Distal Radius Volar Plate Design and Volar Prominence to the Watershed Line in Clinical Practice: Comparison of Soong Grading of 2 Common Plates in 400 Patients

Flexor Tendon Attritional Ruptures Following Distal Radius Volar Plate Fixation

PURPOSE

To investigate patient and radiographic factors that may correlate with the time to flexor tendon rupture following volar plate fixation of distal radius fractures.

METHODS

A total of 31 patients who underwent volar plate removal because of flexor tendon rupture were analyzed. Patient demographics and the interval from operative fixation until rupture were determined retrospectively. Volar tilt and lateral carpal alignment were measured radiographically. The Soong classification was used to grade volar plate prominence. The correlation between the duration to tendon rupture and volar tilt, carpal alignment, and age was evaluated.

RESULTS

There were 7 men and 24 women. Mean age at the time of hardware removal and flexor tendon management was 66 years (n = 31). Radiographs were classified as Soong 1 (n = 24) and Soong 2 (n = 3). The mean measured volar tilt was -4° (range, -20°-+7°). The mean interval from operative fixation until complete tendon rupture was 4.9 years, (range, 0.3-13.1 years; n = 30). There was no correlation between the time interval to rupture and the magnitude of tilt, carpal alignment, or age at the time of operative fixation.

CONCLUSIONS

Although volar plate prominence was present in all patients with flexor tendon ruptures, radiographic parameters including the degree of dorsal tilt, lateral carpal alignment, and patient age did not correlate with the time interval from fixation to tendon rupture.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Study of the position of six volar locking plates for distal radius fracture relative to the watershed line

INTRODUCTION

Volar plate malpositioning in the treatment of distal radial fracture can lead to tendinitis or even tendon tear, especially when the plate position is very distal. We studied the impact of design on plate position in the distal radius. The primary aim was to compare the position of six volar wrist plates relative to the watershed line using the Soong classification. The secondary objectives were to assess the epidemiology of volar locking plate fixation within the administrative Département of Finistère (northwestern France) and to study whether the type of fracture played a role in plate position.

HYPOTHESIS

The plate design itself influences positioning relative to the watershed line on the Soong classification.

MATERIALS AND METHODS

A total of 2723 volar locking plate fixation cases were analyzed and categorized according to the Soong classification. Plates used were divided into six groups based on design: Zimmer Biomet®, Newclip Technics®, Stryker®, Synthes®, Medartis® and Medartis® Footprint. The number of Soong 0 + 1 plates (i.e., plates graded 0 and 1 taken together) was determined for each design, then compared using the Marascuilo procedure with a significance level of α = 0.05.

RESULTS

On the Marascuilo procedure, we found significant differences in the number of Soong grade 0 + 1 plates. The Zimmer Biomet and Newclip Technics® plates were significantly more often proximal to the watershed line than the Synthes and Medartis Footprint plates. Plate position with the Medartis® design was significantly more proximal to the watershed line than for its companion design, the Medartis® Footprint plate. The rate of volar locking plate fixation of distal radial fractures over the past 10 years increased in Finistère. Also, the type of fracture affected the choice of plate when different designs were available within a hospital center (Medartis® Footprint plate used in 2R3A fractures).

CONCLUSION

Our study highlights a significant difference in volar locking plate position relative to the watershed line between the various models available. Plate design is a deciding factor when treating distal radial fracture, to avoid impingement when implant removal is not routinely planned.

LEVEL OF EVIDENCE: 3

Higher Soong grade predicts flexor tendon issues after volar plating of distal radius fractures - a retrospective cohort study

BACKGROUND AND PURPOSE

Soong classification is used to estimate volar locking plate prominence and evaluate the risk for flexor tendon ruptures after surgical treatment of distal radius fractures (DRFs). However, the scientific community has questioned the Soong classification due to lacking evidence. Therefore, this study aimed to evaluate the accuracy of Soong grading as a predictor for flexor tendon issues and plate removal.

