Ulnohumeral Arthroplasty






CHAPTER PREVIEW


CHAPTER SYNOPSIS:


Degeneration of the ulnohumeral joint is rare but can occur after trauma, through heavy labor, or via inflammatory arthropathies. Treatment options range from arthroscopic debridement to linked total elbow arthroplasty. Selecting the right treatment for each individual patient requires not only an understanding of the pathology but also of the demands placed on the joint by the patient.




IMPORTANT POINTS:





  • Maintenance or restoration of elbow stability is crucial for elbow function.



  • Total joint arthroplasty should be reserved for elderly low-demand patients in most circumstances.



  • Joint debridement and interposition can extend the functional life of the ulnohumeral joint while having little to no impact on delayed implant arthroplasty.



  • Preservation of extensor mechanism function should guide the selection of surgical techniques.



  • Complications in ulnohumeral arthroplasty are more common than for other joints.





CLINICAL/SURGICAL PEARLS:





  • Consider a linked implant arthroplasty only when other options are not appropriate because of instability or severe bone loss.



  • Always consider the preoperative function of the ulnar nerve and have a low threshold for decompression or transposition of the nerve.



  • When choosing a surgical option, consider what the revision would be to make sure no bridges are burned.



  • A stable stiff elbow is better than an unstable elbow.





CLINICAL/SURGICAL PITFALLS:





  • Avoid surgical approaches that detach the extensor mechanism.



  • Release the ulnar nerve if severe loss of elbow flexion is to be corrected.


    Local antibiotics, either in cement or as regional infusions, should be used to limit infection in implant arthroplasty.



  • Whenever possible, restore or repair stabilizing structures.





VIDEO:


N/A




INTRODUCTION


The goal of elbow arthroplasty, whether accomplished through resurfacing or prosthetic replacement, has been to provide a painfree stable joint with a functional range of motion. Resection arthroplasty has been performed for more than 200 years, providing effective pain relief but resulting in high rates of instability. In an effort to preserve stability, the next evolution in elbow arthroplasty resected less bone and interposed fascia, fat, or skin to resurface the joint space. Arthrodesis remains an option, particularly for younger patients, but the associated complication rates are high and the functional limitations are severe. The first modern elbow replacement was described in 1972 by Dee, who used a constrained hinged cemented prosthesis that did not accurately replicate elbow motion. From his efforts, we learned of the limitations of a rigid hinge in causing component loosening, bone loss, and particulate debris. Since that time, our understanding of the mechanics of the elbow has increased dramatically. Through early trial-and-error failures, we have arrived at the modern “sloppy” hinge, which provides both motion and stability by more closely replicating elbow biomechanics. However, the most popular designs today are not truly anatomic. It is likely that the future of arthroplasty will place more emphasis on native tissues for stability and highly contoured prostheses to more closely mimic the nascent articulations.


Relative to other joints, the elbow typically is spared the sequelae of osteoarthritis (OA) and inflammatory arthritis. Even in cases of posttraumatic arthritis, many patients are able to function and compensate with radiographically compromised articulations. Most patients with painful degenerative arthritis of the elbow are middle-aged manual laborers presenting with limitations in motion and painful terminal extension in their dominant arm. Posttraumatic arthritis can present similarly, although bony deformity and more significant limitations in motion are common. Patients with posttraumatic arthritis present a difficult reconstructive challenge because they often are younger and have bony and soft tissue compromise. Chronic neurovascular injuries can also reduce postreconstructive outcomes.


The most common indication for elbow arthroplasty remains rheumatoid arthritis (RA). As many as two thirds of patients with RA suffer from arthritis of the elbow. Patients with inflammatory arthritis tend to have medical comorbidities that limit their activity levels and therefore represent excellent candidates for arthroplasty procedures in general. However, bone quality and soft tissue envelope durability can lead to complications. Optimization of medical management, particularly with new disease-modifying drugs, is necessary before consideration of surgical options for patients with inflammatory arthritis.


Regardless of the cause of the condition, patients with limitations in elbow function present with either loss of motion, pain, instability, or a combination of the three. Radiographs do not always correlate with the severity of symptoms and should not be used in isolation. Standard anteroposterior, lateral, and radiocapitellar views usually are sufficient. Classic findings in OA are joint space narrowing, subchondral sclerosis, and osteophyte formation. For patients with RA, joint space erosions, periarticular osteopenia, and a relative paucity of osteophyte formation are typical findings. Varus and valgus deformities might be present in patients with OA and in patients with RA. A radiographic classification system has been defined by Larsen and colleagues. For patients with posttraumatic arthritis, particularly in the presence of exuberant heterotopic ossification, computed tomography (CT) might be useful for preoperative planning. CT might also be helpful if fracture union is in question. Magnetic resonance imaging rarely is indicated.


