Evaluation of flexor pollicis longus tendon attrition using color Doppler imaging after volar plate fixation for distal radius fracture

The use of ultrasound to predict flexor tendinopathy after anterior locking plating of the distal radius

This study compares ultrasound to clinical and radiographic measurements for assessing tendon pathology associated with distal radial anterior locking plates. A total of 46 patients undergoing removal of a distal radial plate had a preoperative clinical examination, radiographs and ultrasound evaluation to detect evidence of tendon irritation. Gross changes to the tendon were assessed during plate removal. In total, 32 patients demonstrated clinical abnormality. Soong 2 position was noted in 13 patients. Ultrasound revealed tenosynovitis in nine patients, tendon fibrillation or thickening in four patients and a single case of partial discontinuity. Intraoperative assessment revealed tenosynovitis in 28 patients and tendon fibre discontinuity in eight patients. Ultrasound findings were not predictive of intraoperative tenosynovitis and discontinuity. A relationship was noted between higher Soong grade, especially grade 2, and intraoperative presence of tenosynovitis, as well as Soong grade and amount of soft-tissue coverage. This study negates our hypothesis that ultrasound is useful for identifying tendinopathy after distal radial anterior plate fixation.Level of evidence: II.

Diagnostic ultrasound of tendon injuries in the setting of distal radius fractures

OBJECTIVE

Describe tendon injuries and their structural causes seen on ultrasound in wrists with distal radius fractures and estimate the accuracy of ultrasound and its impact on clinical management.

MATERIALS AND METHODS

Ultrasounds of 226 wrists (221 patients) with distal radius fractures were retrospectively reviewed. Ultrasound findings of tendon injuries and their structural causes were correlated with surgery and clinical outcome. Accuracy and inter- and intra-observer reproducibilities were calculated.

RESULTS

Twenty-five wrists were treated non-operatively while 201 underwent surgery. Ultrasound demonstrated hardware contact with flexor pollicis longus (FPL) in 76 wrists, extensor pollicis longus (EPL) in 21, and other tendons in 94. Ultrasound identified tendon ruptures in 23 wrists (13 EPL/8 FPL/2 extensor indicis proprius (EIP)), most of which were surgically confirmed. Among 12 wrists with confirmed EPL ruptures, distal radius fracture had been treated with volar plating in 6 and non-operatively in 6, and ultrasound showed osseous irregularity at the rupture site in 8. All FPL ruptures occurred in wrists with volar plating. Ultrasound findings were concordant with subsequent clinical management in most. In 2, ultrasound findings led to the decision to remove hardware despite lack of symptoms. Ultrasound had sensitivity/specificity/accuracy of 88/99/98% for identifying a specific tendon as ruptured and 88/87/88% for tendon abnormalities in general. Inter- and intra-observer reproducibilities were excellent (kappa = 0.85 ~ 1.0).

CONCLUSION

Certain wrist tendons, particularly EPL and FPL, are vulnerable after distal radius fractures. Ultrasound is accurate and useful for detecting tendon injury and sources of tendon irritation and can guide clinical management.

Tendons and Tendon Sheaths of the Hand - An Update on MRI

BACKGROUND

 The tendons of the hand run in close proximity to each other and within retinacular tunnels adjacent to articular joints, while forming intersections in characteristic locations. The enclosing tendon sheaths are often sites of systemic or infectious inflammation.

METHOD

 This review article outlines the different entities of tendon and tendon sheath pathology and their manifestation in the hands. Diagnostic findings in tendon and tendon sheath disorders are illustrated using MRI imaging and discussed in context with the current literature.

RESULTS AND CONCLUSION

 Overuse may cause stenosis in the fibrous outer layer of the retinacula and the A1 annular ligaments as well as tendinosis. In contrast, proliferative tenosynovitis is a disease of the synovial inner layer of the tendon sheath with tendon infiltration and tendinitis. Pyogenic tenosynovitis favors the flexor compartments. Because of the narrow spaces in the hand, a high-resolution MRI technique must be used.

KEY POINTS

  · Diseases of the tendons and tendon sheaths may have a mechanical, degenerative, metabolic, systemic inflammatory, or infectious etiology.. · Fibrous tunnels and bony prominences in close proximity to crossing tendons predispose to mechanical tendon irritation at typical sites of the hand.. · Stenosing tenovaginitis occurs in the fibrous layer of the extensor retinaculum or the A1 annular pulleys. The most frequent manifestations are the "trigger finger" and de Quervain disease.. · Proliferative tenosynovitis affects the synovial layer of the tendon sheaths before infiltrating the tendons. The classic representative is rheumatoid arthritis..

