What did the study look at?
One option for osteoarthritis of the inner compartment of the knee (medial compartment osteoarthritis) is the medial opening wedge high tibial osteotomy (MOW-HTO), in which the upper shin bone is opened from the inner side to realign the leg. Patient-specific instrumentation (PSI) consists of cutting and positioning guides made for an individual patient from pre-operative imaging.
The authors note growing interest in PSI as a way to maximise accuracy and minimise major complications, but that no systematic review had yet summarised the clinical literature on PSI for MOW-HTO. The aim was to summarise that evidence.
How was it done?
This is a systematic review: the authors did not treat new patients but searched published studies. In October 2021, PubMed, Scopus and the Cochrane Library were searched for studies that used PSI for MOW-HTO in medial compartment knee osteoarthritis.
The primary outcomes were how closely post-operative measurements matched the planned pre-operative correction. Accuracy was assessed in three ways: the angle seen from the front (mechanical medial proximal tibial angle), the slope seen from the side (posterior tibial slope) and the overall mechanical axis of the leg (measures such as the hip-knee-ankle angle). The secondary outcome was the rate of major complications.
What did it find?
- The review included 14 studies describing eight different PSI techniques.
- The weighted mean error was 0.5° (range 0.1° to 1.3°) for the mechanical medial proximal tibial angle, 0.6° (range 0.3° to 2.7°) for the posterior tibial slope and 0.8° (range 0.1° to 1.0°) for the hip-knee-ankle angle.
- Four studies compared mechanical axis correction error between conventional techniques and PSI. The difference favoured PSI (standardised mean difference 0.52; 95% confidence interval 0.16 to 0.87; p = 0.004).
- Four studies explicitly reported no major complications, while five reported a non-zero rate. Across these nine studies, the weighted mean major complication rate was 7.1% (range 0.0% to 13.0%).
The authors' conclusion
The authors state that the findings suggest PSI for MOW-HTO achieves high accuracy relative to the planned correction in the coronal plane, the sagittal plane and the mechanical axis. They add that the findings suggest a low risk of major complications when PSI is used.
The authors report the level of evidence as "systematic review, level IV". This summary is based on the published abstract, as the full text could not be accessed.
Reference
Dasari SP, Hevesi M, Mameri E, Ferrer-Rivero R, Fortier LM, Jackson GR, Warrier AA, Maheshwer B, Jawanda H, Khan ZA, Kerzner B, Browning RB, Gürsoy S, Chahla J. (2023). Patient-specific instrumentation for medial opening wedge high tibial osteotomies in the management of medial compartment osteoarthritis yields high accuracy and low complication rates: A systematic review. Journal of ISAKOS, 8(3), 163–176. Licence: CC BY 4.0.
DOI: 10.1016/j.jisako.2023.02.001
Free full text: jisakos.com (PDF)
This article summarises a published scientific paper for general information; it does not replace an examination or a personal medical assessment. Please consult your doctor about your symptoms.
