Functional results and unfavorable events after treatment of proximal humerus fractures using a new locking plate system.

BACKGROUND: Proximal humerus fractures are often treated with a fixed-angle titanium plate osteosynthesis. Recently, plates made of alternative materials such as carbon fibre-reinforced polyetheretherketone (CFR-PEEK) have been introduced. This study presents the postoperative results of patients treated with a CFR-PEEK plate. METHODS: Patients with proximal humerus fractures treated with a CFR-PEEK plate (PEEKPower™ Humeral Fracture Plate (HFP)) were included. In follow-up examination, age and gender adjusted Constant-Murley Score (ACS), Subjective Shoulder Value (SSV), Quick Disabilities of the Arm, Shoulder and Hand Score (QDASH) and pain score (Visual Analog Scale (VAS)) were analyzed. General condition at follow-up was measured by European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L). Range of motion was recorded. In addition, radiographs at follow-up, unfavorable events and revision rate were analyzed. RESULTS: In total, 98 patients (66.0 ± 13.2 years, 74 females, 24 males) were reexamined. Mean follow-up was 27.6 ± 13.2 months. There were 15 2-part, 28 3-part and 55 4-part fractures. The functional scores showed good results: SSV 83.3 ± 15.6%, QDASH 13.1 ± 17.0 and ACS 80.4 ± 16.0. A 4-part-fracture, head split component, nonanatomic head shaft reposition and preoperative radiological signs of osteoarthritis were significant negative predictors for poorer clinical scores. Unfavourable events were observed in 27 patients (27.6%). Revision surgery was performed in 8 (8.2%) patients. Risk factors for an unfavourable event were female gender, age of 50 years and older, diabetes, affected dominant hand, 4-part fracture, head split and preoperative radiological signs of osteoarthritis. CONCLUSION: There are several advantages of the CFR-PEEK plate (PEEKPower™ Humeral Fracture Plate (HFP)) such as the polyaxial screw placement and higher stability of locking screws. In summary, the CFR-PEEK plate osteosynthesis is a good alternative with comparable clinical results and some biomechanical advantages. Proximal humerus fractures show good clinical results after treatment with a CFR-PEEK plate. The revision rate and the risk of unfavorable events are not increased compared to conventional titanium plate osteosynthesis. LEVEL OF EVIDENCE: IV.

Clinical analysis of the acromial height-measuring device combined with new-type clavicular hook plate and standard clavicular hook plate in the treatment of Neer type II distal clavicle fractures.

BACKGROUND: Distal clavicular fracture is a shoulder joint injury that is common in clinical settings and is generally surgically treated using the clavicular hook plate technique with a confirmed curative effect. However, symptoms, such as shoulder abduction limitation, shoulder discomfort, and postoperative joint pain, may occur in some patients. To overcome these problems, after a previous study we developed an acromial height-measuring device and a new type of clavicular hook plate. This study aimed to investigate whether an acromial height-measuring device combined with an improved new-type clavicular hook plate can better reduce the incidence of complications and improve postoperative function. To provide patients with better treatment effects, an acromion gauge and clavicular hook plate are used. METHODS: A retrospective analysis was performed on 81 patients with distal clavicular fractures admitted to our hospital. They were divided into experimental and control groups according to different plates, and the Constant-Murley score, visual analogue scale score, incidence of acromion osteolysis, and incidence of subacromial impingement syndrome were compared. RESULTS: Compared with the standard clavicular hook plate, the acromial height-measuring device combined with the new-type clavicular hook plate in the treatment of distal clavicle fractures has a lower incidence of subacromial impingement syndrome with better postoperative functional recovery and quality of life. CONCLUSIONS: We considered the acromial height-measuring device combined with the new clavicular hook plate to be a safe and promising alternative to distal clavicular fractures.

Application of Vacuum-Assisted Closure Therapy and Hyperbaric Oxygen Therapy for an Exposed Titanium Plate After Mandible Reconstruction.

The authors report a case of an 84-year-old woman with an exposed mandibular plate after reconstruction, which finally healed with combination therapy using vacuum-assisted closure therapy and hyperbaric oxygen therapy. The woman was diagnosed with mucosal carcinoma of the right oral cavity. During reconstruction after segmental excision of the mandible, a titanium plate was selected based on several risk factors. After the operation, the plate became exposed at the center of the chin. A second surgery was deemed inappropriate because of her age, malnutrition, and recurrent aspiration pneumonia. Instead, combination therapy consisting of vacuum-assisted closure therapy and hyperbaric oxygen therapy was initiated, leading to epithelizaion of the wound. Adapt Barrier Rings was effectively used to generate a stable negative pressure at the complicated craniofacial wound. A surgical or conservative approach is chosen as salvage treatment of an exposed plate. In this patient, only conservative treatment involving combination therapy resulted in complete healing of the wound with plate exposure. This patient highlights 2 important clinical issues: combination therapy was effective for an exposed mandibular plate, and a dressing technique using Adapt Barrier Rings enabled stable negative pressure in the craniofacial wound.