CITATION FORMAT

· Schmitt R, Hesse N, Grunz JP. Tendons and Tendon Sheaths of the Hand - An Update on MRI. Fortschr Röntgenstr 2022; DOI: 10.1055/a-1826-1007.

Trigger thumb preceding flexor pollicis longus tendon rupture after distal radius volar plate fixation: A case report

INTRODUCTION

Flexor pollicis longus (FPL) tendon rupture is a known complication after a distal radius (DR) fracture and subsequent fixation with a volar plate. A commonly accepted theory is the attrition of the flexor tendon by the prominent volar plate or theoretical injury to the tendon during the initial injury. An increasingly rare complication of distal radius open reduction internal fixation (ORIF) with volar plate fixation is stenosing tenosynovitis, more commonly known as trigger finger.

PRESENTATION OF CASE

We present a case of FPL rupture 7 years after volar plate fixation for DR fracture with thumb triggering in an elderly patient. To treat her trigger thumb, a corticosteroid injection was administered for symptomatic relief. Without resolution of her symptoms, she was scheduled for hardware removal and A1 pulley release. At her preoperative visit, she was found to have a rupture of her FPL tendon.

DISCUSSION/CONCLUSION

This case report provides insight into an atypical presentation of delayed-onset FPL rupture and preceding trigger thumb. Especially in individuals with no inciting events, the patient's trigger thumb after volar plate distal radius ORIF may have been a warning sign for impending FPL rupture. This underscores the importance in considering potential tendon attrition as part of a differential diagnosis in a patient presenting with trigger thumb after distal radius ORIF with a volar plate. In assessing for FPL tendon rupture, diagnostic imaging modalities such as ultrasound may be utilized in evaluating this condition to prevent potential loss of function.

Correlation of Flexor Pollicis Longus Tendon Status by Ultrasonography with Plate Position on Radiographs Following Volar Plate Fixation of Distal Radius Fractures with Pronator Quadratus Repair

BACKGROUND

Purpose was to correlate flexor pollicis longus tendon (FPL) attrition using Ultrasonography with plate position on radiographs following volar locked compression plate fixation (LCP) in patients who have undergone pronator quadratus (PQ) repair for distal radius fractures.

METHODS

Status of flexor pollicis longus tendon was analyzed by ultrasonography in patients who underwent volar locked compression plating with pronator quadratus repair at a minimum of one year follow up. Soong's criteria was used to assess the plate position and then correlated the ultrasonography findings of flexor pollicis longus.

RESULTS

There were 33 patients included in our study, of which 15 belonged to Soong's grade zero, 10 were grade one and eight were grade two. Flexor pollicis longus attrition was noted in all cases with grade two plating.

CONCLUSION

Pronator quadratus repair may not prevent attritional changes in higher grades of Soong's, hence follow up may be required in these patients to identify attritional changes and early implant removal to prevent complications.

Ultrasound Evaluation of the Protector Role of the Pronator Quadratus Suture in Volar Plating

The main complication of volar locking plates for distal radius fractures is flexor tendon rupture. The flexor pollicis longus (FPL) is the most commonly ruptured. Repair of the pronator quadratus (PQ) is one of the ways to prevent tendon rupture. The main purpose of this series was to evaluate the role of PQ repair after volar plating to prevent flexor tendon rupture using ultrasound (US). This work was a mono-operator prospective series of 20 consecutive patients with volar locking plates for distal radius fracture between September 2014 and May 2015. The PQ was repaired in all patients. A clinical, ultrasound, and perioperative evaluation of the flexor tendon was performed by this same surgeon. There was no flexor tendon rupture or tenosynovitis. There were no type A cases, which are characterized by contact between the plate and the FPL, and mostly type C cases, which are characterized by no contact between the plate and the FPL on US imaging. The suture of the PQ was sustainable over time when we removed the plate. Pronator quadratus repair is one of the ways to prevent flexor tendon rupture after volar plating. The outward-running suture is an effective technique for repairing the PQ. Ultrasound may be helpful during follow-up to detect asymptomatic flexor tendon irritation.

The Effect of Plate Design on the Flexor Pollicis Longus Tendon After Volar Locked Plating of Distal Radial Fractures

BACKGROUND

Injury to and rupture of the flexor pollicis longus (FPL) tendon are known complications after volar locking plate fixation for distal radial fractures. Recent investigations have demonstrated that plate positioning contributes to the risk of tendon rupture; however, the impact of plate design has yet to be established. The purpose of this study was to compare FPL tendon-to-plate distance, FPL tendon-plate contact, and sonographic changes in the FPL tendon for 2 volar locking plate designs (ADAPTIVE compared with FPL) using ultrasound examination.

