Gait Analysis During Level and Uphill Walking After Lengthening Osteotomy of the Lateral Column
Condition: Osteotomy; Lengthening; Leg
Study type: Observational

Summary: 
      A common surgical treatment for posterior tibial tendon dysfunction (and the resulting flat
      foot) is the correction through a calcaneal lengthening osteotomy of the lateral column
      (LLC). Clinical studies showed pain relief and functional improvements through different
      scores. However, according to clinical experience, some patients complain about a limited
      ankle dorsiflexion after LLC surgery. Several joints of the foot (talocrural, subtalar,
      talonavicular, calcaneocuboid) contribute to the overall range of motion in foot
      plantarflexion/dorsiflexion and pronation/supination. Changes in the range of motion in one
      joint can affect all the other joints. For instance, it was shown that a fusion of the
      talonavicular joint removes most of the residual hindfoot motion in
      plantarflexion/dorsiflexion and pronation/supination. Because the lengthening of the lateral
      column presumably decreases the mobility of the medial column and thus of the talonavicular
      joint, this surgery can influence the range of motion of the other joints, and hence
      contribute to the reported decreased ankle dorsiflexion motion.

      Patients after LLC have less plantarflexion of the first metatarsal throughout stance of
      level walking and less inversion of the hindfoot during push-off compared to healthy
      subjects. Uphill walking requires more ankle plantarflexion and dorsiflexion than level
      walking. A limitation of the ankle joint mobility especially in dorsiflexion could therefore
      lead to additional or greater changes in gait patterns (hindfoot and forefoot kinematics)
      during uphill walking.

      The primary objective is:

      • To compare differences in hindfoot and forefoot kinematics between level and uphill
      treadmill walking in relation to passive range of motion

      The secondary objectives are:

        -  To compare lower leg muscle activation during level and uphill treadmill walking between
           patients after LLC and healthy subjects

        -  To test the association between muscle strength, muscle activation patterns and hindfoot
           and forefoot kinematics during level and uphill walking and heel rise

        -  To relate clinical outcome of LLC surgery by functional scores to passive range of
           motion
    

Detailed description: 
      At the initial assessment, written informed consent will be obtained before participants will
      undergo a clinical exam (inspection and palpation of the foot, measurement of bilateral
      passive ankle range of motion). All participants will complete the Short Form (SF)36 and the
      Foot Function Index20 to obtain pain and functional scores (approximate duration: 30
      minutes). Participants will be able to familiarize with treadmill walking at their preferred
      walking speed. Surface electrodes will be placed bilaterally over the tibialis anterior,
      gastrocnemius medialis and lateralis, soleus, and peroneus brevis. Isokinetic muscle strength
      in ankle plantarflexion/ dorsiflexion and inversion/eversion will be tested using the Biodex
      system 4 Pro (approximate duration: 45 minutes). Reflective surface markers will be placed
      bilaterally on anatomic landmarks according to the Plug In Gait model and a specific foot
      model. These markers are seen by 6 Vicon MX cameras. Participants will be asked to stand on
      the treadmill (h/p cosmos, Zebris), and data for a standing reference trial will be
      collected. Single-limb heel rise performance with each leg will be tested on the treadmill
      while kinematic, electromyography (EMG), and pressure data will be measured. Participants
      will then walk barefoot for 2 minutes at 0% slope while kinematic, EMG, and pressure data
      will be recorded. Subsequently, the treadmill incline will be increased to 15%, and data for
      2 minutes walking at this slope will be recorded followed by three heel rises (approximate
      duration: 45 minutes). The estimated total time for each participant is 120 minutes.
    

Intervention name(s): Lateral column lengthening osteotomy
Intervention type(s): Procedure
Intervention description(s): Lengthening osteotomy of the lateral column of the foot
Observational model: Cohort
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        20 patients who had undergone lengthening osteotomy of the lateral column of the foot 2 to
        10 years prior and 20 age and sex matched healthy subjects
      
Keywords: gait analysis; electromyography; strength test; walking