Surgery description
MHL is mainly considered for children with flexed-knee gait (i.e., an increased knee flexion during gait) and is the most common gait abnormality in children with CP. FDO on the other hand is used in children with excessive internal hip rotation and femoral anteversion. Both gait abnormalities can result in progressive gait deterioration or an inability to walk. Most surgeons use a combination of history taking, physical examination, radiographic findings, gait analysis, and past experience to decide which patient is a good candidate for surgery.
Methodology
Fifteen experienced orthopaedic surgeons created a list with commonly performed surgical procedures and decided to focus initially on FDO and MHL. They then rated the level of evidence individually in five categories:
- clinical problem/ history;
- symptoms;
- physical exam;
- 3-D gait analysis;
- intraoperative exam.
Consensus for MHL
Most surgeons relied on 3-D gait analysis data as indicators of shortened hamstrings; excessive knee flexion at initial contact or terminal swing and decreased pelvic tilt. They agreed that knee flexion contractures of more than 10 degrees should be surgically addressed during surgery or beforehand. They also concluded that the popliteal angle should not be vigorously tested under anaesthesia to avoid stretch injuries to the sciatic nerve.
Consensus for FDO
The surgeons agreed that excessive hip internal rotation during 3-D gait analysis was an important contributor, specifically if it was increased by 15 degrees. On physical examination, 30 degrees of increased femoral anteversion and 60 degrees of increased hip internal rotation were established as indicators for FDO. However, they raised that the physical exam should be carefully considered due to repeatability problems. Many experts also recommended to incorporate a mild overcorrection in younger children with CP.
> From: McCarthy et al., J Child Orthop 14 (2020) 50–57 . All rights reserved to The Author(s). Click here for the online summary.
Want to read deeper into this topic? A free version of the full text article is available online for free. You can find it here!
Expert opinion
It is almost impossible to evaluate surgical outcomes after SEMLS in ambulatory children with CP, due to the heterogeneity of the group and the heterogeneity of SEMLS. This makes it difficult to decide which surgical procedures should be used and results in a great variability between surgical recommendations.
This article is therefore a great start to address this problem and find consensus. However, I feel the consensus remains vague and could be more precise. More articles with a similar approach would be very helpful.