PATIENTS AND METHODS

We performed a retrospective single-center review of adult distal radius fracture patients treated with a volar locking plate between 2009 and 2019. In total, 2779 patients were included in the study. The primary outcome was a flexor tendon issue (flexor tendon rupture, tendinitis, or flexor irritation), whereas plate removal was a secondary outcome. Using Soong grade 0 as a reference, we used univariable and multivariable logistic regression to calculate odds ratios (OR) with 95% confidence intervals (CI) for flexor tendon issues and plate removal.

RESULTS

In total, 756 (27%) patients were graded as Soong 0, 1679 (60%) Soong 1, and 344 (12%) Soong 2, respectively. There were 32 (1.2%) patients with flexor tendon issues, of which 4 were flexor tendon ruptures, 8 tendinitises, and 20 flexor irritations. The adjusted OR for flexor tendon issues was 4.4 (CI 1.1-39.7) for Soong grade 1 and 9.7 (CI 2.2-91.1) for Soong grade 2. The plate was removed from 167 (6.0%) patients. Soong grade 1 had a univariable OR of 1.8 (CI 1.2-2.8) for plate removal, and Soong grade 2 had an OR of 3.5. (CI 2.1-5.8), respectively.

CONCLUSION

Flexor tendon ruptures are rare complications after the volar plating of DRFs. A higher Soong grade is a risk factor for flexor tendon issues and plate removal.

TRIAL REGISTRATION

The trial was retrospectively registered.

Using Trident distal radial locking plate to fix the fracture of distal radius volar rim

BACKGROUND

The volar locking plates have been widely used in a variety of distal radius fractures, but they still have several limitations when dealing with small fragments located around the watershed line with widely reported complications. The volar rim fragments play a critical role in radiocarpal joint stability and failing to secure the volar rim fragment usually results in carpal instability, subluxation, or even dislocation. This study investigates clinical outcomes in the use of a novel implant, the Trident distal radial (TDR) locking plate to treat distal radius fracture with the intermedium column edge (lunate fossa volar rim) fragment involvement.

METHODS

A retrospective study of 25 patients was conducted, all patients had intermedium column fractures with lunate fossa volar rim involvement and treat with the TDR between January 2016 and December 2019. The clinical assessment outcomes included VAS Pain, PRWE, and DASH scores. Objective measurements included ROM of the injured wrist and grip strength. Final radiographs were used to evaluate radial inclination, volar tilt, ulnar variance, and distal radioulnar joint instability. Secondary operations related to hardware complications were also recorded.

RESULTS

The outcome revealed that the mean VAS Pain Score was 1.3, mean DASH score was 10.5, and mean PRWE score was 9.3. Objective measurements revealed good ROM recovery and an 89% gripping strength recovery compared with contralateral hand. Radiographic measurements revealed good maintenance of volar tilt, radial inclination, and mean ulnar variance. There were no complications related to the implant and all fracture sites were union.

CONCLUSION

We believe that the TDR provided more stable fixation among distal radial fractures that predominantly involved the intermedial column and volar rim fragment, and allowing early rehabilitation. We could obtain excellent results in the wrist ROM, gripping power, and Pain Score (VAS).

The Impact of the Soong Index on Hardware Removal and Overall Reoperation Rates After Volar Locking Plate Fixation of Distal Radius Fractures

PURPOSE

This study sought to determine the impact of volar plate prominence on reoperation rates after open reduction and internal fixation of distal radius fractures with volar locking plates and to identify other factors associated with removal of hardware (ROH) or a reoperation.

METHODS

A retrospective study of patients who underwent distal radius open reduction and internal fixation between 2012 and 2016 at 2 level I trauma centers was conducted. Plate prominence was evaluated using the Soong index at the first postoperative visit. The details of patient demographics, fracture and plate characteristics, complications, and reoperations were recorded. Bivariate and multivariable regression analyses were used to identify factors associated with increased rates of ROH and overall reoperation.

