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Revista Brasileira de Ortopedia

versión impresa ISSN 0102-3616versión On-line ISSN 1982-4378

Rev. bras. ortop. vol.53 no.2 São Paulo marzo/enero 2018

http://dx.doi.org/10.1016/j.rboe.2018.02.010 

Artigos Originais

Ligamentous reconstruction of the interosseous membrane of the forearm in the treatment of instability of the distal radioulnar joint

Márcio Aurélio Aitaa 

Ricardo Carvalho Mallozia  * 

Willian Ozakia 

Douglas Hideo Ikeutia 

Daniel Alexandre Pereira Consonib 

Gustavo Mantovanni Ruggieroc 

aFaculdade de Medicina do ABC, Santo André, SP, Brazil

bUniversidade da Cidade de São Paulo (Unicid), Faculdade de Medicina, Santo André, SP, Brazil

cUniversità degli Studi di Milano, Milão, Italy

ABSTRACT

Objectives:

To measure the quality of life and clinical outcomes of patients treated with interosseous membrane (IOM) ligament reconstruction of the forearm, using the brachioradialis (BR), and describe a new surgical technique for the treatment of joint instability of the distal radioulnar joint (DRUJ).

Methods:

From January 2013 to September 2016, 24 patients with longitudinal injury of the distal radioulnar joint DRUJ were submitted to surgical treatment with a reconstruction procedure of the distal portion of the interosseous membrane or distal oblique band (DOB). The clinical-functional and radiographic parameters were analyzed and complications and time of return to work were described.

Results:

The follow-up time was 20 months (6-36). The ROM averaged 167.92° (93.29% of the normal side). VAS was 2/10 (1-6). DASH was 5.63/100 (1-18). The time to return to work was 7.37 months (3-12). As to complications, one patient had an unstable DRUJ, and was submitted to a new reconstruction by the Brian-Adams technique months. Currently, he has evolved with improved function, and has returned to his professional activities. Three other patients developed problems around the transverse K-wire and were treated with its removal, all of whom are doing well.

Conclusion:

The new approach presented in this study is safe and effective in the treatment of longitudinal instability of the DRUJ, since it has low rate of complications, as well as satisfactory radiographic, clinical, and functional results. It allows return to social and professional activities, and increases the quality of life of these patients.

Keywords: Forearm injuries/surgery; Joint range of motion; Joint instability; Membranes/injuries; Joint ligaments

Introduction

Forearm, wrist and elbow fractures can occur separately or associated, and account for one-sixth of the cases in orthopedic emergency rooms. They may be associated with injury to the interosseous membrane (IOM) of the forearm and, when not adequately treated, alter the anatomy, stability, and load transmission through the wrist, forearm, and elbow, resulting in pain, and decreased range of motion and palmar grip strength that may lead to the inability to perform activities of daily life (ADL).1

The IOM is a fibrous tissue that runs obliquely through the radius and the ulna.2 It is a complex of ligaments and membranes that stabilize the distal radioulnar joint (DRUJ) during pronation and supination movements. Its main region is the central band, in its oblique portion.3,4 The distal oblique band (DOB) is located in the distal portion of the IOM around the DRUJ, which originates in the distal third of the ulna and is inserted into the lower edge of the sigmoid notch of the radius (Fig. 1). Moreover, DOB appears to present a continuity with the dorsal and palmar radioulnar ligaments of the triangular fibrocartilage complex. In their biomechanical study, Watanabe et al.5 affirmed the importance of the distal membranous portion of the IOM in the volar and dorsal stability of the radius in the DRUJ, in all rotational positions of the forearm. Kihara et al.6 described a “cooperation” between the DOB and the triangular fibrocartilage complex (TFCC), as the DOB forms a ligament within the distal membranous portion. However, further biomechanical research is needed to confirm this hypothesis.

Fig. 1 Schematic illustration of the IOM8; featuring the distal portion (DOB). 

High-energy trauma can damage the IOM and lead to longitudinal instability of the radioulnar joint (Fig. 2). It can also be associated with radius head or diaphyseal fractures and DRUJ dislocations (Essex-Lopresti and Galleazzi fracture-dislocations, respectively).

Fig. 2 Lateral and anteroposterior view radiographs of the wrist demonstrating the instability of the DRUJ. 

