Coronoid fractures account for 2 to 15% of the cases with elbow dislocations and usually occur as part of complex injuries. Comminuted fractures and non-unions necessitate coronoid fixation, reconstruction or replacement. The aim of this biomechanical study was to compare the axial stability achieved via an individualized 3D printed prosthesis with curved cemented intramedullary stem to both radial head grafted reconstruction and coronoid fixation with 2 screws. It was hypothesized that the prosthetic replacement will provide superior stability over the grafted reconstruction and screw fixation.

Following CT scanning, 18 human cadaveric proximal ulnas were osteotomized at 40% of the coronoid height and randomized to 3 groups (n = 6). The specimens in Group 1 were treated with an individually designed 3D printed stainless steel coronoid prosthesis with curved cemented intramedullary stem, individually designed based on the contralateral coronoid scan. The ulnas in Group 2 were reconstructed with an ipsilateral radial head autograft fixed with two anteroposterior screws, whereas the osteotomized coronoids in Group 3 were fixed in situ with two anteroposterior screws.

All specimens were biomechanically tested under ramped quasi-static axial loading to failure at a rate of 10 mm/min. Construct stiffness and failure load were calculated. Statistical analysis was performed at a level of significance set at 0.05.

Prosthetic treatment (Group 1) resulted in significantly higher stiffness and failure load compared to both radial head autograft reconstruction (Group 2) and coronoid screw fixation, p ≤ 0.002. Stiffness and failure load did not reveal any significant differences between Group 2 and Group 3, p ≥ 0.846.

In cases of coronoid deficiency, replacement of the coronoid process with an anatomically shaped individually designed 3D printed prosthesis with a curved cemented intramedullary stem seems to be an effective method to restore the buttress function of the coronoid under axial loading. This method provides superior stability over both radial head graft reconstruction and coronoid screw fixation, while achieving anatomical articular congruity. Therefore, better load distribution with less stress at the bone-implant interface can be anticipated. In the clinical practice, implementation of this prosthesis type could allow for early patient mobilization with better short- and long-term treatment outcomes and may be beneficial for patients with irreparable comminuted coronoid fractures, severe arthritic changes or non-unions.

Treatment of comminuted intraarticular calcaneal fractures remains controversial and challenging. Anatomic reduction with stable fixation has demonstrated better outcomes than nonoperative treatment of displaced intraarticular fractures involving the posterior facet and anterior calcaneocuboid joint (CCJ) articulating surface of the calcaneus. The aim of this study was to investigate the biomechanical performance of three different methods for fixation of comminuted intraarticular calcaneal fractures.

Comminuted calcaneal fractures, including Sanders III-AB fracture of the posterior facet and Kinner II-B fracture of the CCJ articulating calcaneal surface, were simulated in 18 fresh-frozen human cadaveric lower legs by means of osteotomies. The ankle joint, medial soft tissues and midtarsal bones along with the ligaments were preserved. The specimens were randomized according to their bone mineral density to 3 groups for fixation with either (1) 2.7 mm variable-angle locking anterolateral calcaneal plate in combination with one 4.5 mm and one 6.5 mm cannulated screw (Group 1), (2) 2.7 mm variable-angle locking lateral calcaneal plate (Group 2), or (3) interlocking calcaneal nail with 3.5 mm screws in combination with 3 separate 4.0 mm cannulated screws (Group 3). All specimens were biomechanically tested until failure under axial loading with the foot in simulated midstance position. Each test commenced with an initial quasi-static compression ramp from 50 N to 200 N, followed by progressively increasing cyclic loading at 2Hz. Starting from 200 N, the peak load of each cycle increased at a rate of 0.2 N/cycle. Interfragmentary movements were captured by means of optical motion tracking. In addition, mediolateral X-rays were taken every 250 cycles with a triggered C-arm. Varus deformation between the tuber calcanei and lateral calcaneal fragments, plantar gapping between the anterior process and tuber fragments, displacement at the plantar aspect of the CCJ articular calcaneal surface, and Böhler angle were evaluated.

