Patient-specific instrumentation in total knee arthroplasty

ABSTRACT

Introduction: Total knee arthroplasty (TKA) is one of the most commonly performed orthopedic procedures. During the past decade, patient-specific instrumentation (PSI) has been commercially introduced in order to simplify and make TKA surgery more effective, precise and efficient than conventional mechanical instrumentation (CI) and computer-assisted surgery (CAS). Nevertheless, there are critical arguments against PSI for routine use. The aim of the current manuscript is to describe advantages and limitations of PSI for primary TKA.

Areas covered: By means of a description of the available literature different aspects are discussed (accuracy, clinical and functional outcomes, operative time, blood loss, efficiency and costs).

Expert opinion: Most publications do not claim a significant increase in PSI accuracy over CI, but they also do not postulate PSIs accuracy is worse either. Regarding clinical aspects, PSI did not appear to give any advantage over standard techniques although, equally, it did not appear to show any disadvantages. PSI seems to reduce operative time, could reduce perioperative blood loss and provides logistical benefits in the operation room. Further studies will be required to more thoroughly assess all the advantages and disadvantages of this promising technology as an alternative to CI and CAS.

KEYWORDS:

• Patient-specific instrumentation (PSI)
• total knee arthroplasty (TKA)
• total knee replacement (TKR)
• knee

Article highlights

• The limited accuracy of conventional mechanical surgical technique (CI) has provided an incentive for the development of newer technologies to improve the accuracy of surgery whilst also increasing operative efficiency. Computer-assisted surgery (CAS) and patient-specific instrumentation (PSI) were introduced.

• Although the importance of a neutral mechanical axis to the success of TKA has been questioned, a neutral mechanical axis still remains a reasonable target for most surgeons performing TKA. Most publications do not claim a statistically significant increase in PSI accuracy over CI but, in general terms, they do not claim that accuracy with PSI is worse either.

• Regarding clinical aspects, PSI did not appear to give any advantages over standard techniques although, equally, it did not appear to show any disadvantage. PSI seems to reduce operative time, could reduce perioperative blood loss and provides logistical advantages in the operation room.

• Further studies will be required to more thoroughly assess all the advantages and disadvantages of this technology as an alternative to CI and CAS.

Authors’ information

VL, FM and FS are specialists in Orthopaedic Surgery and Musculoskeletal Traumatology. ML is specialist in Computer Engineering in the field of Information and Communications Technology.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Figures and tables authorship

The figures and tables are original and have not previously been published.

Additional information

Funding

This paper was not funded.