Some authors have attempted to biomechanically reproduce trauma energy dissipation in the structures of the forearm, and have described the Essex-Lopresti lesion. Miyake et al.7 determined that this lesion originates in the head of the radius, while Wegmann et al.8 stated that it occurs in the central portion of the IOM and dissipates in two directions: proximal, leading to radial head fracture; and distal, leading to DRUJ instability.

The diagnosis of these associated ligament lesions is difficult; the DRUJ should be checked through physical examination, with the ulnar drawer test in supination, pronation, and neutral positions, and should be compared with the non-affected side. In order to elucidate this diagnosis, an ultrasound exam or magnetic resonance imaging of the forearm is performed.9 The authors believe that the radiographic lateral view of the forearm associated with the ulnar drawer test, both with the forearm in a neutral position, establishes the diagnosis of DRUJ instability.

The traditional treatment method for acute longitudinal instability of the forearm consists of stabilizing the radius fracture and reducing DRUJ, whether or not associated through fixation with Kirschner wires or plaster cast immobilization. After 12 weeks, the radius fracture consolidates, but IOM healing does not always occur, especially in cases of anterior compartment muscle herniation. Thus, the diagnosis is late, and patients present chronic insufficiency of this joint and pain in the ulnar region of the wrist.9

The methods for ligament reconstruction in IOM lesions consist of the use of pronator quadratus, flexor carpi radialis, semitendinosus, patellar, and palmaris longus tendon grafts. However, the execution of these techniques is challenging and the results are unsatisfactory, with limited functional results.9

In the search for new treatments to correct DRUJ instability, the authors believe that DOB reconstruction restores the joint congruence between the ulnar head and the sigmoid fossa of the radius. The authors searched for methods that are reproducible and easy to perform; therefore, it was decided to use the brachioradialis (BR) muscle tendon, which is located in the mid-third of the forearm and inserts into the radial styloid, near the DOB. Its resection does not lead to functional loss of the limb.

Moreover, as an advantage, the DRUJ is not directly approached, the technique is easy to execute, and the BR insertion is preserved; this is a natural and anatomical point to support the deforming forces that lead to DRUJ instability.

This study is aimed at measuring the quality of life and the clinical-functional results of patients who underwent ligament reconstruction of the forearm IOM using the BR muscle tendon and to describe a new surgical technique in the treatment of DRUJ instability.

Methods

The study was approved by the Ethics Committee of the institution under the CAAE number: 50917315.9.0000.5484.

From January 2013 to September 2016, patients with longitudinal DRUJ instability were assessed at the outpatient hand surgery clinic of this institution and underwent surgical treatment, with the procedure of reconstruction of the oblique distal portion of the IOM, with the new technique proposed in this study.

Inclusion criteria: patients with clinical (positive drawer test) and imaging (lateral view radiograph showing dorsal deviation of the ulna in relation to the radius) diagnosis of longitudinal DRUJ instability. Both exams (clinical and radiographic) were performed with the forearm in neutral position (0° of pronation, 0° of supination). Exclusion criteria: patients who did not complete the stages of the study (abandoned the rehabilitation program or outpatient follow-up consultations).

The mean age was 36 years (11-60). Fifteen right and nine left forearms were operated on. Regarding the professional occupation, two patients were students, three housemaids; one veterinarian; one athlete; one computer technician; ten factory workers; three motorcycle couriers; one saleswoman; one nurse; and one businessman. Seven patients had a fracture of the distal extremity of the associated radius; seven, Essex-Lopresti lesions; two, Galleazzi fracture-dislocations; one, rheumatoid arthritis (Vaugh-Jackson syndrome); six, complete TFCC lesion; and one, Basel-Hagen deformity. All patients presented pain in the ulnar region of the wrist, especially at the extremes of range of motion and on exertion; they also reported a sensation of instability, with painful clicking. Physical examination revealed pain at DRUJ palpation, and the ulnar drawer test was positive in all patients (Table 1). Subsequently, the patients were evaluated by the occupational therapy sector at regular intervals in the postoperative period; they followed a pre-established program (activities for analgesia and proprioception, passive and active gain of forearm pronation and supination; palmar grip strength gain, and training for ADL and work activities). Outpatient follow-up consultations were held on the second and sixth weeks, sixth months, and one year after the surgical procedure.

Table 1 Epidemiological aspects of the patients included in this study. 

