1、BRITISH STANDARD BS3531-5.4: 1993 ISO9268:1988 Implants for osteosynthesis Part 5: Bone screws and auxiliary equipment Section5.4 Specification for screws having symmetrical and asymmetrical thread and conical under-surfaces UDC 621.882.2:616-089BS3531-5.4:1993 This British Standard, having been pre
2、pared under the directionof the Health Care Standards Policy Committee, waspublished under the authorityof the Standards Boardand comes into effect on 15 May1993 BSI 08-1999 First published May1990 Second edition May1993 The following BSI references relate to the work on this standard: Committee ref
3、erence HCC/22 Draft for comment87/50451 DC ISBN 0 580 22153 9 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Health Care Standards Policy Committee (HCC/-) to Technical Committee HCC/22, upon which the following bodies were represented:
4、 Association of British Health-care Industries British Institute of Surgical Technologists British Investment Casting Trade Association British Medical Association British Orthopaedic Association British Steel Industry British Surgical Trades Association Department of Health Institute of Sterile Ser
5、vices Management Medical Sterile Products Association National Association of Theatre Nurses Royal College of Surgeons of England Royal Veterinary College Scottish Office Amendments issued since publication Amd. No. Date CommentsBS 3531-5.4:1993 BSI 08-1999 i Contents Page Committees responsible Ins
6、ide front cover National foreword ii 0 Introduction 1 1 Scope and field of application 1 2 Reference 1 3 Code for screw thread 1 4 Dimensions and tolerances 1 5 Marking and packaging 7 Annex A Interrelationship of International Standard dealing with bone screws, bone plates and relevant tools 8 Anne
7、x B Bibliography: International Standards referred to in table of Annex A 9 Figure 1 Screw with single-slot recess 2 Figure 2 Screw with cruciate recess 3 Figure 3 Screwhead with combined cruciate-slot and cross-recessed drive connection 4 Figure 4 Illustration of HC thread form 4 Figure 5 Screw wit
8、h cross-recessed head 5 Figure 6 Asymmetrical thread HD 6 Figure 7 Cross-recessed drive connection 7 Table 1 Dimensions of screw with single-slot recess 2 Table 2 Dimensions of screw with cruciate recess 3 Table 3 Dimensions of symmetrical thread HC 5 Table 4 Dimensions of screw with cross-recessed
9、head 5 Table 5 Dimensions of asymmetrical thread HD 6 Table 6 Dimensions of cross-recessed drive connection 7 List of references Inside back coverBS3531-5.4:1993 ii BSI 08-1999 National foreword This Section of BS3531 has been prepared under the direction of the Health Care Standards Policy Committe
10、e. It is identical with ISO9268:1988 Implants for surgery Metal bone screws with conical under-surface of head Dimensions, published by the International Organization for Standardization (ISO) and supersedes BS3531-5.4:1990 which is withdrawn. Requirements for orthopaedic implants (then termed “surg
11、ical implants”) were first published in1962 as BS3531. In1968 a part revision of BS3531:1962 was issued as BS3531-1, which dealt with surgical implants made of all materials. In1980 the first four Parts of a multi-Part version of BS3531 were published. A further19 Parts of BS3531 were subsequently p
12、ublished. BS3531-5 was first published in1982 and gave requirements for particular types of bone screw, for taps, drills and screwdrivers, and for holes and slots in bone plates. The revision of BS3531-5 offered the opportunity to facilitate the implementation of published and forthcoming Internatio
13、nal Standards, and to separate, in different Parts of BS3531, requirements for screws and auxiliary equipment from those for bone plates. Requirements for bone screws and their auxiliary equipment are retained in BS3531-23, also published in Sections. BS3531-5:1982 has been withdrawn. BS3531 now onl
14、y covers implants for osteosynthesis, BS7251 covers joint prostheses, BS7252 covers metallic materials for surgical implants, BS7253 covers non-metallic materials for surgical impants, i.e.aspects common to osteosynthesis and joint replacement. BS3531-5.4 was first published in1990 and specified dim
15、ensions, tolerances, materials and mechanical properties for bone screws of nominal sizes4mm,3.5mm and3mm. This revision of BS3531-5.4 now specifies only the dimensions and tolerances for bone screws of nominal sizes4.5mm,4.2mm,3.9mm and2.9 mm. Mechanical properties are specified in BS3531-5.6. The
16、screws specified in this Section of BS3531 are suitable for use with the screwdrivers specified in BS3531-5.2 and for use with the taps and drills specified in BS3531-5.5, and will fit with the holes and slots in bone plates specified in BS3531-23.2. It is strongly recommended that the products spec