If previous or ongoing infection is suspected, routine laboratory studies, such as white blood cell count, erythrocyte sedimentation rate, and C-reactive protein, should be conducted. Depending on the index of suspicion, joint aspiration might be indicated. In cases of RA, a leukocytosis of 50,000 cells/mm 3 can be observed without the presence of infection.




MANAGEMENT


All patients with degenerative elbow complaints deserve adequate courses of nonsurgical treatment. The mainstay of treatment is nonsteroidal anti-inflammatory drugs, splinting, and intraarticular injections. Physical or occupational therapy can be particularly helpful for patients with weakness and loss of motion. Increasing muscle tone and endurance might also be helpful in minimizing subtle instability of the elbow. Patients with higher grades of instability can be treated with hinged braces.


Patients who fail to make progress or continue to have debilitating symptoms despite administration of the modalities listed previously can be considered for surgical intervention. Because the elbow is a multijoint articulation, each joint should be considered individually and cumulatively during preoperative planning. Arthritis of the proximal radioulnar joint and the radiocapitellar joint can be addressed with radial head replacement or resection. Ulnohumeral arthritis, either in isolation or in conjunction with arthritis in the other elbow joints, represents the most difficult reconstructive problem.


Ulnohumeral instability with no evidence of joint degeneration can be corrected with ligament reconstruction or repair, depending on acuity, which might prevent late degeneration in the same way that tightening the wheels on a car can limit tire wear. However, longstanding instability and even acute episodes of instability can lead to intraarticular chondral injury and subsequent degeneration. Stabilization procedures in patients with arthritic joints can paradoxically worsen symptoms as already-compromised joints are tightened.


Patients with early arthritis or arthritis marked primarily by osteophyte formation can be treated with joint debridement as an alternative to implant arthroplasty or interpositional arthroplasty. The joint alignment and architecture must be relatively preserved with painful limited extremes of motion predominating for the technique to be successful. Suvarna and Stanley looked at the olecranon fossa of eight patients with degenerative arthritis of the elbow and noted thickening of the bone and hypertrophy of the overlying soft tissues. Removing the hypertrophied bone allows greater motion and relieves the pain of bony impingement.


Similarly, patients with posttraumatic loss of motion can benefit greatly from arthroscopic or open releases and excision of any heterotopic bone. However, a small painless arc of motion can be converted to a larger painful range of motion if the release uncovers diseased segments of cartilage and bone loss. Nonetheless, patients might prefer the increase in motion even with the pain.


For some patients, the initial traumatic event might be sufficient to preclude primary fracture fixation. For others, because of age or associated comorbidities, primary arthroplasty might be the least invasive option with the most reliable results. Early use of the limb can be the greatest advantage of primary arthroplasty for the treatment of elbow fractures in such patients.


Preoperative planning must therefore include the patient, who should be made aware of the potential problems associated with ligament reconstruction or joint releases in the presence of arthritis. Primary joint replacement should be discussed as a possibility if the chondral damage is found to be severe intraoperatively. Other patient factors that should be considered include overall health, functional demands, age, hand dominance, previous operations and infections, potential compliance, and overall expectations.




SURGICAL ANATOMY AND APPROACHES


The elbow joint is made up of three articulations: the radiocapitellar joint, the ulnohumeral joint, and the proximal radioulnar joint. The hemispherical capitellum and concave radial head of the radiocapitellar joint allow flexion, extension, and rotation. The joint is stabilized by the lateral ulnar collateral ligament, the radial collateral ligament, and the annular ligament ( Fig. 19-1 ). The most important ligament on the lateral side is the lateral ulnar collateral ligament. The proximal radioulnar joint participates only in rotation. The ulnohumeral articulation has inherent stability because of the congruity and single plane of motion of the joint. As the joint is placed into more and more flexion, the bony structures, such as the coronoid, provide an increasing percentage to joint stability. In extension, soft tissue constraints predominate. On the medial side, the anterior band of the medial collateral ligament (MCL) is the most important for valgus stability, extending from the medial epicondyle of the humerus to the sublime tubercle of the ulna ( Fig. 19-2 ).




