Operative treatment of the post-traumatic boutonnière deformity. A modification of the direct anatomical repair technique

Flexor Digitorum Superficialis tendon transfer for a long-standing boutonniere deformity finger - a retrospective study of 11 cases

INTRODUCTION

A long-standing boutonniere deformity is challenging to treat because of well-established complex pathophysiological changes in the extensor expansion mechanism. The role of ulnar slip flexor digitorum superficialis tendon transfer for central slip reconstruction in such chronic deformities is analyzed and correlated with the functional outcome.

HYPOTHESIS

Ulnar slip FDS tendon corrects the long-standing boutonniere deformity and replicates anatomical repair.

METHODS

We conducted a retrospective study between 2014 and 2016 and operated on 11 patients by FDS tendon transfer to the extensor expansion's central slip. We compared the preoperative and postoperative range of movements in the proximal interphalangeal joint, distal interphalangeal joint, Visual analogue score, and grip strength. Also, we statistically correlated various parameters and non-parameters affecting the functional outcomes.

RESULTS

The mean time interval between the injury and surgery was 39 months. The average follow-up of our study was 15.4 months. Ten of the 11 patients had good functional outcomes with statistically significant improvement in the movements and grip strength (p<0.05).

CONCLUSIONS

Ulnar slip FDS tendon transfer is effective for central slip reconstruction in a long-standing boutonniere deformity. Minimal degrees of proximal interphalangeal joint extension deficit is inevitable due to the chronicity and adaptive changes in the ligament-tendon-bone complex.

LEVEL OF EVIDENCE

IV; retrospective case study.

Anatomic Repair of the Central Slip with Anchor Suture Augmentation for Treatment of Established Boutonniere Deformity

Backgroud

The rupture of the central slip of an extensor tendon of a finger causes a boutonniere (or buttonhole) deformity, characterized by pathologic flexion at the proximal interphalangeal (PIP) joint and hyperextension at the distal interphalangeal (DIP) joint. Currently, there are no standard treatment guidelines for this deformity. This study aimed to report clinical results of surgery to correct chronic boutonniere deformity.

Methods

This retrospective case series was conducted between January 2010 and December 2018 and only 13 patients with trauma-induced chronic deformity were included. After excision of elongated scar tissue, a direct anatomic end-to-end repair using a loop suture technique with supplemental suture anchor augmentation was conducted. Total active motion was assessed before and after surgery and self-satisfaction scores were collected from phone surveys.

Results

All patients presented with Burton stage I deformities defined as supple and passively correctable joints. The initial mean extension lag of the PIP joint (43.5°) was improved by an average of 21.9° at the final follow-up (p < 0.001). The mean hyperextension of the DIP joint averaged 19.2° and improved by 0.8° flexion contracture (p < 0.001). The average total active motion was 220.4° (range, 160°–260°). Based on the Souter's criteria, 69.2% (9/13) of the patients had good results. Only 1 patient reported fair outcome and 23.1% (3/13) reported poor outcome. The average Strickland formula score was 70 (range, 28.6–97.1). In total, 10 patients (77%) had excellent or good results. Of 10 patients contacted by phone, self-reported satisfaction score was very satisfied in 2, satisfied in 3, average in 3, poor in 1, and very poor in 1. Three patients reported a relapse of the deformity during range of motion exercises, 1 of whom underwent revision surgery. One patient complained of PIP joint flexion limitation, and 2 complained of DIP joint flexion limitation at final follow-up.

Conclusions

In chronic boutonniere deformity, central slip reconstruction with anchor suture augmentation can be an easily applicable surgical option, which offers fair to excellent outcome in 77% of the cases. The risk of residual extension lag and recurrence of deformity should be discussed prior to surgery.

Reconstruction of Traumatic Central Slip Injuries: Technique Using a Slip of Flexor Digitorum Superficialis

Multiple reconstruction techniques have been described for correction of boutonniere deformities including direct repair, central slip reconstruction, lateral band reconstruction, transverse retinacular ligament reconstruction, staged reconstruction, and extensor tenotomy. Each technique has been reported to have variable results with complications including capsular contracture, loss of proximal interphalangeal flexion, and residual deformity. We describe a surgical technique for central slip reconstruction using a slip of the flexor digitorum superficialis tendon through a bone tunnel.