Heating produced by therapeutic ultrasound in the presence of a metal plate in the femur of canine cadavers / Aquecimento gerado pelo ultrassom terapêutico em presença de placa óssea metálica no fêmur de cadáveres caninos

The present study aimed to assess the heat generated by a therapeutic ultrasound (TUS) in a metal bone plate and adjacent structures after fixation to the femur of canine cadavers. Ten pairs of hind limbs were used, and they were equally distributed between groups that were subjected to 1- and 3-MHz frequencies, with each frequency testing 1- and 2-W/cm² intensities. The right hind limb was defined as the control group (absence of the metal plate), and the left hind limb was the test group (presence of the metal plate). Therefore, the control groups (CG) were denominated CGI, using TUS with 1-MHz frequency and 1-W/cm² intensity; CGII, using 1-MHz frequency and 2-W/cm² intensity; CGIII, using 3-MHz frequency and 1-W/cm² intensity; and CGIV, using 3-MHz frequency and 2-W/cm² intensity. For each control group, its respective test group (TG) was denominated TGI, TGII, TGIII and TGIV. The TUS was applied to the lateral aspect of the thigh using the continuous mode and a 3.5-cm² transducer in a 6.25-cm² area for 2 minutes. Sensors were coupled to digital thermometers that measured the temperature in different sites before (t0) and after (t1) of the TUS application. The temperatures in t1 were higher in all tested groups. The intramuscular temperature was significantly higher (P<0.05) in the groups used to test the 3-MHz frequency in the presence of the metal plate. The therapeutic ultrasound in the continuous mode using frequencies of 1 and 3 MHz and intensities of 1 and 2 W/cm2 for 2 minutes caused heating of the metal plate and adjacent structures after fixation to the femur of canine cadavers...

O objetivo deste estudo foi avaliar o aquecimento gerado pelo ultrassom terapêutico (UST) na placa óssea metálica e estruturas adjacentes após a fixação no fêmur de cadáveres caninos. Foram utilizados dez pares de membros pélvicos, distribuídos igualmente entre os grupos que utilizaram as frequências de 1 e 3 MHz. Cada frequência testou as intensidades de 1 e 2 W/cm², sendo que o membro pélvico direito foi definido grupo controle (ausência da placa óssea metálica) e o membro pélvico esquerdo o grupo teste (presença da placa óssea metálica). Portanto, os grupos controles foram denominados GCI, com UST na frequência de 1 MHz e intensidade de 1 W/cm²; GCII, com 1 MHz e 2 W/cm²; GCIII, com frequência de 3 MHz e intensidade de 1 W/cm²; e GCIV, com 3 MHz e 2 W/cm². Para cada grupo controle, seu respectivo grupo teste foi denominado GTI, GTII, GTIII e GTIV. O UST foi aplicado na face lateral da coxa, utilizando o modo contínuo, transdutor de 3,5cm², em uma área de 6,25cm², durante dois minutos. Foram utilizados sensores acoplados a termômetros digitais que mediram a temperatura em diferentes locais antes (t0) e após (t1) a aplicação do UST. Pode-se verificar que as temperaturas em t1 foram maiores em todos os grupos testados. Os grupos que testaram a frequência de 3 MHz demonstraram que a temperatura intramuscular foi significativamente maior (P<0,05) na presença da placa óssea metálica. O ultrassom terapêutico no modo contínuo de 1 e 3 MHz e intensidades de 1 e 2 W/cm2 durante dois minutos promove o aquecimento da placa óssea metálica e estruturas adjacentes após a fixação no fêmur de cadáveres caninos...

[Utilization of a porous alumina ceramic spacer in tibial valgus open-wedge osteotomy: fifty cases at 16 months mean follow-up]. / Utilisation d'une cale en céramique d'alumine poreuse dans l'ostéotomie tibiale de valgisation par ouverture interne: cinquante cas avec un recul moyen de 16 mois.

PURPOSE OF THE STUDY: The aim of this work was to study the behavior of an inert porous alumina ceramic spacer used with a plate fixation for open-wedge tibial valgus osteotomy in patients with osteoarthritis of the knee and genu varum. MATERIAL AND METHODS: The population included 50 patients who underwent surgery between October 1994 and December 2000. There were 31 women and 19 men, mean age 55 years at surgery (26 right knees and 24 left knees). Patients were reviewed at 3 weeks, 6 weeks, 3 months, 6 months, and one year, then every 2 years. Clinical and radiological data were available for all patients. RESULTS: Mean follow-up was 16 months. Two patients were lost to follow-up at 5 and 6 months. The results of the open-wedge tibial osteotomy were in agreement with the usual outcome reported in the literature concerning pain relief, functional recovery, joint motion, angle correction, and good preservation of the clinical and radiological result. Three fracture lines were observed on the lateral tibial plateau but did not affect final outcome or angle correction. There was however one case with loss of correction due to fracture of the screws. Radiographically, at 6 months, there were 9 thin lucent lines around the spacer (24%) which did not affect final outcome. Bone healing was achieved at 3 months on the average in all cases except 2 (4%) where healing was achieved at 8 and 13 months. DISCUSSION: The porous alumine spacer is a reliable biocompatible and mechanically stable element helpful for achieving bone healing. Integration into bone tissue was radiographically satisfactory. There were no specific complications related to use of the spacer.

