The Extended Flexor Carpi Radialis Approach for Distal Radius Fracture Fixation: A Prospective Study

Abstract

Purpose

The extended flexor carpi radialis (EFCR) approach for distal radius fractures and malunions was first described in 2001 by Orbay et al. This approach ensures optimal radial and dorsal exposure by releasing the radial septum and simplifies reduction by releasing deforming forces while providing access to the critical volar ulnar corner. We hypothesize the EFCR approach is safe and effective for routine use in the management of acute/subacute distal radius fractures without increased complication rates.

Methods

In total, 100 patients who underwent open reduction and internal fixation using an EFCR approach and a volar locking plate between 2018 and 2023 were included. A retrospective review of prospectively collected data was conducted including wrist range of motion, grip strength, Disabilities of Arm, Shoulder, and Hand scores, and complications. Volar tilt, radial inclination, ulnar variance and articular stepoff were measured after surgery. Descriptive statistics were used for analysis.

Results

The average follow-up period was 14 months with a mean Disabilities of Arm, Shoulder, and Hand score of 6.8 at the final visit. The mean wrist range of motion was 72° (±11) flexion, 60° (±11) extension, 78° (±8) supination, 77° (±6) pronation. The mean grip strength was 28 kg (±10). After surgery, the mean volar tilt was 7^o (±6), radial inclination 24^o (±4), and ulnar variance 0 mm (±1.6). Overall, the complication rate was 9%. There was one revision fixation for a periprosthetic fracture. Hardware removal was performed for plate-tendon irritation in 3% and patient preference in 2%. All other complications (3%) were minor and treated nonsurgically.

Conclusions

Our study supports the safety and effectiveness of the routine use of EFCR approach for acute/subacute operative distal radius fractures. It demonstrates excellent clinical, radiographic, and patient-reported outcomes. This series further supports its value in providing advantageous exposure and more efficient fracture reduction without increasing morbidity rates.

Type of study/level of evidence

Therapeutic IV.

The extended flexor carpi radialis (EFCR) approach for the treatment of distal radius fractures (DRFs) was first described in 2001 by Orbay et al,¹ alongside the introduction of the distal radius volar locking plate (VLP) for volar fixation. The latter allowed superior fixation of comminuted and dorsally unstable DRFs via distal locking screw mechanism, while circumventing the tendon complications prevalent in the dorsal approach.²

The EFCR approach was described to allow better exposure to the dorsal and radial aspects of the distal radius by releasing the radial septum and providing access to comminuted articular fragments via the intrafocal technique following pronation of the proximal fragment.¹ This allows for easier reduction, dorsal callus mobilization and bone grafting, and fixation of complex fractures from a volar approach.¹ In a 2012 follow-up study, Wijffels et al³ conducted a retrospective review of 35 patients with partially healed, malaligned DRFs treated using the EFCR approach. The study reported no instances in loss of reduction, deep infection, hardware failure, or tendon ruptures, with only one case of extensor tendon irritation caused by a dorsal prominent screw.³ Since then, EFCR has been demonstrated on cadaveric samples to offer the greatest average distal radius exposure (particularly when combined with carpal tunnel release), and to be safe and effective in additional studies ranging from 3 to 47 patient cases, with acute or acute-on-chronic DRFs.4, 5, 6, 7, 8 Moreover, a recent cadaveric study compared the EFCR approach to the traditional Henry approach, focusing on the distal extent of exposure, and found the former provided significantly better distal visualization of the volar distal radius (P < .05).⁹ The study highlights that the complete visualization of the critical volar ulnar corner with the EFCR approach may enhance the surgeon’s ability to detect and adequately address volar marginal fragments.

Despite the aforementioned studies on the EFCR approach, there remains a lack of robust clinical evidence in the literature supporting the approach’s safety and effectiveness for routine use because of small sample sizes and a lack of consistently collected patient-reported outcomes. As such, the aim of this study is to present a large series of acute/subacute DRF patients (n = 100) treated with open reduction and internal fixation (ORIF) via the EFCR approach and their short-term prospectively collected clinical, radiographic, and patient-reported outcomes. We hypothesize the EFCR approach is a safe and effective technique for routine use in the surgical management of DRFs with no increased rate of complications.

