Chapter 40 Open Debridement and Interposition

Introduction

Open debridement of the elbow remains the mainstay of treatment for moderate to severe arthritis. However this statement fails to recognize the difficulties the surgeon faces when formulating a treatment plan for patients with ‘arthritis’ of the elbow. There are many causes, many operations with many failures in patients who have many expectations.

The many causes

Degenerative conditions of the elbow have a broad spectrum of pathology: primary osteoarthritis, inflammatory arthropathies, posttraumatic arthritis, osteochondritis dissecans and degenerative changes from instability. Furthermore conditions such as rheumatoid arthritis have their own spectrum of pathology – those who mainly present with deranged mechanics and those patients whose primary complaint is pain.¹ Published results rarely discriminate between these causes, so there is limited evidence as to which are best treated with open debridement. Moreover, knowing the aetiology of the arthropathy does not predict the exact cause of the pain and stiffness. Degenerative changes of the bone or soft tissues affect any part of the complex elbow joint, so it is better to determine the anatomical cause of the patient’s pain and stiffness. Only then can it can be accurately addressed at the time of surgery.

Many operations

Fusion, resection arthroplasty, interposition arthroplasty, open or arthroscopic debridement and total joint replacement all have a role to play in the surgical treatment of elbow arthritis. Open debridement alone describes several similar operations with their own modifications and all claim to successfully treat elbow arthritis. Outerbridge–Kashiwagi procedure, ulnohumeral arthroplasty, the column procedure and Tsuge extensive debridement arthroplasty can be performed. All these operations incorporate several techniques: removal of osteophytes, removal of loose bodies, release of capsule, with or without management of the ulnar nerve and radial head excision. One operation does not fit all, however, each described procedure does add to our arsenal of techniques which can be deployed in any given situation. Once the anatomical cause of the elbow pain and stiffness is elicited, it is better to employ a tailor-made approach and technique than a named operation.

Many failures

The elbow is a very complex joint. It has three articulations, any one of which can undergo degenerate changes or develop osteophytes and impingement. It has a considerable soft tissue envelope, which is also particularly prone to injury and contracture. In addition, all three major nerves of the arm pass intimately to the joint, rendering them susceptible to injury, either as a result of the disease process or at the time of surgery. Despite its range of movement, the elbow has a high bony congruency, as the olecranon and coronoid engage respectively into their fossae on the humerus. The joint is therefore susceptible to degenerative changes in the presence of only minor changes in the kinematics of the articulation. In addition, postoperatively the elbow requires early mobilization as a result of its propensity to stiffness after injury. This surgery is technically demanding and associated with a relatively high complication rate, with some studies reporting poor outcomes after open debridement of the elbow. In our own series of 59 patients, 10% reported being worse after the surgery. Conservative measures therefore must always be exhausted.

Clinical Pearl 40.1

Elbow arthritis typically affects young manual workers who have high demands on their joints. It is these same patients who are least able to modify their activity levels. Patient selection is vital.

Summary Box 40.1

• Identify the anatomical causes of the pain and stiffness as well as the pathological process which led to them.

• Direct surgery towards those anatomical causes rather than performing a named operation.

• Exhaust conservative measures prior to surgery, as results can be poor.

