Abstract: An intrusion detection system for a space secured in part by a deflectable physical barrier includes a cable sensor mounted on the barrier in such manner that it stretches and flexes in response to deflection of the barrier, thereby to produce an output signal representing such movement. A signal processor receives the signal from the coaxial cable and provides an output affirmative signal if the amplitude of the cable signal, within a predetermined frequency range lying below about 30 Hz, exceeds a predetermined level for a predetermined time interval.

Abstract: A power receptacle assembly includes a plurality of AC snap receptacles each having a base containing three insulation displacement connectors and each electrically connected to a female receptacle connector element. A snap-on retainer forces three insulated power conductors into the three insulation displacement connectors causing knife blade edges thereof to displace insulation and electrically connect inner conductor elements of the insulated power conductors. The snap-on retainer of one of the AC snap receptacles also receives three slotted male tab friction fit connectors to electrically connect them to the three power conductors, respectively. The three slotted male tab friction fit connectors are connected to a printed circuit board that interacts with the three power conductors. Each slotted male tab friction fit connector has an elongated slot separating two bifurcated prongs, outer edges of the prongs frictionally engaging inner surfaces of the insulation displacement connectors.

Abstract: The stem of the femoral prosthesis is provided with a slot in the medial narrow side which communicates with a through-bore within the stem adjacent to the collar. In addition, an elastomeric filling is disposed within the through-bore and cooperates with an arch which connects the proximal end of the stem to the collar or neck in order to adapt the resilience of the stem in the proximal zone to the resilience of the cortical bone. The filling may be made of polyurethane or silicone material.

Abstract: Intrusion detection apparatus for use in perimeter security systems and the like is provided with multiple channel signal processing. Each signal processor includes a bandpass filter whose passband is selectable. Each is respectively responsive to sensed movement including vibrations within the associated selected passband. An output affirmative signal is generated if the amplitude of the input signal constituent within the associated frequency range exceeds a threshold level for a predetermined period of time. A logic circuit receives the outputs of all of the signal processors and provides an output alarm signal when a predetermined combination of affirmative signals is received from the signal processors. Such logic circuit preferably works with digital signals obtained by analog-to-digital conversion.

Abstract: The implant may be used as prosthetic replacement for a ligament and/or tendon. The implant has a plurality of discrete longitudinal strands disposed in side-by-side relation with transverse filaments about the strands. Individual sub-zones of the ligament are folded over in a transverse manner about a longitudinal axis of the sub-zone with intermediate zones being in an unfolded state. The intermediate zones may be formed solely of longitudinal strands to enhance flexibility.

Abstract: A prosthetic ligament implant is sheathed at one end in the sock in order to facilitate pulling of the implant through a hole drilled in a bone. The sock is provided with a separable proximal portion which does not envelope the implant and which can be cut off after pulling of the implant through the hole in the bone. With removal of the proximal portion, the remaining textile structure of the sock becomes asunder so that the sock can be readily pulled off from the end of the implant.

Abstract: The acetabular prosthesis includes a metal supporting shell having collar-shaped projections which have tapered cutting edges for penetrating into the osseous tissue of a pelvic bone. The distal portions of the projections are tapered so that plugs of bone can be formed upon penetration of the projections into the osseous tissue. The projections may be filled with bone chips prior to fitting in of a plastic shell within the metal supporting shell. A multi layer metal mesh is provided on the outer surface of the metal shell for promoting fusion. If the overall attachment is not adequate, the projections can be used for insertion and centering of bone screws.

Abstract: The cap for a femur head can be imbedded without the use of cement and includes an outer shell of hemispherical shape so that forces an be transferred in various positions of the joint without any discontinuity in the surface. In addition, an inner shell is secured within the outer shell and is provided with a conically tapered internal surface at the outer edge and an internal self-tapping screw thread for screwing onto a stump of a femur head. The shell also has an internal curved surface for abutting against the stump to inhibit continued threading of the cap onto the stump. Internal cutting rings may also be provided internally of the inner shell for cutting into the osseous tissue of the femur head.

Abstract: The pull-through appliance is made of a mesh structure formed of at least one continuous thread and a pullout thread disposed at one end of the mesh structure to prevent unraveling of the mesh structure. A hollow tube is used to facilitate drawing in of the synthetic strand and autologous strand of the prosthesis. After removal of the hollow member, the resulting package can be readily threaded through a bore in a bone. After implantation, the pull-out thread is removed and the mesh structure unraveled so as to remove the mesh structure from within the bone.

Abstract: A centering element for a shank of a femur bone prosthesis is of three-sided pyramidal shape with an equilateral triangular-shaped base. The apex of the centering element is also rounded while a stud is provided at the base for interfitting in a recess in the prosthesis shank. The shape of the centering element enables insertion of the element together with a shank in a cavity in a bone already filled with bone cement.