FIGURE 19-1


Lateral elbow ligaments. The lateral ulnar collateral ligament, the annular ligament, and the radial collateral ligament make up the lateral collateral ligament complex. The lateral ulnar collateral ligament is the most critical, protecting against posterolateral rotatory instability.



FIGURE 19-2


Medial elbow ligaments. The medial collateral ligament is a capsular thickening composed of three distinct bands: the anterior, posterior, and transverse. Of the three, the anterior band resists the majority of valgus load across the elbow. Although this ligament is critical in throwing athletes, its importance in the general population is less clear.


In 90 degrees of flexion, the triceps and biceps have a combined destabilizing effect because of their overall posteriorly directed vector. Otherwise, the remaining muscles that cross the elbow provide dynamic stabilization by compressing the joint.


The importance of triceps function, however, in the overall function of the elbow has led to the development of triceps-sparing approaches for joint exposure. Pierce and Herndon described a true triceps-preserving approach. The obvious advantage of such an approach is the lack of compromise of the extensor mechanism with the ability to mobilize the patients actively postoperatively. A posterior incision is made circumventing the olecranon medially. The ulnar nerve is identified and transposed anteriorly in a subcutaneous pocket. The joint is opened by subperiosteal dissection on the medial side, elevating the MCL off of the ulna. Approximately one-third of the flexor–pronator mass can be released from the medial epicondyle to facilitate exposure. The interval between the brachialis and the medial head of the triceps is developed, with subperiosteal reflection of the medial head. Dislocation of the ulnohumeral joint can then easily be accomplished by hyperpronation and flexion ( Fig. 19-3 ). The medial window provides adequate exposure of the proximal ulna for canal preparation. The canal can be opened with the use of an awl or a high-speed burr and can then be rasped to the appropriate size in preparation for implantation. Correct entry point selection is critical; a proximal starting point will limit flexion, and a distal one will limit extension. The Kocher approach is used for exposure of the radiocapitellar joint and distal humerus. Subperiosteal release of the lateral collateral ligament (LCL) complex and one-third of the extensor origin from the lateral epicondyle with elevation of the lateral head of the triceps defines a lateral window ( Fig. 19-4 ). The radial nerve need not be seen unless a more proximal exposure is necessary. The radial head is excised if warranted, and the distal humeral canal can be prepared through the lateral window. Supination of the forearm delivers the distal humerus into the wound.




FIGURE 19-3


Triceps-preserving approach: medial window. After ulnar nerve transposition, the medial collateral ligament and the flexor–pronator mass are released from the medial epicondyle. The triceps muscle is retracted laterally, while the forearm is forced into hyperpronation. This dislocates the elbow and provides access to both the distal humerus and the proximal ulna.

(Adapted from Pierce TD, Herndon JH: The triceps preserving approach to total elbow arthroplasty. Clin Orthop Relat Res 354:144−152, 1998.)



FIGURE 19-4


Triceps-preserving approach: lateral window. An extended Kocher approach between the anconeus and extensor carpi ulnaris is used to expose the radial column of the humerus and the radial head. The lateral collateral ligament origin is released from the lateral epicondyle. Proximally, the triceps is mobilized medially off the lateral intermuscular septum.

(Adapted from Pierce TD, Herndon JH: The triceps preserving approach to total elbow arthroplasty. Clin Orthop Relat Res 354:144–152, 1998.)


After implantation, the medial and lateral windows are closed to cover the condyles and the prosthesis. Although not described in their original technique, the muscle origins and ligament attachments can be repaired to bone by using transosseous sutures or suture anchors. The results with this approach to 10 elbow arthroplasties showed good strength in nine patients with no triceps avulsions, deep infections, ulnar nerve neuropathies, or wound complications. Range of motion was from 15 to 135 degrees, on average. The approach initially relies on the inherent stability of the implant while the soft tissue envelope reconstitutes.