METHODS

We identified patients who underwent distal radial fracture fixation by 2 fellowship-trained hand surgeons with either standard (ADAPTIVE) or FPL plates. Patients were matched by age, sex, and Soong grade. Enrolled patients returned for a research-related office visit for a clinical examination and bilateral wrist ultrasound. We measured plate-tendon distance, plate-tendon contact, sonographic changes in the FPL tendon, and postoperative radiographic parameters in the operatively treated wrist and the uninjured wrist.

RESULTS

Forty patients with Soong grade-1 or 2 plate prominence underwent bilateral wrist ultrasound examination; all of the patients had distal radial fracture fixation, 20 with the standard volar locking plate and 20 with the FPL volar locking plate. Similar proportions of patients with the FPL plate (65%) and those with the standard plate (79%) had plate-tendon contact (p = 0.48); however, the FPL volar locking plate group had significantly less of the FPL tendon in contact with the volar plate than the standard volar locking plate group at wrist extension at both 0° (p < 0.001) and 45° (p < 0.001). There was no difference (p = 0.5) in the proportion of patients with sonographic changes in the FPL tendon between the FPL volar locking plate group (25%) and the standard volar locking plate group (21%). The postoperative volar tilt was significantly lower in patients with FPL plate-tendon contact (p = 0.01) and correlated moderately with the percentage of FPL tendon-plate contact at 0° (r = -0.51; p < 0.001) and 45° (r = -0.53; p < 0.001). There were no cases of tendon rupture in the cohort.

CONCLUSIONS

We found that the FPL volar locking plate and increased volar tilt significantly reduced the plate-tendon contact area compared with the standard volar locking plate. In our asymptomatic cohort, we were unable to find a difference in sonographic changes in the FPL tendon. Further studies are needed to determine the clinical importance of decreased tendon-plate contact area seen in modified volar locking plate designs.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of Levels of Evidence.

Volar locking plates not touching the flexor pollicis longus tendon appear as prominences on radiographs: a cadaver study

Background

Plate protrusion is a risk factor for flexor pollicis longus (FPL) rupture following volar locking plate (VLP) surgery. However, plate prominence on follow-up radiographs is common. We hypothesised that a VLP that does not touch the FPL tendon can appear as a plate prominence projected over the volar ridge on lateral radiographs.

Materials and methods

We studied six current designs of widely used plates in formalin-fixed cadavers. Each plate was placed in six cadavers. We analysed 36 different plate–cadaver combinations. The main aim of plate fixation was to position the plate in the most distal position without FPL tendon contact. Radiographs were obtained using fluoroscopy. We evaluated plate prominence from the volar ridge according to the Soong grading system.

Results

Soong grades 0 (plate did not extend beyond volar ridge), 1 (plate protruded beyond volar ridge) and 2 (plate directly on or located beyond the volar ridge) were observed in 23 (63.9%), 9 (25.0%) and 4 (11.1%) cadavers, respectively. VariAx, DVR and VALCP showed grade 1 prominence, whereas Acu-Loc2, HYBRIX and MODE showed grade 2 prominence.

Conclusions

Implant protrusion was observed in 36% of plate–cadaver combinations, even if the plate did not touch the FPL. Estimating the risk of FPL rupture using lateral radiographs alone is likely insufficient. Our findings can be applied to accurately identify the presence of implant prominence following VLP surgery.

Anatomical-positional relationship between the bone structure of the distal radius and flexor pollicis longus tendon using ultrasonography

PURPOSE

In this study, using an ultrasonography, we investigated the positional relationship between the volar bone cortex of distal radius and flexor pollicis longus (FPL) tendon in the distal radius of healthy subjects.

METHODS

The subjects were 32 healthy volunteers (56 wrists) (Age 32.9 ± 8.5, 16 males and 16 females). Their wrists were imaged by an ultrasonography. The distances between the watershed line (WS) and FPL (A), between the distal margin of pronator quadratus (DMPQ) and FPL (B), between the FPL and volar radial bone cortex at the maximum muscle belly of the PQ muscle right below the sliding region of the FPL tendon (C), and between the WS and DMPQ (D) were measured.

RESULTS

All these parameters showed a normal distribution. When the correlation among the parameters was investigated, a correlation with an index of the physique, BMI, was noted in A (P < 0.01), B (P < 0.01), and C (P < 0.01), but no correlation was noted only in D (P = 0.59).

CONCLUSIONS

Our results were suggested that when distal radius fracture is treated with a distal plate placement, the appropriate placement can be achieved by applying about 3 mm additional dissection of soft tissue on the volar bone cortex distal to the DMPQ.