Orthopedic Surgery

June 08, 2024

One indication for a visit to Norman S. Turner III, M.D., an orthopedic surgeon specializing in foot and ankle surgery at Mayo Clinic in Minnesota, is development of foot drop. A major cause of foot drop is significant knee or pelvis trauma, such as from motor vehicle crashes or serious surfboard or downhill ski accidents. This type of injury may damage the patient's peroneal nerve, resulting in loss of strength with holding the ankle up. Patients with this injury develop an altered, abnormal, high-stepping gait.

"We lift the ankle as we walk," says Dr. Turner. "But if you can't do that, you have a poor gait and trip over your toes."

Foot drop, which is typically unilateral, is an uncommon injury. It appears in a wide age range — from the teen years to age 80.

Foot drop's clinical pathway

Patients with trauma-related foot drop have several potential treatment options. These options depend on patients' level of injury and the joint decision-making of patients and their orthopedic surgeons. This condition usually follows a clinical pathway involving:

• Orthosis. Physicians generally initiate foot drop treatment with a brace, a conservative measure to improve the patient's gait. Dr. Turner says that patients often seek to determine if they are surgical candidates after using a brace for a time.

  "Most people want out of a brace," says Dr. Turner. "Although it may be simple to wear, they have to wear a large brace to make an impact on the gait. It is cumbersome and clumsy."

  He mentions that patients in their 20s and 30s particularly dislike using a brace due to the stigma.

  However, Dr. Turner believes that fully experiencing the challenges of foot drop and use of a brace for a period are necessary steps to ready patients for surgery.

  "Living with the foot drop first for a time is helpful to realize what the problem is," he says. "Over time, the patient sees that the gait problem and the brace are not ideal."

• Physical therapy (PT). PT can contribute to trauma-related foot drop treatment through improving range of motion, helping the ankle's ability to raise up past the neutral position.

  If a patient decides to pursue the Bridle procedure, PT also can strengthen the muscle the surgeon will transfer presurgically. Post-surgically, PT can train the posterior tibial tendon to function in a new manner. Dr. Turner notes that as patients undergo PT, they should be aware that some individuals have more musculoskeletal intelligence and ability to reach functional goals before others who have experienced similar surgery.

• Surgery with Bridle procedure. Dr. Turner considers patient decisions should be individualized about pursuing surgery with the Bridle procedure. Two crucial factors in this determination include the level of injury causing the foot drop and the patient's functional abilities. If a patient decides to undertake surgery, he seeks to ensure the patient has appropriate expectations.

  "The Bridle procedure doesn't help nerve pain — it just gets the patient out of the brace, so the ankle moves up and down," Dr. Turner says. "The surgery makes patients better, but not normal."

  Dr. Turner considers no longer needing a brace post-surgically a treatment goal for patients who undergo the Bridle procedure. Other key post-surgical goals include the patient returning to close to normal function for this tendon and regaining the ability to participate in preferred preinjury activities. Dr. Turner says his patients can ski, bike, swim and play basketball, for example, after healing from the Bridle procedure.

  Another important level-set for patients who have experienced tendon injury is that even post-surgically, they should expect to always have a stiffer ankle than individuals who have never experienced this injury, says Dr. Turner.

  After patients know what to expect from surgery, Dr. Turner will request scheduling them for the Bridle procedure. This surgery involves tendon harvest from the inside of the foot, then transferring that tendon to the top of the foot and connecting it with other tendons.

  "The way this works after surgery is that when the patient pulls up the foot, the bridle pulls the foot up straight," says Dr. Turner.

  Post-surgically, the surgeon protects the foot and ankle in a cast, followed by a boot, and then a brace. Patients must avoid weight-bearing activities for approximately eight weeks and protect the tendon during 6 to 12 months of healing.

Bridle procedure outcomes and patient satisfaction

Dr. Turner describes positive outcomes from the Bridle procedure as well as high patient satisfaction post-surgically. He points to research by Jeffrey E. Johnson, M.D., who completed an orthopedic surgery residency at Mayo Clinic in Minnesota and now practices at Washington University Orthopedics in St. Louis. Dr. Johnson's research team measured outcomes following surgery using the Bridle procedure for foot drop in 19 patients compared with 10 matched controls. This study's findings appeared in a 2015 Foot & Ankle International article.

In this study, preoperatively and two years postoperatively, the researchers administered radiographic foot alignment measurements and the Foot and Ankle Ability Measure for patients who had the Bridle procedure. At follow-up, the research team evaluated patients who had the Bridle procedure and controls for standing balance, ankle plantar flexion and dorsiflexion isokinetic strength. Also at follow-up, for the 19 patients who had the Bridle procedure, Dr. Johnson and colleagues administered questionnaires. The patients completed the Foot and Ankle Ability Measure, the American Orthopaedic Foot & Ankle Society Ankle-Hindfoot Scale, and the Stanmore system questionnaire.

The investigators found no changes in radiographic foot alignment. They also observed that measures of balance and strength did not return to typical, noninjured posterior tibial tendon functional levels post-surgically. Yet, all patients who had the Bridle procedure reported their surgical outcomes as good (seven patients) to excellent (12 patients) with 100% satisfaction. All patients indicated they would repeat the decision to have the surgery. For day-to-day activities, none of the patients studied required an orthosis.

Dr. Turner indicates that Mayo Clinic has seen similarly high patient satisfaction levels of more than 90% satisfaction after undergoing a Bridle procedure for trauma-related foot drop. He and colleagues welcome referrals to Mayo Clinic for evaluation for this procedure.

For more information

Johnson JE. Outcomes of the Bridle procedure for the treatment of foot drop. Foot & Ankle International. 2015;36:1287.

Refer a patient to Mayo Clinic.