European Spine Journal (2018) 27:1365–1374
Comparable clinical and radiological outcomes between skipped‑level
and all‑level plating for open‑door laminoplasty
Jason Pui Yin Cheung
· Prudence Wing Hang Cheung
· Amy Yim Ling Cheung
· Darren Lui
Kenneth M. C. Cheung
Received: 10 September 2017 / Revised: 27 December 2017 / Accepted: 19 February 2018 / Published online: 28 February 2018
© Springer-Verlag GmbH Germany, part of Springer Nature 2018
Purpose To compare the clinical and radiological outcomes between skipped-level and all-level plating for cervical
Methods Patients with cervical spondylotic myelopathy (CSM) treated by open-door laminoplasty with minimum 2-year
postoperative follow-up were included. All patients had opening from C3–6 or C3–7 and were divided into skipped-level or
all-level plating groups. Japanese Orthopaedic Association (JOA) scores and canal measurements were obtained preopera-
tively, immediate (within 1 week) postoperatively, and at 2, 6 weeks, 3, 6 and 12 months postoperatively. Paired t test was
used for comparative analysis. Receiver operating characteristic analysis was used to determine the canal expansion cutoﬀ
for spring-back closure.
Results A total of 74 subjects were included with mean age of 66.1 ± 11.3 years at surgery. Of these, 32 underwent skipped-
level plating and 42 underwent all-level plating. No signiﬁcant diﬀerences were noted between the two groups at baseline
and follow-up. Spring-back closure was observed in up to 50% of the non-plated levels within 3 months postoperatively. The
cutoﬀ for developing spring-back closure was 7 mm canal expansion for C3–6. No diﬀerences were observed in JOA scores
and recovery rates between the two groups. None of the patients with spring-back required reoperation.
Conclusions There were no signiﬁcant diﬀerences between skipped-level and all-level plating in terms of JOA or recovery
rate, and canal diameter diﬀerences. This has tremendous impact on saving costs in CSM management as up to two plates
per patient undergoing a standard C3–6 laminoplasty may be omitted instead of four plates to every level to achieve similar
clinical and radiological outcomes.
Level of evidence III.
Graphical abstract These slides can be retrieved under Electronic Supplementary Material.
[Key words: cervical spondylotic myelopathy; plates; spring-back;
1.Skipped-level and all-level plating have equal clinical and
2.Spring-back closure was observed in 50% of non-plated levels but
did not affect the clinicaloutcome
3.At least 7mm canal expansion can reduce the risk of spring-back
[Cheung JP et al. Comparable clinicaland radiologicaloutcomes
between skipped-level and all-level plating for open-door
(a) Skipped-level plaƟng at C4 and C6 for C3-7 laminoplasty; (b)
Skipped-level plaƟng at C5 for C3-6 laminoplasty.
[Cheung JP et al. Comparable clinical and radiological outcomes
between skipped-level and all-levelplatingfor open-door
Take Home Messages
1. Skipped-levelplatingisnon-inferiorto all-levelplatingin termsof
clinicaland radiological outcomes for laminoplasty up to an average of
5 years follow-up
2. A threshold of at least 7mm canal expansion avoidsspring-back
3. Implant costscan be reduced by at least 50% if skipped-levelplating
[Cheung JP et al. Comparable clinicaland radiological outcomes
betweenskipped-leveland all-level platingfor open-door
Keywords Cervical spondylotic myelopathy · Plates · Spring-back · Skipped-level · Laminoplasty
Electronic supplementary material The online version of this
article (https ://doi.org/10.1007/s0058 6-018-5533-0) contains
supplementary material, which is available to authorized users.
Extended author information available on the last page of the article