Complications After Elbow Arthroscopy for Elbow Osteochondritis Dissecans

Positioning

Inappropriate positioning can cause neuropraxia, inadequate visualization, break in sterility, and prolonged operative time because of repositioning and difficulty of the case. ^{, ,} Depending on surgeon preference and procedure requirements, the patient can be positioned supine, lateral, or prone (see Chapter 39 ).

The prone position is preferred by some surgeons because of easy access to both the anterior and posterior elbow via arthroscopy and the reduced risk of breaking sterility if a finger trap device is required, as used in the supine position. Complications from poor padding and positioning can lead to ventilation and neurovascular compromise to extremities. With the patient prone, the face must be well padded and the airway secured. Chest rolls help lift the chest and abdomen from the table and thus decrease the pressure needed to ventilate. The knees and feet should be well padded at their pressure points. The nonoperative arm can be placed over a well-padded arm board with special attention to the ulnar nerve, or tucked at the patient’s side. The operative arm is draped over a well-padded arm board along the side of the table. It is recommended to check pulses in all four extremities after positioning. Once sterile draping is completed, it is recommended to place a stack of rolled towels under the operative arm to allow the elbow to flex to 90 degrees and align the humerus in the coronal plane of the patient’s body. ^{, ,} The greatest disadvantage to this position is converting to an open surgical approach should it be required.

A lateral decubitus position has several advantages and disadvantages when compared with the prone and supine positions. The lateral position is recommended over prone when there is concern for airway management because of extreme body habitus or compromised lung capacity. Plus, it is easier to convert to an open procedure, particularly if a posterior approach is indicated, because more shoulder mobility is attainable. Compared with supine positioning, lateral positioning provides equal access to the anterior and posterior compartments of the elbow, and the upper arm has a stable platform that prevents motion during the procedure. Conversely, the lateral position is problematic in very small patients, such as gymnasts, because of difficulty positioning the patient and maintaining access to the elbow. Similar complications related to airway and neuropraxia can occur with this positioning, particularly if awkward upper extremity positioning stresses the brachial plexus. In the lateral decubitus position, the patient is positioned on his or her side on an inflatable beanbag. An axillary roll is placed below the axilla, with the operative extremity placed in an arm holder or over a padded horizontal post. As described with the prone position, the same care is needed to protect and secure the face and airway, as well as pad the knees and elevate the feet. It is recommended to check pulses in all four extremities after positioning.

Supine position can be performed in either the cross-body or suspended position. Supine position, in general, has decreased positioning complications related to airway and posture-related neuropraxias compared with the lateral and prone positions. Nonetheless, pressure points should still be padded, airway secured, knees padded, and feet elevated. For the supine cross-body position, there are various commercially available arm holders. This position is safe and effective and provides easy conversion to an open procedure if an arthrotomy is required without breaking sterility or repositioning. However, the elbow is not rigidly secured against a post, which can make complex procedures more difficult. With the arm suspended in the supine position, the hand or wrist is hung from a traction device, (i.e., finger traps), and thus carry the same issues with elbow instability during the procedure. In addition, the supine suspended position poses the risk of the arthroscope withdrawing from the portal unexpectedly during trocar switching. Lastly, this position provides poor access to the posterior compartment of the elbow, given the a near vertical alignment, which makes arthroscopy difficult. ^, All things considered, being proficient in all three positions allows the surgeon the flexibility to adjust the surgical environment to best treat the lesion and patient.

Peripheral Nerve Injury

Peripheral nerve injury has a higher incidence in the elbow after arthroscopy than other joints because of the proximity of the neurovascular structures to the working field and portals ( Fig. 40.2 ). ^{, , ,} Although some argue that the incidence is underreported, the prevalence is variable (0%–14%) ^, and ranges from transient sensory neuropraxia to complete transection. Desai et al. reported on 222 nerve injuries referred after elbow arthroscopy. In this survey, hand surgeons reported that almost half of these injuries required surgical intervention, including grafting, tendon or nerve transfer, or nerve repair. Of these interventions, 77% had only partial or no motor recovery. Nonetheless, the majority of nerve injuries reported in the literature are transient sensory neuropraxias, rather than complete paralysis. ^, The most commonly injured nerve is the ulnar nerve, followed by the superficial radial nerve, posterior interosseous nerve (PIN), anterior interosseous nerve, and medial antebrachial cutaneous nerve. ^{, ,}