Varus deformation of 10° was reached at significantly lower number of cycles in Group 2 compared to Group 1 and Group 3 (P ≤ 0.017). Both cycles to 10° plantar gapping and 2 mm displacement at the CCJ articular calcaneal surface revealed no significant differences between the groups (P ≥ 0.773). Böhler angle after 5000 cycles (1200 N peak load) had significantly bigger decrease in Group 2 compared to both other groups (P ≤ 0.020).

From biomechanical perspective, treatment of comminuted intraarticular calcaneal fractures using variable-angle locked plate with additional longitudinal screws or interlocked nail in combination with separate transversal screws seems to provide superior stability as opposed to variable-angle locked plating only.

Distal radius fractures have an incidence rate of 17.5% among all fractures. Their treatment in case of comminution, commonly managed by volar locking plates, is still challenging. Variable-angle screw technology could counteract these challenges. Additionally, combined volar and dorsal plate fixation is valuable for treatment of complex fractures at the distal radius. Currently, biomechanical investigation of the competency of supplemental dorsal plating is scant. The aim of this study was to investigate the biomechanical competency of double-plated distal radius fractures in comparison to volar locking plate fixation.

Complex intra-articular distal radius fractures AO/OTA 23-C 2.1 and C 3.1 were created by means of osteotomies, simulating dorsal defect with comminution of the lunate facet in 30 artificial radii, assigned to 3 study groups with 10 specimens in each. The styloid process of each radius was separated from the shaft and the other articular fragments. In group 1, the lunate facet was divided to 3 equally-sized fragments. In contrast, the lunate in group 2 was split in a smaller dorsal and a larger volar fragment, whereas in group 3 was divided in 2 equal fragments. Following fracture reduction, each specimen was first instrumented with a volar locking plate and non-destructive quasi-static biomechanical testing under axial loading was performed in specimen's inclination of 40° flexion, 40° extension and 0° neutral position. Mediolateral radiographs were taken under 100 N loads in flexion and extension, as well as under 150 N loads in neutral position. Subsequently, all biomechanical tests were repeated after supplemental dorsal locking plate fixation of all specimens. Based on machine and radiographic data, stiffness and angular displacement between the shaft and lunate facet were determined.

Stiffness in neutral position (N/mm) without/with dorsal plating was on average 164.3/166, 158.5/222.5 and 181.5/207.6 in groups 1–3. It increased significantly after supplementary dorsal plating in groups 2 and 3.

Predominantly, from biomechanical perspective supplemental dorsal locked plating increases fixation stability of unstable distal radius fractures after volar locked plating. However, its effect depends on the fracture pattern at the distal radius.

Introduction

The incidence of distal femoral fractures in the geriatric population is growing and represents the second most common insufficiency fracture of the femur following fractures around the hip joint. Fixation of fractures in patients with poor bone stock and early mobilisation in feeble and polymorbide patients is challenging. Development of a fixation approach for augmentation of conventional LISS (less invasive stabilization system) plating may result in superior long-term clinical outcomes and enhance safe weight bearing.

INTRODUCTION

Management of neglected residually displaced acetabular fractures is a big challenge. ORIF is often doomed to failure so a primary total hip replacement is usually kept in mind as a method of choice. However THR is a technically difficult and results are quiet unpredictable. OBJECTIVE. To present our experience with THR in maltreated grossly displaced acetabular fractures and to discuss operative technique and prognostic factors in that complicated surgery.

Objective: To compare anatomical and functional results after treatment of unstable C-type pelvic fractures with percutaneous iliosacral screws (PISS) and anterior sac-roiliac plating (ASIP) in order to verify the proper indications for both techniques.

