Hard-soled Shoe Versus Short Leg Walking Cast for a Fifth Metatarsal Avulsion Fracture: A Randomized Multicenter Noninferiority Trial

NCT ID: NCT02050698

Last Updated: 2015-10-14

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: NA
• Total Enrollment: 96 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2014-01-31
• Study Completion Date: 2017-01-31

Brief Summary

Fifth metatarsal avulsion fractures are common and can usually be treated conservatively. Symptomatic care consisting of protected weightbearing in a hard-soled shoe, air-cast walking boot, or below-knee walking cast have been successful. Several papers reported that early rehabilitation may decrease ankle stiffness, muscle and bone atrophy, and aids in early return to activities. However, early motion of the ankle joint may have the risk of displacement of the fifth metatarsal avulsion fractures. However, studies using hard-sole shoe for protected weightbearing and allowing motion of the ankle joint had successful results. Clapper et al. compared the results of hard-soled shoe and walking cast for a fifth metatarsal avulsion fracture and reported that all avulsion fractures healed uneventfully and that the results were similar between the two. However, this was not a randomized controlled trial.

Devices such as air-cast walking boot, plaster slipper, or Jone's dressing can also be used for the treatment. However, we decided to compare results of hard-soled shoe and short leg walking cast for the treatment of a fifth metatarsal avulsion fracture.

We hypothesized that the 100mm visual analogue scale (VAS) assessed on 6 months after a fifth metatarsal avulsion fracture treated with protected weightbearing in a hard-soled shoe is not inferior to protected weightbearing in a short leg walking cast but is superior to short leg walking cast with respect to time to return to normal daily life and patient's satisfaction.

Detailed Description

This study is a noninferiority, randomized controlled trial of patients presenting to multiple centers. The primary outcome measure is the 100mm VAS assessed on 6 months after a fifth metatarsal avulsion fracture. 100mm VAS was compared between the experimental group (hard-soled shoe) and the control group (short leg walking cast) on 6 months follow-up examination. The 100mm VAS is widely used self assessment tool for evaluating pain after fracture. The secondary objectives were to determine whether hard-soled shoe was superior to short leg walking cast with respect to time until return to normal daily life and patient's satisfaction.

The sample size was determined using methods appropriate for noninferiority trials, assuming 90% power and a significance level of 0.05. We performed a pilot study on 18 patients and assessed 100mm VAS on 6 months. Pooled standard deviation was 16.6. To find out whether the hard-soled shoe is not inferior to short leg walking cast for a fifth metatarsal avulsion fracture, 74 patients were required to have 90% power that the lower limit of an one-sided 95% confidence interval for the difference between two treatments will be above the noninferiority margin of -10. We assumed the drop-out rate to be 20%. Adding this number, 96 patients were required for the study.

Determination of the noninferiority margin was based on clinical significance. Todd et al. reported on a study of 48 patients that the minimum clinically significant difference of 100mm VAS was 13mm and that differences of less than this amount, even if statistically significant, are unlikely to be of clinical significance. We decided that the noninferiority margin at 10 mm difference which is less than this amount will be adequate to prove noninferiority of the experiment group (hard-soled shoe) over the control group (short leg walking cast).

After 1 weeks of immobilization in a short leg posterior splint, patients are randomized to experiment group (hard-soled shoe) and control group (short leg walking cast). Randomization was stratified by the study centers. Block randomization were used and the investigators were blinded to the block sizes being used to ensure allocation concealment. Delayed union was defined as a lack of bridging callus on 3 of 5 cortices at 12 weeks. Nonunion was defined as lack of cortical bridging or a clearly visible fracture line, at 14 weeks post injury.

If a subject had discontinued prior to completion of 6 months, the last observation was carried forward for the intent-to-treat analysis. Subjects who crossed over to the other treatment arm, for an example, patients in experiment group(hard-soled shoe) who changed to short leg walking cast or in control group (short leg walking cast) who changed to hard-soled shoe, were analyzed according to their initial group allocation for the intent-to-treat analysis. Additionally, an as-treated (per-protocal) analysis was also conducted on patients who completed the 6 months follow-up with the protocol assigned.

Although previous studied have not documented an increase risk of reduction loss with protected weightbearing in a hard-soled shoe protocol, a safety rule was put in place to assure patients, clinicians, and the health research ethics board that the safety of our patients was a priority. Reduction loss was not a primary outcome, but it was monitored carefully regardless of published evidence. A safety rule established a priori eliminated any dissent among the research team and participating surgeons about stopping the study in the event of an apparent adverse outcome related to protected weightbearing in a hard-soled shoe. If a difference of greater than three spontaneous reduction loss occurred between the groups, the intervention would be halted. A reduction loss or metal failure was defined as one that occurred without patient instigation of inappropriate activity. The reduction loss was to be monitored by study personnel not involved in the outcome assessment.