Bryan and Morrey advocate a triceps-reflecting approach that maintains the triceps in continuity with the periosteum of the dorsal ulna. The initial exposure is similar to that of the triceps-preserving approach, including ulnar nerve transposition. However, the triceps is then reflected subperiosteally from a medial-to-lateral direction, cutting Sharpey’s fibers but maintaining continuity of the triceps tendon with the periosteum of the ulna. To minimize tension on the flap, the procedure is performed with the elbow at 20 degrees of flexion. We use this approach not only for arthroplasty but also for intraarticular distal humerus fractures. For added visualization, the olecranon tip can be excised. The anterior portion of the MCL is released from the humerus, allowing the elbow to dislocate. After implantation, the ligament can be repaired to bone, as with the triceps-preserving approach. Triceps repair is accomplished via transosseous #5 nonabsorbable sutures ( Fig. 19-5 ). Bryan and Morrey reported no episodes of extensor disruption occurring in 49 consecutive patients treated with this approach.




FIGURE 19-5


Repair of the triceps insertion. Three drill holes are made in the proximal ulna, and the triceps insertion is secured to bone with heavy nonabsorbable sutures.

(Adapted from Celli A, Arash A, Adams RA, et al: Triceps insufficiency following total elbow arthroplasty. J Bone Joint Surg Am 87:1957–1964, 2005.)


O’Driscoll combined the medial and lateral triceps-reflecting approaches into the triceps-reflecting anconeus pedicle approach. The combined approach reflects a triangle of periosteum with the triceps and anconeus, but unlike the triceps-preserving or triceps-sparing approaches, it does result in discontinuity of the extensor mechanism. In a review of the arthroplasty literature, Little and colleagues found that techniques that detach the extensor mechanism had the highest rates of postoperative triceps disruption at 11%. In cases in which the triceps was kept in continuity with the periosteum of the ulna, the avulsion rate was only 3%.


An olecranon osteotomy provides excellent exposure and relies on the more reliable bone-to-bone healing. However, fixation of the osteotomy with the implants in place can be challenging, introducing the potential complication of nonunion.




SURGICAL OPTIONS: JOINT DEBRIDEMENT


Often, the initial presentation of elbow arthritis is limited motion with pain in the extremes of motion. Radiographs typically show encroachment of osteophytes over the olecranon and coronoid fossae, with loss of terminal extension and flexion, respectively. Osteophyte impingement and intraarticular loose bodies also can be sources of pain and mechanical symptoms beyond the degeneration of the articular-bearing surfaces themselves. Kashiwagi described a triceps-splitting technique for joint debridement, relying on fenestrating the distal humerus to gain access to the anterior elbow. Various modifications of the technique, both open and arthroscopic, have been described. In general, all debridement techniques achieve the same goals: removal of any impinging osteophytes and loose bodies. The Outerbridge-Kashiwagi (O-K) technique, however, does not allow adequate access to the radiocapitellar joint. An arthroscopic technique likewise might not be appropriate in cases with large osteophytes or heterotopic ossification. Manipulation with the patient under anesthesia or either open or arthroscopic releases can be performed if capsular contracture persists after debridement.


The best candidate for joint debridement is the patient with normal or near-normal articular surfaces, loss of motion and pain in terminal extension, and ossification of the olecranon fossa. In a consecutive series of 43 patients, Forster and colleagues identified three positive prognostic factors for patients treated with the O-K technique: symptoms of less than 2 years’ duration, severe preoperative pain requiring regular analgesics, and the presence of cubital tunnel syndrome. Patients with anterior loose bodies and patients with absence of preoperative locking symptoms tended to fare worse.


Patients with severely degenerated and deformed articular surfaces—from malunion, nonunion, OA, or inflammatory arthropathies—are not candidates for joint debridement. Patients with instability might benefit from joint debridement, but the instability should be addressed concomitantly to or before debridement.


Open Joint Debridement (Debridement Arthroplasty)


Technique


Position the patient supine with a hand table. Drape out to the axilla to allow for placement of a sterile tourniquet. Make sure that the patient is able to rotate the shoulder. Incise the skin from the lateral border of the pronator teres distal to the joint to 4 cm proximal to the olecranon, curving the incision 1 cm posterior to the medial epicondyle. Identify and protect the medial brachial and antebrachial cutaneous nerves just superficial to the fascia. The ulnar nerve is released and retracted with a moistened ¼-inch Penrose drain. Elevate the flexor–pronator origin subperiosteally and reflect the mass distally. A step-cut can be made in the tendon origin to allow Z-lengthening at the time of closure, particularly if the ulnar nerve is to be transposed submuscularly. Preserve the anterior bundle of the MCL (along with the humeral origin of the flexor carpi ulnaris, if necessary), and divide the remainder of the capsule anteriorly. Beware the median nerve and brachial artery just medial to the brachialis and biceps tendon and the posterior interosseous nerve just lateral to the brachialis muscle. Resect all osteophytes and remove any loose bodies. Take care not to release the sublime tubercle on the anteromedial corner of the proximal ulna so as not to detach the anterior band of the MCL. Place a small retractor to protect the ligament while resecting the medial osteophytes. This exposure should allow debridement of the coronoid and the radial fossae. Next, divide the posterior band of the MCL and retract the triceps to expose the olecranon and olecranon fossa. Remove the medial osteophytes.