Material And Methods: The series consists of 37 patients sustained C-type pelvic lesions with dislocation or fracture-dislocation of SI joint of witch 23 were treated by PISS and 14 by APIS. There were 24 males and 12 females of an average age 33 years (16–64 years). The average ISS in both groups was 26.5 and 23 respectively. The surgery was performed 1 – 18 days after trauma (mean 7 days). Screw fixation was carried out with 2 cannulated screws in the S1 body after close reduction in prone or supine position. ASIP was realised with 2 recon plates or DSP through iliac approach. Simultaneous anterior internal fixation was done in 16 PISS patients and 9 ASIP patients.

RESULTS: Average operative duration was 42 min (25–85) in PISS group and 105 min (70–130) in ASIP group (p< 0.001). The average perioperative blood loss was 50 ml (0–150 ml) and 560 ml (400–950) respectively (p< 0.01). The quality of reduction was evaluated according to Leung criteria. The excellent and good results were 17/23 after PISS (74%) and 13/14 after ASIP (93%): p< 0.005. One patient of each group died due to reasons unrelated to pelvic surgery and the remains were followed up for an average 28 months (10–64). Functional results were rated according Pohlemann et al. In PISS group excellent and good results were 17/22 (74%) and in ASIP group 12/13 (82%): p> 0.005. Except one case of fixation failure and nonunion after PISS without anterior stabilisation there was no major complication in every group.

Discussion: The both methods provide effective dorsal fixation and may be used succesfully in C-type injuries. PISS is much faster and bloodless procedure, but is in lower in respect of acceptable anatomical results. ASIP better reduction and is more suitable for fracture-dislocations. Fair functional results and complications in our series were slightly more common after PISS than after ASIP, but the differences were statistically insignificant. The single major comlication occured when anterior fixation was ignored.

Conclusions: Early after trauma when adequate reduction may be done by close manner PISS is prefferable as less traumatic intervention. When acceptable closed reduction can not be obtained, especially in delayed surgery, we consider ASIP as a method of choice for C-type pelvic fractures.

Objectives: To evaluate and compare the results of interlocking nailing (ILN) and plating (PL) in fresh humeral shaft fractures (HSF)

Material and Methods: During 7 years period 145 patients with HSF (84 males and 61 females) were operated and followed up for 8 – 60 months (mean 18 months). According to AO there were 64 Type A, 53 Type B and 28 Type C fractures. Of 18 open injuries there were 10 grades I, 5 grades II and 3 grades IIIA. There were 33 patients with polytrauma, 11 cases with associated limb injuries, 9 cases with floating elbow and 22 patients with primary neurological deficit. In 75 fractures ILN was performed and PL in rest 70.

Results: The mean operative time was 85 min for ILN vs./117 min for PL and the mean blood loss 100ml vs./250 ml. Healing occurred in 139(95.6%) fractures with mean healing time 75 days vs./85 days. Functional results according to Rommens score were as follows. Shoulder: excellent 62(82.6%) vs./55(78.5%), good 11(14.6%) vs./11(15.7%), poor 2(2.8%) vs./4(5.8%).

Elbow: excellent 69(92%) vs./52(74.3%), good 6(8%) vs./16(22.8%), poor 0 vs./2(2.9%). Complications noted were iatrogenic nerve palsy 1(1.3%) vs./12(17%), delayed union 5(7%) vs./2(3%), non union 1(1.3%) vs./5(7%), infection 0 vs./1(1.4%), fixation failure 1(1.3%) vs./5(7%) and reosteosynthesis 1(1.3%) vs./1(1.4%), shoulder impingement 8(11%) vs./2(3%).

Conclusions: Interlockimg nailing reduces risk of nerve injury and infection, provides more stability in segmental, complex and osteoporotic HSF. No significant differences in the term of healing in the both methods. Plating should be preferred in open Fx with incidental nerve palsy or vascular injury and juxtaarticular Fx, especially distally located. The method provides anatomical reduction, but requires extended approach and increases risk of iatrogenic nerve palsy.

Introduction: For a period of 7 years were treated in Emergency Hospital Pirogov 205 patients with humeral shaft fracture (HSF)–125 with interlocking nailing (ILN), 80 with AO plates, these include 55 delayed unions (DU) and nonunions (NU).

