Ehlers-Danlos Syndrome: Arthroscopic Management for Extreme Soft-Tissue Hip Instability

PURPOSE

To present outcomes in a series of patients with Ehlers-Danlos syndrome (EDS)-hypermobility type who underwent hip arthroscopy for associated hip pain and extreme capsular laxity.

METHODS

A retrospective chart review identified 16 hips with confirmed EDS--hypermobility type that underwent hip arthroscopy for continued pain and capsular laxity. All patients had complaints of "giving way" and pain, an easily distractible hip with manual traction under fluoroscopy, and a patulous capsule at the time of surgery. No patient had osseous evidence of acetabular hip dysplasia or prior confirmed hip dislocation. Outcomes were evaluated preoperatively and postoperatively with the modified Harris Hip Score (mHHS), the 12-Item Short Form Health Survey (SF-12), and a visual analog scale (VAS) for pain.

RESULTS

Evidence of symptomatic femoroacetabular impingement (FAI) was found in 15 hips (93.8%). The 16th hip had subjective giving way with a positive anterior impingement test and was easily distractible, had a labral tear, and had a patulous capsule at the time of surgery. The mean follow-up period was 44.61 months (range, 12 to 99 months). The mean preoperative lateral center-edge angle was 31.8° (range, 25° to 44°), and the mean Tönnis angle was 3.6° (range, -2° to 8°). Mean femoral version measured on computed tomography (CT) scans was 19.2° (range, -4.0° to 31.0°). Of the hips, 13 underwent primary arthroscopy and 3 underwent revision. All hips underwent hip arthroscopy with an interportal capsular cut only and arthroscopic capsular plication. There were 13 labral repairs, 2 labral debridements, 8 rim resections, 15 femoral resections, 2 psoas tenotomies, and 1 microfracture. Improved stability with an inability to distract the hip with manual traction under fluoroscopy was noted in all hips after plication. The mean alpha angle preoperatively was 58.7° on anteroposterior radiographs and 63.6° on lateral radiographs compared with 47.4° and 46.1°, respectively, postoperatively. There were significant improvements for all outcomes (mHHS, P = .002; SF-12 score, P = .027; and VAS score, P = .0004). The mean mHHS, SF-12 score, and VAS score were 45.6 points, 62.4 points, and 6.5 points, respectively, preoperatively compared with 88.5 points, 79.3 points, and 1.6 points, respectively, at a mean follow-up of 45 months. No EDS patients were lost to follow-up or excluded from analysis. The mean improvement in mHHS from preoperatively to postoperatively was 42.9 points, and there were no iatrogenic dislocations. One patient underwent further revision arthroscopy for recurrent pain, subjective giving way, and capsular laxity.

CONCLUSIONS

FAI and extreme capsular laxity can be seen in the setting of EDS. Although increased femoral version was common, acetabular dysplasia was not common in our study. Meticulous capsular plication, arthroscopic correction of FAI when present, and labral preservation led to dramatic improvements in outcomes and subjective stability without any iatrogenic dislocations in this potentially challenging patient population.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Corrigendum. Intraoperative fluoroscopic imaging to treat cam deformities: correlation with 3-dimensional computed tomography

Ross JR, Bedi A, Stone RM, Sibilsky Enselman E, Leunig M, Kelly BT, Larson CM. Intraoperative fluoroscopic imaging to treat cam deformities: correlation with 3-dimensional computed tomography. Am J Sports Med. 2014;42(6):1370-1376. (Original DOI: 10.1177/0363546514529515 )

The Hyperflexible Hip: Managing Hip Pain in the Dancer and Gymnast

Context:

Dance, gymnastics, figure skating, and competitive cheerleading require a high degree of hip range of motion. Athletes who participate in these sports use their hips in a mechanically complex manner.

Evidence Acquisition:

A search of the entire PubMed database (through December 2013) and additional searches of the reference lists of pertinent articles.

Study Design:

Systematic review.

Level of Evidence:

Level 3.

Results:

Whether innate or acquired, dancers and gymnasts have some hypermobility that allows their hips to be placed in potentially impinging or unstable positions required for their given activity. Such extremes of motion can result in both intra-articular and extra-articular impingement as well as compensatory osseous and muscular pathology. In addition, dancers and gymnasts are susceptible to impingement-induced instability. Dancers with innate generalized hyperlaxity are at increased risk of injury because of their activities and may require longer recovery times to return to play. Both nonoperative and operative treatments (arthroscopic and open) have an important role in returning flexibility athletes to their preoperative levels of sport and dance.

