Three Column Fixation Through a Single Incision in Distal Radius Fractures

Abstract

Purpose  The purpose of this study was to evaluate the clinical and functional results of 67 patients with distal radius fracture (DRF), treated with a modified surgical technique that allows three-column fixation through the same palmar approach.

Patients and Methods  Between 2014 and 2019, we treated 67 patients using a particular surgical technique. All patients suffered DRF, classified using the universal classification system. Two different intervals were developed palmary: the first ulnarly to the flexor carpi radialis tendon for direct visualization of the distal radius and the second one radially to the radial artery for direct visualization of the styloid process. An anatomic volar locking compression plate was applied to all patients. The radial styloid process was fixed and stabilized either with Kirschner-wires or an anatomic plate through the same incision. Functional results were evaluated based on the Disabilities of the Arm, Shoulder and Hand and Mayo wrist scores. Range of motion and grip strength of the injured wrist were statistically compared with the opposite side.

Results  The mean follow-up was 47 months (13–84). All fractures were united, and all patients recovered to the preinjury level of activity. The mean flexion–extension range was 73.8° to 55.2° and the supination–pronation range 82.8° to 67°. No infection or nonunion occurred. No major complications were reported.

Conclusion  Open reduction and internal fixation, under specific indications, is the best treatment option in DRF. The described technique provides excellent visualization to the distal radius surfaces and allows the internal fixation of the radial columns through the same skin incision. Therefore, it can constitute an efficient choice in the treatment armamentarium of DRF.

Distal radius fractures (DRF) are the most common orthopedic injury, accounting the 17,5% of all fractures in adults. They may result from of a low energy mechanism in elderly people or high energy mechanisms in the younger population. Low energy fractures are often extra-articular and should be managed with closed reduction and casting. On the other hand, half of the distal radius fractures are considered intraarticular and result from high-energy trauma. ¹

Articular incongruity and comminution result in wrist instability and distal radius malunion. These are commonly associated with wrist pain, limited range of motion (ROM), and strength. Open reduction and internal fixation (ORIF) provide the best articular surface restoration and wrist stabilization and could be the treatment of choice for this kind of injury. Conservative treatment, closed reduction, and external fixation or percutaneous pinning are other treatment options that have been proposed. However, most research works indicate that ORIF has superior results when compared with other surgical methods. ^{2 3 4}

The anatomic restorations of the radial column, the articular surface, and the distal radioulnar joint (DRUJ) are the three keys to deal with distal radius fractures (DRF). Three kinds of approaches offer access to these structures: the palmar approaches, which include the modified Henry and the trans-flexor carpi radialis (FCR) approach, the dorsal approach between the extensor compartments, and the direct approach to the radial styloid. ⁵ Palmar approaches provide excellent exposure of the distal radius palmar surface. They also allow the limited approach to radial styloid and brachioradialis insertion, which can be safely detached from the radius. ⁶ However, the ulnar side of the radius palmar surface is poorly approached, and DRUJ is difficult to be evaluated. ⁷ When a combined approach of ulnar and radial to FCR tendon is chosen, special attention should be given not to damage the palmar branch of the median nerve, which lies directly lateral to the tendon. ⁸ Also, plating the radial styloid through a palmar approach is difficult as there is no direct visualization. In cases where the radial column must be fixed, an additional approach is demanded, which uses the interval between the first and then second extensor compartment. This exposure allows the anatomic reduction and buttress plating of the radial styloid. The dorsal approach to the wrist is used by many surgeons to fix a DRF. ⁹ It uses multiple intervals between extensor compartments and allows good exposure of the distal dorsal radius surface. ¹⁰ Tendon rupture is a common complication and second surgery for implant removal is usually necessary. ^{11 12}

Many times, more than just one column needs to be fixed and more than one approach should be performed. We propose an approach to inspect and fix more than one column through a single incision. By creating different intervals through the same palmar incision, we are able to deal with most DRF.

Surgical Technique

Under general anesthesia or axillary block, the patient is positioned supine and the limb is placed on a surgical table. We perform a straight palmar incision over the FCR starting 5 cm proximal to the waistline ( Fig. 1 ). Extending the incision in a curved way toward the thumb for 1 cm helps the skin flaps to be mobilized easily. In most cases, FCR is palpable under the skin, but in cases of significant edema or obese patients, the scaphoid tubercle can be used as a landmark. After recognizing the radial artery and FCR, the tendon's sheath is opened and the tendon is retracted radially ( Fig. 2 ). The superficial muscle fascia is incised just ulnarly to FCR. FPL and median nerve are recognized, and care must be taken not to injure the palmar cutaneous branch. These structures are retracted ulnarly, and the pronator quadratus is identified just above ( Fig. 3 ). The muscle is incised in a typical way from its insertion to the radius and moved away from the radius surface. It is critical to expose the whole radius surface until its ulnar edge. Fracture sides are cleaned and primary mobilized.

