Jason T. Rhodes

The Role of Gait Analysis in Treating Gait Abnormalities in Cerebral Palsy

Individuals with cerebral palsy (CP) cannot take a normal activity like walking for granted. CP is the most common pediatric neurologic disorder, with an incidence of 3.6 per 1000 live births. The current trend in the treatment of individuals with CP is to perform a thorough evaluation including a complete patient history from birth to present, a comprehensive physical examination, appropriate radiographs, consultation with other medical specialists, and analysis of gait.

Delayed Anterior Cruciate Ligament Reconstruction in Young Patients With Previous Anterior Tibial Spine Fractures

Background: Avulsion fractures of the anterior tibial spine in young athletes are injuries similar to anterior cruciate ligament (ACL) injuries in adults. Sparse data exist on the association between anterior tibial spine fractures (ATSFs) and later ligamentous laxity or injuries leading to ACL reconstruction. Purpose: To better delineate the incidence of delayed instability or ACL ruptures requiring delayed ACL reconstruction in young patients with prior fractures of the tibial eminence. Study Design: Case series; Level of evidence, 4. Methods: We identified 101 patients between January 1993 and January 2012 who sustained an ATSF and who met inclusion criteria for this study. All patients had been followed for at least 2 years after the initial injury and were included for analysis after completion of a questionnaire via direct contact, mail, and/or telephone. If patients underwent further surgical intervention and/or underwent later ACL reconstruction, clinical records and operative reports pertaining to these secondary interventions were obtained and reviewed. Differences between categorical variables were assessed using the Fisher exact test. The association between time to revision ACL surgery and fracture type was assessed by Kaplan-Meier plots. The association between need for revision ACL surgery and age, sex, and mechanism of surgery was assessed using logistic regression. Results: Nineteen percent of all patients evaluated underwent delayed ACL reconstruction after a previous tibial spine fracture on the ipsilateral side. While there were a higher proportion of ACL reconstructions in type II fractures, there was not a statistically significant difference in the number of patients within each fracture group who went on to undergo later surgery (P = .29). Further, there was not a significant association between fracture type, sex, or mechanism of injury as it related to the progression to later ACL reconstruction. However, there was a significant association between age at the time of injury and progression to later ACL reconstruction (P = .02). For every year increase in age at the time of injury, the odds of going on to undergo delayed ACL reconstruction were greater by a factor of 1.3 (95% CI, 1.1-1.6). Conclusion: Although an ATSF is a relatively rare injury, our cohort of patients suggests that a subset of young patients with all types of tibial spine fractures will require later ACL reconstruction. There is a need to counsel patients that a delayed ACL rupture is a potential risk after an ATSF, especially as children approach skeletal maturity. Further patient follow-up and prospective studies are required.

Incidence of meniscal injury and chondral pathology in anterior tibial spine fractures of children.

Background: Pediatric avulsion fractures of the anterior tibial spine are injuries similar to anterior cruciate ligament injuries in adults. Sparse data exists on the association between anterior tibial spine fractures (ATSFs) and injury to the meniscus or cartilage of the knee joint in children. This research presents a retrospective review of clinical records, imaging, and operative reports to characterize the incidence of concomitant injury in cases of ATSFs in children. The purpose of this study was to better delineate the incidence of associated injuries in fractures of the anterior tibial spine in the pediatric population. Methods: We identified 58 patients who sustained an ATSF and met inclusion criteria for this study between 1996 and 2011. The subjects were separated by the Myers and McKeever classification into type I, II, and III fractures, and each of these were subclassified by associated injury pattern. Results: 59% of children with an ATSF had an associated soft tissue or other bony injury diagnosed by magnetic resonance imaging or arthroscopy. The most prevalent associated injuries were meniscal entrapment, meniscal tears, and chondral injury. We found no meniscal or chondral injury associated with type I fractures. Twenty-nine percent of type II injuries demonstrated meniscal entrapment, 33% showing meniscal tears. Seven percent demonstrated chondral injury. Forty-eight percent of type III fractures had entrapment, whereas 12% showed meniscal tears. Eight percent had a chondral injury. Conclusions: A majority (59%) of displaced ATSF had either concomitant meniscal, ligamentous, or chondral injury. This finding suggests that magnetic resonance imaging evaluation is an important aspect of the evaluation of these injuries, particularly in type II and type III patterns. To date, this study reports the largest number of patients to evaluate the specific question of concomitant injuries in ATSFs in the pediatric population. Level of Evidence: Level IV.

