Published 1/18/2021
Kerri Fitzgerald

Immediate Weight Bearing Is Safe after Bony Surgery in Cerebral Palsy Patients

Editor’s note: The following content was originally scheduled for the AAOS Now Daily Edition, which publishes each year onsite at the AAOS Annual Meeting, but this year’s meeting in March was canceled due to COVID-19. Despite the cancellation, members can access virtual content from the Annual Meeting by visiting the Academy’s Annual Meeting Virtual Experience webpage at aaos.org/VirtualAAOS2020.

Studies assessing weight bearing following single-event, multilevel surgery have yielded variable findings; however, delayed weight bearing can result in weakness, recurrent contractures, loss of independence, social isolation, depression, and delayed rehabilitation.

A study that Andrew J. Abramowitz, MD, FAAOS, of the Maryland Pediatric Orthopedic Center in Baltimore, presented as part of the Annual Meeting Virtual Experience found that immediate weight bearing after bony surgery in ambulatory cerebral palsy patients is safe and effective, and the complication rate was no higher than that of historical cohorts.

“We propose that immediate postoperative weight bearing after bone procedures can lead to improvements in functional outcomes, decreased family burden of care, and lessened overall recovery time with minimal disadvantages and/or complications,” the authors noted of their findings.

“Years ago, when I began my cerebral palsy practice, I had to adjust my patients’ postoperative protocol from nonweight bearing to immediate weight bearing in order to admit them for acute rehabilitation postoperatively,” Dr. Abramowitz told AAOS Now. “Insurance would not allow an admission after nonweight bearing for the first six weeks postoperatively (which was what I was taught in fellowship) nor allow them to be admitted for any nonweight-bearing rehabilitation for any amount of time immediately after the acute inpatient hospital stay for surgery. Hence, I have been doing this for nearly 20 years and felt now was the time to report on it.”

The retrospective, longitudinal cohort study included 126 consecutive patients with ambulatory cerebral palsy (mean age, 13.67 years; range, 6–34 years; 77 patients were male) who underwent any surgery that included a bone procedure of the femur, tibia, and/or foot between 2004 and 2017. Eligible patients were treated by a single surgeon at a community hospital and had at least two years of postoperative follow-up. Patients with cerebral palsy who had bone surgery prior to six years of age and those who were not ambulatory were excluded.

All patients began standing on postoperative day one. Those without a foot procedure took steps by postoperative day two or three; those with a foot procedure took steps by day three after the cast was overwrapped. Both groups were weight bearing as tolerated from that point forward.

The researchers reviewed medical records and radiographs to determine the frequency and type of complications. They graded complications according to the modified Clavien-Dindo (MCD) classification system to identify any factors that impacted patient recovery, including wound issues (e.g., dehiscence); infection (superficial, deep, or osteomyelitis); delayed union, malunion, or nonunion; hardware issues; and loss of graft position (for calcaneal osteotomies). Medical complications included pain-related issues, urinary tract infections, and transfusions.

Among the cohort, 102 patients had bone osteotomies as part of a single-event, multilevel surgery; 36 patients had a single-bone procedure; and 90 had a multiple-bone procedure. Nineteen patients had unilateral and 107 had bilateral cerebral palsy.

Fifty-six patients had surgery unilaterally and 70 bilaterally. Among bilateral surgeries, 12 patients were staged initially having one leg done and then the other from 17 days to 11 months thereafter based on surgeon and/or patient preference. The average number of bone osteotomies performed on each patient was 2.75 (range, 1–6 osteotomies), and the average number of total procedures (including bone and soft tissue) was 7.07 (range, 1–18 procedures).

There were two iliac, 64 proximal femoral, 36 distal femoral extension, 19 tibial tubercle, 85 distal tibial, 83 calcaneal, 34 medial cuneiform, four first metatarsal, and four phalangeal osteotomies. There were nine naviculo-medial cuneiform, three talonavicular, nine subtalar, three calcaneocuboid, three first metatarsal-medial cuneiform, and three first metatarsophalangeal arthrodeses.

Complications observed

A total of 26 complications occurred, four of which “could possibly have resulted from immediate postoperative weight bearing,” according to the authors. Per MCD classification, there were 21 grade 1/2 complications. By definition, complications were minor and did not require major changes to care such as repeat surgery or readmission, including one nonunion of a naviculo-cuneiform fusion that was asymptomatic at nine years postoperatively and two malunions of proximal femoral osteotomies where both blade plates partially lost position in the proximal femur but did not impact postoperative outcomes. Other complications were related to wound problems, pain management, or transfusion.

There were no issues with epidurals or patient-controlled analgesia that required replacement or repositioning in the OR. There were four grade 3 complications, of which three were wound-related and one was screw-related and required a return to the OR. There were no cases of osteomyelitis, bone union issues, or graft problems requiring repeat trips to the OR. There was one grade 5 complication in a patient with known mitochondrial disorder who died from respiratory failure on postoperative day four.

By two years postoperatively, all patients with functional mobility scores were back to baseline, and there were no negative effects on postoperative functional mobility scores compared to other studies with delayed weight bearing.

“It is safe to immediately weight bear patients after bone surgery in ambulatory cerebral palsy patients with minimal to no complications as a result,” Dr. Abramowitz concluded. “The plan is for the next study to be a prospective cohort comparing centers that delay weight bearing to those that do it immediately postoperatively and [assess] complication rates, functional mobility scores, and costs (both realized and family burden of care) to see what postoperative protocol produces the best quality, safety, and value for this patient population.”

The study is limited by its retrospective design and heterogeneous population of ambulatory cerebral palsy patients (based on age, functional level, type of cerebral palsy, tone, and prior treatment).

Dr. Abramowitz’s coauthors of “Immediate Early Weight-Bearing Rehabilitation following Bone Procedures in Cerebral Palsy Patients” are Stephen A. Nichols, MD; and H. Kerr Graham, MD, FRCS, FRACS.

Kerri Fitzgerald is the managing editor of AAOS Now. She can be reached at kefitzgerald@aaos.org.