Patient outcomes in Anteromedial osteoarthritis patients over 80 years old undergoing Oxford Unicompartmental knee Arthroplasty in China

Restoration of constitutional alignment optimizes outcomes of computer navigated total knee arthroplasty: a prospective randomized controlled trial

PURPOSE

The value of computer navigation in total knee arthroplasty (TKA) for arthritic knees continues to be debated. The purpose of this study was to evaluate the value of navigated TKA associated with updated alignment philosophy.

METHODS

This prospective randomized controlled trial enrolled 38 consecutive patients (76 knees) and were randomly assigned to both groups. The demographic data and perioperative data were recorded. The coronal plane alignment of the knee (CPAK) classification was used to classify knee alignment phenotypes. Radiographic outcomes were measured and subgroup analysis was further performed. Clinical outcomes were evaluated using patient-reported outcome measures (PROMs). Surgery-related complications were recorded.

RESULTS

The distribution of CPAK phenotypes following constitutional aligned TKA was equivalent to the native cohort, whereas the mechanical aligned TKA dramatically altered the phenotype distribution from type I and type II to type V and type IV. Final implant positioning was different between groups, with constitutional aligned TKA having larger cTCA (P = .004), joint line obliquity (P = .006), joint line distance (P = .033) and smaller sFCA (P = .013). Subgroup analysis showed higher actual accuracy of component positioning was achieved in navigated TKA, especially in knees with deformity of > 10° (P < .05). Patients reported higher HSS score at three months postoperatively in constitutional aligned group (P = .002). One patient in navigated group suffered femoral pin site fracture caused by a minor trauma.

CONCLUSION

Computer navigated TKA allows for restoration of constitutional alignment and minimizes soft tissue release, which when compared to mechanical alignment may be associated with superior early outcomes.

Debridement, Antibiotics, and Implant Retention for an Early Periprosthetic Infection After Unicompartmental Knee Arthroplasty: A Technical Note

Early periprosthetic joint infection in unicompartmental knee arthroplasty (UKA) is shown to have a detrimental effect on the success of UKA surgery not only because of the sequences of the infection but also due to the other healthy lateral compartment. It is well known that Oxford meniscal bearing UKA is a very precise procedure that the use of any excessive force may have an injurious effect on the future prosthesis stability with a higher risk of bearing dislocation. This technical note aims at describing how to deal with a case of early periprosthetic joint infection in a female patient who underwent debridement, wash, implant retention and change of the mobile bearing insert including the demonstration of a difficult step during this procedure.

Octogenarians Undergoing Medial Unicompartmental Knee Arthroplasty Have Similar Patient-Reported Outcomes as Their Younger Counterparts

BACKGROUND

As a procedure with lower surgical morbidity, unicompartmental knee arthroplasty (UKA) may present a practical solution for elderly patients with unicompartmental arthritis. However, few studies have analyzed the results of UKA in the extreme elderly. This study compared the functional and perioperative outcomes between octogenarians and age-appropriate controls undergoing UKA.

METHODS

Prospectively collected data of 44 patients aged ≥80 years who underwent unilateral UKA were analyzed. Each octogenarian was matched 1:3 with 132 patients aged 65-74 years using propensity scores adjusting for gender, body mass index, Charlson comorbidity index, and preoperative scores. Knee Injury and Osteoarthritis Outcome Score for Joint Replacement and Short Form-12 were collected preoperatively and 2 years postoperatively. Complications, reoperations, readmissions, and unplanned visits were recorded up to 1 year postoperatively.

RESULTS

The mean age was 70.0 ± 2.7 years in the control group and 83.0 ± 3.0 years in the octogenarian group (P < .001). The percentage of outpatient procedures was comparable (control 50.0%; octogenarian 45.5%; P = .601). With the exception of poorer Short Form-12 physical scores in octogenarians at 2 years (39.4 ± 14.1 vs 44.9 ± 9.2, P = .028), there was no difference in final postoperative scores or improvement in scores between the groups. The rate of complications, reoperations, readmissions, and emergency room visits was also similar. The five-year survivorship was 97% in the control group and 93% in the octogenarian group (P = .148).

CONCLUSION

Octogenarians undergoing UKA can experience clinical outcomes that are similar to those of their younger counterparts. The clinical trajectory outlined may help clinicians provide valuable prognostic information to elderly patients and guide preoperative counseling.

