Athletic Hip Injuries and Capsular Laxity

Associations Between Hip Pathology, Hip and Groin Pain, and Injuries in Hockey Athletes: A Clinical Commentary

Femoroacetabular impingement (FAI), particularly cam morphology, is highly prevalent among elite hockey athletes. Moreover, hip and groin pain has become a common issue in hockey, with approximately 50% of European professional athletes reported to experience a hip or groin problem during a season. While most athletes will not miss training or competition due to this, restricted competitive performance and increased risk of reduced physical and psychological well-being are likely. Recent research suggests that the development of cam morphology is related to the repetitive shear stresses experienced at the hip joint during adolescence from skating. This condition likely increases the potential for intra-articular and extra-articular injuries in these athletes later in their careers. Research also indicates that the hip joint mechanics during forward skating substantially increase the possibility of sustaining a labral tear compared to other sports. Such an injury can increase femoral head movement within the joint, potentially causing secondary damage to the iliofemoral ligament, ligamentum teres and joint capsule. These injuries and the high density of nociceptors in the affected structures may explain the high prevalence of hip and groin pain in hockey athletes. Compensatory adaptations, such as reduced hip strength, stability, and range-of-motion (ROM) likely increase the opportunity for core muscle injuries and hip flexor and adductor injuries. Specifically, the limited hip ROM associated with cam morphology appears to exacerbate the risk of these injuries as there will be an increase in pubic symphysis stress and transverse strain during rotational movements. It is hoped that this article will assist practitioners currently working with hockey athletes to develop evidence-informed monitoring strategies and training interventions, aimed at reducing the incidence and severity of hip and groin problems, ultimately enhancing athlete performance and well-being. Therefore, the purpose of this clinical commentary was to examine current evidence on common hip pathologies in hockey athletes, exploring potential associations between hip and groin pain and the biomechanics of hockey activities.

Level of Evidence

5.

Hip Capsulolabral Complex: Anatomy, Disease, MRI Features, and Postoperative Appearance

The hip is a uniquely constrained joint with critical static stability provided by the labrum, capsule and capsular ligaments, and ligamentum teres. The labrum is a fibrocartilaginous structure along the acetabular rim that encircles most of the femoral head. Labral tears are localized based on the clock-face method, which determines the extent of the tear while providing consistent terminology for reporting. Normal labral variants can mimic labral disease and can be differentiated by assessment of thickness or width, shape, borders, location, and associated abnormalities. The Lage and Czerny classification systems are currently the most well-known arthroscopic and imaging systems, respectively. Femoroacetabular impingement is a risk factor for development of labral tears and is classified according to bone dysmorphisms of the femur ("cam") or acetabulum ("pincer") or combinations of both (mixed). The capsule consists of longitudinal fibers reinforced by ligaments (iliofemoral, pubofemoral, ischiofemoral) and circular fibers. Capsular injuries occur secondary to hip dislocation or iatrogenically after capsulotomy. Capsular repair improves hip stability at the expense of capsular overtightening and inadvertent chondral injury. The ligamentum teres is situated between the acetabular notch and the fovea of the femoral head. Initially considered to be inconsequential, recent studies have recognized its role in hip rotational stability. Existing classification systems of ligamentum teres tears account for injury mechanism, arthroscopic findings, and treatment options. Injuries to the labrum, capsule, and ligamentum teres are implicated in symptoms of hip instability. The authors discuss the labrum, capsule, and ligamentum teres, highlighting their anatomy, pathologic conditions, MRI features, and postoperative appearance. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Hip Strength Profiling of Ice Hockey Athletes Across Various Joint-Specific Angles: Monitoring and Injury Implications

ABSTRACT

Secomb, JL, Kelly, M, and Dascombe, BJ. Hip strength profiling of ice hockey athletes across various joint-specific angles: monitoring and injury implications. J Strength Cond Res 37(7): e422-e429, 2023-The purpose of this research was to compare the hip adduction and abduction relative strength, adduction-to-abduction strength ratio (ADD:ABD), and interlimb asymmetries of ice hockey athletes between the typically used bilateral position and 3 unilateral positions in joint-specific angles (0°, 25°, and 50° of hip abduction) relevant to an ice hockey stride. A secondary purpose was to explore any relationships between these measures and hip and groin noncontact injuries, and self-reported pain and disability. Twenty-five semiprofessional male ice hockey athletes (26.7 ± 6.7 years) were assessed for hip abduction range of motion (ROM), hip adduction and abduction relative strength, and completed the Copenhagen Hip and Groin Outcome Score (HAGOS) questionnaire. Within-subjects repeated-measures analysis of variance revealed a significant effect for the assessment position for adduction ( F1,24 = 52.4, p < 0.01) and abduction relative strength ( F1,24 = 152.1, p < 0.01), ADD:ABD ( F1,24 = 38.9, p < 0.01), and the interlimb asymmetries for each of these variables ( F1,24 = 9.8-12.3; p < 0.01), with large strength differences observed between the bilateral assessment and all unilateral assessment positions for adduction and abduction relative strength. In addition, 4 athletes experienced a noncontact hip or groin injury within 1 month after testing, and when compared with the rest of the cohort ( n = 21) with Welch's t -tests, demonstrated significantly reduced hip abduction ROM (mean difference [MD] = -8.4 ± 2.5°; p < 0.01), sport subscale score for the HAGOS questionnaire (MD = -33.9 ± 7.1; p < 0.01), and a decline in hip adduction relative strength in the unilateral position of 50° compared with the position of 25° hip abduction (MD = -13.4 ± 3.8; p = 0.04). These results suggest that practitioners working with ice hockey athletes may benefit from profiling hip strength in these unilateral joint-specific angle positions because they provide an evidence base to determine the hip strength needs of ice hockey athletes in positions associated with skating performance and noncontact hip and groin injury mechanisms (between 25° and 50° of hip abduction).

Does the Type of Sport Influence Morphology of the Hip? A Systematic Review

BACKGROUND

Femoroacetabular impingement (FAI) has been extensively investigated and is strongly associated with athletic participation.

PURPOSE

To assess (1) the prevalence of cam-type FAI across various sports; (2) whether kinematic variation among sports influences hip morphology; and (3) whether performance level, duration, and frequency of participation or other factors influence hip morphology in a sporting population.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic search of Embase, PubMed, and the Cochrane Library was undertaken following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Prospective and retrospective case series, case reports, and review articles published after 1999 were screened, and those that met the inclusion criteria decided a priori were included for analysis.

RESULTS

The literature search identified 58 relevant articles involving 5683 participants. A total of 49 articles described a higher prevalence of FAI across various "hip-heavy" sports, including soccer, basketball, baseball, ice hockey, skiing, golf, and ballet. In studies including nonathlete controls, a greater prevalence of FAI was reported in 66.7% of studies (n = 8/12). The highest alpha angle was identified at the 1-o'clock position (n = 9/9) in football, skiing, golf, ice hockey, and basketball. The maximum alpha angle was located in a more lateral position in goalkeepers versus positional players in ice hockey (1 vs 1:45 o'clock). A positive correlation was also identified between the alpha angle and both age and activity level (n = 5/8 and n = 2/3, respectively) and between prevalence of FAI and both age and activity level (n = 2/2 and n = 4/5).

CONCLUSION

Hip-heavy sports show an increased prevalence of FAI, with specific sporting activities influencing hip morphology. There is some evidence to suggest that a longer duration and higher level of training also result in an increased prevalence of FAI.

REGISTRATION

CRD4202018001 (PROSPERO).

Hip Pain Increases With Age and Experience Level in Adult Karate Athletes: A Statewide Survey Study

Purpose

To investigate the prevalence of hip pain from labral tears and femoroacetabular impingement (FAI) in karate athletes using a statewide online survey.