To access the lateral side, divide the fascia of the triceps just lateral to the muscle and carry the dissection to bone. The lateral olecranon and fossa should be visible, and debridement of those areas can be accomplished. If necessary, a separate lateral Kocher-type approach can be used to address radial-sided pathologic abnormality if the medial approach alone is inadequate. Carry the dissection to the lateral column and elevate the common extensor origin off the lateral epicondyle with care not to disrupt the LCL. The triceps and anconeus are retracted together, facilitating exposure of the radial head and the posterior compartment while maintaining the innervation of the anconeus. Divide the LCL longitudinally anterior to the lateral ulnar collateral bundle, transecting the annular ligament. Remove any osteophytes from the radial head and radial fossa.


Repair the LCL and close the interval between the extensor carpi ulnaris and the anconeus. Use bone tunnels to reattach the common extensor origin. On the medial side, repair the flexor–pronator mass to bone through bone tunnels along the supracondylar ridge. Transpose the ulnar nerve anteriorly subcutaneously and stabilize the nerve with a fasciodermal sling from the flexor–pronator fascia.


Alternatively, we prefer a single posterior incision for both the medial and the lateral release for several reasons. The posterior incision minimizes risk to the medial cutaneous nerves; allows access to the medial column, lateral column, and triceps-splitting approaches; and can be used for total elbow arthroplasty (TEA) if debridement fails in the future.


Results


Oka and colleagues reported that in 38 elbows with primary OA treated with lateral, medial, or combined debridement with a minimum 2-year followup (average followup duration, 5.9 years), the arc of motion improved by 24 degrees. Initial gains continued to improve from 6 months to 1 year. Although no statistically significant difference was shown between the medial, lateral, or combined approaches, the authors did not take into account the bias in selecting each approach. Improvements in pain were also similar for each approach, with 29 patients reporting no pain and seven reporting slight pain. The remaining two patients who experienced moderate to severe pain had pain on the side opposite the approach, one medial and the other lateral, indicating that they would have benefitted from the combined approach.


After a mean followup duration of 121 months, Wada and colleagues had achieved an average 24-degree improvement in arc of motion by performing posteromedial debridement in 33 elbows, supplemented with a lateral approach in nine. Among the patients followed for more than 10 years, an average progressive loss of extension of 7 degrees occurred compared with extension at the 1-year followup, but no loss in flexion was noted. 85% of their patients were satisfied with their results.


Ulnohumeral Arthroplasty (Modified O-K Technique)


Technique


Place the patient supine with a sandbag under the scapula and a nonsterile tourniquet on the upper arm. Make a utilitarian posterior incision from approximately 10 cm proximal to the olecranon to 2 cm distal and down to the triceps fascia. Decompress or transpose the ulnar nerve if indicated. The triceps can then be elevated from medial to lateral until the olecranon fossa can be visualized, usually releasing approximately 25% of the triceps insertion. Alternatively, if the triceps is bulky, a triceps-splitting approach can be used. Remove any osteophytes and loose bodies from the posterior compartment. Osteotomize the tip of the olecranon, taking care not to disrupt the triceps attachment. Open the olecranon fossa with a trephine just larger than the fossa, angling the trephine in an anteroproximal direction to account for the angle of the distal humerus. Flex the elbow and remove the coronoid osteophytes with a 7-mm curved osteotome ( Fig. 19-6 ). Palpate through the fenestration to assess for anterior loose bodies, which should be removed. Cover exposed bone surfaces with bone wax. For postoperative pain control, Marcaine-soaked Gelfoam (Pfizer Inc., New York, NY) can be placed in the olecranon fossa. Close the triceps release with nonabsorbable suture through bone tunnels if more than 50% of the insertion has been compromised.