Treating the Proximal Interphalangeal Joint in Swan Neck and Boutonniere Deformities

Swan neck and boutonniere deformities of the proximal interphalangeal (PIP) joint are challenging to treat. In a swan neck deformity, the PIP joint is hyperextended with flexion at the distal interphalangeal (DIP) joint. In a boutonniere deformity, there is flexion the PIP joint with hyperextension of the DIP joint. When the deformities are flexible, treatment begins with splinting. However, when the deformity is fixed, serial casting or surgery is often necessary to restore joint motion before surgical correction. Many surgical techniques have been described to treat both conditions. Unfortunately, incomplete correction and deformity recurrence are common.

Posttraumatic Boutonnière and Swan Neck Deformities

Boutonnière and swan neck deformities of the finger can be the result of trauma. The complex anatomy of the extensor mechanism of the finger makes understanding the pathomechanics of these deformities challenging. These posttraumatic deformities should not be confused with those associated with inflammatory arthritis because the treatment options are often very different. An accurate clinical assessment is essential for selecting the appropriate treatment method. Physical examination, including Elson and intrinsic-plus tests, and plain radiography are important tools for diagnosis. A variety of nonsurgical and surgical treatment modalities can be used to restore the motion of the proximal and distal interphalangeal joints and rebalance the forces across these joints. An understanding of the anatomy, clinical presentation, treatment options, and expected outcomes is crucial for optimal treatment of posttraumatic boutonnière and swan neck deformities.

Extensor tendons injuries

Extensor mechanism injuries are frequently encountered in athletes and can lead to permanent disability or deformity if not promptly and properly treated. This article reviews basic anatomy, and then discusses mallet finger injuries, boutonniere deformity, and sagittal band rupture. Once treatment has begun, return to sport is highly variable because of the varied needs of each athlete and where they fall on the spectrum of disease. As such, each athlete must be carefully evaluated and closely followed to ensure a safe, prompt, and judicious return to athletic pursuits.

Boutonnière and pulley rupture in elite athletes

This article discusses injuries to the central slip (boutonnière) and to the annular pulleys in the digit, with an emphasis on the elite athlete. Pertinent anatomy, mechanism of injury, diagnosis, treatment, and a discussion emphasizing the elite athlete and return to play form the basis of the article.

SURGICAL MANAGEMENT OF CHRONIC BOUTONNIERE DEFORMITY

Purpose: Boutonniere deformity is caused by damage to the central slip of the extensor tendon hood with secondary palmer migration of the lateral bands. Accordingly, patients complain of disfigurement and impairment of function due to hyperextension of their DIP. The aim of this study is to evaluate the results of surgical treatment of chronic boutonniere deformity by using a modified technique.

Patients and methods: Twelve patients with posttraumatic boutonniere deformity were available for follow up as a retrospective study. They were treated by release of the extensor expansion proximal to the distal insertion of the oblique retinacular ligaments with proximal recession of the extensor tendon and lifting the lateral bands dorsally onto the PIP joint after separation of the transverse retinacular ligaments from their insertion volarly. All patients had closed injury. The mean age was 32 years (range: 16–48 years). The average follow-up period was 33 months (range: 26–38 months). We included only cases with deformities that were totally correctable passively with or without joint osteoarthritic changes.

Results: Preoperatively the average PIP joint extension deficit was 60° and postoperatively the average is reduced to 7°, preoperative the average DIP motion was 10° of hyperextension, post-surgery the average DIP active flexion was 75°. The final outcomes were 58.3% excellent, 33.3% good, and 8.3% poor.

Discussion: This modified technique gave (91.6%) excellent and good results. The extensor tendon acted mainly on the PIP joint and allowing the DIP joint to flex freely. The procedure is simple and provides long-term good results.

Level of evidence: Therapeutic case series, level 1V.

Reconstruction of the extensor central slip using a distally based flexor digitorum superficialis slip

Several methods have been reported for reconstruction of the extensor central slip. We describe the successful use of a distally based slip of the flexor digitorum superficialis tendon for the reconstruction of an incompetent central slip of the extensor mechanism. The flexor digitorum superficialis tendon was transferred from volar to dorsal through the base of the middle phalanx and then woven through the extensor tendon over the proximal phalanx. The technique is straightforward and appears to be robust.

