Abtin Alvand

Purpose: Gastrocnemius flap coverage is a widely used technique for soft‐tissue reconstruction in complex revision total knee arthroplasty (rTKA) for periprosthetic joint infection (PJI). However, clinical outcomes following one‐stage and two‐stage revision strategies in this context are poorly defined. The purpose of this meta‐analysis was to synthesize, critically appraise, systematically review and compare reinfection rates and complication profiles between one‐ and two‐stage septic rTKA for PJI using a gastrocnemius flap for reconstruction. Methods: A systematic review and meta‐analysis based on the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines was conducted. MEDLINE, Embase, Cochrane Library and Web of Science were searched from inception to 6 April 2025 for studies on patients undergoing rTKA for PJI with soft tissue reconstruction using a gastrocnemius flap. Outcomes of interest included reinfection rates, any complications and flap‐related complications. A pooled meta‐analysis at group level was performed to compare interventions. Results: There were 11 studies reporting on 271 rTKAs involving gastrocnemius flap reconstruction for PJI that met inclusion criteria. Of these, 56 were one‐stage rTKAs, while 215 were two‐stage rTKAs. PJI eradication rate was 66.1% in the one‐stage group versus 54.4% in the two‐stage group. There were no statistically significant differences between groups for reinfection (odds ratio [OR]: 0.61; 95% confidence interval [CI]: 0.33–1.13; p = 0.12), any complications (OR: 1.59; 95% CI: 0.71–3.54; p = 0.26) or flap‐related complications (OR: 1.03; 95% CI: 0.43–2.47; p = 0.94). Conclusion: It was found that one‐stage and two‐stage rTKA using a gastrocnemius flap showed comparable rates of reinfection, any complication and flap‐related complication with the data available for this meta‐analysis. Findings suggest that one‐stage revision may be a viable treatment option for suitable patients. However, higher‐quality studies are warranted to identify potential true differences within this high‐risk group. Level of Evidence: Level IV.

Background: Managing medial compartment knee osteoarthritis (OA) with anterior cruciate ligament (ACL) deficiency, particularly in younger, active patients, remains challenging. Medial unicompartmental knee arthroplasty (UKA) combined with ACL reconstruction (ACLR) (UKACL) has gained interest, yet outcomes remain incompletely defined. This systematic review aims to evaluate the clinical effectiveness, implant survivorship, complications, and patient-reported outcomes after combined UKA and ACLR in end-stage medial OA with ACL deficiency. Methods: We systematically searched PubMed, Embase, Scopus, and Web of Science. Studies reporting outcomes of UKA performed with ACLR were included; case reports, technical notes, and biomechanical studies were excluded. Risk of bias was assessed with ROBINS-I V2. We extracted clinical outcomes, implant survival, complications, radiographic findings, and validated functional scores. Results: Fourteen studies comprising 353 patients met the inclusion criteria. Reported survivorship consistently exceeded 90% at 10 years. Ten revisions were reported, most commonly for lateral OA progression. Overall complication rate was 9.06% with no difference between mobile-bearing and fixed-bearing designs. Mobile-bearing implants had a slightly higher bearing dislocation risk, whereas fixed-bearing designs showed marginally higher polyethylene wear. Functional outcomes improved across studies. Conclusion: Combined UKA and ACLR appears effective for younger, active patients with isolated medial OA and ACL deficiency, yielding high survivorship and consistent functional gains. Given heterogeneity among studies, high-quality, long-term randomized trials are needed to refine patient and implant selection. Level of Evidence: Level IV , systematic review of nonrandomized studies. See Instructions for Authors for a complete description of levels of evidence.

Aims: Mixed clinical results have been reported following the use of lateral unicompartmental knee arthroplasty (UKA) in patients with isolated lateral compartment osteoarthritis (OA) of the knee. Although this procedure may be appropriate for use in about 10% of knees needing arthroplasty, it is only used in about 1%. The aim of this study was to determine the medium-term results for the Fixed Lateral Oxford (FLO) UKA.Methods: We report the clinical results and survival for 305 consecutive FLO UKAs implanted in 279 patients between July 2015 and August 2022. A total of 283 knees (93%) satisfied the recommended surgical indications. The mean age of the patients was 70.8 years (SD 11), their mean BMI was 28.4 kg/m² (SD 5.4), and 219 (72%) were female. Isolated lateral compartment OA was the indication for 298 operations (98%). The mean follow-up was 4.3 years (1 to 8). The Oxford Knee Score (OKS) was recorded pre- and postoperatively. The revision status of all knees was known.Results: There were four revisions (1%): two were conversions to a total knee arthroplasty (TKA) for instability and progressive OA and two had the addition of a medial UKA for medial compartment OA. Three other UKAs required a reoperation. At the last follow-up, the mean OKS was 40.9 (SD 7.8), a mean increase of 20 points from the preoperative score. The cumulative rate of survival with any reoperation, including revision, as the endpoint, at seven years, was 96% (95% CI 91 to 100), with revision as the endpoint was 98% (95% CI 94 to 100) and with revision to a TKA as the endpoint was 99% (95% CI 96 to 100). No revisions required revision TKA components. When those who underwent surgery for indications which were outside the recommended indications were excluded, there were only two revisions, both with the addition of a medial UKA for progressive OA, resulting in a seven-year cumulative survival with revision as the endpoint of 99% (95% CI 93 to 100).Conclusion: This study involved the largest published cohort of fixed-bearing lateral UKAs. The good clinical outcomes and medium-term survival of the FLO UKA, particularly in patients satisfying the recommended indications, suggest that it is an excellent alternative to TKA for the treatment of patients with isolated OA of the lateral compartment of the knee.Cite this article: Bone Joint J 2025;107-B(4):432–439.

