Predicting Rates of Angular Correction After Hemiepiphysiodesis in Patients With X-Linked Hypophosphatemic Rickets.

PURPOSE: Patients with X-linked hypophosphatemic rickets (XLH) often develop coronal plane knee deformities despite medical treatment. Hemiepiphysiodesis is an effective way to correct coronal plane knee deformities in skeletally immature patients, but a full understanding of the rate of angular correction after hemiepiphysiodesis in XLH patients, compared with idiopathic cases is lacking. METHODS: We retrospectively reviewed charts of 24 XLH patients and 37 control patients without metabolic bone disease who underwent hemiepiphysiodesis. All patients were treated with standard-of-care medical therapy (SOC=active vitamin D and phosphate salt supplementation) in our clinical research center and had a minimum of 2-year follow-up after hemiepiphysiodesis. Demographic data as well as complications, repeat procedures, or recurrence/overcorrection were recorded. Standing lower extremity radiographs were evaluated before the surgical intervention and at subsequent hardware removal or skeletal maturity, whichever came first. Mean axis deviation, knee zone, mechanical lateral distal femoral angle (mLDFA), and medial proximal tibial angle were measured on each radiograph. The rate of angular correction was calculated as the change in mLDFA and medial proximal tibial angle over the duration of treatment. RESULTS: The magnitude of the initial deformity of the distal femur was greater in XLH patients as compared with control for varus (XLH mLDFA 97.7 +/- 4.9 vs. Control mLDFA 92.0 +/- 2.0 degrees) and valgus (XLH mLDFA 78.7 +/- 6.2 vs. Controls mLDFA 83.6 +/- 3.2 degrees). The rate of correction was dependent on age. When correcting for age, XLH patients corrected femoral deformity at a 15% to 36% slower rate than control patients for the mLDFA (>3 y growth remaining XLH 0.71 +/- 0.46 vs. control 0.84 +/- 0.27 degrees/month, <3 y growth remaining XLH 0.37 +/- 0.33 vs. control 0.58 +/- 0.41 degrees/month). No significant differences were seen in the rate of proximal tibia correction. XLH patients were less likely to end treatment in zone 1 (55.0% XLH vs. 77.8% control). XLH patients had longer treatment times than controls (19.5 +/- 10.7 vs. 12.6 +/- 7.0 mu, P value <0.001), a higher average number of secondary procedures than controls (1.33 +/- 1.44 vs. 0.62 +/- 0.92 number of procedures), a higher rate of overcorrection than controls (29.2% vs. 5.4%), and a higher rate of subsequent corrective osteotomy than controls (37.5% vs. 8.1%). There was no significant difference in the rate of complications between groups (8.3% vs. 5.4%). CONCLUSIONS: Patients with XLH undergoing hemiepiphysiodesis have a 15% to 36% slower rate of femoral deformity correction that results in longer treatment times, a higher likelihood to undergo more secondary procedures, and a lower likelihood to reach neutral mechanical alignment. SIGNIFICANCE: This study provides important information to guide the timing and treatment of patients with XLH and coronal plane knee deformities. In addition, results from this study can be educational for families and patients with respect to anticipated treatment times, success rates of the procedure, complication rate, and likelihood of needing repeat procedures.

Severe Hip Dysplasia in Skeletally Mature Patients With Spastic Cerebral Palsy: The Technique and Early Outcome of Comprehensive Surgical Correction (Including the Bernese PAO).

BACKGROUND: Treatment of symptomatic hip dysplasia in skeletally mature patients with spastic cerebral palsy (CP) can be challenging. This study examines our technical experience with the Bernese periacetabular osteotomy (PAO) in combination with adjunctive procedures in the treatment of this complex hip deformity. METHODS: Sixteen consecutive patients (18 hips) with symptomatic CP hip dysplasia were treated with a PAO and variable adjunctive procedures and retrospectively reviewed. Two patient (2 hips) were excluded due to insufficient follow-up. The average age at the time of surgery was 17.7 years (range: 13 to 28 y). We compared the preoperative to postoperative changes in radiographic parameters as well as early outcomes as measured by patient assessment of hip pain and function using the modified Harris Hip Score (mHHS). RESULTS: The average time of follow-up was 3.3 years (range: 2.0 to 6.3 y). Tönnis angles decreased from a median of 30 degrees (range: 18 to 45 degrees) preoperatively to a median of 6 degrees (range: -9 to 21 degrees) postoperatively. Lateral center-edge angles increased from a median of -8 degrees (range: -28 to 15 degrees) to a median of 32 degrees (range: 19 to 38 degrees). Anterior center-edge angles increased from a median of 2 degrees (range: -22 to 39 degrees) to a median of 35 degrees (range: 22 to 47 degrees). The extrusion index decreased from a median of 57% preoperatively (range: 35% to 73%) to a median of 21% (range: 11% to 36%) postoperatively.The median mHHS was 62 (range: 37 to 81) preoperatively and 85 (range: 65 to 100) postoperatively. Notably, the pain component of the mHHS improved from 20 (range: 0 to 44) to 42 (range: 30 to 44). Tönnis osteoarthritis grade preoperatively was either 0 (11 hips) or 1 (5 hips) and remained unchanged in 11 hips and increased by 1 grade in 5 hips. CONCLUSIONS: It has been our experience that the Bernese PAO in combination with appropriate adjunctive treatments has provided a very satisfactory surgical approach in the treatment of CP hip dysplasia. In the adolescent and young adult with spastic CP, utilizing the Bernese PAO technique makes it possible to obtain redirection of often a very severe acetabular dysplasia. Adjunctive soft tissue procedures and a proximal femoral osteotomy are frequently necessary to maintain postoperative stability. A notable improvement in the quality of life and function directly attributable to our surgical treatment of their pre-existing problematic hip dysplasia has been consistently noted in early follow-up for our patients. LEVEL OF EVIDENCE: Level IV-therapeutic.

