Surgical Instrument Repair – Art or Science?

by Anne Reed, BS, and Beverly Dysert

This article:

Instrument patterns abound. There are many manufacturers, many makes and models, and many parts for many purposes. Quality may vary, but for the Old-World instrument maker it was a labor of love; it was a unique blend of craftsmanship and engineering to render a product of pride. Though streamlined by the industrial revolution, the same respect for the process exists in the finest manufacturing plants today.

That same confidence must come from those chosen to care for instruments today-an artisan in his feel and touch, a scientist in his skill and knowledge. Only a repair specialist like this can deliver an instrument to the surgeon’s hands with the same form and function engineered by the original maker.

That is why it is significant to recognize differences in repair organizations and the standard of care they instill in their technicians. Do they produce artists, machinists, or a blend of both? While an instrument can be mechanically restored to action, a real craftsman understands instrument behavior and ensures this element survives during the repair process as well.

The goal, of course, is to bring each instrument back to its original performance level. To this end, a technician must have studied instrument specifications. He must understand the relationship between the instrument and the nature of matter it impacts in the patient (i.e., bone, muscle, soft tissue, suture, etc.). He must bear an intrinsic knowledge of the action expectations of the surgeon in wielding the instrument-angle, approach, friction, bend, lift, force, torque, resistance, etc. His materials and parts must be the finest OEM-style quality. And, he must be committed philosophically to the role his efforts play in helping deliver the finest in patient care. Intuitive instrument managers will always look for this integrity of purpose from their instrument repair source, but to differentiate, one must be nearly as insightful about instruments and their care and maintenance as the repair technician.

The American Iron and Steel Institute (AISI) has identified various formulations of steel and has cataloged them, so that AISI Series 300 and 400 stainless steels are used for surgical instruments. Other common elements are titanium and sterling silver. Chrome plated materials are virtually obsolete due to the increased use of ultrasonic cleaners in reprocessing. No matter what the metal, the repair demands a unique approach, and not all technicians are skilled enough to effect repairs on all types.

To further categorize, there are three types of finishes on stainless steel instruments, and a good technician will leave the same finish on instruments after he repairs them. The highly polished finish reflects light and can cause glare that may distort the surgeon’s vision. A satin or dull finish does not reflect light and helps eliminate glare. The solid ebony finish also eliminates glare and is suitable for laser surgery because it is critical that the laser not be accidentally reflected.

Buying the highest quality instruments provides a degree of protection from the inconvenient and rapid breakdown of inferior products, but inevitably, all instruments will at some point need maintenance and/or repair. Preventing serious damage not only saves money but also helps ensure that instruments will remain in service for their maximum life expectancy. Consequently, it is important to be vigilant about potential problems, so they can be averted whenever possible.

Inspect an instrument with the eye of a repair craftsman. Knowing what to look for will not only help preserve equipment, it will reveal much about the skill, training, and conscientiousness of the person charged with repair responsibilities for the facility.

Warning Signs

While many problems are unique to certain patterns, some indicators of potential instrument failure are common to most surgical instruments. Always look for corrosion, pitting, or cracks on the instrument’s surface because cracks are a sign that breakage is imminent. Metal stress is fatigue of the material and too much stress can result in breakage. Joint movement, jaw alignment, and ratchet function should be checked on all hinged instruments. Joints should work smoothly, jaws should be perfectly aligned and should not overlap, and ratchets should close easily and hold securely. Cutting instruments with dull, nicked, or dented edges can cause trauma to tissue. They should be inspected for nicks, burrs, cracked inserts, and broken tips. Certain instruments demand examination for problems inherent in their particular design.

General scissors:
Check for cracks on both sides of the screw area and along the blades, especially if carbide inserts are installed. Check for cracked carbide, or carbide cracked away from the main body of the scissor, and for cracked ring handles. Look for any weakness or wear in the screw area. Stripped screws can be replaced, and stripped inner threads of the scissor can be repaired. Always check for corrosion, pitting, and metal stress. Evaluating the condition of the blades is vital to the repair of scissors. If they have been ground down too far or shortened in any way, the scissors may be beyond repair. The judgment call would be if they could be repaired to original condition and still have 30% life or better.