17、ified in this Section of BS3531 should be manufactured according to the recommendations given in Quality Systems for Orthopaedic Implants1990 Good Manufacturing Practice 1) . Product certification. Users of this British Standard are advised to consider the desirability of third party certification o
18、f product conformity with this British Standard based on testing and continuing product surveillance which may be coupled with assessment of a suppliers quality systems against the appropriate Part of BS5750. Cross-references International Standard Corresponding British Standard ISO6018:1987 BS7254
19、Orthopaedic implants Part1:1990 Specification for marking, packaging and labelling (Identical) 1) Compiled by the Department of Health; published and available from HMSO,49 High Holborn, London WC16HB for personal callers, or by post from HMSO, PO Box276, London SW85DT.BS3531-5.4:1993 BSI 08-1999 ii
20、i Enquiries as to the availability of third party certification schemes are forwarded by BSI to the Association of Cerfication Bodies. If a third party certification scheme does not already exist, users should consider approaching an appropriate body from the list of Association members. A British S
21、tandard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cov
22、er, an inside front cover, pagesi to iv, pages1to10, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.iv blankBS3531-5.4:1993 BSI 08-1999 1 0 In
23、troduction This International Standard lays down requirements for surgical bone screws as given in the Scope. It is necessary to bear in mind that there may be a need for bone screws for particular applications, which are not covered by this Standard or by ISO5835. Such special bone screws may diffe
24、r in part from the standardized forms or may combine parts from these two product Standards. However, there are certain areas of the design of screws such as the drive connections, the shape of the under-surface of the head and the thread form that are critical from the point of view of use in surge
25、ry. These areas are those in which there is an interface with bone plates (ISO9269) or other devices or with instruments such as screwdrivers (ISO8319-2) or taps, drills and countersink cutters. No variation is permitted in these areas. 1 Scope and field of application This International Standard sp
26、ecifies the dimensions and tolerances of metal bone screws with conical under-surface of the head used in surgery. NOTEThe interrelationship of International Standards dealing with bone screws, bone plates and relevant tools is shown for information in Annex A. 2 Reference ISO6018:1987, Orthopaedic
27、implants General requirements for marking, packaging and labelling. 3 Code for screw thread The following code shall be used to identify the type of screws complying with this International Standard: 4 Dimensions and tolerances 4.1 Screws with symmetrical thread form HC 4.1.1 Screws with single-slot
28、 drive connection Screws with single-slot drive connections shall be as given in Figure 1 and Table 1. Type of thread Code Symmetrical thread HC Asymmetrical thread HDBS3531-5.4:1993 2 BSI 08-1999 Table 1 Dimensions of screw with single-slot recess Figure 1 Screw with single-slot recess Dimensions i
29、n millimetres Type of thread a Nominal diameter d 1 d 2 g h r 2 x max. degrees HC 2,9 4,62 to6,1 1,25 to1,4 1,5 to2 5 1,6 Optional: for example W 60 a See Table 3.BS3531-5.4:1993 BSI 08-1999 3 4.1.2 Screws with cruciate-slot drive connection Screws with cruciate-slot drive connection shall be as giv
30、en in Figure 2 and Table 2. Table 2 Dimensions of screw with cruciate recess Figure 2 Screw with cruciate recess Dimensions in millimetres Type of thread a Nominal diameter d 1 d 2 g h r 2 x max. degrees HC 3,5 3,9 4,2 5,8 to6,5 1,25 to1,4 1,5 to2 6,35 1,6 Optional: for example W 60 a See Table 3.BS
31、3531-5.4:1993 4 BSI 08-1999 4.1.3 Screws with combined cruciate-slot and cross-recessed drive connection NOTEThis cross-recessed drive connection is also called a “modified Philips drive”. The combined cruciate-slot and cross-recessed drive connection shall be as given in Figure 3 and the dimensions
32、 of the head and screw shall be as given in Table 2. 4.1.4 Dimensions of symmetrical thread form HC Dimensions of the HC thread shall be as given in Figure 4 and Table 3. Suitable flutes may be added to make the screws self-tapping. Figure 3 Screw head with combined cruciate-slot and cross-recessed
33、drive connection Figure 4 Illustration of HC thread formBS3531-5.4:1993 BSI 08-1999 5 Table 3 Dimensions of symmetrical thread HC 4.2 Screws with asymmetrical thread form HD 4.2.1 Screws with combined single-slot and cross-recessed drive connection NOTEThis cross-recessed drive connection is also ca