Methods

An anonymous electronic survey was distributed via Qualtrics to all registered members of a statewide karate organization who were a purple belt or higher. Basic demographic information was collected as well as belt level, competitive level, and information regarding hip pain and treatment for hip pain. Microsoft Excel was used to store and analyze data.

Results

Of 180 respondents, 123 (68.3%) never had hip pain when practicing karate, and 54 (30.0%) had hip pain at some point in their karate career. Three subjects did not provide an answer and were excluded. Furthermore, of the symptomatic individuals, 52 reported the location of their hip pain, whereas 2 subjects did not. Of the symptomatic individuals (54), 32 had formal diagnoses by a medical professional, 4 (12.5%) were diagnosed with FAI of the hip, 6 (18.8%) diagnosed with a hip labral tear, 3 (9.4%) diagnosed with hip bursitis, 3 (9.4%) diagnosed with hip arthritis, and 16 (50%) had other diagnoses. The remaining 22 participants have not received a formal diagnosis by a medical professional.

Conclusions

The prevalence of hip pain in karate athletes in this survey was lower compared to athletes of other martial arts and kicking sports. No differences in the percentage of injuries were found between sex and years practiced; however a higher incidence of hip pain was found between elite status and age group. When evaluating hip pain in the karate population, orthopaedic surgeons should maintain an index of suspicion for FAI and hip labral tears.

Level of Evidence

Level IV, retrospective cross-sectional study.

Pathologic Findings on Hip Arthroscopy in High-Level Athletes Competing in Flexibility Sports

BACKGROUND

Athletes who compete in flexibility sports (FS) place unique demands on their hip joints because of the supraphysiologic range of motion required.

PURPOSE

To compare the pathologic features, outcomes, and return-to-sports (RTS) rates of high-level athletes participating in FS who underwent hip arthroscopy for femoroacetabular impingement syndrome (FAIS) and labral tear against a propensity score-matched cohort of high-level athletes participating in non-flexibility sports (NFS).

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected and retrospectively reviewed for high-level athletes who underwent primary hip arthroscopy for FAIS from April 2008 to December 2018. Patients who participated in FS such as dancing, gymnastics, martial arts, figure skating, and cheerleading were propensity score matched by body mass index, age at time of surgery, sex, sports competition level, and labral treatment to a cohort of high-level athletes participating in all other sports, such as distance running, soccer, volleyball, and softball. Baseline patient characteristics, intraoperative findings, and surgical procedures were compared. Minimum 2-year patient-reported outcome measures were compared for the modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score-Sport Specific Subscale, and visual analog scale for pain and satisfaction. Rates of secondary surgery and RTS were compared.

RESULTS

A total of 47 patients (50 hips) who participated in FS were included and propensity score matched to 130 patients (150 hips) who participated in NFS. Follow-up time was 37.5 ± 10.4 months (mean ± SD). Most patients (96.0%) were female with a mean age of 19.5 ± 7.3 years. FS athletes had significantly higher rates of femoral head cartilage lesions (Outerbridge ≥2; 12.0% vs 2.0%; P = .008) and ligamentum teres tears (48% vs 26%; P = .003). FS and NFS athletes demonstrated significant clinical improvements after surgery for all patient-reported outcome measures. Of the patients who attempted, 34 (75.6%) participating in FS were able to RTS while 11 (24.4%) were not because of ongoing hip issues. This was not significantly different than the NFS group (P = .073).

CONCLUSION

High-level athletes who participated in FS and were treated for FAIS with hip arthroscopy exhibited higher rates of femoral head cartilage lesions and ligamentum teres tears requiring debridement when compared with a benchmark group of athletes who participated in other sports. Despite this, both groups demonstrated similar improvements in outcome scores and comparable rates of RTS at minimum 2-year follow-up.

Female Athlete Hip Injuries: A Narrative Review

OBJECTIVE

In this narrative review, we highlight sex-specific anatomic and biomechanical features of the hip region in female athletes, as well as the potential impact of these characteristics on observed disparities in both intra-articular and extra-articular injury patterns between female and male athletes. It is our goal to broaden the scope of knowledge related to hip pathology in active female athletes among sports medicine providers with the hope of better optimizing sport participation and performance in female athletes.

DATA SOURCES

A literature review was conducted using PubMed database and Google Scholar search engine. Search terms included sport, female, athlete, sex differences, injury, hip, and all diagnoses discussed in this review. Cross-reference of these articles identified additional resources.

MAIN RESULTS

Sex-specific differences in both static design and dynamic function contribute to disparities in hip injury patterns between female and male athletes. Intra-articular injuries, including labral and ligamentum teres pathology, as well as extra-articular injuries, including iliopsoas tendon dysfunction, gluteal and proximal hamstring tendinopathy, ischiofemoral impingement, bone stress injuries, and certain nerve entrapment syndromes, seem to affect female athletes more commonly than male counterparts.

CONCLUSIONS

Given unique anatomic and functional considerations, the growing population of female athletes worldwide warrants specialized care and consideration. Potential predisposition to specific hip injuries should be taken into consideration during diagnostic evaluation of hip pain in the female athlete.

Return to Competitive Level of Play and Performance in Regular Golfers After Total Hip Arthroplasty: Analysis of 599 Patients at Minimum 2-Year Follow-Up

BACKGROUND

Total hip arthroplasty (THA) is performed in an increasingly younger and athletic population. Regular and competitive golfers are concerned with the likelihood of recovering their preoperative level of play. The purpose of this study was to assess the impact of primary THA on golfers' game, with a minimum follow-up of two years.

METHODS

Questionnaires were sent to the French Golf Federation's golfing members. Those who were older than 40 years and had undergone a unilateral primary THA provided information on the timing of return to play, pain during golfing, transportation mode, drive length, handicap and weekly playtime, before hip replacement, and postoperatively. In addition, data relating to the surgical procedure were collected.

RESULTS

Surveys were completed by 883 competitive golfers of which 599 were eligible for inclusion. The mean time to return to a complete 18-hole course was 4.73 months (SD 4.15, range: 0.7-36). Participants surveyed at a minimum 2 years after THA played at a higher level than before surgery with a handicap improvement of 1.8 (P < .01) and increased their mean weekly playtime from 8.8 to 9.3 hours (P = .24, NS). Eighty-eight percent reported an increased or no change in drive distance. Hip pain while playing golf decreased after surgery (6.8 to 2.5 on the visual analog scale, P < .001).

CONCLUSION

This study highlighted that hip arthroplasty allowed regular and competitive golfers to return to the course with better golfing comfort than before surgery and with an objective improvement in driving distance and level of play.

Injury risk-factor differences between two golf swing styles: a biomechanical analysis of the lumbar spine, hip and knee

The golf swing has been associated with mechanical injury risk factors at many joints. One swing, the Minimalist Golf Swing, was hypothesised to reduce lumbar spine, lead hip, and lead knee ranges of motion and peak net joint moments, while affecting swing performance, compared to golfers' existing swings. Existing and MGS swings of 15 golfers with handicaps ranging from +2 to -20 were compared. During MGS downswing, golfers had 18.3% less lumbar spine transverse plane ROM, 40.7 and 41.8% less lead hip sagittal and frontal plane ROM, and 39.2% less lead knee sagittal plane ROM. MGS reduced lead hip extensor, abductor, and internal rotator moments by 17.8, 19.7 and 43%, while lead knee extensor, abductor, adductor and external rotator moments were reduced by 24.1, 26.6, 37 and 68.8% respectively. With MGS, club approach was 2° shallower, path 4° more in-to-out and speed 2 m/s slower. MGS reduced certain joint ROM and moments that are linked to injury risk factors, while influencing club impact factors with varying effect. Most golf injuries are from overuse, so reduced loads per cycle with MGS may extend the healthy life of joints, and permit golfers to play injury-free for more years.

Performance Outcomes and Return-to-Sport Rate of National Hockey League Athletes Vary After Common Orthopedic Surgical Procedures

OBJECTIVE

Evaluate performance-based outcomes and return-to-sport rate in National Hockey League (NHL) athletes.