General forcep style box lock instruments:
Look for cracks in the lock and finger rings and for cracked, extremely bowed or metal stressed jaws. Check for severely worn or broken teeth of ratchet locks. Extreme pitting and excessive wear or debris in the box area can also jeopardize instrument life span. All instruments must run smoothly without any wobble or drag. Make sure the handles are straight and ratchets lock and align properly. The jaws should be aligned so the teeth mesh together with no side kicking or overlapping. Forcep tips must meet and close completely without sticking. Hold the instrument up to the light to make sure all jaws and teeth close properly. There should be no light showing between the jaws.

Hand-held self-retaining retractors:
Check for cracks around the center screw, ratchet pin, at the base of the ratchet side, and the ratchet. Check for misaligned ratchet arms, and check the tips for alignment or dullness. It is important that the retracting fingers mesh without rubbing when they are fully opened. Examine the spring for burrs or any damage that might make the thumb ratchet hang up. The spring should fit tightly on the main frame, the total length of the spring. The spring should be long enough to reach the ratchet end and short enough not to hit the ratchet slide when the thumb ratchet is pressed or depressed. If the thumb ratchet is not closing properly, check the angle on the spring end of the ratchet. It should be approximately 45°. If necessary, the angle can be reappointed or changed.

Kerrison punches:
Check for cracked or broken springs. Make sure the cutting edge is fitting up to the fixed shoe. The cutting edge has to fit this shoe for the punch to cut evenly. Every time these instruments are sharpened, they lose a little life on the top slide. It is important to recognize when the kerrison is becoming “out of throw,” which means the cutting edge does not exert enough pressure on the stationary shoe to cut efficiently.

Osteotomes and chisels:
Osteotomes and chisels are designed so only about 3/4″ is hardened steel. The rest of the shaft is softer, but every time they are sharpened, they lose some of that tempered length. A talented repair professional knows the lengths, sizes, and cuts of all the various patterns, so he understands that to sharpen beyond the hardened steel is to compromise the instrument so it will fail during use. Severe nicks on the cutting edge can be removed but only by an experienced technician. Bent or twisted osteotomes can often be aligned but only if it will not cause severe metal stress. While durable, osteotomes and chisels still take more abuse than any other instrument, so they must continue to withstand the impact that is constantly applied during surgery.

Needleholders:
There are many needleholder patterns in use, and some require a more extensive inspection. But no matter what style, all evaluations should be performed under a microscope as some damage cannot be seen by the naked eye. Tungsten carbide inserts look like a row of pyramids, but after extended use, the points or tips of these pyramids wear down so that they will no longer grip the needle effectively. When this occurs, the inserts should be replaced. It is important to know, however, that there are many sizes and patterns of inserts, and if an inappropriate insert is placed in the jaws, it will compromise the effectiveness of the needleholder. Since not every technician carries all the patterns, this is a frequent abuse. Different needleholders accommodate different needles, and only an accomplished professional knows and understands these differences. Additionally, it is critical that the repair person has an awareness of appropriate temperature and solder use to ensure absolute adhesion for long lasting results.

While proper insert replacement can repeatedly breathe new life into a needleholder, there does come a time when it can no longer endure the heat and stress of the repair process and should be replaced. A trusted repair specialist will advise when this measure becomes necessary. To self-determine, however, simply inspect the side of the jaws. If the metal in the jaws is thinner than the carbide insert, or if the jaw can be moved sideways with one’s thumb, then it should be tagged as “non-repairable.” Other indicators include warps or cracks in the lower jaws, the box lock, and the outer and inner tops of the handles. Look for broken or cracked ratchets, severe corrosion in the metal, and most importantly, fault lines indicating metal stress on any surface of the instrument. Screws and springs should also be checked for cracks and stress.

