Tenolysis: Flexor and Extensor

Gleb Medvedev, MD

Elisa J. Knutsen, MD

Neither of the following authors nor any immediate family member has received anything of value from or has stock or stock options held in a commercial company or institution related directly or indirectly to the subject of this article: Dr. Knutsen and Dr. Medvedev.

Introduction

Trauma to flexor and extensor tendons can cause adhesion formation that inhibits motion. Early motion therapy protocols following tendon injury are aimed at disrupting these adhesions. However, when the results of therapy have been exhausted, tenolysis is a salvage procedure to remove those adhesions and improve motion. Tenolysis should not be undertaken lightly since it is another insult to an already traumatized finger, and carries the risk of tendon rupture as well as decreased innervation and blood supply to the previously injured digit. Following tenolysis, the patient must be active in the postoperative treatment at home and with the therapist. To that end, the patient must demonstrate a history of compliance with therapy prior to tenolysis, and have confirmed access to a hand therapist. Before proceeding to tenolysis, the patient must have anatomically aligned and healed fractures, coverage of any open wounds with soft and supple skin, intact tendons, good muscle strength, and near full passive range of motion (ROM).

Flexor Tenolysis

Indications

Flexor tendons need to be able to glide within the flexor tendon sheath to function properly. Adhesions, which form as part of the healing process following trauma—such as a crush injury, infection, or laceration of the tendon—interfere with tendon gliding and can cause loss of motion. The indication for tenolysis is decreased active flexion ROM compared to passive flexion in patients who have reached a plateau in their rehabilitation. The timing of tenolysis is generally 3 months after the injury or tendon repair, with a 4- to 8-week plateau of progress in hand therapy. This allows adequate time for healing of tendon repairs and softening of the covering tissues. Other prerequisties to tenolysis include healing of all finger fractures, mobilization of joint contractures, and the patient must be compliant and motivated to actively participate in the postoperative rehabilitation. The decision to proceed with tenolysis should be made in conjunction with the patient based on the patient’s expectations and other factors, such as his or her functional demands and other concominant injuries or arthritis of the hand or digit.

Procedure

Local anesthesia, either a regional block or subcutaneous infiltration, is recommended with use of intravenous sedation and analgesics. This allows for patient interaction with active flexion examination at the conclusion of tenolysis.

The procedure is performed through wide exposure of the flexor tendon using a Bruner incision or a midlateral incision. The approach is often dictated by prior wounds and incisions. During dissection, care is taken to preserve the annular pulleys, especially the A2 and A4, to prevent bowstringing. Next, the flexor tendons are identified and the superficialis and profundus are separated. This can be achieved through multiple transverse windows in the retinaculum and by using special tenolysis knives, elevators, or braided suture to release adhesions (Figure 30.1). If a flexor tendon repair was performed, the site should be examined and débrided as needed to allow for smooth tendon gliding. If more than 30% of the width of the tendon is lost or if the tendon is not in continuity, then staged reconstruction must be pursued.

Once tenolysis is achieved along the entirety of the tendon in the digit and palm, the patient under local anesthesia can be asked to actively flex the digits. Under general anesthesia, it is necessary to create a separate proximal incision and manually pull the tendons for a “traction flexor check.”

Complications

Complications from tenolysis include wound healing problems and failure to maintain motion due to recurrent adhesions. Tendon rupture is infrequent but obviously a disastrous complication that requires either staged reconstruction or repair, depending on the tendon quality.

Figure 30.1 Illustration of flexor tenolysis performed by identifying the scarred tendon and sheath (A), followed by release of adhesions and careful preservation of the pulley system (B). C, Release may be facilitated by passing a small elevator or dental probe through windows in less critical portions of the sheath (e.g., proximal to A2, or between A2 and A4 pulleys). (Reproduced with permission from Strickland JW: Flexor tenolysis, in Strickland JW, ed: Master Techniques in Orthopaedic Surgery: The Hand. Philadelphia, PA, Lippincott Raven, 1998, pp 525–538. Illustrations copyright © Gary Schnitz and the Indiana Hand Center.)

Postoperative Rehabilitation

Dedication to vigorous and early therapy is necessary to keep gains made intraoperatively, and is dictated by the quality of the tendon after tenolysis. For frayed tendons, we recommend focusing on active place-and-hold exercises (explained later) initially with full active extension, but avoiding active flexion exercises for 4 weeks postoperatively. This should minimize the risk of rupture while maintaining as much tendon excursion as possible.

Postoperative pain control is crucial for patient participation in therapy. Occasionally, a regional block catheter can be left in place postoperatively for up to 5 to 7 days to facilitate immediate therapy participation. A number of variables can make pain control difficult, including edema and the pain from the extensive dissection.

For patients with normal or near-normal tendons after tenolysis, an immediate motion protocol is started within 12 to 24 hours after surgery. The therapy regimen should include edema control, wound management, active range of motion (AROM) and passive range of motion (PROM), and a home exercise program. As the patient progresses, these elements should be advanced or modified to maintain and increase motion and strength.

Active Range of Motion

AROM is begun immediately with the goal of replicating intraoperative motion at the first therapy visit.
“Place-and-hold” tendon gliding exercises is the method of placing the digits passively into a position and having the patient actively hold that position. Three positions are maintained: slight, moderate, and maximal finger flexion. This exercise is performed by using the nonoperative hand to place the operative hand in the desired position, which is then held with the muscle power of the operated hand. It requires activation and excursion of the flexor tendons to maintain position without high tension on the tendons. In the initial weeks, this exercise is more tolerable than tendon gliding exercises.
Tendon gliding exercises are AROM that prevent adhesion formation between the flexor digitorum superficialis and profundus tendons by providing maximal differential gliding. They are performed by flexion of the fingers through a set of positions: (1) straight hand, (2) hook fist, (3) table top, (4) straight tip fist, and (5) full fist (Figure 30.2). As the patient advances, the patient may begin performing these exercises with the wrist in flexion and in extension to increase excursion of the tendons.
Blocking exercises are started within the first week to isolate motion at individual joints and tendons. First, the metacarpophalangeal (MCP) should be held in extension and perform active proximal interphalangeal (PIP) motion. Then, hold (or block) the distal interphalangeal (DIP) joint in extension while actively flexing the DIP joint
(Figure 30.3). This will direct excursion of the tendon to the unblocked joint.

Figure 30.2 Illustrations of tendon gliding exercises: Straight hand (A), hook fist (B), table top (C), straight tip fist (D), and full fist (E).

Passive Range of Motion

PROM is a useful adjunct for patients who have concurrent joint contractures.
PROM exercises that isolate each joint (MCP, PIP, and DIP) should be performed in addition to composite motion.
Care must be taken not to be overly vigorous, as this can cause pain and incite inflammation.

Edema Control

Edema and swelling can decrease ROM and increase pain, making cooperation with therapy difficult.
Elevation of the operative hand above the level of the heart is an effective means to decrease edema.
Overhead exercises, such as fist pumps, can achieve both ROM and edema control.
Coban, lightly wrapped in a figure-of-eight pattern from distal to proximal, can also be used to control edema.
Bulky dressings should be removed prior to performing exercises.

Home Program

Exercises should be performed hourly during waking hours with 5 to 10 repetitions each.
After sutures have been removed, patients should also start deep friction scar massage in line with the incision several times a day to soften the scar and improve tissue mobility.

Splinting