Open Reduction and Internal Fixation for the Treatment of Symptomatic Osteochondritis Dissecans of the Femoral Head in Patients With Sequelae of Legg-Calvé-Perthes Disease.

BACKGROUND: Osteochondritis dissecans (OCD) is estimated to occur in 2% to 7% of patients with Legg-Calvé-Perthes disease (LCPD). Unstable osteochondral fragments secondary to LCPD may produce mechanical symptoms requiring surgical intervention. Reattachment of the fragment with open reduction and internal fixation (ORIF) may provide good clinical outcomes. The purpose of this study is to report short-term clinical and radiographic results of ORIF for the treatment of symptomatic osteochondral lesions resulting from LCPD. METHODS: Clinical data including patient demographics and patient-reported outcome scores were collected prospectively. All patients underwent preoperative radiographs and magnetic resonance imaging confirming an unstable OCD fragment as well as postoperative radiographs at regular intervals. Indications for ORIF of the OCD fragment were hip pain and mechanical symptoms with radiographic evidence of LCPD and a magnetic resonance imaging demonstrating an OCD fragment of the femoral head. Osteochondral fragment instability was confirmed intraoperatively. Preoperative and postoperative physical examination findings were documented. All patients failed a course of nonsurgical treatment (activity modification, anti-inflammatories, and physical therapy). RESULTS: From a total of 64 consecutive patients treated with hip preservation surgery for LCPD, 7 patients with symptomatic OCD secondary to LCPD were treated with surgical hip dislocation and ORIF of the femoral head osteochondral fragment. OCD size lesion ranged from 200 to 625 mm. All patients reported marked clinical improvement, with resolution of both pain and mechanical symptoms. Radiographs at final follow-up demonstrated complete osteochondral fragment healing without implant failure. Mean follow-up was 4.6 years (range, 1.1 to 7.4 y). There was a significant postoperative improvement in measured internal rotation in flexion (5.0±5.0 to 16.4±9.8; P=0.02). Modified Harris Hip Score markedly improved from baseline to final follow-up (47.8 to 82.7; [INCREMENT]34.9; minimal clinically important difference, 11; P=0.002), with all patients meeting minimal clinically important difference for modified Harris Hip Score. There were no complications and no progression of osteoarthritis in all patients at final follow-up. CONCLUSIONS: We have demonstrated both predictable radiographic healing and marked clinical improvement following ORIF of symptomatic post-Perthes OCD lesions. We advocate ORIF for symptomatic osteochondral lesions as a first-line surgical treatment for these patients due to the advantages of native osteochondral tissue preservation, predictable healing, and marked clinical improvement. LEVEL OF EVIDENCE: Level IV-case series.

Determining Hinge Abduction in Legg-Calvé-Perthes Disease: Can We Reliably Make the Diagnosis?

BACKGROUND: Although hinge abduction is recognized as an important finding in children with Legg-Calvé-Perthes disease, variable diagnostic criteria exist. The purpose of this study was (1) to test the interobserver and intraobserver agreement of the current definition of hinge abduction and (2) to develop consensus regarding key diagnostic features that could be used to improve our diagnostic criteria. METHODS: Four orthopaedic surgeons with subspecialty pediatric hip interest independently assessed 30 randomly ordered cases of Legg-Calvé-Perthes disease. Each case included 2 fluoroscopic images of hip arthrograms (anteroposterior and abduction views). Surgeons graded the cases in a binary manner (hinge/no-hinge) on 2 separate occasions separated by a 4-week interval. Following reliability testing and comprehensive review of the literature, consensus-building sessions were conducted to identify key diagnostic features. Surgeons then regraded a new series of cases. Interobserver and intraobserver agreement between first/second and third/fourth readings were assessed using the Fleiss κ. RESULTS: Interobserver κ for hinge abduction between the first and second surveys was 0.52 (with 0.41 to 0.60 considered moderate agreement), compared with 0.56 for the third and fourth surveys. First and second reading intraobserver agreement ranged from 0.59 to 0.83 compared with 0.75 to 1.00 for third and fourth reading. Consensus sessions identified several key diagnostic factors including: adequate visualization of the labral contour and ability of the lateral epiphysis to slip below the chondrolabral complex in abduction. Medial dye pooling, often due to asphericity of the femoral head, was not found to be a useful diagnostic criterion. CONCLUSIONS: Despite a combined experience of over 70 years among the reviewers, we found just slightly better than 50:50 agreement in what constitutes hinge abduction. Consensus discussions did improve our agreement but these modest changes emphasize how difficult it is to develop reliable diagnostic criteria for hinge abduction. As a result, we caution against using hinge abduction as an inclusion criteria or outcome measure for research purposes, as the diagnostic agreement can be inconsistent. LEVEL OF EVIDENCE: Level III-diagnostic study.

Knee Pain and Activity Outcomes After Femoral Derotation Osteotomy for Excessive Femoral Anteversion.

