Postmarketing Study to Determine Performance of the SIGMA HP® PARTIAL KNEE SYSTEM
Postmarketing Study to Determine Performance of the SIGMA HP® PARTIAL KNEE SYSTEM
This is a postmarketing study to assess the overall performance and survivorship of the SIGMA
 HP® PARTIAL KNEE SYSTEM.
The purpose of this study is to collect more information about the Sigma HP® Partial Knee
 System made by DePuy International. The aim of this study is to measure how this particular
 type of knee replacement performs over a two year period.
Inclusion Criteria:

 -  Male or female subjects, aged at least 21 years.

 -  Subjects who are able to give voluntary, written informed consent to participate in
 this clinical investigation and from whom consent has been obtained.

 -  Subjects, who, in the opinion of the Clinical Investigator, are able to understand
 this clinical investigation, co-operate with the investigational procedures and are
 willing to return to the hospital for all the required post-operative follow-ups.

 -  Subject has non-inflammatory degenerative joint disease (NIDJD), including:
 osteoarthritis, posttraumatic arthritis, avascular necrosis and chondrocalcinosis.

 -  Subject has a functional stable knee.

 -  Subject, in the opinion of the Investigator, is suitable for either a single or
 bicompartmental knee replacement.

 -  Subject meets the following selected radiographic parameters:

 -  X-ray evaluation confirms the presence of NIDJD

 -  Disease location: 1 to 2 compartments, maximum. Disease can be present in the
 patellofemoral compartment, the medial tibiofemoral compartment, lateral
 tibiofemoral compartments alone or in any two compartments.

 -  Disease severity: Kellgren and Lawrence44 Grade II or greater for all
 compartments replaced.

 Exclusion Criteria:

 -  Subjects who, in the opinion of the Clinical Investigator, have an existing condition
 that would compromise their participation and follow-up in this clinical
 investigation.

 -  Women who are pregnant.

 -  Subjects who are known drug or alcohol abusers or with psychological disorders that
 could affect follow-up care or treatment outcomes.

 -  Subjects who have participated in a clinical investigation with an investigational
 product in the last 3 months.

 -  Subjects who are currently involved in any injury litigation claims.

 -  Multiple joint involvement that will compromise rehabilitation (for example: advanced
 hip, ankle or spine disease).

 -  Known to be a prisoner, mentally incompetent, an alcohol / drug abuser, involved in
 medical-legal case or worker's compensation

 -  Previous knee arthroplasty (any type) in any one of the three compartments of the
 knee.

 -  Requires more than a lateral soft tissue release or an anterior cruciate ligament
 reconstruction.

 -  Uncorrectable anatomical tibio-femoral angle.

 -  Bone deficiency requiring structural bone grafts to support the implants.

 -  Previous patellectomy.

 -  For Subjects indicated for a patellofemoral arthroplasty, Subject has uncorrected
 patella baja (Caton-Deschamps ratio less than or equal to 0.6).

 -  Tri-compartmental disease process (patella-femoral, medial tibio-femoral and lateral
 tibio-femoral).

 -  Active bacterial infection that may spread to other areas of the body (e.g.,
 osteomyelitis, pyogenic infection of knee joint, urinary tract infection, etc.).

 -  Significant neurological or musculoskeletal deformity or a disease that may affect
 gait or weight bearing, (e.g., muscular dystrophy, multiple sclerosis, amputation).

 -  Known allergy to implant materials.