Conditions

Metatarsal Fracture; Treatment

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

short leg walking cast

After 1 weeks of immobilization in a short leg posterior splint, patient is allowed protected weightbearing in a short leg walking cast

Group Type: ACTIVE_COMPARATOR

Protected weightbearing in a short leg walking cast

Intervention Type: PROCEDURE

Patients allocated to control group are allowed tolerable weightbearing in a short leg walking cast after one week of immobilization in a posterior splint

hard-soled shoe

After 1 weeks of immobilization in a short leg posterior splint, patient is allowed tolerable weightbearing in a hard-soled shoe

Group Type: EXPERIMENTAL

Protected weightbearing in a hard-soled shoe

Intervention Type: PROCEDURE

Patients allocated to experiment group are allowed tolerable weightbearing in a hard-soled shoe after one week of immobilization in a posterior splint

Interventions

Protected weightbearing in a hard-soled shoe

Patients allocated to experiment group are allowed tolerable weightbearing in a hard-soled shoe after one week of immobilization in a posterior splint

Intervention Type: PROCEDURE

Protected weightbearing in a short leg walking cast

Patients allocated to control group are allowed tolerable weightbearing in a short leg walking cast after one week of immobilization in a posterior splint

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

• age between 18 and 65 years
• fifth metatarsal avulsion fracture

Exclusion Criteria

• open fractures
• pathologic fractures
• a fifth metatarsal avulsion fracture combined with other lower extremity injuries such as Lisfranc injury
• patients with diabetes or neuroarthropathy
• patients with obesity (BMI >30, weight >100 kg)
• any other conditions that are expected to prevent the patients from following the study protocol

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Hallym University Kangnam Sacred Heart Hospital

OTHER

Sponsor Role: lead

Responsible Party

Hyong Nyun Kim

Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Hyong Nyun Kim, MD, PhD

Role: STUDY_CHAIR

Kangnam Sacred Heart Hospital, Hallym University College of Medicine

Hyong Nyun Kim, MD, PhD

Role: STUDY_DIRECTOR

Kangnam Sacred Heart Hospital, Hallym University College of Medicine

Locations

Sanbon Hospital, Wonkwang University College of Medicine

Gunpo, Gyeongi, South Korea

Site Status: RECRUITING

CHA Bundang Medical Center, CHA University

Seongnam, Gyeongi, South Korea

Site Status: RECRUITING

Kangnam Sacred Heart Hospital, Hallym University College of Medicine

Seoul, , South Korea

Site Status: RECRUITING

Countries

South Korea

Central Contacts

Hyong Nyun Kim, MD, PhD

Role: CONTACT

hyongnyun@naver.com

+82-2-829-5165

Facility Contacts

Yu Mi Kim, MD, PhD

Role: primary

castkim@hanmail.net

+82-31-390-2224

Young Rak Choi, MD

Role: primary

jeanguy@hanmail.net

+82-31-780-5298

Hyong Nyun Kim, MD, PhD

Role: primary

hyongnyun@naver.com

+82-2-829-5165

References

Todd KH, Funk KG, Funk JP, Bonacci R. Clinical significance of reported changes in pain severity. Ann Emerg Med. 1996 Apr;27(4):485-9. doi: 10.1016/s0196-0644(96)70238-x.

Reference Type: BACKGROUND

PMID: 8604867 (View on PubMed)

Clapper MF, O'Brien TJ, Lyons PM. Fractures of the fifth metatarsal. Analysis of a fracture registry. Clin Orthop Relat Res. 1995 Jun;(315):238-41.

Reference Type: BACKGROUND

PMID: 7634674 (View on PubMed)

Gray AC, Rooney BP, Ingram R. A prospective comparison of two treatment options for tuberosity fractures of the proximal fifth metatarsal. Foot (Edinb). 2008 Sep;18(3):156-8. doi: 10.1016/j.foot.2008.02.002. Epub 2008 May 19.

Reference Type: BACKGROUND

PMID: 20307430 (View on PubMed)

Heineck J, Wolz M, Haupt C, Rammelt S, Schneiders W. Fifth metatarsal avulsion fracture: a rational basis for postoperative treatment. Arch Orthop Trauma Surg. 2009 Aug;129(8):1089-92. doi: 10.1007/s00402-008-0756-x. Epub 2008 Sep 26.

Reference Type: BACKGROUND

PMID: 18818936 (View on PubMed)

Shahid MK, Punwar S, Boulind C, Bannister G. Aircast walking boot and below-knee walking cast for avulsion fractures of the base of the fifth metatarsal: a comparative cohort study. Foot Ankle Int. 2013 Jan;34(1):75-9. doi: 10.1177/1071100712460197.

Reference Type: BACKGROUND

PMID: 23386764 (View on PubMed)

Vorlat P, Achtergael W, Haentjens P. Predictors of outcome of non-displaced fractures of the base of the fifth metatarsal. Int Orthop. 2007 Feb;31(1):5-10. doi: 10.1007/s00264-006-0116-9. Epub 2006 May 23.

Reference Type: BACKGROUND

PMID: 16721621 (View on PubMed)

Wiener BD, Linder JF, Giattini JF. Treatment of fractures of the fifth metatarsal: a prospective study. Foot Ankle Int. 1997 May;18(5):267-9. doi: 10.1177/107110079701800504.

Reference Type: BACKGROUND

PMID: 9167925 (View on PubMed)

Other Identifiers

IRB2014-OS01

Identifier Type: -

Identifier Source: org_study_id