Double Crush of Ulnar Nerve
Jean Paul Brutus MD
Exception MD, Optimist, Minimally Invasive Hand Surgery Expert, WALANT surgeon, Patient Experience advocate
Great Question by Marvin Chung : How do you diagnose Double Entrapment of the Ulnar Nerve at the Elbow and Wrist?
Here is my answer. I hope this helps.
Cubital tunnel Syndrome: very frequent
Frequent complaints are: tingling and numbness in small and ring fingers, elbow pain, less commonly decreased grip power
Physical Examination: Sensation is often decreased in ulnar side of the hand, including in the territory of the dorsal branch of the ulnar nerve. Flexion of the elbow and extension of the wrist increase symptoms, Positive Tinel or compression of ulnar nerve at the elbow is tender (usually at the inlet of the FCU aponeurosis), Flexor Carpi Ulnaris is weak, FDP D5 is weak. Sometimes, claw deformity of the hand and possible atrophy of the intrinsic muscles.
Scratch Collapse test positive over the cubital tunnel but negative over Guyon's canal. Cold spray test confirmation by turning the positive SCT into a negative.
Guyon's canal entrapment: rare
Frequent complaints are: Weakness of the hand, clumsiness, and decreased dexterity. Possible numbness and tingling in small and ring fingers but not on the back of the hand. Wrist pain.
Physical Examination: Sensation can be decreased in the ulnar nerve territory, excluding dorsal hand. Muscle atrophy and often flattened appearance of the hand. Sensory symptoms not made worse by flexion of the elbow. FCU and FDPD5 are not weak. Abductor Digiti Minimi is weak. Scratch Collapse Test is positive over Guyon's canal but not the elbow. Cold Spray test will confirm dx by turning the positive SCT into a negative one.
Double Entrapment of the ulnar nerve at both Elbow and Wrist: rare
Symptoms and physical examination findings are combined.
Tingling and numbness in ulnar side of the hand, including back of the hand.
Symptoms made worse by flexion of the elbow and extension of the wrist.
Weak FCU, FDPD5 and Abductor Digiti Minimi
Flat hand
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Possible Claw deformity
Positive Scratch Collapse Test over Cubital Tunnel and Guyon's canal.
Cold spray test confirmation at both sites.
Treatment if conservative treatment fails: Staged or Combined (my preference) release under Walant. Concurrent treatment of underlying cause in Guyon's canal if indicated.
Immediate (on the table) return of power to FCU, FDP D5, ADM (with active cooperation of the unsedated and fully awake patient) confirms adequate release of both sites.
Elisabet Hagert, MD PhD Donald Lalonde Amir Adham Ahmad Edward de Keating-hart Dr. Rodney French Alejandro Badia, MD Brian Jurbala M.D.~ FAAOS, CAQSM, CAQSH Orthopaedic Surgeon- Ortho~Hand~Sports Med. Dott. Loris Pegoli Nicolas Dreant Alison TAYLOR Kevin Kruse Benjamin Ferembach Thomas APARD
Certified Hand Therapist, Occupational Therapist, Online Entrepreneur
1yJean Paul Brutus MD how would you differentiate the double crush from a compression further proximal, i.e. thoracic outlet syndrome? I assume the answer is scratch collapses test? Do you do it at the scalene triangle?
Orthopaedic Surgeon | Clinical Assistant Professor at HKUMed
1yThanks! Helpful article. To me making the diagnosis of cubital tunnel syndrome is not difficult, but it is difficult to know whether there is concurrent compression at the Guyon’s canal, since the physical findings of motor & sensory overlaps with the proximal compression. And nerve conduction study is often not very helpful either. So the key is to perform SCT with cold spray confirmation at both sites, am I correct?
Sports Medicine Surgeon and Upper limb trauma surgeon. Shoulder and Elbow Surgery Fellow at University College London Hospitals
1yDoes claw deformity incline you towards the Guyon’s rather than Ulnar tunnel? Thank you
Exception MD, Optimist, Minimally Invasive Hand Surgery Expert, WALANT surgeon, Patient Experience advocate
1yMarvin Chung