Faculty Bibliography

BACKGROUND:Retroversion of the acetabulum is a cause of pincer impingement. Symptomatic retroversion has traditionally been treated with anteverting periacetabular osteotomy (PAO). However, arthroscopic rim trimming can also treat pincer impingement associated with acetabular retroversion. The purpose of this study was to report the outcomes and radiographic findings in a series of adolescent patients with symptomatic acetabular retroversion treated arthroscopically. METHODS:Data were prospectively gathered at a single institution using an established hip preservation registry. Patients below 18 years with a retroverted acetabulum that underwent primary hip arthroscopy with 2-year follow-up were included. Acetabular retroversion was defined by 3 radiographic criteria: the presence of crossover, ischial spine sign, and posterior wall sign. Radiographic measurements of the lateral center-edge angle, anterior center-edge angle, alpha angle, and crossover percentage were reported preoperatively and postoperatively. Patient-reported outcome (PROs) measures included the modified Harris Hip Score, the non-Arthritic Hip Score, Hip Outcome Score Sports Subscale, visual analog scale, and patient satisfaction, recorded at 3 months, 1 year, and 2 years, postoperatively. In addition, International Hip Outcome Tool scores were gathered at 2 years. RESULTS:Between April 2008 and July 2014, there were 43 patients (48 hips) treated with hip arthroscopy who met the inclusion criteria. The average age was 16.1 years (range, 13.9 to 17.9 y) and there were 38 females and 10 males. The average follow-up was 50.4 months, with a minimum of 2 years. Statistically significant improvements in all PROs were found at 2 years postoperatively. There were 9 hips with lateral center-edge angle ≤25 degrees; the PROs of this group was not different than patients with normal coverage. Three patients underwent arthroscopic revision. No patient subsequently underwent anteverting PAO during the study period. There were no reported complications. CONCLUSIONS:Femoroacetabular impingement caused by acetabular retroversion treated with hip arthroscopy demonstrates good outcomes at 2 years with a low complication rate. Symptomatic adolescents may be safely and successfully treated arthroscopically, potentially avoiding anteverting PAO. STUDY DESIGN/METHODS:Level of evidence 4-case series.

The Ponseti method for the correction of idiopathic talipes equinovarus (ITEV) produces excellent results, however recurrence is common, ranging from 11-37%. Recurrences require repeat manipulation and casting, frequently followed by surgical procedures. We hypothesized that at a minimum 4-year follow-up, the rate of invasive surgical interventions such as posteromedial release (PMR) or osteotomy, is low. A retrospective chart review of patients with ITEV treated by the Ponseti method from January 1999 to June 2017 was conducted. An invasive procedure was defined as a PMR or osteotomy, whereas minimally invasive procedures involved tendon lengthening and transfers. Inclusion criteria were patients with ITEV, less than 90 days old at initial visit, no previous series of casts, and potential of being 4 years old at last visit. A total of 150 feet (102 patients) were studied. Mean age at initial visit and last follow-up were 19.5 days and 7.6 years, respectively. For the initial series of casts, mean number of casts was 5.4 and 67.3% of feet had percutaneous Achilles tenotomies. Fifty-eight percent did not undergo any form of surgical procedure, while 33% underwent a tibialis anterior tendon transfer alone or in combination with a gastrocnemius recession, tendo-Achilles lengthening, or plantar fascia release. Early in the series, three feet in two patients underwent a PMR. The mean age at time of surgery was 55.3 months. In contrast to those treated for recurrence after PMR, the vast majority (98%) of feet with recurrence after Ponseti-treated ITEV had either no surgery or minimally invasive surgery

The Patient-Reported Outcomes Measurement Information System (PROMIS) was developed to examine the quality of life across various medical conditions. No studies have evaluated the use of the PROMIS in children with idiopathic talipes equinovarus (ITEV). The construct validity of the PROMIS Parent Proxy Profile short forms version was assessed by comparing its domains of Mobility, Fatigue and Pain Interference to the Function domain of the Disease Specific Instrument (DSI) for ITEV. The two questionnaires were mailed out to the parents of 93 patients, aged 5-17 years, with ITEV. We received a total of 21 complete responses (22.6% response rate). The patients' current mean age was 8.0 years (SD, 3.0 years). Seventeen were males and 4 were females. Nine had unilateral ITEV and 12 had bilateral ITEV. Bivariate correlation analysis, using Pearson correlation coefficients, demonstrated a moderate positive correlation between the DSI Function domain and the PROMIS Mobility domain (r=0.67) as well as a moderate negative correlation between the DSI Function domain and the PROMIS Pain Interference domain (r=-0.64). A fair negative correlation was found between the DSI Function domain and the PROMIS Fatigue domain (r=-0.35). These results provide support for the validity of the PROMIS Mobility Item in this population, however further studies are needed to assess the feasibility and reliability of these instrument items as well as other items within PROMIS

