We have designed a sort of multi-functional bone forceps for use as orthopedic surgical instruments to grip, bend and cut the spicula. It is labor-saving and easily installed. Its left and right clamp bodies are connected by a rivet to hold the spicula, and the pressure-regulating shank is connected with the clamp seat body at the right top of the clamp body by a rivet. It is used to curve the spicula. At an appropriate location on the pressure-regulating shank is a pin-cutting chip. On the right body rotating disc-clamp, there is a rectangular open cutting groove to be in use for cutting the specula with the role of pin-cutting chip. Being characterized by the use of mechanical leverage, the manipulations of holding and bending are less arduous. After achieving the 90-degree bend, the operator can cut off the specula successfully. The operation is easy to perform and labor-saving; the forceps can further meet the actual clinical demand.
Equipment Design ; Fracture Fixation, Internal ; instrumentation ; Humans ; Surgical Instruments

OBJECTIVETo investigate the influence on fracture stability by different pin construct during percutaneous pinning for the treatment of proximal humerus fractures.

METHODSEighteen pairs (36) adult fresh-frozen humeri were match-paired and divided into 4 groups. Dual-energy bone density scan had been used in order to rule out the influence by different degrees of osteoporosis of the cadaver. Two-part surgical neck fracture model was carried out unanimously in all 36 humeri. Four terminal threaded pins (2.5 mm in diameter) were used in fixation for all specimen. Parallel type pinning (box type) were carried out in 2 groups and convergent type pinning (fan shape) in the other 2 groups. Instron5566 biomechanical tester was applied in determining both anti-shear and anti-torsion ultimate load of each specimen.

RESULTSThere was no statistical difference between parallel pin construct and convergent construct in regard of anti-shear resistance (P = 0.73). But by mean of anti-torsion resistance, the parallel construct had significant advantage over the convergent construct (P = 0.04).

CONCLUSIONAccording to our biomechanical data, parallel pin construct seems to have better torsional stability. We suggest that parallel pin fixation should be applied whenever possible. Convergent pin construct should be considered when parallel construct is not possible or the distance between pins are too small (< 1 cm).

Biomechanical Phenomena ; Bone Nails ; Cadaver ; Fracture Fixation, Internal ; instrumentation ; methods ; Humans ; Shoulder Fractures ; physiopathology ; surgery

OBJECTIVETo evaluate the biomechanical properties of tibial plateau depressed fracture fixed with a net-fixation of Kirschner wires.

METHODSTwenty homemade fracture models were fixed with eight 1.5 mm Kirschner wires in a net-fixation; 20 homemade fracture models were fixed with two 3.5 mm cortical screws. Plane-compressed and dot-compressed test were made on each 10 models of the two groups. The maximal force of anti-ompress and stiffness were measured and evaluated.

RESULTSIn plane-compressed test,mean maximal force of anti-compress and stiffness for screw fixation was (1,925.31 +/- 444.26) N and (2.28 +/- 0.53) N/mm2, respectively, for net-fixation was (1,609.62 +/- 277.72) N and (1.90 +/- 0.33) N/mm2, respectively. There was no statistical difference between the two fixation methods (P > 0.05). In dot-compressed test,mean maximal force of anti-compress and stiffness for screw fixation was (411.13 +/- 233.88) N and (2.66 +/- 1.52) N/mm2,respectively,for net-fixation was (1,105.58 +/- 290.66) N and (7.18 +/- 1.89) N/mm2,respectively,the net-fixation was better than that of the screw fixation (P< 0.01).

CONCLUSIONTreatment of tibial plateau depressed fracture with a net-fixation of Kirschner wires is a biological fixation and is a reliably method.

Biomechanical Phenomena ; Bone Screws ; Fracture Fixation, Internal ; instrumentation ; Mechanical Phenomena ; Tibial Fractures ; surgery

OBJECTIVETo design a kind of internal fixation device to treat the syndesmosis injury.

METHODSThe elastic syndesmosis hook plate is made of medical stainless steel alloy, which is consisted of locking or common screw fixing hole of the tibial side for the head, tridentate fork like arc anatomical fibula side plate for the tail and serpentine elastic connecting body. By reduction of the joint of the lower tibia and fibula, the steel plate tail is fixed at the side of the fibula and the head is fixed at the side of the tibia for fixing the symphysis.

RESULTSThe design of elastic syndesmosis hook plate is reasonable, and the operation is convenient. There is no need to penetrate the substantia ossea and the plate has elastic micro-movement feature, the problem of internal fixation breakage and loosening is avoid in huge degree, so it is safe and reliable.

CONCLUSIONThe elastic syndesmosis hook plate is a new type medical apparatus of internal fixation of the symphysis, which is worthy of clinical popularization and application.

Ankle Injuries ; Bone Plates ; Bone Screws ; Fibula ; Fracture Fixation, Internal ; instrumentation ; Humans ; Stainless Steel ; Tibia

Arthroplasty, Replacement, Hip ; Fracture Fixation, Internal ; Hip Fractures ; surgery ; Humans ; Precision Medicine ; instrumentation ; methods ; Preoperative Period

OBJECTIVETo study the biodegradation process of the bioabsorbable mini-plate (LactoSorb) and its influence on bone healing.

