Date post: | 24-Jul-2015 |
Category: |
Health & Medicine |
Upload: | alberto-mantovani |
View: | 763 times |
Download: | 4 times |
Purpose We have developed a system of percutaneous fixation of unstable distal radius fractures (UDRF) using 4 Kirschner (K) wires without plaster support (1). These K wires are passed from the lateral side of the radius and connected and locked among themselves using a modified clamp* described by B. Joshi. We call this “Legnago Technique” or Percutaneous Lateral Locked Pinning (PLLP). The intention of this study is to standardize the method and make it safe and easily reproducible.
Ori
gin
al J
osh
i cla
mp
modified Joshi clamps * of Economico ® Medriver
external fixator
The indications were stricly limited to the UDRF type A2 and A3 of the AO classification, excluding the A3.3 and to the Salter Harris type 2 or metaphyseal fractures in children. Instability was evaluated according to Mackenney et al. criteria (2).
Indications
We treated 32 adult patients aged from 45 to 101, 5 men and 27 women, 11 children aged from 7 to 17, 4 girls and 7 boys (total 43 cases) between 2009 and 2011. Each patient was evaluated according to Mayo Wrist Score criteria, with a follow-up ranging from 6-24 months. The distal radius-ulnar index and the radial and volar tilt were measured on radiographs after the procedures and after consolidation.
Methods
These were usually emergency procedures, performed under local anaesthesia and under image intensifier control. We recommend a small incision at the entry point of each K wire and blunt dissection up to the bone in order to avoid impalement of vessels, tendons or nerves. We follow a standard sequence of passing wires, starting with a 2 mm K wire from the radial styloid into the medullary canal of the radius. This is inserted dorsal to the tendons of the first extensor compartment. The K wire was mounted on a Jacob’s chuck handle and was pre-bent at its leading end to around 30 degrees. This helps to control the direction of the wire within the bone and, also, helps in achieving the reduction by “three-point pressure” effect. The subsequents 3 K wires ø 1.8 (1.6) mm, are inserted across the fracture using a motorized drill in multiplanar configuration. Finally all the K wires are bent adequately in a convergent direction along the axis of the wrist on the lateral side and locked together into a modified Joshi clamp. No splint or plaster support has been used.
Technique
The K wire 1 & 2 are inserted dorsal of the first extensor compartment pulley (P) in the “bare area” between divergent first and second compartment . The subsequent 3 & 4 K wire are inserted between the brachioradialis (BR) and extensor carpi radialis longus (ECRL) tendons. The superficial branch of the radial nerve (SBRN) emerge between BR and ECRL at 7~9 cm from the Qp of the radial styloid and bifurcates at ~5 cm.
Entry points of the K wires in the fractured radius (F)
Modified Joshi clamp
Results We noted 14 excellent results, 7 good and 3 satisfactory. Radiological consolidation of the fracture was achieved in each patient, at an average delay of 40 days. Union occurred with no change in the radiological parameters achieved by the operation. The complications included 3 cases of superficial infection around the K wires and a partial lesion of the superficial radial nerve. The patients regained complete autonomy in the use of the affected upper limb for activities of daily living within a week from the operation. None of the patients underwent supervised physiotherapy. All patients were encouraged to mobilize their wrist immediately
Conclusions The Legnago technique has proved efficacious in the treatment of unstable extra-articular fractures. The particular arrangement of multiplanar insertion of the K wires and their connection and locking using an external fixator clamp allowed early active mobilisation of the wrist without plaster support. This concurs with recent experimental demonstrations according to which the biomechanical stability of the percutaneous fixation of the UDRF with externally connected crossig K wires is superimposable to that obtained by volar locked plates (3).
Instruments
Landmarks Pin track block
Haematoma block
2 1 3 Intramedullary reducQon by “three-‐point pressure” effect.
MulQplanar and
Transfocal pinning
Bent and locking of K wires
First manual bent of K wires
Second convergent bent of K wires with mechanical pliers and locking into a modified Joshi clamp
2
3
4
Blunt dissection
Blunt dissection
1. Mantovani A, Trevisan M, Carle4 D, Cassini M Pinning percutaneo laterale bloccato delle fra>ure extra ar@colari instabili del radio distale: Tecnica di Legnago. Riv Chir Mano 2012; 49(3): 1-‐11. 2. Mackenney PJ, McQueenn MM, Elton R. Predic@on of instability in distal radial fractures. J Bone Joint Surg Am 2006; 88 (9): 1944-‐51. 3. Strauss EJ, Banerjee D, Kummer FJ et al. Evalua@on of a novel, non spanning external fixator for treatment of unstable extra-‐ar@cular fractures of the distal radius: biomechanical comparision with a volar locking plate. J Trauma 2008; 64: 975-‐981.
References
Email:: [email protected]
1st K wire ⌀ 2 mm Intramedullary reducQon with a Jacob’s chuck handle: “three-‐point pressure” effect.
2nd, 3th, 4th K wire ⌀ 1.8 (1.6) mm MulQplanar and Transfocal Pinning with motorized drill