Passive Hip Range of Motion Predicts Femoral Torsion and Acetabular Version

BACKGROUND Orientation abnormalities of the acetabulum and femur have been implicated in early-onset coxarthrosis. The purpose of this study was to identify clinical examination findings predictive of such hip morphologies. METHODS A consecutive cohort of 221 patients (442 hips) undergoing hip arthroscopy was included. Demographic characteristics including age, diagnosis, sex, height, weight, body mass index (BMI), and physical activity level were recorded. Passive range of motion was measured for all hips. Preoperative computed tomography scans were utilized to measure femoral torsion and central acetabular version, and a combined femoral torsion-acetabular version (COTAV) index was defined as their sum. RESULTS The study cohort comprised 221 patients (sixty-four males, 157 females) with a mean age of 32.5 years and mean BMI of 24.2 kg/m(2). Overall, hips with femoral antetorsion and acetabular anteversion exhibited the greatest internal rotation range of motion at a neutral hip position (mean, 44.2°), whereas hips with femoral retrotorsion and acetabular retroversion demonstrated the lowest corresponding value (20.1°; p < 0.001). Femoral torsion was significantly associated with female sex (p < 0.001), BMI (p < 0.001), and presence of pathology corresponding to cam-type femoroacetabular impingement (FAI) (p = 0.044). Central acetabular version was significantly associated with age (p = 0.021), female sex (p < 0.001), and absence of mixed-type FAI pathology (p = 0.025). Increasing age and internal rotation range of motion at a neutral hip position were the most significant predictors of an increased COTAV index. CONCLUSIONS This study confirmed that passive hip range of motion significantly predicts combined femoral torsion and central acetabular version. Accurate clinical assessment of the COTAV index may inform surgical decision-making in hip preservation surgery.

Biomechanical Assessment of Patellar Advancement Procedures for Patella Alta

Crouch gait deformity is common in children with cerebral palsy and often is associated with patella alta. Patellar tendon advancement typically is used to correct patella alta and restore normal knee mechanics. The purpose of this study was to determine the mechanical strength of surgical constructs used for fixation during patellar advancement procedures. This study used a cadaveric model to determine which of 3 surgical techniques is biomechanically optimal for patellar tendon advancement in treating patella alta. Twenty-four human cadaveric knees (8 per group) were prepared using 1 of 3 different common surgical techniques: tibial tubercle osteotomy, patellar tendon partial resection and repair at the distal patella, and patellar tendon imbrication. The patella was loaded from 25 to 250 N at 1 Hz for 1000 cycles. A significant difference in patella displacement under cyclical loading was found between surgical techniques. Tibial tubercle osteotomy exhibited significantly less displacement under cyclical loading than distal patella excision and repair (P<.0001) or imbrication (P=.0088). Imbrication exhibited significantly less displacement than distal patella excision and repair (P=.0006). Tibial tubercle osteotomy survived longest. Based on failure criteria of 5 mm of displacement, tibial tubercle osteotomy lasted between 250 and 500 cycles. The other 2 techniques failed by 25 cycles. This study offers quantitative evidence regarding the relative mechanical strength of each construct and may influence choice of surgical technique. [Orthopedics. 2016; 39(3):e492-e497.].

The efficacy of intra-articular injections for pain control following the closed reduction and percutaneous pinning of pediatric supracondylar humeral fractures: a randomized controlled trial.

