70 results about "Distal radius fracture" patented technology

Methods and devices for treating fractures in or adjacent the wrist and distal forearm employ an intramedullary interlocking fixation rod (i.e, it interlocks the distal and proximal fracture fragments together) to stabilize the skeletal structure in a manner which can inhibit the amount of collapse or loss in skeletal length exhibited by a patient with a distal radius fracture.

Medical kits for treating fractures in or adjacent the wrist and distal forearm employ an intramedullary interlocking fixation rod (i.e, it interlocks the distal and proximal fracture fragments together) to stabilize the skeletal structure in a manner which can inhibit the amount of collapse or loss in skeletal length exhibited by a patient with a distal radius fracture.

A distal radius plate according to the invention is ergonomically formed to be more easily centered on the radius bone. The distal radius plate has two main portions: an elongated portion that attaches to the body of the radius and a distal radius portion that attaches to the lower most, wider portion of the radius bone. Because of its ergonomic shape the distal radius plate is fast and easy to center on the radius and install. In another embodiment, the distal radius plate may include a metal support that is partially or entirely covered with a plastic to eliminate or reduce detailed machining of the metal, which reduces part cost and manufacturing time.

The present invention relates to the field of orthopedic medical device technology, in particular to a functional distal radius fracture combined fixator. A spherical joint spring structure, which consists of a circumflex spring ball end, a circumflex spring rod, a spring, an internal and external threaded ball end bowl, a lock-pin sliding block with a sliding slot on the two sides and a ball bowl top wire, provides the conditions for the wrist joint multi-directional and multi-angle moving range and the flexibility; the combined application of an external hexagonal ball bowl, a ball bowl fastening cap, a ball bowl rod and an open lock pin with a T-shaped lock pin structure provides the conditions for the optimal selection between the longitudinal penetration of two screw threaded pins into a second metacarpus or the horizontal penetration of one screw threaded pin into a second metacarpus and a third metacarpus; an angle-regulating stable structure, which comprises a semispherical geared latch, a semispherical geared left and right wire nut, a left and right screw threaded adjusting rod, a left and right wire nut pin and a left and right threaded nut can fix the wrist joint in a certain angle according to the clinical needs, thus greatly facilitating the angle-oriented fixation, achieving the stable fixing effect and bringing a lot of convenience to the operation and preliminary function activities of the wrist joint.

The invention discloses an auxiliary repositor for distal radius fracture. The auxiliary repositor comprises an L-shaped elbow joint supporting plate, a horizontal supporting plate, a slideable waist joint supporting plate and a hand sliding fixing handle. An arm of a patient is subjected to elbow flexion by 90 degrees and then is put on the L-shaped elbow joint supporting plate, and an upper arm and a front arm are fixed on the L-shaped elbow joint supporting plate through an upper arm bandage and a front arm bandage respectively; the patient holds the hand sliding fixing handle with fingers, and a hand is fixed by a self-adhesion bandage; an adjusting bolt is rotated, and the slideable waist joint supporting plate moves away to achieve the effect of fracture site pull-out; then the hand sliding fixing handle is moved in an arc-shaped sliding groove, so that the arm reaches a palmer flexion or dorsiflexion angle needed for fracture stabilization; a fixed bolt is screwed, so that the hand sliding fixing handle is fixed. The auxiliary repository has a simple structure, is low in manufacturing cost, convenient to operate, stable in traction in the restoration process, and ideal in restoration effect, avoids redisplacement had, and meanwhile, reduces the working intensity and difficulty of medical staff.

Provided is a locking plate system for treatment of a distal radius fracture, including a locking plate (4) that is a flat laminate of intermediate molding materials that includes carbon fibers as a reinforcing material and thermoplastic resin as a matrix; a screw anchor (5) having a shaft portion (10) which has a principal thread (13) achieving a self-tapping action formed thereon and an outer circumference of a head portion of the screw anchor (5) which has an auxiliary thread (13) achieving a self-tapping action tapped thereon; and a through-hole (6) in the radius locking plate (4), which allows the radius main body (3) and the fractured bone piece (2) to be threadably fixed to the radius locking plate (4) and having a diameter that is oversized relative to the principal thread (11), and that is undersized relative to the auxiliary thread (13).

