A Fun Fact from a Hand Therapy Student

By: Ammie Ingwaldson

Level 2 Fieldwork at a hand therapy clinic is a fast paced and continuous learning experience. The perfect example of this occurred last week while observing a therapist provide a client with their home CMC arthritis program.  The therapist was educating the client on how to oppose their thumb to their small finger. While we watched them practice, she stated, “you have the Linburg sign!” She quickly turned to me and had me oppose my thumb to the base of my small finger, then confirmed that I had it as well. I began to become slightly concerned. We had not reviewed this sign or condition in school. I began to wonder if it was treatable and if it would affect me. My worries were put at bay when she then showed that she had it as well and provided an explanation of what it entailed.  

linburg comstock syndrome

Linburg Comstock syndrome is an anatomical anomaly connecting the tendons of flexor digitorum profundus (FDP) of the index finger and flexor policis longus (FPL) (Puroshothaman & Powers, 2008). This connection of tendons leads to involuntary flexion of the index finger at the distal interphalangeal (DIP) joint with flexion of the interphalangeal (IP) joint of the thumb. The incidence of this anomaly is 37%, with higher distribution of unilateral sign than bilateral.

linburg comstock syndrome

In most cases Linburg-Comstock syndrome is asymptomatic, but it can present as pain in the distal forearm, wrist, or hand. Median nerve symptoms, similar to carpal tunnel, can also be present due to tendon inflammation, presence of additional tendons, or synovitis with in the carpal tunnel (Puroshothaman & Powers, 2008). Individuals with repetitive thumb and finger movements, such as musicians, are more susceptible to pain or carpal tunnel like symptoms. Surgical release of the connection of FPL and FDP can be performed to relieve symptoms (Old, Rajaratnam & Allen, 2010). 

References

Old, O., Rajaratnam, V., & Allen, G. (2010). Traumatic correction of Linburg-Comstock anomaly: a case report. Annals of the Royal College of Surgeons of England, 92(4), W1–W3. doi:10.1308/147870810X12659688852031

Puroshothaman, P., & Powers, D. (2008) A simple diagnostic test for symptomatic Linburg-Comstock anomaly (Linburg-Comstock test). The Internet Journal of Hand Surgery, 2(2), 1-3. 

3 Comments

  1. V. Jackson on January 31, 2020 at 9:03 am

    I love that great fun fact with a quick explanation, great visual representation of the UE possible problems, and treatment options that are available.

    Thanks.

  2. spencer on January 24, 2023 at 2:14 pm

    I have this issue but not just one or two fingers is every finger in both hands. if i bend thumb even my little finger goes with it. Just wondering how rare it is for that to happen?

  3. Sammie on January 14, 2026 at 1:51 pm

    Thanks for sharing! Funny enough, I also found out I had this anomaly during my level 1 OT fieldwork rotation at a hand therapy clinic! Actually, I realized I had this involuntary flexion of the index finger when I was young, in girl scouts, and I was unable to do the girl scout hand sign without my pointer finger bending. I forgot about it until my fieldwork rotation, where I found out the name of what it was and why it occurs! So, I guess another clinical test option could be to have the client try to do the girl scout hand sign 😂

Leave a Comment






More To Read

A Better De Quervain’s Tenosynovitis Test

November 10, 2019

J. F. Goubau, L. Goubau, A. Van Tongel, P. Van Hoonacker, D. Kerckhove, B. Berghs (2013).The wrist hyperflexion and abduction of the thumb (WHAT) test: a more specific and sensitive test to diagnose de Quervain tenosynovitis than the Eichhoff’s Test. J Hand Surg Eur Vol. 2014 Mar; 39(3): 286–292. Published online 2013 Jan 22. doi:…

Splinting and Stretch Protocol for Pediatric Trigger Thumb

May 10, 2020

Tan, A. C., Lam, K. S., & Lee, E. H. (2002). The Treatment Outcome of Trigger Thumb in Children. Journal of Pediatric Orthopaedics B, 11(3), 256-259. The Skinny:Pediatric trigger thumb is a “relatively uncommon” condition of unknown origins. Studies have indicated that spontaneous recovery of trigger thumb is around 25-40%, and chances increase with age.…

Differentiating Proximal Median Nerve Entrapment from Carpal Tunnel Syndrome

August 9, 2020

By: Brittany Day Proximal Median Nerve Entrapment, Pronator Syndrome, or Lacertus Syndrome?  Pronator syndrome is a term used to describe proximal median nerve entrapment (PMNE) in the forearm. Pronator syndrome and lacertus syndrome are sometimes used interchangeably to describe proximal median nerve entrapment distal to the ligament of Struthers and proximal to the flexor superficialis…

Video Augmented Hand Therapy after CVA with hemiplegia.

September 9, 2023

The previous rapid review discussed the positive outcomes of video-augmented hand therapy after a CVA with hemiplegia. Please watch this vlog to discover how to make the video augmented box to make it easily integrated into your clinic. Video By: Shannon Skowbo

Envelope_1

Sign-up to Get Updates Straight to Your Inbox!

Sign up with us and we will send you regular blog posts on everything hand therapy, notices every time we upload new videos and tutorials, along with handout, protocols, and other useful information.