Hand Surgery Source

SPRAIN, DIP JOINT

Introduction

Injuries to the distal interphalangeal (DIP) joint, which range from mild sprains to complete ligament ruptures and joint dislocations, are uncommon and occur less frequently than those of the proximal interphalangeal (PIP) and metacarpophalangeal (MP) joints. The low incidence of DIP joint sprains is believed to be due to the joint’s anatomic stability and short lever arm, which protect it from injury. DIP joint sprains can result from either a hyperextension or laterally deviating force, which can injure the volar plate or collateral ligament, respectively, and a complete rupture may occur if the force is strong enough. These injuries typically have an excellent prognosis, but prolonged immobilization of the DIP joint can cause stiffness and may result in irreversible loss of motion in the digit. This shows why a timely and accurate diagnosis and appropriate treatment are needed to prevent long-term complications.1-3

Pathophysiology

  • The primary mechanism responsible for volar plate sprains of the DIP joint is a hyperextension force, while collateral ligament injuries are more likely to occur from a laterally deviating force to the fingertip. If one of these forces is strong enough, it can cause a complete tear of one of a collateral ligament.2,4
  • A disruption of any of the important DIP joint structures will impact the coordinated gliding motion of tendons and ligaments and impair the range of motion (ROM) of the joint.5
  • The low incidence of DIP joint sprains may be due to its relative stability compared with that of the PIP joint, which is primarily imparted by the extensive adherent soft tissues. The distal phalanx is also shorter than the middle and proximal phalanges, which provides a shorter lever arm and therefore less torque for inducing injury.1

Related Anatomy6,7

  • Ulnar collateral ligament (UCL): proper and accessory
  • Radial collateral ligament (RCL): proper and accessory
  • Dorsal capsule
  • Volar plate
  • The DIP joint is a hinge joint that functions similarly to the PIP joint: the RCL, UCL, and volar plate remain present, but the lateral bands and terminal insertion of the extensor mechanism provide dorsal support.1
  • The DIP joint also has less motion than the PIP joint, ranging from 0-80° of flexion/extension compared to 0-110°, respectively.1
  • Although the DIP joint is only responsible for 15% of each digit’s total active ROM, it is important for generating a power grip, and the loss of total DIP joint flexion can be detrimental to overall hand strength and functional capability.8
  • Ligamentous injuries of the DIP joint are typically classified using the following system:
    • Grade 1: involves asymmetric swelling and tenderness over the collateral ligament without instability on the lateral stress test
    • Grade 2: involves complete disruption of the collateral ligament, but the volar plate remains intact. There is some instability, but stress testing reveals a definite soft tissue endpoint indicating that the collateral is not completely torn.
    • Grade 3: involves total collateral ligament disruption and volar plate rupture, with clinical examination depicting evidence of subluxation or dislocation on active extension.4,9 Stress testing reveals no soft tissue endpoint indicating that the collateral ligament is completely torn.

Incidence and Related Conditions

  • One study found that finger injuries accounted for 38% of 3.5 million upper extremity injuries in the U.S. About 16% of these injuries were sprains and strains, while dislocations only accounted for ~5%.10
  • The incidence of finger sprains is 37.3 per 100,000 persons/year, and the PIP joint is the most commonly injured joint of the hand, followed by the thumb MP joint and then the MP joint of the fingers. Due to their infrequency, statistics are lacking on the specific occurrence rates of sprains to the distal interphalangeal (DIP) joint of the fingers and thumb interphalangeal (IP) joint.10

Differential Diagnosis

  • Collateral ligament tear
  • Volar plate tear
  • Extensor tendon avulsion/mallet finger
  • DIP joint dislocation
  • Middle phalanx fracture
  • Distal phalanx fracture
  • Mallet Finger Injury
ICD-10 Codes

SPRAIN

Diagnostic Guide Name

SPRAIN

ICD 10 Diagnosis, Single Code, Left Code, Right Code and Bilateral Code

DIAGNOSIS SINGLE CODE ONLY LEFT RIGHT BILATERAL (If Available)
- WRIST        
 - CARPAL JOINT   S63.512_ S63.511_  
 - RADIOCARPAL JOINT   S63.522_ S63.521_  
 - OTHER SPECIFIED SPRAIN OF WRIST   S63.592_ S63.591_  
- METACARPOPHALANGEAL (MCP)        
 - INDEX   S63.651_ S63.650_  
 - MIDDLE   S63.653_ S63.652_  
 - RING   S63.655_ S63.654_  
 - LITTLE   S63.657_ S63.656_  
 - THUMB   S63.642_ S63.641_  
- INTERPHALANGEAL (DIP, PIP)        
 - INDEX   S63.631_ S63.630_  
 - MIDDLE   S63.633_ S63.632_  
 - RING   S63.635_ S63.634_  
 - LITTLE   S63.637_ S63.636_  
- CARPOMETACARPAL OF THUMB (CMC)   S63.8X2_ S63.8X1_  

