Risk Factors for Patellar Clunk or Crepitation after Primary Total Knee Arthroplasty: A Systematic Review and Meta-analysis

The Perioperative Resource Use and Effectiveness of Patellofemoral Arthroplasty Versus Total Knee Arthroplasty: A Meta-Analysis

OBJECTIVE

Patellofemoral osteoarthritis (PFOA) is a common condition that significantly affects quality of life. With advancements in modern patellofemoral arthroplasty (PFA) prostheses, a growing number of surgeons are opting for PFA to treat isolated PFOA. This meta-analysis aimed to compare the perioperative resource use and therapeutic outcomes of PFA versus total knee arthroplasty (TKA) in patients with isolated PFOA.

METHODS

A literature search was conducted in PubMed, EMBASE, the Cochrane Library, and the Web of Science until November 2024. The included studies provided direct comparisons of perioperative resource use (surgical time, blood loss, and length of stay) and postoperative outcomes (patient-reported outcome measures [PROMs], quality of life, and patient satisfaction) between modern PFA and TKA in patients with isolated PFOA. The Cochrane risk of bias assessment tool was applied to randomized controlled trials, and the modified Newcastle-Ottawa Scale was used for observational studies to evaluate methodological quality and risk of bias. Data was extracted from eligible studies and combined to calculate the mean difference (MD) or pooled relative risk with a 95% confidence interval (CI).

RESULTS

We included eight eligible studies with a mean follow-up duration of 2-10 years. Compared with TKA, modern PFA demonstrated significantly shorter surgical times (MD = -13.67 min; 95% CI: -20.47 to -6.86) and reduced perioperative blood loss. However, no significant difference was observed in hospital length of stay. Regarding PROMs, PFA showed superior functional outcomes on the Oxford Knee Score (OKS) within 2 years postoperatively (MD = -2.02; 95% CI: -3.77 to -0.26). No significant differences were found between PFA and TKA at 12-month follow-up for the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function score (MD = -5.68; 95% CI: -21.54 to 10.18) or total WOMAC score (MD = -6.65; 95% CI: -30.00 to 16.70). Similarly, at 24-month follow-up, no differences were observed in the University of California, Los Angeles activity score (MD = -0.02; 95% CI: -1.79 to 1.75) or final OKS (MD = -1.09; 95% CI: -6.31 to 4.14). Quality of life and patient satisfaction remained comparable between the two procedures throughout the first 2 years and final follow-up.

CONCLUSIONS

PFA demonstrates comparable efficacy to TKA in isolated PFOA, with superior early functional recovery within the first 2 years post-surgery, shorter surgical duration, and reduced blood loss. These findings suggest PFA may be a resource-efficient alternative for eligible patients.

The prevalence and risk factors for peripheral nerve injury following arthroplasty: a systematic review and meta-analysis

OBJECTIVE

To assess the prevalence and identify the risk factors for peripheral nerve injury (PNI) following arthroplasty through a systematic review and meta-analysis.

METHODS

PubMed, Embase, and the Cochrane Library were searched for observational studies investigating the prevalence and risk factors for PNI following arthroplasty. Prevalence data for PNI following arthroplasty were extracted and pooled using a random-effects model, with results presented as pooled prevalence with 95% CI. ORs and 95% CIs for identified risk factors were calculated. Subgroup analyses were conducted based on age, study type, sample size, arthroplasty site, region, and others. Publication bias was assessed using funnel plots and Egger's test, and sensitivity analyses were performed.

RESULTS

After screening, a total of 21 studies were included in the meta-analysis. The pooled prevalence of PNI was 0.7% (95% CI: 0.006-0.009) with significant heterogeneity (I² = 99%). The prevalence of PNI following arthroplasty was found to be more likely as a result of several identified factors, including spinal conditions (ORs = 2.269, 95% CI 1.625-3.170), postoperative anemia (ORs = 1.370, 95% CI 1.149-1.633), mechanical complications (ORs = 1.791, 95% CI 1.118-2.868) and hypothyroidism (ORs = 1.189, 95% CI 1.054-1.341).

CONCLUSIONS

The pooled prevalence of PNI was approximately 0.7%. Furthermore, we identified potential risk factors for PNI following arthroplasty, including spinal conditions, postoperative anemia, mechanical complications, and hypothyroidism. Our findings emphasize the importance of recognizing these risk factors in the perioperative management of arthroplasty patients.

Synovium removal from the articular side of the quadriceps tendon around the superior pole of patella reduces the crepitus after total knee arthroplasty

PURPOSE

The purpose of this study was to investigate whether synovium removal from the articular side of the quadriceps tendon around the superior pole of the patella after total knee arthroplasty (TKA) reduced the incidence of patellar crepitus (PC) or not.

METHODS

We retrospectively reviewed 134 consecutive patients who underwent primary posterior stabilized (PS)-TKA by one surgeon from 2010 to 2013. Sixty-seven patients performed without touching synovium at superior pole of patella and 67 patients performed with removing all synovium from superior pole of patella were compared; none had patellar resurfacing. Patients were followed up two and six weeks, three, six and 12 months and annually thereafter. The primary outcome was the incidence of PC, detected during follow-up, and was graded as absent (0), fine (1), or coarse (2).

RESULTS

At one year of follow-up, the synovial removal (SR) group had a significant lower rate of PC compared to the synovial preserved (SP) group: 15/67 (22%) vs 34/67 (51%), adjusted odds ratio = 0.29, 95% confidence interval (CI) = 0.14 to 0.64, P = 0.002. All PC in SR group were grade 1 while four knees in SP group were grade 2. Mean PC onset was eight months after surgery (range 1.5 to 12, P = 0.78) in both groups.

CONCLUSION

Removal of the synovium from the articular side of the quadriceps tendon around the superior pole of patellar reduced the incidence of PC after primary PS-TKA without patellar resurfacing. This is a promising technique and might enlighten surgeons to reduce the noise and improve patient satisfaction after total knee replacement.