries considerable morbidity in these patients. We describe a reproducible soft tissue reconstruction technique using a fresh-frozen Achilles tendon allograft without bone block to reconstruct the medial retinacular stabilizers and redirect the extensor force vector. The allograft is fixed at the femoral medial patellofemoral ligament attachment, passed across the anterior patella, and anchored to provide robust medial restraint without prosthetic revision. In two illustrative cases with ≥24 months of follow-up, central patellar tracking was restored, subjective instability resolved, and no recurrent dislocation or extensor lag occurred.
SN - 2352-3441
ER -