[Surgical correction of fifth finger permanent abduction by tenodesis. Preliminary cadaver study]

[Leprosy ulnar claw treated by Lasso Zancolli tendon transfer: report of a case]

La lèpre est une maladie infectieuse due à une mycobactérie (M. Leprae, Bacille de Hansen, ou BH) dont le tropisme nerveux est destructeur pour les cellules de Schwann. La localisation préférentielle des neuropathies tronculaire secondaire à la lèpre restent dominé par les zones ou les troncs nerveux traversent les défilés ostéo-ligamentaires inextensibles comme le défilé rétro-épitrochléen ou passe le nerf ulnaire. De nombreux travaux ont été consacrés à la souffrance nerveuse secondaire à la lèpre et surtout l'atteinte du nerf ulnaire qui se manifeste par une griffe des doigts. Le traitement dans ce cas est palliatif et fait appel à plusieurs techniques décrites dans la littérature. Nous rapportons dans ce travail un cas de griffe cubitale chez un patient lépreux traité par transfert tendineux de Lasso Zancolli.

[Permanent abduction of the little finger without ulnar nerve palsy: a case report]

Wartenberg's sign, or permanent abduction of the little finger, occurs in the context of sequelae of ulnar nerve palsy. Its presence alone is rarely reported in the literature and is due to avulsion of the insertion of the third volar interosseous muscle. Several surgical techniques to correct this sign are reported in the literature. The authors report the case of a Wartenberg's sign without ulnar nerve palsy due to traumatic avulsion of the third volar interosseous muscle that was treated by a transfer of the extensor digiti minimi onto the radial side of the extensor digitorium communis according to technique of Bellan et al. After 1-year follow-up, result was good with no recurrence of any deformities and a normal active extension.

Investigation of radialization and rerouting of the extensor digiti minimi (EDM) in the abduction deformity of the little finger: a cadaver study

BACKGROUND

One of several operations to correct abduction deformity of the little finger, (Wartenberg's sign) in ulnar nerve palsy, is a combined procedure that radializes the extensor digiti minimi (EDM) at the level of the fifth metacarpophalangeal (MCP) joint and reroutes it from the fifth to fourth extensor compartment. This cadaveric study was designed to investigate the impact of both elements on adduction.

MATERIALS AND METHODS

Anatomy of the little finger extensor apparatus was studied in 16 freshly frozen cadaver hands sectioned at mid forearm. We observed little finger motion after different modifications of the EDM. We tested the effect of a rerouting maneuver by pulling on the EDM, as well as radialization of the EDM alone and in combination with rerouting.

RESULTS

The EDM was present in all cases. Little finger extensor digitorum communis (EDC(V)) was missing in two cadavers. In no case was adduction created by rerouting the EDM to the fourth compartment. Radialization of the EDM corrected the abduction deformity beyond the axis of abduction/adduction of the fifth MCP joint in 13 cases and only up to it in three cases. In one of the three with limited correction, a rerouting maneuver allowed for further adduction.

CONCLUSION

The key to correct abduction deformity of the little finger is radialization of the EDM, which can be done through a solitary incision at the level of the MCP joint. Rerouting alone does not correct the abduction deformity, and in combination with radialization it does not predictably enhance the correction.

[Tenodesis in hand surgery]

Joining tendon's inextensibility with joint's mobility, a tenodesis fixes on the bones the two ends of a tendon on both sides of one or several joints. A "simple" tenodesis overrides only one joint, whereas a "dynamic" tenodesis crosses two or more joints. A "crossed" dynamic tenodesis crosses the line which joins rotation axes. A "direct" dynamic tenodesis is located on the same side of this line. The "tenodesis effect" is normally produced by the movements of the joint on the neighbouring tendons. Anatomical examples are given by the oblique retinacular ligaments (crossed dynamic tenodesis), and by the tenodesis effects linked to the flexion-extension of the wrist on the extrinsic tendons of the fingers (direct tenodesis effect), or to the flexion-extension of the PIP joints on the intrinsic tendons of the fingers (crossed tenodesis effect). Main tenodesis techniques are used for palliative surgery in paralysis of EDC, intrinsic muscles of the fingers, or extrinsic muscles of the thumb (EPL, FPL, APL and EPB).

Extensor indicis proprius transfer for the abducted small finger

PURPOSE

Persistent abduction of the small finger has usually been treated by transfer of the extensor digiti minimi muscle. However, anatomic variations of the extensor system may limit the potential for a successful extensor digiti minimi transfer. Therefore, we evaluated the outcomes of an alternative reconstruction method for the abducted small finger using an extensor indicis proprius (EIP) transfer.

METHODS

We performed 8 EIP transfers in 8 patients with persistent, flexible abduction posturing of the small finger. The primary etiology of the deformity was incomplete motor reinnervation after surgeries for ulnar neuropathy in 6 patients, rupture of the third palmar interosseous musculotendinous unit in 1 patient, and intrinsic muscle fibrosis in 1 patient. The EIP was elongated by splitting the tendinous portion and was transferred to the distal and radial part of the extensor hood. Surgical outcomes were assessed by comparing preoperative and postoperative active adduction and abduction motion of the 2 ulnar digits.

RESULTS

At the mean follow-up of 23 months, the average adduction angle improved from 19 degrees to 1 degrees postoperatively. In terms of active finger motion, 6 patients showed excellent results, 1 good, and 1 fair, without loss of flexion and extension. No patient had an extension lag or complained of functional deficits of the donor index finger. There was not adverse change to digital function or range of motion for the middle and ring fingers that are crossed by the EIP.

CONCLUSIONS

Extensor indicis proprius transfer can be a reliable option for correction of abduction deformity of the small finger, maintaining active abduction and full flexion and extension.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.