Conclusion:

Because of the extreme hip motion required and the compensatory soft tissue laxity in dancers and gymnasts, these athletes may develop instability, impingement, or combinations of both. This frequently occurs in the setting of subtle pathoanatomy or in patients with normal bony anatomy. With appropriate surgical indications and the correct operative technique, the treating surgeon can anticipate high levels of return to play for the gymnast and dancer with hip pain.

Characterization of symptomatic hip impingement in butterfly ice hockey goalies

PURPOSE

This study aimed to characterize the radiographic deformity observed in a consecutive series of butterfly goalies with symptomatic mechanical hip pain and to use computer-based software analysis to identify the location of impingement and terminal range of motion. We also compared these analyses to a matched group of positional hockey players with symptomatic femoroacetabular impingement (FAI).

METHODS

A consecutive series of 68 hips in 44 butterfly-style hockey goalies and a matched group of 34 hips in 26 positional hockey players who underwent arthroscopic correction for symptomatic FAI were retrospectively analyzed. Each patient underwent preoperative anteroposterior (AP) and modified Dunn lateral radiographs and computed tomography (CT) of the affected hips. Common FAI measurements were assessed on plain radiographs. Patient-specific, CT-based 3-dimensional (3D) models of the hip joint were developed, and the femoral version, alpha angles at each radial clock face position, and femoral head coverage were calculated. Maximum hip flexion, abduction, internal rotation in 90° flexion (IRF), flexion/adduction/internal rotation (FADIR), and butterfly position were determined, and the areas of bony collision were defined.

RESULTS

Butterfly goalies had an elevated mean alpha angle on both AP (61.3°) and lateral radiographs (63.4°) and a diminished beta angle (26.0°). The mean lateral center-edge angle (LCEA) measured 27.3° and acetabular inclination was 6.1°. A crossover sign was present in 59% of the hips. The maximum alpha angle on the radial reformatted computed tomographic scan was significantly higher among the butterfly goalies (80.9° v 68.6°; P < .0001) and was located in a more lateral position (1:00 o'clock v. 1:45 o'clock; P < .0001) compared with positional players.

CONCLUSIONS

Symptomatic butterfly hockey goalies have a high prevalence of FAI, characterized by a unique femoral cam-type deformity and noted by an elevated alpha angle and loss of offset, which is greater in magnitude and more lateral when compared with that in positional hockey players. Associated acetabular dysplasia is also common among hockey goalies.

LEVEL OF EVIDENCE

Level IV, prognostic case series.

Residual deformity is the most common reason for revision hip arthroscopy: a three-dimensional CT study

BACKGROUND

Previous studies have reported residual deformity to be the most common reason for revision hip arthroscopy. An awareness of the most frequent locations of the residual deformities may be critical to minimize these failures.

QUESTIONS/PURPOSES

The purposes of this study were to (1) define the three-dimensional (3-D) morphology of hips with residual symptoms before revision femoroacetabular impingement (FAI) surgery; (2) determine the limitation in range of motion (ROM) in these patients using dynamic, computer-assisted, 3-D analysis; and (3) compare these measures with a cohort of patients who underwent successful arthroscopic surgery for FAI by a high-volume hip arthroscopist.

METHODS

Between 2008 and 2013, one senior surgeon (BTK) performed revision arthroscopic FAI procedures on patients with residual FAI deformity and symptoms after prior unsuccessful arthroscopic surgery; all of these 47 patients (50 hips) had preoperative CT scans. Mean patient age was 29 ± 9 years (range, 16-52 years). Three-dimensional models of the hips were created to allow measurements of femoral and acetabular morphology and ROM to bony impingement using a validated, computer-based dynamic imaging software. During the same time period, 65 patients with successful primary arthroscopic treatment of FAI by the same surgeon underwent preoperative CT scans for the symptomatic contralateral hip; this group of 65 patients thus fortuitously provided postoperative evaluation of the originally operated hip and served as a control group. A comparison of the virtual correction with the actual correction in the primary successful FAI treatment cohort was performed. Correspondingly, a comparison of the recommended virtual correction with the correction evident at the time of presentation after failed primary surgery in the revision cohort was performed. Analysis was performed by two independent observers (JRR, OA) and a paired t-test was used for comparison of continuous variables, whereas chi-square testing was used for categorical variables with p < 0.05 defined as significant.