Materials and Methods

Participants

A retrospective review of prospectively collected data was conducted using institutional electronic medical records. One hundred patients who underwent a distal radius ORIF with a VLP using an EFCR approach between 2018 and 2023 were included. All surgeries were performed by a single fellowship-trained hand and upper-extremity surgeon. The EFCR approach was routinely used for all cases of distal radius ORIF amenable to a volar approach and standard VLP. Rare exceptions included cases treated by alternative surgical approaches, such as dorsal Barton fractures requiring dorsal approach, significant comminution necessitating a dorsal bridging plate, or an isolated lunate facet fracture for which a fragment specific fixation is used via a volar ulnar approach (N = 11). These cases have been excluded from our series. Inclusion criteria were as follows:

• •Acute or subacute (<6 weeks from injury) DRF, with or without intra-articular extension.
• •Isolated injury of the distal radius with no additional injuries of the ipsilateral upper extremity requiring surgery or immobilization.
• •Treated as an outpatient ambulatory day surgery procedure.
• •Minimum follow-up of 6 months.

This study was approved by the Univeristy Health Network institutional Research Ethics Board.

Outcome measures

Patient characteristics including age, biological sex, and affected hand were recorded. The time from injury to surgical treatment was also documented. Regular follow-up visits were conducted after surgery at 2 weeks, 6 weeks, 3 months, 6 months and 12 months. At each follow-up visit, the following clinical outcome measures in the affected limb were collected: active wrist flexion and extension, forearm pronation and supination as well as grip strength in kilograms. The Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire was administered at each time point to assess patient-reported outcomes.¹⁰ The preoperative wrist radiographs were collected using institutional electronic medical records and classified using the Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association Fracture and Dislocation Classification and the direction of instability.¹¹ For radiographic outcomes, volar tilt, radial inclination, ulnar variance, and articular stepoff were measured. Any complications reported in the chart during longitudinal follow-up were recorded.

Statistical analysis

Descriptive statistics, including the mean, median, standard deviation, minimum, and maximum values for each outcome measure, were calculated. Patient-reported functional outcomes, measured by DASH scores, were compared between the intra-articular and extra-articular fracture groups using an unpaired t test. As this study is mainly descriptive and no formal hypothesis testing was planned, a power analysis was not performed for this study. However, 100 patients was determined to be a sufficiently large series to add to contemporary literature and capture both common and infrequent complications (such as infection, nonunion, and complex regional pain syndrome) typically reported following distal radius ORIF.

Surgical technique

The surgical technique is detailed below and has been previously demonstrated by the authors in the 2021 American Academy of Orthopaedic Surgeons’ Orthopaedic Video Theater.¹²

A 7–10 cm volar incision is made along the flexor carpi radialis (FCR) tendon, extending distally to the proximal aspect of the distal pole of the scaphoid. Previous authors have employed a zig-zag incision for the wrist crease.^1,3 However, we prefer a straight incision that does not extend beyond the crease. By fully extending the exposure subcutaneously beyond the skin incision, we have found that adequate distal exposure can be achieved without crossing the wrist crease. The FCR tendon is then identified and its sheath is exposed along its length. The sheath is then incised superficially and the release is extended proximally and distally. The FCR tendon is then retracted ulnarly and the subsheath is inspected. The palmar cutaneous branch of the median nerve may be seen traveling closely to the ulnar aspect of the FCR subsheath or it may penetrate it.¹³ Although most branching patterns of the palmar cutaneous branch of the median nerve originate from the radial aspect of the median nerve proper, it has been shown that it can arise from the volar, dorsal, or ulnar aspects of the median nerve proper, and surgeons should be aware of this variability.¹⁴ As such, the subsheath is then released along the radial border with care taken to protect the palmar cutaneous branch. It is critical to release both the superficial and deep aspect of the FCR sheath widely in both proximal and distal directions in order to maximize visualization.⁴ Proximally, it can be released well into the forearm; distally, the release is extended around the distal pole of the scaphoid until the trapezial canal is reached. This release is performed well distal to the skin incision through careful subcutaneous dissection and release with tenotomy scissors; one must be cognizant of the proximity to the palmar cutaneous branch when performing this. The deep interval can then be exposed with the flexor pollicis longus retracted ulnarly. Parona space is then developed, and the carpal bursa is released. The pronator quadratus (PQ) is then fully exposed and the distal tendinous attachment is visualized to landmark the distal extent of the exposure. An inverted L-shaped release of the PQ is then completed, leaving a radial and distal cuff for later repair.

