Resection Technique Does Affect Resection Symmetry and Thickness of the Patella During Total Knee Arthroplasty: A Prospective Randomized Trial

Patellar Resurfacing in Total Knee Arthroplasty, a Never-Ending Controversy; Case Report and Literature Review

Total knee arthroplasty (TKA) remains a lifesaving procedure for advanced gonarthrosis. However, patella resurfacing (PR) in TKA remains a controversial procedure, leading to extensive discussions amongst orthopedic surgeons, regarding its indications and results. Based on these premises, we present a clinical case of a 70-year-old Caucasian woman admitted for pain, swelling and limitation of left knee joint mobility. Her medical history records an Ahlback stage IV gonarthrosis with simultaneous bilateral TKA surgery performed in different hospital, when two NexGen cemented total prostheses were implanted with patellar resurfacing being performed only on the right side. Our clinical (American Knee Society Score, Lonner and Feller scales) and radiological evaluations (CT scan and Xray) revealed left patellar arthrosis and a slight lateral subluxation of the patella. The chosen treatment plan was revision surgery for PR and patellar prosthesis with a cemented patellar component, cross-linked polyethylene, no 32 NexGen model with 8.5 mm thickness. The immediate and distant postoperative evolution was favorable. Extensive literature review shows that, at present, PR remains at surgeon's discretion mainly based on his previous results. Therefore, we believe there is an imperative need to develop high quality studies based on accurate scientific evidence to universally establish valid guidelines for PR in TKA.

Patellar management during total knee arthroplasty: a review

The optimal management of the patella during total knee arthroplasty (TKA) remains controversial and surgeons tend to approach the patella with one of three general mindsets: always resurface the patella, never resurface the patella, or selectively resurface the patella based on specific patient or patellar criteria.

Studies comparing resurfacing and non-resurfacing of the patella during TKA have reported inconsistent and contradictory findings.

When resurfacing the patella is chosen, there are a number of available patellar component designs, materials, and techniques for cutting and fixation.

When patellar non-resurfacing is chosen, several alternatives are available, including patellar denervation, lateral retinacular release, and patelloplasty. Surgeons may choose to perform any of these alone, or together in some combination.

Prospective randomized studies are needed to better understand which patellar management techniques contribute to superior postoperative outcomes. Until then, this remains a controversial topic, and options for patellar management will need to be weighed on an individual basis per patient.

Cite this article: EFORT Open Rev 2021;6:861-871. DOI: 10.1302/2058-5241.6.200156

Onlay Patellar Resurfacing in a Posterior-Stabilized Total Knee Arthroplasty Increases Patellar Crepitus Complication: A Randomized, Controlled Trial

BACKGROUND

Patellar crepitus (PC) is a potentially problematic complication after total knee arthroplasty (TKA) more commonly occurring with a posterior-stabilized (PS) prosthesis. Patellar resurfacing has been reported to reduce PC complications; however, no study has compared the PC complication rates between 2 different resurfacing techniques, namely inlay and onlay.

METHODS

A prospective, randomized controlled trial was conducted to compare the PC complication between inlay and onlay patellar resurfacing techniques. A total of 222 patients who underwent unilateral TKA using a Legion PS Total Knee System were randomized into 2 groups. PC incidence, time of PC presentation, radiographic parameters associated with PC development, and clinical outcomes were evaluated at 3, 6, 9, 12, 18, and 24 months postoperatively.

RESULTS

PC occurred significantly more in the onlay group (17.9% vs 6.5%, P = .009). Time of PC presentation in both groups was not different. Anterior knee pain was found in 11.5% of PC patients, and none required any surgical procedure. Postoperative radiographic parameters, range of motion, Knee Society score, Oxford score, patellar score, incidence and intensity of anterior knee pain, and visual analog scale of overall knee pain were not significantly different between the 2 groups during the follow-up period.

CONCLUSION

To reduce the chance of PC development, we suggest an inlay patellar resurfacing technique during PS-TKA with this knee system.

Management of the Patella During Total Knee Arthroplasty

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The optimal management of the patella during total knee arthroplasty (TKA) remains a controversial topic with no consensus.

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Patellar management techniques during TKA include patellar retention or resurfacing with or without patellaplasty, as well as circumferential denervation and partial lateral facetectomy (PLF).

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Special considerations such as patient age, etiology of disease, implant design, and surgeon preference should be accounted for when determining optimal management.

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We recommend that most patellae be circumferentially denervated, regardless of whether they are resurfaced, as the potential benefits outweigh the small associated risks.

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Evidence demonstrates improved functional outcomes with the addition of PLF to nonresurfaced patellae. There is currently a paucity of evidence of this technique with respect to resurfaced patellae.

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Patellar resurfacing adds additional costs and health-care resources that should be considered in the decision-making process.

The evolution of patellofemoral prosthetic design in total knee arthroplasty: how far have we come?

Total knee arthroplasty (TKA) has evolved into a successful, cost-effective treatment for end-stage knee arthrosis.The patellofemoral articulation in TKA has largely been ignored during its development despite being an important determinant of outcome.New technologies still need further development to incorporate the patella in TKA surgical planning and operative technique.Alternative approaches to alignment in TKA will have a secondary impact on patellofemoral mechanics and possibly future implant designs.Technologies that assist with precise implant positioning may alter our understanding and overall practice of TKA. Cite this article: EFORT Open Rev 2019;4:503-512. DOI: 10.1302/2058-5241.4.180094.

Clinical and radiologic outcomes of two patellar resection techniques during total knee arthroplasty: a prospective randomized controlled study

PURPOSE

A cutting guide technique for patella resurfacing in total knee arthroplasty was expected to result in less patellofemoral syndromes. The aim of this study was to identify differences in the patellofemoral function, clinical outcomes, and radiographic parameters between the freehand and cutting guide patellar resection techniques in patients undergoing total knee arthroplasty.

METHODS

A prospective randomized controlled trial was conducted. The study was registered in a public trials registry (International Standard Randomized Trial No. NCT02268097). One-hundred total knee arthroplasties in 100 patients were randomly allocated into one of the two groups, and their results were followed for a mean of 28 months (range, 18 to 38 months) in a double-blind (both patient and evaluator), prospective study. Evaluation was performed by an independent observer using patellofemoral functional capacity, the Knee Society clinical rating system, the Western Ontario and McMaster Universities Osteoarthritis Indices, and radiographic examination.

RESULTS

In total, 14% of the patients were lost to follow-up. There was no difference in the incidence of anterior knee pain between the two groups. No patients received or required revisions. There was a significant difference in the outliers of lateral patellar tilt between the freehand and cutting guide groups (> 10°) (p = 0.036); however, the mean value of lateral patellar tilt did not differ significantly. There were no differences between groups with respect to the 30 seconds stair climbing test, complications, the Knee Society clinical rating system, the Western Ontario and McMaster Universities Osteoarthritis Indices, patient satisfaction, physical examination, hip-knee-ankle angle, lateral patellar displacement, or the Insall-Salvati ratio. Meanwhile, gender, age, weight, height, body mass index, pre-operative Knee Society scores, and pre-operative range of motion were not found to be related to the development of anterior knee pain.

CONCLUSIONS

Cutting guide technique group did not yield lower incidence of anterior knee pain. More outliers of lateral patellar tilt were observed in the freehand technique group. Overall, all patients in both groups had identical results in terms of patellofemoral functional capacity, clinical outcomes, and other radiographic results.