Yen, Yi‐Meng

Abstract Background Femoral version plays a critical role in pre-arthritic hip pain, particularly in femoroacetabular impingement (FAI). Variations in femoral version may contribute to hip instability or impingement. This study examines the outcomes of hip arthroscopy for FAI across different femoral version groups. Methods A prospective multicenter cohort of 677 FAI patients undergoing primary hip arthroscopy was collected, with 603 patients in this study based on recorded femoral version. Inclusion criteria were patients aged 14-45 years with idiopathic FAI, while previous ipsilateral hip procedures, associated disorders, or Tönnis 2 or greater osteoarthritis were excluded. Femoral version was measured on low-dose computed tomography (CT) utilizing the Yoshioka oblique method and categorized into five subgroups: <5°, 6°-15°, 16°-25°, 26°-35°, 35°+. Patient-reported outcomes (PROs) were obtained at minimum one-year follow-up. The modified Harris hip score (mHHS) was assessed relative to minimal clinically important difference (MCID) of 8 and patient acceptable symptom state (PASS) of 74. Additional PROs included HOOS Pain and Sports/Recreation subscores and iHOT-12 score. Composite failure was defined as reoperation for persistent symptoms or failure to achieve either the mHHS MCID or PASS. Results Males had statistically lower femoral version than females (14.0 vs 18.0; p<0.001). In females, 38.0% had a femoral version of 16°-25°, 17.9% between 26°-35°, and 3.6% greater than 35°, compared to 27.6%, 9.2%, and 1.8% in males, respectively (all p<0.001). Increased or decreased femoral versions appear to have similar outcomes to normal version. The mildly increased femoral anteversion groups of 16°-25° and 26°-35° demonstrated the best outcomes with changes in HOOS pain and sports subscores being significantly higher. Severely increased femoral anteversion, >35°, only present in 2.8% of patients, demonstrated a higher composite failure rate (15.4%) compared to moderately increased, 26°-35°, femoral version (3.1%). The decreased femoral version group, ≤5°, had a composite failure of 10.4% compared to normal femoral version, 16°-25° (10.2%). Conclusions The general anatomy differences between males and females lends males to be more in retroversion while females tend to be more anteverted. Overall, outcomes did not seem to differ between increased or decreased femoral versions but were superior at mildly increased femoral versions.

Objectives: The role of femoral version (FV[MOU1] ) in the pre-arthritic hip pain remains increasingly recognized, including in femoroacetabular impingement (FAI). Increased femoral version or decreased femoral version may play a role in hip biomechanics contributing to hip instability or impingement, respectively. The purpose of this study was to compare the outcomes of hip arthroscopy for FAI across different femoral version groups in a multicenter prospective cohort study. Methods: A prospective multicenter cohort study of 677 FAI patients undergoing primary hip arthroscopy was performed. The current study included 603 patients with low-dose CT performed preoperatively for measurement of femoral version from the larger cohort. Inclusion criteria were patients aged 14-45 years with idiopathic FAI. Exclusion criteria were previous ipsilateral hip procedures, associated disorders, or Tönnis 2 or greater osteoarthritis. Femoral version was measured on low-dose computed tomography (CT) utilizing the Yoshioka oblique method and was broken into five subgroups: <5° (decreased FV), 6-15° (normal FV), 16-25° (mildly increased FV), 26-35° (moderately increased FV), 35°+ (severely increased FV). Patient-reported outcomes (PROs) were measured at a minimum one-year follow-up. The modified Harris hip score (mHHS) was assessed relative to the minimal clinically important difference (MCID) of 8 and patient acceptable symptom state (PASS) of 74. Additional PROs included the HOOS Pain and Sports/Recreation subscores and the iHOT-12 score. Composite failure was defined as a reoperation for persistent symptoms or a failure to achieve either the mHHS MCID or PASS. Independent t-test (Mann-Whitney U) and ANOVA were utilized to compare groups. Results: Males had statistically lower femoral version than females (14.0° vs 18.0°; p<0.001). In females, 38.0% had mildly increased FV, 17.9% had moderately increased FV, and 3.6% had severely elevated FV. This is compared to 27.6%, 9.2%, and 1.8% in males, respectively (all p<0.001). Decreased FV was present in 7.1% of males, compared to 5.9% of females. Increased or decreased femoral versions appear to have similar outcomes to normal version when evaluated by PROs or outcome states. In fact, mildly increased and moderate increased FV group demonstrated the best outcomes. Changes in HOOS pain and sports subscores were significantly higher for these groups. Severely increased FV, >35°, was only present in 2.8% of patients but did demonstrate a higher rate of composite failure (15.4%) compared to moderately increased FV (3.1%). The decreased FV group had a composite failure of 10.4% compared to normal femoral version, 16-25° (10.2%). Conclusions: In a patient cohort undergoing hip arthroscopy for FAI, significant differences in FV between males and females were present. Overall, in a multicenter prospective cohort study, the outcomes of hip arthroscopy for FAI did not seem to differ between increased or decreased femoral versions but were superior in mild to moderately increased FV. Future research with longer-term follow-up is still needed to definitively establish the longevity of outcomes of hip arthroscopy relative to FV.

