Acetabular Labral Reconstruction Does Not Demonstrate Superior Biomechanical Properties Compared to Labral Repair or Intact Native Labrum but Is Superior to Labral Excision: A Systematic Review of Cadaveric Studies.

PURPOSE: To systematically review and compare biomechanical properties of labral reconstruction to labral repair, intact native labrum, and labral excision in cadaveric studies. METHODS: A search of the PubMed and Embase databases was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and checklist. Cadaveric studies focused on hip biomechanics related to intact labrum, labral repair, labral reconstruction, labral augmentation, and labral excision were included. Investigated parameters included biomechanical data measures, such as distraction force, distance to suction seal rupture, peak negative pressure, contact area, and fluid efflux. Review articles, duplicates, technique reports, case reports, opinion articles, articles written in a language other than English, clinical studies focusing on patient-reported outcomes, studies performed in animals, and articles with no abstract available were also excluded. RESULTS: Fourteen cadaveric biomechanical studies were included that compared labral reconstruction to labral repair (4 studies), labral reconstruction to labral excision (4 studies); and evaluation of distractive force of the labrum (3 studies), the distance to suction seal rupture (3 studies), fluid dynamics (2 studies), displacement at peak force (1 study), and stability ratio (1 study). Data pooling was not performed because of methodological heterogenicity of the studies. Labral reconstruction did not outperform labral repair in restoring the hip suction seal or any other biomechanical property. Labral repair significantly prevented greater fluid efflux when compared to labral reconstruction. Labral repair and reconstruction improved the distractive stability of the hip fluid seal from the labral tear and labral excision stage, respectively. Furthermore, labral reconstruction demonstrated to have better biomechanical properties than labral excision. CONCLUSIONS: In cadaveric studies, labral repair or intact native labrum was biomechanically more superior than labral reconstruction; however, labral reconstruction can restore acetabular labral biomechanical properties and was biomechanically superior to labral excision. CLINICAL RELEVANCE: In cadaveric models, labral repair outperforms segmental labral reconstruction in preserving the hip suction seal; nonetheless, segmental labral reconstruction biomechanically outperforms labral excision at time 0.

Can the Acetabular Labrum Be Reconstructed With a Meniscal Allograft? An In Vivo Pig Model.

BACKGROUND: No single graft type has been shown to have a benefit in acetabular labral reconstruction. The native labrum and lateral meniscus share many similarities, suggesting that the meniscus may be a promising source of graft material in labral reconstruction. QUESTIONS/PURPOSES: Using a pig model, we sought to evaluate the healing process of fresh-frozen meniscus allograft for acetabular reconstruction by assessing (1) MRI and macroscopic observations of the meniscus allograft; (2) histologic appearance and immunohistologic evaluation of the meniscus allograft, native meniscus, and labrum; (3) microscopic assessment of the native labrum and meniscus via scanning electron microscopy; and (4) biomechanical assessment of tensile properties. METHODS: Twelve skeletally mature male miniature Bama pigs (24 hips) were randomly divided into two groups: labral defect group (control) and lateral meniscus allograft group. The selection of Bama pig specimens was based on the similarity of their acetabular labrum to that of the human acetabular labrum, characterized by the presence of fibrocartilage-like tissue lacking blood vessels. The pigs underwent bilateral hip surgery. Briefly, a 1.5-cm-long section was resected in the anterior dorsal labrum, which was left untreated or reconstructed using an allogeneic lateral meniscus. The pigs were euthanized at 12 and 24 weeks postoperatively, and then evaluated by macroscopic observations and MRI measurement to assess the extent of coverage of the labral defect. We also performed a histologic analysis and immunohistologic evaluation to assess the composition and structure of meniscus allograft, native labrum, and meniscus, as well as scanning electron microscopy assessment of the microstructure of the native labrum and meniscus and biomechanical assessment of tensile properties. RESULTS: Imaging measurement and macroscopic observations revealed that the resected area of the labrum was fully filled in the lateral meniscus allograft group, whereas in the control group, the labral defect remained at 24 weeks. The macroscopic scores of the meniscus allograft group (8.2 ± 0.8) were higher than those of the control groups (4.8 ± 1.0) (mean difference 3.3 [95% CI 1.6 to 5.0]; p < 0.001). Moreover, in the meniscus allograft group, histologic assessment identified fibrocartilage-like cell cluster formation at the interface between the graft and acetabulum; cells and fibers arranged perpendicularly to the acetabulum and tideline structure that were similar to those of native labrum could be observed at 24 weeks. Immunohistochemical results showed that the average optical density value of Type II collagen at the graft-acetabulum interface was increased in the meniscus allograft group at 24 weeks compared with at 12 weeks (0.259 ± 0.031 versus 0.228 ± 0.023, mean difference 0.032 [95% CI 0.003 to 0.061]; p = 0.013). Furthermore, the tensile modulus of the lateral meniscus allograft was near that of the native labrum at 24 weeks (54.7 ± 9.9 MPa versus 63.2 ± 11.3 MPa, mean difference -8.4 MPa [95% CI -38.3 to 21.4]; p = 0.212). CONCLUSION: In a pig model, lateral meniscus allografts fully filled labral defects in labral reconstruction. Regeneration of a fibrocartilage transition zone at the graft-acetabulum interface was observed at 24 weeks. CLINICAL RELEVANCE: The use of an autograft meniscus for labral reconstruction may be a viable option when labral tears are deemed irreparable. Before its clinical implementation, it is imperative to conduct a comparative study involving tendon grafts, which are extensively used in current clinical practice.