Fig. 1.

A straight palmar incision is performed over the FCR starting 5 cm proximal to the waistline. The scaphoid tubercle can be used as a landmark (1). FCR, flexor carpi radialis.

Fig. 2.

After recognizing the FCR (1) and the radial artery (2), the tendon's sheath is opened, and the tendon is retracted radially. FCR, flexor carpi radialis.

Fig. 3.

The superficial muscle fascia is incised just ulnarly to FCR (1). FPL and median nerve are recognized and retracted ulnarly ( black arrow ). The pronator quadratus (2) is identified just above. FCR, flexor carpi radialis; FPL, flexor pollicis longus.

After finishing this “main” approach, we remove all instruments, and through the same incision, we perform a radial styloid approach. The recognized radial artery is retracted ulnarly, and dissection is carried down to the first extensor compartment. Great care must be taken not to injure the radial sensory branches, which must be recognized and retracted dorsally. The first compartment is incised; abductor pollicis longus and extensor pollicis brevis are mobilized and retracted dorsally as well ( Fig. 4 ). Brachioradialis insertion is recognized and detached with the knife at the proximal and palmar edge of the pulley. At this point, the whole radial styloid process is exposed and fully viewed ( Fig. 5 ). Fragments are mobilized, and reduction is achieved as far as brachioradialis is fully detached. If the fracture is not comminuted, the radial styloid is reduced and stabilized with one 1.5 mm Kirschner wire (K-wire). In the presence of comminution, the reduction is kept in place using an anatomical radial styloid plate.

Fig. 4.

After finishing the “main” approach, radial styloid is approached through the same incision. The recognized radial artery (1) is retracted ulnarly, and dissection is carried down to the first extensor compartment. The first compartment is incised. Abductor Pollicis longus (2) and extensor pollicis brevis (3) are mobilized and retracted dorsally ( black arrow ).

Fig. 5.

At the proximal and palmar edge of the pulley, brachioradialis insertion (1) is recognized and detached with the knife. The whole radial styloid process (2) is exposed and fully viewed.

With the radial column fixed and stabilized, we return to the first surgical plane. Anatomic reduction of radiocarpal (scaphoid and lunate fossa) and radioulnar joint (sigmoid notch) surfaces is achieved. Previous brachioradialis tenotomy and radial length restoration by fixing the styloid process make the anatomic reduction of these intra-articular fragments easier. The reduction is stabilized by placing an anatomic plate ( Fig. 6 ). The plate must be positioned as ulnar as possible to ensure that the volar lunate corner and the sigmoid notch reduction are well buttressed and secured ( Fig. 7 and 8 ). After finishing the fixation, the DRUJ stability is tested using the Ballottement test. The wound is closed, and a volar cast is used to immobilize the wrist, leaving metacarpophalangeal joints free to allow finger exercises from the first postoperative day. The cast is removed after 15 days, and patients start passive and active wrist exercises. ¹³

Fig. 6.

The reduction is stabilized by placing an anatomic plate (1). The approach allows full visualization of the distal radius palmar surface and the radial styloid (2).

Fig. 7.

The plate must be positioned as ulnar as possible to make sure that the volar lunate corner and the sigmoid notch reduction are well buttressed and secured.

Fig. 8.

In the presence of comminution, the reduction of the radial styloid is kept in place using an anatomical plate.

Materials and Methods

Sixty-seven patients were treated using the described surgical technique from 2014 until 2019. The patients' mean age was 48 years old (19–62). All fractures were classified using the universal classification system proposed by Rayhack ¹⁴ and later refined by Cooney in 1993. ¹⁵ As no classification system seemed to provide adequate information about the fracture or the treatment option, ¹⁶ we chose this simple classification separating injuries in intra- and extra-articular fractures and displaced nondisplaced fractures. Plain X-rays and computerized tomography (CT) scans in 31 of the cases were used for the fracture classification and the preoperative planning. ¹⁷ Of 67 patients, 12 had a displaced irreducible extra-articular fracture (IIb) and 55 had a displaced intra-articular fracture (IVb, IVc). In 35 patients, the distal ulna was intact, and in 32 patients, there was a fracture either of the distal ulna (2) or of the ulna styloid process (30).

All patients were treated using an anatomic volar plate. In all cases, one K-wire was used for provisional stabilization of the radial styloid through the described second interval and before placing the volar plate. In 27 patients, the K-wire was replaced by an anatomic radial styloid plate, in 23 patients, the K-wire remained and was removed 1 month after the surgery, and in 17 patients, it was removed after placing the volar plate. In two patients, additional fixation of the ulna with a plate was performed. DRUJ was stable in 63 cases and unstable in 4 cases, where a K-wire was used for stabilization and was removed after 6 weeks. In two cases, a palmar-specific fixation was used, additionally to the plate, to deal with a lunate facet fracture.