DESIGN

Retrospective cohort study.

SETTING

Public records. No direct patient care was provided.

PARTICIPANTS

National Hockey League athletes who underwent different orthopedic procedures were identified using public records. Three hundred thirty-seven athletes met inclusion criteria.

INDEPENDENT VARIABLES

Common orthopedic surgical procedures in NHL athletes.

MAIN OUTCOME MEASURES

Return-to-play and preoperative and postoperative performance measures were collected to calculate a position-specific performance score. Short-term and medium-term outcomes were defined as 1 and 2 to 3 seasons after surgery, respectively.

RESULTS

Three hundred seven athletes (92.6%) successfully returned to play. The number of games played during the first season after surgery compared with baseline was significantly decreased for hip arthroscopy (HA), noninstability shoulder arthroscopy (ie, shoulder arthroscopy procedure to address pathology other than shoulder instability), knee arthroscopy, and sports hernia repair (P = 0.002, 0.009, 0.03, and 0.01, respectively). The number of games played for seasons 2 and 3 after surgery was significantly decreased for both HA and noninstability shoulder arthroscopy (P = 0.01 and 0.001, respectively). Short-term postoperative performance scores were significantly decreased for HA, noninstability shoulder arthroscopy, and anterior cruciate ligament reconstruction (P = 0.00004, 0.02, and 0.02, respectively) while medium-term scores were significantly decreased for HA only (P = 0.009).

CONCLUSIONS

National Hockey League athletes return to play at a high rate after common orthopedic surgeries. However, certain procedures portend poorer performance scores and game participation than others. In particular, HA and noninstability shoulder arthroscopy have the greatest negative effect on NHL careers after surgery.

Ligamentum teres reconstruction: indications, technique and minimum 1-year results in nine patients

Ligamentum teres (LT) tear is a recognized cause of hip pain. Debridement of tears and capsule plication has shown satisfactory results. However, a group of patients with complete tears do not improve after debridement and physiotherapy. The purpose of this work was to describe the senior author's technique and clinical results for the early series of LT reconstructions. Retrospective analysis of prospectively collected data. Patients who underwent isolated LT reconstruction between 2013 and 2018. All the patients had previous debridement of a completely torn LT, capsule plication and rehabilitation. Patients who had any other associated procedure during LT reconstruction surgery and dysplastic acetabular features were excluded. Demographic and clinical data was reviewed. Complications, type of graft and modified Harris hip scores (mHHSs) were recorded preoperatively and at 1-year follow-up. Fifteen LT reconstructions were performed during the study period. Six were excluded (as they had additional procedures performed during surgery) and nine patients aged a mean 30 (range: 22-48) years old were included. The patients had a mean of 2 (range: 1-4) prior surgeries. At minimum 12 months (range: 12-24) 9/9 patients reported reduction of pain and instability symptoms with mHHSs of 84.2 (73.7-100) versus 51.7 (36.3-70.4) preoperatively (P = 0.00094). Three patients (of the total cohort of 15) underwent second-look arthroscopy (11-22 months after reconstruction). None of these patients underwent total hip replacement at a mean of 4 (range: 1-6) years. Arthroscopic LT reconstruction improved function and pain in patients with persistent pain and instability after resection of the LT.

Best Practice Guidelines for Hip Arthroscopy in Femoroacetabular Impingement: Results of a Delphi Process

BACKGROUND

Treatment algorithms for the arthroscopic management of femoroacetabular impingement (FAI) syndrome remain controversial because of a paucity of evidence-based guidance. Consequently, notable variability in clinical practice exists between different practitioners, necessitating expert consensus. The purpose of this study is to establish best practice guidelines (BPG) using formal techniques of consensus building among a group of experienced hip arthroscopists driven by the results of a systematic review and meta-analysis. The scope of these guidelines includes preoperative recommendations, intraoperative practices, and postoperative protocols.

METHODS

The validated Delphi process and the nominal group technique (NGT), used by the Centers for Disease Control and Prevention and the peer-reviewed orthopaedic literature, were used to formally derive consensus among 15 surgeons in North America. Participants were surveyed for current practices, presented with the results of a meta-analysis and systematic literature review, and asked to vote for or against the inclusion of nonleading, impartially phrased items during three iterative rounds while preserving the anonymity of participants' opinions. Agreement greater than 80% was considered consensus, and items near consensus (70% to 80% agreement) were further queried using the NGT in a moderated group session at the American Orthopaedic Society for Sports Medicine annual meeting.

RESULTS

Participants had a mean of 12.3 years of practice (range: 1 to 29 years) and performed an annual mean of 249 (range 100 to 500+) hip arthroscopies, with a combined total of approximately 52,580 procedures. Consensus was reached for the creation of BPG consisting of 27 preoperative recommendations, 15 intraoperative practices, and 10 postoperative protocols. The final checklist was supported by 100% of participants.

CONCLUSION

We developed the first national consensus-based BPG for the surgical and nonsurgical management of FAI. The resulting consensus items can serve as a tool to reduce the variability in preoperative, intraoperative, and postoperative practices and guide further research for the arthroscopic management of FAI.

Femoroacetabular Impingement in Professional Basketball Players: Return to Play, Career Length, and Performance After Hip Arthroscopy

BACKGROUND

Previous studies have demonstrated that hip arthroscopy is an effective treatment for symptomatic femoroacetabular impingement (FAI) in professional athletes across a variety of sports. However, the return-to-play rates and postoperative performance of elite basketball players after hip arthroscopy are currently unknown.

PURPOSE

To determine return-to-play rates and postoperative performance among professional basketball athletes after hip arthroscopy.

STUDY DESIGN

Case series; Level of evidence, 3.

METHODS

Eighteen professional basketball players underwent hip arthroscopy (24 hips) for symptomatic FAI between 2001 and 2016 by a single surgeon. Return to play was defined as competing in a single professional game of equal level after surgery. Data were retrospectively obtained for each player from basketball-reference.com , ESPN.com , eurobasket.com, and individual team websites. Matched controls were selected from the websites to compare performances.

RESULTS

The mean age at the time of surgery was 25.6 years, and the mean body mass index was 24.4 kg/m². All players returned to their previous levels of competition, with a mean number of 4 seasons played after surgery (median, 3; range, 1-12). The mean ± SD time between the date of surgery and return to a professional game was 7.1 ± 4.4 months. There was no change in player efficiency rating when pre- and postinjury performance were compared. When compared with controls, players undergoing surgery also had no significant decline in player efficiency rating.

CONCLUSION

Elite basketball athletes who undergo hip arthroscopy for the treatment of FAI return to their presurgical levels of competition at a high rate. These athletes demonstrate no significant overall decrease in performance upon their return to play.

Trunk forward flexion mobility in reference to postural sway in women after delivery: A prospective longitudinal comparison between early pregnancy and 2- and 6-month postpartum follow-ups

BACKGROUND

It has been documented that pregnancy-related increased connective tissue laxity may persist postpartum; however, it is still unclear for how long. This longitudinal study aimed to compare total trunk forward flexion mobility in women between their first trimester of pregnancy and at 2- and 6-month postpartum follow-ups. We also searched for a correlation between women's trunk flexibility and their postural stability in the sagittal plane.

METHODS

Seventeen healthy women participated in the study. Data were collected at their 7-12 weeks gestation appointments and at 6-10 and 25-28 weeks postpartum. At each session, the women performed a finger floor distance test, and data were collected on their waist circumference and BMI. The women's center of foot pressure mean velocity in the anterior-posterior direction was computed from 30-s long quiet-standing trials on a stationary force plate.

FINDINGS

Total trunk forward flexion mobility was significantly higher at 2 and 6 months postpartum compared to that in early pregnancy (P < 0.05). At 6 months postpartum, a moderate negative correlation between finger floor distance test values and their anterior-posterior center of foot pressure mean velocity was observed (r = -0.6, P < 0.05).

