Simulation of Altered Excursion of the Pronator Quadratus

Abstract

The purpose of our study was to determine whether restricted excursion of the PQ muscle alone could affect forearm rotation. Materials and Methods Specimen PreparationEight adult, fresh-frozen, unmatched upper extremities were amputated at the mid-humerus. All of the specimens used appeared free from any prior trauma. The skin, subcutaneous tissue, and forearm flexor and extensor muscles were excised to the level of the wrist joint. The biceps tendon, elbow Keywords► pronator quadratus ► distal radius fractures ► volar approach to ORIF of distal radius ► fracture ► complications of distal radius fracture ► forearm rotation AbstractBackground Loss of forearm rotation is frequently seen after healing of distal radius fractures. Questions/Purposes Our purpose was to determine whether restricted excursion of the pronator quadratus muscle can affect forearm rotation. Methods We evaluated the relationship between pronator quadratus excursion and forearm rotation in a cadaveric model. Eight adult fresh-frozen above-elbow specimens were attached to a mounting device that permitted free rotation of the forearm around its ulnar axis. Forearm rotation was measured with a protractor while alternating pronation and supination loads were applied. Measurements were repeated after restricting the excursion of pronator quadratus by 10, 20, and 30% of its initial length. Results There was a mean 15°loss of supination for each 10% reduction in pronator excursion. There was no significant effect on pronation. Conclusions We conclude that, independent of any bone deformity or nearby joint stiffness, posttraumatic scarring of this muscle may result in a loss of supination.

Evaluation of sparing the pronator quadratus for volar plating of distal radius fractures: a retrospective clinical study

“…Some surgeons, including Goorens CK, believe that repairing the PQ muscle only relieves the patient's postoperative pain at an early stage [ 14 , 15 ]. In addition, some surgeons consider that whether or not the PQ muscle is repaired intraoperatively is not significantly related to the patient's postoperative functional recovery of the wrist [ 16 , 17 ]. Fenglei Shi concluded in a study that whether or not to repair the PQ muscle may not improve late wrist function in patients [ 18 ].…”

Biomechanical Causes of Fracture Non-union after Diaphyseal Forearm Fracture Fixation: an in Silico Analysis. Case Study

“…The most important factors contributing to fracture non-union are be lieved to include extensive tissue laceration, deep tissue contamination at the fracture site with cutaneous or en vironmental flora, impaired blood supply, meta bolic diseases, particularly abnormal calcium metabolism, impaired immune responses, infectious and neoplastic diseases, chemotherapy, prolonged antibiotic therapy, steroid therapy, and damage to mesenchy mal lineage precursor stem cell [6,8,9,10,11,12,13,14,15]. Another important factor contributing to non-union in forearm bone shaft fractures is fixation instability and disturbed "biomechanical silence" within the forearm bone shafts resulting from the action of pronators from the anterior forearm muscle group, mainly the pronator teres, pronator quadratus and flexor carpi radialis, the radial part of the flexor ramienia, głównie mięśnia nawrotnego obłego i nawro tnego czworobocznego oraz mięśni zginacza promieniowego nadgarstka, promieniowej części zginacza powierzchownego palców i promieniowej części zginacza głębokiego palców [16,17,18,19,20,21,22]. Z omawianych czynników sprzyjających zaburzeniu zrostu w tym przypadku, mieliśmy do czynienia poza przebytą sterydoterapią, z obciążeniem przewlekłym nikotynizmem, zaburzeniami gospodarki wapniowej oraz kinezyterapią w zakresie przekraczającym wytrzymałość zespolenia, przy istniejących już pierwotnie, tj.…”

“…U pacjenta stwierdzano więc m.in. przewagę wymiarów szerokościowych nad podłuż-nymi, szeroką klatkę piersiową, grube kończyny, a także dłonie i stopy, szeroką miednicę, jak również digitorum superficialis, and the radial part of the flexor digitorum profundus [16,17,18,19,20,21,22]. In our case, the factors contributing to fracture nonunion included a history of steroid therapy, chronic tobacco use, abnormal calcium metabolism, and kinesiotherapy exceeding the resistance of the fixation in a patient with pre-existing, i.e.…”

Evaluation of sparing the pronator quadratus for volar plating of distal radius fractures: a retrospective clinical study

“…Some surgeons believe that repairing the PQ muscle only relieves the patient's postoperative pain at an early stage [14]. In addition, some surgeons consider that whether or not the PQ muscle is repaired intraoperatively is not signi cantly related to the patient's postoperative functional recovery of the wrist [15,16].…”