Hardware removal is always ’more difficult than expected,’ especially in children
William T. Obremskey, MD, reports that complication rates remain high.
The indications for hardware removal have often seemed somewhat subjective. There are those obvious cases where it presents mechanical symptoms or removal is necessary for another procedure to be done. In addition, surgeons often underestimate the time necessary for the removal and the patients return to normal activities. I have asked Dr. William T. Obremskey to share with us some insight into the current indications and potential problems with hardware removal.
Douglas W. Jackson, MD: Some orthopedists remove most of the hardware in younger patients. What are the common indications for removing hardware in the pediatric population?
William T. Obremskey, MD, MPH: The data on hardware removal in the pediatric population are not clear. Drs. Bob Esther and Matt Busam helped me put together information for a recent publication in Journal of the American Academy of Orthopaedic Surgeons about hardware removal. Textbooks have varied from Chapmans textbook, which recommends that in children we advise routine removal of implants. And in Skeletal Trauma, editors Drs. Green and Swiotkowski do not recommend routine removal of implants, except where Dr. Rout states that plate removal from the femur is advocated for almost all children.
COURTESY: WILLIAM T. OBREMSKEY |
The trend in children seems to be to leave more implants, where previously hardware removal was routine. An example is in slipped capital femoral epiphysis injuries, where screw removal is no longer routinely performed. Hardware for proximal femoral reconstructive osteotomies are more commonly removed due to the large nature of the implants and the potential for future surgical intervention in this patient population. These large, bulky implants cause a significant stress riser and are difficult to remove once they are encased in callus or bone. (Figure) In the pediatric population, flexible intramedullary nails that are used in trauma are commonly removed. A recent review of the use of flexible nails in pediatric femur fractures, though, did not routinely recommend hardware removal.
Jackson: What are some of the criteria that should be considered before removing hardware used for fracture fixation?
Obremskey: Indications for hardware removal after fracture fixation can include hardware failure with bony instability or painful nonunions, chronic infections and mechanical pain. Patients that have mechanical pain due to hardware prominence around joints or areas without much soft tissue coverage are reliably relieved with hardware removal, but deep, chronic, aching pain is much less reliably relieved. I tell patients that this deep, aching pain is relieved in 50% of patients. Some feel they may have a metal allergy and desire hardware removal. Dr. Mark Swiotkowski taught me years ago that some patients with dull, achy pain are good candidates for hardware removal due to a potential nickel allergy. These patients tend to be fair-skinned, red-haired women who have a history of multiple drug allergies and irritation from costume jewelry or jewelry that is not pure gold. This anecdotal experience has seemed to have held up fairly well, and these patients often report immediate pain relief upon their first postoperative visit.
Hardware removal for fixation across joints is more controversial. Historically, syndesmosis screws and screws across midfoot joints were often removed. There are certainly case series of these implants being left in place with no known ill effects. Fixation across pelvic joints in young women, such as the pubis or sacroiliac joints, may need to be routinely removed if the women desire to become pregnant and deliver vaginally.
Adult patient or physician concerns that may not be appropriate for hardware removal include risk of future fractures due to stress risers, increased risk of cancer and concerns for metal detection in frequent travelers. Patients have been able to return to impact and contact sports with implants in place without complications. Large epidemiologic studies have shown no increased risk of cancer in patients with retained implants, and metal detection for travelers is easily substantiated with hand-held screening devices.
Jackson: What are some considerations following hardware removal to decrease possible refracture through a cortical screw hole?
Obremskey: A single screw hole can decrease the compressive load of cancellus bone 20% or the torsional stability of a diaphyseal bone 50%. Patients need to be aware of these risks and avoid impact or torsional activity until bone strength has returned. A dog model of a single screw hole showed torsional strength returns in approximately four weeks. But radiographic findings in adults show it does not return to near normal until 18 weeks. The data on return of normal strength in humans after hardware removal is not known, but protecting long bones after hardware removal for two to three months is reasonable.
Jackson: Occasionally, hardware removal may be more difficult than expected. What are some points to cover with patients regarding potential complications, cost and return to work estimates?
Obremskey: Hardware removal is always more difficult than expected. The old adage that you can never look good with hardware removal still is true today. Reports of hardware removal with intramedullary nails and ankle fractures indicate that the greatest risk for hardware removal is lack of complete pain relief. Complications have been related to the size of implants removed in forearm fractures, and in inexperienced surgeons performing hardware removal. Common complications include wound infection, nerve injury and refracture.
Due to the relatively high complication rates associated with routine hardware removal, most surgeons do not recommend it in the adult patient population after a fracture or reconstructive procedure, unless the hardware is symptomatic, the patient has significant pain or the patient has a nonunion or infection. Unnecessary costs cannot be ignored, and an approximate cost of outpatient implant removal with 30 minutes to one hour of operative time is approximately $4000 to $8000. The indirect costs are also significant, such as lost time to work, and would depend greatly upon implant location and type.
References:
- Brooks DB, Burstein AH, Frankel VH. The biomechanics of torsional fractures. J Bone Joint Surg Am. 1970;52:507-514.
- Chapman MW: Principles of Internal and External Fixation. In: Chapman MW, ed. Chapmans Orthopaedic Surgery. 3rd ed. Philadelphia, PA: Lippincott Williams and Wilkins; 2001: 375-376.
- De Souza L, Gustillo RB, Meyer TJ. Results of operative treatment of displaced external rotation-abduction fractures of the ankle. J Bone Joint Surg Am. 1985;67:1066-1073.
- Green NE, Swiontkowski MF. Skeletal Trauma in Children. 3rd ed. Philadelphia, PA: Saunders; 2003:424.
- Juliano PJ, Yu JR, Schneider DJ, Jacobs CR. Evaluation of fracture predilection in the calcaneus after external fixator pin removal. J Orthop Trauma. 1997;11:430-434.
- Luhmann SJ, Schootman M, Schoenecker PL, Dobbs MB, Gordon JE. complications of titanium elastic nails for pediatric femoral shaft fractures. J Pediatr Orthop. 2003;23:443-447.