Pronation

The maximum isokinetic strength of the quadriceps was assessed using a dynamometer (MYORET RZ-450; Kawasaki Heavy Industries, Kobe, Japan). Prior to the muscle strength test, participants warmed up using a stationary cycling ergometer for 5 min at low resistance. The participant sat on the seat of the dynamometer and was stabilized using straps. The test was first performed with the dominant leg. Each participant performed two practice contractions, followed by five maximal effort contractions at 60°/s. The test was repeated on the non-dominant leg. The peak extension torque was recorded as raw data in Newton meters (Nm) and was normalized according to body weight (Nm/kg).
Handgrip strength was measured using a grip strength dynamometer (TKK 5401; Takei Scientific Instruments, Niigata, Japan). To perform the test, the participant was seated in a chair with the shoulders neutral, elbows at 90° flexion, and forearms neutral in supination/pronation. The participant was given verbal encouragement to squeeze the dynamometer as tightly as possible for 2 or 3 s. Two trials were performed for each measurement, and the higher value was used. The order of measurement between the right and left hands was randomized for each participant.^{10 (link))}

Ten patients undergoing posterior elbow surgery were selected for the present study. All patients were subjected to standard elbow radiographs (Fig. 2) as well as computed tomography (CT) scan (Fig. 3) with all procedures conducted in the orthopedic department of El-Demerdash hospital, Ain Shams University (prospective study). The study was approved by the University’s ethics committee (approval no. FMASU R 191/2022) and informed consent was signed by each patient.
Patients with displaced Mason type II isolated posteromedial radial head fracture with no neurovascular deficit were included in the study. On clinical examination, the patients had tenderness over the radial head and limitation of flexion-extension arc. The elbows were blocked in pronation with no active or passive supination. Exclusion criteria were: patients under the age of 18 years and revision surgery.

Patients were placed in the lateral decubitus position. A tourniquet was used in all cases. The elbow was exposed via a posterior incision, and a global approach was followed. The ulnar nerve was routinely identified, released from the tunnel, and protected. Broad medial and lateral full-thickness soft tissue flaps were elevated, and the elbow joint was exposed. The coronoid process fracture was addressed first, according to the Regan-Morrey classification.^{8 (link)} Fixation of the coronoid process was performed for type II and III fractures, while type I coronoid tip fractures did not require fixation. The radial head fracture was then repaired or replaced with an artificial implant according to the fracture pattern and bone quality.
Once bony reconstruction was complete, we used a Kirschner-wire (K-wire) to drill a tunnel under the guidance of an aim-device (cruciate ligament reconstruction guide) from the lateral aspect into the distal humerus along the rotation axis of the ulnohumeral joint. The rotation axis could be determined by direct visualizing of the anatomic center of the capitellum and the origin of the medial collateral ligament (MCL). After the tunnel was created, the lateral collateral ligament (LCL) complex injury was repaired by direct suture or reattached to the lateral epicondyle. Most LCL injuries presented as an avulsion fracture over the lateral epicondyle. Anatomical fixation of the LCL could be fulfilled through reattaching the avulsion fragment back to the fracture site using one or two anchor sutures. The MCL complex was not repaired whether residual elbow instability existed or not.
Subsequently, an IJS, as described by Orbay et al, was prepared.^{6 (link)} The IJS was created from a 2.4 mm K-wire with a figure-of-eight formed first on the blunt end to accept two 3.5 mm screws and washers for attachment to the ulna. The axis portion was established by making a sharp bend at the proper location and then cut to the appropriate length. The IJS was applied and attached to the proximal ulna with two 3.5 mm screws and washers while the elbow was in 90 flexion with an anatomic concentric reduction position. Restoration of elbow flexion/extension, pronation/supination, and stability in all directions were assessed under fluoroscopic guidance before wound closure.