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Question:

Describe this picture and what condition it is associated with

Carpal Tunnel Syndrome - Orthopaedic Surgeon - Shoulder and Upper ...

CTS

Most common compressive neuropathy – median nerve underneath the transverse carpal ligament

9 tendons and 1 nerve

Palmar cutaneous branch comes off 5cm proximal to wrist crease

Recurrent motor branch has variable anatomy to supply LOAF muscles (see below) Kaplans Line Ulnar border of thumb 1 and 2nd web space

Multiple causes

idiopathic / physiological / mass effect / systemic illness / inflammatory

Typical symptoms – nocturnal pins and needles, dropping things

Signs – look – wasting thenar muscles

– feel – sensation decreased tips of thumb and index

– move – test (ABPB)

– sp. tests – Tinels / Phalens / Durkins

Diff

Pronator Syndrome – also look forearm muscles wasting / sensation palm of hand / pain on resisted pronation

C6 radicuopathy – test wrist extension / sensation lateral border forearm

CMCJ OA – tenderness over base of thumb / +ve grind test

Confirm with NCS (if doubt)

Motor – prodromically / stimulus electrode placed proximal to CT and recording electrode placed on AbPB muscle (+ indifference and ground electrodes on other fingers)

Positive if  – increased latency >4ms / decreased amplitude <5mv

Management

Non operative – info sheet / night splint

Diagnostic injection 2mls 0.5% marcaine and 40 mgs depomed (2cm proximal wrist crease and ulnar to PL tendon) – use if clinically a bit equivocal and NCS normal (does happen)

Operative (see above)

Open release gold standard – 90% success

Grip strength 3/12 to return

Beware scar tenderness / pain

J Hand Surg [Am]. 1998 Sep;23(5):852-8

Answer

Describe how you would do a carpal tunnel release

Answer:

Marked and consented

Patient supine / arm table – local anaesthetic 10mls 1% lignocaine infiltrated with blue needle – field block

High arm tourniquet but more pleasant for the patient if one is not used – explain to patient

Loope magnification

Prep and drape

Check the local anaesthetic

Longitudinal incision in line with radial border of ring finger just ulna to prominent crease – no further distally than Kaplan’s cardinal line

Down through skin and subcutaneous tissue

3 by 4 pronged self retaining retractor in – key to operation is to keep tension on tissues

Cut with sharp dissection through the transverse carpal ligament

When the carpal tunnel is reached use a MacDonald underneath to protect the median nerve and open it up

Use scissors distally

Use MacDonald and blade proximally to complete release

Check median nerve is free

Close with 4,0 vicryl rapide interrupted sutures, mepofix dressing and crepe bandage

Elevate

Answer

Please discuss the anatomy of the recurrent branch of the median nerve

The anatomy of the recurrent branch of the median nerve.

Kozin SH.

101 cadavers disected to spatially define the origin and course of the recurrent branch of the median nerve

The recurrent branch of the median nerve was classified into 3 types.

Type I passed through the TCL; it is rare, occurring in 7% of the specimens.

Type II nerves (74%) passed distal to the TCL through separate obliquely oriented fascia that originated on the TCL and inserted on the undersurface of the palmar aponeurosis.

Type 111 (19%) passed distal to the TCL, but did not pass through the obliquely oriented fascia.

99% originated either from the central portion of the median nerve or just radial to it. There were no ulnar origins.

4% had more than 1 recurrent branch.

The variability in the literature on the anatomy of the recurrent branch can be accounted for by failure to properly identify the TCL as being separate from the obliquely oriented fascia distal to the TCL through which the nerve frequently penetrates.

This study concludes that the transligamentous branch (type I) is uncommon and the reported high incidence of branches passing through the TCL can be explained by mistakenly combining recurrent nerve types I and II.

Answer