INTERPRETATION

Increased total trunk flexibility may be present in women 6 months postpartum. During that period, women with higher trunk flexibility may be more likely to present higher anterior-posterior postural sway velocity in quiet standing.

The role of the ligamentum teres in the adult hip: redundant or relevant? A review

The ligamentum teres (LT) has traditionally been described as a redundant structure with no contribution to hip biomechanics or function. There has been renewed interest in the LT as a source of hip pathology due to the high prevalence of LT pathology observed at the time of hip arthroscopy. The LT acts a secondary stabilizer to supplement the work of the capsular ligaments and works in a sling-like manner to prevent subluxation of the hip at the extremes of motion. The presence of free nerve endings within the LT indicates a definite role in pain generation, with the LT undergoing various mechanical and histological adaptations to hip pathology.

Translatory hip kinematics measured with optoelectronic surgical navigation

PURPOSE

An optoelectronic surgical navigation system was used to detect small but measurable translational motion of human hip cadavers in high-range passive motions. Kinematic data were also examined to demonstrate the role of soft tissues in constraining hip translation.

METHODS

Twelve cadaver hips were scanned using CT, instrumented for navigation, and passively taken through motion assessment. Center of the femoral head was tracked in the acetabular coordinates. Maximum non-impinging translation of the femoral head for each specimen hip was reported. This was repeated for 5 tissue states: whole, exposed to the capsule, partially or fully incised capsule, resection of the ligamentum teres and labrectomy. Femoral motions were compared to the reported value for ideal ball and socket model.

RESULTS

Whole and exposed hips underwent maximal translations of [Formula: see text] and [Formula: see text] mm, respectively. These translational motions were statistically significantly different from reported value for a purely spherical joint, [Formula: see text]. Further tissue removal almost always significantly increased maximum non-impingement translational motion with [Formula: see text].

CONCLUSION

We found subtle but definite translations in every cadaver hip. There was no consistent pattern of translation. It is possible to use the surgical navigation systems for the assessment of human hip kinematics intra-operatively and improve the treatment of total hip arthroplasty patients by the knowledge of the fact that their hips translate. Better procedure selection and implantation optimization may arise from improved understanding of the motion of this critically important human joint.

Effects of hip joint transverse plane range of motion with a modeled effusion and capsular tear: A cadaveric study

BACKGROUND

Multiple factors contribute to range of motion of the hip joint in the transverse plane: bony anatomy, hip capsule, corresponding ligaments, articular labrum, ligamentum teres, and negative intra-articular pressure. We hypothesized that violation of the negative pressure of the hip and simulation of an effusion would increase range of motion in the transverse plane in a cadaver model.

METHODS

Ten hip specimens were obtained and dissected with the femur and iliac wing mounted in a custom joint-testing rig in neutral position. Specimens were tested at 0 and at 90° of flexion with 1.5Nm internal and external rotational torque. Three conditions were assessed: (1) intact specimen, (2) an effusion modeled by a 10ml saline infusion, and (3) a capsular tear.

FINDINGS

The modeled effusion decreased rotational range of motion limits in both 0 and 90° of flexion, with a greater effect on the specimens at 0° flexion in external rotation with 4.1° less external rotation (p=0.009). A modeled capsular tear increased rotational motion limits in 0° of flexion in both internal and external rotation and in 90° flexion in internal rotation only (p<0.025).

INTERPRETATION

An effusion may decrease the rotation of the hip, and a capsular tear may increase its rotation. This should be considered in hips with traumatic capsular tears or arthroscopic portals.

Biomechanical evaluation contribution of the acetabular labrum to hip stability

PURPOSE

Knowledge of the effect of hip pathologies on hip biomechanics is important to the understanding of the development of osteoarthritis, and the contribution of the labrum to hip joint stability has had limited study. The purpose of this study was to evaluate the effect of labral injury to stability of the femoral head in the acetabular socket.

METHODS

Ten cadaver hip specimens were tested using a robotic system under four different loading conditions: axial loading (80 N) along the femoral axis and axial loading (80 N) combined with either anterior, posterior or lateral loading (60 N). The hip states were examined were intact, with a 1.5 cm capsulotomy and with a 1 cm resection of the anterosuperior labrum.

RESULTS

At 30° of flexion, under axial load, the displacement of the hip with capsulotomy and labral resection (9.6 ± 2.5 mm) was significantly larger then the hip with capsulotomy alone (5.6 ± 4.1 mm, p = 0.005) and the intact hip (5.2 ± 3.8 mm, p = 0.005). Also, at 30° of flexion, the displacement under combined axial and anterior/posterior load was increased with capsulotomy and labral resection.

CONCLUSION

The acetabular labrum provides stability to the hip joint in response to a distraction force and combined distraction and translation forces. One centimetre of labral resection caused significant displacement ("wobbling" effect) of the femoral head within the acetabulum with normal range of motion. Successful labral repair could be crucial for restoration of the hip biomechanics and prevention of coxarthrosis.

Atraumatic tears of the ligamentum teres are more frequent in professional ballet dancers than a sporting population

OBJECTIVES

To compare the frequency of atraumatic ligamentum teres (LT) tear in professional ballet dancers with that of athletes, and to determine the relationship with clinical and imaging findings.

METHODS

Forty-nine male and female professional ballet dancers (98 hips) and 49 age and sex-matched non-dancing athletes (98 hips) completed questionnaires on hip symptoms and physical activity levels, underwent hip rotation range of movement (ROM) and hypermobility testing, and 3.0-Tesla magnetic resonance imaging (3 T MRI) on both hips to detect LT tears, acetabular labral tears, and articular cartilage defects, and to measure the lateral centre edge angles (LCE).

RESULTS

A higher frequency of LT tear was found in dancers (55 %) compared with athletes (22 %, P = 0.001). The frequency and severity of LT tears in dancers increased with older age (P = 0.004, P = 0.006, respectively). The Hip and Groin Outcome Score (HAGOS) pain scores or hip rotation ROM did not differ significantly among participants with normal, partial, or complete tears of LT (P > 0.01 for all). Neither the frequency of generalised joint hypermobility (P = 0.09) nor the LCE angles (P = 0.32, P = 0.16, left and right hips respectively) differed between those with and those without LT tear. In most hips, LT tear co-existed with either a labral tear or a cartilage defect, or both.

CONCLUSION

The higher frequency of atraumatic LT tears in professional ballet dancers suggests that the LT might be abnormally loaded in ballet, and caution is required when evaluating MRI, as LT tears may be asymptomatic. A longitudinal study of this cohort is required to determine if LT tear predisposes the hip joint to osteoarthritis.

The ligamentum capitis femoris: anatomic, magnetic resonance and computed tomography study

The objective of the study was to describe the normal anatomy of the ligamentum capitis femoris and to determine the neurovascular structures potentially at risk during its reconstruction. Ten cadaveric specimens of the ligamentum capitis femoris (LCF) were dissected and photographed. Magnetic resonance (MR) and Computed tomography (CT) arthrography evaluation of the anatomy of the LCF in 30 hips were performed to measure length of the ligament and to study the proximity of neurovascular structures. The anatomical study showed that the LCF has a pyramidal structure and a banded appearance. The thickness of the medial wall of the acetabulum 3 mm superior to the inferior acetabular boundary was found to be 6.7 mm (4-9 mm) at point 1 (anterior), 4.1 mm (3-7 mm) at point 2 (central), and 6.5 mm (4-9 mm) at point 3 (posterior). Central anchors or screws were found to lie within 1.7 cm (1.6-1.9 cm) of the external iliac vein and artery. Angulation of anchors in the anterior and posterior columns in the axial plane with respect to acetabular fossa floor (the Optimal Angulation Angle or OAA), is safer (0 to 45º the safest optimal angles). The sagittal angulation created by the safe pathway in the anterior and posterior columns with respect to the plane of the facies lunata in this area was also measured and termed the Optimal Angle of Penetration (OAP) with normal values being: 110º (102-123º) for the posterior column and 90º (85-94º) for the anterior column. Our results suggest that reconstruction of the LCF can be safely performed if these guidelines are followed.