BACKGROUND: Excessive femoral anteversion is a developmental condition that can become symptomatic into adolescence and manifest as anterior knee pain, tripping, and or problems with sports. Femoral derotational osteotomy about an antegrade intramedullary nail (IMN) is an accepted option to treat this condition. This is the first report of the clinical and functional outcomes of treatment of excessive anteversion with femoral derotational osteotomy stabilized with an IMN. METHODS: We prospectively enrolled 28 consecutive patients between 2013 and 2014 who underwent derotational osteotomy. Physical examination measures were used to calculate the amount of angular correction with focus on internal and external rotation of the hip, as well as the trochanteric prominence angle test of femoral anteversion. The International Knee Documentation Committee-9, Marx, and Tegner activity scales were 3 patient-reported outcomes recorded. RESULTS: After femoral derotation osteotomy over an IMN, femoral anteversion, as measured by the trochanteric prominence angle, improved an average of 29 degrees (P<0.0001). At 1-year minimum follow-up, 22 of 28 subjects (78.5%) demonstrated a mean significant improvement of 13 points for International Knee Documentation Committee-9 (SD=15.4, P=0.0007), which surpassed the level of minimal clinically important change. Furthermore, the Tegner inventory scores for the cohort improved by an average of 1.9 activity levels (SD=2.4, P=0.0012). CONCLUSIONS: For adolescents with symptomatic excessive femoral anteversion, derotational osteotomy over an IMN offers a reliable surgical option that provides predictable deformity correction and significant improvements in both function and pain scales. LEVELS OF EVIDENCE: Level II-prospective, consecutive, nonrandomized, internally controlled cohort study.

Do Radiographic Parameters of Dysplasia Improve to Normal Ranges After Bernese Periacetabular Osteotomy?

BACKGROUND: The goal of periacetabular osteotomy (PAO) is to improve the insufficient coverage of the femoral head and achieve joint stability without creating secondary femoroacetabular impingement. However, the complex tridimensional morphology of the dysplastic acetabulum presents a challenge to restoration of normal radiographic parameters. Accurate acetabular correction is important to achieve long-term function and pain improvement. There are limited data about the proportion of patients who have normal radiographic parameters restored after PAO and the factors associated with under- and overcorrection. QUESTIONS/PURPOSES: (1) What is the proportion of patients undergoing PAO in which the acetabular correction as assessed by the lateral center-edge angle (LCEA), anterior center-edge angle (ACEA), acetabular inclination (AI), and extrusion index (EI) is within defined target ranges? (2) What patient and preoperative factors are associated with undercorrection of the acetabulum as defined by a LCEA < 22°, a factor that has been reported to be associated with PAO failure at 10-year followup? METHODS: Between January 2007 and December 2011 we performed 132 PAOs in 116 patients for treatment of symptomatic acetabular dysplasia. One patient with Legg-Calvé-Perthes disease, one with multiple osteochondromatosis, and two with concomitant femoral osteotomy were excluded. A total of 128 hips (112 patients) were included. The hip cohort was 76% (97 of 128) female and the mean age at surgery was 28.5 years (SD 8.7 years). Correction of LCEA between 25° and 40°, ACEA between 18° and 38°, Tönnis angle between 0° and 10°, and EI ≤ 20% were defined as adequate based on normative values. Values lower than the established parameters were considered undercorrection for the LCEA and ACEA and those higher than the established values were considered overcorrection. Because postoperative LCEA < 22o has been previously associated with PAO failure at a minimum of 10-year followup, in this study we sought to measure whether demographic factors including age, gender, body mass index, and severity of acetabular dysplasia assessed by preoperative LCEA, ACEA, AI, and EI were associated with undercorrection. Postoperative radiographs were obtained at minimum of 1 month after surgery (mean, 7 months; range, 1-44 months) and were measured by a professional research assistant and a hip reconstruction fellow not involved in the clinical care of the patients. No patient was lost to followup. RESULTS: Of the 128 hips, the proportion of hips with radiographic parameters within the established range was 78% (100 hips) for the LCEA, 86% (110 hips) for the ACEA, 89% (114 hips) for the AI, and 80% (102 hips) for the EI. For hips with an inadequate correction, the LCEA was more often undercorrected than overcorrected (20% versus 2%; 95% confidence interval [CI], 11%-27%; p < 0.001), whereas the ACEA was more often overcorrected than undercorrected (11% versus 3%; 95% CI, 1%-15%; p = 0.03) After adjusting for age, sex, body mass index, and preoperative radiographic parameters including ACEA, AI, and EI, we found that the preoperative LCEA was the only independent factor associated with a postoperative LCEA < 22° (odds ratio, 0.92; 95% CI, 0.87-0.97; p = 0.003), indicating that hips with lower preoperative LCEA were more likely to have a LCEA < 22°. For each additional degree of preoperative LCEA, the odds of LCEA < 22° were reduced by 15%. CONCLUSIONS: Acetabular correction after PAO performed by two experienced surgeons was adequate for individual radiographic parameters in most but not all hips. Hips with more severe dysplasia preoperatively are at higher risk for undercorrection as assessed by the LCEA. This intuitive information may help surgeons performing PAO in severely dysplastic hips plan for possible combined procedures including a femoral osteotomy if PAO alone does not allow for adequate correction of femoral head coverage and a congruous concentric hip. Further studies are planned to determine whether the long-term hip function and pain in patients whose hips were corrected within these established parameters will be improved in comparison to those that were under- or overcorrected. LEVEL OF EVIDENCE: Level III, therapeutic study.

Three Patterns of Acetabular Deficiency Are Common in Young Adult Patients With Acetabular Dysplasia.