Background/aetiology

Historically the treatment for painful elbow ankylosis was a resection arthroplasty; resection of the painful joint was achieved by excising the entire olecranon, radial head and distal humerus above the condyles (Fig. 40.1A). Whilst in most cases this gave good pain relief, instability was common as there were no soft tissue or bony stabilizers remaining after surgery. Stability relied purely on the fibrous scar tissue between the cut bone surfaces. Despite this, good results were reported in posttraumatic, tuberculosis and rheumatoid arthrirtis.²^–⁴ Defontaine introduced the interposition as a refinement to the resection arthroplasty in 1887.⁵ By removing less bone and leaving a fulcrum between the olecranon and the distal humerus, he addressed the difficulty of instability experienced in resection arthroplasty (Fig. 40.1B). Tissue was positioned in the joint to act as a spacer, keeping the collateral ligaments functional and providing a pain-free articulation. The material used was varied and included muscle transposition, skin, fat or even pig’s bladder. Despite the use of an interposition graft, however, because less bone was excised, stiffness and even reankylosis could still be a problem. Hass cut the distal humerus into a wedge with the idea of reducing bone contact while still providing a fulcrum, however, pain, stiffness and wear of the articulation remained a persistent problem.⁶ Schüller first published the use of interposition in rheumatoid elbows in 1893. Hurri et al reported on 76 rheumatoid elbows and found that interposition arthroplasty provided better stability compared with the group of patients who had had a resection arthroplasty alone.³ However, their results also showed that only 40% were pain-free compared with 64% in the resection group. These were also the findings of Buzby, who concluded that patients were happier with a pain-free, flail elbow than they were with the more stable but painful interposition arthroplasty, the surgery often providing only a few degrees of extra motion.² Even in these early reports it became clear that movement was always achieved at the expense of stability, while movement with stability resulted in less predictable pain relief (Fig. 40.2).⁴

Figure 40.1 Resection arthroplasty of the elbow. (A) Extraperiosteal resection arthroplasty had high rates of instability. (B) The extent of the resection arthroplasty with the facial interposition. The ‘V’ cut maintains a fulcrum and is resurfaced with facia.

Figure 40.2 Relationship of range of motion, pain and instability during surgical release and debridement. As the range of motion is increased the elbow is subject to increasing instability (A). Gaining movement while maintaining stability can result in continuing pain (B).

In 1971, Peterson and Janes published the experience from the Mayo clinic, which identified a spectrum of pathology in the rheumatoid elbow; those with deranged mechanics and those patients whose primary complaint was pain.¹ In patients whose primary complaint was pain, a limited open debridement, synovectomy with radial head excision produced better results than interposition. The use of interposition arthroplasty has declined with the increasing success of total elbow arthroplasty, which gives better pain-free range of motion and stability in the low-demand patient.

It was not until the 1970s that Minami ⁷ and Kashiwagi⁸ published the first papers giving a detailed description and recommended treatment option for less severe elbow osteoarthritis. A procedure first described by Outerbridge and then published by Kashiwagi became known as the Outerbridge–Kashiwagi procedure. In 1992 this was modified by Morrey, who used a trephine to remove osteophytes encroaching on the olecranon and coronoid fossae, with elevation rather than splitting of the triceps, the so-called ulnohumeral arthroplasty.⁹ The column procedure approached the elbow via a lateral incision, debriding osteophytes and releasing the capsule through both anterior and posterior intervals. A more extensive debridement arthroplasty was described by Tsuge and Mizusek, which involved a formal disarticulation of the joint, with or without release of the collateral ligaments, excision of the capsule and reshaping of the radial head.¹⁰

As each refinement in surgical technique has evolved, so has our understanding of their limitations and the patients they will benefit. Each development has removed patients from the list that previously would have received a fusion or resection arthroplasty, leaving only a few for whom there is no alternative. Less invasive techniques with more predictable results now benefit patients who traditionally would not have been offered surgery at all. This chapter looks at open debridement and interposition arthroplasty and identifies those patients who will benefit from them. The preferred technique, with tips and tricks, is illustrated and the published results are reviewed.

Aetiology of pain stiffness around the elbow

Primary osteoarthritis

This accounts for only 2–3% of patients presenting with elbow arthritis.¹¹ It seems to almost exclusively affect men who are engaged in repetitive heavy manual labour and is presumably as a result of a genetic predisposition, followed by environmental stimulus for wear. The pathological changes which occur as the disease process progresses have been described.^12,¹³ The elbow forms osteophytes which occur on the coronoid, olecranon and fill their respective fossae on the humerus. Due to the high congruency of the joint, there is an early decrease in the range of movement. Pain can occur where the extra bone growth impinges on neighbouring normal bone or due to the development of a ‘kissing lesion’. The joint space, however, is initially maintained and the ulnohumeral articular cartilage is not worn.^10,^14,¹⁵ It is this characteristic which allows for the successful treatment with debridement of the extrinsic bone and soft tissue, leaving the relatively preserved ulnohumeral articulation alone. Osteophytes can break off and form loose bodies which cause locking as they interpose themselves within the joint. The ulnar nerve can also be irritated by the degenerative processes within the elbow and can often be a leading source of pain. Finally, ulnohumeral articular wear develops; this tends to cause pain which persists throughout the entire range of motion. Removal of osteophytes and soft tissue release will be less successful in these patients, as the ulnohumeral joint has intrinsic wear.

