Distal femoral fractures comprise approximately 5% of all femoral fractures [1]. Non-operative management of these fractures is largely outdated due to the high risk of complications, including malunion, non-union, and joint stiffness [2]. With advancements in surgical techniques and implant design, operative fixation has become the preferred approach, though debate remains regarding the most effective implant choice. The use of implants like the condylar blade plate in distal femoral fractures has been associated with a high complication rate, while the introduction of locking plates has provided enhanced stability and improved clinical outcomes [3]. However, placing the condylar blade plate is technically challenging, requiring precise three-dimensional alignment; improper positioning of the chisel or plate can result in condylar malalignment [4].Locking plate technology allows for stable fixation with minimal soft tissue disruption, preserving blood supply around the fracture site. Unlike unlocked plates, locked plates do not rely on the screw-bone interface alone, which reduces the likelihood of construct failure, especially in osteoporotic or comminuted fractures [5].

The retrograde intramedullary nail (RIMN) has also demonstrated favorable outcomes, particularly for extra-articular distal femur fractures, due to reduced soft tissue trauma and preservation of the fracture hematoma [6,7]. Evidence supports using RIMN even in certain intra-articular fractures. For example, Heiney et al. achieved positive outcomes with nailing in AO type C1 intra-articular fractures [8], while Neubauer et al. also showed favorable results with this approach [9]. Studies by Saumya et al. and Garnavos et al. suggest that retrograde nailing with supplemental compression screws facilitates early weight-bearing and minimizes complications [10,11]. Warner et al. highlighted that retrograde nailing in intra-articular fractures, although effective, can present challenges such as iatrogenic fracture combination, inadequate articular fracture stabilization, and insufficient fixation, sometimes necessitating supplemental plate fixation [12].In femoral peri-prosthetic fractures, retrograde nailing is often preferred, although its use is limited by prosthetic design and the risk of extension deformities due to the posterior nail entry point [13].Despite extensive use of both implants for distal femoral fractures, there is no consensus on which is superior. The few comparative studies available have yielded inconsistent results. Consequently, this meta-analysis was conducted to evaluate the relative outcomes of locked plating versus retrograde intramedullary nailing in managing distal femoral fractures.

Search strategy This study was designed and executed in alignment with PRISMA guidelines [14]. A comprehensive search was conducted across electronic databases, including PubMed, Embase, Scopus, and Ovid Medline, from each database's inception through 2019-2023. The search was limited to articles published in English and used keywords such as “distal,” “femur,” “fracture,” “intramedullary fixation or plate or plating,” and “nail or nailing.” Additionally, the reference lists of included studies, original articles, and previous reviews were manually examined to identify further relevant studies for inclusion. InclusionCriteria • The study design was either a randomized controlled trial (RCT) or a comparative study (Level 1, 2, 3, or 4). • Participants were adult patients with distal femoral fractures, whether open or closed. • The study included at least two groups, one of which involved fixation with a locked plate and another with a retrograde nail for distal femoral fractures. • Outcome measures included one or more of the following: anterior knee pain, malunion, non-union, duration of surgery, implant failure, and infection. Exclusion Criteria • Included only elderly patients or focused exclusively on periprosthetic distal femoral fractures. • Employed condylar blade plates or angle blade plates. • Had incomplete data, limiting statistical analysis. • Were reviews, letters, or commentary articles. • Represented duplicated literature. • Were cadaveric studies or case reports. • Included fractures of other femoral regions. Study Selection The initial database search yielded 1920 studies, from which 603 duplicates were removed. The remaining 444 articles were screened, leading to the exclusion of 1476 studies based on title and abstract review. An additional three studies were excluded for not exclusively using locked plates or for lacking specific mention of their use [15,16,17]. One study focused solely on osteoporotic elderly patients, and another was a feasibility trial, both of which were excluded (18,19). Following a detailed review of titles, abstracts, and full texts of the shortlisted studies, six studies were deemed suitable for inclusion (8,10,20-23) [Tables 1 and 2]. Table 1: Search Methodology Database Search Date Search Query Results Google Scholar 14 July 2024 ((distal [All Fields] AND ("femur"[MeSH Terms] OR "femur"[All Fields]) AND ("fractures, bone"[MeSH Terms] OR ("fractures"[All Fields] AND "bone"[All Fields]) OR "bone fractures"[All Fields] OR "fracture"[All Fields])) AND English[lang]) 1680 PUBMED 14 July 2024 (distal[All Fields] AND ("femur"[MeSH Terms] OR "femur"[All Fields]) AND ("fractures, bone"[MeSH Terms] OR ("fractures"[All Fields] AND "bone"[All Fields]) OR "bone fractures"[All Fields] OR "fracture"[All Fields]) AND ("intramedullary fixation"[All Fields] OR ("nails"[MeSH Terms] OR "nails"[All Fields] OR "nail"[All Fields]) OR ("fracture fixation, intramedullary"[MeSH Terms] OR ("fracture"[All Fields] AND "fixation"[All Fields] AND "intramedullary"[All Fields]) OR "intramedullary fracture fixation"[All Fields] OR "nailing"[All Fields])) AND English[lang] 129 EMBASE 14 July 2024 distal AND femur AND fracture AND ('intramedullary fixation' OR nail OR 'intramedullary nailing') AND (plate OR plating) AND [english]/lim 111 Data Collection and Analysis Two independent reviewers conducted the screening of studies. The title of the current study served as a guide to assess articles that seemed suitable for inclusion, followed by a review of their abstracts. In cases where uncertainty arose during abstract screening, full-text articles were retrieved for further evaluation. Articles relevant to the research question were identified, and these shortlisted studies were included in the final review for analysis. Any selection disagreements between the two reviewers were resolved through discussions with additional co-authors to reach a consensus. Data extraction was recorded in a structured form, categorizing studies into two groups: Group 1—Retrograde Medullary Nail (RLN) and Group 2—Distal Locked Plating (DLP). The extracted data included information such as authors' names, publication year, demographic details (age, sex, number of patients), and complications (e.g., infection, malunion, anterior knee pain). For studies with missing information, the authors were contacted directly for clarification. Fig 1: PRISMA Flowchart of the studies selected for the current study Quality Assessment Two independent reviewers evaluated the methodological quality of all included clinical trials following Cochrane Collaboration guidelines. Key aspects assessed included random sequence generation, allocation concealment, blinding of outcome assessment, completeness of outcome data, selective reporting, and potential sources of other biases.