Background: The purpose of this study was to investigate patient-relevant outcomes following first revision total knee arthroplasties (rTKAs) performed for different indications. Methods: This population-based cohort study utilized data from the United Kingdom National Joint Registry, Hospital Episode Statistics Admitted Patient Care, National Health Service Patient-Reported Outcome Measures, and the Civil Registrations of Death. Patients undergoing a first rTKA between January 1, 2009, and June 30, 2019, were included in our data set. Patient-relevant outcomes included implant survivorship (up to 11 years postoperatively), mortality and serious medical complications (up to 90 days postoperatively), and patient-reported outcome measures (at 6 months postoperatively). Results: A total of 24,540 first rTKAs were analyzed. The patient population was 54% female and 62% White, with a mean age at the first rTKA of 69 years. At 2 years postoperatively, the cumulative incidence of re-revision surgery ranged from 2.7% (95% confidence interval [CI], 1.9% to 3.4%) following rTKA for progressive arthritis to 16.3% (95% CI, 15.2% to 17.4%) following rTKA for infection. The mortality rate at 90 days was highest following rTKA for fracture (3.6% [95% CI, 2.5% to 5.1%]) and for infection (1.8% [95% CI, 1.5% to 2.2%]) but was <0.5% for other indications. The rate of serious medical complications requiring hospital admission within 90 days was highest for patients treated for fracture (21.8% [95% CI, 17.9% to 26.3%]) or infection (12.5% [95% CI, 11.2% to 13.9%]) and was lowest for those treated for progressive arthritis (4.3% [95% CI, 3.3% to 5.5%]). Patients who underwent rTKA for stiffness or unexplained pain had some of the poorest postoperative joint function (mean Oxford Knee Score, 24 and 25 points, respectively) and had the lowest proportion of responders (48% and 55%, respectively). Conclusions: This study found large differences in patient-relevant outcomes among different indications for first rTKA. The rate of complications was highest following rTKA for fracture or infection. Although rTKA resulted in large improvements in joint function for most patients, those who underwent surgery for stiffness and unexplained pain had worse outcomes. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background: The aim of this systematic review was to summarise the evidence for the clinical effectiveness of revision knee arthroplasty (rKA) compared to non-operative treatment for the management of patients with elective, aseptic causes for a failed knee arthroplasty. Methods: MEDLINE, Embase, AMED and PsychINFO were searched from inception to 1st December 2020 for studies on patients considering elective, aseptic rKA. Patient-relevant outcomes (PROs) were defined as implant survivorship, joint function, quality of life (QoL), complications and hospital admission impact. Results: No studies compared elective, aseptic rKA to non-operative management. Forty uncontrolled studies reported on PROs following elective, aseptic rKA (434434 rKA). Pooled estimates for implant survivorship were: 95.5% (95% CI 93.2–97.7%) at 1 year [seven studies (5524 rKA)], 90.8% (95% CI 87.6–94.0%) at 5 years [13 studies (5754 rKA)], 87.4% (95% CI 81.7–93.1%) at 10 years [nine studies (2188 rKA)], and 83.2% (95% CI 76.7–89.7%) at 15 years [two studies (452 rKA)]. Twelve studies (2382 rKA) reported joint function and/or QoL: all found large improvements from baseline to follow-up. Mortality rates were low (0.16% to 2% within 1 year) [four studies (353064 rKA)]. Post-operative complications were common (9.1 to 37.2% at 90 days). Conclusion: Higher-quality evidence is needed to support patients with decision-making in elective, aseptic rKA. This should include studies comparing operative and non-operative management. Implant survivorship following elective, aseptic rKA was ~ 96% at 1 year, ~ 91% at 5 years and ~ 87% at 10 years. Early complications were common after elective, aseptic rKA and the rates summarised here can be shared with patients during informed consent. Systematic review registration: PROSPERO CRD42020196922

Introduction Prosthetic joint infection (PJI) is a destructive complication of knee replacement surgery (KR). In two-stage revision a spacer is required to maintain limb length and alignment and provide a stable limb on which to mobilise. Spacers may be articulating or static with the gold standard spacer yet to be defined. The aims of this scoping review were to summarise the types of static spacer used to treat PJI after KR, their indications for use and early complication rates. Methods We conducted a scoping review based on the Joanna Briggs Institute’s “JBI Manual for Evidence Synthesis” Scoping review reported following Preferred Reporting Items for Systematic Review and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) checklist. MEDLINE, EMBASE and CINAHL were searched from 2005 to 2022 for studies on the use of static spacers for PJI after KR. Results 41 studies (1230 patients/knees) were identified describing 42 static spacer constructs. Twenty-three (23/42 [54.2%]) incorporated cement augmented with metalwork, while nineteen (19/42, [45.9%]) were made of cement alone. Spacers were most frequently anchored in the diaphysis (22/42, [53.3%]), particularly in the setting of extensive bone loss (mean AORI Type = F3/T3; 11/15 studies 78.3% diaphyseal anchoring). 7.1% (79 of 1117 knees) of static spacers had a complication requiring further surgery prior to planned second stage with the most common complication being infection (86.1%). Conclusions This study has summarised the large variety in static spacer constructs used for staged revision KR for PJI. Static spacers were associated with a high risk of complications and further work in this area is required to improve the quality of care in this vulnerable group.