Material and methods: We treated 15 DU (2–4 months), 19 NU after conservative treatment (4–12 months), 15 NU after operative treatment and 6 recalcitrant NU. 23 of the cases were men at the average age of 43.9 (18–74) and 32–women, at the average age of 64.7 (43–88). NU according to Weber-Cech were–2 hypertrophic, 18 olygotrophic and 20 atrophic, as 7 of them were infected. The initial trauma in 14 cases was high energy. The most common predisposing factors at DU are: poor bone contact–distraction 11 cases, soft tissue interposition 8 cases. At NU after conservative treatment: soft tissue interposition 13 cases and inadequate vascularity–severe injury 6 cases, and at NU after operative treatment: mechanical instability–inadequate fixation 18 cases and excessive soft tissue striping 11 cases. The usual contributing factors are: metabolic bone disease 23 cases; obesity 18 cases; poor functional level 14 cases; smoking 14 cases; advanced age 11 cases. Osteosynthesis with AO plate were 23 cases and the remaining 32–interlocking nails. Bone grafting was done in 23 cases, decortications in 12 cases, and channel reaming–in 20 cases.

Results: All the cases that were treated with AO plates consolidated for the average period of 103 days (70–150) and the cases with interlocking nails (with the exception of 3–9%) for the average period of 108 days (160–240). As post-operative complications we had 6 (26%) cases of iatrogenic neurological injury with plate ostheosynthesis, 3 (10%) cases of shoulder impingements with ILN, one case of shaft fracture and infection in both methods. The patients were followed for minimum 12 months after bone union–clinical and X-ray examinations (12–60) months. We rated the final functional result according to Rommens score: excellent–29, very good–13, good–8, satisfactory–2, bad–3.

Conclusion: We think that DU are more appropriate for interlocking nailing. The cases that NU are a result of unsuccessful conservative treatment, because intramedullary channel was obstructed, is better to be treated by ostheosynthesis with plate. And the contrary–it is suitable to replace ostheosynthesis with AO plate with interlocking nails after extraction of the implants in addition to bone grafting.

Objective: A floating hip, e.i. combination of pelvic or acetabulat fracture with ipsilateral femoral fracture is uncommon condition, but posing considerable problems such as how to manage each component of the injury and what are the treatment priorities. The aim of the syudy is to report our experience with surgical treatment of traumatic floating hip.

Material and methods: For the 4-year period in our institution 15 patients with floating hips (10 mails, 5 females, average age 38 years) were treated operatively. There were 10 unstable pelvic ring disruptions B and C types and 5 displaced acetabular fractures, combined with 2 neck, 11 shaft and 2 supracondylar femoral fractures. Six patients were operated simultaneously for both components and in the rest definitive pelvic surgery were done at a second stage. pelvic girdle was stabilized by a variety of methods: anterior sacro-iliac plates, iliosacral lag screws, transsacral posterior plaates. Acetabular fractures were all treated by ORIF. For femoral fractures nailing was done in 8 cases, plating in 5 and cervical screw fixation in 2.

Results: All fractures healed in time. Two superficial femoral infections resolved after local care. Results for pelvic injuries were estimated according to Pholemann score and for acetabular fractures – to Matta scale. In respect to pelvic fractures 5 ecxellent, 3 good and 2 poor results were noted, and regarding acetabular fractures 3 exccelent, 1 satisfactory and 1 poore results. All femoral fractures united in good position. Overall final outcome was excellent in 8, good in 3, fair in 1 and poor in 3 patients.

Conclusions: Surgical treatment is a method of choice for a floating hip. ORIF of pelvic ring and locking nailing of the femur result in best outcome. Simultaneous procedure provides more rapid recovery, but should be carried out only in stable patients. If staged surgery is planned, stabilisation of the femur should be done prior to definitive pelvic fixation in order to facilitate later pelvic surgery.