The invention discloses a finger traction reduction fixation splint which is mainly used for distal radius fracture reduction fixation. After manual reduction of distal radius fracture is finished, the finger traction reduction fixation splint can be rapidly mounted, fracture reduction can be effectively maintained, wrist fracture can be further reduced by the ligament reduction principle after finger traction, the height of a distal radius joint surface is kept, traction directions can be adjusted and lateral displacement can be corrected according to situations, all joints of hands can be functionally trained based on reduction maintenance, detumescence is promoted, hand functions of a patient are reserved as far as possible, and rehabilitation effects are ensured. Besides, the finger traction reduction fixation splint is also applicable to treatment of metacarpal fracture, phalangeal fracture and wrist fracture dislocation.

An activity-inertia combined adjusting control outer fixer for a distal radius fracture is formed by an outer fixer frame body, steel needle fixing clamps connected onto the outer fixer frame body and steel needles clamped in the steel needle fixing clamps; the outer fixer frame body comprises a far end hole arc ring and a near end hole arc ring, which are arranged in parallel, have the same opening directions and are provided with multiple uniformly distributed holes respectively; a first thread connection rod is connected to the far end hole arc ring; the far end hole arc ring and the near end hole arc ring are connected by at least two second thread connection rods penetrating the holes; the far end hole arc ring, the first thread connection rod and the second thread connection rods are connected with the steel needles by the steel needle fixing clamps. The activity-inertia combined adjusting control outer fixer can be used for the reset of the distal radius fracture, and can perform joint-crossing fixing or local fracture fixing according to different treatment periods, thus more according with the anatomic and therapeutical demands of the distal radius fracture. The activity-inertia combined adjusting control outer fixer is suitable for treatment of various radius fractures, particularly, the opening distal radius fracture or a severe comminuted fracture.

The invention discloses a distal radius fracture fastener with an angle correcting structure, relates to a device for treating bones or joints, and in particular relates to a distal radius fracture fastener with an auxiliary correction function when an internal fixer is implanted. The distal radius fracture fastener comprises a bone plate and a plurality of locking screws. The distal radius fracture fastener is provided with the angle correcting structure and takes the bone plate as a lever. A fulcrum nail arranged at the far end of a rod part of the bone plate serves as a fulcrum, a support pad component is arranged at the proximal end of the rod part of the bone plate for adjusting an angle of the bone plate, so that the head part of the bone plate is bonded with a fragment fracture, and the locking screws arranged at the head part of the bone plate are far away from an articular cartilage surface of a distal radius. The support pad height of the support pad component is adjusted in a process of implanting the bone plate to effectively prevent the locking screws at the far end from from breaking through the articular cartilage surface so as to enter an articular cavity, so that the risk of fixation failure is reduced, and a palm tilt is accurately recovered through the angle correcting structure to shorten an operation time and provide the angle stability for fracture.

The invention relates to a plate for stabilizing distal radius fractures, comprising an elongated stem (1) and anatomically pre-shaped distal plate (5) connected to it, wherein the plate The envelope has a substantially triangular shape; it also includes threaded holes provided in the stem and in the distal plate, at least on the distal plate, in a tapered configuration with a threaded longitudinal axis, each threaded longitudinal axis at The distal plate is mainly distributed non-parallel and a bend (6) is formed between the stem and the plate. According to the invention, the triangular shape of the plate or the corresponding envelope is scalene, wherein the side of the triangle facing away from the shaft has a number of conical threaded holes. The diameter of these tapered threaded holes is chosen to be smaller than the diameter of the screw holes in the shank, and the longitudinal axes of the threads of the plurality of holes in the plate form an angle different from 90° to the surface of the shank.

The invention relates to a fixing tool used after distal radius fracture reduction in the medical field, in particular to a distal radius integrated splint (integrating splints, pressing pads and strapping tapes). A cotton pressure pad is additionally arranged at the far end of a back side plate, and the angles of the back side plate, a radial side plate and an ulnar side plate are changed into adjustable angles of application pressure pads. Four horizontal holes are formed in the side surface of each splint, cotton strapping tapes penetrate through the splints respectively to connect the splints into a whole, a thin cotton pressing pad with the position capable of being adjusted at will is bonded to the inner side surface of the radial side plate and the inner side surface of the back side plate, and the splints and the pressurizing cotton pads are bonded into a whole. The problems that parts of a traditional splint are scattered and need to be operated by multiple persons, the pressurizing cotton pads and the strapping tapes need to be temporarily manufactured by doctors, an anaphylactic reaction is caused due to the fact that the pressing pads or the strapping tapes stimulate the skin, pressing of the fractured end of a fracture is uneven, and pressing pad movement and fracture displacement are prone to occurring are solved; and the problems that a traditional splint is inconvenient to adjust and dress repeatedly, and is inconvenient to carry and use at any time can be solved.