Anteroposterior and lateral radiographs of the operated wrist were obtained for all cases on the first postoperative day. Follow-up was arranged at 2, 6, 12, and 24 weeks and 12 and 24 months and included radiological and clinical investigation. All cases were also evaluated for superficial or deep infection around the surgical site, considering wound leaking, redness, and swelling. Follow-up X-rays were taken at 4, 8, and 12 weeks and at 12 months to determine any extra-articular deformity (radial length and dorsal tilt), intra-articular step-off, and posttraumatic arthritis according to the classification proposed by Kirk and Jupiter. ¹⁸

Clinical evaluation was performed, measuring the grip strength, flexion, extension, supination, and pronation in both wrists. Functional results were evaluated based on the Disabilities of the Arm, Shoulder and Hand (DASH) ¹⁹ score and Modified Mayo Wrist Score. ²⁰ ROM and grip strength of the injured wrist were statistically compared with the opposite side, and the value of p  < 0.005 was considered to be statistical significant.

Results

The follow-up duration was 47 months (13–84). The mean flexion range was 73.8° (60–85), the mean extension range was 55.2° (45–70), the mean supination range was 82.16° (70–90), and the mean pronation range was 67.01° (55–75). The mean grip strength was 39.6N (30–56). The mean MAYO wrist score was 95.45, and the mean DASH score was 0.67.

The statistical analysis that was conducted in our cohort (67 patients) displayed no significant difference ( p  > 0.05) for all the parameters that were evaluated between the fractured and the contralateral wrist ( Table1 ).

Table 1. Functional outcomes: comparison between fractured and uninjured wrist.

	Fractured wrist			Uninjured wrist			p -Value
	Min	Mean	Max	Min	Mean	Max
Flexion a	60	70.8	85	65	77.6	85	>0.05
Extension a	45	55.2	70	50	57.6	70	>0.05
Supination a	70	82.2	90	75	84.2	90	>0.05
Pronation a	55	67	75	60	68.8	80	>0.05
Grip strength b	30	39.6	56	31	41.4	58	>0.05
MAYO score	80	95.5	100	100	100	100	>0.05
DASH score	7.5	0.67	0	0	0	0	>0.05

Abbreviation: DASH, Disabilities of the Arm, Shoulder and Hand.

^aFlexion, extension, supination, and pronation are measured in SI units (degrees).

^bGrip strength is measured in SI units (Newton [N]).

With regard to the first postoperative day X-rays, 50 patients presented an anatomical reduction and 17 presented an articular step less than 2 mm. In all cases, the radial length was measured within 2 mm of the radial height of the contralateral wrist in the anterior–posterior radiograph. Fifty-six patients presented no wrist arthritis (grade 0), and 11 presented slight joint space narrowing (grade 1).

All fractures united, and no major complications were reported. One patient suffered a minimal secondary displacement of the radial styloid fixation after the K-wire extraction. This resulted in a 1 mm step off in the articular surface of the radial column, even though the patient remained asymptomatic. All other fixations remained radiographically unchanged throughout the follow-up period compared with the immediate postoperative X-rays. No infection was noted.

Regarding minor complications, one patient was diagnosed with complex regional pain syndrome in the first month after surgery and was treated with physiotherapy. The patient recovered at 4 months. Three patients mentioned a postoperative hyperesthesia along the radial cutaneous nerve area of sensation, but they were all free of symptoms at 6 months.

Discussion

The surgical treatment of DRF is a matter of discussion. There are many factors, such as age, occupation, bone, and host quality, to be considered. In a recent systematic review, He et al found no significant differences in functional outcomes between the surgical and nonsurgical treatments other than the radial inclination and the wrist flexion, which were found significantly superior in the surgical groups. ²¹ Arora et al found no significant differences between palmar fixation and conservative treatment of DRF in patients over 65 years old. ²² In fracture-related variables, a dorsal angulation >15°, radial shortening >3 mm, intra-articular step-off >2 mm, and high risk of redisplacement ²³ seems to be the main criteria in favor of surgical treatment. ²⁴

Choosing between dorsal and volar approaches is a field of conflict. Comparing functional results and complication rates indicates no significant differences between palmar and dorsal fixation in multiple studies. ^{12 25 26 27} However, many studies indicate that a palmar approach can deal with most of DRF ^{24 28 29} and the dorsal approach is crucial to deal with specific fracture patterns. ²⁹ The fracture pattern and the adequate visualization to restore wrist biomechanics should be the critical parameters in decision-making.

