Single Event Multilevel Surgery (SEMLS)

Original Editor - Lauren Heydenrych

Top Contributors - Lauren Heydenrych  

Introduction[edit | edit source]

Single-event multilevel surgery (SEMLS) is a single complex surgical procedure whereby "...correction of all musculoskeletal deformities producing gait abnormalities..." (pg. 1) are addressed. This has replaced older, single-level surgery. A combination of muscle-tendon lengthening, tendon transfers, rotational osteotomies, and joint stabilizations are performed within the procedure. Thus addressing multiple anatomical levels from which gait abnormalities stem. The procedure itself is based on a detailed biomechanical assessment. [1][2]

Aim of SEMLS[edit | edit source]

The aim of a SEMLS procedure is to produce functional changes in body structures and function which will create positive changes to the levels of activity, in particular gait, ultimately improving participation.[1]In addition, the ability to perform multiple procedures in a single surgery aims to decrease the rehabilitation period to a single period.[3]

In most studies home, school and community ambulation are assessed. Here parameters such as structural gait analysis, ambulation with or without assistive devices, and long term quality of life are assessed. [1][4]

History and Development of SEMLS[edit | edit source]

SEMLS was first described in 1985 by Norlin and Tkaczuk as well as Browne and McManus in 1987.[4]

Initially, follow-up research done by Norlin and Tkaczuk (1992) reported improved gait patterns using video gait analysis. Further studies, performed more recently (between 2013 and 2020), have also found favorable outcomes. These however, have been limited to between 1 and two years post operative follow-up.[4]

In a systematic review performed by McGinley et al. (2011) covering research papers on SEMLS (or similarly described surgical interventions) it was found that the level of research was of poor quality up until 1999. [5]It was in 1999 that Thomas et al.[6] produced a study that included outcome measures of both the GMFCS and gait parameters. In the years following, other studies stood out which included outcomes linking to the ICF model.[5]

Advantages[edit | edit source]

The advantages in combining multiple procedures into one mean that hospital stay and rehabilitation time is decreased. There is also the possible decrease in complications. [4]

Increase in passive range of movement (PROM), selected gait parameters and overall gait index as well as energy efficiency have been generally reported.[5]

Disadvantages[edit | edit source]

Complications have generally not been reported to date. Which highlights the need for studies which include this.[5]

To date, no large scale improvement in the GMFCS scores have been noted. This does not necessarily mean there are none, but this aspect has not been reported on.

Considerations[edit | edit source]

  • There is always the possibility of relapses and new biomechanical problems necessitating further surgical intervention.[4]
  • The success of the procedure requires intensive post-operative rehabilitation. [1]
  • Post operative level of function initially decreases, observed with follow-up 3 and 12 months. Subsequent stabilization of function and then improvement is generally noted 2 years post-operatively[1][2]
  • The older the child, the better the long term benefits appeared to be. These benefits were based on gait kinematics.[3]

Candidates[edit | edit source]

SEMLS is usually performed on children diagnosed with Cerebral Palsy, with a Gross Motor Function Classification System (GMFCS) of I, II or III. The procedure itself is most commonly performed on candidates with GMFCS level III.[1]

Physiotherapy post SEMLS[edit | edit source]

Details of rehabilitation are generally poorly reported. In addition, procedures and subsequent rehabilitation protocols tend to vary widely.[5]

The general aim of postoperative rehabilitation tends to focus on:

  • Range of motion (ROM)
  • Balance
  • Strength
  • Function (unspecified in literature)

It must be noted that in a systematic review of SEMLS intervention, the predominating aspect in postoperative rehabilitation is dealing with pain in the weeks following surgery.[5]

Initiation and duration of therapy[edit | edit source]

Again, the initiation of therapy and duration vary. In a retrospective study performed in 2011, mobilisation of patients began 7-10 days after surgery and continued as intensive rehabilitation for some weeks after.[3] In another study performed on a cohort group, an intensive rehabilitative program was initiated 6 weeks after therapy and continued for 12 weeks, or 4 to 6 if treated as in-patients. [1]

Resources[edit | edit source]

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Harvey A, Rosenbaum P, Hanna S, Yousefi-Nooraie R, Graham KH. Longitudinal changes in mobility following single-event multilevel surgery in ambulatory children with cerebral palsy. Journal of Rehabilitation Medicine. 2012 Feb 1;44(2):137-43.
  2. 2.0 2.1 Edwards TA, Prescott RJ, Stebbins J, Wright J, Theologis T. What is the functional mobility and quality of life in patients with cerebral palsy following single-event multilevel surgery?. Journal of children's orthopaedics. 2020 Apr;14(2):139-44.
  3. 3.0 3.1 3.2 ŠVEHLÍK M, Steinwender G, Kraus T, Saraph V, Lehmann T, Linhart WE, Zwick EB. The influence of age at single‐event multilevel surgery on outcome in children with cerebral palsy who walk with flexed knee gait. Developmental Medicine & Child Neurology. 2011 Aug;53(8):730-5.
  4. 4.0 4.1 4.2 4.3 4.4 Rutz E, Baker R, Tirosh O, Brunner R. Are results after single-event multilevel surgery in cerebral palsy durable?. Clinical Orthopaedics and Related Research®. 2013 Mar;471:1028-38.
  5. 5.0 5.1 5.2 5.3 5.4 5.5 McGinley JL, Dobson F, Ganeshalingam R, Shore BJ, Rutz E, Graham HK. Single‐event multilevel surgery for children with cerebral palsy: a systematic review. Developmental Medicine & Child Neurology. 2012 Feb;54(2):117-28.
  6. Thomas SS, Buckon CE, Piatt JH, Aiona MD, Sussman MD. A 2-year follow-up of outcomes following orthopedic surgery or selective dorsal rhizotomy in children with spastic diplegia. Journal of Pediatric Orthopaedics B. 2004 Nov 1;13(6):358-66.
  7. Trishla Foundation. Cerebral Palsy Affected Children with Crouch Gait : Outcome After SEMLS. Available from: [last accessed 01/03/2023]
  8. Anne-Laure Guinet. Rehabilitation after SEMLS in children with cerebral palsy - WFNR&SOFMER Congress 2020. Available from: [last accessed 01/03/2023]