KCE-191232: A prospective, multi-center, randomized, parallel-group controlled PILOT trial to compare conservative versus surgical treatment of foot drop in peroneal nerve entrapment – Foot Drop

Summary (French or Dutch)

Patients with foot drop suffer from gait impairment and have an increased risk of falling. This can have severe consequences on a person’s mobility.
The goal of the study is to compare a conservative versus a surgical approach in the treatment of foot drop due to peroneal nerve entrapment. No previous study has directly compared these treatment strategies. Therefore we do not know if surgical release of the nerve is better than physiotherapy. 
If foot drop does not recover within 6 to 14 weeks, patients will be randomly allocated to conservative treatment or surgical decompression. The conservative treatment focuses on physiotherapy and gait rehabilitation. Surgical treatment consists of local decompression of the nerve through a small incision at the level of the knee.
Gait impairment, which represents the most important consequence of foot drop, will be assessed. Gait will be evaluated through the distance covered during the six-minute walk test. The difference in distance at randomization and 9 months will be compared and represents the primary endpoint of the study. This primary endpoint will be used to assess if foot drop recovers better after surgical decompression than conservative treatment. After 9 months patients in the conservative group can still undergo surgery.

Since studies comparing surgery versus no surgery or delayed surgery are challenging, a feasibility pilot study will be conducted in 5 centres in Belgium and 1 centre in the Netherlands. The go / no-go criterion to embark on a full scale study is the recruitment of at least 14 patients in these 6 centres after 6 months.

Trial Description

A prospective, multi-center, randomized, parallel-group controlled PILOT trial to compare conservative versus surgical treatment of foot drop in peroneal nerve entrapment – Foot Drop

Participants (P)

Patients with electrodiagnostic (EDX)-documented peroneal nerve entrapment with persisting foot drop 10 +/- 4 weeks after onset of symptoms will be included in the trial. Imaging to exclude a compressive mass at the level of the fibular head is required, since these patients are excluded from the trial.

Intervention (I)

Decompressive release of the peroneal nerve at the level of the fibular head

Control (C)

Maximal (prolonged) conservative treatment with physiotherapy aiming at muscle strengthening and gait rehabilitation.
Allowed: use of foot-ankle orthosis / electrostimulation and other therapies reflecting daily practice

Outcome (O)

Difference in distance (in meters) covered during the six-minute walk test between baseline and 9 months after randomization

Trial Design

This is a prospective, multi-center, randomized, parallel-design study.
This is a superiority trial: the goal is to prove superiority of surgery to maximal conservative treatment.
Subjects will be randomized 1:1 to surgery or to conservative treatment. No cross-over is allowed until the primary endpoint is assessed at 9 months after randomization. After the primary endpoint is assessed, cross-over to surgery is allowed, with extended follow-up at 18 months after randomization (equals 9 months after primary endpoint).

Sample Size

Overall, the study will enrol 182 subjects in 2 treatment arms, 91 subjects per arm.
The statistical analysis plan will contain a blinded sample size reassessment to verify if the planned sample size is sufficient to show the minimal clinical important difference.

Trial duration

Pilot 6 months

Full study 48 months


€327 000 (Pilot)


Open to recruitment


Trial team


UZ Leuven

Chief Investigator

Prof. Dr. Tom Theys

Participating sites and Investigators

6 (pilot)
29 with 2 in NL (full study) (with reservation)

External partner



13/12/2021 (Pilot)

Q4 2024 (Full study)





Patient documents

in French

in Dutch


Clinicaltrials.gov: NCT04695834


Funding scheme

2019 Investigator led