34、lled a “modified Phillips drive”. Screws with combined single-slot and cross-recessed drive connection shall be as given in Figure 5 and Table 4. The slot shall extend into the cylindrical point of the head, but shall not be so deep as to extend into the conical under-surface. The maximum depth of t
35、he recess shall be such that the torque strength of the screw is unaffected. Table 4 Dimensions of screw with cross-recessed head Dimensions in millimetres Code and nominal diameter of thread d 1 d 5 P c min. max. min. max. max. HC2,9 2,79 2,9 2,03 2,18 1,06 HC3,5 3,43 3,53 2,51 2,64 0,1 HC3,9 3,78
36、3,91 2,77 2,92 1,27 HC4,2 4,09 4,22 2,95 3,25 NOTESuitable flutes may be added to make the screws self-tapping. Figure 5 Screw with cross-recessed head Dimensions in millimetres Type of thread Nominal diameter a d 1 d 2 g x max. h degrees HD 4 4,5 6,75 to7,35 1,25 to1,4 1,6 1,8 to2,1 Optional: for e
37、xampleW 60 a See Table 5.BS3531-5.4:1993 6 BSI 08-1999 4.2.2 Dimensions of asymmetrical thread form HD Dimensions of the HD thread shall be as given in Figure 6 and Table 5. Suitable flutes may be added to make the screws self-tapping. Table 5 Dimensions of asymmetrical thread HD Figure 6 Asymmetric
38、al thread HD Dimensions in millimetres Code and nominal diameter of thread d 1 0,03 d 5 0,03 e P r degrees degrees HD4 4 2,92 0,1 1,59 45 10 HD4,5 4,5 2,18 NOTESuitable flutes may be added to make the screws self-tapping.BS3531-5.4:1993 BSI 08-1999 7 4.3 Cross-recessed drive connection The cross-rec
39、essed drive connection shall be as given in Figure 7 and Table 6. NOTEThe heads of screws with this drive connection should be of sufficient size to ensure that the torque strength is unaffected. Table 6 Dimensions of cross-recessed drive connection 5 Marking and packaging Marking and packaging shal
40、l be in accordance with ISO6018. Figure 7 Cross-recessed drive connection Dimensions in millimetres d b max. n 5 3,8 1,4BS3531-5.4:1993 8 BSI 08-1999 Annex A Interrelationship of International Standard dealing with bone screws, bone plates and relevant tools (This annex does not form an integral par
41、t of the Standard.) It has been decided that the set of International Standard dealing with bone screws, bone plates and relevant tools should be divided into two parallel series. The basis of the division into two series is the essentially different designs of the screw threads of the bone screws (
42、HA and HB type screws as opposed to HC and HD type screws). A simplified schematic guide illustrating the interrelationship between screws, plates and tools covered by the two parallel series of International Standards is given below. Screws Thread Head under-surface Drive connection Mechanical requ
43、irements ISO6475 Breaking torque/angle of rotation In preparation Plates Holes and slots ISO5836 ISO9269 Mechanical requirements ISO9585 ISO9585 Driving tools Keys and screwdrivers Drill bits, taps, countersink cutters ISO9714-1 In preparationBS3531-5.4:1993 BSI 08-1999 9 Annex B Bibliography: Inter
44、national Standards referred to in table of Annex A (This annex does not form an integral part of the Standard.) ISO5835:, Implants for surgery Metal bone screws with hexagonal drive connection Spherical under-surface of head and asymmetrical thread Dimensions 2) . ISO5836:, Implants for surgery Meta
45、l bone plates Holes corresponding to screws with asymmetrical thread and spherical under-surface 3) . ISO6475:, Implants for surgery Metal bone screws with asymmetrical thread and spherical under-surface Mechanical requirements and test methods 4) . ISO8319-1:1986, Orthopaedic instruments Drive conn
46、ections Part1: Keys for use with screws with hexagon socket heads. ISO8319-2:1986, Orthopaedic instruments Drive connections Part2: Screwdrivers for single slot head screws, screws with cruciate slot and cross-recessed head screws. ISO9268:, Implants for surgery Metal bone screws with conical under-
47、surface of head Dimensions 3) . ISO9269:1988, Implants for surgery Metal bone plates Holes and slots corresponding to screws with conical under-surface. ISO9585:, Implants for surgery Method for testing bending strength and stiffness of bone plates 3) . ISO9714-1:, Orthopaedic instruments Drilling i
48、nstruments Part1: Drill bits, taps and countersink cutters 3) . 2) Will cancel and replace ISO5835-1 at next revision stage. (ISO5835-1 cancelled and replaced ISO5835-1:1978 and ISO5835-2:1978.) 3) To be published. 4) Will cancel and replace ISO6475-1:1980 and ISO6475-2:1980.10 blankBS3531-5.4:1993
49、BSI 08-1999 List of references See national foreword.BS3531-5.4: 1993 ISO9268:1988 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for preparing BritishStandards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions BritishStandards are updated by amendment or revision. Users of BritishStandards should