The invention provides an ointment for synthetism used for treating distal radius fracture, which comprises the following raw materials by weight part: 2 parts of radix aconite, 2 parts of radix aconiti kusnezoffii, 4 parts of raw pinellia ternate, 6 parts of raw rheum officinale, 5 parts of levisticum, 5 parts of notopterygium root, 5 parts of sappan wood, 10 parts of ground beeltle, 5 parts of rhizoma drynariae, 5 parts of lumbricus, 3 parts of cortex acanthopanacis, 3 parts of saffron, 5 parts of Gardenia jasminoides, 5 parts of radix paeoniae rubrathe, 5 parts of sophora flavescens, 5 parts of Chinese angelica, 5 parts of speranskia herb, 4 parts of Gentiana macrophylla, 4 parts of Strychnos nuxvomica, 4 parts of Syngnathus schlegeli, 4 parts of sea horse, 4 parts of petrel, 3 parts of Tabanus bivittatus Matsumura, 3 parts of whole worm, 2 parts of Xi Niuhuang, 1 part of natural musk, 3 parts of borneol, 3 parts of camphor, 3 parts of frankincense and 3 parts of myrrh. The ointment for synthetism can be used for treating damaged disease tissues which lacks of exercise, the disease tissues can be re re-excited and regenerated, and restoration and reconstruction of the damaged can be completed.

The present invention relates to a device for internal fixation of the bone fragments (2, 3) in a radius fracture (4). The device comprises at least one body (1) for abutment against the bone fragments (2, 3) in the radius fracture (4), and fixing elements (6, 7) which are intended to be locked to the body for fixation of said bone fragments. The body (1) itself has in a distal end portion (1a) at least two predrilled holes (8) for fixing elements (6), and in a proximal end portion (1b) at least two predrilled holes (9) for fixing elements (7). To allow effective optimum internal fixation of the bone fragments in the radius fracture, the predrilled holes (8, 9) run obliquely relative to a longitudinal axis (L) of the body (1) so that all of the fixing elements (6, 7) which, after the body has been caused to abut against the bone fragments (2, 3) in the radius fracture (4), are introduced into said bone fragments through holes (8, 9) in the body's distal end portion (1a) and proximal end portion (1b) cross the radius fracture (4) as viewed in the transverse direction of the body. Each fixing element (6, 7) has at least one fixing portion (10; 10a, 10b) for locking the fixing element in the bone fragments (2, 3) in the radius fracture (4) and for locking the fixing element to the body (1).

An external fixator for a fractured distal radius including a first plurality of vertical passages for pins extending downward from a first pin mounting block into one or more bone fragments and one or more frame element apertures extending from an elongated frame element for pins extending downward from the device into the shaft of the radius. In addition, the elongated frame element includes a sliding pin slot with a sliding structure allowing a single pin to be moved to provide extension between the fragments and the shaft. A sliding internal plate including holes aligned with the first plurality of vertical passages is moved by a pair of setscrews to clamp the pins extending through the first plurality of vertical passages. The device also includes a second pin mounting block that extends downward parallel to the pins extending from first pin mounting block to hold pins directed laterally into the fragment(s).

The invention discloses an external fixation treatment device for distal radius fracture. The external fixation treatment device for the distal radius fracture comprises a forearm palmar splint for attaching to and fixing the palm side of the forearm of a patient, an inner side splint, an outer side splint, a forearm dorsal splint for attaching to and fixing the upper side of the forearm of the patient, wherein the inner side splint and the outer side splint are used for attaching to and fixing the inner side and the outer side of the forearm of the patient. The forearm palmar splint, the inner side splint, the outer side splint and the forearm dorsal splint are bound on the periphery of the forearm of the patient so as to fix strip-shaped components of the hand and the forearm circumferentially. The external fixation treatment device further comprises a palm cover for wrapping the palm of the patient and elastic inserting strips for performing flexible limit and extension on the forearm relative to the wrist joint of the patient. The elastic inserting strips are respectively connected between the palm cover and the forearm dorsal splint, the palm cover and the inner side splint, the palm cover and the outer side splint and the palm cover and the outer side of the forearm palmar splint.

