Recent technologic advances in elbow arthroscopy have expanded its indications for the management of elbow joint stiffness. One of these expanded indications is the treatment of elbow joint contracture from a variety of causes, including posttraumatic, congenital, and atraumatic. Most intra-articular and some extra-articular elbow stiffness may be successfully treated with arthroscopy. With the recent emphasis on minimally invasive surgery, treating elbow joint stiffness arthroscopically has become increasingly viable. This article focuses on management of intra-articular causes of elbow stiffness and reviews the indications, techniques, and results for arthroscopic management of elbow contracture.
INDICATIONS AND CONTRAINDICATIONS
The primary indication for arthroscopic release of the stiff elbow is a painful contracture of 30° or more that is functionally limiting and refractory to conservative treatment. The American Academy of Orthopaedic Surgeons defines normal motion of the elbow joint from 0° to 146° flexion (1). In 1981 Morrey et al. (2) demonstrated that 90% of all daily activities could be achieved with a functional arc of motion from 30° to 130° flexion. However, of the functions reported in this study, none include sporting or work-related activities. Daily activities such as shoelace tying and certain occupations may require more than 30° of elbow extension. Therefore, the indications for surgery depend on the patient's functional needs. The indications may be loss of 30° of elbow extension, painful terminal extension of less than 30°, or elbow contractures of less than 30° that impair occupational functional demands. Patients with a lesser degree of flexion contracture who have painful popping or locking secondary to intra-articular stiffness may also be candidates for concomitant arthroscopic release at the time of surgery.
Relative contraindications to arthroscopic management of the stiff elbow include altered neurovascular anatomy, such as a subluxating ulnar nerve or previous ulnar nerve transposition, and certain extra-articular deformities that might entrap neurovascular structures. Limited experience with elbow arthroscopy is also a relative contraindication owing to the technical difficulty of the procedure. Because the capsular volume of the elbow joint is diminished and less compliant, adequate joint distention before portal placement may not be obtained in the arthrofibrotic elbow. This increases the risk for neurovascular injury during portal placement.
Preoperative evaluation begins with a thorough history and physical examination. It is important to delineate the exact nature of the cause of the contracture, because primary osteoarthritis involving predominantly the ulnohumeral joint necessitates a different surgical technique than does elbow stiffness after a radial head fracture. It is also important to determine whether the limitation of motion is painful, because most people with a 30° extension loss can perform activities of daily living well (2). During the physical examination, ulnar nerve subluxation must be identified if elbow arthroscopy is contemplated. Standard radiographs are usually all that are required for preoperative planning, although lateral tomograms may be helpful to identify unusual deformity of the olecranon and coronoid fossae.
Magnetic resonance imaging (MRI), computed tomography, and arthrography are rarely indicated and usually do not contribute significant information for surgical treatment. However, in a recent study by Fortier et al. (3), MRI was used to assess posttraumatic flexion contracture of the elbow before surgery in 12 patients. In comparing MRI with plain films, tomograms, and computed tomography scans, they determined that MRI allowed better identification of loose bodies and soft tissue abnormalities including capsular and collateral ligament thickening. Therefore, MRI may be useful in certain cases but generally is not required in the preoperative evaluation of posttraumatic elbow flexion contracture.
In treating the stiff elbow, the specific cause of stiffness must be identified for successful results. Patients with skin contractures secondary to burns or muscle spasticity, as in cerebral palsy, obviously require different treatment protocols from those for patients with posttraumatic or osteoarthritic causes. Intra-articular causes of elbow contracture are most amenable to arthroscopic techniques. Some extrinsic causes, including collateral ligament contracture and extensor musculature problems, may be adequately treated arthroscopically as well. Flexion contracture secondary to muscle spasticity, head injury, skin contractures, or heterotopic ossification may well require an open surgical procedure for adequate release.
The ultimate goal of treatment is to achieve a pain-free elbow with a functional range of motion and normal stability. Nonoperative treatments include physical therapy and static and dynamic splinting and should be considered for up to 1 year after the onset of the contracture. In general, the more recent the onset of the elbow contracture, the more favorably it responds to nonsurgical management. It is important to ascertain during physical examination whether there is a firm endpoint to range of motion, because these contractures are less likely to respond to a nonsurgical treatment. Goals of nonoperative treatment are to regain elbow motion gradually without creating more inflammation, capsular tearing, and hemorrhage. If therapy results in increased inflammation, the arthrofibrotic process is repeated and the inflammation persists, resulting in recalcitrant elbow stiffness. The generous use of ice, anti-inflammatory medications, and non-narcotic analgesics are helpful during the splinting process. Physical therapy should be active-assisted with no passive stretching, because this may result in repetitive injury to the elbow joint capsule. The elbow joint should not be manipulated owing to the risk of periarticular fractures and heterotopic ossification. The most important factor to successful nonoperative treatment is the appropriate use of splinting.