Identification Age Follow-up Side ROM 1 year DASH 1 year VAS 1 year Return to work Complications Profession Reason
I 29 34 R 180 1 1 Before 3 months N Motorcycle courier Essex-Lopresti
II 25 32 L 130 10 3 Before 12 months Y - instability Factory worker Wrist fracture - TFC
III 25 36 R 180 1 1 Before 6 months N Computer technician Essex-Lopresti
IV 32 35 L 180 9 2 Before 6 months N Saleswoman Rheumatoid arthritis - MUH
V 25 29 R 150 10 3 Before 12 months N Motorcycle courier Essex-Lopresti
VI 38 29 R 170 5 2 Before 12 months N Factory worker Wrist fracture - TFC
VII 50 26 L 150 5 4 Before 12 months N Factory worker Wrist fracture - TFC
VIII 28 25 R 125 18 3 Before 12 months N Factory worker Complex TFCC
IX 43 24 R 155 1 2 Before 3 months N Nurse Wrist fracture - TFC
X 50 20 R 180 2 6 Before 12 months N Housemaid Complex TFCC
XI 45 20 L 180 1 1 Before 12 months N Factory worker Wrist fracture - TFC
XII 39 17 R 180 1 1 Before 6 months N Athlete Essex-Lopresti
XIII 57 19 R 180 1 2 Before 12 months N Housemaid Essex-Lopresti
XIV 32 14 R 180 1 2 Before 3 months N Veterinarian Complex TFCC
XV 28 14 L 180 1 2 Before 6 months N Factory worker Complex TFCC
XVI 19 16 L 180 1 1 Before 3 months N Motorcycle courier Galeazzi
XVII 35 20 R 180 1 1 Before 12 months Y - Loose screw Factory worker Complex TFCC
XVIII 11 13 R 180 6 1 Before 6 months N Student Bassel-Hagen
XIX 38 11 L 180 12 2 Before 6 months N Factory worker Complex TFCC
XX 36 10 L 160 12 2 Before 6 months N Factory worker Essex-Lopresti
XXI 32 10 R 155 12 2 Before 6 months Y - broken K-wire Factory worker Galeazzi
XXII 60 6 R 150 12 1 Before 3 months Y - K-wire secretion Businessman Wrist fracture - TFC
XXIII 15 6 L 180 6 1 Before 3 months N Student Wrist fracture - TFC
XXIV 57 6 R 165 6 2 Before 3 months N Housemaid Essex-Lopresti

Source: Medical Statistical File Service.DASH, Disability Arm, Shoulder and Hand Questionnaire; TFC, triangular fibrocartilage; N, no; Y, yes; TFCC, triangular fibrocartilage complex; VAS, visual analogue scale.

The analyzed parameters were:

  • - Range of motion (ROM) - goniometry of the range of motion, measured in degrees;

  • - DASH (Disabilities of the Arm, Shoulder, and Hand Questionnaire) - quality of life;

  • - VAS (visual analogue scale) - subjective pain assessment;

  • - Radiographic assessment to visualize reduction of dorsal ulna dislocation on a lateral view, with the forearm in the neutral position;

  • - Description of the complications that arose after surgical treatment;

  • - Time of return to work.

Description of the surgical technique (Figs. 3 and 4)

Fig. 3 Photograph of a cadaveric specimen and illustrative drawing demonstrating the technique of DOB reconstruction with BR. 

Fig. 4 Intraoperative clinical and radiographic aspects demonstrating BR tendon grafting. 

  1. Longitudinal dorsal-radial incision of 10 cm in the affected forearm.

  2. Fine dissection in layers of the subcutaneous tissue, radial artery, and radial nerve (sensory branches), with the aid of a microsurgical magnifying glass.

  3. Direct visualization and dissection of the BR muscle tendon from its insertion in the radial styloid until its proximal myotendinous transition in the forearm. It must not be detached from the styloid of the radius and must be used entirely in the myotendinous region; section the tendon of the muscle to form the stump to be transferred. Preparation of the graft stump with Krackow suture using a specific fiberwire (FiberLoop™, Arthrex Inc., FL, USA).

  4. A radial and ulnar tunnel is made, oblique, proximally in the radius and distally in the ulna, with a specific drill, under indirect vision and with the aid of radioscopy.

