- combined injuries of the median and ulnar nerves:
- nerve repair
- median nerve repair at the wrist
- patient's ability to oppose is weak, and the FPL provides most of the strength in flexion;
- loss of the radial two lumbricals is not clinically significant;
- opposition is attempted but cannot be done because of atrophy of the opponens and APB;
- thumb abduction strength will decrease on average by 70%, but in some cases losses will not be this severe if there is retention of function of FPB;
- thumb may remain supinated;
- in general, 1/3 of patients do not need opponensplasty since adequate thumb abduction is gained from other muscles;
- "opponens symptom:"
- based on the observation that loss of the opponens muscle function, the EPL and the EPB cannot fully extend the thumb MP joint;
- it is due to the integral functional relationship between the EPL and the opponens muscle;
- Prerequisites for tendon transfers:
- strong FPL and a strong EPL;
- absence of wide web space;
- adequate thumb sensation;
- stable metacarpophalangeal joint (w/ adequate extension) (if this is not case, then consider a concomitant MP fusion);
- stable pulley in region of the pisiform bone;
- strong motor for transfer;
- normal function of the FDS (if this is considered for transfer);
- polyneuropathy: (AML, MS, or Charcot Marie Tooth);
- consider ECRL opponenplasty or palmaris longus opponenplasty rather than opponenplasty w/ a more distal and weaker motor;
- with any attempted opponensplasty, it is important the the transfer lie in the direction of the APB;
- Camitiz Procedure:
- PL (and its palmar fascia) are transferred to the APB;
- consider passing the palmaris longus underneath the APB aponeurotic origin (on the carpal fascia) inorder to take advantage of a pulley effect
and attain a better abduction moment;
- the tendon is then passed distally and attached to the radial collateral ligament;
- this procedure should be considered in any adult undergoing a median nerve repair (the transfer acts as an internal splint)
Restoration of strong opposition after median-nerve or brachial plexus paralysis.
Abductor digiti quinti opponensplasty.
Tendon transfer for median and ulnar nerve paralysis.
The effects of low median nerve block on thumb abduction strength.
Immediate Camitz opponensplasty in acute thenar muscle injury.
Palmaris longus tendon transfer for augmentation of the thenar musculature in low median palsy.
Opponensplasty using palmaris longus tendon and flexor retinaculum pulley in patients with severe carpal tunnel syndrome