No abstract

Purpose of Review The orientation of the spine relative to the pelvis-particularly that in the sagittal plane-has been shown in both kinematic and radiographic studies to be paramount in governance of acetabular alignment during normal bodily motion. The purpose of this review is to better understand the challenges faced by arthroplasty surgeons in treating patients that have concurrent lumbar disease and are therefore more likely to have poorer clinical outcomes after THA than in patients without disease. Recent Findings The concept of an "acetabular safe zone" has been well described in the past regarding the appropriate orientation of acetabular component in THA. However, this concept is now under scrutiny, and rising forth is a concept of functional acetabular orientation that is based on clinically evaluable factors that are patient and motion specific. Summary The interplay between the functional position of the acetabulum and the lumbar spine is complex. The challenges that are thereby faced by arthroplasty surgeons in terms of proper acetabular cup positioning when treating patients with concomitant lumbar disease need to be better understood and studied, so as to prevent catastrophic and costly complications such as periprosthetic joint dislocations and revision surgeries.

The lateral column lengthening procedure is a commonly used osteotomy for correction of pes planus performed by inserting a graft in the anterior aspect of the calcaneus through a transverse osteotomy. Though nonunion and calcaneo-cuboid subluxation have been previously reported, these complications have not been extensively studied in pediatric patients. After IRB approval, 111 patients (151 feet) who underwent lateral column lengthening at a single institution were identified. Fifty-three females (70 feet) and 58 males (81 feet) with an average age of 11.4 years (2.6 SD; range 5–17) were analyzed. The primary outcome was nonunion defined as a lack of radiographic evidence of osteotomy healing by 9 months. Underlying diagnosis, pre and postoperative radiographic measurements, age, operative technique, fixation, calcaneo-cuboid subluxation, graft material and concomitant procedures were analyzed for their relationship to nonunion. Nonunion occurred in 7 of 151 feet (4.6%). Patient age at the time of surgery and calcaneo-cuboid subluxation trended toward a significant association with nonunion (P = 0.053, 0.054, respectively). The degree of surgical correction, as determined by radiographic analysis, and the use of calcaneo-cuboid fixation were not significantly associated with nonunion. None of the other factors evaluated were significantly associated with nonunion. There were three cases of postoperative infections (2.0%), two were superficial and 1 (0.7%) was deep. Thirty-five of 151 feet disclosed radiographic evidence of subluxation. Excluding subluxation, the overall complication rate was 8.6%. Nonunion occurred in 4.6% of pediatric feet undergoing lateral column lengthening. Fixation type was not significantly associated with nonunion. Older age at the time of surgery and calcaneocuboid subluxation trended towards significance. The placement of a calcaneo-cuboid pin was not found to be a significant factor in preventing calcaneo-cuboid subluxation or nonunion.

BACKGROUND Neuromuscular scoliosis is commonly associated with a large pelvic obliquity. Scoliosis in children with cerebral palsy is most commonly managed with posterior spinal instrumentation and fusion. While consensus is reached regarding the proximal starting point of fusion, controversy exists as to whether the distal level of spinal fusion should include the pelvis to correct the pelvic obliquity. AIM To assess the role of pelvic fusion in posterior spinal instrumentation and fusion, particularly it impact on pelvic obliquity correction, and to assess if the rate of complications differed as a function of pelvic fusion. METHODS This was a retrospective, cohort study in which we reviewed the medical records of children with cerebral palsy scoliosis treated with posterior instrumentation and fusion at a single institution. Minimum follow-up was six months. Patients were stratified into two groups: Those who were fused to the pelvis and those fused to L4/L5. The major outcomes were complications and radiographic parameters. The former were stratified into major and minor complications, and the latter consisted of preoperative and final Cobb angles, L5-S1 tilt and pelvic obliquity. RESULTS The study included 47 patients. The correction of the L5 tilt was 60% in patients fused to the pelvis and 67% in patients fused to L4/L5 ( P = 0.22). The pelvic obliquity was corrected by 43% and 36% in each group, respectively ( P = 0.12). Regarding complications, patients fused to the pelvis had more total complications as compared to the other group (63.0% vs 30%, respectively, P = 0.025). After adjusting for differences in radiographic parameters (lumbar curve, L5 tilt, and pelvic obliquity), these patients had a 79% increased chance of developing complications (Relative risk = 1.79; 95%CI: 1.011-3.41). CONCLUSION Including the pelvis in the distal level of fusion for cerebral palsy scoliosis places patients at an increased risk of postoperative complications. The added value that pelvic fusion offers in terms of correcting pelvic obliquity is not clear, as these patients had similar percent correction of their pelvic obliquity and L5 tilt compared to children whose fusion was stopped at L4/L5. Therefore, in a select patient population, spinal fusion can be stopped at the distal lumbar levels without adversely affecting the surgical outcomes.

Category: Hindfoot Introduction/Purpose: The Evans/Mosca procedure remains the most utilized extra-articular osteotomies for correction of pes planus. This desired lengthening is created by inserting a graft in the anterior aspect of the calcaneus through a complete transverse osteotomy. Failure of conservative methods, particularly for rigid pes planus, is a primary consideration for surgical management. Complications of the Evans procedure include delayed union, nonunion, malunion, subluxation of the calcaneocuboid joint, and persistent lateral column pain. Our study analyzes risk factors for development of non-union. Methods: After IRB approval 120 patients charts and 157 feet were analyzed for incidence of non-union which was defined by clinical and radiographic evidence of absence of union >6 months. Delayed union was diagnosed if there was clinical evidence of healing without complete union at >6 months. Exclusion criteria included age >18 and revision lateral column lengthening. Patients' medical records were reviewed for basic demographics, complications, and surgical technique. Results: The cohort consisted of 75 females (47.8%) and 82 males (52.2%). The median age was 12 with an interquartile range (IQR) of 3. A total of 6 patients (3.7%) had wound complications or nerve injury. Nonunion occurred in 7 of 157 feet (4.5%) with 2 of 157 feet (1.3%) experiencing delayed union. The median age for patients with nonunion was significantly higher than those who achieved union (13.2 (IQR 2.75) vs. 11.2 (IQR 3) respectively). The fixation construct used was associated with increased risk of nonunion. Patients with screw fixation had the highest rate of nonunion at 50% (2/2) compared to pin and/or staple fixation at 6.8% (5/73), no fixation at 4% (3/75), and plate fixation at 0% (0/2). Both delayed union patients were treated with ultrasound bone stimulation, both patients were able to achieve complete union. Revision was attempted in 5/7 nonunions with all operative patients achieving union. Conclusion: Our study analyzed risk factors for developing non-union in patients undergoing calcaneal lengthening osteotomy for pediatric pes planus. We found age at time of surgery and graft fixation method to be significant risk factors for development of non-union. Our study highlighted that those patients who had non-union was on average >2yrs older at time of surgery. Overall, lateral column lengthening is a well-tolerated procedure with a complication rate, including non-and delayed union, of 10.8%. Surgeons should be aware, in the largest cohort of pediatric Evans/Mosca procedures to date, patient age and type of fixation were associated with nonunion.