Instrumentation and Setup
The equipment necessary for the procedure includes a 4.5-or 5-mm 30° arthroscope with a wide-angle lens, a 4.5-mm synovectomy blade, and standard video recording equipment. At our institution we perform elbow arthroscopy with gravity inflow, because pumps may exceed the pressure capacity of the elbow joint capsule, resulting in rupture and fluid extravasation.
The patient is placed under general endotracheal anesthesia and a tourniquet is placed proximally on the affected extremity. The patient is then positioned prone with adequate chest support. The extremity is supported on a 4-inch block and placed on a standard arm board parallel to the operating room table that allows adequate mobility of the elbow joint during the arthroscopic procedure (Fig. 1). The tourniquet is inflated to 250 or 300 mm Hg. The arm is then prepped and draped in the sterile fashion and a Coban wrap is placed distally on the hand and wrapped proximally. This wrap decreases the space available for fluid extravasation during the procedure and increases the space available for extravasated fluid after the procedure. Motion of the elbow is then tested with the forearm placed in pronation, neutral rotation, and supination.
Diagnostic Elbow Arthroscopy.
Before any portal placement, the anatomy of the elbow joint is diagrammed with a marking pen. The medial and lateral epicondyles are marked as well as the proximal olecranon. The ulnar nerve is then palpated and drawn out as it courses through its groove. The proximal medial portal is marked approximately 2 cm anterior and 2 cm proximal to the medial epicondyle and is placed anterior to the medial intermuscular septum (Fig. 2). The joint is then insufflated from the region of the posterocentral portal and a spinal needle introduced where the proximal medial portal is to be placed. The spinal needle is then removed and a small skin incision is made through the skin only, taking care to pull the skin against the scalpel blade during the incision. A blunt trocar is used to palpate the intermuscular septum and is directed just anterior to it and the distal humerus. The joint is then entered using the blunt trocar. The arthroscope is introduced through the proximal medial cannula and a diagnostic arthroscopy of the anterior compartment is performed.
A proximal lateral portal is established, preferably using the outside-in technique with a spinal needle. However, in some cases, an inside-out technique with a Wissinger rod may be required. The portal should be positioned just superior to the capitellum to ensure the safety of the posterior interosseous nerve. Usually, this portal is located approximately 2 cm anterior and 2 cm proximal to the lateral epicondyle. The cannula is then inserted and the shaver introduced. The proximal lateral portal serves as a working portal to release the intra-articular scar tissue from the radial head and coronoid process. Debridement of fibrotic tissue within the radiocapitellar joint is then performed with the forearm in pronation and supination to ensure adequate release. Care is taken at this point not to direct the shaver blade toward the anterolateral capsule just distal to the radiocapitellar joint, because this is where the posterior interosseous nerve is located. Debridement of the coronoid process may be accomplished from this position as well if necessary.
Anterior Capsular Release.
After adequate debridement and definition of the anterior intra-articular stiffness, an anterior capsulectomy is initiated. For this portion of the procedure the arthroscope is maintained in the proximal medial portal and the shaver introduced through the proximal lateral portal. The capsule is then released from the anterior humerus, beginning at the coronoid fossa and continuing laterally until complete release of the capsule from the lateral side has been accomplished. Approximately 1 to 2 cm of proximal capsule should be completely excised during this process to prevent reformation of capsular scar tissue in the area. The arthroscope is then changed to the proximal lateral portal and the shaver is introduced in the proximal medial portal and the capsular excision is continued from the medial side (Fig. 3). The medial release continues until the medial intermuscular septum is reached (Fig. 4). Any release medial to this point will result in injury to the ulnar nerve. During this process the proximal portion of the capsule is excised until brachialis fibers are identified from lateral to medial. Capsular release is continued until a posterior block to extension is identified, until the muscle fibers are completely visible from medial to lateral, or until the capsular structures are no longer taut (Fig. 5). To minimize risk of neurovascular injury, the shaver blade must be maintained on the anterior aspect of the distal humerus at all times.
