OEMs say they usually evaluate a contract partner on three factors: quality of work, delivery time, and cost. Small and new companies add a fourth qualification. “Can we get their attention and keep it?” says Dave Stoen, vice president of operations at Incisive Surgical Inc., a small medical-design firm.

Small companies obviously don't have big names but their products are just as important as any pacemaker. They want to be taken seriously. “We need production partners that engage early enough to optimize designs for high quality and low cost,” says Stoen.

For their part, contract product developers deliver more than attention. “A contract development firm can steer an OEM away from covering old ground and immediately establish new parameters to minimize costs and risks,” says Medical Division Manager Robert Andrews at Foster-Miller Inc.

Andrews suggests kicking off most projects with OEMs by first developing a requirements spec as a foundation for product development. “When the client already has specs and requirements, then we review them and occasionally suggest changes,” says Andrews. “When they don't have a complete specification, we might conduct market research to find key features that would go into the product. Without a requirement spec, the product development firm is shooting at a moving target.” Several examples show how outsourced partners have responded to design challenges from small and large companies alike.

Absorbable sutures

Take Stoen's firm, Incisive Surgical Inc., for example. The Plymouth, Minnesota company, (incisivesurgical.com), recently developed the Insorb Subcuticular Skin Stapler, a way to close surgical openings that combines the cosmetics of absorbable sutures with short closure times of metal skin staplers. Contract manufacturer UFE, Minneapolis, (ufe.com) evaluated and recommended modifications to the stapler's ten plastic components to improve moldability, assembly, and operation in the surgical suite. The absorbable staple is made of a copolymer (polylactic and polyglycolic acids) which is absorbed in a few months. The stapler is a sterile, single-patient use device loaded with 20 staples, enough to close an 18-cm incision.

While the absorbable staple was key, it could only become salable with the development of a mechanical stapler. Getting and keeping the attention of a contract manufacturer was high on Incisive Surgical's list because it is a small firm without previous products.

What's more, Incisive Surgical's engineering team had limited knowledge in injection-molded-part production, and flawless product performance would be imperative for commercial success. Stoen credits UFE with adding key process elements to the original design that created a product that has exceeded quality and cost objectives.

One-hand biopsy tool

Expertise in medical-product design, materials, and mechanism development let a contract engineering firm help C.R. Bard Inc., Murray Hill, N.J. (crbard.com) roll out an ergonomic biopsy tool that surgeons can operate with one hand. The joint team, Bard and product design and development firm Foster-Miller Inc., Waltham, Mass., also designed the product to meet requirements of the existing 510(k), helping Bard gain quick industry acceptance.

One-hand operation was essential. Previous design required that surgeons operate the device with two hands. Successful implementation came from several disciplines such as mechanism design, ergonomics, and human behavior to design a hand-held diagnostic device able to perform biopsies. The result is a simple design with all mechanisms in the handle. Consequently, the handle required a solid housing of a rigid material but also a flexible grip made of a resilient material. Elastomers and rigid polymers were selected to accommodate a design that could be injection molded.

Other design features are its low-force operability and ergonomic design. It also has a lockout function that promotes easy handling. The product can be cocked or triggered by the surgeon from either the top or side of the tool with one hand. A safety latch built into the handle makes the tool safe and reliable in use.

Almost foolproof urine tester

A durable point-of-care, urine-analysis device has an intuitive motion-control system that makes it simpler to use than a previous model. The unit, the Clinitek Status analyzer from the Diagnostics Division of Bayer HealthCare, reads urine strips. Its immunoassay cassettes withstand harsh use, even accidental abuse. The device analyzes urine samples on strips in a way that eliminates errors arising from human visual judgments. A touch-screen user interface makes it simple to use, and a motorized drawer accepts reagent strips or cassettes and positions them under optical analysis sensors. The drawer was the engineering focus of contract manufacturer Cambridge Consultants, in the U.K. and Boston, (www.cambridgeconsultants.com).

The previous sample drawer worked well under normal conditions when operators were familiar with the instrument. Prototype testing however highlighted a possible problem with untrained users - they might use too much force to close the drawer, thereby damaging the motor's gear teeth. “Other issues were how fast the contract manufacturer could design the modification, and that it fit current production tools and processes,” says Trevor Allison, R&D Director at Bayer Diagnostics' product development and manufacturing facility in the UK.

Early redesigns called for a sturdier motorized drawer than had been used in previous instruments. “The motorized table had to withstand the rigors of daily use by several operators using different reagents,” says Allison. Previous systems used a simpler mechanism that only transported one type of reagent. Allison says Cambridge Consultants worked in parallel with his team to provide the answer within a matter of weeks, keeping the product launch on schedule.

The design solution involved a heavier-duty motor and gearbox than had been used in previous systems. The gearbox was relocated so the force on the drawer can not damage it. The effort was combined with recommendations to assist the Bayer team in the design of an improved control and drive strategy, which involved sensing the drawer's insertion by feedback from motor windings, and driving the motor with a motion profile that improves both gear engagement and the final positioning of the reagent under the equipment's optics.

The sample drawer and the mouth of the enclosure also makes inserting the table more intuitive with guide ways and a visual indication of the right orientation. Better yet, these mechanical changes were made with modifications to existing molding tools. This avoided the time and cost involved with producing completely new tools.

How to cut production costs 25%

Conducting manufacturing assessments early in development and process verification let a design team at Accellent Inc., Wilmington, Mass. (accellent.com) reduce product cost 25% for a point-of-collection, blood system. What's more, the company saved $500,000 in the first year's production alone. The customer recouped engineering fees in just two months.

The OEM also wanted design changes that would not impact 510(k), tooling decisions, or launch date. The complex project had multiple components and a production process to match.

The contract manufacturer approached the project using DFMA (design for manufacture and assembly), bringing in materials, process and design experts to assist in the design plan. The contract manufacturer also conducted a six-week assessment to make best use of design and manufacturing synergies.