Review of K.H. Pridie (1959) on "A method of resurfacing osteoarthritic knee joints".

This classic discusses the original publication "A method of resurfacing osteoarthritic knee joints" by Dr K.H. Pridie (1959), where this pioneer surgeon described a newly developed method for the treatment of osteoarthritic joint surfaces of the knee, which he named subchondral drilling. This short and concise 11-line publication appeared in the Proceedings of the Congress of the British Orthopaedic Association. It has generated 464 citations since 1959, becoming part of the hundred most-cited publications in knee research. Pridie introduced in clinical experimentation the entity of Marrow Stimulation Techniques to liberate mesenchymal stem cells from cancellous bone. He was aware that the results induced, in terms of quality of the regrown tissue, was limited and "only" fibrocartilage. His idea might have been raised from the work of numerous animal researchers who confirmed repeatedly since 1905 that cartilage needed an osseous perforation to heal. Although the past 60 years brought modifications from the technique described in the original article, the concept of marrow stimulation introduced by Pridie remains the most frequently used in cartilage repair surgery today.

Acetabular Labral Reconstruction with Iliotibial Band Autograft: Outcome and Survivorship at a Minimum 10-Year Follow-up.

BACKGROUND: Labral reconstruction has been shown to result in improved patient-reported outcomes (PROs) at mid-term follow-up in patients with a deficient labrum. The purpose of this study was to determine survivorship and PROs at a minimum 10-year follow-up. METHODS: A retrospective evaluation of a prospectively collected single-surgeon database included 91 hips (89 patients) that underwent arthroscopic labral reconstruction with iliotibial band autograft between 2006 and 2008. The primary PRO was the Hip Outcome Score (HOS)-activities of daily living (ADL). The modified Harris hip score (mHHS), HOS-sports, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and patient satisfaction (on a scale of 1 to 10) were also collected at a 10-year minimum follow-up. Survivorship analysis curves were evaluated. RESULTS: Eighty-two hips were evaluated at a 10-year minimum follow-up. Overall survivorship, with revision hip arthroscopy or total hip arthroplasty (THA) as the end point, was 70% at 5 years and 61% at 10 years, and the mean survival time was 9 years (95% confidence interval = 7.6 to 10 years). For the patients who did not undergo subsequent surgery, on average the mHHS increased from 60 preoperatively to 82 at the 10-year follow-up (p = 0.001), the HOS-ADL improved from 69 to 90 (p = 0.004), the HOS-sports improved from 43 to 76 (p = 0.001), and the median patient satisfaction was 10 of 10. Eighty percent of the patients achieved the minimal clinically important difference (MCID) in the HOS-ADL, and 87% obtained a patient acceptable symptom state (PASS). CONCLUSIONS: Following arthroscopic labral reconstruction with iliotibial band autograft, 9% of the hips underwent revision arthroscopy and 27% underwent THA. At 10 years, the survival rate, with revision hip arthroscopy or THA as the end point, was 61%; however, for those with >2 mm of joint space, the current indication for labral reconstruction, the 10-year survival rate was 90%. Excellent PROs and patient satisfaction were reported by those who did not require revision or THA. With appropriate patient selection and prevention of postoperative adhesions, labral reconstruction results in excellent outcomes and high patient satisfaction that is sustained at a minimum 10-year follow-up. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Comparison of Suction Seal and Contact Pressures Between 270° Labral Reconstruction, Labral Repair, and the Intact Labrum.