Small needleholders such as websters, micros, ryders, needleholder/scissor combinations, and TC forceps require a more extensive inspection in addition to steps of the basic evaluation. TC forceps are inspected first at the lower handle for cracks, for metal stress (insert, jaw size, and softness), and any type of fault or corrosion near the upper part of the instrument. The blades of the needleholder/scissor combinations should be examined carefully to ensure they have not been ground down so far that they will no longer cut evenly. Metal stress is the major factor in the inspection of webster and ryder needleholders because of their size and delicacy. Bent jaws commonly render them non-repairable. Micro needleholders require a check of the locking springs for cracks, metal stress, and stripped screws.

Hemostatic clip appliers:
Inspecting these instruments involves looking for cracked box locks, broken springs, and spring catches. Also, check for proper jaw alignment. A capable surgical instrument repair specialist keeps clips of all four sizes available for testing alignment. One must be able to fit the clip applier jaws over the clip smoothly in the cartridge and then extract the clip without any pressure to the handles. The clip must then remain in the applier jaws. At this point, close the handles. The clip should close flat from top to bottom.

Single action bone cutters:
Check the instrument for cracks and stress in the box locks, jaw base, and springs. Loose box locks are common in single action instruments and must be tightened; otherwise, the misaligned jaw will “side bite,” which means taking off more bone than necessary. Check the “throw” (as mentioned in the kerrison punch section). Make sure that as the blades close, the tips close first. This instrument should not be sharpened razor sharp. It is very important that it cuts from the very tip to 3/4″ of the way down the blade. Also, make sure there is not a burr build-up on the cutting edge as this will affect the cut of the instrument.

Pituitarys:
Check the jaws for cracks around the pins and inside the jaws. Make sure the jaw pins are snug. If either pin is loose, it will need to be replaced. To check which pin is worn or bent, place fingers on the jaws closed and move the handle. Check the “throw” points in the back of the jaw and inside the handles.

Endo/lap instruments:
Disassembly of MIS instruments is vital for proper repair. All parts must be microscopically checked for cracks in the jaw housing, pin joints, blades, jaws, linkage, etc. Some repair vendors are known to solder an inner shaft together, replace it, and charge for a new shaft. An inner shaft of an endoscopic or laparoscopic instrument should never be soldered at any point. The inner mechanism works the entire unit and is connected from the handles down to the jaw housing. These already defective, resoldered parts weaken and increase the risk of breakage during surgery. Beware of vendors who use parts that are not the proper grade of stainless steel because this will cause rust after a few uses. The parts must be manufactured from 300 to 400 series steels, which is non-magnetic and corrosion resistant. Always avoid technicians who involve used or cannibalized parts and those who do not disassemble the instruments or only repair visible damage.

Endoscopic/laparoscopic instruments:
Costly instruments require expensive medical-grade parts to repair, and these, along with the necessary training, are not available from all instrument repair vendors. Since these instruments represent a substantial investment, it is important that only competent technicians be allowed to work on them. For quality repair, insist that the instrument be disassembled and ultrasonically cleaned, only brand new replacement parts be installed, that only lead and cadmium-free solder be used. Many companies use the more inexpensive lead-based or silver solder, but it discolors and weakens the instrument because it must be applied at such high temperatures. Forever after, this instrument is subject to premature breakage. A good repair vendor can rebuild damaged endo/lap units such as working elements, deflecting bridges, resectoscope sheaths, etc.

Proper Care and Handling

If properly cared for, the average life expectancy of an instrument is approximately 10 years. Proper sterilization of instruments during and after surgery can help prevent malfunctions and deterioration. Always read and follow the manufacturer guidelines for each individual instrument when purchased. They should be adhered to at all times. There are different procedures for different instruments.

Check with the manufacturer of the individual instrument to determine its material content. Be sure that the solutions used are compatible with the metal so that no further damage occurs. Corrosion of an instrument is a slow disintegration usually caused by a destructive agent. It can also be caused by excessive moisture on instruments in sterile packs, excessive moisture inside the sterilizer, or mineral deposits on the chamber of the sterilizer being transferred to instruments during sterilization. Pitting is caused by exposure to corrosive materials like saline solution and detergent residue or by mixing incompatible metals. Any one of these problems could damage an instrument permanently.