Hip arthroscopy for the treatment of femoroacetabular impingement: a comparative study between the classic and the outside-in access

PURPOSE

To compare the functional outcomes of patients undergoing arthroscopic surgery for the treatment of femoroacetabular impingement (FAI) performed with either the classic or the outside-in access to the hip.

METHODS

Data regarding patients arthroscopically treated for FAI from January 2009 to June 2013 were retrospectively reviewed and compared regarding the type of access.

RESULTS

101 hips (91 patients) with a minimum of 12 months follow-up (mean 22 months, range 12-40 months) were included. Classic access was used in 48 cases while outside-in access was performed in 53 cases. Mean age was 37 years (range 15.7-59.6 years). Both groups were comparable with respect to preoperative characteristics. Mean operating time was 162 minutes for the outside-in group and 172 minutes for the classic access group. Complications between both groups showed no statistically significant differences but for the presence of heterotopic calcifications, which was more frequently observed regarding the outside-in access. Outcomes measured by the modified Harris Hip Score showed no overall differences regarding both types of access, except for patients under 35 years old, where there was a statistically significant increase in excellent and good outcomes with the use of the classic access in comparison to the outside-in technique. Postoperative hip motion was also significantly higher in the classic access group.

CONCLUSIONS

No differences have been found in outcomes regardless the access used. Classic access seems to offer a higher postoperative range of motion and lower risk of heterotopic ossifications.

Femoral Head Avascular Necrosis Is Not Caused by Arthroscopic Posterolateral Femoroplasty

This study was conducted to identify the risk of avascular necrosis of the femoral head after arthroscopic femoroplasty extending to the posterolateral femoral neck, the source of the primary blood supply to the femoral head. Cam lesions of femoroacetabular impingement are typically anterior along the junction of the femoral head and neck. However, anatomic variations can involve the posterolateral vascular region of the femoral head and neck. Femoroplasty involving this vascular region can lead to injury to the blood supply to the femoral head, with subsequent avascular necrosis. If the posterolateral portion of the cam lesion is preserved, persistent femoroacetabular impingement may occur. A retrospective review identified 112 patients who underwent arthroscopic femoroplasty for femoroacetabular impingement over a 2-year period. Of these patients, 14 had femoroplasty that extended to the posterolateral femoral head. Of this group, 5 had undergone magnetic resonance imaging (MRI) after femoroplasty and the other 9 were contacted to undergo MRI of the hip to evaluate for avascular necrosis. A radiologist and the senior author evaluated all MRI scans specifically for avascular necrosis of the femoral head. All procedures were performed by the senior author. Mean age of the 14 patients (8 women and 6 men) with femoroplasty that extended into the posterolateral vascular region of the femoral head was 44 years (range, 23-69 years). All 14 patients underwent MRI evaluation of the affected hip a mean of 25 months (range, 7-44 months) after femoroplasty. No MRI scans showed evidence of avascular necrosis of the femoral head. Femoroplasty of the posterolateral vascular region of the femoral head is not associated with avascular necrosis. Patients with femoroacetabular impingement and a cam lesion extending to the posterolateral femoral head can undergo femoroplasty of this region without the development of avascular necrosis. [Orthopedics. 2016; 39(3):177-180.].

Hip joint biomechanics during gait in people with and without symptomatic femoroacetabular impingement

Femoroacetabular impingement (FAI) is a morphological hip condition that can cause hip/groin pain and impaired function in younger active adults, and may lead to stiffness, muscle weakness, structural damage, and hip osteoarthritis. Understanding the impairments associated with FAI is crucial to guide treatment and rehabilitation strategies. Evidence is limited and conflicting about whether hip biomechanics are impaired during walking in people with symptomatic FAI. The objective of this study was to determine whether kinematics and kinetics during gait differ between people with symptomatic FAI and control participants. Fifteen participants diagnosed with symptomatic cam-type or combined (cam plus pincer) FAI who were scheduled for arthroscopic surgery and 14 age-, and sex-matched disease-free controls underwent three-dimensional gait analysis. Tri-planar hip kinematics and kinetics were compared between the two groups. There were limited significant between-group differences with respect to spatiotemporal variables. Participants with FAI walked with less range of motion in the sagittal plane during a gait cycle, but did not exhibit any significant kinematic differences in the frontal or transverse planes. There were no systematic differences in kinetics between the groups in any plane. Findings suggest that individuals with symptomatic FAI have minimal impairments in gait biomechanics. Although these individuals demonstrate reduced hip joint motion in the sagittal plane, the size of the difference is small and its significance for symptoms and function is unclear. More pronounced deficits in hip kinetics and kinematics may be evident during functional tasks that challenge the hip towards the position of impingement.

Femoroacetabular Impingement in Elite Ice Hockey Goaltenders: Etiological Implications of On-Ice Hip Mechanics

BACKGROUND

Femoroacetabular impingement (FAI) is particularly prevalent in ice hockey. The butterfly goalie technique is thought to involve extreme ranges of hip motion that may predispose goaltenders to FAI.

PURPOSE

To quantify hip mechanics during 3 common goaltender movements and interpret their relevance to the development of FAI.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Fourteen collegiate and professional goaltenders performed skating, butterfly save, and recovery movements on the ice. Hip mechanics were compared across the 3 movements.

RESULTS

The butterfly did not exhibit the greatest range of hip motion in any of the 3 planes. Internal rotation was the only hip motion that appeared close to terminal in this study. When subjects decelerated during skating—shaving the blade of their skate across the surface of the ice—the magnitude of peak hip internal rotation was 54% greater than in the butterfly and 265% greater than in the recovery. No movement involved levels of concomitant flexion, adduction, and internal rotation that resembled the traditional impingement (FADIR) test.

CONCLUSION

The magnitude of internal rotation was the most extreme planar hip motion (relative to end-range) recorded in this study (namely during decelerating) and appeared to differentiate this cohort from other athletic populations. Consequently, repetitive end-range hip internal rotation may be the primary precursor to symptomatic FAI in hockey goaltenders and provides the most plausible account for the high incidence of FAI in these athletes. Resection techniques should, therefore, focus on enhancing internal rotation in goaltenders, compared with flexion and adduction. While the butterfly posture can require significant levels of hip motion, recovering from a save and, in particular, decelerating during skating are also demanding on goaltenders' hip joints. Therefore, it appears critical to consider and accommodate a variety of sport-specific hip postures to comprehensively diagnose, treat, and rehabilitate FAI.

Influence of capsular repair versus unrepaired capsulotomy on 2-year clinical outcomes after arthroscopic hip preservation surgery

PURPOSE

The primary objective of this study was to determine whether capsular management technique influences clinical outcomes at a minimum of 2 years after arthroscopic hip preservation surgery.

METHODS

A retrospective review of prospectively collected data was conducted to determine the relative influence of 2 capsular management strategies on clinical outcomes: unrepaired capsulotomy (group A) and capsular repair (group B). Four hundred three patients who had undergone arthroscopic hip preservation surgery met the inclusion criteria and had 2-year outcome data available. All patients completed 4 patient-reported outcome (PRO) questionnaires preoperatively and at a minimum of 2 years' follow-up. These included the Hip Outcome Score-Activities of Daily Living (HOS-ADL) and Hip Outcome Score-Sport-Specific Subscale (HOS-SSS) subsets, Non-Arthritic Hip Score (NAHS), and modified Harris Hip Score (mHHS).

