Table 1.

Summary of laboratory studies

Study	Country	Study type	Implant	Summary	Study quality *
Campi et al. [16]	UK	Sawbone	Oxford (Biomet)	This study suggests that decreasing the press fit of the tibial keel of the cementless UKA would significantly decrease the push-in force required to insert the tibial component (and so decrease the risk of fracture), without reducing the pull-out force and therefore ensuring the same level of primary stability	Good
Chang et al. [19]	Taiwan	FE model & Sawbone	Miller-Galante II, cemented (Zimmer)	This study suggests that in UKA, rounding the resection corner during preparation of the tibial plateau decreases the strain on tibial bone and avoid degenerative remodeling, in comparison to a standard rectangular corner. This modified surgical technique using a predrilled tunnel through the tibia prior to cutting could avoid extended vertical saw cutting errors	Good
Clarius et al. [20]	Germany	Sawbone	Oxford (Biomet)	This study suggests several sawing errors can occur during preparation of the tibial plateau (extended vertical cuts which may reduce the stability of the medial tibial plateau, extended horizontal cuts, perforation of the posterior cortex) and femoral condyle (ascending cut at the posterior femoral condyle) in UKA, especially with inexperienced surgeons	Good
Clarius et al. [21]	Germany	Cadaver	Oxford UKA (Biomet)	This study suggests that extended sagittal saw cuts in UKA weaken the tibial bone structure and increase the risk of periprosthetic tibial plateau fractures. In addition, this study showed that UKA patients with low BMD are at higher risk, as the fracture load is dependent on the bone density	Good
Iesaka et al. [41]	Japan	FE model	NR	In UKA, placing the tibial component in slight valgus inclination is preferred to varus or square inclination as it results in more even stress distributions	Fair
Inoue et al. [42]	Japan	FE model	Metal-backed tibia, cemented	This study suggests that the risk of medial tibial condylar fractures in UKA increases with increasing valgus inclination of the tibial component and with increased extension of the sagittal cut in the posterior tibial cortex	Good
Mohammad et al. 2018	UK	Sawbone	Oxford, cementless (Zimmer Biomet)	This study suggests to use a new wider and deeper keel cut saw blade in UKA as it decreases the risk of tibial fracture compared to the standard keel cut saw blade, with no compromise in fixation	Good
Sasatani et al. 2019	Japan	FE model	Persona (Zimmer Biomet)	This study suggests that the optimal alignment of the tibial implant in UKA is the middle position the coronal plane and the original posterior inclination in the sagittal plane	Good
Sawatari et al. 2005	Japan	FE model	SCR UKA, metal-backed tibia, cemented (Stryker)	This study suggests that in UKA, placing the tibial component in slight valgus inclination is recommended due to reduced stress on tibial cancellous bone, in comparison with varus or square inclination. However, excessive posterior slope should be avoided	Good
Seeger et al. [79]	Germany	Cadaver	Oxford cemented & cementless (Biomet)	The risk for periprosthetic tibial plateau fractures is higher with cementless UKA than cemented UKA, especially in patients with poor bone quality	Good
Seeger et al. [80]	Germany	Cadaver	Oxford (Biomet)	Concerning the treatment of periprosthetic tibial plateau fractures in UKA, angle-stable plates provides better initial stability than fixation with cannulated screws	Good
Pegg et al. [71]	UK	FE model and Sawbone	Oxford (Biomet)	This study suggests that excessive resection depth and making the vertical cut too deep posteriorly increase the risk for periprosthetic tibial fractures in UKA	Good
Houskamp et al. [39]	USA	Sawbone	Metal-backed fixed-bearing (Stryker)	In UKA, tibial resections beyond 5.82 mm increase the risk of periprosthetic fractures	Good

UKA unicompartmental knee arthroplasty; NR not reported

*Quality Appraisal for Cadaveric Studies (QUACS) Scale was used as a quality assessment tool