The swan neck deformity sign

Purpose: Proximal phalangeal bone fractures with displacement are treated using operative procedures. These fractures can cause stiffness of the interphalangeal or metacarpophalangeal joints, which can be relieved using various operative and nonoperative techniques. This study analyzed the range of motion (ROM) and pain after a combination therapy to treat finger stiffness following proximal phalangeal fractures.Methods: Fifty-two patients who underwent operative procedures for proximal phalangeal fractures and showed finger stiffness from March 2015 to January 2021 were included in this retrospective study. The patients in group 1 (n=24) performed elastic resistance exercises, while those in group 2 (n=28) underwent conventional exercise. ROM and pain score were measured at 5, 8, and 12 weeks postoperatively. Furthermore, a patient with a swan-neck deformity and intractable stiffness was treated using partial translocation of the extensor apparatus, and the postoperative outcome is presented.Results: Group 1 showed a larger ROM and less pain than group 2 at 12 weeks postoperatively (p<0.05). Patients in both groups exhibited notable improvements with regard to ROM and pain during the study period (p<0.05). In addition, the swan-neck deformity accompanying hyperextension of the proximal interphalangeal joint was significantly relieved.Conclusion: Proximal phalangeal bone fractures can lead to stiffness of the interphalangeal and metacarpophalangeal joints. Joint stiffness was relieved using an elastic resistance exercise protocol in the early postoperative period. Intractable stiffness showing a fixed joint angle can be treated with thorough tenolysis and corrective surgery.

Download Full-text

Swan-Neck Deformity of the Cervical Spine Following Multiple Laminectomies in a Child with Neurofibromatosis: A case report

The Journal of the Korean Orthopaedic Association ◽

10.4055/jkoa.1976.11.4.681 ◽

1976 ◽

Vol 11 (4) ◽

pp. 681

Keyword(s):

Case Report ◽

Cervical Spine ◽

Swan Neck Deformity

Download Full-text

Correction of Swan Neck Deformity in Rheumatoid Arthritis Using a New Lateral Extensor Band Technique

Journal of Hand Surgery (European Volume) ◽

10.1177/1753193408092787 ◽

2008 ◽

Vol 33 (6) ◽

pp. 712-716 ◽

Cited By ~ 16

Author(s):

M. SIROTAKOVA ◽

A. FIGUS ◽

P. JARRETT ◽

A. MISHRA ◽

D. ELLIOT

Keyword(s):

Flexor Digitorum Superficialis ◽

Palmar Plate ◽

Pip Joint ◽

Distal Interphalangeal ◽

Distally Based ◽

Student’S T ◽

Flexor Digitorum ◽

Swan Neck Deformity ◽

Student’S T Test

Swan neck deformity is a progressive and disabling condition that commonly affects rheumatoid arthritic hands. During a 4-year period, 101 fingers in 43 patients had this deformity corrected using a new procedure combining the distally based extensor lateral band technique described by Littler and the flexor digitorum superficialis (FDS)-palmar plate pulley introduced by Zancolli. The ranges of motion of the metacarpophalangeal, proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints were assessed pre-operatively and 12 months after surgery. An average PIP joint hyperextension of −13.3° was converted to +13.4°. The ranges of motion of the proximal and DIP joints were significantly different (Student’s t-test). No patient suffered recurrence of the deformity during an average follow-up of 20 months. This new technique improves some unappealing aspects of previous techniques and provides a stable and reliable correction of swan neck deformity.

Download Full-text

Development of an In Vitro Swan Neck Deformity Biomechanical Model

Hand ◽

10.1177/1558944720966736 ◽

2020 ◽

pp. 155894472096673

Author(s):

Mohammad M. Haddara ◽

Stacy Fan ◽

Bogdan A. Matache ◽

Shrikant J. Chinchalkar ◽

Louis M. Ferreira ◽

...

Keyword(s):

In Vitro Model ◽

Volar Plate ◽

Strong Positive Correlation ◽

Mallet Finger ◽

Active Motion ◽

Motion Simulator ◽

Flexion Extension ◽

Vitro Model ◽

Swan Neck Deformity

Background: Injury to the finger’s extensor mechanism is a common cause of swan neck deformity (SND). Progression of extensor and flexor tendon imbalance negatively affects laxity of the volar plate, resulting in the inhibition of proper finger motion. The complexity of finger anatomy, however, makes understanding the pathomechanics of these deformities challenging. Therefore, development of an SND model is imperative to understand its influence on finger biomechanics and to provide an in vitro model to evaluate the various treatment options. Methods: The index, middle, and ring fingers from 8 cadaveric specimens were used in an in vitro active motion simulator to replicate finger flexion/extension. An SND model was developed through sectioning of the terminal extensor tendon at the distal insertion (creating a mallet finger) and transverse retinacular ligament (TRL). A strain gauge inserted under the volar plate measured laxity of the plate, and electromagnetic trackers recorded proximal interphalangeal joint (PIPJ) angles. Results: Strain in the volar plate increased progressively with creation of the mallet and SND conditions ( P = .015). Although not statistically significant, the mallet finger condition accounted for 26% of the increase, whereas sectioning of the TRL accounted for 74% ( P = .031). As predicted, PIPJ hyperextension was not detectable by joint angle measurement; however, the PIPJ angle had a strong positive correlation with volar plate strain ( R2 = 1.0, P < .001). Conclusion: Volar plate strain measurement, in an in vitro model, can detect an induced SND. Moreover, as a surrogate for PIPJ hyperextension, volar plate strain may be useful to evaluate the time-zero effectiveness of various surgical interventions.

Download Full-text