Abstract Introduction: Low-dose computed tomography (CT) has been increasingly utilized in FAI due to its improved ability to characterize the complex and variable hip morphologies of FAI patients, compared to plain radiographs. This study defined FAI morphology between females and males as well as across adolescents, young adults, and older adults. Methods: A multi-center, prospective cohort of FAI patients undergoing primary arthroscopy was performed. Patients 14-45 years of age with idiopathic FAI were included. Low-dose CT was used for preoperative planning. Analysis focused on acetabular and femoral morphology and the differences between females/males and adolescents (A,14-18.9)/young adults (Y,19-24.9)/older adults (O,25+). Adolescents were the reference group during analysis. Results: There were 604 patients with CT data. Mean age was 24.9 years with 55.9% female. Males had more anterosuperior coverage (i.e. 64.2% vs 62.5% at 1:00), lower version (14.1° vs 18.0°), smaller femoral neck-shaft angles (130.9° vs 133.4°), and larger alpha angles (i.e. 72.1° vs 58.6° at 1:00) compared to females. Multivariable analysis demonstrated that females had associations with more femoral anteversion (OR: 1.05,CI: 1.03-1.07) and larger femoral neck-shaft angles (OR: 1.11,CI: 1.06-1.16). Males has associations with larger alpha angles at 1:00 (OR: 1.05,CI: 1.02-1.07) and 1:30 (OR: 1.03,CI: 1.00-1.06) as well as radial coverage at 1:00 (OR: 1.18,CI: 1.11-1.26). For females, adolescents had slightly less radial coverage at 2:00 (49.9%) compared to young (51.2%) and older adults (51.4%). Femoral neck-shaft angle decreased across age groups (A: 134.4°,Y: 133.0°,O: 132.7°). Alpha angles increased at 2:00 with age (A:54.6°,Y:55.3°,O:58.7°). Multivariable analysis had femoral neck-shaft angle decreasing for young (OR: 0.932,CI: 0.87) and older adults (OR:0.92,CI: 0.86-0.98) and it also had alpha angle at 1:15 increasing for young adults (OR: 1.03,CI: 1.00-1.06) and older adults (OR: 1.03,CI: 1.01-1.06). Males did not have any appreciable differences alpha angles, femoral version, or acetabular coverage across age groups. Conclusion: Differences in morphology identified on CT exist between females and males as well as across age groups for females. These differences may offer insight into disease pathomechanics between these patient populations. Further studies should confirm these findings and look at how they affect patient outcomes after treatment.