Any orange-brown stains are indicators of corrosion and potential rust. If the surface beneath the stain is pitted, remove the item from service before it is transfers the problem to other instruments.

Avoiding the Repair Mechanic

Maintaining instrument assets is burden enough without the distracting thought of placing them in the hands of someone who can damage them further. It is an awareness of the differences that will prevent any department managers from misplacing trust in those who claim expertise they do not possess.

A good technician tags stressed and severely damaged instruments “non-repairable” because they do not want them to fail in a critical surgical situation. But, it is still important to check those instruments because, while some repair providers have the expertise to repair extensive damage,others do not, so they will often tag them “non-repairable” simply because they personally cannot complete the repair or they do not carry the necessary parts. Worse, they attempt a repair that results in further damage that cannot only reduce the operational life of one’s equipment, it can also cause an instrument to fail during surgery.

Beware of repair vendors who fill cracks in an instrument with solder and claim a successful repair. The heat of the solder will only increase damage to an already weakened instrument and set it up for failure. Cracked instruments should be replaced. Beware of repair vendors who put tungsten carbide inserts in clearly stressed needleholder jaws. When the surgeon applies pressure to grip the needle, the jaws will bend, and so, again, these should have been replaced. Beware of repair vendors who continue to sharpen blades and jaws down to almost nothing, simply to complete the repair. Shortened blades do not deliver the proper action to the surgeon and should be removed from the tray.

Hiring a Repair Craftsman

A good technician does nothing to jeopardize the appearance or integrity of a surgical instrument. Insist on a repair vendor who has an extensive parts and materials inventory and provides a written warranty. Understand that when a reputable repair company advises replacement, it is because the structural integrity of the unit has been so compromised that it is no longer in the best interests of the patient or facility to use it.

A good technician has the capability to sharpen, realign, refurbish, reinsulate, refinish, resolder, replace pins/screws, pins, and other parts and can address repairs of obsolete instruments.

A good repair specialist can restore electrosurgical instruments to original condition by reinsulating barrels, handles, and shafts, using only medical grade materials that meet or exceed the manufacturers’ specifications. Furthermore, they use a foolproof means of testing for insulation degradation like InsulScan™, that does not risk doing further damage to the instrument surface.

Certainly, every insight into identifying a potential instrument problem is helpful to the process of managing an efficient operating room and central sterile supply department. But, when problems are recognized, the finer solution is to involve an instrument caretaker who approaches the job at hand with a scientific aptitude as well as a passion and eagerness for the more intangible results.

Unlike assembly line manufacturing, the repair person must relate with an instrument. State-of-the-art machinery and techniques are essential, but for a time, that technician becomes the surgeon. With the instrument in hand, he flexes and feels it, just as it is to be used on a patient. He senses instinctively how vital his work is in a critical care situation. He respects his job as an artisan, not just a mechanic. He wants a department manager who trusts him with those instruments to be proud of her choice and astonished at the results. This artistic conscience is rare and sometimes the repair results can be subtle, but a real instrument craftsman knows the difference and so does the surgeon. Now, enlightened managers can understand it, too.

Beverly Dysert is an Instrument Product Manager for Mobile Instrument Service and Repair (Bellefontaine, Ohio). Anne Reed is Vice President of Mobile Instrument Service and Repair.

References

1. Great Plains Society for Hospital Central Service Personnel Instrument Manual
2. Brooks-Tighe SM. Instrumentation for the Operating Room, A Photographic Manual.
3. Association for the Advancement of Medical Instrumentation, 1996 (ST33).
4. Mobile Instrument Service and Repair, Inc. Sharpening and Repair Procedure Guide.
5. AAMI Recommended Practices. Volume 1.1: Sterilization, Part 1, 1998 Edition.