Diagnostic and Therapeutic Standing Needle Arthroscopy of the Distal Interphalangeal Joint in 36 Horses.

Overview

• This study evaluated the use of a minimally invasive needle arthroscopy technique performed on standing horses to diagnose and treat joint issues in the distal interphalangeal joint (DIPJ).
• The research describes the procedure’s technique, effectiveness, complications, and short-term outcomes in both cadaver limbs and live clinical cases.

Introduction and Study Purpose

• The distal interphalangeal joint (DIPJ) in horses is a common site for lameness and joint disease.
• Traditional arthroscopy often requires general anesthesia, which carries risks, so there is interest in minimally invasive procedures performed on standing horses under sedation.
• This study aimed to describe and evaluate the safety, feasibility, and outcomes of standing needle arthroscopy using a very small (1.9-mm) arthroscope for both diagnostic and therapeutic purposes in the DIPJ.

Study Design and Methods

• This was a retrospective study involving two parts: initial testing on five cadaver forelimbs and subsequent clinical application on 36 client-owned horses.
• In all procedures, a 1.9-mm needle arthroscope was utilized to visualize the DIPJ anatomy through dorsal and palmar joint recesses.
• The horses underwent the arthroscopy under standing sedation combined with local anesthesia to avoid general anesthesia complications.
• Data recorded comprised:
  • Signalment (age, breed, sex) of horses
  • Diagnostic imaging findings prior to arthroscopy
  • Intraoperative observations such as cartilage defects, capsular tears, or osteochondral fragments
  • Complications during or after the procedure including bleeding and infections
  • Clinical outcomes reported up to 12 weeks post-procedure

Results

• In cadaver limbs:
  • Arthroscopy was successfully completed in all five forelimbs.
  • Consistent and clear visualization of joint anatomical landmarks was achieved from both dorsal and palmar approaches.
• In live clinical cases involving 36 horses:
  • 12 underwent therapeutic arthroscopy for removal of osteochondral fragments.
  • 24 were evaluated diagnostically to better understand lameness causes.
  • Common findings included cartilage defects and capsular tears within the DIPJ.
  • Osteochondral fragment removal was successfully done in all indicated cases.
  • Complications were mild and limited mainly to intra-articular bleeding categorized as:
    • 15 mild cases
    • 4 moderate cases
  • No infections or serious adverse events were reported at any time.
  • All horses recovered uneventfully and were discharged without complications.
  • At 12-week follow-up, no further complications were noted.

Conclusions and Clinical Implications

• Standing needle arthroscopy of the DIPJ is a safe and effective minimally invasive technique providing both diagnostic and therapeutic benefits.
• This method significantly reduces risks related to general anesthesia since horses remain standing and sedated.
• The small diameter needle arthroscope allows excellent visualization of joint structures and accurate treatment interventions such as fragment removal.
• Minor complications like mild bleeding occur but are manageable and do not compromise outcomes.
• This procedure appears to be a valuable tool for equine veterinarians dealing with DIPJ pathologies, offering quicker recovery and less risk compared to traditional arthroscopy under anesthesia.
• Further studies may focus on long-term outcomes and comparisons with other diagnostic and treatment modalities.