RESULTS

Ninety percent (45 of 50) of patients undergoing revision surgery for symptomatic FAI had residual deformities; the mean maximal alpha angle in revision hips was 68° ± 16° and was most often located at 1:15, considering the acetabulum as a clockface and 1 to 5 o'clock as anterior independent of side. Twenty-six percent (13 of 50) of hips had signs of overcoverage with a lateral center-edge angle greater than or equal to 40°. Dynamic analysis revealed mean direct hip flexion of 114° ± 11° to osseous impingement. Internal rotation in 90° of hip flexion and flexion, adduction, internal rotation to osseous contact were 28° ± 12° and 20° ± 10°, respectively, which were less than those in hips that had underwent hip arthroscopy by a high-volume hip arthroscopist (all p < 0.001).

CONCLUSIONS

We found marked radiographic evidence of incomplete correction of deformity in patients with residual symptoms compared with patients with successful results with residual deformity present in the large majority of patients (45 of 50 [90%]) undergoing residual FAI surgery. We recommend careful attention to full 3-D resection of impinging structures.

Avoiding complications and treating failures of arthroscopic femoroacetabular impingement correction

Complications and failures after hip arthroscopy are reported to be relatively uncommon. Because there are no recent comprehensive, prospective studies observing complications and failures after hip arthroscopy, the current rates are unclear. As the number of surgeons performing hip arthroscopy and the number of procedures performed continue to increase, there is the need for an increased awareness of potential adverse events.

Effect of changes in pelvic tilt on range of motion to impingement and radiographic parameters of acetabular morphologic characteristics

BACKGROUND

The current understanding of the effect of dynamic changes in pelvic tilt on the functional acetabular orientation and occurrence of femoroacetabular impingement (FAI) is limited.

PURPOSE

To determine the effect of changes in pelvic tilt on (1) terminal hip range of motion and (2) measurements of acetabular version as assessed on 2- and 3-dimensional imaging.

STUDY DESIGN

Controlled laboratory study.

METHODS

Preoperative pelvic computed tomographic scans of 48 patients (50 hips) who underwent arthroscopic surgery for the treatment of FAI were analyzed. The mean age of the study population was 25.7 years (range, 14-56 years), and 56% were male. Three-dimensional models of the hips were created, allowing manipulation of the pelvic tilt and simulation of hip range of motion to osseous contact. Acetabular version was measured and the presence of the crossover sign, prominent ischial spine sign, and posterior wall sign was recorded on simulated plain radiographs. Measurements of range of motion to bony impingement during (1) hip flexion, (2) internal rotation in 90° of flexion, and (3) internal rotation in 90° of flexion and 15° adduction were performed, and the location of bony contact between the proximal femur and acetabular rim was defined. These measurements were calculated for -10° (posterior), 0° (native), and +10° (anterior) pelvic orientations.

RESULTS

In native tilt, mean cranial acetabular version was 3.3°, while central version averaged 16.2°. Anterior pelvic tilt (10° change) resulted in significant retroversion, with mean decreases in cranial and central version of 5.9° and 5.8°, respectively (P < .0001 for both). Additionally, this resulted in a significantly increased proportion of positive crossover, posterior wall, and prominent ischial spine signs (P < .001 for all). Anterior pelvic tilt (10° change) resulted in a decrease in internal rotation in 90° of flexion of 5.9° (P < .0001) and internal rotation in 90° of flexion and 15° adduction of 8.5° (P < .0001), with a shift in the location of osseous impingement more anteriorly. Posterior pelvic tilt (10° change) resulted in an increase in internal rotation in 90° of flexion of 5.1° (P < .0001) and internal rotation in 90° of flexion and 15° adduction of 7.4° (P < .0001), with a superolateral shift in the location of osseous impingement.

CONCLUSION/CLINICAL RELEVANCE

Dynamic changes in pelvic tilt significantly influence the functional orientation of the acetabulum and must be considered. Dynamic anterior pelvic tilt is predicted to result in earlier occurrence of FAI in the arc of motion, whereas dynamic posterior pelvic tilt results in later occurrence of FAI, which may have implications regarding nonsurgical treatments for FAI.