Knowledge of the periarticular neuroanatomy of the elbow, its relationship to portal locations, and its deviations after saline insufflation and elbow positioning are keys to preventing nerve complications. The portals and bony and soft tissue landmarks should be marked with attention to the location of the ulnar nerve and if subluxation occurs in flexion. To some surgeons, prior subcutaneous nerve transposition is a relative contraindication to arthroscopy, whereas sub- or intramuscular transposition is an absolute contraindication to elbow arthroscopy. In the presence of previous ulnar nerve transposition, the surgeon should visualize the ulnar nerve before making the anteromedial portal. Before portal placement, the elbow should be flexed to 90 degrees and injected with 20 to 30 mL saline through the direct lateral soft spot. ^, Miller et al. demonstrated that elbow flexion and capsule distention increased the nerve-to-bone distance to an average of 1 mm for the ulnar nerve, 6 mm for the radial nerve, and 12 mm for the median nerve. However, the capsule-to-nerve distances were relatively unchanged with saline insufflation (ulnar nerve on the capsule, radial nerve and median nerve within 6 mm of the capsule). It was also demonstrated that elbow extension negates the protective effect of saline insufflation.

Nerve injury can occur unrelated to direct trauma to the nerve. Anesthesia can temporarily impact nerve function. Arthroscopy can be performed under either general or regional anesthesia. Although a regional block can be performed preoperatively, it is recommended that it be considered after completion of an intact nerve exam in the recovery room. These procedures are dependent on the comfort level of the anesthesiologist, and the use of ultrasound can reduce the morbidity associated with application. Other patient-related risk factors such as RA or presence of significant elbow contractures have a higher risk of having nerve injury after elbow arthroscopy. This is believed to be a traction injury from the increased range of motion (ROM) after contracture release. ^{, ,}

Inadequate Visualization and Access

Inadequate visualization and access to the entire capitellum will make the case more challenging and can lead to poor surgical technique and potentially iatrogenic complications, and thus poor patient outcomes. A standard five-portal technique is usually suitable for the surgeon to assess the entire capitellum and joint and provide an appropriate working field for the majority of treatments for capitellar OCD. The anteromedial portal provides good visualization of the capitellum, whereas the remaining portals are working portals and used for visualization of potential loose bodies (anterolateral, direct lateral, posterolateral, posterior central). Other accessory portals can be used to improve visualization. Loose bodies commonly are found in the olecranon fossa, posterior gutters, and anterior to the radioulnar joint. ^{, ,} Flexion and extension of the elbow can also help with visualization of the capitellum.

Portal placement should start with skin incision only and then blunt dissection with the trocar through the capsule. The presence of fluid indicates intraarticular position if saline was insufflated intraarticularly at the start of the case. The anterolateral portal is commonly the first portal placed but has the smallest margin of safety because of its proximity to the PIN. To aid appropriate placement, this portal can be placed before saline insufflation to avoid alteration of palpable landmarks. The anterolateral portal is placed anterior to the radiocapitellar joint, but erring more proximal can reduce injury to the PIN, which lies distally. Next, the anteromedial portal should be placed 1 to 2 cm distal and 1 to 2 cm anterior to the medial epicondyle. Another technique that can be used to ensure suitable position is an inside-out technique that involves placing the camera in the anterolateral portal and traveling medially through the flexor-pronator mass to the desired anteromedial portal position. The surgeon can then incise at the location of the light and tented skin. The direct lateral portal is created at the soft spot at the center of a triangle created by the radial head, olecranon, and lateral epicondyle. The portal allows good access for treatment of the capitellum. The direct posterior portal is located 2 to 3 cm proximal to the proximal edge of the olecranon. A working space has to be created along the posterior humerus to remove the posterior fat pad for visualization of potential loose bodies in the joint. Be careful to keep the shaver turned away from the direction of the ulnar nerve. To further look for hidden loose bodies once the space is created, the posterolateral portal can be placed on the posterolateral surface of the olecranon at its proximal edge. ^, Avoid extensive dissection posteriorly because the capitellum is supplied by two end-nutrient arteries that enter posteriorly. ^{, ,} A distal ulnar portal can also be useful for OCD lesions that extend to the posterior capitellum. The portal is created 3 to 4 cm distal to the radiocapitellar joint, and a blunt trocar is maneuvered proximally along the lateral border of the ulnar to the joint. In the end, the surgeon should never settle for incomplete visualization and access if he or she feels too limited with the arthroscope. The surgeon should be prepared for a lateral arthrotomy, if necessary. The Kocher approach to the lateral elbow between the anconeus and the extensor carpi ulnaris is most commonly used. ^,