BACKGROUND: Detailed recognition of the three-dimensional (3-D) deformity in acetabular dysplasia is important to help guide correction at the time of reorientation during periacetabular osteotomy (PAO). Common plain radiographic parameters of acetabular dysplasia are limited in their ability to characterize acetabular deficiency precisely. The 3-D characterization of such deficiencies with low-dose CT may allow for more precise characterization. QUESTIONS/PURPOSES: The purposes of this study were (1) to determine the variability in 3-D acetabular deficiency in acetabular dysplasia; (2) to define subtypes of acetabular dysplasia based on 3-D morphology; (3) to determine the correlation of plain radiographic parameters with 3-D morphology; and (4) to determine the association of acetabular dysplasia subtype with patient clinical characteristics including sex, range of motion, and femoral version. METHODS: Using our hip preservation database, we identified 153 hips (148 patients) that underwent PAO from October 2013 to July 2015. Among those, we noted 103 hips in 100 patients with acetabular dysplasia (lateral center-edge angle < 20°) and who had a Tönnis grade of 0 or 1. Eighty-six patients (86%) underwent preoperative low-dose pelvic CT scans at our institution as part of the preoperative planning for PAO. It is currently our standard to obtain preoperative low-dose pelvic CT scans (0.75-1.25 mSv, equivalent to three to five AP pelvis radiographs) on all patients before undergoing PAO unless a prior CT scan was performed at an outside institution. Hips with a history of a neuromuscular disorder, prior trauma, prior surgery, radiographic evidence of joint degeneration, ischemic necrosis, or Perthes-like deformities were excluded. Fifty hips in 50 patients met inclusion criteria and had CT scans available for review. These low-dose CT scans of 50 patients with symptomatic acetabular dysplasia undergoing evaluation for surgical planning of PAO were then retrospectively studied. CT scans were analyzed quantitatively for acetabular coverage, relative to established normative data for acetabular coverage, as well as measurement of femoral version. The cohort included 45 females and five males with a mean age of 26 years (range, 13-49 years). RESULTS: Lateral acetabular deficiency was present in all patients, whereas anterior deficiency and posterior deficiency were variable. Three patterns of acetabular deficiency were common: anterosuperior deficiency (15 of 50 [30%]), global deficiency (18 of 50 [36%]), and posterosuperior deficiency (17 of 50 [34%]). The presence of a crossover sign or posterior wall sign was poorly predictive of the dysplasia subtype. With the numbers available, males appeared more likely to have a posterosuperior deficiency pattern (four of five [80%]) compared with females (13 of 45 [29%], p = 0.040). Hip internal rotation in flexion was significantly greater in anterosuperior deficiency (23° versus 18°, p = 0.05), whereas external rotation in flexion was significantly greater in posterosuperior deficiency (43° versus 34°, p = 0.018). Acetabular deficiency pattern did not correlate with femoral version, which was variable across all subtypes. CONCLUSIONS: Three patterns of acetabular deficiency commonly occur among young adult patients with mild, moderate, and severe acetabular dysplasia. These patterns include anterosuperior, global, and posterosuperior deficiency and are variably observed independent of femoral version. Recognition of these distinct morphologic subtypes is important for diagnostic and surgical treatment considerations in patients with acetabular dysplasia to optimize acetabular correction and avoid femoroacetabular impingement.

Are there sex-dependent differences in acetabular dysplasia characteristics?

BACKGROUND: Many patients who undergo periacetabular osteotomy (PAO) for symptomatic acetabular dysplasia experience decreased pain and improved function, yet some experience inadequate clinical improvement. The etiologies of treatment failure have not been completely defined, and sex-dependent disease characteristics that may be associated with less pain relief are not understood. QUESTION/PURPOSES: We sought to determine whether there were clinically important sex-specific differences between male and female patients undergoing PAO for acetabular dysplasia in terms of (1) clinical parameters (anthropomorphic traits and hip scores), (2) radiographic findings, and (3) intraoperative findings at the time of PAO, in particular findings potentially associated with femoroacetabular impingement (FAI) such as chondromalacia at the head-neck junction, impingement trough, or reduced head-neck offset. METHODS: Between 2007 and 2012 we treated 245 patients (270 hips) with a PAO for symptomatic acetabular dysplasia. Of those, 16 patients (16 hips; 6%) had insufficient documentation for review in the medical record and another 49 patients (51 hips; 19%) met prespecified exclusion criteria, leaving 180 patients (203 hips; 75%) for analysis in this retrospective study. One hundred thirty-nine patients were females and 41 were males. Clinical data including patient demographics, physical examination, patient self-reported outcome scores, radiographic morphologic features, and intraoperative findings were collected prospectively as part of an institutional registry. Statistical analysis was performed with univariate and multivariate analyses. RESULTS: Mean age was similar among sexes; however, BMI was greater in males compared with females (26 versus 24 kg/m(2); p = 0.002). Males had less hip ROM including internal rotation at 90° flexion (14° ± 13.8° versus 25° ± 16.2°; p = 0.001). Males had higher preoperative UCLA (7 ± 2, versus 6 ± 2; p = 0.02) and Harris hip scores (63 ± 15 versus 58 ± 16; p = 0.04). Radiographically, a crossover sign (88% versus 39%; p < 0.001) and posterior wall sign (92% versus 63%; p < 0.001) were more common in males. Males had greater alpha angles on the frog lateral (63° ± 15.3° versus 58° ± 16°; p = 0.04) and Dunn radiograph views (64° ± 15.5° versus 56° ± 14.8°; p = 0.02). The incidence of femoral head-neck chondromalacia (62% versus 82%; p = 0.03) and an impingement trough observed at surgery was greater in males (35% versus 17%; p = 0.01). Multivariate analysis showed differences between the sexes for reduced internal rotation in flexion, a higher Dunn alpha angle, increased incidence of a crossover sign, and a lower anterior center-edge angle. CONCLUSIONS: There are sex-dependent, disease characteristic differences in patients with symptomatic acetabular dysplasia. Most notably, male patients have a greater prevalence of clinical, radiographic, and intraarticular findings consistent with concurrent FAI and instability and potentially a heightened risk of secondary FAI after PAO, however postoperative and long-term followup are needed to confirm these findings and it remains unclear which patients need surgical correction of the impingement and instability. Preoperative evaluation of acetabular dysplasia in males should at least include careful attention to factors associated with symptomatic FAI; however, further studies are needed to determine when surgical correction is needed.