PURPOSE: To biomechanically compare the suction seal, contact area, contact pressures, and peak forces of the intact native labrum, torn labrum, 12- to 3-o'clock labral repair, and 270° labral reconstruction in the hip. METHODS: A cadaveric study was performed using 8 fresh-frozen hemipelvises with intact labra and without osteoarthritis. Intra-articular pressure maps were produced for each specimen using an electromechanical testing system under the following conditions: (1) intact labrum, (2) labral tear, (3) labral repair between the 12- and 3-o'clock positions, and (4) 270° labral reconstruction using iliotibial band allograft. Specimens were examined in neutral position, 20° of extension, and 60° of flexion. In each condition, contact pressure, contact area, and peak force were obtained. Repeated-measures analysis of variance was used to identify differences in biomechanical parameters among the 3 conditions. Qualitative differences in suction seal were compared between labral repair and labral reconstruction using the Fisher exact test. RESULTS: Repeated-measures analysis of variance for contact area in neutral position, extension, and flexion showed statistically significant differences between the normalized study states (P < .05). Post hoc analysis showed significantly larger contact areas measured in labral repair specimens than in labral reconstruction specimens in the extension and flexion positions. Region-of-interest analysis for the normalized contact area in the extension and flexion positions, as well as normalized contact pressures in neutral position, showed statistically significant differences between the labral states (P < .05). Finally, 8 labral repairs (100%) versus only 1 labral reconstruction (12.5%) retained the manually tested suction seal (P < .001). CONCLUSIONS: In this in vitro biomechanical model, 270° labral reconstruction resulted in decreased intra-articular contact area and loss of suction seal when compared with labral repair. Clinically, labral reconstruction may not restore the biomechanical characteristics of the native labrum as compared with labral repair. CLINICAL RELEVANCE: Labral reconstruction may result in lower intra-articular hip contact area and loss of suction seal, affecting the native biomechanical function of the acetabular labrum. Further biomechanical studies and clinical studies are necessary to determine whether there are any long-term consequences of 270° labral reconstruction.

Arthroscopic labral debridement versus labral repair for patients with femoroacetabular impingement: A meta-analysis.

OBJECTIVE: Femoroacetabular impingement (FAI) is a common cause of hip pain and even tearing of the acetabular labrum in young adults and athletes. Either arthroscopic labral debridement (LD) or labral repair (LR) technique for FAI patients is needed to choose. We conducted this systematic review and meta-analysis to compare the clinical outcomes of arthroscopic LD versus LR intervention. METHODS: The five studies were acquired from PubMed, Medline, Embase, and Cochrane Library. The data were extracted by two of the coauthors independently and were analyzed by RevMan5.3. Mean differences (MDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Cochrane Collaboration's Risk of Bias Tool and Newcastle-Ottawa Scale were used to assess risk of bias. RESULTS: Four observational studies and one prospective randomized study were assessed. The methodological quality of the trials indicated a low to moderate risk of bias. The pooled results of Non-Arthritic Hip Score (NAHS), failure rate of surgeries and complications showed that the differences were not statistically significant between the two interventions. The difference of modified Harris Hip Score (mHHS), the Visual Analogue Scale (VAS) score and satisfaction rate was statistically significant between LD and LR intervention, and LR treatment was more effective. Sensitivity analysis proved the stability of the pooled results and there were too less included articles to verify the publication bias. CONCLUSIONS: Hip arthroscopy with either LR or LD is an effective treatment for symptomatic FAI. The difference of mHHS, VAS score, and satisfaction rate was statistically significant between LD and LR intervention, and arthroscopic LR could re-create suction-seal effect, potentially reduce microinstability, which demonstrated a trend toward better clinical efficacy and comparable safety compared with LD. The arthroscopic LR technique is recommended as the optical choice for acetabular labrum tear with FAI.