FIGURE 19-6


Ulnohumeral arthroplasty. The triceps tendon is reflected laterally in continuity with the ulnar periosteum (A) to expose the proximal ulna and the distal humerus. Alternatively, a triceps-splitting approach can be used. Removal of the olecranon tip facilitates exposure and removes a potential cause of bony impingement in extension. A trephine is used to open the olecranon fossae and allow access to the anterior joint compartment (B). The coronoid osteophyte is excised (C) to prevent impingement in terminal flexion, and any loose bodies are removed.

(Adapted from Morrey BF: Primary degenerative arthritis of the elbow: Treatment by ulnohumeral arthroplasty. J Bone Joint Surg Br 74:409–413, 1992.)


Results


Antuna and colleagues presented the results of a mixed cohort of patients who had undergone the O-K procedure or Morrey’s modification of the O-K procedure with or without a column procedure and capsular release with a minimum 24-month followup. Improvements in range of motion averaged approximately 10 degrees each in flexion and extension, with no change in pronation or supination. Subjectively, of 46 patients with treated elbows, 20 felt much better, 14 felt better, 8 felt the same, and 4 felt worse than preoperatively. Of patients, 59% experienced recurrence of the coronoid and olecranon fossae osteophytes but to a lesser degree than preoperatively. Ulnar nerve symptoms occurred in 13 patients. Based on their experience, the authors recommend not manipulating the elbow during the early postoperative period unless a cubital tunnel release with or without transposition has been performed. They currently routinely release the ulnar nerve if the preoperative flexion is less than 100 degrees or if any preoperative nerve symptoms exist, regardless of severity.


At a minimum followup duration of 58 months, Phillips and colleagues reported no correlation between closure of the fenestration and preservation of range of motion. Patients improved their flexion–extension arc of motion by 20 degrees, on average. No complications to the ulnar nerve were encountered.


In another 17 patients, the range of motion improved by 16 degrees in flexion and extension and by 35 degrees in forearm rotation, despite no formal radial fossa debridement. Of note, the Short Form-36 scores were better than for age- and sex-adjusted normal values.


Arthroscopic Joint Debridement


Technique


This technique is modified from Savoie and colleagues. Position the patient prone with care taken to pad any bony prominences. Place the arm in a holder or over a bump, with the forearm free and the elbow flexed at 90 degrees. Unlike for open debridement, address the anterior compartment first. Use an anterior proximal medial portal to enter the joint, and then use an anterior proximal lateral working portal. If any ulnar nerve symptoms are present or if the patient has very limited elbow flexion preoperatively, ulnar nerve release with or without transposition should be performed. In the anterior compartment, resect all loose bodies, chondral flaps, and impinging osteophytes. To aid in visualization, synovectomy should be performed and retractors can be used. Ensure that the coronoid fossa is open and confirm that bony resection is adequate to allow unimpeded elbow flexion. The radial head can be excised, if necessary, with a shaver introduced in the straight lateral portal. Keep in mind that the posterior interosseous nerve lies directly adjacent to the capsule anterior to the radial head along a fatty stripe at the edge of the brachialis muscle. Resection of 5 to 8 mm usually is sufficient but should be evaluated by taking the elbow through a range of motion with valgus stress to make sure that the remaining proximal radius does not contact the capitellum. Fluoroscopy can be helpful in determining the extent of resection. If the elbow becomes unstable after radial head resection, conversion to an open procedure with radial head replacement is necessary with or without medial ligament reconstruction. Once the bony work is done, the anterior capsule can be resected if a contracture is known or expected, although such resection rarely is necessary.


With the inflow left in the anterior proximal medial portal, enter the posterior compartment through the posterolateral portal. As for an open O-K procedure, use the transtricipital posterior central portal for instrumentation. Using a shaver, perform debridement of the olecranon fossa and the tip of the olecranon until at least full extension or even slight hyperextension can be achieved. Exercise great care when performing debridement of the medial gutter. Suction should be turned off, and the shaver should be facing away from the cubital tunnel. It is easy to unintentionally “debride” the ulnar nerve while performing synovectomy. Proceed to the lateral gutter and excise the posterolateral plica. Switch instrumentation to a 5-mm drill and connect the olecranon and coronoid fossae. By using a notchplasty blade, enlarge the drill hole to at least 1 cm in diameter until full flexion and extension are achieved. Do not extend the hole into the medial or lateral columns of the distal humerus. Some surgeons prefer using a trephine or a Cloward drill to fenestrate the distal humerus. If no bony impingement remains but full flexion is not possible, release the posterior capsule. Likewise, if full extension is not possible, switch to the anterior portal and perform anterior capsular release. If desired, place an anterior and a posterior drain through the portal sites.