The invention relates to the technical field of medical devices, and particularly to a device for reduction of distal radius fractures. The device comprises a support plate and a U-shaped column. TheU-shaped column is inversely fixed at one end of the support plate, and the other end of the support plate is provided with a fixing belt. The inner side of the top end of the U-shaped column is connected with a traction frame through a screw A, and the traction frame is provided with a finger sleeve. In the application process of the invention, the elbow of the arm is bent 90 degrees, the upper arm is fixed on the support plate by a fixing belt, the index finger and the middle finger are suspended under the lower plate by a finger sleeve, and the lifting height of the index finger and the middle finger is adjusted through a screw A, a screw B and a nut, so as to indirectly reduce the fracture of the distal end of the radius; Moreover, the bar-shaped through-hole groove is mainly arrangedto facilitate the moving operation of the screw A and the adjustment of the position of the traction frame when the medical staff operates. The device has the advantages of simple structure, convenience and practicability, and can be operated by one person, thereby reducing unnecessary human waste of medical personnel.

A needle-type locking osteosynthesis plate nail system structure for radius distal fracture includes an implantation needle, a compression fixing needle, a bent part, a compression plate, locking screws and a cortical bone screw; the implantation needle is connected with the compression fixing needle through the bent part; a compression part has a ''U'' structure, and the tail end of the compression part is in the shape of an arc; the compression plate is arranged on both arms of the compression part, and the compression plate is provided with an inverted cone-shaped fixing groove to simultaneously press both arms of the compression part; and screw holes are arranged in the compression plate, and the locking screws and the cortical bone screw pass through the screw holes to pressurize andfix a bone block. The needle-type locking osteosynthesis plate nail system structure reduces ligament peeling during surgery, has smaller damage to a patient, reduces the pain of the patient, and cangreatly shorten the recovery period of the patient; and the needle-type locking osteosynthesis plate nail system structure also reduces the difficulty of bone reduction, improves the success rate of the surgery, and is more convenient for clinical operation.

The invention discloses a wrist joint functional exercise precision measurement device which comprises a base. A glove device is mounted at the front end of the base through a rope, and hand back surfaces or palm surfaces of a pair of gloves of the glove device are in opposite connection through a clamping device or adhesives. Binding plates are mounted at the upper end of the base through second hinge shafts, and binding holes for mounting binding strings are integrally formed in outer sides of the binding plates. The device has advantages that the problem of poor exercise effects caused by the fact that many patients suffering from distal radius fracture neglect exercise due to fear of postoperative pains or cannot direct link exercise degrees and effects in each time due to lack of guidance of professionals can be solved, progress degrees of each exercise mode can be effectively assisted and quantitatively measured, an exercise process is planed reasonably, and accordingly postoperative rehabilitation exercise effects can be improved.

The invention discloses a Yao-nationality medicine for treating fracture of distal radius. According to the Yao-nationality medicine, different prescription combinations are adopted for different phases of fracture, swelling pain of an affected limb can be relieved at the early phase, fracture healing can be promoted at the medium phase, and affected wrist functions can be improved at the late phase, so that occurrence of complications after fracture can be effectively reduced.

The invention relates to an external fixation locking fixing device for treatment of fracture of distal radius, belonging to the technical field of medical instruments. The locking external fixation device comprises a frame body and screws, the frame body comprises a T-shaped fixing part and a strip-shaped fixing part, the T-shaped fixing part and the strip-shaped fixing part are uniformly provided with threaded holes, the threaded holes are matched with threads of the tail parts of the screws so as to enable the T-shaped fixing part to be fixed on a back side bone block of the distal radius, and the strip-shaped fixing part is fixed on the radius side of the distal radius so as to enable the fracture of the distal radius to realize diaplasis locking. By using the locking external fixation device, the trauma is small, the hemorrhage is less, the incision is reduced manifold, and the cicatrix is small and attractive; and the operative complications are obviously reduced. Taking out by second operation is not required, so that hospitalization costs are saved for a patient. Moreover, the locking external fixation device is light in weight, the patient suffering from less pain, and the locking external fixation device is conducive to rehabilitation of the patient. According to the locking external fixation device, the screw path injury is small, the screw path complications are fewer, and the operative safety is improved; and as the fixation does not cross a joint, the operative interference with the wrist joint is reduced.

