Dipartimento dellApparato Locomotore S C di Chirurgia della

Dipartimento dell’Apparato Locomotore S. C. di Chirurgia della Mano e Microchirurgia: Dir. Dr. A. Landi Azienda Ospedaliero-Universitaria Policlinico di Modena (ITALY) LESION IN CONTINUITY OF P. N. : COMPRESSION OF THE ULNAR NERVE A. Landi Responsabile servizio Archiviazione Informatica: M. Mancini 11 maggio 2010

COMPRESSION OF THE ULNAR NERVE

Ulnar Nerve Innervation Arises from the medial cord of the brachial plexus Roots C 7, C 8, T 1 Wrist and Hand • Abductor digiti minimi C 8, T 1 • Flexor digiti minimi C 8, T 1 • Lumbricales (3 rd and 4 th) C 8, T 1 • Flexor pollicis brevis (deep branch) C 8, T 1 • Adductor pollicus C 8, T 1

Ulnar Nerve Innervation Arises from the medial cord of the brachial plexus Roots C 7, C 8, T 1 Wrist and Hand • Opponens digiti minimi C 8, T 1

Ulnar Nerve Innervation Arises from the medial cord of the brachial plexus Roots C 7, C 8, T 1 Wrist and Hand • Interossei (palmar and dorsal) C 8, T 1

C 7 C 6 C 8 C 6 T 1 C 5 C 7 Assessment of injury to C 8 the roots of the brachial plexus or disruption of the spinal cord necessitates testing of dermatomes C 8 C 6 T 1 C 5

Anatomical variation on sensory distribution

Anatomical variation on motor distribution

How to assess the level of compression • Inspection • Palpation • The provocative manoeuvres • The sensory evaluations • The motor evaluations • The anatomical variations • The electrophysiological assessment • The Jamar and Pinch tests

Muscular evaluation (M 0 - M 5 grading system)

Ulnar Nerve Paralysis Wartemberg Sign Inability to adduct the extended little finger to the extended ring finger X

Grasp Strength Test

Pinch Strength Test

Sensory evaluation Semmes-Weinstein Monofilaments

ASSESSMENT OF THE UNDERLYING JOINT • The unstable MP Joint • The stiff claw hand

Compression of the ulnar nerve at the elbow Motor deficits: - FCU - FDP 4 th and 5 th - ulnar intrinsic - usually no claw-hand deformity - sensory deficit volar + dorsal aspect 4 th and 5 th finger

Cubital Tunnel Compression Symptoms: patient complains of hand weakness and numbness of the ring finger and small finger with a diminished sensory test both volar and dorsally

Compression of the ulnar nerve at the wrist Motor deficits: - ulnar intrinsic - claw-hand deformity - sensory deficit volar + dorsal aspect 4 th and 5 th finger

Guyon’s Canal Compression Symptoms: Sensory deficit in the volar aspect of the fifth digit and the ulnar side of the fourth, intrinsic muscle weakness Decreased pinch and grip strength with pain over volar wrist and fifth digit

Adjunctive investigations in the diagnosis of compressive syndromes of the ulnar nerve • X-rays: Cervical rib, malunions of the humerus, osteofytes, pseudotumoral uremic calcinosis, systemic sclerodermia… • Ultrasonography: Ganglions, Muscles… • MRI: Definitions of soft tissue tumours + MRI angiography • Electrophysiological investigations • Doppler: pseudoaneurism, thrombosis of the ulnar artery

Compression of the ulnar nerve at the elbow: indication for simple decompression • Absence of trauma on history • Absence of skeletal deformities • Absence of subluxation or frank dislocation of the nerve • Hyatropatic compressions following general anaesthesia

Diabetic neuropathy The compression of the median nerve at the wrist and the unlnar nerve at the elbow

Compression of the ulnar nerve at the elbow: indication to anterior transposition • Post-traumatic varus and valgus deformities • Subluxation or frank dislocation of the nerve • In association to oedematous neuropathies

Epiphiseal trauma of the throclea • Salter Type V • Varus deformity of the elbow Ulnar nerve compression Children: Vedge osteotomy Adult: Ulnar nerve transposition

Anterior traslocation of the ulnar nerve Surgical technique

Submuscolar transposition of the ulnar nerve • In presence of functional failures following previous surgery • In association with initial or hyatrogenic neuropathic conditions • In presence of a scarred bed

