Elbow Arthroscopy (Cadaver)

Abstract

Elbow arthroscopy is a technically demanding procedure but it is very useful to evaluate the entire elbow joint for pathology with minimal surgical exposure and faster recovery than a traditional arthrotomy. The neurovascular structures of the elbow joint are in close proximity to the joint, thus there is a risk of injury to these structures, so care must be taken to fully understand elbow anatomy and to be prepared for aberrations. Elbow arthroscopy can be used diagnostically, as in this video article, or to surgically treat a variety of conditions including ligamentous tears, loose bodies, capsular stiffness, osteochondritis dissecans of the elbow, osteophyte debridement, and lateral epicondylitis. A patient with a previous ulnar nerve transposition is a relative contraindication to elbow arthroscopy, as there is a high risk of injury to the ulnar nerve during portal placement.

Case Overview

Questions to Ask While Conducting the History:¹

• Is there a history of repeated elbow dislocations?
• Is there elbow instability? What is the timing?
• Is there pain with range of motion?
• Is there complete range of motion?
• What articulation is involved? It can be the hinge joint or the proximal radioulnar joint.
• Was there predisposing trauma?
• Has there been previous elbow trauma or surgery?
• Does the elbow displace? In what direction?
  • Posterolateral rotatory displacement is the most common direction.
  • Anterior displacement may be seen with olecranon fractures.
  • Valgus instability may be seen with post-traumatic rupture of the medial collateral ligament (MCL) or radial head fractures; it may also be seen in athletes with repetitive stress and overload that diminishes or ruptures the anterior band of the MCL.
• Varus instability may be seen with LCL complex disruption.
  • What is the degree of displacement?
  • There can be posterolateral rotatory subluxation with pivot-shift testing (Stage 1)
  • There can be incomplete dislocation with the coronoid perched under the trochlea (Stage 2)
  • There can be complete dislocation with the coronoid behind the humerus (Stage 3)
• Is there recurrent clicking, snapping, clunking, or locking of the elbow?

Physical Exam

Tips for Conducting the Physical Exam:¹

• Visually examine for gross deformity, skin lesions, erythema, or effusion.
• Palpate the humerus, elbow joint, radius, and ulna. Looking for tenderness indicative of occult fracture.
• Observe and document elbow range of motion.When evaluating elbow motion, the examiner should observe for any crepitus, pain, or mechanical block symptoms, which could indicate cartilage irregularities or loose bodies. If the elbow has restricted motion in flexion or extension, a soft end point might suggest effusion, soft-tissue swelling, or capsular tightness. Conversely, a firm end point could indicate an osteophyte or loose body causing a mechanical block. Pain at the end point of flexion and extension, particularly localized to the medial olecranon, may be indicative of degenerative changes associated with chronic valgus extension overload and posteromedial impingement.⁶
• Assess instability at 0 and 30 degrees of flexion.
  • At 30 degrees of flexion, MCL complex is primary stabilizer. Instability only at 30 degrees indicates MCL pathology.
  • In full extension other bony and soft tissue restraints exist. Instability here indicates more extensive injury, with possible anterior and posterior capsule involvement.
• Observe elbow supination and pronation.
• Special tests:
  • Lateral pivot-shift apprehension test. Patients supine with arm overhead, forearm supinated, hold distal to elbow and near the wrist and apply valgus and compressive forces while flexing. This will recreate symptoms and cause a sensation that the elbow is about to dislocate. With flexion, the radius and ulna should reduce with a clunk onto the humerus.
  • Milking Maneuver is used to assess the integrity of the anterior bundle of the MCL. During this test, the patient’s elbow is flexed beyond 90 degrees, and the examiner pulls on the patient’s thumb while the forearm is supinated and the shoulder is forward-flexed. A positive test is indicated by a feeling of apprehension, instability, and medial elbow pain.⁶
  • The moving valgus stress test detects ulnar collateral ligament (UCL) tears. During this test, the patient’s shoulder is abducted to 90 degrees, and the elbow is maximally flexed while applying a modest valgus stress. The elbow is then quickly extended to 30 degrees while maintaining the valgus stress. A positive test is indicated by pain experienced between 120 and 70 degrees of elbow flexion, which correlates with the late cocking and early acceleration phases of throwing.⁶
  • Valgus Stress Test. This test evaluates the MCL by applying a valgus force to the elbow flexed at 20–30 degrees. A positive result is indicated by pain or increased laxity compared to the opposite side.⁶
  • Varus Stress Test. The varus stress test assesses the lateral collateral ligament (LCL) by applying a varus force to the elbow flexed at 20–30 degrees. Pain or increased laxity signifies a positive test.⁶
  • Posterolateral Rotary Drawer Test. This test assesses posterolateral rotatory instability. Elbow is positioned in approximately 40 degrees of flexion. Then anterior to posterior force applied to the lateral aspect of proximal radius and ulna. This maneuver attempts to translate the forearm away from the humerus on the lateral side, pivoting around the intact medial ligaments. Subluxation or apprehension indicates a positive result.⁶