Flexor Tenolysis Periprocedural Care

Updated: Sep 13, 2021
  • Author: Cato T Laurencin, MD, PhD; Chief Editor: Harris Gellman, MD  more...
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Periprocedural Care

Preprocedural Planning

Imaging studies

The major utility of imaging studies prior to flexor tenolysis is to evaluate whether the patient has a failure of tendon reconstruction, elongated callus, or tendon adhesions that lead to the clinical presentation. [12]

Initially, radiographs should be taken to ensure proper anatomic alignment of the skeletal elements. [3]  Ultrasonography (US) has proved effective for assessing both the presence and the location of a ruptured tendon repair. [13, 14]  Additionally, the mechanism of US allows dynamic assessment of flexor tendon injuries; accordingly, this modality is recommended for evaluation of zone 1 (distal interphalangeal [DIP] joint) tendon injuries.

US is not, however, effective for distinguishing pure adherence from elongated callus and thus for determining the type of surgical intervention required. [12]  Additionally, US of the ligaments in zone 2 (metacarpophalangeal [MCP] and proximal interphalangeal [PIP] joints) is a difficult endeavor and is strongly operator-dependent. [12]

Magnetic resonance imaging (MRI) has proved to be effective as a noninvasive imaging procedure to differentiate between tendon rupture and tendon adhesions in zone 2. [12]  Imaging artifacts from implanted devices, including metal plates or screws, can limit the effectiveness of MRI in evaluating tendon injuries.

Histologic findings

In a rabbit model of tendon repair, once a tendon is injured, within 24 hours a noticeable increase in cellularity, predominantly from neutrophils, is seen. In the same model, cells in the tendon sheath are seen to migrate into the tendon, and cells from the periphery of the tendon are seen to migrate to the interior of the tendon core within 7 days. [5]

By 7 days, alpha smooth-muscle actin expression is high, which marks the presence of myofibroblasts and pericytes in the wound area. [5] From 7 to 21 days, cells are both depositing and remodeling collagen bundles, which correlate with a peak in heat shock protein 47 around day 21. As intrinsic healing of affected tendons progresses, alignment of collagen fibers along the axis of contraction, as well as a decrease in inflammatory cellularity, is usually seen, with a peak in apoptosis around 84 days in rabbits. [5, 12]

In human subjects, studies that closely track cell origin and type are lacking, but when histologic sections of adhesions are examined, noninflammatory cells resemble myofibroblasts and secrete types I and III collagen, and epitenon cells are also involved in the process of both collagen production and collagen debris clearance.


Patient Preparation

Since the 1970s, flexor tenolysis has been popularly performed with local anesthesia alone. [15]  One benefit of this approach is that the surgeon may engage actively with the patient to ensure that the tendon is free from adhesions and can glide easily in the tendon canal. Active participation from the patient also establishes whether the musculature for digit flexion is strong enough to power tendon contraction. There is increasing interest in performing flexor tenolysis via the WALANT (wide awake, local anesthesia, no tourniquet) approach. [16, 17, 18]

General anesthesia can still be considered for patient-specific factors, including irritability, anxiety, or a complicated surgical plan owing to multiple affected tendons. Under circumstances of general anesthesia, active flexion can be ascertained by opening a surgical window proximal to the affected tendon as described by Whitaker et al. [19]  Using this opened window, surgeons can pull on the tendons to simulate muscular contraction.