Alendronate did not inhibit instability-induced bone resorption. A study in rats.

Alendronate is a bisphosphonate that can decrease osteoclastic activity. It has been suggested as treatment for periprosthetic osteolysis. We used 48 rats, of which 32 had a plate implant on one tibia, to study the effect of alendronate on bone resorption at an unstable implant-bone interface. The plate has a handle on top, which can be grasped through the skin and turned, to create a sliding motion of a titanium surface against the underlying bone. This is known to result in bone resorption, which was studied by histomorphometry. Osmotic minipumps were used to administer alendronate at 0.063 mg/kg/day or saline. The systemic effect of the treatment was assessed by ashing the proximal metaphyses of the tibia of the contralateral unoperated leg. The ash-weight was increased in the alendronate-treated group by 43% (p = 0.0001), corresponding to histological changes in the metaphyseal bone. There was no inhibition of the instability-induced bone resorption at the test surface by alendronate: bone was being resorbed and replaced by a tissue similar to a loosening membrane.

Factors involved in long- and short-term mandibular plate exposure.

OBJECTIVES: To evaluate and to compare rates and timing of exposure of alloplastic mandibular plates by plate type and tissue reconstruction technique. DESIGN: A retrospective review series of 92 consecutive patients for 4 years (mean follow-up, 30 months). SETTING: National Cancer Institute-designated comprehensive cancer center in a freestanding cancer hospital. PATIENTS: Seventy-nine patients received alloplastic mandibular plates for segmental defects, and 13 patients received compression plates for mandibular osteotomies following ablative cancer surgery, including 21 titanium hollow osseointegrating reconstruction, 41 Storz, 16 Synthes, and 5 AO/ASIF (Arbeitsgemein schott fur Ostcosynthese fragen/Association for the Study of Internal Fixation) plates. Primary flap repair was provided by 71 pedicled soft tissue and 19 osseocutaneous free flaps, with primary closure in the remaining 2. INTERVENTION: Most of the reconstructions of the mandibular defect was with an alloplastic plate with musculocutaneous flap or revascularized bone graft. OUTCOME MEASURES: Clinically apparent intraoral or extraoral plate exposure. RESULTS: Plate exposure occurred in 25 cases. Nine plates were exposed extraorally, at a mean postoperative interval of 40 weeks. The remaining 16 plates were exposed intraorally at a mean postoperative interval of 16 weeks. There was no significant difference in the exposure rates of different plate types or methods of reconstruction. The titanium hollow osseointegrating reconstruction plate had a similar exposure rate compared with the other plates. Size and site of the defect were the only significant predictors of plate exposure Radiotherapy and postoperative complications did not affect the rate of exposure. CONCLUSIONS: Extraoral plate exposure occurs less commonly and later in the postoperative period than intraoral exposure, suggesting different causes. Plate type and type of flap reconstruction do not affect the rate of exposure. This may reflect long follow-up.

Biochemical changes in bone grafts stabilized with rigid plates. I. Cancellous grafts.

The effect of rigid plate fixation on the chemical composition of cancellous interposition grafts was studied in rabbit-fibular bones. The concentrations of hexosamines and, to a lesser degree, of hydroxyproline and nitrogen, were high in the graft for the first 6 weeks, decreased from weeks 6 to 12, but remained higher than the corresponding values for the controls throughout the experiment (52 weeks). The ratio of hexosamines to hydroxyproline was highest for the graft at 3 weeks, indicating formation of cartilage and osteoid. The initially low calcium concentration of the graft increased by 35 per cent from weeks 1 to 6, decreased from weeks 6 to 12, and remained below normal thereafter in comparison with corresponding values for the cortical host bone. The ratio of calcium to hydroxyproline increased throughout the experiment, reflecting maturation of the graft to lamellar bone. Thus, biochemically the early incorporation of rigidly fixed cancellous interposition grafts resembles the healing of unimmobilized fractures by callus formation.

Biochemical changes in bone grafts stabilized with rigid plates. II. Cortical grafts.

The effect of rigid plate fixation on the chemical composition of cortical interposition grafts were studied in rabbit tibio-fibular bones. The concentration of hexosamines increased both in the graft and in the host bone during the first 6 weeks, but thereafter decreased. The concentrations of hydroxyproline and nitrogen increased throughout the experiment. The ratio of hexosamines to hydroxyproline increased in the graft for the first 6 weeks, indicating formation of immature osteoid and bone during this period, but thereafter decreased. The calcium concentration of the graft decreased significantly during the first 12 weeks and remained below normal (-10 to -19 per cent). The mineralization of the graft, assessed by the ratio of calcium to hydroxyproline, decreased continually. The results suggest that cortical bone grafts stabilized with rigid plates heal with only slight chemical signs of callus formation. The demineralization of the graft reflects the porotic changes that take place under the plate.