RESULTS

A total of 732 (70.2%) of 1,042 patients completed follow-up at an average of 38.2 months, including 34 patients with bilateral operations, yielding 766 distal radius fractures. One hundred sixteen (15.1%) patients underwent reoperation at an average of 12.1 ± 13.6 months after the index surgery. Removal of hardware was the most commonly performed reoperation (77 patients, 10%). The multivariable regression analysis revealed significantly higher rates of ROH in Soong grade 1 or 2 patients (odds ratio 16, 95% CI 5.8-47; odds ratio 44, 95% CI 14-140, respectively) than in Soong grade 0 patients. Plate type, younger age, bilateral injuries, and concomitant procedures at the time of the index operation were all associated with increased risk of ROH. There were significant differences between individual surgeons the in rates of ROH (range 2.1%-22%) and overall reoperation (range 5.2%-36%). Compared with other hand surgeons, fellowship-trained hand surgeons had lower rates of ROH (8% vs 14%, respectively) and overall reoperation (12% vs 22%, respectively).

CONCLUSIONS

The rates of ROH and overall reoperation increase with increasing Soong grade. Plate type is independently predictive of future ROH. Older patients and those undergoing open reduction and internal fixation experience lower rates of subsequent reoperation.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Comparison of the Orientation Angles of Volar Locking Plate Distal Ulnar Locking Screw for Distal Radius Fractures

PURPOSE

This study aimed to measure the angles between the screw and plate in 16 commercially available volar locking plates (VLPs) to determine the fixable intra-articular fragment size.

METHODS

Ulnar orientation angles (axial plane) and elevation angles (sagittal plane) between the distal ulnar screw and plate were measured for 14 fixed-angle VLPs and 2 variable-angle VLPs. Each VLP was simulated by 2 surgeons to sit distally and ulnarly in 10 normal distal radius models. The distance between the screw and distal/ulnar end of the distal radius on both the volar and dorsal sides, designated as the longitudinal/lateral distance, was measured to identify the fixable size of the 2 intra-articular fragments: volar lunate fragment and dorsoulnar fragment. Relationships between the ulnar orientation angle and dorsal-side lateral length as well as the elevation angle and dorsal-side longitudinal distance were analyzed.

RESULTS

The ulnar orientation and elevation angles ranged from 6.5° to 16.9° and -5.8° to 34.3°, respectively, for fixed-angle VLPs and -12.5° to 32.2° and 3.1° to 42.1°, respectively, for variable-angle VLPs. The minimal longitudinal distances on the volar side with the fixed- and variable-angle VLPs were 4.3-10.9 mm and 5.8-5.9 mm, respectively. On the dorsal side, the lateral distance negatively correlated with the ulnar orientation angle (R = -0.74), and the longitudinal distance negatively correlated with the elevation angle (R = -0.89).

CONCLUSIONS

The Depuy Synthes variable-angle VLP provides an advantage for fixating small intra-articular fragments. For fixed-angle VLPs, the Mizuho VLP provides an advantage for fixating small volar lunate fragments. A narrow dorsoulnar fragment can be fixated using a plate with a large ulnar orientation angle, such as the Zimmer Biomet or Mizuho VLP.

CLINICAL RELEVANCE

The ability of each individual commercially available plate to capture specific intra-articular fragments should be known.

Functional outcomes following fixation of a marginal distal radius fracture with two commonly used volar locking plates: a retrospective cohort study

Introduction

The volar locking plate has been widely used for unstable distal radius fractures to provide early recovery of wrist function. Volar plate prominence to the watershed line has been reported to be related to flexor tendon irritation, and avoid implant prominence in this area was suggested. On the other hand, marginal distal radius fracture patterns required the plate to cross the watershed line, making conflict over plate positioning on marginal distal radius fractures. This study compared functional outcomes in patients with marginal distal radius fractures treated with two different implants.