The invention provides a distal radius fracture reducer and relates to the field of medical equipment. The distal radius fracture reducer comprises a first workbench and a second workbench, wherein aside wall of the first workbench is fixedly connected with the second workbench; a plurality of fixed limiting rods are fixedly arranged on the upper end surface of the first workbench; a plurality ofmovable grooves are formed in an inner end of the first workbench; one movable limiting rod is arranged at the inner end of each movable groove; the upper end of each movable limiting rod penetratesthrough the corresponding movable groove to an outer end; a threaded hole is formed in the bottom end of each movable limiting rod; and the inner end of each threaded hole is in threaded connection with a screw. The reducer provided by the invention can stably fix an arm and wrist of a patient, and meanwhile, a single doctor can easily and accurately complete reduction of a radius fracture of thepatient through operating a first rotating handle and a second rotating handle, so that manpower is saved, meanwhile, the labor intensity is reduced and the reduction success rate is increased.

The invention relates to a treatment method for promoting healing of distal radius fracture. Manipulative reduction is performed by means of Zhuangjin bugu pills, small splints are used for external fixation, and medicines for external application are not required. After fracture reduction and fixation, a patient orally takes Zhuangjin bugu pills ((2001) approval number 3P-066, Food and Drug Administration of Shenzhen Municipality) three times one day, 6 g of the pills are taken each time, and the patient needs to take the pills for 21 d continuously and cannot take other internal medicines; the tightness of a bandage tied on the splints is adjusted once every three days in one week after fracture reduction and fixation, and afterwards, the tightness is adjusted once every week until the splint fixation is removed after clinic healing of fracture. The tightness of the bandage tied on the splints is adjusted in the standard that the tied bandage can move up and down for 1 cm.

The invention discloses a non-transarticular external fixator for treating a distal radius fracture. The non-transarticular external fixator comprises two main radius nails, a portal frame, a first connecting rod, a second connecting rod, a third connecting rod and a plurality of penetrating fixation needles. The upper ends of the main radius nails are connected to the first connecting rod throughnail rod clamps, the transverse part of the portal frame is connected to the front end of the first connecting rod through a rod-rod clamp, and both ends of the second connecting rod are respectivelyconnected to one longitudinal part of the portal frame and the first connecting rod respectively through rod-rod clamp, both ends of the third connecting rod are respectively connected to the other longitudinal part of the portal frame and the first connecting rod through rod-rod clamps, and both ends of each penetrating fixation needle are connected to two longitudinal parts of the portal framerespectively trough needle rod clamps. The non-transarticular external fixator has the advantages that when the external fixator is used for a non-transarticular surgery, wrist joints and fingers of apatient can move unrestrictedly and move immediately and bear part of functions, so that the comfort level of the patient is improved, the life burden on the patient is reduced, and the recovery process is accelerated.

The invention discloses an automatic reduction device for distal radius fracture. The automatic reduction device comprises a movable base, a lifting type arm fixing bearing table, a lifting type supporting table, a horizontal moving type traction pressing mechanism and a horizontal moving type traction palm flexion angle adjusting table; the bottom end of the lifting type arm fixing bearing table is fixedly connected with one side of the top end of the movable base; the bottom end of the lifting type supporting table is fixedly connected with the other side of the top end of the movable base; the bottom end of the horizontal moving type traction pressing mechanism is slidably connected with the top end of the lifting type supporting table through a first driving mechanism in the traction direction, an arc-shaped sliding rail is arranged at the top of the horizontal moving type traction pressing mechanism, and a plurality of pressing correction push rod mechanisms are slidably connected to the arc-shaped sliding rail; a pressure sensing probe is fixed at the pressing end of each pressing correction push rod mechanism; the bottom end of the horizontal moving type traction palm flexion angle adjusting table is in sliding connection with the bottom of the horizontal moving type traction pressing mechanism through a second driving mechanism in the traction direction, and the top end of the horizontal moving type traction palm flexion angle adjusting table is connected with the top end of the lifting type arm fixing bearing table. The device is simple in structure, high in safety and capable of achieving accurate traction reset.

