Flexor Tenotomy and Ulcer Recurrence

Study Overview
=================
Brief Summary
-----------------
The main purpose of this study is to assess the efficacy of flexor tenotomy on the prevention of recurrence of toe ulcers in people with diabetes and a history of toe ulceration. Additionally, the investigators aim to assess interphalangeal joints (IPJ) and metatarsophalangeal joint (MTPJ) angles in a weight-bearing and non-weight-bearing position, bare-foot plantar pressure during walking and quality of life before and after the intervention and compare between study groups.

Detailed Description
-----------------
Foot ulcers are a frequent problem in patients with diabetes mellitus and can lead to amputations. Prevention of these ulcers is therefore of paramount importance. Claw/hammer toe deformity is commonly seen in patients with diabetes. These deformities increase the risk of ulcer development specifically at the (apex of) the toe. Tenotomy of the tendon of the flexor muscles of the toes (tendon tenotomy) can be used to treat the consequences of claw/hammer toe deformity with the goal to prevent ulcer recurrence. For indication and assessment of outcomes of flexor tenotomy, weight-bearing CT and dynamic barefoot plantar pressure measurement can be used. This mono-center investigator blinded randomized controlled trial will compare the flexor tenotomy with usual care (including orthoses and shoe offloading). The effect on ulcer recurrence, toe joint angles, barefoot plantar pressure and quality of life will be assessed and compared between the intervention and control group.

Official Title
-----------------
The Efficacy of Flexor Tenotomy on the Prevention of Recurrent Diabetic Foot Ulcers: a Randomized Controlled Trial

Conditions
-----------------
Hammer Toe Syndrome, Foot Ulcer, Diabetic

Intervention / Treatment
-----------------
* Procedure: Flexor tenotomy


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: A minimum age of 18 years Sufficient understanding of Dutch/English language Capable of filling out informed consent Peripheral polyneuropathy Diabetes mellitus type 1 or 2 A minimum of one claw/hammer toe A documented history of diabetic ulcers underneath the toe apex in the past 5 years Exclusion Criteria: No written informed consent Not meeting the inclusion criteria Open ulcers on the toes Previous participation in the study Pregnant women Concomitant participation in a study in which the patient is exposed to X-rays

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention<br>Flexor tenotomy | Procedure: Flexor tenotomy<br>* Minimally-invasive percutaneous needle flexor tenotomy of the long digital flexor tendon<br>|
| No Intervention: Controle<br>Usual-care | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ulcer recurrence | Ulcer recurrence on the toe, adjacent toe, and metatarsal heads | 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| DIPJ, PIPJ and MTPJ angles | DIPJ, PIPJ and MTPJ angles during weight-bearing and non-weight-bearing | Baseline, 6 and 12 months | 
| Barefoot pressure pattern | Barefoot pressure pattern | Baseline, 6 and 12 months | 
| Patient-reported outcome measures: EuroQol's EQ-5D-5L | Quality of life determined by EQ-5D-5L | Baseline, 6, 12 and 24 months | 
| Patient-reported outcome measures: SF-36 | Quality of life determined by SF-36 | Baseline, 6, 12 and 24 months | 
| Incremental cost-effectiveness in QALY's of flexor tenotomy after 2 years | Cost-effectiveness of additional flexor tenotomy compared to usual-care only | 24 months |