Results


In patients younger than 50 years, short-term results have been encouraging. Krishnan and colleagues reported results achieved in 11 patients who underwent arthroscopic ulnohumeral arthroplasty, along with ulnar nerve decompression in one and radial head excision in another. The mean flexion improved from 100 to 140 degrees, and extension improved from 40 to 7 degrees. Based on the Mayo Elbow Performance Score, 10 patients achieved excellent results and 1 achieved a good result. No patient experienced recurrence of olecranon fossa ossification or progression of arthritis within the 2-year followup period. Pain also improved, from a mean score of 9.2 (on a visual analog scale of 0 to 10 ) to a mean score of 1.7. Both professional athletes in the cohort were able to return to previous levels of competition.


The results were similar for 24 patients who were treated with a comparable technique at a mean age of 59 years. Range of motion improved from a range of 40 to 90 degrees to a range of 8 to 139 degrees. Combining objective and subjective criteria, 20 patients achieved excellent results, 2 good results, and 2 fair results. All patients, however, did experience improvement, and only one minor complication occurred.


Because of improved access to the radiocapitellar joint from the arthroscopic versus the open ulnohumeral arthroplasty, radial head excision and radiocapitellar debridement are possible. Kelly and colleagues treated 25 elbows that had Grade III and IV radiocapitellar arthritis with osteophyte debridement alone, without resecting the radial head. At a minimum of 24 months’ followup (average followup duration, 67 months), 24 patients felt “better” or “much better.” Only one patient reported no improvement, and no patient felt worse.


Cohen and colleagues compared the results of open and arthroscopic ulnohumeral arthroplasty. Patients were allocated to each intervention depending on the hospital of presentation. The populations were relatively comparable in terms of cause of condition, patient age, and severity of disease. No major complications occurred in either group, but patients who underwent an open technique had greater improvement in range of motion, whereas those who underwent an arthroscopic technique had greater improvement in pain relief. Patient satisfaction was equivalent. It might be that an open release does afford better visualization and therefore more accurate osteophyte resection but at the cost of increased soft tissue trauma and resultant pain.


Postoperative Protocols


Postoperatively, perform a neurologic examination to ensure posterior interosseous and ulnar nerve function. An indwelling interscalene or supraclavicular catheter can then be used as a continuous or intermittent block to limit postoperative pain and facilitate range-of-motion exercises, if warranted, particularly if a continuous passive motion (CPM) device is to be used. Depending on the patient, an overnight stay usually is sufficient.


Many protocols exist, varying from immediate range of motion in a CPM machine to splinting and delaying motion for 7 to 10 days. None of the protocols has a clear advantage, and it is up to the clinicians to determine the best protocols for the patients and situations.


Immediate range of motion with a CPM might yield better earlier motion gains but can cause pain, can cause tension on the wound, and can affect ulnar nerve function. The machine is costly, cumbersome, and perhaps best suited for a supervised setting in most environments. However, if rehabilitation services are limited, either in or out of the hospital, a CPM device might be ideal for patient-directed therapy without the need for intensive physical therapist oversight. Good results have been achieved with a CPM protocol after elbow debridement procedures; therefore, a CPM protocol remains a valid option.


If a CPM device is used, begin motion as early as immediately postoperatively or delay use if wound healing, joint stability, or ulnar nerve function is in question. The patient can continue CPM usage at home for up to 3 weeks after surgery. Alternatively, the patient can begin active and active-assisted motion under the supervision of a therapist in lieu of or in addition to use of the CPM. Supervised therapy should be continued on an outpatient basis 2 to 3 days a week for a minimum of 6 to 12 weeks or longer if needed. A patient-directed home program also should be instituted. If progress is slow, transition the program to passive motion with a therapist. Progressive static splinting is another option, either for routine use or for difficult cases.

Only gold members can continue reading. Log In or Register to continue

Stay updated, free articles. Join our Telegram channel

Jan 26, 2019 | Posted by in ORTHOPEDIC | Comments Off on Ulnohumeral Arthroplasty

Full access? Get Clinical Tree

Get Clinical Tree app for offline access