The posttraumatic knee: preoperative workup, imaging, and planning

Preoperative planning is crucial for all surgeons performing knee arthroplasty, especially in patients with a posttraumatic knee injury. Posttraumatic osteoarthritis (PTOA) is the third most common indication for total knee arthroplasty (TKA) after rheumatoid arthritis and primary osteoarthritis (OA), and accounts for 12% of all knee OA [1-3]. Patients with PTOA present unique challenges for arthroplasty surgeons secondary to possible intraarticular and/or extraarticular deformities, prior surgical incisions, hardware around the knee, and frequently diminished range of motion (ROM). In patients with more severe prior injuries, a compromised extensor mechanism, insufficient soft-tissue envelope, and/or an unresolved history of infection can complicate or may even prohibit a successful primary TKA. As such, the goal of this article is to review how to perform a thorough preoperative plan and evaluation in patients presenting with a posttraumatic knee, specifically focusing on the clinical history, key elements of the physical examination, and radiographic findings. All these aspects will help to determine whether an individual patient should proceed with a primary total knee arthroplasty, should proceed with a corrective osteotomy prior to primary TKA, or is not an arthroplasty candidate.

Brian P Chalmers

Hospital for Special Surgery
New York, USA

Managing posttraumatic osteoarthritis through nonoperative therapies

As with any patient presenting with knee pain from OA, the first-line approach in managing patients with PTOA is nonoperative. The mainstays of nonoperative management consist of activity modification, weight loss, nonsteroidal antiinflammatory drugs (NSAIDs), and acetaminophen [4]. Intraarticular injections of corticosteroid or viscosupplementation are also options [5, 6]; however, there is increasing evidence of the low cost-effectiveness of viscosupplementation for the treatment of end-stage knee OA [7]. Injections of stem cells and platelet-rich plasma (PRP) is currently in the experimental phase for the treatment of OA and is not generally recommended outside of well-designed research studies [8-10]. Further details about the benefits and limitations of these treatments are displayed in Table 1. When patients have tried many of these modalities but are still having significant pain and dysfunction that considerably affects their quality of life and daily activities, knee arthroplasty is an option.

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  • Preoperative workup: getting to know "a difficult knee"
  • Clinical history
  • Physical examination
  • Imaging and further workup
  • Evaluation for infection
  • Decision for the patient
  • Deformity correction, then primary TKA
  • Proceed with primary TKA
  • Primary TKA generally contraindicated

Part 2 | Corrective osteotomy

Part 3 | Techniques and implants

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Contributing experts

This series of articles was created with the support of the following specialists (in alphabetical order):

Friedrich Boettner

Hospital for Special Surgery
New York, USA

Brian P Chalmers

Hospital for Special Surgery
New York, USA

Austin T Fragomen

Hospital for Special Surgery
New York, USA

The authors thank Antia Rodriguez-Villalon and Laura Kehoe, medical writers at AO Innovation Translation Center, Switzerland, for contributing to the writing and editing of the articles.


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