Objectives: Femoroacetabular impingement (FAI) is classically described as restricted internal rotation in flexion resulting in labral and cartilage pathology. Despite 20 years of FAI research, there is still limited understanding of the drivers of symptomatology in the subset of patients with underlying FAI morphology. While the prevalence of FAI morphologies is substantially higher in men, numerous studies have shown more women being treated for FAI compared to men. Soft-tissue laxity and hip instability are increasingly recognized as a potential contributor to symptoms in addition to FAI. The Beighton score is a well-accepted means to quantify soft-tissue laxity and has been validated for self-scoring. The purpose of the current study was to (1) investigate the prevalence of soft-tissue laxity in male and female patients presenting with symptomatic FAI in a multicenter prospective cohort study, and (2) correlate soft-tissue laxity with patient primary complaints of either mobility, stability, or pain. Methods: A prospective multicenter cohort study of 696 FAI patients undergoing primary hip arthroscopy surgery was performed and utilized for the current study. Inclusion criteria are patients aged 14 to 45 years old with idiopathic FAI not caused by childhood disease. Exclusion criteria are previous ipsilateral hip procedures or disease processes such as neuromuscular disease or Tonnis 2 or greater osteoarthritis. The Beighton score was assessed by electronic patient self-scoring. Beighton scores >4 were considered a marker of soft-tissue laxity. The MSP index was utilized to have patients rank from most to least the biggest problems with their hip: Mobility (M), Stability (S), or Pain (P). The chi-square or Fisher exact test were utilized to compare groups. Results: The prevalence of Beighton scores >4 was 57.2% in female patients, compared to 29.3% in male patients (p < 0.001). In female patients, 44.4%, 22.6%, and 7.7% had Beighton scores of 5+, 7+, and 9 respectively, compared to 16.7%, 5.8%, and 1.8% in male patients (all p < 0.005). In the overall FAI cohort, pain was the primary complaint in 72.1% of patients, compared to 24.2% complaining primarily of mobility and 3.7% complaining primarily of stability. Among female patients, the presence of soft-tissue laxity (relative to thresholds of Beighton 4, 5, 7, and 9) did not significantly influence the patient primary complaints (with pain being the predominant complaint). Overall, 85 female patients had a Beighton score of 7 or greater and only 2.4% reported stability of the hip as a primary complaint, compared to 2.4% of female patients with a Beighton <7. Stability was more commonly indicated as a second most important factor in the setting of soft-tissue laxity, compared to mobility. Among female patients with a Beighton >7, 29.5% reported stability as a primary or secondary complaint, compared to 15.2% of female patients with a Beighton score <7. Conclusions: Over half of female patients undergoing FAI surgery have underlying soft-tissue laxity as measured by the Beighton score. In the setting of soft-tissue laxity, patient primary symptomatic complaint remains pain, but a secondary complaint is significant more likely to be stability rather than mobility (compared to FAI patients without soft tissue laxity complain of mobility secondarily over stability). Further research is needed to better understand the role of soft-tissue laxity in the pathophysiology of FAI and the outcomes of surgical treatment.

Background/Objective: To share technical pearls of a basic knee arthroscopy in a pediatric patient by presenting tips and tricks used by experienced pediatric arthroscopists. Indications: Knee arthroscopy is a common procedure performed by most orthopedic surgeons. However, technical considerations and equipment should be considered before performing this procedure in a pediatric patient. This video provides information on indications, equipment, and patient positioning, as well as outlining a systematic approach to diagnostic arthroscopy and pertinent pediatric anatomy. Discussion/Conclusion: This video provides an excellent overview as well as specific pathology-dependent considerations for the inexperienced orthopedic surgeon, or the orthopedic surgeon who rarely performs knee arthroscopy. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Background: Tibial spine fractures (TSFs) are uncommon injuries that may result in substantial morbidity in children. A variety of open and arthroscopic techniques are used to treat these fractures, but no single standardized operative method has been identified. Purpose: To systematically review the literature on pediatric TSFs to determine the current treatment approaches, outcomes, and complications. Study Design: Meta-analysis; Level of evidence, 4. Methods: A systematic review of the literature was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) guidelines using PubMed, Embase, and Cochrane databases. Studies evaluating treatment and outcomes of patients <18 years old were included. Patient demographic characteristics, fracture characteristics, treatments, and outcomes were abstracted. Descriptive statistics were used to summarize categorical and quantitative variables, and a meta-analytic technique was used to compare observational studies with sufficient data. Results: A total of 47 studies were included, totaling 1922 TSFs in patients (66.4% male) with a mean age of 12 years (range, 3-18 years). The operative approach was open reduction and internal fixation in 291 cases and arthroscopic reduction and internal fixation in 1236 cases; screw fixation was used in 411 cases and suture fixation, in 586 cases. A total of 13 nonunions were reported, occurring most frequently in Meyers and McKeever type III fractures (n = 6) and in fractures that were treated nonoperatively (n = 10). Arthrofibrosis rates were reported in 33 studies (n = 1700), and arthrofibrosis was present in 190 patients (11.2%). Range of motion loss occurred significantly more frequently in patients with type III and IV fractures ( P < .001), and secondary anterior cruciate ligament (ACL) injury occurred most frequently in patients with type I and II fractures ( P = .008). No statistically significant differences were found with regard to rates of nonunion, arthrofibrosis, range of motion loss, laxity, or secondary ACL injury between fixation methods (screw vs suture). Conclusion: Despite variation in TSF treatment, good overall outcomes have been reported with low complication rates in both open and arthroscopic treatment and with both screw and suture fixation. Arthrofibrosis remains a concern after surgical treatment for TSF, but no significant difference in incidence was found between the analysis groups. Larger studies are necessary to compare outcomes and form a consensus on how to treat and manage patients with TSFs.

Background: Type I tibial spine fractures are non-displaced or minimally displaced (≤ 2mm displacement) fractures of the tibial eminence and ACL insertion traditionally managed nonoperatively with immobilization. Hypothesis/Purpose: We hypothesized that type I fractures do not carry significant risk of associated injuries and therefore do not require additional interventions aside from immobilization. Methods: We reviewed 52 patients classified by their treating institution with type I tibial spine fractures presenting between January 1, 2000 and January 31, 2019 at 10 institutions. Patients of age ≤ 18 years with pre-treatment plain radiographs and at least one year of follow-up were included. Data was collected on patient demographics, injury mechanism, treatment details, presence of concomitant injuries, range of motion (ROM) at final follow-up, treatment complications, and any return to the operating room for the injured knee. Pre-treatment imaging was reviewed by four authors to assess agreement of classification among the treating institutions. Patients were subclassified into two groups to ensure outcomes represented classic type I fracture patterns. Any patient with universal agreement among the four authors that the fracture did not appear consistent with a type I classification were assigned to Type 1+ Group (T1+). All other patients were assigned to the True Type I Group (TT1). We evaluated concomitant injury, need for operative intervention, and treatment outcomes overall and for each group independently. Results: 48 patients met inclusion criteria. 40/48 were TT1 fractures, while 8/48 were T1+ fractures, indicating less than universal agreement among sports specialists in classification of these fractures. Among TT1 patients, 7 of 40 (18.4%) underwent surgical treatment, though this represented 35.7% (5/14) of those who had undergone pretreatment advanced imaging. In the T1+ group, 6 of 8 (75%) underwent surgical treatment, 50% of whom (3/6) had pretreatment advanced imaging. Overall, twelve of 48 patients (25%) had concomitant injuries, nine TT1 patients and three T1+ patients (p=0.77), with 7 concomitant injuries requiring additional surgical management. Conclusions: Classification of type I fractures can be challenging. Nonetheless, a substantial percentage of patients with these fractures (>20%) were found to have concomitant injuries by advanced pretreatment imaging, with surgical management indicated in 58.3% of these patients. Contrary to traditional thought, type I tibial spine fractures do carry a risk of associated injuries. Simple cast immobilization may not be the ideal treatment in all cases. Advanced imaging would be beneficial for those whose plan of care may initially be non-operative treatment.