Excellent outcomes with Oxford Uni-compartmental knee arthroplasty in anteromedial osteoarthritis patients (≤60 years) at mid-term follow-up

Background

The use of Oxford uni-compartmental knee arthroplasty (UKA) has rapidly increased worldwide,however,the relevance of younger patients for postoperative function after Oxford UKA remains unclear. The main purpose of our study is to clarify the effectivemess of Oxford UKA in the younger Chinese patients with anteromedial osteoarthritis (AMOA).

Methods

We retrospectively enrolled 252 consecutive patients who underwent Oxford UKA for AMOA with a minimum follow-up of 5 years between March 2013 and December 2016. The patients were divided into the younger (≤60 years) and elderly (> 60 years) age groups. The demographic data and surgery variables were recorded and compared. Patient satisfaction grade, range of motion (ROM), Oxford knee score (OKS), Hospital for Special Surgery (HSS) score, Western Ontario and McMaster (WOMAC) Universities Osteoarthritis Index score and postoperative complications were recorded. The 5-year survival of the implants were also compared with TKA revision as the endpoint.

Results

A total of 252 consecutive patients were recruited, including 96 aged 60 years or less and 156 aged over 60 years. The mean follow-up duration in the younger and elderly groups were 73.6 months (SD,standard deviation, 4.1) and 74.7 months (SD 6.2) respectively. Patient satisfaction rate was high in both groups (P = 0.805). Furthermore, no significant differences were observed in postoperative ROM(P = 0.299), OKS(P = 0.117), HSS(P = 0.357) and WOMAC scores(P = 0.151) between the younger and elderly groups (P>0.05). However, the incidence of joint stiffness (P = 0.033) and delayed wound dehiscence (P = 0.026) were significantly different between both groups. Five-year implant survival without revision were also similar in both groups (96.9% vs 97.4%, P = 0.871), and that for the entire cohort was 97.2% (95% CI 95.4–99.6).

Conclusion

Oxford UKA for AMOA demonstrated favorable results in younger patients aged ≤60 years at a minimum 5-year follow-up in terms of patient satisfaction, functional outcomes, implant survival and postoperative complications. Therefore, younger patients might not be considered as an absolute contraindication to Oxford UKA.

Using MRI Measurement to Improve Accuracy of Femoral Component Sizing in Oxford Unicompartmental Knee Arthroplasty

Unicompartmental knee arthroplasty (UKA) can achieve better kinematics and faster recovery than total knee arthroplasty. The Phase III Oxford UKA system has five sizes of femoral components to approximate the normal knee geometry. However, these different sizes may also induce problems, such as the misselection of component size. Different criteria have been proposed to predict the ideal size preoperatively. However, no single method can be applied universally. Therefore, this study aimed to develop a preoperative measurement using knee magnetic resonance imaging (MRI) to predict femoral component size. A total of 68 patients who underwent UKA were investigated from June 2019 to April 2020. 16 knees using a different MRI protocol were excluded. We developed an MRI measurement method to determine femoral size instead of gender- and height-based methods. The accuracy of different methods was compared using postoperative true lateral view radiographs. Three different kinds of gender- and height-based criteria, preoperative templating and intraoperative spoon measurement were compared. The accuracy of MRI measurement was 90.3%. Therefore, a significant difference was found between MRI measurements and all other methods, such as templating or gender- and height-based methods. In conclusion, the MRI measurement method can be concluded to accurately predict femoral component size in UKA. This method could be used regardless of different ethnic groups, individual knee geometry, or soft tissue tension.

Clinical effect of warm needle penetration in treating knee osteoarthritis

OBJECTIVE

Our aim was to explore the clinical effect of warm needle penetration in treating knee osteoarthritis.

METHODS

We randomly divided 118 patients with knee osteoarthritis into the observation group (n=59) and the control group (n=59). The observation group was treated with warm needle penetration combined with western medicine therapy, and the control group was only given western medicine therapy. The clinical effective rate, Visual analogue scale pain score, knee joint score, Western Ontario and McMaster Universities osteoarthritis index and subjective satisfaction were observed and compared between the two groups.

RESULTS

The clinical effective rate, knee joint score and subjective satisfaction rate were higher (all P<0.05), while the Visual analogue scale pain score and Western Ontario and McMaster Universities osteoarthritis indices score were lower in the observation group than in the control group (both P<0.05).

CONCLUSION

Warm needle penetration can ameliorate the efficiency of treatment, reduce pain, and improve the range of knee joint motion and subjective satisfaction of patients with knee osteoarthritis.