Limb Sparing Evaluation

The Penn Orthoplastic Limb Salvage Center looks at many factors to determine if your injured limb can be saved. Surgeons look at the severity of the trauma, the degree of bone fracture, how much damage there is to the soft tissue, and if there are lesions to the nerves and tendons.

To quantify the severity of your trauma, our experts will evaluate your case based on:

• Nerve Injury
• Ischemia (inadequate blood supply to part of the body)
• Soft tissue injury
• Skeletal injury
• Age
• Overall health/any comorbidities
• Psychological health

Several scoring systems are also in place to help physicians assess the severity of the trauma. They include:

• Mangled Extremity Severity Score-- a grading system for the early assessment of severely injured lower extremities
• Predictive Salvage Index (PSI)
• Limb Salvage Index (LSI)
• Mangled Extremity Syndrome Index (MESI)
• Hannover Fracture Scale

If our surgical team concludes that a reconstruction is possible and the limb can be saved, the next step will be to repair broken bones, reconnect arteries and veins, and cover wounds with flaps of tissue and grafts of tissue.

Microvascular surgery is a subspecialty of microsurgery and involves highly specialized skill. It is performed on tiny blood vessels ranging from three to five millimeters in diameter using an operating microscope and sutures small enough to pass through a human hair. In reconstructive surgery, microvascular surgeons are able to restore form and function by grafting soft tissue, repairing nerves, and repairing blood vessels.

Using an array of microsurgical tissue transfers, Penn surgeons will provide new living tissue for wound closure by taking living tissue from a donor site in your body and transferring it to fill the damaged area using microsurgical techniques. Using your own tissue is referred to as an autologous tissue transfer or free tissue transfer (free flaps), whereas an allograft flap is taken from a donor. 

Reconstruction includes tissue and muscle transfer, reconnecting or replacing major blood vessels, and nerve repairs with the goal of optimizing function.

Types of Flaps Used in Microvascular Surgery

In limb salvage cases, free flaps are used in a variety of ways to not only avoid amputation but to also optimize function. Free flaps can save a limb by closing a wound or filling in a defect.

The types of flaps used in microvascular surgery include:

• Free skin flap-- a flap made of healthy skin and tissue
• Free muscle flap-- a flap of muscle that is used primarily to provide a well-vascularized soft tissue that is relatively resistant to infection
• Free vascularized bone flap-- a live bone placed in the area of a defect where the blood supply is re-attached so the bone continues to receive the nutrients it needs to heal

  Types of free vascularized bone flaps include:

  • Fibular Flaps
  • Scapular Flaps
  • Iliac Crest Flaps
• Periosteal flap-- refers to the membrane several cell layers thick that covers almost all of every bone; flap that covers the outer surface of bone
• Allograft flaps-- a donor flap of skin, tissue, and/or muscle.

In cases of severe trauma, blood flow to affected tissues can be compromised resulting in necrosis--death of body tissue. Early treatment is critical if necrosis is suspected. Using microvascular techniques, the Penn team is able to restore blood flow to the affected area and avoid amputation or more severe debridement (removal of damaged tissue).

In patients with traumatic skeletal defects, bone infection, or tumor removal, there are several options for skeletal reconstruction including autologous bone grafts, vascularized bone transfer (pedicled or free), and the Ilizarov technique.

• Autologous bone graft is bone that is harvested from your own body, usually from the pelvis. This procedure is done to augment bone regeneration.
• Allograft bone replacement is harvested from a cadaver and used in bone regeneration.
• Vascularized bone transfer is a transfer of a bone or portion of a bone in which the circulation is maintained and allows it to be immediately established after surgery in the transplanted area.
• Ilizarov technique is an apparatus with a set of external fixators consisting of rings, rods and wires, all made of stainless steel that stimulates bone growth in non‐unions and regenerates bone lost due to infection.
• Complex Fracture Care uses advanced reconstruction techniques beyond standard plates, screws and rods, Penn uses 3D printing for custom fracture solutions.
• Limb Lengthening  For some patients, limb salvage requires the removal of bone resulting in limb length discrepancies. For these patients, as well as other individuals with limb length imbalance, the Penn Orthoplastic Limb Salvage Center provides the most advanced limb lengthening procedures. This treatment corrects height proportion, balances the patient’s gait, and addresses aesthetic concerns.

Penn surgeons will select the appropriate method as determined by the size and severity of your bone defect for a skeletal reconstruction.