Introduction

Elbow stiffness is a relatively common condition and represents a significant disability. There are multiple causes of loss of elbow range of motion. Therefore, a proper clinical history is important for therapeutic surgical or non-surgical planning.[1]

Etiology

Its etiology is considered to be multifactorial, including post-traumatic arthritis, heterotopic ossification, non-union or malunion with soft tissues around the elbow contracture. Regan and Reilly recognized three factors that may contribute to elbow contracture: 1) its complex anatomy, 2) the anterior brachial muscle that covers the anterior capsule leading to ossification and 3) sustained immobilization due to difficulties in achieving a stable osteosynthesis, especially in complex fractures.

Elbow stiffness is mainly determined by the degree of the joint injury. However, it is also influenced by periosteum loss and immobilization time. These causes may explain why major contractures are observed, despite obtaining adequate reduction and stability, or even in fractures without displacement. Other non-traumatic causes of stiffness are hemophilia, sequelae of infections, rheumatoid arthritis, and osteoarthritis. Among congenital causes, the arthrogryposis and congenital dislocation of the radial head are distinguished.

Stiffness due to Heterotopic Ossification

These formations of mature bone in non-bony locations frequently present in the elbow. Its cause remains unknown. Amorphous calcium deposits that affect the capsule and the collateral ligaments may consolidate in periarticular calcifications. Distinguishing this phenomenon from the heterotopic ossification is important.   

Heterotopic ossification presents after direct elbow trauma. Post dislocation incidence rises 3% according to literature reports, and up to 20% is associated with fractures and complex dislocations. They occur in 5% to 10% in patients with isolated encephalic trauma, more frequently on the hemiplegic side. When encephalic trauma occurs together with elbow trauma, the percentage reaches to 75% to 90%. They have also been associated with specific surgical approaches. Available medical treatment is not completely effective; therefore prevention is a key element. The utility of NSAIDs was demonstrated during the first 3 to 5 days of its development. Indomethacin, ibuprofen, naproxen, and aspirin have proved to be the most effective.

Elbow Stiffness Secondary to Malunion and Nonunions

The particular etiology will determine the treatment of these entities. It can originate as a sequel of articular fractures and malunions. These conditions disrupt the elbow biomechanics. No union of the distal humerus produces limitation due to pain and instability.  In these cases, in addition to the treatment of nonunion, procedures, such as arthrolysis, should be added. It is important to evaluate the complete affected limb and identify any associated injuries, such as burns, infections, and neurovascular lesions, among others.

Epidemiology

The loss of elbow mobility after a traumatic event occurs in 5% of cases.

Pathophysiology

Acute or repeated traumas represent the most frequent causes of elbow stiffness. Extension loss is more common than flexion loss.[2][3]

Cellular events occurring after trauma and its implications in stiffness are currently being studied. Participation of relaxin in capsular laxity together with the increase of cross-collagen bridges and decreased proteoglycans and water content are findings involved in an abnormal tissue of induced contractures.

Decrease range of motion depends on factors related to the type of joint trauma and soft tissue, treatment, rehabilitation and patient response. During the evaluation, it is important to consider previous surgeries, type of initial trauma and surgery, an affection of soft tissue, time of immobilization, and type of rehabilitation.[4]

History and Physical

The normal arc of flexion-extension is 145 degrees (0 to 145 degrees), and 75 to 85 degrees for pronosupination. An arc of movement between 30 and 130 degrees in flexion-extension and 50 degrees in pronosupination provides sufficient range for most daily life activities. It is important to individualize the degree of compromise in the range of motion, because it may vary through activity level. For example, an arch suitable for most of the general population may not be sufficient for athletes and musicians.

Pain is rare in stiffness. It may be present during flexo-extension when related to arthritis and at rest during infectious process. 

Heterotopic Ossifications

Local inflammation, pain, and an increase in local temperature are the most common manifestations. This inflammatory phenomenon should not be confused with an infection. Pain may not always be present and usually appears at the end of the arc of movement. Regarding laboratory findings, decreased calcium and increased phosphates may be observed. Serum alkaline phosphatase rises between 2 and 4 weeks after the beginning of the symptoms and reaches 3 or 4 times above normal limit after 3 to 10 months. Bone centellogram with TC 99 shows increased metabolic activity during the first week and is prolonged for one year. X-rays are the adequate study for evaluation and monitoring. Mature bone is described as well-defined cortical presence. This maturation usually occurs after 3 to 5 months, after which it is possible to proceed with a surgical approach.

Evaluation

Anteroposterior (AP) and lateral x-rays are useful in most cases. When the decrease range of motion is 45 degrees or greater, the AP incidence is difficult to obtain. CT scan is useful in sequelae of complex fractures and when there are doubts about treatment planning.

Classification

For an optimal evaluation and understanding of the eventual treatment, stiffness can be classified as:

• Extrinsic, without joint affection (ligaments, muscular and capsule)
• Intrinsic, with compromise of the articular surface, possibly due to adhesions, osteophytes, chondrolysis, or trauma
• Mixed: combined intrinsic with extrinsic injuries. These are more frequent. Most of the times, intrinsic causes envolve to an extrinsic stiffness.

According to the arc of movement (flexion, extension), stiffness can be classified in mild, less than 90 degrees of range, moderate between 60 to 90 degrees,  serious between 30 to 60 degrees and severe less than 30 degrees.

The following guide has been proposed to differentiate simple from complex contractures. Simple compromise should meet the following features: 

1. Mid or moderate contracture: the movement range of 80 degrees or greater
2. Non-existent or minor previous surgery
3. Without prior transposition of the ulnar nerve
4. Without osteosynthesis or minimum material
5. Without heterotopic or minimal ossifications
6. Normal bone anatomy.

If at least one of these criteria is absent, the contracture is considered complex.

Differential Diagnosis

• Congenital contractures found in arthrogryposis

• Congenital radial head dislocation

• Inflammatory arthritis

• Multiple hemarthroses in haemophiliacs

• Osteoarthritis

• Post-septic arthritis

Pearls and Other Issues

The incidence of surgical complications varies depending on the causes of the contracture and its complexity, from 10% to 30%. Hematoma, infections, ulnar nerve neuritis, ossification, hypertrophic scars, and pain are the most frequent complications of the procedures. Late ulnar neuropathy has recently been observed due to elongation after recovering degrees of extension in flexion contractures. Iatrogenic neurological injuries have been reported in both, open techniques and arthroscopic procedure. However, its frequency depends on experience and complexity. The following suggestions have been proposed to diminish the risk of complications: use of retractors, avoid the aspiration near the nerves (disconnect the shaver), careful use of the shaver close to the nerves to avoid traction and recognizing surgeons limitations regarding the surgical experience.[15]

Enhancing Healthcare Team Outcomes

Stiff elbow is best managed by an interprofessional team that includes a therapist and an orthopedic nurse. In most cases, conservative treatment with exercise is the first step. Surgery is often undertaken for recalcitrant conditions that do not respond to conservative measures. However, surgery does not guarantee a positive result and is also associated with serious complications.

The outcomes for patients with stiff elbow depend on the cause. Those who comply with rest, stretching and regular exercise tend to have good outcomes.