Otto Bock - Closure system

Users & Patients

Prostheses

Leg Prosthetics

Socket Technologies

Closure system

In addition to the right liner material, an optimum prosthetic fitting also requires the correct closure system. We offer the following closure systems depending on the mobility grade.

back to: Visit by Federal Chancellor Dr. Angela Merkel

The Münster supracondylar bedding from Otto Bock.

Münster supracondylar bedding and PTB

The Münster supracondylar bedding and PTB (patella tendon bearing) closure systems usually consist of a prosthesis with soft inner padding. A Derma Seal sock or conventional wool sock is pulled over the residual limb. The residual limb is protected by the soft, integrated padding (Soft Socket).

PIN fittings and shuttle lock

PIN fittings combine a liner with a so-called pin. This engages in a special shuttle lock and is securely anchored in the socket. A special unlocking pin makes the system easy to release.

Some of our closure systems use modern vacuum technology. It removes excess air between the liner and socket, keeping the prosthesis securely in place. Two versions are available: The vacuum can either be created using a passive valve or an active pump (Harmony® system).

Passive valve systems

Passive valve systems usually consist of a soft liner, an exhaust valve and a sealing sleeve. Excess air is expelled through the valve with the help of body weight, and is unable to stream back in.

Active negative-pressure systems

Active negative-pressure systems such as the Harmony® system use a pump that extracts most of the air between the liner and socket. This increases socket adhesion by a factor of four to five. While the shear forces (lifting forces) are relatively high with a passive closure system, the Harmony® system reduces these forces to a minimum.

For the best possible fitting results, we recommend the following liner / closure system combinations:

Material	Characteristics	Indications	Ideally used with
Silicone	Very durable Easy to clean	Residual limbs with good soft tissue coverage Low to moderate activity level Used with a specific weight bearing socket	Shuttle lock
Polyurethane	Yielding effect of the material ensures even pressure distribution	All residual limb types; especially sensitive, bony and/ or scarred residual limbs Low to high activity level Used with full-contact socket according to the Harmony® principle	Valve or Harmony® system
Copolymer	User-friendly and prosthetist-friendly Offers good protection against socket forces	Many residual limb types; especially residual limbs with dry skin Low to moderate activity level Used with a full-contact socket	Valve

Please note that the specified combinations of liner materials and closure systems constitute general recommendations. Actual fittings are always customised to you and your needs. Please consult your prosthetist if you are interested in Socket Technologies.