METHODS15 mature New Zealand White Rabbits were selected as the experimental animals. The bilateral zygomatic arch were fractured using a fissure bur. One side was fixed with the bioabsorbable mini-plate and the other side was fixed with Titanium mini-plate as a control. 5 animals were killed after 4, 12, and 24 weeks post operation respectively for radiographic and histologic study.

RESULTSAt 4 weeks, the absorbable plate changed from transparent to opaque and its dimensions was enlarged. The bone gaps of both groups were filled with new bone. No inflammatory cells were found in both groups. At 12 weeks, the absorbable plate broke to small pieces or particles, its dimensions reduced greatly but the outline could still been recognized. The bone continuity had been reestablished in both groups. At 24 weeks, the absorbable plate was resorbed completely. Only the residual screw could be seen in the screw hole. Complete bone healing was seen in both groups. No histological differences of bone healing were found at this stage.

CONCLUSIONThe absorbable plate demonstrates excellent biocompatibility. No adverse local inflammatory reactions were found during the plate was absorbed gradually. In the non-weight baring area, the absorbable plate provides the same fixation stability as that of the metal plate.

Absorption ; Animals ; Bone Plates ; Female ; Fracture Fixation, Internal ; instrumentation ; Male ; Rabbits

Adolescent ; Bone Screws ; Child ; Female ; Femoral Neck Fractures ; surgery ; Fracture Fixation, Internal ; instrumentation ; Humans ; Male

OBJECTIVETo summarize application of rafting K-wires technique for tibial plateau fractures.

METHODSFrom January 2013 to January 2015,45 patients with tibial plateau fractures were treated by locking plate with rafting K-wires, including 33 males and 12 females with an average of 44.2 years old ranging from 22 to 56 years old. According to Schatzker classification, 6 cases were type II, 8 were type Ill, 4 were type IV, 4 were type V, and 5 were type VI. Allogeneic bone graft were performed for bone defects. All patients were fixed with two to five K-wires. Part of weight loading were encouraged at 3 months after operation,and full weight-loading were done at 5 months after operation. Postoperative complications were observed,and Rasmussen clinical and radiological assessment were used to evaluate clinical results.

RESULTSAll Patients were followed up from 10 to 23 months with average of 14 months. According to Rasmussen clinical and radiological assessment, clinical scores 23.58 ± 6.33, radiological scores were 14.00 ± 6.33; and excellent and good rates were 82.2% and 77.8% respectively. Four patients occurred severe osteoporosis and collapse of articular surface; 5 patients occurred traumatic arthritis.

CONCLUSIONRafting K-wires technique with anatomized armor plate could effective fix and support platform collapse and joint bone fragments, increase support surface area and reduce postoperative reduction loss rate.

Adult ; Bone Wires ; Female ; Fracture Fixation, Internal ; instrumentation ; methods ; Humans ; Male ; Middle Aged ; Tibial Fractures ; surgery

Acetabular is an important human joint for weight bearing. Quadrilateral plate is a crucial structure of medial acetabulum with special morphology and important function. Quadrilateral plate fractures are common fracture in acetabulum. Quadrilateral plate fracture is hard to expose and reduction because it is in the medial of acetabulum. At the same time,the bone in the quadrilateral plate is not easy to fixed for thinning bones and adjacent to the articular cavity. The operator should know well about the anatomy and choose the suitable internal fixation. After quadrilateral plate fractures, the femur head maybe displace medially even break into pelvis. That make reduction and treatment always be a challenge. With different kinds of fractures,the efficacy of treatment is not the same. This paper intend to review the relation of anatomic features,approaches, internal fixations, key point of treatment and efficacy.
Acetabulum ; injuries ; surgery ; Animals ; Fracture Fixation, Internal ; instrumentation ; methods ; trends ; Fractures, Bone ; surgery ; Humans

OBJECTIVESTo compare the stability of an enhanced load sharing dynamic pedicle screw fixation device with its equivalent rigid device and to evaluate biomechanical roles of the dynamic fixation.

METHODSA model of L(1) body fracture was produced on seven specimens of fresh adult cadaver spine from T(10) to L(4). Both dynamic and rigid devices were applied in the specimens to strength the injured level. Ranges of three dimensional movements and stiffness under flexion-compression were measured in intact, injured and stabilized specimens.

RESULTSBoth dynamic and rigid devices were found to provide significant stability for injured segment in flexion-extension and lateral bending. In axial rotation, the devices could restore the stability to levels similar to those in an intact spine. Results indicated 40% increase in range of motion in flexion-extension and 24.1 Nmm reduction in stiffness of flexion-compression for dynamic device, compared with the rigid device.

CONCLUSIONThe dynamic device offers a design that may enhance load sharing without sacrificing the stability and will decrease stress-shielding and stress concentration.

Biomechanical Phenomena ; Bone Screws ; Fracture Fixation, Internal ; instrumentation ; Humans ; Male ; Spinal Injuries ; surgery