  5. Passage of the tendon through the radial and ulnar tunnel with the aid of a specific guidewire.

  6. Fixation of the graft with two specific mini-interference or bio-tenodesis screws (Bio-Tenodesis™ screw, Arthrex Inc., FL, USA), one in each tunnel, to tension the system in order to stabilize the DRUJ. Perform the ulnar drawer test to ensure the stability of this joint. Fixation of the forearm in the neutral position, with a transverse Kirschner wire, passing through the radius and ulna, blocking pronosupination for six weeks.

  7. Hemostasis, cleansing, and suture by layers of the surgical access to the radius and ulna with radiographic imaging in posteroanterior (PA) and lateral (L) views of the wrist to check the position of the DRUJ and implants (K-wire and screws).

  8. Occlusive dressing and immobilization with a plaster cast.

  9. After the procedure, an orthosis should be maintained for six weeks. Subsequently, a rehabilitation program should be conducted in the occupational therapy sector of the institution, with the previously established specific protocol (Figs. 3 and 4).

Results

The mean follow-up time was 20 months (6-36). The mean range of motion (pronation + supination) was 167.92° (93.29% of the normal side). The mean VAS was 2/10 (range: 1-6). Regarding quality of life, the DASH score was 5.63/100 (range: 1-18).

The mean time of return to work was 7.37 months (range: 3-12). As for complications, one patient developed DRUJ instability and underwent reconstruction using the Brian-Adams technique, six months after the procedure described in this present study; the patient progressed with pain improvement, had a functional wrist range of motion, and returned to professional activities.

Two other patients evolved with Kirschner wire rupture; a surgical procedure was required for its successful removal.

One patient developed secretion in the path of the Kirschner wire, which improved after its removal. Lastly, a patient presented loosening of the ulnar screw, successfully removed in a surgical procedure. DRUJ stability, assessed by postoperative examination (ulnar drawer test) and wrist lateral view, radiographs was observed in 23/24 patients (95.83%; Fig. 5).

Fig. 5 Postoperative clinical and radiographic aspects after reconstruction. 

Three patients had partial supination limitation, probably due to excessive graft tension during the surgical procedure. No cases of infection or neurological and vascular complications were observed in this present study.

Statistical results

The significance level was set at 5% (0.050) for the statistical tests.

MS-Excel spreadsheet, in its MS-Office 2013 version, was used to organize the data. The statistical package SPSS (Statistical Package for Social Sciences), version 23.0, was used to calculate the results.

The Wilcoxon signed-rank test was used to verify possible differences between the two moments studied (Table 2) for the variables of interest.

Table 2 Clinical-functional results: patients included in this study. 

Variables n Mean Standard deviation Minimum Maximum 25th percentile 50th percentile (median) 75th percentile Significance (p)
Normal ROM 24 180.00 0.00 180.00 180.00 180.00 180.00 180.00 0.005
Final ROM 24 167.92 17.06 125.00 180.00 155.00 180.00 180.00
Normal DASH 24 1.00 0.00 1.00 1.00 1.00 1.00 1.00 0.001
Final DASH 24 5.63 5.08 1.00 18.00 1.00 5.00 10.00
Normal VAS 24 1.00 0.00 1.00 1.00 1.00 1.00 1.00 <0.001
Final VAS 24 2.00 1.18 1.00 6.00 1.00 2.00 2.00

Source: Medical Statistical File Service.ROM, range of motion; DASH, Disability Arm, Shoulder and Hand Questionnaire; VAS, visual analogue scale.

Discussion

The idea of IOM reconstruction is not new. The central portion is the most cited and studied in the literature. Clinical and cadaveric studies have demonstrated its biomechanical resistance. The literature describes IOM reconstruction with the use of a palmaris longus tendon graft, radial flexor carpi, Achilles tendon, pronator teres, and synthetic and patellar (bone-ligament-bone) materials in chronic lesions.9-15 Acute instabilities have been treated with DRUJ transverse fixation with Kirschner wire, with limited results.

The present series aimed to treat chronic and acute lesions in order to avoid instability and the complications resulting from it, such as radiocapitellar osteoarthrosis, ulnocarpal impact, and the reduction in the functional capacity of these limbs.9

The results of this present study demonstrated an improvement in the mobility of the elbow, forearm, and wrist, with 93.29% recovery when compared to the contralateral ROM (pronation + supination), thus higher than the study by Adams et al.,9 in which IOM reconstruction was also performed, with 86.11% ROM recovery.