Morphology of Spring Ligament Fibrocartilage Complex Lesions.

BACKGROUND: The spring ligament fibrocartilage complex (SLFC) is an important static foot stabilizer comprising the superomedial ligament (SML) and the inferior ligament, with anatomical variations (third ligament). The aim of this study was to describe the patterns of the lesions found during SLFC surgery, to allow direct comparison between the results with various surgical techniques. METHODS: Fourteen consecutive patients with SLFC lesions were analyzed during surgical treatment. The mean patient age was 37.3 years, and the mean time from injury was 6.9 months. Intraoperative assessments and anatomical descriptions of the lesions were collected. RESULTS: Three types of lesion were found. In 13 of 14 cases, only the superomedial ligament was involved: five superomedial ligament distentions and eight superomedial ligament ruptures. In one case, total SLFC (superomedial and inferior ligaments) rupture was observed. CONCLUSIONS: The first classification of SLFC lesions is presented, which is simple, consistent, and based on anatomical description.

The Diagnostic Value of Ultrasound in Anterosuperior Acetabular Labral Tear.

PURPOSE: To investigate diagnostic value of ultrasound in acetabular labral tears compared with magnetic resonance (MR) imaging, using arthroscopic surgery as the gold standard in a relatively large sample size. METHODS: We retrospectively evaluated patients who attended the sports medicine clinic of our department and underwent arthroscopic surgery for the diagnosis of an anterosuperior acetabular labral tear between June 2014 and April 2018. All the patients received hip joint ultrasound examination and MR imaging evaluation before arthroscopic surgery. The sensitivity, specificity, and accuracy of ultrasound and MR imaging were calculated and compared. RESULTS: A total of 195 patients were enrolled in this study. Of these, 184 had arthroscopically confirmed anterosuperior acetabular labral tear. The sensitivity, specificity, positive predictive value (PPV), negative predictive value, and accuracy by ultrasound were, respectively, 68.5%, 81.8%, 98 4%, 13.4%, and 69.2%, retrospectively. For MR imaging, the sensitivity, specificity, PPV, negative predictive value, and accuracy were 84.8%, 63.6%, 97.5%, 20.0%, and 83.6%, respectively. CONCLUSIONS: Although ultrasound had a slightly lower sensitivity for detecting anterosuperior acetabular labral tear, it had a higher specificity and PPV than MR imaging. With the advantages of being inexpensive, relatively quick, noninvasive, and having dynamic evaluation, ultrasound could be used as a feasible method to evaluate anterosuperior acetabular labral tear. LEVEL OF EVIDENCE: Level IV, case series.

Clinical Outcomes and Factors Influencing These Outcome Measures Resulting in Success After Arthroscopic Transosseous Triangular Fibrocartilage Complex Foveal Repair.

PURPOSE: To analyze postoperative outcomes after arthroscopic transosseous triangular fibrocartilage complex (TFCC) foveal repair and identify factors affecting the clinical outcomes. METHODS: This study retrospectively enrolled patients who were treated for TFCC foveal tears by arthroscopic transosseous TFCC foveal repair. The diagnosis of TFCC foveal tear was made based on medical history, physical examination, and magnetic resonance imaging, with confirmation via arthroscopic examination. Outcome evaluation was completed at a minimum of 2 years postoperatively, and patients were classified into 2 groups according to the minimal clinically important difference of the Patient-Rated Wrist Evaluation. Various factors including age, sex, trauma history, body mass index, symptom duration, hand dominance, ulnar variance, subluxation of the distal radioulnar joint, preoperative pain score, and functional status, as well as the cross-sectional area (CSA) of the pronator quadratus (PQ) muscle, were retrospectively analyzed using both univariate and multivariate analyses. RESULTS: During the study period, 42 patients were treated for TFCC foveal tears. The functional status significantly improved after surgery. Overall, 27 and 15 patients showed good and poor functional outcomes, respectively, which were assessed according to the minimal clinically important difference of the Patient-Rated Wrist Evaluation. On univariate analysis, clinical outcomes were better in male patients (P = .035), younger patients (P = .022), and those with higher CSAs of the PQ muscles (P < .001). However, on multivariable logistic regression analysis, only a higher CSA of the PQ muscle was identified as an independent prognostic factor affecting clinical outcome after TFCC foveal repair (P = .004). CONCLUSION: Arthroscopic transosseous TFCC complex foveal repair led to satisfactory results. However, lower PQ muscle CSA on magnetic resonance imaging was the most independent prognostic factor negatively affecting clinical outcomes. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Additional Dorsal Fibrocartilage Repair in a Combined Radial Collateral Ligament and Dorsal Fibrocartilage Injury of the Thumb Metacarpophalangeal Joint.

