What is the appropriate management approach for a non-displaced periprosthetic fracture of the right lateral femoral condyle with associated large lipohemarthrosis?

Management of Non-Displaced Periprosthetic Fracture of the Right Lateral Femoral Condyle with Large Lipohemarthrosis

For a non-displaced periprosthetic fracture of the lateral femoral condyle with lipohemarthrosis, initial conservative management with protected weight-bearing is the appropriate approach, reserving surgical fixation for fractures that displace or fail to heal. 1

Initial Management Strategy

Conservative Treatment Protocol

• Implement immediate non-weight bearing or touch-down weight-bearing for 6-8 weeks, as undisplaced periprosthetic fractures can successfully unite with conservative management 1
• Monitor the fracture closely with serial radiographs every 2-4 weeks to detect any displacement that would necessitate surgical intervention 1
• The presence of lipohemarthrosis (fat in the joint from marrow) confirms an intra-articular fracture but does not mandate surgery if the fracture remains non-displaced 1

Pain Management

• Administer regular paracetamol throughout the treatment period as the foundation of analgesia 2
• Use opioids cautiously, particularly in elderly patients or those with renal dysfunction, reducing both dose and frequency by half 2
• Avoid NSAIDs entirely if the patient has any degree of renal dysfunction, as they are contraindicated in this population 2

Thromboprophylaxis

• Prescribe fondaparinux or low molecular weight heparin, administered between 18:00-20:00 hours to minimize bleeding risk 2
• Apply thromboembolism stockings or intermittent compression devices 2
• Early mobilization (even non-weight bearing) is the most effective DVT prevention, so begin range-of-motion exercises immediately 2

Surgical Intervention Criteria

Indications for Operative Management

If the fracture displaces or fails to unite after 3-4 months of conservative treatment, surgical fixation becomes necessary 1

For displaced periprosthetic distal femoral fractures, use a lateral locking plate (>10 holes) with minimally invasive technique 3

Surgical Technique (If Required)

• Use the Less Invasive Stabilization System (LISS) or similar lateral locking plate for periprosthetic distal femur fractures 4
• Place the plate percutaneously with locked fixed-angle screws to avoid disturbing the prosthesis 4
• For fractures with intra-articular displacement, use an anterolateral parapatellar approach to achieve anatomic reduction of the condyles first 4
• Fix articular fragments with Kirschner wires before applying the lateral plate 4
• Ensure adequate working length with longer plates (>10 holes) to distribute stress and improve healing 3

Perioperative Considerations (If Surgery Required)

Monitoring Requirements

• Use central venous pressure (CVP) monitoring for patients undergoing periprosthetic fracture surgery, as these procedures carry higher risk 5
• Consider invasive blood pressure monitoring for patients with cardiac comorbidities 5
• Maintain core temperature monitoring and active warming strategies throughout surgery 2

Infection Prevention

• Administer prophylactic antibiotics within one hour of skin incision per hospital protocols 2
• Minimize soft-tissue dissection to preserve blood supply and reduce infection risk 3

Bone Cement Implantation Syndrome Prevention

If revision surgery is required, be aware that BCIS can occur with prosthesis manipulation 6

• Increase inspired oxygen concentration during any cement work or prosthesis manipulation 6
• Maintain adequate intravascular volume with fluid resuscitation 6
• Have vasoactive/inotropic support immediately available 6

Rehabilitation Protocol

Conservative Management Timeline

• Non-weight bearing or touch-down weight-bearing for 6-8 weeks based on serial radiographic evidence of healing 4
• Begin immediate range-of-motion exercises for the knee to prevent stiffness, even during the non-weight bearing period 4
• Progress to partial weight-bearing at 6-8 weeks if radiographs show callus formation 4
• Advance to full weight-bearing only after radiographic union is confirmed 4

Post-Surgical Timeline (If Required)

• Begin range-of-motion exercises on postoperative day 2 4
• Protected weight-bearing for 6 weeks, then advance based on radiographic healing 3
• Mean time to union is 15 months for periprosthetic fractures, so maintain close follow-up 7

Critical Pitfalls to Avoid

Common Errors

• Do not assume all non-displaced fractures will remain stable—31% of periprosthetic fractures develop complications requiring reoperation 7
• Avoid premature weight-bearing, as this can lead to displacement and necessitate surgical intervention 1
• Do not use codeine for pain management, as it causes constipation, nausea, and cognitive dysfunction without superior analgesia 2
• Recognize that varus collapse can occur even with surgical fixation, but may still result in acceptable functional outcomes if managed conservatively 8

Monitoring for Failure

• Watch for increasing pain, inability to perform range-of-motion exercises, or radiographic evidence of displacement 1
• If fracture displacement occurs, convert immediately to surgical fixation rather than continuing conservative management 1
• Monitor for infection throughout recovery, as 6 of 11 reoperations in one series were for infection management 7