Locking plates in distal humerus fractures： study of 43 patients

Objective:The treatment of multifragmentary,intraarticular fractures of the distal humerus is difficult,even in young patients with bone of good quality.Small distal fragment,diminished bone mineral qu...     

Locking versus standard screw fixation for acetabular cups: is there a difference?

Introduction

Total hip replacement has been established as a valid treatment option for displaced subcapital fractures. However, insufficient primary fixation may be the reason for early loosening in these osteoporotic patients. Primary fixation of the cup is usually achieved by press-fit fixation that can be enhanced using screws. Locking the screws into their respective cups may seem to improve the primary fixation of the construct, as locked plates proved superior fixation for osteoporotic fractures.

Methods

The study consisted of three groups: in each group, three cups were fixed into blocks of foam bone using press-fit technique. In the first group, no additional screws were used, in the second group two standard screws were inserted, while in the third group two acetabular screws were cemented into the cup to simulate locked screw fixation. Load was applied onto the rim of the acetabular component to cause shearing between the cup and the block. Cup fixation was examined by a loading machine that acquired load versus displacement. The stiffness (load vs. displacement) was calculated.

Results

Screws, either locked or non-locked, enhanced cup fixation by 26 % (p value <0.01). No significant changes were found between the locking and non-locking screws groups.

Discussion

These experimental results indicate that acetabular screws enhance primary cup fixation. This may become significant in conditions where the acetabular bone stock is suboptimal, such as when performing total hip arthroplasty after displaced subcapital fractures. However, there is no superiority for locked screws over standard screw fixation.     

The Locking Compression Paediatric Hip Plate?: technical guide and critical analysis

Purpose

Osteotomies of the proximal femur and stable fixation of displaced femoral neck fractures are demanding operations. An LCP Paediatric Hip Plate™ was developed to make these operations safer and less demanding. The article focuses on the surgical technique and critically analyses the device.

Methods

Between 2006 and 2008, 30 hips in 22 patients underwent surgery. Patients’ demographics, perioperative details, postoperative outcome and complications were retrospectively collected and analysed.

Results

Patients’ diagnoses included persistent congenital hip dysplasia (n = 4), neuropathic hip dysplasia (n = 9), idiopathic ante/retroversion (n = 8), femoral neck fracture (n = 3), Perthes’ disease (n = 2), deformity after slipped capital femoral epiphysis (SCFE), congenital femoral neck pseudarthrosis, deformity after pelvic tumour resection and malunion following proximal femoral fracture (one each). In 21 of 22 patients, the postoperative radiographs showed corrections as planned. Two cases had to be revised for screw loosening. Intraoperative handling using the plate was excellent in all cases.

Conclusions

In our case series of 30 hip operations, the LCP Paediatric Hip Plate™ was shown to be safe and applicable in the clinical setting with excellent results and a low complication rate. We consider that the LCP Paediatric Hip Plate™ is a valuable device for correction of pathological conditions of the proximal femur and for fixation of displaced femoral neck fractures in children. Larger studies should be carried out to better quantify the risk of clinically relevant complications.     

The Peroneus Quartus Muscle in a Locking Phenomenon of the Ankle: A Case Report

We present the case of a 64-year-old female who was referred to us with an unexplained clicking and locking phenomenon of the right ankle. The magnetic resonance imaging findings suggested a longitudinal tear of the peroneus brevis tendon. During tendoscopy, not only was a Raikin type B intrasheath tendon subluxation visible, but also a peroneus quartus muscle. The peroneus brevis tear was tubularized and the peroneus quartus muscle resected, which resolved the patient's complaints.     

Are Volar Locking Plates Superior to Percutaneous K-wires for Distal Radius Fractures? A Meta-analysis

Background

Distal radius fractures are common, costly, and increasing in incidence. Percutaneous K-wire fixation and volar locking plates are two of the most commonly used surgical treatments for unstable dorsally displaced distal radius fractures. However, there is uncertainty regarding which of these treatments is superior.

Questions/purposes

We performed a meta-analysis of randomized controlled trials to determine whether patients treated with volar locking plates (1) achieved better function (2) attained better wrist motion, (3) had better radiographic outcomes, and (4) had fewer complications develop than did patients treated with K-wires for dorsally displaced distal radius fractures.