Does Tranexamic Acid Reduce Blood Loss and Transfusion Requirements Associated With the Periacetabular Osteotomy?

BACKGROUND: Tranexamic acid (TXA) has shown safety and efficacy in reducing blood loss associated with various surgical procedures. However, to our knowledge there are no studies evaluating the effect of TXA on blood loss and transfusion requirements associated with periacetabular osteotomy (PAO). QUESTIONS/PURPOSES: The main purpose of this study is to determine whether TXA reduces blood loss and transfusion use in patients undergoing PAO for symptomatic acetabular dysplasia. Our secondary purpose was to compare the frequency of symptomatic thromboembolic events between patients undergoing surgery with and without TXA. METHODS: A consecutive series of 100 periacetabular osteotomies performed by one surgeon was reviewed to compare the groups immediately before and after implementation of routine use of tranexamic acid (two retrospective cohorts). TXA dosing followed an established protocol with a standard dose of 1 g infused intravenously during 10 minutes before skin incision and an additional 1 g intravenously at wound closure. Outcome measures include total estimated blood loss perioperatively and transfusion requirements. Total estimated blood loss was calculated using a formula built from the National Surgical Quality Improvement Program data regarding surgical blood loss. RESULTS: The mean perioperative total estimated blood loss was less in the patients receiving TXA compared with blood loss in patients who did not receive TXA (706 mL versus 1021 mL; p<0.001; 95% CI, -495 to -134). Twenty-six (52%) of the 50 patients who did not receive TXA had postoperative blood transfusions compared with 15 (30%) of 50 who received TXA (odds ratio, 0.395; 95% CI, 0.174-0.899; p=0.0414). No symptomatic deep vein thromboses or symptomatic pulmonary emboli were identified in either group. CONCLUSIONS: TXA reduces estimated blood loss and the frequency of transfusions in patients undergoing PAO for treatment of symptomatic acetabular dysplasia. Future prospective studies should confirm our findings to determine whether patients undergoing PAO should receive routine perioperative TXA. LEVEL OF EVIDENCE: Level III, therapeutic study.

Does surgical hip dislocation and periacetabular osteotomy improve pain in patients with Perthes-like deformities and acetabular dysplasia?

BACKGROUND: Patients with symptomatic residual Perthes-like deformities may present with a combination of structural abnormalities including a large aspheric femoral head, short and wide femoral neck, high greater trochanter, and acetabular dysplasia. Sometimes, the hip is further compromised by concurrent symptomatic femoroacetabular impingement (FAI) (proximal femoral deformities) and structural instability (acetabular dysplasia). QUESTIONS/PURPOSES: We therefore sought to characterize (1) the intraoperative findings; (2) radiographic correction; and (3) early patient-reported outcomes, complications, and failures of treating complex Perthes-like hip deformities with combined surgical dislocation and periacetabular osteotomy (PAO). METHODS: We performed 694 hip preservation procedures between November 2006 and August 2010. Of these, 46 had residual Perthes-like hip deformities, defined as proximal deformity consistent with residual Perthes and a history of Perthes disease or treatment of pediatric hip dysplasia. Of these, we report on 16 patients (16 hips) with residual Perthes-like hip deformities and associated acetabular dysplasia (structural instability, defined as radiographic evidence of acetabular dysplasia with intraoperative confirmation of instability). These 16 patients were treated with a combined surgical hip dislocation to comprehensively address intraarticular and extraarticular sources of FAI and PAO to address structural instability and were analyzed at a minimum 24-month followup (median, 40 months; range, 24-78 months). No patients in this series were lost to followup. Ten patients' hips had previous surgical treatment, including six with previous osteotomy. Operative findings were extracted from standardized prospectively collected intraoperative data collection forms. Radiographic correction was evaluated with established methods (lateral center-edge angle, anterior center-edge angle, acetabular inclination, center-to-trochanter distance) and clinical outcomes were measured with the modified Harris hip score (mHHS) as well as by prospectively recorded data on patient complications and followup. RESULTS: Acetabular labrochondral abnormalities included labral hypertrophy in all hips and labral and/or articular cartilage lesions requiring treatment in 13 hips. Radiographic analysis demonstrated consistent radiographic correction. The median preoperative mHHS improved from 64 to 92 at a median followup of 40 months (p < 0.001). Fourteen patients (14 hips) had a good or excellent clinical result. Two patients (two hips) were classified as failures based on mHHS less than 70 (n = 1) or conversion to total hip arthroplasty (n = 1). CONCLUSIONS: Combined surgical hip dislocation and PAO provides major deformity correction in Perthes-like hip deformities with associated acetabular dysplasia. Early clinical results suggest this technique is safe and effective. Long-term studies are needed to determine if improved long-term outcomes are associated with comprehensive deformity correction.

Does previous pelvic osteotomy compromise the results of periacetabular osteotomy surgery?

