Pictured here is a large sacral decubitus with a large area of adjacent reddened skin questionably more consistent in appearance to imitation than cellulitis or pressure ulcers. The base of the ulcer has granulation tissue.
Paraplegics with pressure sores are subject to a multitude of associated complications including urinary tract infection leading to chronic renal failure, malnutrition, spasticity of the lower extremities, and, particularly with more proximal lesions, pulmonary insufficiency. More globally, an assessment of the patient’s social environment is important, as well as questions regarding tobacco and drug abuse.
The physical examination should include examining for the physical findings of inanition, spasticity, and also a direct probing of the decubitus to determine the magnitude of undermining.
Imaging can be done to detect osteomyelitis, but CT and MRI are non-specific. Erythrocyte sedimentation rate and white blood cell count will be elevated, but are not of clinical value. Objective nutritional assessment should be done by measuring albumin and pre-albumin. Social work and rehabilitation medicine input will be important in post-operative management.
Pathophysiology and Management
Pressure ulcers are caused by unrelieved, sustained pressure greater than capillary pressure, 15 Hg to 20 Hg, particularly if the external pressure is 2 times capillary pressure for greater than 2 hours. The weight of a body part places pressure on underlying bony prominences and produces necrosis of all overlying soft tissue, including skin. For example, in the sitting position, this may occur when weight is placed on the ischium. The magnitude of soft tissue necrosis is greater, from skin to bone. When viewed in cross section the zone of tissue necrosis will resemble an inverted cone, the tip at the skin. This pathologic anatomy has implications for debridement and closure.
Treatment plan goals should include the optimization of nutrition, treatment of co-morbidities, involvement of social work, and wound toilet and closure.
The redness of the surrounding skin may be secondary to the use of the vacuum assisted closure (VAC). Discontinuance of the VAC for 3 to 4 days may be of value. Nutrition is optimized and smoking cessation is mandated.
The general principles in surgical therapy is resection of the ulcer and bursa, excision of the osteomyelitic bone as judged by appearance at operation, provision of soft tissue cover and to design flaps as not to burn bridges for the possible occurrence of future ulcers.
Once those objectives are attained, intraoperative excision is followed by closure-reconstruction in a single stage. Excision of the bursa, including the floor over the bony sacrum, will expose the bone and excision of at least the superficial cortex will determine the depth, if any, of osteomyelitic bone, uncommon in the sacrum. Bilateral gluteal fasciocutaneous flaps with a V-Y design may be the best option for wound closure. Gluteal flaps are perfused by the superior and inferior gluteal arteries. A V-Y design would include the superior gluteal artery, a branch of the internal iliac, located at a point 5 cm inferior to the posterior superior iliac spine and 5 cm lateral on a line drawn from the spine to the greater trochanter. The base of the triangle of a V-Y flap is the sacral defect, the tip just medial to the greater trochanter. Incision of the fascia and not the muscle, the gluteus maximus, is all that is necessary, as well as the release of the attachments to the greater trochanter to allow for bilateral advancement. The lateral donor site can be closed in a V to Y fashion. A number of postoperative protocols exist. A common element in all of them is off-loading pressure through the use of specialized beds, physical therapy, and patient education.
Finally, all plastic surgeons should be aware of the importance of nursing plans to prevent ulcers in patients who are hospitalized. Nursing plans should include risk assessment with a risk assessment tool such as the Braden scale, appropriate skin care by the avoidance of shearing/moisture, frequent turning, and the use of air-loss beds in high-risk patients.