In thumb hypoplasia, classified by Blauth, all these statements are true except:
The standard management of Blauth 4 is reinforcement of the hypoplastic thumb by bone stabilisation and tendon transfer. This statement is incorrect; the standard management of Blauth 4 is NOT reinforcement of the hypoplastic thumb by bone stabilisation and tendon transfer. Blauth 1 describes a mildly hypoplastic thumb with hypoplastic or absent short thenar muscles. Opposition is weak or absent. Blauth 2 often includes laxity of the MCP joint and the ulnar collateral ligament requires reinforcement. Blauth 3 contains a variable development of the CMC joint. In essence, a good CMC joint leaves a potentially useful thumb, capable of reinforcement by tendon transfers; a poor CMC joint is likely to dictate a pollicisation. Blauth 4 describes the ‘pouce flottant’ or floating thumb. This is generally of no functional use and standard management includes its removal and a pollicisation. Blauth 5 describes total absence of the thumb with variable associated anomalies of the entire radial ray.
In the finger, what is the usual relationship of the digital nerve to the digital artery?
Volar. In the digit the digital nerves usually lie medial and slightly volar to the digital arteries.
Contraindications to early exploration in brachial plexus injury include:
Absence of a Tinel’s sign in the supraclavicular fossa. The following is a contraindication to early exploration in brachial plexus injury. There are advocates for immediate exploration of brachial plexus injuries and also advocates for delayed exploration. When there is a strong suspicion of root avulsion and nerve rupture, surgical exploration is without doubt warranted at an early stage. Horner’s syndrome is strongly correlated with avulsion of C8/T1 roots. It is a poor prognostic sign for spontaneous recovery. Presence of a Tinel’s sign in the supraclavicular region indicates a post-ganglionic injury, and thus a possibility of recovery. Absence of a Tinel’s sign may indicate a preganglionic injury and thus is a bad prognostic sign indicating early exploration. The presence of a pseudomeningocele on MRI indicates root avulsion and again is a factor indicating early exploration. Fracture of the first rib and injury caused by gunshot are both high-energy injuries that would indicate significant trauma to the plexus and again warrant early exploration.
In older patients with traumatic amputation of the thumb, when you perform a pollicisation, surgical intervention differs from young children with congenital absent thumbs in that:
In traumatic cases of older patients it is necessary to shorten the flexor tendons. When pollicisation is performed in children at the age of 6 months, only the extensor mechanism needs to be tightened. As the child grows, doubling in size over the next 6 months, the flexor tendons become active without the need for surgery. This avoids surgery to the flexors and resultant scarring. In older children, the growth is not so remarkably fast and it is necessary to shorten the flexor mechanism during the surgery for pollicisation since the child is also more dependent on the use of both hands than the infant.
References:
1. Scheker LR, Cendales LC. Correcting congenital thumb anomalies in children: opponensplasty and pollicization. In: The growing hand: diagnosis and management of the upper extremity in children. Gupta A, Kay SPJ, Scheker LR. St. Louis, USA: Mosby, 2000: 171-82.
Toe-to-hand transfer in patients with bilateral hands affected with constriction ring syndrome:
Should be performed in cases of painful tip of the digits to provide padding to the end of the digits and required length. Children with constriction ring syndrome often have multiple digits involved and therefore a cross finger flap is not an option. Toe-to-hand transfer brings not only length but sensation and a stable tip and is especially important in cases in which the tip of a particular finger is painful with an ischaemic tip because of skin shortage.
Toe-to-hand transfer is a well-established reconstructive option for certain congenital hand anomalies 1. It is the only technique which can add growth potential to the immature skeleton. Toe transfer is best suited for constriction ring amputations, which have relatively normal proximal anatomy. Transfers should be performed early in life to avoid lack of cortical integration of the new part. Anatomic variations of both hand and foot are often encountered, which influence both operative approach and functional prognosis. Constriction ring syndrome is classified by Patterson into: I - a simple band; II - a construction band with distal lymphoedema; III - with acrosyndactyly; and IV - congenital amputation.
References: 1. Eaton CJ, Lister, GD. Toe transfer for congenital hand defects. Microsurgery 1991; 12(3): 186-95.
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