BACKGROUND:Idiopathic talipes equinovarus (ITEV) is a prevalent structural deformity of the foot and ankle in children. The disease-specific instrument (DSI) has commonly been used as an outcomes metric in these patients. The Patient-Reported Outcomes Measurement Information System (PROMIS) was developed to examine the quality of life across various medical conditions. PROMIS has been validated for multiple conditions; however, no studies have evaluated the use of the PROMIS in children with ITEV. METHODS:A prospective analysis was performed whereby the 2 questionnaires were mailed out to the parents of 91 patients, aged 5 to 17 years, with ITEV. Construct validity of the PROMIS Parent Proxy Profile short forms version was assessed by comparing its domains of Mobility, Fatigue, Pain Interference, and Pain Intensity to the DSI Function domain and PROMIS domains of Anxiety, Depressive Symptoms, Peer Relationships, and Pain Intensity to DSI Satisfaction domain. RESULTS:Thirty-one complete responses (34% response rate) were returned. The patients' current mean age was 8.8 years, 7 were female individuals, and 12 had unilateral ITEV. Bivariate correlation analysis, using Spearman correlation coefficients, demonstrated a moderate positive correlation between the DSI Function domain and the PROMIS Mobility domain (rs=0.52) and a moderate negative correlation between the DSI Function domain and the PROMIS Pain Interference domain (rs=-0.56), as well as the PROMIS Pain Intensity domain (rs=-0.75). A fair negative correlation (rs=-0.38) with PROMIS Fatigue domain was found. Correlations between the DSI Satisfaction domain and the PROMIS domains were fair or had little relationship. CONCLUSIONS:These results provide support for the validity of the PROMIS Mobility, Pain Interference, and Pain Intensity domains in this population, however there are no items in PROMIS that can assess overall satisfaction, as with the DSI. LEVEL OF EVIDENCE/METHODS:Level II-prospective comparative study.

Congenital tibial deficiency is a rare condition characterized by partial to complete absence of the tibia, an intact but frequently overgrown fibula, variable degrees of knee deformity and function, and an abnormal equinovarus foot. It can occur in isolation but also presents concurrently with other orthopaedic anomalies and syndromic conditions. Among these, congenital abnormalities of the hand and femur are most commonly observed. Many theories exist regarding its etiology and some genetic mutations have been identified; however, the underlying mechanism remains unknown. The prognosis and treatment differ based on the clinical severity. The goal of treatment is always to create a stable, functional limb, most commonly with amputation and use of prosthetics. Controversy exists over the level of amputation and the usefulness of reconstructive procedures to preserve the foot and limb length. Current investigation on this complex disorder is focused on identifying its origins and further developing a classification-based treatment algorithm to improve patient outcomes.

BACKGROUND:Hip arthroscopy is an established surgical treatment for pathologic hip conditions in athletes. There is a paucity in the literature regarding outcomes and return to sport for athletes in the midterm. PURPOSE:To report minimum 5-year outcomes, return to sport, and level of sport among athletic patients who underwent hip arthroscopy. In addition, we compared 2- and 5-year outcomes to evaluate whether there is a deterioration in functional status. STUDY DESIGN:Case series; Level of evidence, 4. METHODS:Data were prospectively collected on all patients who underwent hip arthroscopy between February 2009 and November 2011 at 1 institution. Athletes at the high school, collegiate, or professional level who underwent hip arthroscopy and had preoperative patient-reported outcome (PRO) scores were considered for inclusion. Exclusion criteria were preoperative Tönnis grade >1 or prior ipsilateral hip conditions or surgery. Data on sports participation, competition level, and ability were collected. At a minimum of 5 years postoperatively, PROs, visual analog scale (VAS), iHOT-12 (short version of International Hip Outcome Tool), satisfaction, and postoperative complication data were collected. RESULTS:Seventy-seven hips met all criteria, among which 66 (85.7%) had a minimum 5-year follow-up and were included. There were 37 high school, 20 collegiate, and 9 professional athletes. Mean ± SD improvements at a minimum of 5 years were as follows: modified Harris Hip Score, 66.8 ± 16.3 to 87.0 ± 14.8 ( P < .001); nonarthritic hip score, 66.2 ± 19.9 to 87.2 ± 15.2 ( P < .001); Hip Outcome Score-Sports Specific Subscale, 47.0 ± 22.4 to 79.1 ± 23.0 ( P < .001); and VAS, 5.4 ± 2.5 to 1.8 ± 2.1 ( P < .001). At latest follow-up, mean iHOT-12 was 78.8 ± 22.7, and satisfaction was 8.2. A total of 50 athletes (53 hips, 80.3%) reported that they returned to sports; 71.2% reported "same" or "higher" sport ability as compared with a year before surgery. Postoperative complications included 3 cases (4.5%) of numbness and 1 case (1.5%) of pulmonary embolism. Ten hips (15.2%) required secondary arthroscopies, and no hips were converted to total hip arthroplasty. There were no significant differences between 2- and 5-year PROs, VAS, or satisfaction. CONCLUSION:Midterm results of hip arthroscopy in athletes are shown to be safe and favorable. Most athletes return to sports and continue to play after 5 years with the same or higher ability.