BACKGROUND: As the Bernese periacetabular osteotomy (PAO) has grown in popularity, specific indications and the results in patients treated for those indications need to be evaluated. Currently, although many patients undergo PAO after having had prior pelvic osteotomy, there is limited information regarding the efficacy of the PAO in these patients. QUESTIONS/PURPOSES: The purpose of this study was to compare the (1) early pain, function, activity, and quality of life outcomes; (2) radiographic correction; and (3) major complications and failures between patients who underwent PAO after prior pelvic reconstruction versus those who had a PAO without prior surgery. METHODS: Between February 2008 and January 2012, 39 patients underwent PAO after prior pelvic osteotomy at one of 11 centers and were entered into a collaborative multicenter database. Of those, 34 (87%) were available for followup at a mean of 2.5 years (range 1-5 years). This group was compared with a matched group of 78 subjects, of whom 71 (91%) were available for followup at a similar interval. We compared clinical outcomes including UCLA activity score, SF-12, and Hip Disability and Osteoarthritis Outcome Score (HOOS); radiographic measures-anterior and lateral center-edge angle and acetabular inclination (AI)-and reoperations, major complications, and conversions to total hip arthroplasty. RESULTS: Although both groups reached clinical improvement in all categorical measures, the revision PAO group demonstrated greater pain (HOOS pain, study 74 versus 85, p = 0.03; 95% confidence interval [CI], 18.58 to -0.95) and less function (HOOS activities of daily living, study 80 versus 92, p = 0.002; 95% CI, 018.99-4.45) than the primary cohort. The revision cohort achieved a smaller average radiographic correction than in patients undergoing PAO without prior pelvic surgery. The mean correction in AI was less dramatic when directly comparing the revision and comparison groups (-12° to -17°, p < 0.001, SD 2.3-8.5). Although there was no difference in severe complications requiring further surgery, there were two conversions to hip arthroplasty (p = 0.109; 95% CI, 0.004-2.042) in the study group. CONCLUSIONS: PAO performed after prior pelvic surgery is associated with improvements in pain, function, radiographic correction, and early complication rates, but the improvements observed at short-term followup were smaller and more variable than those seen in patients who had not undergone prior pelvic surgery. We recommend considering PAO for residual deformities after prior osteotomy to improve function and quality life but warning patients of potential ceiling effects with a second periacetabular surgery.

Surgical Treatment of Adolescent Acetabular Dysplasia With a Periacetabular Osteotomy: Does Obesity Increase the Risk of Complications?

BACKGROUND: The Bernese periacetabular osteotomy (PAO) is frequently used to treat symptomatic acetabular dysplasia in the adolescent age group. Despite encouraging results, factors predictive of the development of postoperative complications remain poorly understood. The purpose of this study was to investigate whether obesity is a risk factor for complications following PAO in adolescents. METHODS: A retrospective cohort study design was used to collect data from 3 different institutions. Children and adolescents (below 19 y of age) who underwent PAO and were followed for minimum of 12 months were included. Obesity was defined as a body mass index ≥95 percentile. The modified Clavien-Dindo classification was used to grade complications. A logistic regression analysis was used to identify factors related to the development of a complication that required treatment outside of routine postoperative care (complication grades II to V). Changes in radiographic parameters including Tönnis acetabular roof angle, anterior center-edge angle, and lateral center-edge angle among obese versus nonobese subjects were also evaluated. RESULTS: The mean age at surgery among the 84 adolescents included in the study was 16.5 years (range, 12 to 19 y). A total of 11% of the population was considered obese. Obesity (P=0.0047) was the only variable significantly associated with the development of a complication. After controlling for study site, the odds of an obese subject developing a complication were 10 [95% confidence interval (CI), 1.89-59.8] times the odds of a nonobese subject developing a complication. There was no difference in the magnitude of change in anterior center-edge angle (P=0.1251), lateral center-edge angle (P=0.9774), or Tönnis (P=0.5770) angular correction that was achieved among the obese versus nonobese subjects following surgery. CONCLUSIONS: The Bernese PAO allows for adequate radiographic correction of acetabular dysplasia among obese and nonobese adolescents. However, the hip preservation surgeon should be aware of the higher risk of complications among obese adolescents undergoing PAO for the treatment of symptomatic acetabular dysplasia. LEVEL OF EVIDENCE: Level III-retrospective study.

Screening for deep vein thrombosis after periacetabular osteotomy in adult patients: is it necessary?

BACKGROUND: The periacetabular osteotomy has become a common procedure for treating symptomatic acetabular dysplasia. Like other major hip procedures, there is concern regarding the risk of associated venous thromboembolic disease. Nevertheless, there is limited information regarding the need for screening, and optimal prophylactic measures have not been established. QUESTIONS/PURPOSES: We sought to determine the frequency of thromboembolic events (deep vein thrombosis [DVT] and symptomatic pulmonary embolism [PE]) associated with the periacetabular osteotomy in in patients receiving aspirin and mechanical compression prophylaxis. METHODS: We performed a retrospective review of 134 adult patients (149 hips) treated with the periacetabular osteotomy during an 8-year period. During this period, 136 (91%) of the hips treated with a periacetabular osteotomy were screened within 1 week for DVT, whereas 13 (9%) could not be evaluated for various reasons. The mean age of the patients at the time of surgery was 30 years (range, 18-60 years), and no patients were lost to followup during the 4 to 6 months after surgery. The same thromboembolic prophylactic regimen was used for all patients. This consisted of 325 mg aspirin twice a day and compression stockings for 6 weeks and lower extremity pneumatic compression devices while hospitalized. Screening bilateral lower extremity ultrasonography was performed within 1 week (mean, 4 days) of the procedure to detect asymptomatic DVTs. RESULTS: Of the 134 patients, two patients (two hips) with negative postoperative screening ultrasounds presented at 14 and 38 days postoperatively with clinical symptoms of DVT. Repeat ultrasound confirmed this diagnosis in both cases. There were no symptoms of PE. Screening venous ultrasonography did not identify any DVTs during the early postoperative period before discharge. These two patients were treated with 3 to 6 months of warfarin anticoagulation. Neither patient had persistent symptoms related to the DVT. CONCLUSIONS: These data indicate that the risk of symptomatic DVT associated with periacetabular osteotomy is low (1%) with use of aspirin and mechanical compression prophylaxis. Furthermore, routine postoperative screening did not detect any patients with an asymptomatic DVT. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Acute compartment syndrome after intramedullary nailing of isolated radius and ulna fractures in children.