Methods

We performed a comprehensive search of MEDLINE (inception to 2014, October Week 2), EMBASE (inception to 2014, Week 42), and the Cochrane Central Register of Controlled Trials to identify relevant randomized controlled trials; we supplemented these searches with manual searches. We included studies of extraarticular and intraarticular distal radius fractures. Adjunctive external fixation was acceptable as long as the intent was to use only K-wires where possible and external fixation was used in less than 25% of the procedures. We considered a difference in the DASH scores of 10 as the minimal clinically important difference. We performed quality assessment with the Cochrane Risk of Bias tool and evaluated the strength of recommendations using the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach. Seven randomized trials with a total of 875 participants were included in the meta-analysis.

Results

Patients treated with volar locking plates had slightly better function than did patients treated with K-wires as measured by their DASH scores at 3 months (mean difference [MD], 7.5; 95% CI, 4.4–10.6; p < 0.001) and 12 months (MD, 3.8; 95% CI, 1.2–6.3; p = 0.004). Neither of these differences exceeded the a priori-determined threshold for clinical importance (10 points). There was a small early advantage in flexion and supination in the volar locking plate group (3.7° [95% CI, 0.3°–7.1°; p = 0.04] and 4.1° [95% CI, 0.6°–7.6°; p = 0.02] greater, respectively) at 3 months, but not at later followups (6 or 12 months). There were no differences in radiographic outcomes (volar tilt, radial inclination, and radial height) between the two interventions. Superficial wound infection was more common in patients treated with K-wires (8.2% versus 3.2%; RR = 2.6; p = 0.001), but otherwise no difference in complication rates was found.

Conclusions

Despite the small number of studies and the limitations inherent in a meta-analysis, we found that volar locking plates show better DASH scores at 3- and 12-month followups compared with K-wires for displaced distal radius fractures in adults; however, these differences were small and unlikely to be clinically important. Further research is required to better delineate if there are specific radiographic, injury, or patient characteristics that may benefit from volar locking plates in the short term and whether there are any differences in long-term outcomes and complications.

Level of Evidence

Level I, therapeutic study.

Electronic supplementary material

The online version of this article (doi:10.1007/s11999-015-4347-1) contains supplementary material, which is available to authorized users.     

Current Total Knee Designs: Does Baseplate Roughness or Locking Mechanism Design Affect Polyethylene Backside Wear?

Clinical Orthopaedics and Related Research® - Tibial baseplate roughness and polyethylene-insert micromotion resulting from locking-mechanism loosening can lead to polyethylene backside wear...     

Winkelstabile Verriegelung von Markn?geln mit dem Angular Stable Locking System? (ASLS)

Objective

Greater stability in intramedullary osteosynthesis using angle-stable fixation with intramedullary nails and proximal locking screws. A novel screw-and-sleeve system (ASLS?, Synthes GmbH, Oberdorf, Switzerland) is applied using normal cannulated nails. Decisions can be made intraoperatively.

Indications

This technology widens the range of indications for intramedullary nailing: The smaller and less stable the fragment requiring fixation, the greater the indication for angular stable fixation of the proximal and/or distal fragment. Femoral, tibial and humeral fractures, intramedullary osteosynthesis in osteoporotic bone and ante- and retrograde nailing. Particularly in the case of retrograde nailing, sustained prevention of nail toggling is achieved.

Contraindications

None.

Surgical technique

Drill with the first drill bit, which has the same core diameter as the screw shaft. Drill the cortex to the external diameter of the sleeve. Place the sleeve on the tip of the screw. The screw?Csleeve combination is then advanced through the larger near hole until the sleeve-covered screw tip sits in the locking hole of the intramedullary fixation nail. Advance the screw. As the screw diameter becomes larger, the sleeve expands resulting in an angular stable locking effect. The screw is then advanced until the head of the screw sits on the exposed surface of the cortex. The hole is filled with the expanded part of the screw shaft beneath the screw head. The necessary 1?C3 turns are cut by the self-tapping flute on the screw.