The incidence of radial artery injury when performing the Henry approach in the distal radius is less than 1%. ³⁰ However, developing another interval just radially to the artery would increase that risk. Placing the main volar approach, ulnarly to the FCR, a soft issue “envelope” is made to protect the radial artery. On the contrary, iatrogenic injury of the median nerve and its palmar cutaneous branch is a common complication when performing an approach ulnarly to the FCR. ^{8 31} The recognition of these structures is crucial to avoid such a complication ^{31 32}

The most common concept that describes the biomechanics of the wrist and classifies injuries of the distal radius is the concept of three columns described in 1996 by Rikli and Regazzoni. ³³ According to this model, a three-column biomechanical construction is formed by the distal radius and the distal ulna. The lateral column is the lateral radius with the scaphoid fossa and the styloid process and is the column responsible for radiocarpal stability. The intermediate column is the medial part of the distal radius, with the lunate fossa and the sigmoid notch. The volar radiolunate ligament originates from the lunate fossa and creates the “critical” corner, which is crucial for volar radiocarpal stability. Finally, the medial column is the distal ulna and the distal radio-ulnar joint. It is responsible for DRUJ stability and the normal rotation of the radius around the ulna.

In 2005, Medoff presented a fragment-specific classification system where he recognized five major fragment elements and proposed the separate fixation of each column. ³⁴ In 2016, Brink and Rikli indicated the “key” corner as the fragment where the lunate and the proximal row go in sagittal views. This fragment is not necessarily the largest one, and its reduction and stabilization should be the priority of the surgery strategy. ³⁵ In a most recent study, Hintringer et al proposed the definition of key fragments based on the CT scan. The choice of the right implant and approach should be based on the definition of these key fragments. ^{36 37}

In our cases, by direct visualization of the radial styloid surface, the anatomic reduction and fixation of the radial column are well achieved. This provides primary radiocarpal stabilization and the restoration of radius shortening and inclination. In simple fractures with no styloid process comminution, radial column stabilization will provide a stable first “landmark” for the rest of the procedure. In more complex fractures with comminution, radial styloid is challenging to be fixed through classic volar and dorsal approaches and, usually, another approach is required. ³⁸ We propose that this approach should be made through the same incision as the modified volar approach we described. The comminution is managed by direct visualization, and an anatomic plate can be well placed. At the same time, the brachioradialis tendon is detached, and the main deforming force is eliminated. ³⁹

The trans-FCR approach leads to a more ulnar sight of the distal radius, providing better visualization of the DRUJ and sigmoid notch. ⁵ With the described technique, the lunate corner reduction is guided by the already-fixed radial column, and as one piece, the hole radiocarpal articular surface is reduced to the proximal radius metaphysis. This way, the second intermediate column is also restored. Additionally, sigmoid notch reduction guarantees an anatomic articular surface between distal radius and ulna and, in most cases, realigns ulnar styloid fractures and triangular fibrocartilage. ^{40 41 42} This way, two columns are directly fixed, the third column is indirectly fixed, and four of five distal radius surfaces are visualized and reducted.

Immediate mobilization seems to be the best choice after DRF internal fixation to have a quicker recovery of ROM and strength. ⁴³ In our cases, we choose to immobilize the wrist for 2 weeks to protect the dorsal cortex which is often comminuted. Additionally, in cases of concomitant ulnar styloid fracture, this immobilization seems to facilitate the healing of the triangular fibrocartilage complex tear and the stability of the DRUJ. ^{40 42}

There are cases that this treatment option is insufficient ⁴⁴ or even contraindicated. Surgical fractures of the lateral ulnar column ^{40 41} and fractures with comminution in the elderly need additional interventions. Dorsal shear fractures and dorsal articular impacted fractures with undisplaced volar cortex should be managed with a dorsal approach. ²⁹

There are limitations to this study. First of all, it is a retrospective type of study. Even though our results are similar to those of other studies, ^{4 30 45 46} the described technique is not compared with another one. Consequently, there cannot be a safe conclusion about its superiority or inferiority to other fixation methods. Also, the follow-up period is short to evaluate long-term complications such as tendon irruptions, first compartment tendon subluxation, or the development of osteoarthritis. Another limitation is that there are no clear indications about the radial styloid type of fixation. In our cases, we choose to fix the radial styloid by plate or by K-wire, guided by the fracture comminution. However, there is no clear evidence about which one has better biomechanical and clinical results. Finally, some of our cases were not evaluated based on a CT scan that might affect the fracture classification.

Conclusion

Three-column fixation through the same palmar approach is a technique that allows the basic principles of fixation to be applied and wrist anatomy and biomechanics to be restored. Radial styloid can be fixed with direct visualization, and articular surfaces can be anatomically reduced. The best postoperative results can be expected with three-column fixation and four of five surfaces inspected. The proposed approach requests an excellent knowledge of anatomy to prevent complications of painful neuromas or radial artery injury.