Caution urged when using two-stage surgery for pediatric flexor tendon injuries

Although similar to adult procedure, two-stage technique has twice complication rate in children.

Issue: December 2006

Late presentation, demanding surgical techniques and various degrees of injury are just some of the challenges of pediatric flexor tendon injuries.

At the American Society for Surgery of the Hand annual meeting, Peter M. Waters, MD, an orthopedist at Boston's Children's Hospital, offered surgeons tips for treating these injuries. "The first [step] is assume that all glass lacerations in children are bad and really teach your emergency room [and] your primary care physicians to be aggressive about this, because if you miss them, it is a lot harder later," Waters said during his presentation. He also noted that home exercise equipment and jersey fingers — a disruption of the flexor digitorum profundus tendon — might also cause flexor tendon injuries.

Examine wounds

He suggested examining the wounds of young children and infants in the OR and semi-urgently repairing injuries in older patients. A literature review covering the past 50 years shows adequate results with primary repair for acute injuries.

"There's about 70% to 85% roughly total range of motion, [and] approximately 75% to 80% good to excellent results," Waters said. He also said that flexor pollicis longus (FPL) repairs have superior results for zone II injuries compared to flexor digitorum profundus (FDP) and flexor digitorum sublimis (FDS). While it remains unclear if surgeons should resect the FDS alone or repair it with the FDP, Waters said that he repairs both tendons, "unless they're severely ugly." He cautioned that if the FDP is removed, the surrounding area should remain intact.

For partial lacerations, MRI or ultrasound may help surgeons identify the degree of deformity. "If you're going to use them, you've got to have reverse photography and really good, reliable radiologist," Waters said. For lacerations less than 50%, he does not repair the tendons and prescribes early motion. To treat acute injuries, surgeons should choose sutures based on tendon size.

Complex injuries

In chronic FDP absent injuries, the role of tenodesis, amputation and arthrodesis is limited. "Tenolysis is appropriate in certain patients, but I have to say, 'I hate this operation,'" Waters said. "This is a hard operation and it is really hard in kids."

Most patients meet the criteria for single-stage grafting. "I do single-stage, free tendon grafts in older kids, appropriate to their level of commitment," Waters said. "I spend a lot of time talking with kids before I take them to the OR and make sure they understand, and I don't do this in young children."

He said surgeons should be judicious in using two-stage procedures. "I rarely do two-stage reconstructions," Waters said.

While the technique is similar to that in adults, children have twice the complication rate. Waters also highlighted the work of Frost and Cunningham, which cited potential growth problems with the procedure. "If you have a decreased force, you may actually not get de-differentiation in cells and you get growth development with digit differences in the longterm," he said.

For more information:
Waters PM. Pearls and pitfalls of pediatric tendon repairs. Precourse 6 Advances in bone, nerve and tendon surgery. Presented at the American Society for Surgery of the Hand 61st Annual Meeting. Sept. 7-9, 2006. Washington.
Peter M. Waters, MD, is with Boston Children's Hospital. He can be contacted at (617) 355-4849.