Steroid Injection Using Tendon Excursion for Trigger Finger: Introduction to Injection Methods and Analysis of Treatment Results

Purpose: Local corticosteroid injections are routinely used as first-line treatment for trigger finger. However, accurate delivery of steroids into the tendon sheath is important for the effectiveness of the treatment and the prevention of complications. This study aimed to introduce our steroid injection technique for trigger finger, which uses tendon excursion of the flexor tendon, and evaluate the clinical outcomes in patients who were treated with this technique.Methods: A total of 171 patients with trigger finger who were treated with steroid injections were retrospectively reviewed. The efficacy of injection and complications were investigated. The evaluation of the efficacy was classified into “good,” “fair,” and “poor.” The results were analyzed according to the type of finger and the Quinnell grading system.Results: The total efficacy was 83.6% (good/fair, 143 digits; poor, 28 digits). The treatment success rate for Quinnell grade IV was 43.8% (7 of 16), which was significantly lower than those of Quinnell grades II and III, which were 88.9% (88 of 99) and 87.5% (49 of 56), respectively (II vs. IV, p=0.004; III vs. IV, p=0.010). In four fingers (excluding the thumb), the success rate was significantly higher than that of the thumb (88.2% vs. 75.4%, p=0.048).Conclusion: The steroid injection technique using tendon excursion showed excellent results and low complication rates. In particular, the second to fourth fingers and low-grade fingers showed more effective results.

Soft tissue inflammatory disorders of the hand

Soft tissues are an important interface between the tendons and bones of the hand. This interface provides both physical and biological functions by facilitating smooth tendon excursion, tendon healing, and tendon and joint stability. Disease of these soft tissues results in pain, swelling, and loss of function, and can be due to systemic conditions or local factors. These conditions include disease of the tendon sheath, disease of the tendon synovium, and diseases of tendon attachments. Inflammation was considered a universal hallmark in these conditions but recent evidence suggests that this is not true for all such conditions, whose treatment has consequently been modified. This knowledge has also caused reflection on the nomenclature used to describe these conditions and has brought clarity to the traditionally used terminology such as tenosynovitis.

Effects of wrist extension on median nerve and flexor tendon excursions in patients with carpal tunnel syndrome: a case control study

Background Reduced gliding ability of the median nerve in the carpal tunnel has been observed in patients with carpal tunnel syndrome (CTS). The purpose of this study was to evaluate the gliding abilities of the median nerve and flexor tendon in patients with CTS and healthy participants in the neutral and 30° extended positions of the wrist and to compare the gliding between the finger flexion and extension phases. Methods Patients with CTS and healthy participants were consecutively recruited in a community hospital. All the subjects received the Boston CTS questionnaire, physical examinations, nerve conduction study (NCS), and ultrasonography of the upper extremities. Duplex Doppler ultrasonography was performed to evaluate the gliding abilities of the median nerve and flexor tendon when the subjects continuously moved their index finger in the neutral and 30° extension positions of the wrist. Results Forty-nine patients with CTS and 48 healthy volunteers were consecutively recruited. Significant differences in the Boston CTS questionnaire, physical examination and NCS results and the cross-sectional area of the median nerve were found between the patients and the healthy controls. The degree of median nerve gliding and the ratio of median nerve excursion to flexor tendon excursion in the CTS group were significantly lower than those in the healthy control group in both the neutral and 30° wrist extension positions. Significantly increased excursion of both the median nerve and flexor tendon from the neutral to the extended positions were found in the CTS group. The ratio of median nerve excursion to flexor tendon excursion was significantly higher in the finger flexion phase than in the extended phase in both groups, and this ratio had mild to moderate correlations with answers on the Boston CTS Questionnaire and with the NCS results. Conclusions Reduced excursion of the median nerve was found in the patients with CTS. The ratio of median nerve excursion to flexor tendon excursion was significantly lower in the patients with CTS than in the healthy volunteers. The median nerve excursion was increased while the wrist joint was extended to 30° in the patients with CTS. Wrist extension may be applied as part of the gliding exercise regimen for patients with CTS to improve median nerve mobilization.

Finite element analysis of the flexor digitorum profundus tendon during a passive rehabilitation protocol

The present study aims to create a patient-specific hand model to simulate the passive rehabilitation on the index finger, quantifying the flexor digitorum profundus (FDP) tendon excursion and the stress experienced during simulated flexion. The computational model used in this analysis was created from an unknown patient dataset available in the Embodi3d online library. The segmentation, three-dimensional reconstruction, and modeling of the structures involved were performed using Materialise Mimics and Rhino3D. The FDP tendon excursion and stress values present in the model were calculated in the ANSYS environment. Based on the finite-element simulation, the FDP tendon presents an excursion of 10.1 mm during passive postoperative flexion. The highest-stress values were observed between the pulleys-FDP tendon contact surfaces. In particular, the pulley A1 exhibited the maximum principal stress of the model with a 58.7 MPa. The pulley A3 showed the same stress distribution pattern that A1 Pulley, but with the lowest values. The FDP Tendon excursion obtained is consistent with the results reported in the literature, which vary from 8 to 11 mm. The stress values found in the model explain the importance of the pulley mechanism keeping the FDP tendon attached to the finger bone during the range of motion experienced. The silico model proposed may potentially be used in the assessment of new medical device proposals in the field of hand reconstructive surgery.

Functional anatomy of the sagittal bands and mechanisms of extensor tendon dislocation: a cadaveric study

We investigated the functional anatomy of the radial sagittal band and possible mechanisms involved in its spontaneous and traumatic rupture using seven cadaveric hands. First, the extensor tendon excursion and the change in angle between the sagittal bands and the tendon path were measured during metacarpophalangeal joint flexion. The radial bands were then divided in two different ways that mimicked spontaneous or traumatic rupture. We found no significant correlation between the extensor tendon excursion and the change in angle of the sagittal bands in the middle and ring fingers. Dislocation could occur when the radial sagittal band was only partially divided. This may explain why conservative treatment of tendon dislocation in the middle and ring fingers is feasible. Complete section of the sagittal bands in the little finger caused ulnar dislocation of the extensor tendon in only one out of seven hands.

Extensor Tendon Dislocation at the Metacarpophalangeal Joint of Both Ring Fingers Caused by a Specific Hand Posture in a Shiatsu Therapist

A 43-year-old female shiatsu therapist complained of sudden snapping of the metacarpophalangeal joints (MCPjs) of both ring fingers during a specific hand posture. The extensor tendon of the ring finger was dislocated ulnarly when the MCPj of the ring finger was flexed and deviated ulnarly and the MCPj of the middle finger was extended. Surgical exploration revealed an attenuated radial sagittal band. We plicated the juncturae tendinum of the extensor digitorum communis between the middle and ring fingers and released the ulnar sagittal band partially to centralise the extensor tendon excursion. Twenty-six months postoperatively, the patient regained full active and passive range of motion of all fingers without extensor tendon dislocation or snapping in either hand during work.

Flexor Tendon Repair

The disruption and subsequent repair of flexor tendons presents a formidable challenge to the hand surgeon. In an effort to regain excursion of the involved tendons, the definitive outcome depends on a number of variables, including the level of injury, the mechanism of injury, and associated trauma to the skin, pulleys, neurovascular bundles, and bone. The ultimate result, however, is directly proportional to scarring, fibrosis, adhesions, and gap formation that limit the return of normal tendon excursion and the final composite motion of the digit.