Comparison Different Method Treatment in Tuberosity Fractures of the Proximal Fifth Metatarsal

Overview

Fracture of the base of the fifth metatarsal is one of the most common injuries in ankle trauma. There are many conservative treatment protocols for fifth metatarsal base fractures which have up to 99% success. Short leg cast and walking boot are conservative treatment methods that aim to prevent weight-bearing. There are many different conservative treatment methods that allow weight-bearing such as an elastic bandage. There was no significant difference between cast and symptomatic treatment in the previous studies. Muscle atrophy developing after immobilization with cast may adversely affect the daily activities of the patient in the first few months. However, there was no study comparing the effect of these two treatment methods on ankle muscle strength. In this study, the investigators compared the strength of the ınjured and healthy ankle muscle when symptomatic and cast treatment methods are applied to patients with tuberosity fractures of proximal fifty metatars. In addition, patients' functional, clinic and radiological outcomes were also compared.

We prospectively treated 73 patients with 5th metatarsal base fractures (Zone 1) who came to the emergency department. Patients were allocated to a treatment group using an electronic random number generator. The generation of an even number randomized the participant to a below-knee cast, and an odd number to a double-layered elasticated bandage. In all, patients were allocated to wear a double layered elasticated bandage (group 1) applied by S.B and patients were given a below-knee cast (group 2) applied by D.K. Duration of both treatments were for four weeks and the cast removed in that time in our clinic. This reference form of treatment was the same as in previous reports. The non-injured extremity was measured with isokinetic test at initial injury time for evaluation of side effect of immobilization after treatment. At that time, patients were asked for height, weight and pain scores. Body muscle index was calculated for all patients. Tobacco using was also asked.To measure clinical outcomes, using the validated Visual Analogue Scale Foot and Ankle (VAS-FA) score \[7\] and The EuroQol-5D visual analogue scale (EQ-5D VAS) score were used \[8\]. The VAS-FA score ranges from 0 to 100 points: higher scores indicate a better functional outcome. EQ-5D VAS score was used as a secondary outcome measure: this ranges from 0 to 100. Baseline functional scores were collected at the time of consult in the clinic. Both ankle plantar-dorsiflexors and inversion-eversion'strength (peak torque %BW (Body Weight)) were measured with an isokinetic dynamometer (Cybex Humac Norm, CA, USA) at Isokinetic Test Laboratory of Sports Medicine in the Istanbul Medical Faculty. Test procedure was performed by the same investigator (T.Ş) in all cases for ensuring standardization. The muscle strength can be defined as the capacity of a muscle to withstand great force. Injured extremity values were compared with non-injured extremity. The non-injured extremity was measured at initial injury time for evaluation of side effect of both treatment methods. The tests were started with non-injured sides of the patients and measurements at low angular velocity. The dynamometer was calibrated at the beginning of each testing session. Subjects were tested in prone position and stabilized in the exercise chair as per the manufacturer's recommendation. The anatomical axis of the ankle was aligned with the axis of the dynamometer while the foot was secured to the foot plate with velcros. Proximal stabilization was achieved with the straps at the thigh and calf. In the test, dorsiflexion-plantarflexion and inversion-eversion peak torque force (strength) measurements were performed in 3 trials and 3 tests repetitions at 30 degrees/sec angular speed for both side of the patient. All of the patients were given follow-up appointments at 2, 4, 8, 12 and 24 week interval at our clinic. Radiographs were similarly scheduled for 4, 8, and 12 week intervals to assess bony healing. However, functional outcomes and isokinetic test was applied also at 24 week control. At second visit, isokinetic test was not applied. These studies were started on fixed ground and then continued on moving boards. Standard rehabilitation program was given for all patients each group included joint mobilizations, passive stretching, electrotherapy-ice compression for pain relieving and ankle proprioceptive exercises, as considered necessary by same author (T.Ş).