Once a complete anterior capsular release has been performed and maximum extension achieved, inflow is maintained through the cannula in the proximal medial portal and the posterocentral and posterolateral portals are created. The posterocentral portal is placed directly posterior to the olecranon fossa, approximately 2 cm proximal to the olecranon process. The posterolateral portal is placed 2 cm lateral to the posterocentral portal, entering adjacent to the lateral edge of the triceps. The arthroscope is then introduced into the posterolateral portal and the shaver into the posterocentral portal and a general debridement is performed. A notchplasty blade may then be used to resect any spurring on the olecranon process as well as to deepen the olecranon fossa (Fig. 6). The olecranon and humerus must be adequately debrided of all osteophytes in order to successfully regain terminal extension. Olecranon process excision is continued until the posterior impingement is eliminated and adequate extension regained (Fig. 7). To increase elbow flexion, the posterosuperior portion of the elbow joint must be debrided. Removal of any adhesions between the triceps tendon and the posterior humerus should help to increase flexion of the elbow.
Debridement of the Posteromedial and Posterolateral Gutters.
The final portion of the release is the debridement of the posteromedial and posterolateral gutters of any adhesions. For debridement of the posterolateral gutter, the arthroscope is placed posterocentrally and the shaver is placed posterolaterally. Excision of adhesions is then initiated proximally and a separate straight lateral soft spot portal may be necessary in order to adequately debride the posterior radiocapitellar joint, the posterior radioulnar joint, or posterolateral plica. The shaver is then changed to the posterocentral portal and the arthroscope is maintained in the posterolateral portal for debridement of the posteromedial gutter. This process is continued from proximal to distal, taking care to keep the shaver blade facing toward the ulnohumeral articulation and away from the ulnar nerve.
In cases of large osteophytic buildup of the olecranon fossa, it may be necessary to perform an ulnohumeral arthroplasty to regain terminal extension. This is accomplished with the arthroscope in the posterolateral portal and a 5-mm drill bit introduced into the posterocentral portal and centered in the olecranon fossa. In the normal elbow, the olecranon fossa is quite thin, often only 1 to 2 mm in thickness. However, frequently in the arthritic elbow it is thickened, which is important to realize during drilling. Inflow is maintained through the 5-mm proximal medial cannula. The tip of the proximal medial cannula serves as a guide during drilling from the posterocentral portal. Two to three drill holes adjacent to one another may be required to initiate the ulnohumeral arthroplasty. Next, a burr is introduced and circumferential widening of the drill holes is initiated. Care should be taken during this portion of the procedure not to resect too much bone inferiorly or to excessively enlarge the hole, because this could lead to postoperative supracondylar fracture. Debridement is continued until the edges are smooth and the hole is approximately 15 mm wide (Fig. 8). Under arthroscopic visualization, the elbow is then taken through a range of flexion and extension to ensure that there is adequate room for the olecranon process to enter into the enlarged fossa.
Arthroscopic Radial Head Excision.
In patients with posttraumatic arthrofibrosis after a radial head fracture, it is frequently necessary to perform arthroscopic radial head excision concomitant with capsular release. It is also occasionally necessary in patients with primary osteoarthritis of the elbow joint (Fig. 9). Indications for radial head excision are arthritic involvement of the radiocapitellar joint and mechanical block to pronation and supination. The arthroscope is introduced from the proximal medial portal and the shaver from the proximal lateral portal. Debridement anteriorly is then performed to allow adequate visualization of the radiocapitellar joint as well as the ulnohumeral joint. Once this has been accomplished, the shaver is introduced from the proximal lateral portal and the anterior and anterolateral aspects of the radial head are identified. Care is taken during this portion of the procedure to maintain the shaver blade away from the anterolateral capsule, with cautious use of suction to avoid injury to the posterior interosseous nerve. The anterolateral portion of the radial head is then partially resected from the superolateral portal and defined with a burr. Next, the spinal needle is introduced from posterior in the area of the straight lateral portal through the radiocapitellar articulation. A portal is then created and a cannula introduced through the radiocapitellar joint. Excision begins with resection of the posterior portion of the radial head using controlled, sweeping motions to ensure a smooth resection. This process is continued anteriorly until approximately 6 mm of radial head has been excised (Fig. 10). The remaining anterolateral portion of bone should be removed with a grasper or means other than the burr to avoid injury to the posterior interosseous nerve. Once 6 mm of bone has been resected, it must be determined whether the proximal radioulnar articulation is involved in the arthritic process. If there is a mechanical block to motion or if arthritis is present in this articulation, resection is continued for another 3 to 4 mm to ensure restoration of pronation and supination.
On completion of the procedure, drains may be inserted in the proximal medial portal and posterocentral portal. The lateral soft spot portal is generally sutured and all other portals are left open to drain. A pain pump is placed through the posterocentral portal into the elbow joint. Sterile dressings are then applied and a final determination of range of motion is made. The elbow is placed in full extension and supination and maintained in this position with the use of anterior and posterior splints.
