Zimmer® M/L Taper Hip Prosthesis with Kinectiv™ Technology

Hip designed to fit the unique anatomies of men and women

Superior intraoperative flexibility to optimally restore  hip joint kinematics

Restoring leg length, joint stability, and range of motion involve distinct surgical challenges. The Zimmer M/L Taper Hip Prosthesis with Kinectiv Technology introduces a system of modular stem and neck components designed to help the surgeon restore the hip joint center intraoperatively by addressing leg length, offset, and version independently. The resulting array of neck options efficiently targets a broad range of male and female patient anatomies.

M/L Taper Hip Prosthesis with Kinectiv Technology

Clinical Advantages

Clinical Benefits

  • Independent leg length and offset adjustability to optimize hip joint kinematics and function.
  • Independent version adjustability to optimize head center position without affecting proximal stem fit, leg length or offset.
  • Reduced neck geometry and anteverted / retroverted neck options for efficient impingement resolution and enhanced range of motion which helps to mitigate the risks of accelerated implant wear and dislocation.
  • Broad range of head centers better match the wide range of patient anatomies among men and women and help avoid low, bone sacrificing neck cuts.
  • Broad range of head centers provide more opportunities to optimally restore fit and function in the limited view environment encountered in minimally invasive hip procedures.
  • Low profile implant eases stem insertion and minimizes soft tissue trauma.

Independent Control

Proper offset and leg length restoration improve total hip replacement function and minimize the risk of dislocation and limp.1,2 For traditional hip systems, leg length and offset are coupled and surgeons are often forced to accept the coincidental change in leg length or offset when making changes intraoperatively (i.e. when simply changing the head). The Zimmer M/L Taper Hip Prosthesis with Kinectiv Technology allows surgeons to independently adjust leg length and offset intraoperatively after stem implantation to optimize each dimensional factor without affecting the other.

The Zimmer M/L Taper Hip with Kinectiv Technology also allows independent version adjustments after stem implantation. This facilitates optimal stem position based on the patient’s proximal femoral anatomy while restoring head center position.

The 3D Grid

M/L Taper with Kinectiv Technology

Independence

  • Independent leg length and offset adjustability following stem implantation.
  • Leg length discrepancy is a leading source of patient dissatisfaction in total hip replacement 3-6

Version by Design

  • Independent version adjustability following stem implantation.
  • Progressively increasing version with decreasing offset to better match patient anatomy.
  • Intraoperative range of motion adjustment to resolve impingement and mitigate risk of accelerated implant wear and dislocation.

Intraoperative Flexibility

  • No need for surgeon to adjust stem fit to achieve version.
  • Version options to optimize stem fit and head center location.
M/L Taper with Kinectiv Technology M/L Taper with Kinectiv Technology M/L Taper with Kinectiv Technology
Stem: non-modular, straight neck
Disadvantage: cannot adjust for version following stem implantation 		Stem: modular, straight neck Stem: modular,
anteverted neck
Advantage: optimized version following stem implantation

Range of Motion 

Impingement of the femoral and acetabular components has been shown to increase risk of dislocation and accelerate wear of the liner.8,9 Since Kinectiv Technology uses +0 heads only, the geometry of each neck component can be specifically optimized for strength and range of motion based on the +0 head length. Kinectiv Technology also eliminates the use of skirted femoral heads that are necessary for the longer offset options of other designs. In addition, the ante/retroverted necks allow the surgeon to adjust version intraoperatively after cup and stem implantation and further fine tune the range of motion for the patient.  

Reduced Neck Geometry

  • Each neck can be optimized for use with +0 head
  • Reduced neck geometry enhances range of motion

Anteverted and Retroverted Necks

  • When cup placement is not optimal, version options can relieve impingement
  • Version options provide opportunity for surgeon to intraoperatively tune the range of motion to avoid dislocation.
  • Dislocation is the second most prevalent complication in total hip replacement with a 2-4% incidence 10-12
  • Dislocation is a significant financial burden to health care system.13

Related Articles

Zimmer Gender Solutions Technology
Zimmer Minimally Invasive Solutions Procedures
M/L Taper with Kinectiv Technology - Built on Proven Implant Philosophy
Design Considerations

References

  1. Iorio R, Healy W,L Warren PD, Appleby D. Lateral trochanteric pain following primary total hip arthroplasty, The Journal of Arthroplasty 2006;21:233-236.
  2. Bourne RB and Rorabeck CH. Soft tissue balancing the hip. Journal of Arthroplasty. 2002;17(Suppl 1):17-22.
  3. Konveys A and Bannister GC. The importance of leg length discrepancy after total hip arthroplasty. The Journal of Bone and Joint Surgery Br. 2005;87-B:155-157.
  4. Hoffmann AA and Skrzynski MC. Leg length inequality and nerve palsy in total hip arthroplasty: A lawyer awaits! Orthopaedics 2000;9:943-944.
  5. White AB. AAOS Committee on professional liability: Study of 119 closed malpractice claims involving hip replacement. AAOS Bulletin July 1994.
  6. Bal BS, Managing litigation risk in minimally invasive total joint surgery. AAOS Bulletin. April 2006.
  7. Shon WY, Baldini T, Peterson MG, Wright TM, Salvati EA. Impingement in total hip arthroplasty: A study of retrieved acetabular components. 2005;20:427-435.
  8. Biedermann R, Tonin A, Krismer M, Rachbauer F, Eibl G, Stöckl B. Reducing the risk of dislocation after total hip arthroplasty. The effect of orientation of the acetabular component. The Journal of Bone and Joint Surgery Br. 2005;87B:762-769.
  9. D’Lima DD, Urquhart AG, Buehler KO, Walker RH, Colwell CW. The effect of the orientation of the acetabular and femoral components on the range of motion of the hip at different head-neck ratios. The Journal of Bone and Joint Surgery Am. 2000;82-A:315-321.
  10. Philips et.al. Incidence rates of dislocation, pulmonary embolism and deep infection during the first six months after elective total hip surgery. J Bone Joint Surg. Am. 2003; 85:20-26.
  11. Morrey BF. Instability after total hip arthroplasty. Orthopedic Clinics of North America. 1992;23:237-248.
  12. Morrey BF. Difficult complications after hip joint replacement. Dislocation. Clinical Orthopaedics and Related Research. 1997;344:179-187.
  13. Sanchex-Sotelo J, Haidukewych GJ, Boberg CJ. Hospital cost of dislocation after primary total hip arthroplasty.  The Journal of Bone and Joint Surgery AM. 2006;88-A:290-294.