Arthroscopic Hip Revision Surgery for Residual Femoroacetabular Impingement (FAI): Surgical Outcomes Compared With a Matched Cohort After Primary Arthroscopic FAI Correction

BACKGROUND

There are limited data reporting outcomes after revision arthroscopic surgery for residual femoroacetabular impingement (FAI).

HYPOTHESIS

(1) Revision arthroscopic FAI correction results in improved outcomes, but they are inferior to those of primary arthroscopic FAI correction. (2) Improved postrevision radiographic parameters are predictive of better outcomes.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who underwent arthroscopic hip revision for residual FAI were reviewed. Pathomorphological findings, intraoperative findings, and preoperative and postoperative modified Harris Hip Score (MHHS), Short Form-12 (SF-12), and pain on a visual analog scale (VAS) values were evaluated. Outcomes after revision arthroscopic FAI correction were compared with outcomes of a matched cohort who underwent primary arthroscopic FAI correction.

RESULTS

A total of 79 patients (85 hips) with a mean age of 29.5 years underwent arthroscopic revision FAI correction (mean follow-up, 26 months). The labrum was debrided (27 hips), repaired (49 hips), or reconstructed (7 hips). Two labrums were stable and required no treatment. The results of revision arthroscopic FAI correction were compared with those of 220 age- and sex-matched patients (237 hips) who underwent primary arthroscopic FAI correction (mean follow-up, 23 months). The mean improvement in outcome scores after revision FAI correction was 17.8 (MHHS), 12.5 (SF-12), and 1.4 (VAS) points compared with 23.4 (MHHS), 19.7 (SF-12), and 4.6 (VAS) points after primary arthroscopic FAI correction. The mean improvement was significantly better in the primary cohort compared with the revision cohort (P < .01 for MHHS, SF-12, and VAS values). Good/excellent results were achieved in 81.7% of the primary cohort and 62.7% of the revision cohort (P < .01). Greater postoperative head-neck offset (P = .024), subspine/anterior inferior iliac spine (AIIS) decompression (P = .014), labral repair/reconstruction (P = .009), and capsular plication (P = .032) were significant predictors for better outcomes after revision surgery.

CONCLUSION

Arthroscopic hip revision surgery for residual FAI yielded significantly improved outcome measures, but these were inferior to those after primary arthroscopic FAI corrective surgery. Improved femoral head-neck offset after cam decompression, identification and treatment of subspine/AIIS impingement, labral preservation/reconstruction, and capsular preservation/plication may be paramount to achieve satisfactory outcomes.

Functional Outcomes and Return to Sports After Acute Repair, Chronic Repair, and Allograft Reconstruction for Proximal Hamstring Ruptures

BACKGROUND

There are limited data regarding outcomes and return to sports after surgery for acute versus chronic proximal hamstring ruptures.

HYPOTHESIS

Surgery for chronic proximal hamstring ruptures leads to improved outcomes and return to sports but at a lower level than with acute repair. Proximal hamstring reconstruction with an Achilles allograft for chronic ruptures is successful when direct repair is not possible.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Between 2002 and 2012, a total of 72 patients with a traumatic proximal hamstring rupture (51 acute, 21 chronic) underwent either direct tendon repair with suture anchors (n = 58) or Achilles allograft tendon reconstruction (n = 14). Results from the Single Assessment Numeric Evaluation (SANE) for activities of daily living (ADL) and sports-related activities, Short Form-12 (SF-12), visual analog scale (VAS), and a patient satisfaction questionnaire were obtained.

RESULTS

The mean time to surgery in the chronic group was 441.4 days versus 17.8 days in the acute group. At a mean follow-up of 45 months, patients with chronic tears had inferior sports activity scores (70.2% vs 80.3%, respectively; P = .026) and a trend for decreased ADL scores (86.5% vs 93.3%, respectively; P = .085) compared with those with acute tears. Patients with chronic tears, however, reported significant improvements postoperatively for both sports activity scores (30.3% to 70.2%; P < .01) and ADL scores (56.1% to 86.5%; P < .01). Greater than 5 to 6 cm of retraction in the chronic group was predictive of the need for allograft reconstruction (P = .015) and resulted in ADL and sports activity scores equal to those of chronic repair (P = .507 and P = .904, respectively). There were no significant differences between groups in SF-12, VAS, or patient satisfaction outcomes (mean, 85.2% satisfaction overall).