We then proceed to extend the FCR approach (Fig. 1), as described by Orbay et al,¹ by releasing the radial structures including the radial septum and brachioradialis (BR) tendon, subperiosteal release off the radius dorsally and radially, and pronation of the proximal metaphyseal segment. We start this by carefully identifying the BR tendon proximally at the distal radius metaphysis and separating it from the radial neurovascular bundle. This is extended across the radial styloid, exposing the fibro-osseous tunnel of the first extensor compartment. We then elevate the radial cuff of PQ as one sleeve in continuity with the radial septum and BR, eventually completely releasing the BR insertion and elevating the dorsal periosteum off the proximal fragment. We find that this sleeve is often robust enough to allow repair at the end of the case. The release of BR in continuity with the dorso-radial subperiosteal elevation is a variation compared to other authors who may prefer a midsubstance brachioradialis tenotomy to facilitate later repair. After this, the proximal radius can be pronated to further expose and mobilize the fracture, and intrafocal access to the distal articular block can be achieved. A combination of manual reduction, plate-assisted reduction and K-wires are used, as described by the primary surgeon.¹⁵ The vast majority of fractures were fixed with the Variable Angle Locking Compression Plate Distal Radius System (Depuy Synthes). Fixed Angle Locking Compression Plate Distal Radius System (Depuy Synthes) was used in some patients, particularly among early participants, before transitioning to Variable Angle plates. After completing the ORIF, the PQ is repaired over the VLP, re-establishing the periosteal sleeve and providing plate coverage to minimize tendon irritation. We subsequently routinely release the first extensor compartment tendons from their groove in the radial styloid to evacuate hematoma and minimize tenosynovitis and adhesions at the metaphyseal fracture site. We do not routinely release the carpal tunnel. Concomitant procedures, such as arthroscopy, were not performed in this series.

Figure 1.

Example of intraoperative exposure using the EFCR approach. A Completed dorsal-radial release. B Pronation of the proximal radius and intrafocal exposure. C Plate fixation.

Postoperative management

Patients were placed in a volar plaster below-elbow splint for 2 weeks after surgery. Following this, they were transitioned to a removable wrist splint to allow early range of motion exercises, and formal physical therapy was prescribed as needed. Regular follow-up visits were conducted after surgery at 2 weeks, 6 weeks, 3 months, 6 months, and 12 months.

Results

A total of 100 patients who underwent DRF ORIF between 2018 and 2023 were included in the study. The baseline patients’ characteristics are outlined in Table 1.

Table 1.

ROM, Grip Strength, and Radiographic Clinical Outcomes

Baseline Data
Number of patients	100
Age (mean, SD)	53 ± 16
Sex (female %)	68
Fractured side (right %)	37
Direction of displacement (dorsal %)	68
AO fracture type (%)	Type A: 16 Type B: 16 Type C: 68
ROM (o) At Final Follow-Up
Wrist flexion	72 ± 11
Wrist extension	60 ± 11
Supination	78 ± 8
Pronation	77 ± 6
Grip strength (kg)	28 ± 10
Postoperative Radiographic Measurements (o)
Ulnar variance	0.2 ± 1.6
Radial inclination	23.8 ± 3.8
Volar tilt	7.1 ± 6.1

AO, Arbeitsgemeinschaft für Osteosynthesefragen; ROM, range of motion.

Clinical outcomes

The average DASH score at 6 months was 12 (±13), whereas the average score at final follow-up was 6.8 (±8.8). Wrist and forearm range of motion and grip strength are outlined in Table 1. There was no statistically significant difference in DASH scores between the extra-articular and the intra-articular fracture groups (P = .99, Table 2).

Table 2.

Comparison of DASH Score Outcomes in Extra-Articular Versus Intra-Articular Fractures

DASH Score	Extra-Articular (Type A) N = 16	Intra-Articular (Type B/C) N = 84	Mean Difference	P Value
6 wk	29 ± 10	37 ± 21	8	.3634
3 mo	15 ± 10	19 ± 14	4	.402
6 mo	10 ± 8	14 ± 14	4	.4495
12 mo	9 ± 11	6 ± 8	3	.354

Radiographic evaluation

Preoperative Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association classification and direction of displacement as well as postoperative radiographic measurement at the final assessment are outlined in Table 1. An average minimal residual articular stepoff of 1 mm (±0.1) was noted in five patients based on final postoperative wrist radiographs.