The purpose of this study was to evaluate the necessity of an additional dorsal fibrocartilage (DFC) repair in combined radial collateral ligament (RCL) and DFC injuries of the thumb metacarpophalangeal joint (MPJ). Eight cadaveric thumbs were used. Ulnar/radial deviation, prosupination, and volar/dorsal laxity were measured. Serial sectioning was performed of the RCL and the DFC. The RCL followed by the DFC were then reattached sequentially. Measurements were performed for intact, RCL cut, RCL+DFC cut, RCL repair alone, and RCL+DFC repair. The neutral position shifted ulnarly, pronated, and subluxed volarly after RCL+DFC cut. Volar subluxation was reduced with RCL+DFC repair compared with RCL repair alone. With external loading, ulnar deviation, pronation, and volar laxity increased significantly after RCL+DFC cut. Ulnar deviation reduced significantly with RCL+DFC repair (12.4°, 10.8°, and 10.9°) compared with RCL repair alone (14.4°, 14.3°, and 18.9°) at 0°, 30°, and 60°, respectively. Pronation reduced significantly with RCL+DFC repair (7.1° and 9.4°) compared with RCL repair alone (10.2° and 12.6°) at 0° and 30°, respectively. Volar subluxation reduced significantly with RCL+DFC repair (0.9 mm and 1.2 mm) compared with RCL repair alone (2.1 mm and 1.8 mm) at 30°and 60°, respectively. Radial collateral ligament repair alone does not restore anatomic dorsoradial stability of the thumb MPJ in a combined RCL and DFC injury. Combined repair of the RCL and the DFC is recommended to reduce the MPJ to its native position and minimize postoperative laxity. [Orthopedics. 2019; 42(2):e268-e272.].

The Extension-Thickness-Damage (ETD) score: a pre-operative hip MR arthrography-based classification to predict type of labrum surgery.

INTRODUCTION: Hip magnetic resonance arthrography (MRA) is the pre-operative imaging modality of choice in patients with labral damage, with several classifications of labral tears having been reported based on MRA findings. Nevertheless, none of the available classification systems allows the surgeon to predict before surgery how a labral tear could be treated. Our purpose was to develop a new MRA-based scoring system of labral tears to predict before surgery the treatment option more suitable for labral tears. MATERIALS AND METHODS: Forty-seven patients (29 males and 18 females; mean age: 35.9 ± 12.4) performed hip MRA for suspicious of femoroacetabular impingement and were afterwards subjected to arthroscopic treatment. Two musculoskeletal radiologists reviewed all pre-operative examinations and provided the Extension-Thickness-Damage score for each patient, based on Extension of tear, Thickness of labrum, and type of Damage. Chondral lesions grading was based on the arthroscopic findings according to Konan classification. For statistical purposes, patients were divided into two groups, depending on the type of treatment: labral repair or debridement. Mann-Whitney U, Chi-square, receiver operator curves, and Cohen kappa statistics were used. RESULTS: 35/47 underwent repair, while 12/47 were debrided. In both groups, the median chondral damage was grade III, with no significant differences (p = 0.439). The median Extension-Thickness-Damage score in the repair group (6) was significantly lower (p < 0.001) than that in the debridement group (8). The highest diagnostic performance (area under the curve) of Extension-Thickness-Damage was 0.819. The inter-observer agreement was substantial in the evaluation of Extension (k = 0.626) and Thickness (k = 0.771), and almost perfect for Damage (k = 0.827). Higher scores of Extension and Thickness were more frequently associated with debridement (p < 0.001; p = 0.0016, respectively), with no significant differences on the basis of Damage parameter (p = 0.284). CONCLUSIONS: The MRA-based Extension-Thickness-Damage score could represent a helpful pre-operative tool, expressing the extent of the damage and its reparability before arthroscopy.

