Outcome of tibialis posterior tendon transfer to middle cuneiform by interference screw technique for foot drop

Background: Foot drop is a common problem which compromises the quality of life and impairs activities of daily living. Walking becomes difficult with foot drop because the foot quickly hits the obstacles, or the knee has to be more flexed than usual when going up stairs. Transfer of the tibialis posterior tendon restores active dorsiflexion of the foot, while tenodesis prevents the foot from dropping. To this purpose, we explored the results of this technique in a small cohort of foot drop patients.Methods: Twenty-five patients with foot drop due to various causes such as tibial condyle fracture, fracture dislocation of the hip, post hip surgeries, late compartment syndrome and due to spinal aetiology by lumbar canal stenosis, post spinal surgeries due to discectomy and spondylolisthesis were included. Patients with post-traumatic arthritis of ankle, metabolic causes, poliomyelitis, sensory and motor neuropathy were excluded. Patients underwent anterior transposition of the tibialis posterior tendon (PTT) to the middle cuneiform through the interosseous membrane using tenodesis screw technique. The outcomes measured 2, 6 12 and 24 weeks postoperatively were a power of dorsiflexion, use of footwear to assess the dorsiflexion of the ankle in swing phase and at heel strike, hindfoot valgus patient satisfaction and activities of daily living.Results: The average age of the patients was 46±7.4 years. 18/25 (72%) had the 4+/5 power of dorsiflexion, 7/25 (28%) had 4-/5 power. 23/25 (92%) of patients use of footwear of certain types, suggesting that these patients improved from a high-stepping gait to a heel-toe gait. 18/25 (72%) patients were very satisfied, and 4/25 (16%) were happy, 3/25 (12%) patients were not satisfied. We found that 14/25 (56%) were having regular daily activity, and rational recreation and none of our patient had a severe limitation on functional assessment. All the 25 patients in our cohort exhibited dorsiflexion of the ankle in swing phase by 12 weeks post operatively.3/25 (12%) had hindfoot valgus postoperatively. None of our patients had wound complication at the insertion site. Conclusions: Tenodesis screw technique for insertion site fixation showed 72% result in restoring ankle function with a similar patient satisfaction and minimal complications