Complications

The total complication rate in this study was 9% (n = 9). Complications requiring surgical interventions were seen in 6%, whereas the remaining 3% were minor and treated nonsurgically.

Reoperations

Excluding elective hardware removal, the reoperation rate in this series was 1% (n = 1). This case involved a revision fixation for a proximal periprosthetic fracture that occurred 11 months after the initial surgery, secondary to trauma from a fall. The original fracture had fully consolidated prior to the new injury.

Hardware removal

Three patients had hardware removal for pain symptoms secondary to suspected tendon irritation (3%) based on clinical examination. Additionally, two patients preferred to have hardware removal after reporting occasional discomfort or seasonal cold intolerance without signs of plate-tendon irritation on clinical examination (2%).

Other complications

There were two additional cases (2%) of transient tenosynovitis on clinical examination, both of which were resolved by the final follow-up without intervention. The involved tendon was the extensor pollicis longus in one case and the extensor carpi ulnaris in the other case. There was one case (1%) of asymptomatic delayed union for which a low intensity pulsed ultrasound machine was used. This patient eventually showed full radiographic union by the 1-year postoperative mark. There was one case of delayed onset mild carpal tunnel syndrome (CTS) treated nonsurgically, which occurred 6 months after the distal radius (DR) hardware removal procedure and 2.5 years after DR ORIF. There were no cases of reoperation for CTS. There were no cases of nonunion, wound healing concerns, superficial or deep infection, or tendon rupture.

Discussion

This study demonstrates that the EFCR approach is a safe and effective approach with minimal complications suitable for routine use in the fixation of acute and subacute DRFs. It significantly enhances access to the DR by providing improved visualization of the volar, radial, and dorsal aspects of the distal radius; allows for easier reduction of subacute fractures which require dorsal callus mobilization; and provides improved access to the volar ulnar corner. The wider exposure of the EFCR approach also allows the surgeon to have better control and mobilization of fracture fragments, reducing reliance on assistants for traction or adjunct percutaneous reduction maneuvers as release of contracture, callus, and deforming forces all facilitate a facile reduction. This greatly limits the need for forceful reduction maneuvers and retraction which may have negative consequences on skin, soft tissues, and neurovascular structures. Our experience is that this approach also allows the operating surgeon to perform cases independently or with a single assistant who does not require specialized surgical expertise. Lastly, this approach is based on the commonly used modified Henry approach to DRFs, which allows the technique to easily be learned and applied.^3,5, 6, 7

In a systematic review comparing operative and nonsurgical management of distal radius fractures, the reported DASH scores and range of motion for surgically treated DRFs were comparable to the results of our study.¹⁶ Our study further demonstrated that the EFCR approach also allows for excellent restoration of volar tilt, radial inclination, and ulnar variance (Fig. 2).

Figure 2.

Preoperative type C fracture radiographs. A Posterior anterior radiograph. B Lateral radiograph. Postoperative radiographs demonstrate restoration of volar tilt, radial inclination, and ulnar variance. C Posterior anterior radiograph. D Lateral radiograph.

Our results suggest that the increased soft tissue exposure with this approach is not associated with an increased rate of adverse events. In fact, our overall complication rate (9%) is lower than previously reported total complication rates in DR fixation (12% to 27%).17, 18, 19, 20, 21 Similarly, our total reoperation rate, including elective hardware removal, was lower at 6%, compared to a 6% to 11% reoperation rate reported in the literature.18, 19, 20, 21 The most significant complication in this study was a periprosthetic fracture, which required a revision ORIF. This complication is unlikely to be influenced by the type of approach, but can more so be attributed to a stress riser fracture secondary to retained hardware. The most common indication for reoperation in our series was for hardware removal which occurred in five out of six cases. Only three (3%) of these patients showed signs of plate-tendon irritation on clinical assessment. The remaining two cases (2%) were driven by patient preference for hardware removal. The rate of hardware removal in DRFs treated with VLP varies considerably in the literature. Complex and distal intra-articular fractures may require more distal placement of VLPs, which could lead to higher rates of hardware removal than typical cases.²² The mean reported average according to a systematic review by Yamamoto et al²³ was 9%, which decreases to 7% when routine hardware removals are excluded compared to a total of 5% hardware removal rate in our series. We believe that appropriate primary closure of the PQ with full plate coverage is key to minimizing hardware removal rates. In addition, we focus on positioning the plate proximal to the watershed line when possible and assessing for dorsal and distal radioulnar joint screw prominence using a carpal shoot-through view.²⁴ Additionally, concomitant release of the first extensor compartment as part of this exposure may reduce the risk of postoperative de Quervain tenosynovitis.²⁵ We believe these steps effectively minimize tendon-related complications and reduce the need for hardware removal.