Posttraumatic osteoarthritis

This can be as a result of malunion after fracture of the articular surface, leading to incongruence and wear, or may be due to an osteochondral injury, which can also result in early degenerative changes. If there is significant intrinsic wear to the intra-articular cartilage of the ulnohumeral joint, open debridement may not be successful. Trauma can also lead to injury or attenuation of the medial collateral ligaments of the elbow. With time the resulting valgus laxity will cause posteromedial impingement with osteophyte formation on the posteromedial olecranon and humerus. This wear pattern will have identical radiological appearances to primary osteoarthritis and can be managed in a similar way with open debridement. In our experience, lorry drivers who repeatedly exert a valgus strain when tying down their load, and some athletes, such as boxers, weightlifters and throwers, can develop this pattern of osteoarthritis.

Heterotopic ossification

This is new bone formation within non-osseous tissues typically after elbow dislocation, with an incidence varying from 25% to 75%.^12,¹⁶ This high incidence is thought to be as a result of brachialis, which is mainly muscular as it crosses the joint, being torn at the time of dislocation. It also occurs after surgery and its incidence is increased in the presence of a concomitant head injury.

Inflammatory arthritis

This is a less common indication for open debridement. The soft tissues are not prone to contracture and osteophytes are not a common feature of the arthropathy. The wear pattern is more intra-articular in nature and therefore less suitable for joint preserving debridement surgery. Only 5% of rheumatoid patients have isolated elbow arthritis.

Clinical Pearl 40.2

Open debridement is a joint preserving operation and is contraindicated in the presence of significant ulnohumeral articular cartilage wear.

Presentation, investigation and treatment options

The decision to operate and which procedure to perform is reached following a careful history, examination and investigations. Some specific questions should be answered to help in the decision-making process.

History

The patient’s age and occupation is important. Find out why the patient has consented to treatment. While most patients will complain of both pain and loss of movement, one is often more of a problem than the other. Is the loss to range of movement functionally significant? Does it stop them doing their job? If so, document whether it is flexion or extension which is the main limiting factor. This will guide you into which soft tissues or bone needs to be debrided to give the elbow a functional range of movement (Fig. 40.3). Can the patient reduce the demands on the elbow or even change jobs?

Figure 40.3 The anatomy which blocks flexion/extension. (A) Bone and soft tissue which block flexion. (B) Bone and soft tissue which block extension. (C) Lateral margins of osteophytes.

Are there symptoms of locking, clicking or instability? Locking and clicking suggest loose bodies which can be easily removed without the need to proceed to a more extensive debridement. Has the patient got any distal neurological symptoms, such as sensory disturbance or muscle weakness? In this case the ulnar nerve will need to be addressed. Even in the presence of marked radiographic degenerative changes, when neurological symptoms are the main complaint, ulnar nerve release alone can adequately relieve symptoms.

If trauma is involved, the exact mechanism, the fracture pattern, and orientation and management is useful information. If it is an inflammatory arthropathy, other joints which are affected must be noted, as they can have an impact on the function of the elbow, along with the medications and current status of the disease process. Aetiology of the arthritis will give important information as to the condition of the bone and soft tissues prior to surgery. I specifically enquire about any history of previous infection.