Instructions (ICD 10 CM 2020, U.S. Version)

THE APPROPRIATE SEVENTH CHARACTER IS TO BE ADDED TO EACH CODE FROM CATEGORY S63
A - Initial Encounter
D - Subsequent Routine Healing
S - Sequela

ICD-10 Reference

Reproduced from the International statistical classification of diseases and related health problems, 10th revision, Fifth edition, 2016. Geneva, World Health Organization, 2016 https://apps.who.int/iris/handle/10665/246208

Symptoms
History of finger trauma with DIP joint instability and/or deformity
Pain, swelling, and ecchymosis over the DIP joint
Decreased finger motion
Typical History

A typical patient is a 20-year-old, left-handed male who was exiting a car parked on a steep hill when he realized that he had forgotten his glasses. He quickly turned around and went to reach back in the car, but by this point the car door was in the process of shutting because of its angle. The door then shut on the long finger of his left hand and hyperextended its DIP joint, which caused a moderate sprain of the volar plate and led to pain, swelling, and tenderness over the joint.  The patient was subsequently seen by a hand surgeon who diagnosed a DIP joint sprain grade II and treated the patient with a Stack splint and later hand therapy.

Positive Tests, Exams or Signs
Work-up Options
Treatment Options
Treatment Goals
  • Control pain and swelling
  • Maintain stability, motion and strength, i.e. maintain function
Conservative
  • The goal of injury management for DIP joint sprains is to obtain a strong, stable, and pain-free joint with an optimum ROM.5
  • Treatment decisions should be based on the injury pattern, joint stability and level of chronicity, but the majority of DIP sprains can be effectively managed conservatively with a period of immobilization.2  Most authors recommend buddy taping and/or a sustained extension splint of the injured digit.11  Initial splinting should be done in complete or near-complete extension, and the splint should be used until the acute pain and swelling have subsided.  If full extension is not possible at first, then dynamic DIP extension splinting might be needed.12  Immobilization typically should not extend beyond 3 weeks, as doing so may lead to permanent stiffness.2
  • Nonsteroidal anti-inflammatory drug should only be used cautiously and for short period of time after review of the patient's medical history.9
  • Steroid injections may reduce pain and inflammation, but can be detrimental to healing. Most experts therefore caution against their use for acute DIP joint sprains.9
Operative
  • Ligamentous injuries of the DIP joint rarely require surgical intervention unless a ligament is completely ruptured. Rarely, grade 3 DIP injuries may need to be treated surgically to avoid chronic pain, swelling, joint instability, and dysfunction.9
  • Many types of repairs and reconstructions have been described for ligamentous ruptures of the DIP joint, in which sutures, bone anchors, tendon weaves, and various muscle-tendon advancements may be utilized.9
  • After surgery, the finger should be immobilized for up to several weeks, and continued physical therapy with active ROM exercises will be necessary to ensure a proper return of function.13
Complications
  • Stiffness
  • Infection if the injury was open or treated surgically
  • In general, the more traumatic the injury or the more involved the surgery is, the stiffer the joint will become.
  • DIP flexion deformity
  • Osteoarthritis
  • Swan neck deformity
  • DIP joint contracture
  • Pseudo-boutonniere deformity
  • According to some authors, most complications in DIP joint sprains are due to over-treatment—such as excessive immobilization—rather than the absence of treatment.11
Outcomes
  • DIP joint sprains typically have an excellent prognosis, and most patients will eventually regain full finger ROM; however, some patients will continue to experience pain, stiffness, and disability up to 3 months after the injury.3,11,14. The prognosis depends of the promptness of treatment, as injuries managed early are typically associated with more positive outcomes.11
Video
DIP Joint Area Exam
Key Educational Points
  • Many patients present several weeks or months after injury, at which point they still experience pain, swelling, and stiffness. This can lead some patients to protect the finger excessively, which results in additional stiffness and hinders their recovery.14
  • Over the past 10 years, there have been many advances in the understanding of the anatomy, physiology, and biomechanics of the ligamentous joint capsule of the finger joints, which may help to better deliver effective treatments to patients.9
  • Collateral ligament DIP joint sprains may be more difficult to diagnose than more obvious proximal injuries, and the true incidence of these injuries may therefore be higher than statistics suggest.1
  • Unstable DIP joint sprains can follow the same treatment protocols for reduced but unstable DIP dislocations, and stable, reduced DIP dislocations can be treated with the same approach as DIP sprains.2
References