RESULTS

Group A included 235 patients and group B, 168. The mean age of all patients at final follow-up was 36.9 years. Patients in group A were significantly older (42.3 years v 29.4 years, P < .0001) and had a significantly higher body mass index (26.8 kg/m(2)v 22.9 kg/m(2), P < .0001) compared with group B. In addition, female patients were more likely than male patients to undergo capsular repair (136 female patients v 32 male patients, P < .0001). Patients in group A also showed greater chondral damage by acetabular labrum articular disruption classification (P = .0081) and reduced preoperative PROs (HOS-ADL of 60.5 v 66.0, P = .087; HOS-SSS of 37.0 v 46.4, P = .0002; NAHS of 54.6 v 62.2, P < .0001; mHHS of 58.7 v 64.4, P = .0009; and visual analog scale score of 6.3 v 5.84, P = .028). All PROs showed statistically significant improvements for both groups at a minimum follow-up of 2 years (HOS-ADL, 60.5 to 82.2 in group A and 66 to 86.1 in group B; HOS-SSS, 36.9 to 67.3 and 46.4 to 71.2, respectively; NAHS, 54.6 to 79 and 62.2 to 82.8, respectively; visual analog scale score, 6.3 to 3.1 and 5.8 to 2.9, respectively; and mHHS, 58.7 to 81 and 64.4 to 83.8, respectively; P < .0001 for all differences). Furthermore, group B showed greater overall improvements than group A for the HOS-ADL (P = .03) and NAHS (P = .03) on uncorrected univariate analysis, but significance was lost once we controlled for confounding variables.

CONCLUSIONS

Arthroscopic capsular repair, used in conjunction with arthroscopic hip preservation surgery, appears to be safe and did not negatively influence clinical outcomes in this study. When confounding variables were controlled for, the use of capsular repair did not show clinically relevant superiority over the use of unrepaired capsulotomy.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Clinical and instrumented measurements of hip laxity and their associations with knee laxity and general joint laxity

CONTEXT

Hip-joint laxity may be a relevant anterior cruciate ligament injury risk factor. With no devices currently available to measure hip laxity, it is important to determine if clinical measurements sufficiently capture passive displacement of the hip.

OBJECTIVE

To examine agreement between hip internal-external-rotation range of motion measured clinically (HIER(ROM)) versus internal-external-rotation laxity measured at a fixed load (HIER(LAX)) and to determine their relationships with knee laxity (anterior-posterior [KAP(LAX)], varus-valgus [KVV(LAX)], and internal-external rotation [KIER(LAX)]) and general joint laxity (GJL). Design : Cross-sectional study.

SETTING

Controlled research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Thirty-two healthy adults (16 women, 16 men; age = 25.56 ± 4.08 years, height = 170.94 ± 10.62 cm, weight = 68.86 ± 14.89 kg).

MAIN OUTCOME MEASURE(S)

Participants were measured for HIER(ROM), HIER(LAX) at 0° and 30° hip flexion (-10 Nm, 7 Nm), KAP(LAX) (-90 N to 133 N), KVV(LAX) (±10 Nm), KIER(LAX) (±5 Nm), and GJL. We calculated Pearson correlations and 95% limits of agreement between HIER(ROM) and HIER(LAX)_0° and HIER(LAX)_30°. Correlation analyses examined the strength of associations between hip laxity, knee laxity, and GJL.

RESULTS

The HIER(ROM) and HIER(LAX) had similar measurement precision and were strongly correlated (r > 0.78). However, HIER(ROM) was systematically smaller in magnitude than HIER(LAX) at 0° (95% limits of agreement = 29.0° ± 22.3°) and 30° (21.4° ± 19.3°). The HIER(ROM) (r = 0.51-0.66), HIER(LAX)_0° (r = 0.52-0.69) and HIER(LAX)_30° (r = 0.53-0.76) were similarly correlated with knee laxity measures and GJL. The combinations of KVV(LAX) and either HIER(ROM), HIER(LAX)_0°, or HIER(LAX)_30° (R2 range, 0.42-0.44) were the strongest predictors of GJL.

CONCLUSIONS

Although HIER(ROM) and HIER(LAX) differed in magnitude, they were measured with similar consistency and precision and were similarly correlated with knee laxity and GJL measures. Individuals with greater GJL also had greater hip laxity. These findings are relevant to clinicians and investigators conducting prospective risk factor studies, given the need for accessible, efficient, and low-cost alternatives for characterizing an individual's laxity profile.

Ice hockey goaltender rehabilitation, including on-ice progression, after arthroscopic hip surgery for femoroacetabular impingement

Ice hockey goaltenders, especially those who employ the butterfly technique, are a specialized population of athletes because of the unique physical demands that the position places on their lower extremities, specifically at the hip. It is no surprise that hip injuries are a common occurrence among goalies. A review of the biomechanical literature has demonstrated that stresses on the hip while in flexion and end-range internal rotation, the position goaltenders commonly use, put the hip at risk for injury and are likely a major contributing factor to overuse hip injuries. The stress on a goaltender's hip can potentially be further intensified by the presence of bony deformities, such as cam- or pincer-type femoroacetabular impingement, which can lead to chondrolabral junction and articular cartilage injuries. There have been few published reports of goaltenders' functional outcomes following femoroacetabular impingement surgery, and, to our knowledge, no studies have yet identified the specific challenges presented in the rehabilitation of goaltenders following femoroacetabular impingement surgery. The present clinical commentary describes a 6-phase return-to-skating program developed as part of a rehabilitation protocol to aid hockey goaltenders recovering from surgery.

Arthroscopic capsulotomy, capsular repair, and capsular plication of the hip: relation to atraumatic instability

PURPOSE

The purpose of this systematic review was to critically evaluate the available literature exploring the role of the hip joint capsule in the normal state (stable) and pathologic states (instability or stiffness). Furthermore, we examined the various ways that arthroscopic hip surgeons address the capsule intraoperatively: (1) capsulotomy or capsulectomy without closure, (2) capsulotomy with closure, and (3) capsular plication.

METHODS

Two independent reviewers (B.D.G. and B.G.D.) performed a systematic review of the literature using PubMed and the reference lists of related articles by means of defined search terms. Relevant studies were included if these criteria were met: (1) written in English, (2) Levels of Evidence I to V, (3) focus on capsule and its role in hip stability, and (4) human studies and reviews. Articles were excluded if they evaluated (1) total hip arthroplasty constructs using bony procedures or prosthetic revision, (2) developmental dysplasia of the hip where reorientation osteotomies were used, (3) syndromic instability, and (4) traumatic instability with associated bony injury.

RESULTS

By use of the search method described, 5,085 publications were reviewed, of which 47 met appropriate criteria for inclusion in this review. Within this selection group, there were multiple publications that specifically addressed more than 1 of the inclusion criteria. Relevant literature was organized into the following areas: (1) capsular anatomy, biomechanics, and physiology; (2) the role of the capsule in total hip arthroplasty stability; (3) the role of the capsule in native hip stability; and (4) atraumatic instability and capsulorrhaphy.

CONCLUSIONS

As the capsuloligamentous stabilizers of the hip continue to be studied, and their role defined, arthroscopic hip surgeons should become facile with arthroscopic repair or plication techniques to restore proper capsular integrity and tension when indicated.

LEVEL OF EVIDENCE

Level IV, systematic review.

Catastrophic failure of hip arthroscopy due to iatrogenic instability: can partial division of the ligamentum teres and iliofemoral ligament cause subluxation?

Hip arthroscopy is an evolving surgical tool, and with any new procedure, it is important to learn from the complications encountered. A patient with mild hip dysplasia and a symptomatic labral tear underwent uneventful hip arthroscopy and labral repair including partial debridement of a hypertrophied ligamentum teres. Despite preservation of the labrum, no pincer resection, and a modest capsulotomy, 3 months, subluxation and joint space narrowing were noted. One year, end-stage arthritis was present, requiring total hip replacement. Instability after hip arthroscopy is due to a number of factors, including excessive rim trimming, capsulotomy, overzealous labral resection, or inadequate labral repair. This report emphasizes the importance of the ligamentum teres and small disruptions of the capsule in patients with mild dysplasia.