Patients are maintained in full extension and supination until awake and alert. An aggressive active and passive physical therapy program is instituted immediately. Constant passive motion machines may be used to help increase early flexion and extension, but they probably provide little long-term benefit. The patient is maintained on an aggressive active and passive physical therapy program with the use of splinting at night and while not in therapy. Night splinting may be discontinued at 3 weeks if an adequate range of motion has already been achieved. Physical therapy is then continued once or twice daily until 6 weeks after surgery. Patients are allowed to return to light work as soon as they are pain free, which usually takes 3 to 8 weeks. If adequate range of motion is not attained by 3 weeks or motion begins to diminish, hospitalization and remanipulation may be required at postoperative 3 weeks and the postoperative protocol may need to be restarted. If loss of motion persists, an additional surgery may be required to release the reaccumulation of arthrofibrotic tissue.
A number of case reports have recently detailed nerve injury after debridement in elbow arthroscopy (4,5). Ruch and Poehling (4) in 1997 reported an anterior interosseous nerve injury that occurred in a 65-year-old woman with rheumatoid arthritis during elbow arthroscopic debridement and synovectomy. Recently, a case was reported of a complete transection of the median and radial nerves during arthroscopic capsular release in a 57-year-old woman with posttraumatic elbow stiffness. This required open exploration and nerve grafting subsequently (5). These case reports illustrate the inherent neurovascular risks undertaken with arthroscopic release of the stiff elbow.
Attention to bony landmarks and knowledge of the anatomy of the elbow become increasingly important for the arthrofibrotic elbow. The medial epicondyle and medial intramuscular septum are usually preserved in most cases of elbow flexion contracture and therefore serve as a useful guide for initial entrance into the joint. The anterolateral portal can then be created using an inside-out technique under direct visualization with a Wissinger rod, which allows for safer lateral portal placement and protects the posterior interosseous nerve. Also, in patients with lateral elbow trauma or contracture secondary to radiocapitellar injury, lateral capsular contracture may exist that binds the posterior interosseous nerve, increasing risks during portal placement. In cases of elbow flexion contracture developing after fracture or fracture dislocations, it becomes increasingly important during posterocentral portal placement to ensure that the incision is directly over the olecranon fossa to avoid injury to the ulnar nerve.
The elbow capsule is in close relation to the brachialis muscle and neurovascular structures. The brachialis lies between the capsule and anterior neurovascular structures and thus serves as a guide during anterior capsular release. During arthroscopic capsular release care must be taken to release the capsule up to the point of brachialis fibers, but no further. It is helpful to keep the shaver blades and the arthroscopic instruments in proximity to the anterior aspect of the distal humerus and not farther distally, because this may lead to increased risk of brachialis muscle penetration and subsequent neurovascular injury. Proximally, the radial nerve courses between the brachioradialis and brachialis muscles. At the level of the elbow joint, the posterior interosseous nerve branches from the radial nerve coursing laterally to the brachialis and becomes immediately adjacent to the anterior joint capsule in the distal portion of the elbow joint. In cases of capsular contracture secondary to lateral joint injury, the posterior interosseous nerve may be displaced or tightly tethered to the anterolateral capsule. Also, during all arthroscopic procedures about the elbow, the surgeon should be constantly cognizant of the location of the ulnar nerve.
Arthroscopic Capsular Release
Several authors have reported their results of arthroscopic treatment for elbow joint for arthrofibrosis (6–9) (Table 1). In 1998 Phillips and Strassberger (6) reported the results of 25 patients who were treated with arthroscopic debridement. Their series comprised 15 patients who had posttraumatic elbow stiffness and 10 who had contractures secondary to osteoarthritis. At 18 months' follow-up, all patients had increased motion and decreased pain. The average arc of motion improved from 87° before surgery to 128° after surgery. In 1994 Byrd (7) also reported the results of treatment of elbow arthroscopy for posttraumatic stiffness after type I radial head fractures. Five patients were treated with arthroscopic debridement of the radiocapitellar joint with good results and no complications. In 1994 Timmerman and Andrews (8) published their results of arthroscopic treatment of posttraumatic elbow pain and stiffness. They demonstrated good and excellent overall results in 79% of patients treated with arthroscopic debridement. Kim et al. (9) in 1995 reported their results of 25 patients with limitation of motion in the elbow joint caused by intra-articular stiffness. These patients were treated with arthroscopic removal of loose bodies, excision of osteophytes, abrasion arthroplasty, anterior capsular release, and partial excision of the radial head. They showed an improvement in extension of 7° and in flexion of 17°. The average improvement in total range of motion was 24°. From these studies it may be concluded that elbow arthroscopy with debridement is a useful treatment option for posttraumatic elbow contracture. However, follow-up in most of these series averaged only 2 years, indicating that long-term results of arthroscopic treatment remain unknown.