BACKGROUND The purpose of this single-blinded, randomized, controlled trial was to compare the analgesic efficacy of intra-articular injections of bupivacaine or ropivacaine with that of no injection for postoperative pain control after the operative treatment of supracondylar humeral fractures in a pediatric population. METHODS Subjects (n=124) were randomized to treatment with 0.25% bupivacaine (Group B) (n=42), 0.20% ropivacaine (Group R) (n=39), or no injection (Group C) (n=43). The opioid doses and the times of administration as well as child-reported pain severity (Faces Pain Scale-Revised) and parent-reported pain severity (Total Quality Pain Management survey) were recorded. RESULTS The proportion of subjects who required morphine and/or fentanyl injections was significantly (p=0.004) lower in Group B (10%) as compared with Group R (36%) and Group C (44%). On the basis of the log-rank test, the opioid-free survival rates were significantly greater in Group B as compared to Groups C and R. Total opioid consumption (morphine equivalent mg/kg) in the first seventy-two hours postoperatively was significantly less in Group B as compared with Group C (mean difference, 0.225; [95% confidence interval (CI), 0.0152 to 0.435]; p=0.036). Parent-reported pain scores were also significantly lower in Group B as compared with both Group C (mean difference, 1.81 [95% CI, 0.38 to 3.25]; p=0.014) and Group R (mean difference, 1.66; 95% CI, 0.20 to 3.12; p=0.027). There were no significant differences across the three groups in terms of self-reported pain. Differences between Groups R and C were not significant for any of the outcome variables. CONCLUSIONS The intra-articular injection of 0.25% bupivacaine significantly improves postoperative pain control following the closed reduction and percutaneous pinning of supracondylar humeral fractures in pediatric patients.

Outcomes of Isolated Varus Derotational Osteotomy in Children With Cerebral Palsy Hip Dysplasia and Predictors of Resubluxation.

Background: The appropriate intervention for hip subluxation or dislocation in children affected by cerebral palsy (CP) remains controversial. The purpose of this retrospective study was to report radiographic and clinical outcomes following isolated femoral varus derotational osteotomy (VDRO) in children with CP hip dysplasia. Risk factors for resubluxation and avascular necrosis (AVN) were also examined. Methods: A cohort of 100 patients (199 hips) with CP treated with isolated VDRO between 2003 and 2009 was reviewed. All but 1 patient received bilateral surgery. Patients were followed for an average of 5.4 years (range, 1.03 to 10.20 y). Anteroposterior pelvic radiographs were used to assess migration percentage (MP), Shenton’s line, and presence of AVN. Resubluxation was defined as a postoperative break in Shenton’s line. Radiographic outcomes and risk analysis was performed in the 91 subjects (179 hips) with radiographic follow-up >1 year. Results: Significant improvement was observed in MP, and all hips had a reconstituted Shenton’s line following surgery. Over the course of follow-up, 16% of hips were noted to have a repeat break in Shenton’s line. Univariate risk analysis showed preoperative MP, Gross Motor Function Classification System (GMFCS) level, and age at surgery were risk factors for a recurrent line break. Preoperative MP and GMFCS level were found to be predictors of resubluxation in multivariate analysis. AVN was detected in 10 hips (5.7%). GMFCS level V patients were more at risk for resubluxation, but less at risk for AVN when compared with ambulatory (GMFCS I/II/II) patients and GMFCS level IV patients. Conclusions: Performing a VDRO without additional procedures provided a stable and concentrically reduced hip joint in this population of children with CP. Attention should be paid to initial ambulatory status during the postoperative period. Concomitant procedures such as pelvic osteotomy should be considered for patients of GMFCS level IV and V, as these patients were more at risk for recurrent subluxation. Level of Evidence: Level III—retrospective comparative study.

Osteopenia of the hip joint in cerebral palsy - does this affect hip stability?