The prevalence of radiographic hip abnormalities in elite soccer players

BACKGROUND

Hip injuries, both intra- and extra-articular, are becoming a more commonly recognized, diagnosed, and treated injury in athletes of all competitive levels. Our goal is to establish a previously undefined value in this athletic population--the prevalence of radiographic hip abnormalities in elite soccer athletes.

PURPOSE

To provide a foundation for the future body of literature regarding hip pathologic abnormalities and "at-risk" hips in athletes of all ages and levels of participation.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

We retrospectively reviewed the anteroposterior pelvis and frog-leg lateral radiographs of 95 elite male and female soccer players to determine the prevalence of hip abnormalities. Athletes with a history of hip or groin injuries were included. Multiple radiographic parameters were used to assess the presence of cam and pincer-type femoroacetabular impingement. Measurements were conducted by a blinded, sports medicine fellowship-trained orthopaedic surgeon with experience in treating hip disorders.

RESULTS

In total, 72% (54/75) of male and 50% (10/20) of female players demonstrated some evidence of radiographic hip abnormality. Cam lesions were present in 68% (51/75) of men (76.5% [39/51] bilateral involvement) and 50% (10/20) of women (90% [9/10] bilateral involvement). Pincer lesions were present in 26.7% (20/75) of men and 10% (2/20) of women. The average male alpha angle overall was 65.6°. Cam-positive hips averaged 70.7°. The average female alpha angle overall was 52.9°, with cam-positive hips averaging 60.8°.

CONCLUSION

The prevalence of radiographic hip abnormalities in elite soccer athletes is considerable, particularly in young male athletes. The establishment of the prevalence of these findings represents the first step in identifying the relationship between radiographic abnormalities and injuries of the hip and groin in athletes.

Surgery for femoroacetabular impingement using a minimally invasive anterolateral approach: analysis of 118 cases at 2.2-year follow-up

INTRODUCTION

Treatment of femoroacetabular impingement (FAI) has progressed over time from using long incisions and dislocation to using arthroscopic surgery. Minimally invasive treatment has rarely been evaluated and a minimally invasive, anterolateral approach has not been used up to now for this indication. A prospective, on-going study was performed to evaluate surgical treatment of FAI with a minimally invasive, anterolateral approach.

HYPOTHESIS

Femoral neck, acetabulum and labrum abnormalities can be corrected without significant morbidity using a minimally invasive, anterolateral approach without dislocation.

PATIENTS AND METHODS

Treatment of 120 FAI cases (108 patients, 16 women, 92 men, 12 bilateral cases during one surgical session), average age: 34 years (18.9-63.5 years), was done prospectively and in an uninterrupted series. Two cases were lost to follow-up; 106 patients (118 FAI cases) were evaluated with a follow-up of at least 1 year. Assessments consisted of the Non-Arthritic Hip Score (NAHS), WOMAC, measurement of internal rotation with 90° flexion and the Nötzli alpha angle on an A/P radiograph in 45° of flexion, 45° abduction and 30° external rotation.

RESULTS

Blood loss averaged 1.2g/dl (range 0.5 to 2.7g/dl) and the average operative time was 44.9 minutes (range 30 to 65). With an average follow-up of 2.2 years (range 12 to 54 months), the NAHS changed by 32.5 points (P<0.0001), internal rotation by 19.0° (P<0.0001) and the alpha angle by -24.9° (P<0.0001). Eight surgical revisions were required (6.8%) (four haematomas, two capsular debridement, two additional procedures on the acetabulum) and these had a good outcome; there were no nerve-related or infection-related complications. Four failures (3.5%) were revised by arthroplasty (two patients experienced residual pain and two patients rapidly progressed to osteoarthritis). Eighteen cases progressed by only one Tönnis stage. Brooker stage II and III ossification were observed in 12 cases (10.2%) but these did not affect the functional score and range of motion improvement.

DISCUSSION

This approach, which can be learned and performed quickly, does not require any specific materials and yields a reliable surgical procedure without major complications. This short-term study, where the central cartilaginous compartment was not explored and the labrum was not sutured, comprised a consecutive, non-selected series of patients (independent of age, weight, osteoarthritis stage) and had encouraging results.

LEVEL OF EVIDENCE

Level III, prospective study, no control group.

Emerging topics on the hip: ligamentum teres and hip microinstability

Microinstability and ligament teres lesions are emergent topics on the hip pathology. These entities are an increasingly recognized cause of persistent hip pain and should be considered in the differential diagnosis of the patient with hip pain. Conventional (non-arthrographic) CT and MR have a very limited role in the evaluation of these entities. CTa and MRa have emerged as the modalities of choice for pre-operative imaging of ligamentum teres injuries and microinstability. To date, pre-operative imaging detection of these pathologies is not widespread but with appropriate imaging and a high index of suspicion, preoperative detection should improve. This article discusses current concepts regarding anatomy, biomechanics, clinical findings, diagnosis and treatment of ligament teres lesions and microinstability.

The labro-acetabular complex

The human hip is subjected to several hundred million loading cycles during a lifetime. Hip instability and femoro-acetabular impingement cause damage to the rim of the acetabulum. The acetabular rim is a highly specialized structure known as the labro-acetabular complex. A unidirectional flow of synovial fluid has been identified in this region. The synovial fluid circulation is driven by the bellows-like movement of the zona orbicularis and depends on hip flexion and extension. Surgical repair of the damaged labro-acetabular complex should satisfy two goals. First, the labrum should be preserved or reconstructed when possible. Second, the precipitating cause of the labro-acetabular damage must be addressed.

Secondary capsular laxity of the hip

We describe a hip condition with a recognisable pattern of clinical signs and radiological findings thought to result from chronic capsular injury. Between June 2006 and October 2009, ten patients (11 hips), four men and six women, were identified with an abnormality of external rotation at the hip joint. A detailed history and clinical examination was undertaken for each patient. Dynamic magnetic resonance imaging of symptomatic and control hips were evaluated for bony and soft tissue appearances. The relative positions of the femoral head and the acetabulum were assessed through a range of hip rotation. In affected hips, a loss of normal log roll recoil was observed. Three distortions of the iliofemoral ligament were identified on axial MR images; thinning at the lateral insertion of the ligament, attenuation of the iliofemoral ligament most noticeably on maximum external rotation (60º) and the appearance of laxity despite full external rotation. Stability of the hip is dependent on the interaction of bony and soft tissue structures. Hip instability is recognised in dysplasia and is known to lead to premature degeneration of the joint. Chronic capsular injury may destabilise previously asymptomatic hips with subsequent development of pain in young, active patients.

Arthroscopic treatment of unstable total hip replacement

Hip arthroscopy may be useful in the diagnosis and treatment of apparently well-implanted but unstable total hip replacement prostheses. We present 2 cases of arthroscopically assisted capsular tightening in unstable total hip replacements. Both cases had significant capsular laxity. Case 2 had impingement of the lower part of the acetabulum with the lesser trochanter that caused hip dislocation. Early revision surgery can be avoided with the use of this technique in selected cases of unstable total hip replacements.

Reliability of clinical diagnosis in intraarticular hip diseases

This study investigated the ability of experienced orthopedic surgeons to agree on a diagnosis of labral tear, femoroacetabular impingement (FAI), and capsular laxity using clinical examination. Eight patients under the care of an experienced hip arthroscopist underwent independent clinical evaluations by six orthopedic surgeons who specialized in management hip pain. No attempt was made to regulate the evaluation process as surgeons performed their examination as they would in their own practice. Average subject age was 27 years (19-47 years) with five females and three males. Subjects subsequently underwent arthroscopic surgery by the treating surgeon. Surgical findings were recorded with respect to the presence or absence of a labral tear, FAI, and/or capsular laxity. The percent agreement between the surgical findings and clinical examinations were determined. Surgical findings noted four subjects had a labral tear, five FAI, and three laxity. Based on clinical examination, surgeons agreed 63, 65 and 58% of the time with the surgical diagnosis of labral tear, FAI, and capsular laxity, respectively. The level of agreement did not seem to be dependent on the size or type of labral tear. Also, the ability to detect FAI did not seem to depend on whether the lesion was a cam, pincer, combined cam/pincer or size of the cam lesion. This study offers support that clinical examination techniques used for making a diagnosis needs to be improved and standardized if they are to be useful in diagnosing specific pathologies found with arthroscopic hip surgery.