Materials and methods

A retrospective study was conducted, all patients who received a Synthes 2.4 mm LCP or an Acumed Acu-Loc VLP between January 2015 and December 2018 were reviewed. The marginal distal radius fracture pattern was the most distal horizontal fracture line within 10 mm of the lunate fossa’s joint line. The primary outcomes including patient-reported pain scores, range of motion, and grip strength were assessed. Secondary outcomes included patient-based subjective satisfaction scores of the injured wrist and hand function. The Mayo Wrist Score and the requirement for a secondary procedure related to hardware complications were also recorded.

Results

Forty-two patients met our inclusion criteria. Twenty-one patients were treated with the Synthes 2.4 mm LCP, and 21 patients with the Acumed Acu-Loc VLP. The primary outcome revealed that post-operative range of motion (P = 0.016) and grip strengths (P = 0.014) were significantly improved in the Acu-Loc VLP group. The MAYO wrist score in the Acu-Loc VLP group was also significantly better (P = 0.006).

Conclusions

Despite advances in implant designs, flexor tendon irritation or rupture is still a complication following distal radius’s volar plating. We believe the Acumed Acu-Loc VLP design provided better functional outcomes than the Synthes 2.4 mm LCP if appropriately and carefully placed into its designed-for position. This positioning results in promising patient satisfaction when treating marginal distal radius fractures.

ANATOMICAL STUDY OF VOLAR FACE OF DISTAL RADIUS AND COMPARISON WITH THE SHAPE OF LOCKING VOLAR PLATES

ABSTRACT Objective: To evaluate the volar cortical angle (VCA), the variation in lateral and intermediate columns, the shape and pattern of the watershed line (WL) of the distal radius and its correlation with locking volar plates available. Methods: 27 human cadaveric radial bones of the Department of Morphology and nine locking volar plates of six different companies were analyzed. VCA were measured from lateral and intermediate columns and their corresponding values on plates, as well as comparing the relief of radius and plates. In the WL analysis, we compared the standard format found on the radius and its equivalent on plates and divided into four types: biconvex, convex, ulnar convex and plan. Results: VCA varied between columns of the distal radius extremity. The mean in the lateral column was 153.40 degrees and 146.06 degrees in the intermediate. Four of nine plates showed no variation in volar angulation. From 27 distal radius, 13 showed convex pattern and 12 had biconvex, whereas most plates (seven of the nine analyzed) were biconvex drawing. Conclusion: Radial bone anatomy was variable. The intermediate column was, on average, steeper than lateral column. Synthes®-2 plate presented the closest design to the anatomy of the distal end of the radial bone, followed by Newclip®-2 plate. Level of Evidence II, Anatomic and Descriptive Study.

[Fractures of the Distal Radius]

The fracture of the distal radius is the most common human fracture. The optimal management of this injury requires extensive knowledge and skills regarding closed and open reposition maneuvers, plastering and various surgical osteosynthesis techniques. Typical as well as rare accompanying injuries must be recognized and included in the treatment regimen.

Impact of Soong grading on flexor tendon ruptures following palmar plating for distal radial fractures

The purpose of this study was to evaluate flexor tendon injuries following palmar plating of distal radial fractures relative to the Soong grade. This retrospective cohort study included 113 patients who underwent palmar plate removal after a distal radial fracture between 2010 and 2016. In 13 patients, a greater than 50% injury of the flexor pollicis longus tendon was observed. Of these, nine patients were classified as Soong grade 2, four as Soong grade 1 and none as grade 0. The difference between the Soong groups was statistically significant (p = 0.006). Flexor tenosynovitis was present in eight patients (7%) and more likely in patients with a higher Soong grade (p = 0.026). We conclude that higher Soong grades are associated with significantly more flexor tendon complications. Therefore, elective removal of the palmar plate after union of the fracture should be considered in patients with Soong grades 1 and 2. Level of evidence: IV.