CONCLUSION

Acute repair was superior to chronic surgery with regard to return to sports. Acute and chronic proximal hamstring repair and allograft reconstruction had favorable results for ADL. For low-demand patients or those with medical comorbidities, delayed repair or reconstruction might be considered with an expected 87% return to normal ADL. For patients who desire to return to sports, acute repair is recommended.

Intraoperative Fluoroscopic Imaging to Treat Cam Deformities: Correlation With 3-Dimensional Computed Tomography

BACKGROUND

In the diagnosis and surgical treatment of cam-type femoroacetabular impingement (FAI), 3-dimensional (3D) imaging is the gold standard for detecting femoral head-neck junction malformations preoperatively. Intraoperative fluoroscopy is used by many surgeons to evaluate and verify adequate correction of the deformity.

PURPOSE

(1) To compare radial reformatted computed tomography (CT) scans with 6 defined intraoperative fluoroscopic views before surgical correction to determine whether fluoroscopy could adequately depict cam deformity, and (2) to define the influence of femoral version on the clock-face location of the maximum cam deformity on these views.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

A consecutive series of 50 hips (48 patients) that underwent arthroscopic treatment for symptomatic FAI by a single surgeon were analyzed. Each patient underwent a CT scan and 6 consistent intraoperative fluoroscopy views: 3 views in hip extension and 3 views in hip flexion of 50°. The alpha angles of each of the fluoroscopic images were compared with the radial reformatted CT using a 3D software program. Femoral version was also defined on CT studies. Statistical analysis was performed using the Student t test, with P < .05 defined as significant.

RESULTS

Fifty-two percent of patients were male, average age 28 years (range, 15-56 years). The maximum mean alpha angle on fluoroscopy was 65° (range, 37°-93°) and was located on the anteroposterior (AP) 30° external rotation (ER) fluoroscopy view. In comparison, the mean CT-derived maximum alpha angle was 67° and was located at 1:15 (P = .57). The mean clock-face positions of each of the fluoroscopy views (standardized to the right hip) were AP 30° internal rotation, 11:45; AP 0° (neutral) rotation, 12:30; AP 30° ER, 1:00; flexion/0° (neutral) rotation, 1:45; flexion/40° ER, 2:15; and flexion/60° ER, 2:45. Increased femoral anteversion (>20°) was associated with a significant change in the location of the maximum alpha angle (1:45 vs 1:15; P = .002).

CONCLUSION

The described 6 fluoroscopic views are very helpful in localization and visualization of the typical cam deformity from 11:45 to 2:45 and can be used to reliably confirm a complete intraoperative resection of cam-type deformity in most patients. These views correlate with preoperative 3D imaging and may be of even greater importance in the absence of preoperative 3D imaging.

Sports hernia/athletic pubalgia: evaluation and management

Context:

Sports hernia/athletic pubalgia has received increasing attention as a source of disability and time lost from athletics. Studies are limited, however, lacking consistent objective criteria for making the diagnosis and assessing outcomes.

Evidence Acquisition:

PubMed database through January 2013 and hand searches of the reference lists of pertinent articles.

Study Design:

Review article.

Level of Evidence:

Level 5.

Results:

Nonsurgical outcomes have not been well reported. Various surgical approaches have return-to–athletic activity rates of >80% regardless of the approach. The variety of procedures and lack of outcomes measures in these studies make it difficult to compare one surgical approach to another. There is increasing evidence that there is an association between range of motion–limiting hip disorders (femoroacetabular impingement) and sports hernia/athletic pubalgia in a subset of athletes. This has added increased complexity to the decision-making process regarding treatment.

Conclusion:

An association between femoroacetabular impingement and athletic pubalgia has been recognized, with better outcomes reported when both are managed concurrently or in a staged manner.

The learning curve for hip arthroscopy: a systematic review

PURPOSE

The learning curve for hip arthroscopy is consistently characterized as "steep." The purpose of this systematic review was to (1) identify the various learning curves reported in the literature, (2) examine the evidence supporting these curves, and (3) determine whether this evidence supports an accepted number of cases needed to achieve proficiency.

METHODS

The electronic databases Embase and Medline were screened for any clinical studies reporting learning curves in hip arthroscopy. Two reviewers conducted a full-text review of eligible studies and a hand search of conference proceedings and reference sections of the included articles. Inclusion/exclusion criteria were applied, and a quality assessment was completed for each included article. Descriptive statistics were compiled.