It is also important to ascertain patient expectations. They must be realistic as the elbow is not going to be returned to normal. The literature suggests an increase in the arc of motion of between 22° and 35° can be expected and is dependent on patient compliance with postoperative physiotherapy. They must be made aware that pain relief after open debridement can be modest and the range of motion will deteriorate with time. If there is any doubt as to their commitment to the process then surgery should not be offered.

Summary Box 40.2

• Discuss ways in which the patient might manage at home or work without having an operation.

• Really get to the bottom of what is causing the main problem. Even in the presence of gross radiological degenerative changes, can you get away with reducing the level of pain with less radical surgery? That is, management of loose bodies, ulnar nerve or radial head alone.

• Realistic patient expectations and commitment to the rehabilitation are vital.

Clinical examination

There are several specific points that must be looked at in the examination prior to surgery. On inspection look for previous surgical incisions and the quality of the skin, consider whether your surgery can be approached through the old scar.

Is pain limited to the endpoint of movement, suggesting impingement due to osteophytes which can be removed? Or, is it throughout the arc of movement, suggesting intra-articular wear, which is less likely to benefit from joint preserving open debridement (Fig. 40.4). Does the endpoint have a solid, bony block to it, or is it soft and springy, which would suggest a soft tissue contracture.

Figure 40.4 (A,B) Radiographic appearances of intrinsic wear.

Investigation

Anteroposterior and lateral radiographs will help locate the osteophytes that need to be removed. Evidence of joint space narrowing will suggest excessive articular wear. Adequacy and the quality of the bone are evaluated. Loose bodies can often be seen along with calcification of the ulnar collateral ligament, the latter can be associated with ulnar nerve symptoms. The role of computed tomography (CT) has not been established, but is certainly helpful for identifying the position and extent of heterotopic ossification and loose bodies. I find a three-dimensional CT helpful in planning surgery. Magnetic resonance imaging can be used to evaluate ligament anatomy and stability. Finally, nerve conduction studies and electromyographic (EMG) sampling can be useful to exclude radiculopathy or pain of neurological origin.

Ultimately the decision to perform debridement is based on the disease process, anatomical culprit of the pain and stiffness, patient and surgeon factors. Table 40.1 summarizes the factors which the surgeon should consider in the management of elbow arthritis.

Table 40.1 Factors to consider prior to surgery

Patient factors	Age
	Activity level
	Willingness to modify activity level
	Poor rehabilitation potential
Anatomical factors	Articular wear
	Impingement spurs
	Loose bodies
	Ulna nerve symptoms
	Soft tissue contracture
	Stability
Disease factors	Primary osteoarthritis
	Inflammatory arthritis
	Trauma
	OCD in young patient
	Athletes
Surgeon factors	Training
	Experience
	Technical expertise

Treatment options

Next we must consider the approach and extent of the surgery which will be required to achieve the goals identified. There is now an accepted treatment algorithm for the management of elbow arthropathy which starts with simple measures such as analgesia together with modification of daily activities. Unfortunately, the patient group that typically experiences the degenerative changes is that of middle-aged manual workers who are usually the least able to modify their occupation. If non-steroidal antiinflammatory analgesia is insufficient to control the symptoms then intra-articular steroid injection can be helpful in reducing pain and swelling. As with all joints, however, the benefits are often short term and subsequent injections provide diminishing relief of symptoms. Physiotherapy can help maintain range of motion and occupational therapy can provide splints for pain relief or devices to help modify activities of daily living.

While total joint replacement has been adopted as the treatment of choice in most other joints of the body, the role of total elbow replacement in degenerative conditions at the elbow remains limited. Kozak reported complications in four out of five elbow replacements for primary osteoarthritis at 3 years.¹⁸ In addition, elbow arthritis again largely affects middle-aged men in manual work who wish to maintain their high demands on the elbow joint; they are obviously not good candidates for arthroplasty.⁹

