General Principles of Elbow Arthroscopy

Introduction

The indications for elbow arthroscopy have advanced remarkably in the past 30 years. In the past, the arthroscope was an instrument rarely used in the elbow. Originally, it was described as a tool used for diagnostic purposes, removal of loose bodies, synovectomy, and lysis of adhesions. Thorough knowledge of anatomy and increasing familiarity with arthroscopy has allowed surgeons to push the envelope to expand indications and advance techniques to treat a myriad of elbow conditions arthroscopically. Elbow arthroscopy is now routinely used by skilled arthroscopists and taught in sports medicine and upper extremity fellowships. It is routinely used for the treatment of lateral epicondylitis, osteochondritis dissecans (OCD), osteoarthritis and osteophyte resection, radial head resection, plica excision, septic arthritis, and contracture release. Pioneers in the field continually develop innovative ideas and new surgical techniques to treat a growing list of conditions, including arthroscopic reduction and fixation of fractures, ligament repair, ulnar nerve decompression, and elbow arthroplasty.

Diagnostic arthroscopy, loose body removal, and treatment of lateral epicondylitis will always remain basic techniques of elbow arthroscopy. They are some of the most common and rewarding arthroscopic procedures in the elbow. They allow the novice arthroscopist to gain familiarity and confidence in the elbow and can be used as a stepping stone to more advanced procedures. As one becomes more comfortable and facile using the arthroscope in the elbow joint, it allows the treating surgeon to use the scope as a diagnostic tool to confirm instability patterns, assess articular cartilage congruence during fracture reduction, and confirm stability after fracture fixation or ligament reconstruction.

As with all elbow arthroscopic procedures, a three-dimensional understanding of the neurovascular anatomy is paramount for safety and success. A concrete preoperative plan is essential. The surgery should be performed with speed and precision, with adjustments made to account for intraoperative findings, as swelling will increase throughout the case.

This chapter will highlight basic principles of elbow arthroscopy, indications and contraindications, patient positioning, arthroscopic portals, and the key steps to perform during the procedure.

Anatomy

The elbow is a complex joint that allows flexion and extension through the ulnohumeral articulation and pronation and supination at the radiocapitellar joint. Primary stability is provided by the medial collateral ligament (MCL) complex, the lateral collateral ligament (LCL) complex, and the ulnohumeral articulation. Dynamic stability is provided by the brachialis, triceps, and the mobile wad.

A thorough understanding of the three-dimensional neurovascular anatomy is crucial to safely perform elbow arthroscopy. All described portals allow access to the joint through safe zones ( Fig. 18.1A,B ). In general, proximal portals are safer than distal portals because they are farther away from the neurovascular structures. The radial nerve and posterior interosseous nerve (PIN) are at risk on the lateral side of the elbow, the median nerve is at risk on the anteromedial side, and the ulnar nerve is at risk on the posteromedial side.

Surgical Indications

The indications for elbow arthroscopy include removal of loose bodies, synovectomy for inflammatory arthritis, debridement of septic arthritis, debridement of osteoarthritis, contracture release, treatment of osteochondral defects, selected fractures, lateral epicondylitis, and ligament repairs. Elbow arthroscopy is also indicated for diagnostic purposes. Diagnostic arthroscopy can be used to confirm intraarticular pathology and to rule out concomitant pathology during open elbow procedures. Loose bodies can develop secondary to arthritis, trauma, or synovial chondromatosis. Arthroscopy remains an excellent tool to safely remove the loose bodies through minimally invasive means. Cohen et al. showed that lateral epicondylitis can be safely and thoroughly treated with arthroscopic extensor carpi radialis brevis (ECRB) release. Arthroscopy can be used for treatment of OCD with a displaced cartilage cap. It can be used for arthroscopic fixation of the osteochondral fragment, debridement of the cartilage cap, and microfracture of the bed or debridement of the lesion prior to an open grafting procedure. Arthroscopy is an excellent tool for resection of osteophytes in the arthritic elbow, resection of the radial head in radiocapitellar arthritis, and capsular release in the stiff elbow. Arthroscopic repair of the LCL complex can be safely performed to treat posterolateral elbow rotatory instability (PLRI) after elbow dislocation. Additional indications include arthroscopic fixation of select fractures, triceps tendon repairs, confirmation of instability patterns prior to ligament repair or reconstruction, to remove hematoma or incarcerated cartilage fragments from irreducible elbow dislocation, arthroscopic assistance with fracture reduction, and to confirm articular cartilage congruence during open reduction internal fixation.

Contraindications

The only true contraindication to elbow arthroscopy is distortion of the normal anatomy that would preclude a safe arthroscopic procedure. The potential for neurovascular injury in elbow arthroscopy is higher than in other joints because of the proximity of the neurovascular structures to the portals and working field. When the anatomy is distorted due to congenital anomalies, previous trauma, or previous surgery, and the exact location of the neurovascular structures is not known, elbow arthroscopy should not be performed. Prior ulnar nerve subcutaneous transposition is not necessarily a contraindication if the location of the ulnar nerve can be identified. Prior ulnar nerve submuscular transposition is generally considered a contraindication. The risk of nerve injury is too great in these circumstances. In these instances, the location of the neurovascular structures can be determined by dissection through small incisions. Once the location of the nerves and arteries is confirmed, elbow arthroscopy can be safely performed.

Patient History

Patients will predominantly complain of pain in the elbow. Epicondylitis will typically be present with medial or lateral pain with no preceding trauma. The pain is worse with lifting, especially with the wrist extended. Patients with loose bodies in the elbow will often complain of intermittent pain and feelings of clicking, catching, or locking in the joint. Pain, swelling, and stiffness are commonly reported with synovitis. Patients with arthritis may report stiffness and a gradual loss of motion, most commonly loss of terminal flexion or extension. A traumatic injury may precede the symptoms, although very often there is no history of trauma. It is important to inquire about any previous treatment and previous surgery for ulnar nerve decompression or transposition.

Pertinent Physical Examination Findings

Inspect the elbow for any scars or obvious deformity. Surgical scars on the medial side may alert the orthopedic surgeon to previous ulnar nerve surgery. Elbows with synovitis may have an effusion with boggy swelling in the posterolateral gutter. ROM should be measured and documented, including flexion, extension, and pronosupination, and compared to the contralateral side. If a loss of motion is discovered, the quality of the end point should be evaluated. Elbows with arthritis and osteophytes may have a firm end point at terminal flexion and extension due to osteophyte impingement. A soft end point suggests synovitis or capsular contracture. Palpate the radiocapitellar joint and lateral gutter for palpable loose bodies. On the medial side, the ulnar nerve and medial epicondyle should be palpated during flexion and extension to evaluate for a subluxating ulnar nerve. A subluxated or dislocated ulnar nerve can be found in 16% of the normal population. It is crucial to know the location and status of the ulnar nerve prior to any arthroscopic procedure to avoid iatrogenic injury to the nerve. Assess stability on the medial and lateral sides of the elbow with varus and valgus stress testing. Palpation of the radiocapitellar joint during simultaneous valgus load and pronation/supination of the forearm can assess for crepitus and arthritis or palpable loose bodies in the lateral gutter. Finally, a thorough neurovascular exam should be performed and documented. It is important to pay particular attention to the function of the ulnar nerve and PIN, as these nerves may be compressed when synovitis is present.