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Jt Dis Relat Surg
Jt Dis Relat Surg
Joint Diseases and Related Surgery
2687-4784
2687-4792
Bayçınar Medical Publishing

10.52312/jdrs.2024.57924
39189568
Review
Established practices and future insights into patellar instability surgery: A review
Bahadır Batuhan http://orcid.org/0000-0002-4651-1063
1
Aras Sezgin Erdem http://orcid.org/0000-0001-5869-6571
2
Atik O. Şahap http://orcid.org/0000-0002-2162-8070
3
1 Department of Orthopedics and Traumatology, Bilkent City Hospital, Ankara, Türkiye
2 Department of Orthopedics and Traumatology, Gazi University Faculty of Medicine, Ankara, Türkiye
3 President, Turkish Joint Diseases Foundation, Ankara, Türkiye
O. Şahap Atik, MD. Turkish Joint Diseases Foundation, Mustafa Kemal Mah., Dumlupınar Bul., 274/2, C2 Blok, Ofis 5, 06900 Çankaya, Ankara, Türkiye. satikmd@gmail.com.
9 2024
14 8 2024
35 3 594595
29 7 2024
29 7 2024
Copyright © 2024, Turkish Joint Diseases Foundation
2024
Turkish Joint Diseases Foundation
https://creativecommons.org/licenses/by-nc/4.0/ This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
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pmcManagement of patellar instability poses a significant challenge, as the condition stems from a combination of static and dynamic abnormalities of bone or soft tissue structures. The conventional diagnostics focus on the physical examination findings of patellar maltracking and assessment of anatomical abnormalities such as trochlear dysplasia, patella alta, and increased tibial tubercle-trochlear groove (TT-TG) distance on plain X-rays and magnetic resonance imaging, which are static, two-dimensional modalities.[1] Depending on the underlying anatomy, the surgical treatment typically includes a medial patellofemoral ligament (MPFL) reconstruction and a combination of accompanying procedures such as tibial tubercle osteotomy, trochleoplasty or other osteotomies. However, contemporary research points out the necessity of a more comprehensive evaluation of different concepts, bringing intense discourse regarding surgical choices.

Patellar instability is currently increasingly being evaluated as a dynamic problem of the extensor mechanism, whose behavior varies depending on the position of the hip and knee joints and the amount of weight the extremity bears at any given time.[2] With the utilization of dynamic imaging, parameters such as TT-TG distance, patellar tilt, height and bisect offset have been shown to significantly change with the flexion of the knee and weight bearing.[3] These findings raise questions about the validity of traditional imaging.

The entire extensor mechanism, including the dynamic and static structures that generate a force vector or provide resistance are currently being evaluated as parameters for disruption of normal patellar tracking.[4] Moreover, rotational deformities in the proximal femur and between the distal femur and proximal tibia should also be recognized as commonly overlooked culprits of low energy or recurrent dislocations since they affect the system in a way which produces a force vector influencing the patellar stability.[5]

Despite the increasing debate on appropriate management of these patients with more advanced deformities or failed surgeries, biomechanical outcome of the proposed surgical corrections remains largely unexplored. It should be kept in mind that a combination of surgeries may restore patellar tracking in expense of natural patellofemoral loading, which ultimately leads to unsatisfactory outcome. Biomechanical studies on cadavers are commonly performed to answer such questions; however, testing a vast number of deformities and clinical scenarios poses challenges in feasibility and cost. At this point, finite element analysis offers unique opportunities to comprehend the complex three-dimensional geometry, the dynamic effect of structures with varying mechanical characteristics as well as accurate assessment of contact pressures.[6-8] On top of its potential future use in testing various surgical methods for various deformities, it can be speculated that computational simulation demonstrates a merit in becoming a tool for planning patellofemoral surgery in the future, even on an individual basis.

Financial Disclosure

The authors received no financial support for the research and/or authorship of this article.

Data Sharing Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Conflict of Interest: The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Author Contributions: All authors contributed equally to the article.

Citation: Bahadır B, Sezgin EA, Atik OŞ. Established practices and future insights into patellar instability surgery: A review. Jt Dis Relat Surg 2024;35(3):594-595. doi: 10.52312/jdrs.2024.57924.
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