THE FASCIO- SEPTAL RELEASE

The painful conditions of the ulnar nerve • The neurodesis effect = inflammatory response = generation of ectopic impulses • The hyatropatic lesions a) Chemical injections b) Following coronaries by pass surgery c) Injury of the medial brachial and antibrachial cutaneous sensory branches* * I Sarris, F Goebel, M Gainer et Al. Medial brachial and antibrachial cutaneous nerve injuries: effect on outcome revision cubital tunnel surgery. Journal of Reconstructive microsurgery 18 (8): nov 2002

• Chemical lesion by local injection of reparil on the ulnar nerve at the elbow… • Complete motor and sensory recovery following external neurolysis but… unberable pain, the patient is placing the hand undfer a pillow and had to give up any avocational activities

The entrapment neuropaties at the elbow: Differential diagnosys beetwen • • The post traumatic compression The hyatropathic lesions The compression in tumoral conditions The compression in infectious diseases: lepromatous neuropathy

Elbow dislocation • Posterior dislocation might be associated to radial nerve palsy • Pure lateral elbow dislocation causes traction of the ulnar nerve, due to the integrity of the cubital tunnel • In postero lateral dislocation the ulnar nerve may escape to traction for the damage of the roof of the cubital tunnel

The dislocation of the medial epicondyle into the elbow joint • The medial epicondyle usually completes its maturation at 18 yrs of age • When the medial epicondyle is not visible on X-ray, following an elbow trauma, it might have been entrapted into the elbow joint, with consequences for joint functionality and with ulnar nerve entraptment

The foreign body reaction

Compression of the ulnar nerve in lipofibromatous hamartoma

Compression of the Ulnar Nerve at the wrist

Compression of the Ulnar Nerve in Guyon’s Canal Symptoms: Sensory deficit in the volar aspect of the fifth digit and the ulnar side of the fourth, intrinsic muscle weakness Decreased pinch and grip strength with pain over volar wrist and fifth digit

The Ulnar Nerve at the Wrist The dorsal cutaneous branch of the ulnar nerve comes off proximal to Guyon’s Canal therefore, dorsal sensory involvement of the 4 th and 5 th digit would indicate a problem proximal to the wrist. Ulnar nerve Dorsal digital branch Palmar cutaneous branch

COMPRESSION BY A GANGLION

The vascular lesions in association to the ulnar nerve compression at the wrist with no vascular related symptoms

The vascular lesions in association to the ulnar nerve compression at the wrist with vascular related symptoms

Compression of the dorsal coutaneous branch* * JAI Grossman, I Yen, D Rapaport: The dorsal cutaneous branch of the ulnar nerve. Annales de la chirurgie de la main 1998 (17) 2

Ulnar Nerve Paralysis Classification of Distal Ulnar Nerve Compression Type I = both motor and sensory branches proximal to the wrist Type II = involves only the motor branch at the hook of the hamate and at the distal part of the canal Type III = involves only the superficial volar sensory branch

The entrapment neuropaties at the wirst: Differential diagnosys beetwen The post-traumatic compression The stiff claw-hand deformity

The ulnar nerve within the double crush syndromes • The Cervical cord compression and osteoarthryties of the cervical spine • Thoracic outlet syndrome: a) Clinical assessment b) Adjunctive investigations - MRI: (Scalenic space) - F-wave - SEPs - Magnetic stimulation of the brain

The clinical sign of the double crush syndrome

Differential Diagnosis • Amyotrofic Lateral Sclerosis • M. N. D. • The Thoracic Outlet syndrome • The pseudoclaw by muscle sarcoidosis • The psycotic hand

Paralisi dell’abduttore breve ed opponente del pollice provocato dal margine anteriore tagliente dello scaleno medio By curtesy of dr P. Raimondi

TPI Paralisi degli intrinseci tenari e ”griffe”ulnare provocata da marcata compressione-frizione del tronco primario inferiore davanti al margine anteriore dello scaleno medio By curtesy of dr P. Raimondi *

Conclusions • The level of compression of the ulnar nerve (be aware of the anatomical variations) • The multiple sites of compression • The priority of distal decompression • The different aetiologies • The exclusion of the different D. D. • Treatment tailored on individual basis