Osteopenia is very common in non-ambulatory patients with cerebral palsy (CP), evidenced by greater incidence with higher Gross Motor Function Classification System (GMFCS) level. Moon et al. have shown that patients with CP have decreased bone mineral density (BMD) that worsens as clinical CP involvement, GMFCS level, and hip instability increase. One risk associated with osteopenia in this population is that it can lead to fragility fractures, commonly in the distal femur and generally occurring with low impact activities, such as transfers, and during physical therapy. Understanding the risks of decreased BMD in these patients is essential for fracture prevention. It is very well accepted that decreasing the fracture rate associated with osteopenia would decrease morbidity issues for these patients and caregivers, but are there other clinical issues that are affected by osteopenia? Questions remain about the effects of osteopenia on hip stability, and about the structural stability of surgical reconstructive procedures commonly performed on these patients to prevent hip dislocation. There are various approaches to monitor BMD in patients with CP. Most commonly, dual-energy X-ray absorptiometry is used. Moon et al. evaluated the use of a 3-dimensional hip computed tomography (CT) examination to determine the bone attenuation of the acetabular and proximal femur. The goal was to determine what factors affected BMD in children below 18 years old with CP. One-hundred and twenty-six patients with CP and no prior hip surgery were compared to 86 normally developing participants. CT imaging was obtained retrospectively and bone attenuation was measured in the acetabulum and the femoral neck by an orthopaedic surgeon. The average Hounsfield units were calculated from data in those anatomical areas. The severity of hip instability was determined through migration percentage measured on radiographs, which according to Reimers and Bialik is the most common predictor of hip instability in patients with CP. This study shows that patients with CP have decreased BMD, and with lower BMD, the greater the neuromuscular involvement. This work does add to the literature by showing that with higher migration percentage there is a lower BMD, as measured through 3D CT Hounsfield units. Hip instability is common in CP and the more involved the CP, the more severe the risk of hip instability. This can lead to dislocation of the hip and resulting pain that hinders daily care, positioning, ambulation, physical therapy, and/or transfers. Moon et al. question if the observed decrease in BMD is caused from hip instability or if the hip instability is a result of the low BMD. Essentially, this work shows that there is a significant correlation between increased GMFCS and involvement of CP, with decreased BMD and increased hip instability in the patients with CP. This evidence adds to treatment consideration of osteopenia in patients with CP. While it is not proven that osteopenia affects hip instability, it is known that these patients have an increased risk of fragility fractures. These findings may affect treatment of hip instability, which can include osteotomies of the proximal femur (varus derotation osteotomy) and acetabuloplasty through a pelvic osteotomy. If the BMD is lower in the acetabulum will there be declines in structural competency, in turn potentially affecting operative fixation or long-term operative results? It is known that treatment of decreased BMD with weight-bearing activities, vitamin D and calcium supplementation, and bisphosphonate use in children with CP can reduce the risk of fragility fractures, but further research must be conducted to assess whether these treatments affect hip stability as measured by migration percentage, especially in severely involved non-ambulatory patients.

Pediatric and adolescent injury in skiing

ABSTRACT This review examines risks that accompany child and adolescent participation in downhill skiing. Falls and non-collision events were the most common mechanism of injury, but significant data implicate head injuries, blunt abdominal trauma, and spinal trauma as the leading causes of morbidity and mortality in this population. School-aged children and youth (7–14 years) are more likely to sustain an injury, compared to children (0–6 years) and older teenagers (15–17 years). Knee injuries were the most common injury, reported as 10.3%-47.7% of all lower limb injuries. The literature supports helmet use as protective against injury with a reduced risk of head, neck, or face injury in children under 13 years. Future studies are necessary to evaluate injury and risks in the backcountry given the rapid increase of adolescents traveling outside ski areas. Research examining risk factors and preventive measures in youth skiing is also warranted.

Mechanical Testing of Epiphysiodesis Screws

Epiphysiodesis is performed to treat leg-length discrepancies and angular deformities in children. However, when placed across a physis to modulate growth, screws can bend or break postoperatively. This study evaluated the mechanical properties of 3 different screw designs commonly used when performing an epiphysiodesis. Six 4.0-mm cannulated, fully threaded; six 4.0-mm cannulated, partially threaded; and six 4.0-mm noncannulated, partially threaded cancellous screws underwent cantilever bending and tension testing in a simulated physis. All screws were tested in simulated cancellous bone foam blocks. All testing was performed using a servo-hydraulic testing machine to determine stiffness and ultimate load. For statistical analysis, one-way analysis of variance with Tukeys honestly significant difference test in post hoc analysis was used to assess significant differences among groups (P<.05). The noncannulated, partially threaded screws had a significantly lower stiffness than the 2 cannulated screw types in the tension test (P<.001) and bending test (P<.001). Additionally, the noncannulated, partially threaded screws had significantly higher ultimate load to failure than the 2 cannulated screw types in the tension test (P<.001) and the cannulated, partially threaded screws in the bending test (P=.045). The results indicate that noncannulated, partially threaded screws have a higher ultimate load capacity and are less stiff than both cannulated, partially threaded screws and cannulated, fully threaded screws. Surgeons should take into consideration that noncannulated, partially threaded screws are less likely to fail following epiphysiodesis. [Orthopedics. 2018; 41(2):e240-e244.].