Surgical debridement serves to remove painful osteophytes which impinge causing pain and loss of movement, along with a release of soft tissues to improve movement. This is only effective in patients with relatively well-preserved ulnohumeral cartilage. If there is excessive wear and joint-space narrowing the elbow will continue to be painful and total elbow arthroplasty or interposition arthroplasty would be the better option. Various techniques to debride the elbow can now be undertaken arthroscopically. Recent advances in arthroscopic surgery to the elbow have meant many patients with less severe arthritis can be treated in this way. However, it is contraindicated in the presence of extensive osteophytes, multiple pathology, previous surgery and uncertain anatomy. While there may have been some excellent reported outcomes, arthroscopic debridement is regarded by many surgeons as having an increased risk of complications,¹⁹^–²³ with no clear clinical benefit over open surgery.^24,²⁵ Open debridement of the elbow remains the mainstay of treatment for moderate to severe elbow arthritis.

No consensus exists among orthopaedic surgeons as to the most effective method of an open debridement and on which patients they should be performed. One operation does not fit all; each described procedure provides us with techniques which can be deployed on a patient-to-patient basis. The techniques are illustrated later in this chapter.

The column procedure is best suited to treat soft tissue contractures without bony impingement. It can be performed either through a medial or lateral incision. It makes sense to use the medial approach when the ulnar nerve needs to be decompressed; it also allows the surgeon to address any osteophytes in the medial gutter, while protecting the nerve and the anterior oblique bundle of the medial collateral ligament. The disadvantage is the limited access to the olecranon fossa and as a consequence sometimes inadequate removal of bone.

The Outerbridge–Kashiwagi (OK) procedure gives excellent exposure to the central posterior osteophytes and is therefore best suited to patients with bony impingement. It has the advantage of giving access to both the front and back of the joint through a posterior incision, without excessive soft tissue disruption. This is achieved by making a window through the olecranon fossa and reaching through this fenestration into the anterior joint. Reducing surgical soft tissue trauma in this way means there is less swelling which is important as bleeding and swelling after surgery turns into scar tissue which ultimately results in stiffness. Good results depend on early postoperative mobilization.

The Morrey ulnohumeral arthroplasty (UHA) is a modification of the OK procedure, which does not involve splitting the triceps, but includes performing a clean-cut trephine through the olecranon fossa. This has the benefit of less postoperative pain with less bone dust seeding into the muscle. Both the OK and UHA techniques are, however, limited by the failure to address any radial head pathology; furthermore adequate release of the anterior capsule is difficult to perform safely through the 15 mm window. By extending the incision and dissecting medial or laterally, the anterior capsule can be approached around the side, thus combining the UHA and column procedures.

An extensile debridement can be performed when more extensive hypertrophic changes are present. The joint is disarticulated by releasing the lateral collateral ligament complex and the common extensor origin, similar to the technique that can be used in total elbow arthroplasty. This gives the very best exposure through 360°, including the radial head, but at the expense of considerable soft tissue dissection. There have been no reports of postoperative instability in patients who have had their collateral ligaments detached in this way.

Contraindications for open debridement

The most frequent contraindication is in patients with poor rehabilitation potential. Some patients are easily identified, such as those with a history of drug and alcohol abuse. These patients are rarely compliant and, even after counselling, they rarely engage fully in their postoperative rehabilitation protocols and have a poor outcome as a result. Most others will comply to a varying degree; however, it must be made absolutely clear before surgery that rehabilitation will be painful and arduous. In addition spasticity or brain injury with limited voluntary control is a relative contraindication for surgical release; however, it may be required for hygiene purposes. Poor soft tissue coverage can make postoperative splintage hazardous, as wound breakdown will slow rehabilitation, and recurrent soft tissue contracture is sure to follow.

Patients with minimal osteophyte formation, ulnohumeral joint space narrowing on X-ray and pain throughout the full range of movement, have symptoms from ulnohumeral cartilage wear. Patients with this intrinsic wear pattern will not benefit from a joint-preserving operation and will be better served with an interposition arthroplasty.