Recently, an intraoperative “radio joystick test” was described and tested on cadavers to improve the diagnosis of IOM injuries.16 Lateral traction is applied to the neck of the proximal radius while the forearm is completely pronated. The examiner visualizes the lateral displacement of the proximal radius, thus indicating an IOM lesion. This essay was 100% sensitive for the detection of this lesion and the positive predictive value was 90%. A study of this test in vivo has not yet been done.17 The authors believe that the ulnar drawer test also has an accuracy of close to 100%, and that the combination of these two tests would probably increase the certainty of the diagnosis.

The distal portion of the IOM is the DOB, which helps in transferring longitudinal loads between the radius and the ulna. When the ulnar variant is neutral, the radiocarpal joint absorbs 80% of the axial load transmitted through the wrist, the remaining 20% being transmitted to the ulna. The IOM continues to transfer loads from the radius to the ulna through the forearm (central portion) so that, at the elbow, the radiocarpal joint is subjected to 60% of the original axial load and the ulnar joint receives the remaining 40% (proximal oblique band).17 The authors suggest that the DOB is of fundamental importance in stabilizing longitudinal instabilities of the DRUJ, as described by Watanabe et al.5 and Kihara et al.6

The choice of the BR muscle tendon graft in the present study is unprecedented and offers some advantages:

  • - The diameter of the bone tunnels can be minimal, avoiding complications such as iatrogenic fractures of the radius and ulna;

  • - It preserve the insertion, which the authors believe helps during the surgical act to tension the graft;

  • - The location is adjacent to the DRUJ, which avoids approaching another surgical site, such as the knee (for removal of bone-ligament-bone);

  • - Its removal does not affect the function of the donor forearm.

DRUJ longitudinal instability recurrence is often cited in the literature17; the present results demonstrated a maintenance of this reduction in 23/24 patients (95.83%).

Replacing a ligament through a tendon cannot actually reproduce the original anatomy of the SL complex. However, the authors believe in the “ligamentization” of these grafts, since the environment in which they are found may favor this mechanism, similarly to what is observed in patients who undergo anterior cruciate ligament (ACL) reconstruction.18

In the following lesions, DOB reconstruction should be associated, since they present instability of the DRUJ, with indication of IOM reconstruction, and better treatment efficacy:

  • - Radial head osteosynthesis (Essex-Lopresti);

  • - Radial head arthroplasty (Essex-Lopresti);

  • - Osteosynthesis of the radial diaphysis (Galleazzi);

  • - Osteosynthesis of the distal end of the radius (complete TFCC lesions).

Many cadaver studies support the reconstruction of the central portion of the IOM. Pfaeffle et al.14 stated that the double band of the flexor carpi radialis (FCR) for IOM reconstruction showed the longitudinal and transverse resistance of an intact IOM. Other clinical studies have shown promising results, associating ulnar shortening osteotomy with IOM reconstruction.11 The authors have been able to demonstrate satisfactory results in reconstructions isolated or associated to radial osteotomies, osteosynthesis, and arthroplasties in this present study.

This study presented the case of a patient diagnosed with Basel-Hagen disease (hereditary multiple exostosis), associated with elbow stiffness, dislocation of the radius head, and longitudinal DRUJ instability. The authors performed ulnar lengthening with a uniplanar external fixation device, resection of the distal ulna osteochondroma, DOB reconstruction with the graft described in the present study, and, finally, radial reduction, achieving adequate length of the ulna, DRUJ stabilization, and functional gains in the elbow, forearm, and wrist (Figs. 6 and 7).

Fig. 6 Pre and postoperative radiographic aspects of the patient (ulnar lengthening). 

Fig. 7 Post-operative clinical and radiographic aspects of IOM reconstruction and radial head reduction. 

Conclusion

The new approach presented in this study has shown to be safe and effective in the treatment of longitudinal DRUJ instability, since it presented a low rate of complications and satisfactory radiographic, clinical, and functional results, improving the quality of life of these patients.

Study conducted at Faculdade de Medicina do ABC, Centro Hospitalar Municipal de Santo André, Serviço de Ortopedia e Traumatologia, Santo André, SP, Brazil.

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Recibido: 29 de Septiembre de 2016; Aprobado: 2 de Diciembre de 2016

* Corresponding author. E-mail: mallozi.ricardo@gmail.com (R.C. Mallozi).

Conflicts of interest

The authors declare no conflicts of interest.

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