New and Cited Articles

  1. Carruthers, KH, Skie, M and Jain, M. Jam Injuries of the Finger: Diagnosis and Management of Injuries to the Interphalangeal Joints Across Multiple Sports and Levels of Experience. Sports Health 2016;8(5):469-78.PMID: 27421747
  2. Prucz, RB and Friedrich, JB. Finger joint injuries. Clin Sports Med 2015;34(1):99-116. PMID: 25455398
  3. Draghi, F, Gitto, S and Bianchi, S. Injuries to the Collateral Ligaments of the Metacarpophalangeal and Interphalangeal Joints: Sonographic Appearance. J Ultrasound Med 2018;37(9):2117-2133. PMID: 29480577
  4. Kamnerdnakta, S, Huetteman, HE and Chung, KC. Complications of Proximal Interphalangeal Joint Injuries: Prevention and Treatment. Hand Clin 2018;34(2):267-288. PMID: 29625645
  5. Joyce, KM, Joyce, CW, Conroy, F, et al. Proximal interphalangeal joint dislocations and treatment: an evolutionary process. Arch Plast Surg 2014;41(4):394-7. PMID: 25075363
  6. Bowers, WH, Wolf, JW, Jr., Nehil, JL, et al. The proximal interphalangeal joint volar plate. I. An anatomical and biomechanical study. J Hand Surg Am 1980;5(1):79-88. PMID: 7365222
  7. Bowers, WH. The proximal interphalangeal joint volar plate. II: a clinical study of hyperextension injury. J Hand Surg Am 1981;6(1):77-81.PMID: 7204922
  8. Wu, K, Ahluwalia, R, Chinchalkar, SJ, et al. The Effect of Simulated Total Distal Interphalangeal Joint Stiffness on Grip Strength. Plast Surg (Oakv) 2018;26(3):160-164. PMID: 30148127
  9. Rozmaryn, LM. The Collateral Ligament of the Digits of the Hand: Anatomy, Physiology, Biomechanics, Injury, and Treatment. J Hand Surg Am 2017;42(11):904-915. PMID: 29101974
  10. Ootes, D, Lambers, KT and Ring, DC. The epidemiology of upper extremity injuries presenting to the emergency department in the United States. Hand (N Y) 2012;7(1):18-22. PMID: 23449400
  11. Adi, M, Hidalgo Diaz, JJ, Salazar Botero, S, et al. Results of conservative treatment of volar plate sprains of the proximal interphalangeal joint with and without avulsion fracture. Hand Surg Rehabil 2017;36(1):44-47.PMID: 28137442
  12. Wray, RC, Young, VL and Holtman, B. Proximal interphalangeal joint sprains. Plast Reconstr Surg 1984;74(1):101-7. PMID: 6739583
  13. Carlo, J, Dell, PC, Matthias, R, et al. Collateral Ligament Reconstruction of the Proximal Interphalangeal Joint. J Hand Surg Am 2016;41(1):129-32. PMID: 26614593
  14. Bot, AG, Bekkers, S, Herndon, JH, et al. Determinants of disability after proximal interphalangeal joint sprain or dislocation. Psychosomatics 2014;55(6):595-601. PMID: 25034813

Reviews

  1. Carruthers, KH, Skie, M and Jain, M. Jam Injuries of the Finger: Diagnosis and Management of Injuries to the Interphalangeal Joints Across Multiple Sports and Levels of Experience. Sports Health 2016;8(5):469-78.PMID: 27421747
  2. Rozmaryn, LM. The Collateral Ligament of the Digits of the Hand: Anatomy, Physiology, Biomechanics, Injury, and Treatment. J Hand Surg Am 2017;42(11):904-915. PMID: 29101974

Classics

  1. London PS. Sprains and fractures involving the interphalangeal joints. Hand1971;3(2):155-8. PMID: 5127923
  2. Shrewsbury MM, Johnson RK. Ligaments of the distal interphalangeal joint and the mallet position. J Hand Surg Am1980;5(3):214-6. PMID: 7400557