RESULTS

We identified 6 studies with a total of 1,063 patients. Studies grouped surgical cases into "early" versus "late" in a surgeon's experience, with 30 cases being the most common cutoff used. Most of these studies used descriptive statistics and operative time and complication rates as measures of competence. Five of 6 studies showed improvement in these measures between early and late experience, but only one study proposed a bona fide curve.

CONCLUSIONS

This review shows that when 30 cases was used as the cutoff point to differentiate between early and late cases in a surgeon's experience, there were significant reductions in operative time and complication rates. However, there was insufficient evidence to quantify the learning curve and validate 30, or any number of cases, as the point at which the learning curve plateaus. As a result, this number should be interpreted with caution.

LEVEL OF EVIDENCE

Level IV, systematic review of Level IV studies.

Persistent structural disease is the most common cause of repeat hip preservation surgery

BACKGROUND

Hip preservation surgery has become more commonplace, yet when it fails, it is unclear why it does so. Understanding failed procedures should lead to improved surgical results.

QUESTIONS/PURPOSES

The purposes of this study were to (1) characterize patients undergoing hip preservation surgery after prior procedures; (2) compare demographics, hip pain, and function in patients with prior procedures with those undergoing primary surgery; (3) determine the types of previous procedures and the reasons for secondary surgery; and (4) report the procedure profile of the secondary surgeries.

METHODS

A prospective, multicenter hip preservation database of 2263 patients (2386 surgery cases) was reviewed to identify 352 patients (359 hips, 15% of the total) who had prior surgery. Patient demographics, type of previous surgery, diagnostic categories, clinical scores, and type of secondary procedure were recorded.

RESULTS

For patients undergoing secondary surgery, the average age was 23 years and 70% were female. Hip pain and function were similar between patients undergoing primary and secondary surgery. The previous surgical approaches were open in 52% and hip arthroscopy in 48%. In the femoroacetabular impingement and adult acetabular dysplasia subgroups, hip arthroscopy was the most common previous surgical approach (86% and 64%, respectively). Inadequately corrected structural disease was the most common reason for secondary surgery. Femoral osteochondroplasty and acetabular reorientation were the most common secondary procedures.

CONCLUSIONS

Inadequately corrected structural disease (femoroacetabular impingement or acetabular dysplasia) was commonly associated with the need for secondary hip preservation surgery. Although we do not have data to identify other technical failures, the available data suggest primary treatments should encompass comprehensive deformity correction when indicated.

Anatomic footprint of the direct head of the rectus femoris origin: cadaveric study and clinical series of hips after arthroscopic anterior inferior iliac spine/subspine decompression

PURPOSE

The purposes of this study were to define the anatomy of the anterior inferior iliac spine (AIIS) and its relation to the footprint of the rectus femoris tendon and to evaluate on the clinical outcomes after AIIS/subspine decompression.

METHODS

The rectus origin was dissected and detached in 11 male cadaveric hips with a mean age of 54.3 ± 14.3 years (range, 33 to 74 years). The proximal-distal and medial-lateral extent of the footprint and its relation to the AIIS and acetabular rim were evaluated, with the 12-o'clock position defined as directly lateral at the insertion of the indirect head of the rectus tendon and the 1- to 6-o'clock positions defined as anterior acetabular positions. To assess the safety and efficacy of subspine decompression for AIIS deformity, clinical correlation of a series of 163 AIIS decompressions (mean age, 27.8 years; age range, 14 to 52 years) performed from January 2011 to January 2012 was completed, and outcome scores, strength deficits, and ruptures were assessed by manual muscle testing and postoperative radiographs. All patients presented with symptomatic FAI with proximal femoral and/or acetabular deformity and type 2 (131 hips) or type 3 (32 hips) AIIS morphology as defined by Hetsroni et al.