Background: When operative treatment is indicated, tibial spine fractures can be successfully managed with open or arthroscopic reduction and internal fixation. Hypothesis/Purpose: We hypothesized both approaches can lead to satisfactory outcomes for fracture healing, but that open treatment without preoperative advanced imaging can potentially lead to missed concomitant injuries. Methods: We performed an Institutional Review Board (IRB)-approved retrospective cohort study of pediatric tibial spine fractures presenting between January 1, 2000 and January 31, 2019 at 10 institutions. Patients were categorized into two cohorts based on treatment: arthroscopic reduction and internal fixation (ARIF) and open reduction and internal fixation (ORIF). Surgical outcomes, the incidence of concomitant injuries, and surgeon demographics were compared between groups. Results: There were 477 patients with tibial spine fractures who met inclusion criteria, 420 of whom (88.1%) were treated with ARIF, while 57 (11.9%) were treated with ORIF. Patients treated with ARIF were more likely to have an identified concomitant injury (41.4%) compared to those treated with ORIF (24.6%, p=0.021). Patients treated with ARIF were also more likely to have pre-treatment MRI (41.7% vs. 22.8%, p =0.010). Most concomitant injuries (74.5%) required surgical intervention. The most common treatment complications included arthrofibrosis (6.9% in ARIF patients, 7.0% in ORIF patients, p=1.00) and subsequent ACL injury (2.1% in ARIF patients and 3.5% in ORIF, p=0.86). The rate of complications, return to the operating room, and failure to return to full range of motion were similar between groups. Twenty surgeons with sports subspecialty training completed 85.0% of ARIF cases; the remaining 15.0% were performed by 12 surgeons without additional sports training. The majority (56.1%) of ORIF cases were completed by 14 surgeons without sports subspecialty training. Conclusion: This is the largest study comparing ARIF to ORIF in pediatric tibial spine fractures. This study demonstrated no difference in outcomes or nonunion following ARIF or ORIF for pediatric tibial spine fractures. There were significantly higher rates of concomitant injuries in patients treated with ARIF, however, these patients also had a higher rate of pre-treatment MRI. The majority of these concomitant injuries (74.5%) required surgical intervention. Pre-treatment MRI should be considered in the workup of tibial spine fractures to increase identification of concomitant injury. Concomitant injuries may be missed in tibial spine fractures treated with an open approach, especially in cases where preoperative advanced imaging is not obtained. Surgeon preference and training may impact treatment approach and identification and treatment of concomitant injury.

Background: When operative treatment is indicated, tibial spine fractures can be successfully managed with open or arthroscopic reduction and internal fixation (ARIF). The purpose of the study is to evaluate short-term treatment outcomes of tibial spine fractures in patients treated with both open and arthroscopic fracture reduction. Methods: We performed an Institutional Review Board (IRB)-approved retrospective cohort study of pediatric tibial spine fractures presenting between January 1, 2000 and January 31, 2019 at 10 institutions. Patients were categorized into 2 cohorts based on treatment: ARIF and open reduction and internal fixation (ORIF). Short-term surgical outcomes, the incidence of concomitant injuries, and surgeon demographics were compared between groups. Results: There were 477 patients with tibial spine fractures who met inclusion criteria, 420 of whom (88.1%) were treated with ARIF, while 57 (11.9%) were treated with ORIF. Average follow-up was 1.12 years. Patients treated with ARIF were more likely to have an identified concomitant injury (41.4%) compared with those treated with ORIF (24.6%, P=0.021). Most concomitant injuries (74.5%) were treated with intervention. The most common treatment complications included arthrofibrosis (6.9% in ARIF patients, 7.0% in ORIF patients, P=1.00) and subsequent anterior cruciate ligament injury (2.1% in ARIF patients and 3.5% in ORIF, P=0.86). The rate of short-term complications, return to the operating room, and failure to return to full range of motion were similar between treatment groups. Twenty surgeons with sports subspecialty training completed 85.0% of ARIF cases; the remaining 15.0% were performed by 12 surgeons without additional sports training. The majority (56.1%) of ORIF cases were completed by 14 surgeons without sports subspecialty training. Conclusion: This study demonstrated no difference in outcomes or nonunion following ARIF or ORIF, with a significantly higher rate of concomitant injuries identified in patients treated with ARIF. The majority of identified concomitant injuries were treated with surgical intervention. Extensive surgical evaluation or pretreatment magnetic resonance imaging should be considered in the workup of tibial spine fractures to increase concomitant injury identification. Level of Evidence: Level III.