BACKGROUND: There exist varying reports in the literature regarding the incidence of compartment syndrome (CS) after intramedullary (IM) fixation of pediatric forearm fractures. A retrospective review of the experience with this treatment modality at our institution was performed to elucidate the rate of postoperative CS and identify risk factors for developing this complication. METHODS: In this retrospective case series, we reviewed the charts of all patients treated operatively for isolated radius and ulnar shaft fractures from 2000 to 2009 at our institution and identified 113 patients who underwent IM fixation of both-bone forearm fractures. There were 74 closed fractures and 39 open fractures including 31 grade I fractures, 7 grade II fractures, and 1 grade IIIA fracture. If the IM nail could not be passed easily across the fracture site, a small open approach was used to aid reduction. RESULTS: CS occurred in 3 of 113 patients (2.7%). CS occurred in 3 of 39 (7.7%) of the open fractures compared with none of 74 closed fractures (P=0.039), including 45 closed fractures that were treated within 24 hours of injury. An open reduction was performed in all of the open fractures and 38 (51.4%) of the closed fractures. Increased operative time was associated with developing CS postoperatively (168 vs. 77 min, P<0.001). CS occurred within the first 24 postoperative hours in all 3 cases. CONCLUSION: CS was an uncommon complication after IM fixation of pediatric diaphyseal forearm fractures in this retrospective case series. Open fractures and longer operative times were associated with developing CS after surgery. None of 45 patients who underwent IM nailing of closed fractures within 24 hours of injury developed CS; however, 51.4% of these patients required a small open approach to aid reduction and nail passage. We believe that utilizing a small open approach for reduction of one or both bones, thereby avoiding the soft-tissue trauma of multiple attempts to reduce the fracture and pass the nail, leads to decreased soft-tissue trauma and a lower rate of CS. We recommend a low threshold for converting to open reduction in cases where closed reduction is difficult.

Legg-Calvé-Perthes disease and slipped capital femoral epiphysis: major developmental causes of femoroacetabular impingement.

Problematic femoroacetabular impingement frequently is seen following Legg-Calvé-Perthes disease (LCPD) in young children and following slipped capital femoral epiphysis (SCFE) in older children and adolescents. Although symptoms may be mild in adolescents and young adults, chondral damage following LCPD and SCFE deformity is cumulative and irreversible, which has led to a recent emphasis on the consideration of early treatment. The surgical dislocation approach and improved MRI and three-dimensional CT have revealed common patterns of deformity and structural damage. The surgical dislocation approach is a superb diagnostic tool unmatched in assessing complex dynamic impingement patterns, and it allows direct treatment of deformity through recontouring of the head and neck and, in unhealed SCFE, epiphyseal realignment. The contemporary hip-preserving management of deformity following LCPD and SCFE is changing rapidly, necessitating careful evaluation of new treatment methods.

Management of Legg-Calvé-Perthes disease using an A-frame orthosis and hip range of motion: a 25-year experience.

BACKGROUND: Containment treatment is widely accepted in the management of Legg-Calvé-Perthes disease. Many reports indicate the need to regain hip motion before pelvic or femoral osteotomy, but have not indicated how osteotomy affected motion. Recent studies have suggested that osteotomy treatment of lateral pillar B hips may result in a higher proportion of spherical hips than those managed nonoperatively; however, outcomes for children older than 8 years of age or with pillar C involvement remain unsatisfactory. METHODS: The records of all patients with a diagnosis of Legg-Calvé-Perthes disease seen at our facility from 1985 through 2001 were reviewed. Two hundred and thirteen patients (175 males, 38 females), average age 6.4 years (range, 2.6 to 11.3 y), with 240 involved hips in the necrotic or the fragmentation stage were managed under a protocol to restore and maintain satisfactory hip abduction with an adductor tenotomy and abduction cast, followed by daily hip range-of-motion exercises and an A-frame orthosis to facilitate the concentric position of the epiphysis within the acetabulum. Assessment included measurement of hip abduction, femoral head sphericity and congruence, presence of femoral neck deformity, limb-length inequality, and later reconstructive surgical procedures. Hips were grouped by lateral pillar class (12A, 113B, 115C) and evaluated at maturity using a modified Stulberg grade. RESULTS: All pillar A hips were spherically congruent. Of pillar B hips, 101 were spherically congruent, 8 were aspherical but congruent, and 4 were aspherical and incongruent. Of pillar C hips, 77 were spherically congruent, 26 were aspherical but congruent, and 12 were aspherical and incongruent. Age did not correlate with outcome. Hip abduction improved and was maintained in all groups. CONCLUSIONS: Treatment that restored and maintained hip range of motion along with the use of an A-frame orthosis resulted in a high proportion of spherically congruent hips for patients of all ages irrespective of the extent of disease. Seventy-eight percent of pillar B and C hips were spherically congruent hips at maturity; overall, 93% of hips were congruent. This regimen has supplanted all other methods of treatment at our institution. LEVEL OF EVIDENCE: Level IV-case series.