Femoral version is reported to vary in relation to age, gender and other patient-specific factors. Differences in femoral version are suspected to contribute to the development of hip pathology. However, normative data on pathologic hips has never been reported. To evaluate the femoral version in a large population of patients with symptomatic hip pathology treated with arthroscopy and report differences within this group based on age, gender, bony morphology and other hip-related factors. A prospectively gathered database of 1449 hips was reviewed. All patients underwent pre-operative MRI with measure of femoral version. The average femoral version of the entire population was 8.4+ 9.2°, range -23 to 63. There no statistically significant differences encountered based on age, gender, bony morphology or other hip-related factors. Across all groups, there was wide variation in the femoral version present. Among younger patients, there was trend to have a greater proportion of retroversion. Significant variation in femoral version exists in patients with symptomatic hip pathology. Although the geometry of the proximal femur is commonly described as anteverted, relative retroversion is also frequently encountered.

INTRODUCTION/BACKGROUND:There is a paucity in the literature regarding mid-term results of microfracture in hip arthroscopy. We aim to assess 5-year outcomes of patients who underwent acetabular microfracture for full-thickness chondral lesions as a part of hip arthroscopy. METHODS:Between August 2008 and September 2011, data were prospectively gathered for patients undergoing acetabular microfracture during hip arthroscopy with minimum 5-year follow-up. All patients were assessed pre- and postoperatively, with modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), Hip Outcome Score - Sports Specific Subscale (HOS-SSS), and visual analog scale (VAS). International Hip Outcome Tool (iHOT-12) and satisfaction were collected postoperatively. Exclusion criteria included previous hip conditions, or preoperative Tönnis grade ≥2. RESULTS:Fifty three hips were eligible for this study. Of these, 43 (81.1%) hips in 42 patients had follow-up. The study group had a male majority (65.1%) and an average age of 44.4 ± 9.5 years. There was statistically significant improvement in all patient-reported outcomes (PROs) and VAS at follow-up. Patient satisfaction was 7.6 ± 2.6. A comparison of 2-year to minimum 5-year follow-up results identified no statistically significant deterioration in PROs, VAS, and patient satisfaction. Survivorship was 72.1% with 12 patients converted to total hip arthroplasty (THA). Four patients (10.8%) underwent secondary arthroscopy. CONCLUSIONS:In the mid-term, microfracture as a part of hip arthroscopy demonstrated favourable outcomes and 72% survivorship. Careful patient selection is warranted to limit the risk of conversion to THA.

Radiographic Union Score for Tibia (RUST) and modified RUST (mRUST) are radiographic tools for quantitatively evaluating fracture healing using a cortical scoring system. This tool has high intra-class correlation coefficients (ICCs); however, little evidence has evaluated the scores against the physical properties of bone healing. Closed, stabilized fractures were made in the femora of C3H/HeJ male mice (8-12 week-old) of two dietary groups: A control and a phosphate restricted diet group. Micro-computed tomography (µCT) and torsion testing were carried out at post-operative days (POD) 14, 21, 35, and 42 (n = 10-16) per group time-point. Anteroposterior and lateral radiographic views were constructed from the µCT scans and scored by five raters. The raters also indicated if the fracture were healed. ICCs were 0.71 (mRUST) and 0.63 (RUST). Both RUST scores were positively correlated with callus bone mineral density (BMD) (r = 0.85 and 0.80, p < 0.001) and bone volume fraction (BV/TV) (r = 0.86 and 0.80, p < 0.001). Both RUST scores positively correlated with callus strength (r = 0.35 and 0.26, p < 0.012) and rigidity (r = 0.50 and 0.39, p < 0.001). Radiographically healed calluses had a mRUST ≥13 and a RUST ≥10 and had excellent relationship to structural and biomechanical metrics. Effect of delayed healing due to phosphate dietary restrictions was found at later time points with all mechanical properties (p < 0.011), however no differences found in the RUST scores (p > 0.318). Clinical relevance of this study is both RUST scores showed high correlation to physical properties of healing and generally distinguished healed vs. non-healed fractures. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:945-953, 2018.

Arthroscopic acetabuloplasty involves trimming of bone from the acetabular rim. Although early techniques often involved detachment of the labrum prior to bone resection, recent studies have reported on acetabuloplasty without labral detachment. This method has the benefit of preserving the labro-osseous junction, but visualization of the acetabular rim may be more difficult. Compromised visualization can lead to incomplete resection and residual impingement. We describe an arthroscopic perspective called the "bird's eye" and "upper deck" views that facilitates optimal visualization of the acetabuloplasty without labral detachment.