Postoperative management

According to experience to date, this form of angle-stable fixation enables earlier and/or greater partial mobilization or earlier full mobilization. In all other respects, the guidelines for aftercare in intramedullary nailing apply.

Results

A multi-center pilot study has shown the technique to be reproducible and simple. There have been no complications using this technique to date. Biomechanical laboratory studies have demonstrated that stability with respect to axial and torsional loading is statically and dynamically higher than with conventional nailing. Device failure occurs later. Further applications as well as results of a prospective randomised study currently under way will show how great the clinical advantages ultimately prove to be.     

Ulnar Styloid Fracture in Distal Radius Fractures Managed with Volar Locking Plates: To Fix or Not?

Distal radius fracture is usually associated with ulnar styloid fracture. Whether to fix the ulnar styloid or not remains a surgical dilemma as some surgeons believe that their repair is imperative while others feel that they should be managed conservatively. This prospective study involved 47 patients with unilateral fracture of the distal radius who met the inclusion criterion and underwent open reduction and internal fixation with volar locking plates; 28 patients (12 males and females = 16) had an associated ulnar styloid fracture (Group A) while 19 (7 males; 12 females) did not have any ulnar styloid fracture (Group B). At the time of final evaluation both the groups were compared clinically by measuring the grip strength and range of motion around the wrist and the radiologically by measuring radial angle, radial length, volar angle and ulnar variance. Subjective assessment was done using DASH score and final assessment using Demerit point system of Saito. In Group A, average time for consolidation was 9.4 weeks, 17 patients developed non-union of the ulnar styloid, average DASH scores was 4.4 and according to Demerit point system of Saito, there were 78.5 % excellent, 17.9 % good and 3.6 % fair results; there were 2 cases of loss of reduction out of which one had persistent ulnar sided wrist pain. In Group B the average time for consolidation was 10.2 weeks, average DASH score was 3.8.and Demerit point system of Saito yielded 78.9 % excellent, 15.8 % good and 5.3 % fair results. There was one case of loss of reduction and one case of carpal tunnel syndrome which was managed conservatively. Both groups attained excellent range of motion, grip strength and well maintained the post operative radiological parameters. The comparison of clinico-radiological parameters in both groups was found to be statistically insignificant. To conclude, ulnar styloid fracture or its non union does not affect the outcome of an adequately fixed distal end radius fracture. We urge caution in electing operative treatment of non-united fracture of the ulnar styloid until better scientific report for treatment of pain associated with these fracture is available.     

Posterior Locking Plate Fixation of Bartoníček Type IV Posterior Malleolar Fracture: A Focus on Die-Punch Fragment Size

Die-punch fragments refer to articular cartilage and subchondral bone embedded in cancellous bone as part of an intra-articular fracture. Bartoní?ek type IV posterior malleolar fractures with associated die-punch fragments are rare, and the appropriate surgical approach remains unclear. We determined outcomes, and the effect of die-punch fragment size on outcomes, for 32 patients with Bartoní?ek type IV posterior malleolar fractures with die-punch fragments between January 2015 and December 2017. Mean follow-up for all patients was 23.8 (range 20.0-30.0) months. At the final follow-up visit, mean ankle dorsal extension was 24.6° and plantar flexion was 40.0°; American Orthopaedic Foot and Ankle Society ankle-hindfoot score was 88.6 ± 4.3; visual analog scale weightbearing pain score was 1.5 ± 0.6; and Bargon traumatic arthritis score was 0.8 ± 0.4. There were no severe complications. We divided patients into a small-fragment (≤3 mm) group (n = 12) and large-fragment (>3 mm) group (n = 20). The Bargon scores at final follow-up were 0.5 and 1, respectively (P=.02). There were no statistically significant differences between the 2 groups for the other outcome scores at various time intervals. The posterolateral approach with distal locking plate internal fixation for Bartoní?ek type IV posterior malleolar fractures with die-punch fragments can result in excellent anatomical reduction of the collapsed articular surface and the displaced fragment from the tibial plafond, recovery of articular surface congruity, and maintenance of joint stability. Die-punch fragment size may not impact clinical and functional outcomes but may contribute to post-traumatic arthritis.