Abstract: The ligament anchor is used for fastening an artificial ligament in a bone. The ligament anchor is formed of a clamp sleeve which tapers on the outside and is deformable radially to a smaller inner diameter. The clamp sleeve has projecting saw tooth segments on the inside with steep flanks against the direction of loading for engaging in the inserted ligament. The clamp sleeve is supported by an anchoring sleeve which tapers internally and is inserted in the opening of the bone. For anchoring, the ligament is pulled outwards under pressure against the direction of loading and the clamp sleeve is pressed into the anchoring sleeve in the direction of loading until the saw tooth elements embrace and hold the ligament such that under the built-up pressure and the ligament tension in the direction of loading, self locking of the sleeves take place.

Abstract: A sensor post has a hollow interior and a semi-rigid surface which flexes in response to an applied force. Sensor bars are mounted to the semi-rigid surface in a cantilevered fashion, and include an intermediate electrically insulated section located inside the interior of the sensor post. The sensor element mounting means is rigidly mounted to a portion of the sensor post which remains essentially stationary during an intrusive event. Sensing elements are made of a flexible semi-conductive sensing material, whose resistance increases when the material is stretched, and are mounted so as to straddle an electrically insulated section of the sensor bars. A signal analysis means detects an increase in the resistance of the sensing elements and generates an alarm.

Abstract: A finger joint prosthesis is provided with consists of two pegs of sintered hydroxylapatite for anchoring in adjacent finger bones and which is provided with an intermediate slide layer of polyurethane between the pegs to permit relative movement therebetween. The pegs together with the intermediate layer which may be anchored on one of the pegs form concave and convex bearing areas mating with each other to allow a guided motion in the bend-stretch plane.

Abstract: A femur head prosthesis is provided with a shank body for implanting in a femur and a pair of removeably fastened cheeks which are secured to opposite sides at a proximal end of the shank body. The cheeks can be selected from a kit of different sized cheeks. Also, each cheek has a bulge extending laterally from the shank body. Also, each cheek tapers in conically from lateral to medial and from proximal to distal.

Abstract: The tibial anchoring part is formed of a flat semi-circular bearing element which defines a tibia plateau for receiving a plastic bearing element as well as a blade-like fixing element. This fixing element extends at an incline from ventral to dorsal in a distal direction and has a cutting edge at the dorsal edge for penetrating into the bone. An enlargement is also provided distally of the fixing element to prevent inadvertent pullout of the part and is also provided with a cutting edge at the dorsal edge of the anchoring part.

Abstract: A multi-layered porous wire mesh defining a trough shape is used in association with an artificial acetabulum to strengthen the edge of a hip bone near the main load direction. The porous wire mesh is of trough shape and is filled with compacted fragments of spongy tissue for intimate uniting with the edge of the hip bone.

Abstract: A reference system for the implantation of condylar total knee prostheses comprises a measuring rod (1) parallel to the longitudinal axis of the tibia (T) having at least two attachment arms (2) for lateral attachment to the outside of the tibia (T), a guide rail (9) connected to the measuring rod having a measuring scale (10) thereon and an adjustable measuring carriage (11) to which a cutting block (15) for performing the necessary osteotomies is affixed for movement in two directions so that cutting block can be displaced and fixed in such a way that by slots therein, the osteotomy can be carried out at the right place. For determining the position, there is attached to the measuring rod an alignment bar (20) which forms the continuation of the measuring rod toward the pelvis and has a length such that the end reaches to the pelvis.

Abstract: The plastic cup-comprising member and the hemispherical shell of the two-part acetabular cup prosthesis are secured relative to one another in snap-fitted manner. The plastic member is centered and guided during pressing-in via a centering pin and concentric annular web on the plastic member. The annular web is also locally deformable so as to deform against a screw head during pressing-in without the annular web losing its centering guiding action.

Abstract: The reinforcement is formed of a peg from which a plurality of flaps extend with slots formed between adjacent flaps. The flaps serve to separate a bone cement bed within the interior of the reinforcement from a layer of a compacted spongy tissue externally of the reinforcement. The slots between the flaps extend over the entire height of the reinforcement and permit substantial spreading or widening of the flaps radially in order to adapt to the individual operation cavity and to anchoring stems of different cross-sectional sizes and shapes.

Abstract: The external surface of the hip joint socket is provided with a contrast ring in a diametric plane of the joint head receiving cavity as well as with a metallic measuring ring in the upper surface of the socket body. The measuring ring is concentric to the axis of rotation of the body and is parallel to the plane of the contrast ring. By measuring the distance of the two metallic rings from each other in an X-ray picture, a determination can be made as to whether a displacement of the center of the spherical joint head is due in part to a cold flow of the socket material or exclusively to abrasion.