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Knee perforator flap

In this case study, we explore the treatment and reconstruction of a burn wound on the left knee. The patient was referred to the outpatient department of Burn Center Beverwijk in the Netherlands three weeks after sustaining the burn injury. The use of an islanded perforator-based flap was employed for wound closure, providing both functional and aesthetic benefits. However, this technique requires specific knowledge, skills, and the use of a Doppler device.

Medical history

The patient, a 70-year-old individual, had suffered a burn injury to the left knee after prolonged contact with hot sauna furniture. The exact incident was not recalled, but it was believed that the patient collapsed due to dehydration and remained unconscious for approximately one hour. After being admitted to the intensive care unit (ICU) for two days to recover from heatstroke, a wound on the left knee remained. The patient experienced difficulty walking and severe pain. Other than the burn injury, the patient was in good health but had lost 8 kilograms of bodyweight since the ICU admission.

Physical examination

During the outpatient visit, the burn wound was observed on the anterior left knee. The eschar (dead tissue) was partially removed, revealing necrotic tissue. No signs of infection or pus were present. The affected area accounted for approximately 1% of the total body surface. The patient demonstrated slight flexion in the knee, and the patella tendon appeared intact. Due to recent weight loss, excess tissue was noted in the upper leg.

Conservative management

Since surgical debridement was necessary in this case, it was scheduled for the following week. In the meantime, the wound was dressed with silver sulfadiazine for comfort, and the patient's wife was instructed on how to perform wound dressings at home.


Several options were considered based on the characteristics of the wound following debridement. In this case, the likelihood of exposed bone and the patella tendon prompted the decision to employ a flap for wound closure. Due to excess tissue in the upper leg, a local fasciocutaneous flap design was chosen, specifically a perforator-based flap. Preoperatively, color Doppler sonography was conducted to identify the perforating arteries, aiding in the flap design. The surgery was performed under spinal anesthesia, and the necrotic area on the patella was removed (Photos 3 & 4). The perforator-based flap was then transposed and secured (Photos 5 & 6).

Postoperative care

The wound was dressed using synthetic, non-adhesive bandages, and a brace was provided to maintain leg extension for the first week. Crutches were utilized for initial mobility. After five days, the patient was discharged, and the undressed flap appeared viable.


Following the surgical intervention, the patient's progress and recovery were closely monitored. At the outpatient department, 15 days after the surgery, no signs of necrosis were observed, and the wounds had nearly healed. Importantly, the patient demonstrated an active flexion of the knee up to 60 degrees, indicating significant improvement (Photo 7).

Three weeks postoperatively, the wound had completely healed, and the patient's knee flexibility had further improved, allowing for a flexion of 90 degrees. At this stage, the non-absorbable sutures were safely removed, marking another milestone in the healing process (Photos 8 and 9).

By the two-month mark, the patient had regained the ability to walk and sit normally, reflecting the successful restoration of functionality. This remarkable progress demonstrated the effectiveness of the surgical intervention and the patient's commitment to rehabilitation.

Fast forward five years after the surgery, the patient and his wife remain extremely satisfied with the long-term outcome. He has successfully reintegrated various physical activities into his life, including cycling, rowing, and jogging. While working in the garden, he ensures extra comfort by using a pillow to rest his knees. Overall, the patient experiences no disability or limitations in daily life, exemplifying the positive impact of the surgical intervention on his quality of life.

This case underscores the remarkable potential for successful recovery and long-term outcomes in knee burn wound reconstruction. Through proper surgical management and diligent rehabilitation, individuals can regain mobility and lead fulfilling lives even after experiencing significant burn injuries to a major joint like the knee.

Lessons learned

The treatment and reconstruction of a burn wound on a major joint, such as the knee, require specialized care at a burn center. This case study highlights important lessons learned during the management of such injuries. Deep burn wounds necessitate the use of local flaps, specifically perforator-based flaps, to promote efficient healing and functional restoration. Skin grafts are not suitable for these cases as they cannot survive when placed on exposed bone. Additionally, the location of the burn on a joint underscores the need for mobile skin to ensure proper joint functionality. Well-vascularized flaps not only offer improved mobility but also have the potential to increase in surface area over time.

Lessons Learned:

  1. Referral Criteria for Joint Burn Wounds: When a burn involves a major joint, it is crucial to seek specialized care at a burn center, if possible. The complex nature of these injuries necessitates the expertise and resources available at such centers to achieve optimal outcomes.
  2. Utilizing Perforator-Based Flaps for Deep Burn Wounds: Deep burn wounds require a tailored approach, such as the use of local flaps like the perforator-based flap technique. This method ensures a faster and more successful recovery compared to skin grafts, which are inadequate for wounds involving exposed bone.
  3. Importance of Flap Selection for Joint Burns: Opting for a flap technique is particularly advantageous when the burn occurs on a joint. Mobile skin is essential for the proper functioning of joints, and well-vascularized flaps not only provide necessary mobility but also have the potential to increase in size over time, accommodating the joint's movement.

By applying these lessons, healthcare professionals can optimize outcomes in the treatment and reconstruction of burn wounds affecting major joints.

CASEKnee perforator flap