Metacarpal Neck Fractures: Results of Treatment with Traction Reduction and Cast Immobilization (2025)

Abstract

Although fractures of the fifth metacarpal neck (boxer’s fractures) are common, their treatment can be problematic. A description of a technique utilizing traction reduction is presented in this paper. The records and radiographs of 59 patients who underwent reduction using longitudinal traction and subsequent immobilization in a specially molded cast were retrospectively reviewed. On average, 80% of initial fracture angulation in the sagittal plane was corrected, and only 1° of this correction was lost at the discontinuation of casting (3–4weeks). We have found this technique to be highly effective in the treatment of boxer’s fractures. Advantages of this treatment include its efficacy, ease, and improved patient tolerance over other casting techniques.

Introduction

Metacarpal neck fractures are among the most common of hand fractures with those involving the fifth metacarpal (boxer’s fractures) being the most common [2]. These fractures result from a longitudinal compression force acting on a flexed metacarpophalangeal joint (MCP)—usually when a clenched fist strikes a solid object. The resultant fracture is usually unstable with volar angulation due to comminution of the volar cortex and the deforming action of the interossei.

Many methods of immobilization have been described to maintain reduction of metacarpal neck fractures. Early methods included immobilization over a roller bandage and banjo splinting [5, 9]. In the 1920s and 1930s, several authors espoused management with straight dorsal splinting, immobilizing the MCP joints in extension [5, 6]. Contemporary treatment usually relies upon reduction by the Jahss maneuver followed by cast or splint immobilization. Recent methods of immobilization have included: anterior splinting, anterior–posterior splinting, ulnar splinting, fracture braces, and immobilization with adhesive tape [1, 3, 4, 7, 8]. All typically immobilize the reduced fracture with the MCP joints in flexion. Although reduction of these fractures is usually successful using the Jahss technique, successful maintenance of the reduction has remained a vexing problem.

Over the past decade, the senior author has developed and employed a different technique for reduction and immobilization of fifth metacarpal neck fractures which we have found to be highly successful. The technique is based upon reduction by longitudinal traction only and subsequent immobilization using a three-point molded plaster cast with the interphalangeal (IP) joints free. Advantages of this treatment method include its efficacy, ease of application, freedom of IP joint motion, and improved patient tolerance. Anesthesia is not necessary with this technique. We report in this paper a description of this technique and the results of patients treated by this method by the senior author as well as other attending staff at our institution.

Materials and Methods

The records of all available patients diagnosed at our institution with a boxer’s fracture or a fracture of the fifth metacarpal neck from 1988 to 2006 were retrospectively reviewed to determine which underwent fracture management using the techniques outlined below. The corresponding injury and immobilization radiographs were then reviewed to ensure accuracy of diagnosis and to confirm casting in accordance with this technique. Fifty-nine patients had been treated with the described technique and had sufficient radiographic follow-up (at least 3months) for review and measurement. Additional information abstracted from the patient records included age, gender, hand dominance, and mechanism of injury.

Initial injury, postreduction, and final follow-up radiographs were reviewed. Anterior–posterior and true lateral views of the metacarpal were available for all patients. Oblique views of the hand were not consistently obtained. Fracture angulation was measured on the true lateral view using a fine goniometer centered at the fracture site on the dorsal cortex. Three sagittal angulation measurements were made: initial injury, postreduction (in cast), and final follow-up. Accepting the normal metacarpal neck–shaft angle to be 15°, the degree of correction and subsequent maintenance/loss of correction was determined [3].

On initial presentation, various modes of nonoperative treatment were employed. Regardless of initial treatment modality, all study patients subsequently underwent fracture reduction using longitudinal traction in finger traps with subsequent cast immobilization within the first week postinjury. Our technique of traction reduction and casting of boxers’ fractures is described below.

Results

Most of the patients in this investigation were young males who sustained their boxers’ fracture by striking an object with a clenched fist. Of the 59 patients, 53 were male (90%). Patient age averaged 28years (range, 12 to 86years). Five patients were less than 18years of age. With respect to hand dominance, 51 of the 59 patients had injured their dominant hand (86%).

Of the 59 patients, 44 sustained their fracture by striking an object with a clenched fist. A fall directly onto the hand produced the boxers’ fracture in another eight patients. For the remaining patients, four patients were injured in a motor vehicle accident, two were involved in industrial accidents, and one sustained his injury when his hand was caught in a metal gate.

All fractures were reduced and immobilized using the aforementioned techniques within 7days of injury. Initial fracture angulation measured on the lateral radiographs averaged 32° (range, 13–54°) in excess of the normal head–shaft angle. Following traction reduction, fracture angulation averaged 6° (range, 0–20°), designating an average 81% correction of the initial angulation. At final follow-up, fracture angulation averaged 6.9° (range, 0–20°), indicating an average loss of less than 1° from the initial correction. In all 59 patients, the difference between the initial postreduction angulation and that at final follow-up was 4° or less. The average MCP arc of motion at most recent follow-up was 88° (range, 76–105°).

Discussion

Numerous treatment measures have been described for the treatment of boxer’s fractures, yet their management remains a controversial problem. While the indications for the reduction and immobilization of these fractures are less than clear, we believe that acceptance of significant angulation of fifth metacarpal neck fractures does not uniformly lead to fully functional results.

We have found that the use of longitudinal traction (finger traps) for fracture reduction corrects an average of nearly 80% of initial fracture angulation in the sagittal plane. For most patients, the result is near-anatomic. For no patient was a correction of less than 50% achieved. We have also found that the maintenance of this reduction is reliably achieved using the three-point molded plaster cast we describe in this paper. For all patients in this study, the final angulation measurement differed by 4° or less from the initial correction measurement.

In addition to producing consistent results, this method affords further advantages in that no special materials are required and that anesthesia is generally not needed. Also, this method may be performed on an elective basis up to 1week following injury. The special cast allows nearly full motion of the MCP and IP joints of the thumb, index, and long finger as well as IP motion of the ring and small fingers. This regimen has been highly successful in maintaining digital mobility while effectively holding fracture reduction. Furthermore, we have found that this technique obviates the need to consider open or closed reduction with internal fixation in the majority of patients.

References