The presence of metabolically active heterotopic ossification is a relative contraindication to early open debridement. The optimal timing for excision of the heterotopic ossification has not been established. A normal alkaline phosphatase is useful in patients who have large amounts of heterotopic ossification, typically around the hip. However, a relatively small amount of heterotopic ossification around the elbow results in only a small rise in alkaline phosphatase levels, which makes it an unreliable indicator of osteoblast activity. A three-phase technetium scan has been reported as being 90% sensitive for metabolically active heterotopic ossification and is therefore the preferred method.²⁶ Heterotopic ossification can absorb over time, especially in children who have a recovering head injury. There is some evidence that earlier release is preferable (6 months) as it gives better long-term results.²⁷^–²⁹ The use of preoperative radiotherapy and non-steroidal antiinflammatory drugs also decreases the risk of recurrence after excision.²⁹

Interposition arthroplasty is an option if the ulnohumeral joint has intra-articular wear and the patient is too young or active for a total elbow replacement. Interposition arthroplasty does not carry the same weight-lifting restriction as total elbow arthroplasty (5 kg lifting or 2 kg repetitive restriction) and has been shown to be durable in the active patient.^30,³¹ Alternatives are limited in these patients; arthrodesis severely limits the functional tasks that can be performed and is poorly tolerated. Resection arthroplasty creates severe disabling instability in most patients and is only indicated in those with active infection. Satisfactory results have been published for interposition arthroplasty in healthy, active patients with severe posttraumatic or rheumatoid elbow arthrosis.^30,³²^–³⁵

This salvage procedure, however, should only be considered when the patient is disabled by pain with loss of function and non-operative measures have been exhausted.³⁵ There is no age limit as a guide, but interposition arthroplasty is typically performed in patients with severe inflammatory arthritis (<30 years old) or posttraumatic arthritis (<60 years old). It is important that the elbow is stable as there is a significant association between poor outcomes and preoperative instability.^30,³⁵ For the interposition arthroplasty to have the best results there needs to be both bony congruence and soft tissue stability. The most common contraindication is insufficient bone stock which will increase postoperative instability due to lack of congruency. This can be restored by grafting the distal humerus as a staged procedure. An alternative is to use the calcaneal bone graft attached to the Achilles tendon at the time of surgery. Deformity which alters the mechanical axis of the arm will need to be corrected with an osteotomy if possible, as the pull of the flexors and extensors must be centred over the arthroplasty for stability. Ten degrees of varus or valgus is considered to be the limit. The interposition arthroplasty will not, however, provide prolonged pain-free stability if the patient is involved in very heavy manual labour which requires lifting with abduction of the shoulder. In these patients either a new occupation must be found or rarely an arthrodesis may be a better option. The sustained use of crutches or having to transfer from bed to a chair is also a relative contraindication.

As with any joint reconstruction there has to be active movement across the articulation; in this case the absence of the elbow flexors is an absolute contraindication. The use of dead interposition graft material means any active infection must be eradicated, typically free of infection for 6 months after the cessation of antibiotics. Preoperative assessment alone is not a sufficient indication to proceed to interposition; the articular cartilage must be assessed at the time of surgery after dislocation of the joint. It is important not to confuse the areas of thin or absent cartilage in the mid portion of the olecranon as being arthritic in origin. If there is insufficient wear to warrant interposition then an extensile debridement alone should be performed.

The principle of the surgery is to place scar tissue between the distal humerus and olecranon in place of the articular cartilage. In 1990 Morrey developed three additional features to the technique: distraction using an external fixator, early postoperative motion and a larger interposition graft.³⁶ Various interposition materials have been used in the ulnohumeral joint, including fascia lata,³⁵ cutis graft,³⁷ Achilles tendon allograft,³⁰ Gelfoam³⁸ and silicone.³⁹ The Wrightington experience has been with Achilles tendon allograft, which has the benefit of no donor site morbidity and an adequate thickness without having to suture several layers together. There is some evidence that it may survive longer than fascial interposition graft, leading to fewer patients requiring revision surgery in the early postoperative period.³⁰ The elbow is then held with a dynamic external fixator which is used as a means of initiating early motion while neutralizing forces and thus protecting the soft tissues, the interposed graft, and any ligament repair or reconstruction.^31,³⁶