14 Stiffness in the Extensor Tendon
14.1 Patient History Leading to the Specific Problem
A 44-year-old male patient presents with a stiff left index finger. He had suffered an injury with a circular saw about 3 months earlier. The middle slip of the extensor tendon of the finger had been avulsed together with some bone fragments. The fragment had been reattached and the extensor tendon as well as the surface of the proximal interphalangeal (PIP) joint had been reconstructed (▶Fig. 14.1). Despite extensive postoperative physical therapy, range of motion was severely reduced in the proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints, respectively (▶Fig. 14.2).
14.2 Anatomic Description of the Patient’s Current Status
Stiffness of finger joints is one of the most common complications after any type of injury or surgery of the hand. Detailed knowledge of tendon and joint anatomy and a thorough analysis of the individual situation are mandatory to develop a treatment plan for any patient presenting with stiffness of the fingers.
There are many reasons for limited flexion of the PIP joint such as edema, lack of or contractures of the overlying skin, adhesions of the extensor tendons to skin or bone, contracture or adhesions of the palmar plate, and incongruence of the joint surfaces or mechanical blocks such as exostoses. Most of the times, combinations of these will be present; therefore, it is often very hard to determine the full extent of a possible operative procedure beforehand. While alterations of the bony structure can easily be detected by common X-ray studies, soft tissues must be assessed by clinical examination. At times, it can be even quite difficult to determine whether the pathology is located on the flexor or extensor side of the finger, or both.
Fig. 14.1 (a, b) Preoperative X-ray studies immediately after injury. Notice the boutonniere deformity after detachment of the central slip. (c, d) X-ray studies 12 weeks after the initial injury. The central slip was reattached and the joint surface was reconstructed.
Fig. 14.2 (a) Clinical findings after the initial procedure with bony healing but stiffness of proximal interphalangeal joint in extension contracture. (b) Test for intrinsic tightness. Range of motion does not change with the metacarpophalangeal joint held in flexion, indicating the lack of intrinsic tightness.
Most importantly, active and passive ranges of motion of the PIP joint must be examined in different positions of the metacarpophalangeal (MCP) joint. Range of motion was determined as 0/25/35 degrees for the PIP joint according to the neutral-0 method for both, active and passive movements. There was no substantial movement of the DIP joint. Because the patient had suffered an injury to the extension side of the finger and demonstrated similar active and passive range of motion, adherence of the extensor tendon and possible extension contracture of the PIP joint were the most probable causes of the limited range of motion. Since the injury involved both substantial soft-tissue trauma and fractures of the middle phalanx, broad adhesions of the extensor tendon with the overlying skin and underlying bone had developed. Range of motion for the PIP joint was independent of the position of the MCP joint, indicating the lack of intrinsic tightness (▶Fig. 14.2).
Correct timing of secondary surgery on stiff fingers is of utmost importance. Rather than relying on rigid time frames, one should make sure that a number of requirements are met before attempting revision surgery. There must be adequate soft-tissue coverage allowing for the preparation of well-perfused flaps above tendons and joint surfaces. Swelling must be gone and scars should be supple. Splinting, physical therapy, and other conservative therapy options should have been exhausted and the patient should have reached a plateau of range of motion with no further improvement. These requirements are usually not met before 3 to 6 months after surgery. Furthermore, the patient must be aware of and willing to perform extensive postoperative physical therapy for several weeks after the operation. It has been indicated that surgery after a delay of a year or more will lead to less favorable results, possibly because of more rigid joint contractures.
Wide-awake or WALANT (wide-awake local anesthesia, no tourniquet) surgery describes an operative technique in which anesthesia is achieved only by lidocaine and epinephrine. Patients are able to move their fingers throughout the procedure and do not have to endure a tourniquet. This form of surgery is ideal especially for tenolysis, because the success of the procedure is immediately visible to both surgeon and patient.
14.3 Recommended Solution to the Problem
• WALANT surgery to intraoperatively check for active range of motion.
• Separation of adhesions between the central slip and both overlying skin and underlying bone.
• Possibly arthrolysis of the PIP joint.
See ▶Video 14.1.
Approximately 30 minutes before the operation, an appropriate amount of tumescent local anesthetic is administered (▶Fig. 14.3). Usually, we prefer a mix of 1% lidocaine with 1:100,000 or 1:200,000 epinephrine injected directly into the presumed operative field. A combination of nerve blocks and direct infiltration may be used. It is important to estimate the maximum extent of surgery beforehand, because vasoconstriction takes about 30 minutes to properly set in. You can always numb up additional regions during surgery, but most of the time there won’t be sufficient vasoconstriction and surgery can become exceedingly difficult in regions such as the palm of the hand because of diffuse bleeding. If possible, additional sedation should be avoided to ensure a fully cooperative patient during tenolysis. The patient is then placed in a supine position and prepped appropriately.
The skin is incised and skin flaps are created by dissection in the plane between the tendon or peritendineum and subcutaneous tissues (▶Fig. 14.4a). It is important to stay in the correct plane, because otherwise either skin viability will be compromised or the tendon is weakened or damaged. The integrity of the tendon is assessed and cautiously protected as well as its insertion at the middle phalanx. In a similar fashion, the tendon is separated from the underlying bone (▶Fig. 14.4b). After freeing the tendon proximal to the PIP joint, the tendon is assessed and, if necessary, released distal to central slip insertion (▶Fig. 14.4c). Dissection should be continued until all adhesions around the extensor tendon are released. Passive range of motion is assessed. If the PIP joint is contract, stepwise release of the PIP joint must be performed. The extensor tendon is elevated and the dorsal joint capsule and collateral ligaments are exposed. The first step is to incise the dorsal joint capsule. If easy flexion of the PIP joint is still not possible, both accessory collateral ligaments are carefully incised in a dorsal-to-palmar fashion, until easy passive flexion is achieved. The patient is then asked to actively flex the joint (▶Fig. 14.4d). In this way, minor adhesions that still limit function can be ruptured. At the end of the procedure, active and passive flexion should be as close to full range of motion as possible. Sometimes, patients will have difficulties moving a numb finger without visual control. If possible, the drapes should be lowered and the resulting range of motion demonstrated to the patient. Most of the time, the patient will be very impressed. We strongly encourage demonstrating the results to the patient, because it helps motivate postoperative therapy. The skin is closed with narrow interrupted sutures and range of motion is finally assessed one more time before putting a light bandage on. The patient is encouraged to move the joint right away.