Arthroscopic labral repair and treatment of femoroacetabular impingement in professional hockey players

BACKGROUND

Hip injuries are common among professional hockey players in the National Hockey League (NHL).

HYPOTHESIS

Professional hockey players will return to a high level of function and ice hockey after arthroscopic labral repair and treatment of femoroacetabular impingement.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Twenty-eight professional hockey players (NHL) were unable to perform at the professional level due to unremitting and debilitating hip pain. Players underwent arthroscopic labral repair and were treated for femoroacetabular impingement from March 2005 to December 2007. Players who had bilateral hip symptoms were excluded. Athletes completed the Modified Harris Hip Score preoperatively and postoperatively and also completed a patient satisfaction questionnaire postoperatively. Return to sport was defined as the player resuming skating for training or participation in the sport of ice hockey.

RESULTS

The average age at the time of surgery was 27 years (range, 18-37). There were 11 left hips and 17 right hips. Player positions included 9 defensemen, 12 offensive players, and 7 goaltenders. All players had labral lesions that required repair. In addition, all patients had evidence of femoroacetabular impingement at the time of surgery. The average time to return to skating/hockey drills was 3.4 months. The average time to follow-up was 24 months (range, 12-42). The Modified Harris Hip Score improved from 70 (range, 57-100) preoperatively to an average of 95 (range, 74-100) at follow-up. The median patient satisfaction was 10 (range, 5-10). Two players had reinjury and required additional hip arthroscopy.

CONCLUSION

Treatment of femoroacetabular impingement and labral lesions in professional hockey players resulted in successful outcomes, with high patient satisfaction and prompt return to sport.

Arthroscopy of the hip in children and adolescents

Intra-articular abnormalities of the hip, such as labral tears, loose bodies, chondral lesions, ligamentum teres tears and femoral acetabular impingement are increasingly being recognized in the pediatric age group. Evaluation for these abnormalities starts with a good history and physical exam. Radiographic imaging with plain films and magnetic resonance imaging help confirm the clinical impression. Arthroscopy of the hip can be utilized to diagnose and treat these abnormalities. Arthroscopy of the hip is a challenging procedure with a learning curve that requires a thorough knowledge of the anatomy of the hip. The hip is a deeply recessed joint that has a large muscular envelope, thick joint capsule and convex and concave surfaces of the femoral head and acetabulum, respectively. The normal anatomy may be distorted due to childhood developmental disorders such as hip dysplasia, Legg-Calve-Perthes Disease and Slipped Capital Femoral Epiphysis that adds additional challenges to the arthroscopist. Isolated intra-articular abnormalities occur rarely and an underlying morphologic abnormality should be identified which also requires management. Complications can be minimized with attention to detail.

Complications of arthroscopic femoroacetabular impingement treatment: a review

Recent developments in hip arthroscopy techniques and technology have made it possible in many cases to avoid open surgical technique for treating pincer-type and cam-type femoroacetabular impingement and rather treating it arthroscopically. Early reports suggest favorable results using arthroscopic techniques. The frequency of complications reported for hip arthroscopy for all indications is generally less than 1.5%, suggesting the procedure is safe. Little information is available on complications directly related to the arthroscopic treatment of femoroacetabular impingement. Failure to recognize and treat or incompletely reshape impingement deformities may be the most frequent cause for a second hip arthroscopy and redébridement of the deformity. There has been no report of avascular necrosis related to the arthroscopic treatment of femoroacetabular impingement; only one femoral neck fracture after arthroscopic cam remodeling has been reported in a large series of patients. Other clinical concerns include hip dislocation secondary to extensive capsulotomies or overresection of the anterior acetabular rim in the case of pincer impingement.

The interrater reliability of 4 clinical tests used to assess individuals with musculoskeletal hip pain

STUDY DESIGN

Descriptive and reliability study.

OBJECTIVES

To evaluate the interrater reliability of the FABER test, flexion-internal rotation-adduction impingement test, log roll test, and the palpation of the greater trochanter for tenderness.

BACKGROUND

Clinical examination for individuals with musculoskeletal hip pain is believed to provide critical diagnostic information. However, there is very limited information in the literature on the reproducibility of examination techniques for the hip region.

METHODS AND MEASURES

Seventy subjects were evaluated prospectively by an orthopaedic surgeon and physical therapist. Subjects had a mean age of 42 years (range 18-76 years; SD 15.4) and included 32 (46%) females and 38 (54%) males. Subject diagnoses were as follows: degenerative joint disease (n=27 [39% of subjects]), labral tear (n=35 [50% of subjects]), femoroacetabular impingement (n=48 [69% of subjects]), capsular laxity (n=28 [40% of subjects]), trochanteric bursitis (n=29 [41% of subjects]), iliopsoas tendonitis (n=10 [14% of subjects]), and adductor strain (n=2 [3% of subjects)]. Subjects could have more than 1 diagnosis. Kappa, prevalence indexes, bias indexes, and maximal attainable kappa were calculated.

RESULTS

Kappa (kappa) coefficients with 95% confidence intervals (CI) were as follows: FABER test kappa was 0.63 (95% CI: 0.43-0.83); flexion-internal rotation-adduction impingement test kappa was 0.58 (95% CI: 0.29-0.87); log roll test kappa was 0.61 (95% CI: 0.41-0.81); and greater trochanteric tenderness kappa was 0.66 (95% CI: 0.48-0.84). Bias indexes were low (0.06-0.08) for all 4 tests while prevalence indexes were low (0.03-0.37) for 3 of the 4 tests. The flexion-internal rotation-adduction impingement test had a high prevalence index (0.76), with a higher proportion of positive tests.

CONCLUSION

The kappa values for the FABER test, log roll test, and assessment of greater trochanteric tenderness were greater than 0.40 (fair level of agreement) at a 95% confidence level. The low reliability obtained for the flexion-internal rotation-adduction impingement test may be related to a prevalence concern.

Femoroacetabular impingement in 45 professional athletes: associated pathologies and return to sport following arthroscopic decompression

Femoroacetabular impingement (FAI) occurs when an osseous abnormality of the proximal femur (cam) or acetabulum (pincer) triggers damage to the acetabular labrum and articular cartilage in the hip. Although the precise etiology of FAI is not well understood, both types of FAI are common in athletes presenting with hip pain, loss of range-of-motion, and disability in athletics. An open surgical approach to decompressing FAI has shown good clinical outcomes; however, this highly invasive approach inherently may delay or preclude a high level athlete's return to play. The purpose of this study was to define associated pathologies and determine if an arthroscopic approach to treating FAI can allow professional athletes to return to high-level sport. Hip arthroscopy for the treatment of FAI allows professional athletes to return to professional sport. Between October 2000 and September 2005, 45 professional athletes underwent hip arthroscopy for the decompression of FAI. Operative and return-to-play data were obtained from patient records. Average time to follow-up was 1.6 years (range: 6 months to 5.5 years). Forty two (93%) athletes returned to professional competition following arthroscopic decompression of FAI. Three athletes did not return to play; however, all had diffuse osteoarthritis at the time of arthroscopy. Thirty-five athletes (78%) remain active in professional sport at an average follow-up of 1.6 years. Arthroscopic treatment of FAI allows professional athletes to return to professional sport.