J Korean Fract Soc.  2017 Apr;30(2):69-74. 10.12671/jkfs.2017.30.2.69.

Ultrasonographic Assessment of the Pronator Quadratus Muscle after Surgical Treatment for Distal Radius Fractures

• Choi DH
• Chung HK
• Lee JW
• Kim CH
• Choi YS

• KMID: 2376612
• DOI: http://doi.org/10.12671/jkfs.2017.30.2.69

Abstract

PURPOSE
This study was to assess the morphological changes of the pronator quadratus (PQ) muscle using an ultrasonography in the volar locking plate fixation group and in the percutaneous K-wire fixation group for distal radius fracture, and to evaluate the impact on clinical outcomes.
MATERIALS AND METHODS
Fifty-four patients who received surgical treatment for distal radius fracture were enrolled in this study. They were divided into two groups according to treatment modality: Group 1 included 34 patients who underwent internal fixation with volar locking plate and Group 2 included 20 patients with percutaneous K-wire fixation. Thickness of the PQ muscle was measured using an ultrasonography at the final follow-up. We evaluated the outcomes using the Mayo wrist score, wrist range of motion, and grip strength at the final follow-up.
RESULTS
Compared with the uninjured side, thickness of the PQ muscle showed 31.9% of mean atrophy in Group 1 and 11.4% in Group 2. The atrophy of PQ muscle was severe in Group 1 (p=0.01). However, there was no significant difference in the mean Mayo wrist score between the two groups (83.1±10.9 in Group 1 and 80.2±8.9 in Group 2, p=0.28), except a mild limitation of pronation in Group 1.
CONCLUSION
The healed PQ muscle from fracture itself after distal radius fracture revealed a morphological atrophy. Moreover, the volar locking plate resulted in greater atrophy of the PQ muscle, but there was no specific impact on clinical outcomes.

Keyword

Distal radius fracture; Pronator quadratus; Ultrasonography

MeSH Terms

Atrophy
Follow-Up Studies
Hand Strength
Humans
Pronation
Radius Fractures*
Radius*
Range of Motion, Articular
Ultrasonography
Wrist

Figure

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  Fig. 1 Ultrasound examination in longitudinal view shows a significant decrease (40%) in the thickness of pronator quadratus muscle (arrows) at postoperative 21 months of volar locking plate.

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