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Fritz de Quervain descibed in 1895 a painful condition that affected the wrist and thumb. Technically this used to be known as stenosing tenovaginitis and consists of a constriction at the exit from their sheath, of two of the tendons to the thumb. These two tendons of abductor pollicis longus and extensor pollicis brevis course from the upper forearm, around the thumb side of the wrist and up onto the back of the thumb. They are held against the side of the radius in a sheath (known as the first extensor compartment). Whilst initially there may be some inflammation there certainly is none when it is chronic which is why the NSAIDS do not work very well.
There are a number of anatomical variations of the internal structure of this compartment which are not relevant clinically but are critical when it comes to surgery. The condition can be precipitated by activities that involve a lot of opening out of the thumb coupled with a lot of movement of the wrist, especially ulnar deviation.
It is more common in women and has a peak incidence in the 40s and 50s though it affects a steady number of mothers in the post-partum period. Fortunately for this group of patients the condition can spontaneously resolve. The mainstays of initial treatment are rest, avoidance of the precipitating activity, use of a splint, physiotherapy and a cortisone injection (best performed under ultrasound scan guidance). It is preferable for these treatment modalities to occur in the order presented but if all else fails then surgery becomes an option.
The operation to surgically relieve De Quervain's stenosis has somewhat of a notorious reputation as there have been poor results reported in the past. With an absolute understanding of the anatomy, the operation is safe and the results more predictable. The two critical surgical issues that must be addressed are firstly, the variations in the internal anatomy of the extensor compartment and secondly the fact that overlying the sheath are several fine branches of the superficial radial cutaneous nerve (please see the picture above). If these fine nerves are damaged they can give rise to a very sensitive neuroma which can be extremely difficult to treat and can be worse than the original condition. By taking meticulous care in the dissection and approach to release the sheath, the risks to the nerve branches are reduced to an absolute minimum. However, they can still be sensitive to careful handling and there is still a risk of some altered sensation on the back of the hand especially between the thumb and the index finger. I am not aware of ever having caused a neuroma but have seen the problem of altered sensation (less than 5% incidence).
The wound is sutured with dissolvable stitches and steristrips and the wrist and thumb bandaged with a non-waterproof dressing. This stays on for a week, when it can be reduced to dressing and more vigorous activities commenced. Driving is not advisable in the first week but you may be safe in the second week. It is sensible to plan on about one month of restricted activites to allow the area to heal and strengthen.