Surgical technique: about a new total and isoelastic wrist implant (Prosthelast®).

This study describes a new total wrist implant (Prosthelast®) designed to reduce the risk of distal migration of the carpal component. The Prosthelast® implant consists in a one-block radial implant replacing the metaphysis and the articular surface fixed to a radial elastic centromedullar wire and a carpal component in titanium with an articular condylar surface in polyethylene. We operated on five patients (three male patients and two female patients) and followed them up for 12 months on average. Two of the patients presented with rheumatoid arthritis of the wrist, and an ulnar osteotomy (Darrach procedure) was carried out at the same time of the arthroplasty. All clinical variables improved postoperatively (Quick DASH score, pain score, range of motion) except from wrist flexion which was reduced. No patients underwent revision surgery. Two patients presented with a periprosthetic radiolucent loosening around the radial component, but no implant migration was observed. Overall, the preliminary results of our case series show that the new Prosthelast® implant presents comparable short-term results to those described in the literature. We will follow up the patients to verify that long-term results are as satisfactory as the short-term results.

Carpal scaphoid non-union treatment: a retrospective trial comparing simple retrograde percutaneous screw fixation versus percutaneous screw fixation plus pulsed electromagnetic fields (Physiostim®).

BACKGROUND: The purpose of this retrospective comparative study was to assess whether a complementary treatment by pulsed electromagnetic field could increase the bone-healing rate of scaphoid non-union without SNAC (scaphoid non-union advanced collapse) treated by retrograde percutaneous screw fixation. CASE DESCRIPTION: Eighteen patients with scaphoid non-union were included in this retrospective study. The group 1 was made of nine cases (seven stage IIA and two stage IIB) of scaphoid non-union treated by retrograde percutaneous screw fixation and pulsed electromagnetic fields (Physiostim®). The group 2 was made of nine cases (six stage IIA and three stage IIB) treated by simple retrograde percutaneous screw fixation. RESULTS: With a 10-month follow-up in group 1 and a 9.5-month follow-up in group 2, there were three cases of non-union in group 1 and two cases in group 2. Regarding the type of non-union, there was one case among the stage IIB and four cases among the stage IIA. CLINICAL RELEVANCE: The results of the study did not show any interest in the use of pulsed electromagnetic field for the treatment of carpal scaphoid non-union. They should be dropped. LEVEL OF EVIDENCE: III.

Long Volar Plating for Metadiaphyseal Fractures of Distal Radius: Study Comparing Minimally Invasive Plate Osteosynthesis versus Conventional Approach.

Background Minimally invasive plate osteosynthesis (MIPO) has been used in wrist surgery for several years. The purpose of this retrospective study was to compare clinical and radiologic outcomes of MIPO technique with those of a conventional approach in the treatment of metadiaphyseal distal radius fracture by long volar plating. Materials and Methods Our series consisted of 32 fractures in 31 patients, mean age 63.9 years, including 16 men and 15 women. MIPO technique was used in 15 wrists (group 1) and conventional approach (> 60 mm of skin incision) in 17 wrists (group 2). In group 1, a long volar plate was inserted under pronator quadratus through a 15- to 30-mm distal incision then fixed to the epiphysis of the distal radius. Then, through a 15- to 30-mm proximal incision, the plate was fixed to the diaphysis of the radius, thus reducing the fracture. Results In group 1, mean distal incision size was 23.5 and 16.9 mm for proximal one. Mean total scar size (sum of both distal and proximal incisions) was 40.0 mm in group 1 and 84.1 mm in group 2. Mean tourniquet time was 58.4 minutes in group 1 and 68.9 minutes in group 2. At latest follow-up, no significant difference was noted in both the groups concerning pain, quick-DASH score, grip strength, ROM, and radiologic data. One extensor pollicis longus rupture treated by tendon transfer was done in group 1. Conclusion The MIPO technique for metadiaphyseal fractures of the distal radius by long volar plating has cosmetic and economic advantages compared with the conventional approach. Conversion to conventional approach is possible at any time in case of technical difficulties. Level of Evidence III.

Review of Acute Traumatic Closed Mallet Finger Injuries in Adults.

In adults, mallet finger is a traumatic zone I lesion of the extensor tendon with either tendon rupture or bony avulsion at the base of the distal phalanx. High-energy mechanisms of injury generally occur in young men, whereas lower energy mechanisms are observed in elderly women. The mechanism of injury is an axial load applied to a straight digit tip, which is then followed by passive extreme distal interphalangeal joint (DIPJ) hyperextension or hyperflexion. Mallet finger is diagnosed clinically, but an X-ray should always be performed. Tubiana's classification takes into account the size of the bony articular fragment and DIPJ subluxation. We propose to stage subluxated fractures as stage III if the subluxation is reducible with a splint and as stage IV if not. Left untreated, mallet finger becomes chronic and leads to a swan-neck deformity and DIPJ osteoarthritis. The goal of treatment is to restore active DIPJ extension. The results of a six- to eight-week conservative course of treatment with a DIPJ splint in slight hyperextension for tendon lesions or straight for bony avulsions depends on patient compliance. Surgical treatments vary in terms of the approach, the reduction technique, and the means of fixation. The risks involved are stiffness, septic arthritis, and osteoarthritis. Given the lack of consensus regarding indications for treatment, we propose to treat all cases of mallet finger with a dorsal glued splint except for stage IV mallet finger, which we treat with extra-articular pinning.