This article is more than 5 years old. Information may no longer be current.
Under what circumstances should hardware be removed following pediatric distal femoral osteotomy?
Click Here to Manage Email Alerts
Click here to read the Cover Story, "Distal femoral osteotomy: Short-term deformity solution needs long-term follow-up."
On a patient-by-patient basis
Distal femoral extension osteotomies, often times combined with patellar tendon advancement, are often used for the treatment of persistent crouch gait in adolescents and young adults with CP. These osteotomies are typically stabilized with internal fixation devices, such as a blade or locking compression plate to maintain reduction, decrease immobilization and promote early weight-bearing.
While there are no reported outcome studies regarding elective implant removal after extension osteotomy, Stout and colleagues, in their review of 73 patients with CP undergoing surgical treatment for knee flexion contractures, reported that in the 49 patients who underwent distal femoral osteotomy using a 90° blade plate, there were no hardware-related complications and the plates were not removed. Rutz and colleagues showed of 38 patients undergoing 63 distal femoral extension osteotomies, there was one implant-related complication (locking screw loosening 6 weeks postoperatively). They routinely removed the plates in 94% of patients for unspecified reasons.
The decision to remove implants from children is controversial. The Pediatric Orthopaedic Society of North America Evidenced-based Medicine Committee reviewed the scientific evidence for elective removal of orthopedic implants in children. Due to the paucity of quality studies and lack of control groups, there was not enough evidence to make a formal recommendation. However, they estimated the overall complication rate from implant removal to be about 10%.
Implant removal after distal femoral extension osteotomy, like any other surgical decision, should be based on the risks and benefits to each patient. In asymptomatic patients, there is no indication for routine hardware removal due to the lack of proven benefit and the increased risk for surgical complications, especially in the CP population due to the high prevalence of comorbidities.
Concerns exist about pathologic fracture around a rigid metallic implant caused by osteopenic bone. While this is a possibility, this complication following distal femoral extension osteotomy has not been widely reported, which may be due to the fact distal femoral extension osteotomy is typically performed in ambulatory CP patients whose bone density may not be as compromised as in non-ambulator patients.
Although proponents of routine implant removal about the hip argue this helps facilitate eventual total hip arthroplasty, there is no role at this time for total knee arthroplasty in CP patients. The only indication for implant removal following distal femoral extension osteotomy is the rare patient with a symptomatic implant after the osteotomy has healed. This issue highlights the need for quality studies to address the risks and benefits of implant removal in pediatric orthopedic patients.
- References:
- Lee SY, et al. J Korean Med Sci. 2015;doi:10.3349/jkms.2015.30.4.489.
- Raney EM, et al. J Pediatr Orthop. 2008;doi:10.1097/BPO.0b013e3181875b60.
- Rutz E, et al. J Pediatr Orthop. 2012;doi:10.1097/BPO.0b013e31824b29d7.
- Stout JL, et al. J Bone Joint Surg Am. 2008;doi:10.2106/JBJS.G.00327.
Jeffrey R. Sawyer, MD, is professor of orthopedic surgery at University of Tennessee Campbell Clinic, in Memphis, Tenn.
Disclosure: Sawyer reports no relevant financial disclosures.
Hardware removal advised in growing child
Implant removal in children is a controversial topic. During training when I asked my mentors how they approach this issue, the answer was always opinion-based, as in “I always...” or “I never...” As a general approach, most pediatric orthopedic surgeons remove implants in growing children. This is especially true near the distal femur, which is the most powerful physis. As the femur elongates and grows in width, any retained implants will move in relationship to their original position. Most commonly this movement is toward the diaphysis of the bone. The consequences of having a buried implant in the diaphysis are increased risk for fracture and increased difficulty in removing the implants in the future. While the literature is not robust in its discussion of implants around the knee, we do have some evidence from Woodcock and colleagues that retained implants around the hip will complicate future surgeries, making them longer and requiring more complicated techniques. Thus, in a growing child, implant removal is probably the best advice.
However, femoral implants that are placed in a child who is skeletally mature or who has little growth remaining can be retained. Future removal, which can be a substantial portion of any future surgery, would not be as difficult because the implant would be just as accessible for retrieval as when it was placed. This falls in line with many practices in adults of leaving implants in place unless they are symptomatically painful.
In short, if the child has significant growth remaining, one should consider implant removal at the knee. However, if the child is skeletally mature, those same implants can be retained. These are guidelines, but not rules, such as “I never” believe that “I always” have the answers.
- Reference:
- Woodcock J, et al. J Pediatr Orthop. 2013;doi:10.1097/BPO.0b013e3182784e3e.
Todd A. Milbrandt, MD, MS, is a pediatric orthopedic surgeon at Mayo Clinic in Rochester, Minn.
Disclosure: Milbrandt reports no relevant financial disclosures.