A retractor for distal radius fracture reduction and shoulder joint dislocation, which includes two first retractor main rods (5) and second retractor main rods (9) connected at one end by ball joints, the first retractor main rod (5), the other end of the main rod of the second tractor (9) is provided with threads, and the finger nuts (4) and elbow nuts (10) are respectively installed on the threads, and the finger nuts (4) are connected There is a finger support pole (6), and a fixed frame (11) is installed on the upper end of the finger support pole (6), and a finger clamp tractor (2) is installed on the fixed frame (11); on the elbow support nut (10) An elbow rest (7) is installed, a wrist rest (8) is movably installed on the first retractor main rod (5) or the second retractor main rod (9), and locking screws ( 1). It has the advantages of simple use and operation, good patient compliance and tolerance, and can be independently completed by a single person for all fixation and traction work. At the same time, it also has the characteristics of simple production and maintenance, low cost, durable and easy to popularize.

The invention discloses a wrist clamping device for a distal radius fracture reduction robot. The wrist clamping device mainly comprises a front wrist clamping mechanism, a rear wrist clamping mechanism and a rack, wherein the front wrist clamping mechanism and the rear wrist clamping mechanism are the same in structure. The two wrist clamping mechanisms are used for clamping, fixing and supporting the wrist of the patient in the reduction operation process and assisting a doctor in fixing the forearm plaster of the patient in an alternate lifting mode after reduction is finished. The two wrist clamping mechanisms are mounted on the rack, and the rack is mounted on a reduction robot used for assisting a doctor in performing a distal radius fracture operation. The wrist clamping device can adjust the clamping width to adapt to arms of patients with different physiques, is convenient to use, and can remarkably reduce the workload of doctors and improve the success rate of an operation.

Disclosed is an external fixation system for a distal radius fracture. The system comprises an external fixation locking plate, at least four locking sleeves which are matched with the external fixation locking plate, a plurality of metal guide needles which are matched with the locking sleeves and a plurality of hollow screws which are matched with the metal guide needles and the external fixation locking plate. The external fixation system for the distal radius fracture is characterized in that a non-joint integrated type external fixation mode is adopted, the situation is avoided that the joint is not stable in an existing external fixation apparatus; the external fixation locking plate adopts an L-shaped plate type structure to be able to conduct three-dimensional fixation on the two ends of the fracture and improve stability; the direction of the external fixation locking plate and the direction of screw locking holes in the external fixation locking plate are designed according to the anatomical morphology of the distal radius, which is special for the direct fixation of the two ends of the distal radius and different from the indirect fixation of an existing external fixation bracket; the locking sleeves extend a fixed distance in the inner side of the external fixation locking plate, the distance between the external fixation locking plate and the skin of a patient can be limited, and the operation is simpler and more standard; the external fixation system for the distal radius fracture has the effects of internal fixation and external fixation.

The invention discloses a distal radius fracture wrist fixation protection tool. The distal radius fracture wrist fixation protection tool comprises a fore arm binding mechanism, a TDOF (Two-Degree of Freedom) mechanism and a palm binding mechanism which are sequentially connected in a fore arm direction, wherein the fore arm binding mechanism comprises an upper clamping plate for fore arm fixation, a rear restraint strap for fore arm fixation and a lower clamping plate for fore arm fixation, the rear restraint strap for fore arm fixation is fixed to the upper clamping plate for fore arm fixation, and the lower clamping plate for fore arm fixation is connected with the upper clamping plate for fore arm fixation by virtue of the restraint strap; the palm binding mechanism comprises a hand back fixation clamping plate, a palm fixation restraint strap arranged on the hand back fixation clamping plate and a palm fixation clamping plate connected with the hand back fixation clamping plate through the restraint strap; the TDOF mechanism comprises a rotary joint pedestal connected with the upper clamping plate for fore arm fixation, an ulnar-deviation radial-deviation rotary joint connected with the hand back fixation clamping plate, and a palm-inclination back-extending rotary joint arranged between the rotary joint pedestal and the ulnar-deviation radial-deviation rotary joint. The distal radius fracture wrist fixation protection tool is capable of replacing gypsum, achieving an effect of fixing a wrist of a patient suffering from distal radius fracture, and improving certain defects of gypsum fixation.