We do not routinely perform prophylactic release of carpal tunnel along with DR ORIF. The incidence of CTS in our series was low compared to the reported 3–12% incidence following DR ORIF.^19,20,26 There was only one case of mild CTS managed nonsurgically, with onset of symptoms around 6 months following hardware removal surgery and 2.5 years from the ORIF procedure. Moreover, prophylactic release of the carpal tunnel has not been sufficiently supported by the literature.²⁷ Given the limited incidence of CTS in this series, one may hypothesize that performing the EFCR approach with release of the FCR as distal as possible to the level of the scaphoid tubercle may confer a protective effect by partial decompression of the carpal tunnel via the FCR sheath as described by Weber and Sanders;²⁸ however, conclusions regarding this is beyond the scope of the current study. Lastly, there was one case of asymptomatic delayed union in our series. This patient did not require further surgical intervention as there was adequate healing by the one-year postoperative mark. The ulnar based intraosseous blood supply to the DR metaphysis, which is considered essential for healing, should remain undisrupted in this approach.²⁹

The most common fracture pattern in our series was intra-articular (Arbeitsgemeinschaft für Osteosynthesefragen type C, 68%), and with dorsal displacement (68%). It may be anticipated that intra-articular fracture patterns would potentially be associated with lower functional and radiographic outcomes; however, we did not find statistically significant differences in DASH scores when comparing the extra-articular and intra-articular groups. Wadsten et al³⁰ similarly found no difference in QuickDASH (Disabilities of the Arm, Shoulder, and Hand) scores in their prospective multicenter study comparing the effects of intra-articular involvement on the clinical outcomes in DRFs. The retrospective analysis by Souer et al³¹ comparing simple intra-articular fractures to extra-articular fractures treated with VLP also demonstrated no significant clinical differences between the groups at the 2-year follow-up duration, including DASH scores.

To account for intersurgeon variability in the implementation of the EFCR approach, our patient cases included operations that were performed consistently by a single surgeon. This allowed for standardization of the surgical technique performed and minimized operative confounders.

Limitations

Our study has several limitations. First, it does not include a control group and there was no routine assessment of the uninjured side for comparison. Given this, results of the study may lack a benchmark and be limited in its ability to help isolate a specific aspect of the EFCR contributing to long-term patient outcomes. There, however, are certainly numerous studies describing outcomes of patients undergoing volar plating for DRFs through a traditional approach including multiple systematic reviews which serves as a reasonable comparison. Secondly, this study involves non-randomized patient cases from a single tertiary care institution. A larger prospective multicenter cohort study could further support our findings. Lastly, we present short-term results of our patient series with an average follow-up of 14 months. Further follow-up could certainly strengthen the conclusion that the EFCR approach does not affect longer term outcomes.

Despite its limitations, the current study adds valuable insight to the existing literature, which is hindered by small sample sizes, narrow surgical indications, and a lack of prospectively collected data and patient-reported outcome measures. It demonstrates that, despite the increased surgical exposure and soft tissue releases, the EFCR approach can be safely implemented for routine use in DR ORIF, with prospectively collected data showing comparable or superior clinical, radiographic, and patient-reported outcome measure outcomes without an increase in complication rates. These findings offer valuable guidance for surgeons considering this technique on a routine or case-by-case basis. Ultimately, the EFCR approach represents a powerful addition to the surgeon’s armamentarium in the management of DRFs.

Conflicts of Interest

No benefits in any form have been received or will be received related directly to this article.