[The traumatic boutonnière deformity]

The traumatic boutonnière (or buttonhole) deformity develops after unsuccessful primary treatment of a lesion of the extensor tendon at the level of the proximal interphalangeal joint. Knowledge of the mechanisms leading to this deformity is fundamental for choosing and executing reconstructive procedures. The most frequently used methods are illustrated in this article. Because none of these procedures has been shown to be successful in all situations, we recommend a staged reconstructive approach. Even then, this deformity often results in incomplete reconstruction. Therefore, for these lesions especially, correct primary diagnostics and repair are required.

A prospective review of open central slip laceration repair and rehabilitation

A prospective review was carried out to evaluate the outcome of surgically repaired open central slip (zone III) injuries which were treated with 3 weeks of proximal interphalangeal joint immobilization within a cylinder splint and then with 3 weeks of controlled mobilization within a Capener coil splint. Thirty-one fingers in 27 patients were assessed by the same independent therapist. All fingers achieved an excellent or good recovery with a mean proximal interphalangeal joint flexion of 94 degrees (range 70-110 degrees) and a mean distal interphalangeal joint flexion of 57 degrees (range 30-81 degrees). Extension deficits of the proximal interphalangeal joint were noted in five fingers (mean 6 degrees, range 3-15 degrees). The results show that a combination of immobilization and controlled mobilization is an effective rehabilitation regime for surgically repaired open central slip injuries.

[Surgical treatment for boutonniere deformity of the fingers. Retrospective study of 47 patients]

Disruption or laceration of the central slip of the extensor tendon at the proximal interphalangeal (PIP) joint with volar displacement of the lateral bands can result in the so-called boutonniere deformity which includes loss of extension at the PIP joint and compensatory hyperextension of the distal interphalangeal (DIP) joint. Many procedures has been described in the literature and no standard treatment can be recommended. The authors reports a series of 47 cases of posttraumatic boutonniere deformity. The mean follow-up was five years. Majority of patients were males (38 males). The mean age was 41 years-old (17-82 y.o.). The etiology was in 23 cases a missed subcutaneous disruption of the central slip of the extensor tendon and in 24 cases an inappropriate treatment of laceration of the extensor apparatus at the dorsal aspect of the PIP joint. The involved digit was in seven cases the index finger, in 14 cases the long finger, in 14 cases the ring finger and in 12 cases the little finger. It is essential to distinguish the supple boutonniere deformity without or after physical therapy (34 cases) and the stiff boutonniere deformity even after a hand physical therapy program (13 cases). Results were assessed on pain and active range of motion of the PIP joint as well as the range of motion of the DIP joint. Supple boutonniere deformities, except one treated by an isolated distal tenotomy of the extensor tendon (1/34), was treated by a procedure of reconstruction of the extensor apparatus including resection-suture of the central slip and redorsalisation of the lateral bands when there was a DIP hyperextension with a moderate flexion deformity of the PIP joint, and (33/34) with 90% of excellent and good results. Poor results (4/33) were due in two cases to the absence of physical therapy, in one case to septic osteoarthritis and in one to secondary rupture of the suture. For the 13 stiff boutonniere deformities, when the PIP flexion deformity was moderate, a distal tenotomy performed to correct the DIP hyperextension was satisfactory in three cases with a useful result (20 degrees-70 degrees). For destroyed PIP joint (osteoarthritis), two silicone spacers were implanted with also a satisfactory result (30 degrees-70 degrees). In the eight remaining cases, a teno-arthrolysis was performed combined with a reconstruction of the extensor apparatus as described. Six poor results were obtained with arthritic PIP joints (which should have required initially silicone implants), and two fair results (30 degrees-60 degrees) with non-destroyed PIP joints. Supple boutonniere deformity must always be treated by initial physical therapy. Surgical procedure with reconstruction of the extensor apparatus is satisfactory if the PIP joint is normal. When there is PIP osteoarthritis, it may be beneficial to perform a two-stage technique with tenoarthrolysis followed hand therapy and a secondary reconstruction of the extensor apparatus as these last procedure give satisfactory results on a supple boutonniere deformity.