Coronoid fractures and traumatic elbow instability

The coronoid process is key to concentric elbow alignment. Malalignment can contribute to post-traumatic osteoarthritis. The aim of treatment is to keep the joint aligned while the collateral ligaments and fractures heal. The injury pattern is apparent in the shape and size of the coronoid fracture fragments: (1) coronoid tip fractures associated with terrible triad (TT) injuries; (2) anteromedial facet fractures with posteromedial varus rotational type injuries; and (3) large coronoid base fractures with anterior (trans-) or posterior olecranon fracture dislocations. Each injury pattern is associated with specific ligamentous injuries and fracture characteristics useful in planning treatment. The tip fractures associated with TT injuries are repaired with suture fixation or screw fixation in addition to repair or replacement of the radial head fracture and reattachment of the lateral collateral ligament origin. Anteromedial facet fractures are usually repaired with a medial buttress plate. If the elbow is concentrically located on computed tomography and the patient can avoid varus stress for a month, TT and anteromedial facet injuries can be treated nonoperatively. Base fractures are associated with olecranon fractures and can usually be fixed with screws through the posterior plate or with an additional medial plate. If the surgery makes elbow subluxation or dislocation unlikely, and the fracture fixation is secure, elbow motion and stretching can commence within a week when the patient is comfortable.</p

Arthroscopic localization of the ulnar nerve behind the medial capsule is unreliable

Purpose: Ulnar nerve injury is the most common neurologic complication of elbow arthroscopy. The purpose of this cadaveric study was to quantify the ability of surgeons to locate the ulnar nerve behind the posteromedial capsule during elbow arthroscopy using sole arthroscopic vision. Methods: Twenty-one surgeons were asked to pin the ulnar nerve at the medial gutter and the posteromedial compartment using arthroscopic visualization of the medial capsule only. Pinning of the ulnar nerve was performed from extra-articular. Then, the cadaveric specimens were dissected and the shortest distances between the pins and ulnar nerve measured. Results: Median pin-to-nerve distances at the medial gutter and posteromedial compartment were 0 mm (interquartile range [IQR], 0-3 mm) and 2 mm (IQR, 0-6 mm), respectively. The ulnar nerve was pinned by 11/21 surgeons (52%) at the medial gutter, and 7/21 surgeons (33%) at the posteromedial compartment. Three of 21 surgeons (14%) pinned the ulnar nerve at both the medial gutter and the posteromedial compartment. Surgeon's experience and operation volume did not affect these outcomes (P &gt;.05). Conclusions: Surgeons' ability to locate the ulnar nerve behind the posteromedial capsule using sole arthroscopic visualization, without external palpation, is poor. We recommend to proceed carefully when performing arthroscopic procedures in the posteromedial elbow, and identify and mobilize the ulnar nerve prior to any posteromedial capsular procedures