In 1993 we published our initial results with arthroscopic capsular release for elbow flexion contracture (10). The technique at that time was an anterior capsular release followed by debridement of the olecranon fossa. After surgery the mean flexion contracture in this series of 12 patients improved from 38° to 3°. Supination improved from 45° to 84° and pronation from 80° to 88°. Patients reported decreased pain and improved motion. However, in this series, there was one permanent posterior interosseous nerve palsy. Subsequently, we reported the results of our first 53 patients treated with these techniques. The average preoperative flexion contracture was 46°, and was reduced to an average of 5° after surgery (11). In these patients maximum flexion was increased from 96° to 138°, pronation from 75° to 82°, and supination from 47° to 86°. The arthroscopic procedure failed in two patients. One patient eventually required repeat capsular excision and failed to maintain motion, which was regained with the second procedure. The second patient presented with a fixed 90° flexion contracture that was improved to a range of motion of 30° to 125°, but was noncompliant with postoperative therapy. This was also considered a failure.
Arthroscopic Radial Head Excision and Ulnohumeral Arthroplasty
We recently reported our results using arthroscopic ulnohumeral arthroplasty in the management of the arthritic elbow (12). This study comprised 24 patients with painful, restricted elbow motion due to an arthritic process who were treated with the arthroscopic modification of the open Outerbridge–Kashiwhei procedure. Average preoperative flexion was 90° and an average extension loss was 40°, with the average preoperative total arc of motion being only 50°. These patients were treated with elbow arthroscopy combined with debridement, partial resection of the coronoid and olecranon processes, and fenestration of the olecranon fossa. In 18 of 24 patients the radial head was excised arthroscopically. Mean follow-up was 32 months. All patients had a significant decrease in pain, as indicated by the visual analog scale. The average extension was improved to −8° and average flexion to 139°, resulting in overall arc of motion of 131°. The average improvement in elbow motion after the arthroscopic procedure was 81°. From this series, it may be concluded that arthroscopic ulnohumeral arthroplasty is a viable and reasonable treatment option in the management of the arthritic elbow, serving as an intermediate procedure between arthroscopic debridement and total elbow arthroplasty.
The results of arthroscopic treatment compare favorably with those of open techniques (Table 2). Urbaniak et al. (13) reported their results in 15 patients treated with open release for elbow contracture using anterior capsulotomy. The mean flexion contracture improved from 48° to 19°. However, 8 of the 15 patients actually lost flexion when treated with this technique. In a second series of 18 patients treated with a similar technique and the use of postoperative continual passive motion, flexion was diminished in only 1 of 18 patients using the anterior approach.
Other authors have reported good results for open release of elbow contracture through a limited lateral approach (14,15). In a study by Husband and Hastings (14), the lateral approach was used for release of posttraumatic elbow contractures in seven patients with a 38-month follow-up. This technique involved excising the lateral ligament complex. They reported improvement in extension from 45° to 12° after surgery and the mean improvement and maximum flexion for 116° to 129° after surgery. Cohen and Hastings (15) recently reported on the lateral approach for release of posttraumatic elbow stiffness in 22 patients. In their series, a modified technique that spared the lateral collateral ligaments was employed. At an average follow-up of 26 months, the average elbow arc of motion improved from a mean of 74° to 129° with forearm rotation improving from a mean of 135° to 159°. Pain was diminished and elbow function improved after surgery. Advantages to this approach include a more simple surgical procedure with less morbidity and unrestricted postoperative rehabilitation, because the lateral collateral ligaments and common extensor tendon origin are spared. This approach uses an anterior and posterior capsulectomy and occasional radial head resection if indicated.
In comparing open and arthroscopic results for the treatment of elbow stiffness, it appears that both techniques can achieve satisfactory results when employed properly. It is also important to emphasize that neither technique reliably regains the last 10° of elbow extension. Complete arthroscopic evaluation is also useful diagnostically and for removal of occult loose bodies. When the radiocapitellar joint is arthrofibrotic, deformed, or has significant arthritis, arthroscopic radial head excision can be performed concomitantly. Because the release is done arthroscopically, collateral ligament stability is not compromised and morbidity from surgical dissection is minimized. With appropriate technique and awareness of the cause of the contracture, arthroscopic techniques can be safely implemented for good results in the management of the stiff elbow. Arthroscopic capsular release is a technically demanding procedure that requires meticulous attention to detail and should only be attempted by surgeons with extensive experience in elbow arthroscopy.
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