A treatment algorithm for stable slipped capital femoral epiphysis deformity.

The authors' current experience in the surgical treatment strategy of stable slipped capital femoral epiphysis deformities was reviewed. From this, a treatment algorithm was developed that could be utilized as a guide in the evaluation and treatment of future patients with slipped capital femoral epiphysis. The clinical parameters of patients' histories of symptoms, physical examinations, and radiographic assessments of slip severity were used in formulating the algorithm. The intent was to prepare a comprehensive algorithm providing necessary alternate treatment pathways for the variable slip deformity in accordance with the surgical experience/expertise of the treating surgeon.

Femoral lengthening over a pediatric femoral nail: results and complications.

BACKGROUND: Limb lengthening by callotasis as described by Ilizarov has become the standard method of lower extremity lengthening. Lengthening over an intramedullary nail to allow early removal of the external fixator has also become common in adults but few studies have addressed the efficacy in children. METHODS: A retrospective review of 37 consecutive children who had undergone femoral lengthening with external fixator over an intramedullary nail was performed. Charts were reviewed for demographics, surgical details, and complications. Radiographs were examined to determine magnitude of lengthening and to calculate lengthening index. RESULTS: The average age of the 37 patients was 11.6 years (range, 8.1 to 17.0). The amount of lengthening averaged 7.0 cm (range, 3.0 to 11.4 cm), which represented a mean 20.4% increase in length. The mean time in the fixator was 81 days. The lengthening index was 1.21 days/mm. Thirteen patients developed major complications (37.8%) including 4 limbs that failed to lengthen initially, 3 fractures (1 before fixator removal and 3 after fixator removal), 2 nail failures, 4 deep infections, and 2 joint subluxations requiring operative care. The 3 fractures after fixator removal were treated with exchange nailing as were the 2 intramedullary nail failures. Four patients (10.8%) developed deep infections requiring irrigation, debridement, and IV antibiotics. One patient developed a late hip subluxation, which was treated with a shelf osteotomy but resulted in pain and limitation of motion. One patient developed knee subluxation during lengthening requiring operative intervention. The technique was successful in obtaining a good result with a functional lengthened femur without unresolved problems in 94% of the patients despite a significant rate of major complications, particularly in those with a congenital etiology. Only 2 of the 37 patients ultimately had results that were ultimately compromised by complications. CONCLUSIONS: Femoral lengthening over an intramedullary nail with the aid of an external fixator has shown to be an effective method for correcting limb length discrepancy. The technique has a high complication rate similar to other methods of lengthening. LEVEL OF EVIDENCE: Level IV-Case Series.

Team Approach: Hip Preservation Surgery.

The evaluation and treatment of adolescents and young adults with hip pain has seen tremendous growth over the past 20 years. Labral tears are well established as a common cause of hip pain but often occur because of underlying bony abnormalities. Femoroacetabular impingement (FAI) and acetabular dysplasia are now well-established causes of hip osteoarthritis and are increasingly treated in the prearthritic stage in hopes of improving symptoms and prolonging the longevity of the native hip. Beyond FAI and acetabular dysplasia, this patient population can present with a complex and variable group of underlying conditions that need to be taken into account. Expertise in the conservative management of this population, including physical therapy, is valuable to maximize the success. Preoperative, surgical, and postoperative decision-making and care in this population is complex and evolving. A comprehensive, multidisciplinary approach to the care of this patient population has been used for over 20 years by our institution with great success. The purpose of this article is to review the "team-based approach" necessary for successful management of the spectrum of adolescent and young adult hip disorders.

What are the factors associated with acetabular correction in Perthes-like hip deformities?

BACKGROUND: Perthes-like hip deformities encompass variable proximal femoral abnormalities and associated acetabular dysplasia that can be reconstructed with contemporary hip preservation procedures. Nevertheless, the necessity and indications for surgical correction of associated acetabular dysplasia have not been established. QUESTIONS/PURPOSES: We determined whether patient-specific factors (sex, age, BMI, previous surgery, hip pain and function) and/or structural deformity characteristics (radiographic parameters of acetabular morphology) were associated with our indications for acetabular reorientation in surgical reconstruction of Perthes-like hip deformities. METHODS: We compared patient-specific characteristics and radiographic parameters of acetabular morphology in 94 patients (97 hips) with residual Perthes deformities who underwent joint preservation surgery without or with a periacetabular osteotomy (PAO) as part of the reconstruction. RESULTS: Patient sex, BMI, preoperative Harris hip score, and previous hip surgery were not associated with our indications for a combined femoral and PAO procedure. Radiographic parameters associated with the indication for a PAO included the lateral center-edge angle, anterior center-edge angle, acetabular inclination, and acetabulum-head index. No or mild secondary osteoarthritis and joint congruency were associated with the indication for a PAO as part of the reconstruction. CONCLUSIONS: Contemporary hip preservation surgery for residual Perthes deformities covers a wide spectrum of procedures. We believe a PAO should be considered in the surgical treatment plan for symptomatic patients having radiographic parameters indicating acetabular dysplasia, no or mild secondary osteoarthritis, and adequate joint congruity. LEVEL OF EVIDENCE: Level III, prognostic study. See Instructions for Authors for a complete description of levels of evidence.