RESULTS

The mean proximal-distal and medial-lateral distances for the rectus origin footprint were 2.2 ± 0.1 cm (range, 2.1 to 2.4 cm) and 1.6 ± 0.3 cm (range, 1.2 to 2.3 cm), respectively. There was a characteristic bare area at the anteromedial AIIS. On the clock face, the lateral margin (1-o'clock to 1:30 position) and medial margin (2-o'clock to 2:30 position) of the AIIS and the indirect head of the rectus (12 o'clock) were consistent for all specimens. In the clinical series, 163 AIIS decompressions were performed for symptomatic subspine impingement. The mean modified Harris Hip Score was 63.1 points (range, 21 to 90 points) preoperatively compared with 85.3 points (range, 37 to 100 points) at a mean follow-up of 11.1 ± 4.1 months (range, 6 to 24 months) (P < .01). Short Form 12 scores improved significantly from a mean of 70.4 (range, 34 to 93) preoperatively to a mean of 81.3 (range, 31 to 99) postoperatively (P < .01). The mean pain score on a visual analog scale also improved significantly from a mean of 4.9 (range, 0.1 to 8.6) preoperatively to a mean of 1.9 (range, 0 to 7.8) postoperatively (P < .01). The mean alpha angle improved from 61.5° (range, 35° to 90°) preoperatively to 49° (range, 35° to 63°) postoperatively on anteroposterior radiographs and from 71° (range, 45° to 90°) preoperatively to 44.3° (range, 37° to 60°) postoperatively on lateral radiographs. No short- or long-term hip flexion deficits or rectus femoris avulsions were noted with up to 2 years' follow-up.

CONCLUSIONS

The origin of the rectus femoris tendon is broad on the AIIS and protective against direct head detachment with subspine decompression. This broad origin and consistent bare area anteromedially on the AIIS can be readily used by surgeons to perform a safe AIIS resection in cases of symptomatic impingement. Arthroscopic subspine decompression in addition to osteoplasty for symptomatic cam- and/or pincer-type FAI deformities can reliably improve outcome scores without significant hip flexion deficits or AIIS/rectus femoris avulsions.

CLINICAL RELEVANCE

The direct head of the rectus tendon has a broad insertion on the AIIS, and an area devoid of tendon provides a "safe zone" for subspine decompression in cases of symptomatic AIIS impingement.

Elevation in circulating biomarkers of cartilage damage and inflammation in athletes with femoroacetabular impingement

BACKGROUND

Femoroacetabular impingement (FAI) is one of the most common causes of early cartilage and labral damage in the nondysplastic hip. Biomarkers of cartilage degradation and inflammation are associated with osteoarthritis. It was not known whether patients with FAI have elevated levels of biomarkers of cartilage degradation and inflammation.

HYPOTHESIS

Compared with athletes without FAI, athletes with FAI would have elevated levels of the inflammatory C-reactive protein (CRP) and cartilage oligomeric matrix protein (COMP), a cartilage degradation marker.

STUDY DESIGN

Controlled laboratory study.

METHODS

Male athletes with radiographically confirmed FAI (n = 10) were compared with male athletes with radiographically normal hips with no evidence of FAI or hip dysplasia (n = 19). Plasma levels of COMP and CRP were measured, and subjects also completed the Short Form-12 (SF-12) and Hip Disability and Osteoarthritis Outcome Score (HOOS) surveys.

RESULTS

Compared with controls, athletes with FAI had a 24% increase in COMP levels and a 276% increase in CRP levels as well as a 22% decrease in SF-12 physical component scores and decreases in all of the HOOS subscale scores.

CONCLUSION

Athletes with FAI demonstrate early biochemical signs of increased cartilage turnover and systemic inflammation.

CLINICAL RELEVANCE

Chondral injury secondary to the repetitive microtrauma of FAI might be reliably detected with biomarkers. In the future, these biomarkers might be used as screening tools to identify at-risk patients and assess the efficacy of therapeutic interventions such as hip preservation surgery in altering the natural history and progression to osteoarthritis.

The approach to the evaluation and surgical treatment of mechanical hip pain in the young patient: AAOS exhibit selection

The mechanical causes of hip pain in a young athlete often reflect a complex combination of static and dynamic factors. A comprehensive diagnostic approach is paramount to the development of a rational treatment strategy that will address all underlying pathologic factors. The goals of this paper are to highlight the pertinent biomechanical factors of the hip joint in femoroacetabular impingement and to discuss the clinical history, physical examination, and radiographic findings that are essential to formulating a proper diagnosis and an effective treatment plan. In addition, the current literature and reported outcomes of femoroacetabular impingement surgery in athletic patients are reviewed.

Current concepts and trends for operative treatment of FAI: hip arthroscopy

There has been an increasing body of literature regarding arthroscopic management of femoroacetabular impingement (FAI). Refinement of arthroscopic techniques has allowed for more complete management of FAI, and meta-analysis and systematic reviews have shown comparable outcomes to surgical hip dislocation with appropriate indications. There are still, however, pathomorphologies that are not accessible or much more challenging to address arthroscopically, and open corrective procedures should be considered in these situations. Extra-articular FAI is receiving increased attention and can be secondary to anterior inferior iliac spine/subspine impingement, trochanteric-pelvic impingement, and ischio-femoral impingement. Femoral and acetabular version and their impact on hip stability as well as the concept of impingement induced instability are being increasingly recognized. Acetabular labral and capsular management and repair techniques have also received increased attention. Finally, 3-dimensional imaging and dynamic software analysis are beginning to emerge as potential tools to better evaluate hip pathomorphology.

Anterior inferior iliac spine morphology correlates with hip range of motion: a classification system and dynamic model

BACKGROUND

The anterior inferior iliac spine (AIIS) contributes to hip dysfunction in patients with symptomatic impingement and resection of a prominent AIIS can reportedly improve function. However, the variability of the AIIS morphology and whether that variability correlates with risk of associated symptomatic impingement are unclear.

QUESTIONS/PURPOSES

We characterized AIIS morphology in patients with hip impingement and tested the association between specific AIIS variants and hip range of motion.

METHODS

We evaluated three-dimensional CT reconstructions of 53 hips (53 patients) with impingement and defined three morphological AIIS variants: Type I when there was a smooth ilium wall between the AIIS and the acetabular rim, Type II when the AIIS extended to the level of the rim, and Type III when the AIIS extended distally to the acetabular rim. A separate cohort of 78 hips (78 patients) with impingement was used to compare hip range of motion among the three AIIS types.

RESULTS

Mean hip flexion was limited to 120°, 107°, and 93° in hips with Type I, Type II, and Type III AIIS, respectively. Mean internal rotation was limited to 21°, 11°, and 8° in hips with Type I, Type II, and Type III AIIS, respectively.

CONCLUSIONS

When the AIIS is classified into three variants based on the relationship between the AIIS and the acetabular rim in patients with impingement, Type II and III variants are associated with a decrease in hip flexion and internal rotation, supporting the rationale for considering AIIS decompression for variants that extend to and below the rim.

Novel CT-based three-dimensional software improves the characterization of cam morphology

BACKGROUND

Incomplete correction of femoral offset and sphericity remains the leading cause for revision surgery for symptomatic femoroacetabular impingement (FAI). Because arthroscopic exploration is technically difficult, a detailed preoperative understanding of morphology is of paramount importance for preoperative decision-making.

QUESTIONS/PURPOSES

The purposes of this study were to (1) characterize the size and location of peak cam deformity with a prototype CT-based software program; (2) compare software alpha angles with those obtained by plain radiograph and CT images; and (3) assess whether differences can be explained by variable measurement locations.

METHODS

We retrospectively reviewed the preoperative plain radiographs and CT scans of 100 symptomatic cam lesions treated by arthroscopy; recorded alpha angle and clockface measurement location with a novel prototype CT-based software program, CT, and Dunn lateral plain radiographs; and used ordinary least squares regressions to assess the relationship between alpha angle and measurement location.

RESULTS

The software determined a mean alpha angle of 70.8° at 1:23 o'clock and identified 60% of maximum alpha angles between 12:45 and 1:45. The CT and plain radiographs underestimated by 5.7° and 8.2°, respectively. The software-based location was anterosuperior to the mean CT and plain radiograph measurement locations by 41 and 97 minutes, respectively. Regression analysis confirmed a correlation between alpha angle differences and variable measurement locations.

CONCLUSIONS

Software-based three-dimensional (3-D) imaging generated alpha angles larger than those found by plain radiograph and CT, and these differences were the result of location of measurement. An automated 3-D assessment that accurately describes the location and topography of FAI may be needed to adequately characterize preoperative deformity.

Remembering our roots: eponyms in sports medicine

For as long as athletes have been competing, injuries from competition have resulted. Sports medicine has a rich and storied history with significant contributors from many different countries and civilizations. Over time, we have honored the contributions of important figures in sports medicine with the use of eponyms. However, the continued use of eponyms in medicine has been called into question by a number of authors. They cite inaccuracies in definition and context, lack of descriptive value, and the possible celebration of unsavory characters. However, eponyms are pervasive in the medical literature. They bring color and character and allow us to honor those who came before us. Furthermore, eponyms can hide some distressing aspects of a disease. This review of eponyms in sports medicine provides an opportunity to celebrate our predecessors, recognize the international flavor of sports medicine, and promote accurate use of eponyms for the future.