Arthroscopic Reconstruction of the Irreparable Acetabular Labrum: A Match-controlled Study.

PURPOSE: To report clinical outcomes of arthroscopic labral reconstruction in the hip at minimum 2-year follow-up in comparison to a pair-matched labral repair group. METHODS: Patients were included in this study if they underwent labral reconstruction during hip arthroscopy and had minimum 2-year follow-up data available. Exclusion criteria were active workers' compensation claims or previous ipsilateral hip surgery or conditions. Reconstruction patients were matched 1:2 to patients that underwent arthroscopic labral repair but otherwise met all inclusion and exclusion criteria. Matching criteria were age within 5 years, sex, body mass index within 5, same capsular treatment, and whether there was chondral damage of Outerbridge grade II or greater. Three patient-reported outcome (PRO) measures and visual analog scale (VAS) for pain were recorded preoperatively and at a minimum of 2 years postoperatively. International Hip Outcome Tool and patient satisfaction were also collected at latest follow-up. RESULTS: Thirty-four reconstruction patients were matched to 68 repair patients. There were no significant differences in age (P = .941), sex (P > .999), body mass index (P = .935), or any other demographics between groups. A statistically significant increase was seen in PROs for both the reconstruction group (Modified Harris Hip Score, P = .002; Hip Outcome Score - Sports Subscale, P<.001; Non-arthritic Hip Score, P<.001) and the repair group (Modified Harris Hip Score, P<.001; Hip Outcome Score - Sports Subscale, P < .001; Non-arthritic Hip Score, P<.001) at minimum 2-year follow-up. Significant decrease was shown for VAS for both groups (reconstruction VAS, P<.001; repair, P<.001) at minimum 2-year follow-up. There were no significant differences in rates of postoperative complications (P>.999), secondary arthroscopy (P>.999), or conversion to total hip arthroplasty (P = .728) between groups. CONCLUSIONS: Arthroscopic labral reconstruction is associated with significant improvement in PROs and a low incidence of secondary surgery within 2-year follow-up. Improvements in PROs, VAS, patient satisfaction, and incidence of secondary procedures were comparable to a match control treated with labral repair. Although there were no differences shown in the 2 groups with respect to complication rate, secondary arthroscopy, or conversion to total hip arthroplasty, the study was not powered to compare these outcome parameters. Based on this evidence, either labral repair or reconstruction may be selected depending upon the clinical scenario. LEVEL OF EVIDENCE: Level III; retrospective comparative study.

Into-Tunnel Repair Versus Onto-Surface Repair for Rotator Cuff Tears in a Rabbit Model.

BACKGROUND: Clinically, onto-surface repair is commonly used for rotator cuff tears. The retear rate after rotator cuff repair (RCR) is relatively high, with failure occurring mostly at the tendon-bone connection site. For anterior cruciate ligament (ACL) reconstruction, into-tunnel reconstruction is commonly employed. The retear rate after ACL reconstruction is relatively low, with retears seldom occurring at the tendon-bone interface. No study on into-tunnel RCR has been conducted. HYPOTHESIS: Into-tunnel RCR could promote fibrocartilage regeneration at the tendon-bone interface and has biomechanical advantage over onto-surface repair in a rabbit rotator cuff tear model. STUDY DESIGN: Controlled laboratory study. METHODS: Thirty-six New Zealand White rabbits were used in this study. The supraspinatus tendons were cut from the footprint to create a rotator cuff tear on both shoulders. On one side, the supraspinatus was cut longitudinally into 2 halves, sutured, and pulled into 2 tunnels through the greater tuberosity (into-tunnel repair). On the other side, the tendon was reattached to the surface of the footprint with transosseous sutures (onto-surface repair). Twelve animals were sacrificed, of which 6 were used for a histological examination and the other 6 for biomechanical testing, at 4, 8, and 12 weeks, respectively. RESULTS: The tendon-bone interface in the into-tunnel group showed a different healing pattern from that in the onto-surface group. In the former, most of the tendon tissue in the tunnel was replaced with newly generated fibrocartilage; the rest of the tendon fibers appeared in large bundles with direct connection to the bone. In the latter, fibrocartilage regeneration was seldom found at the tendon-bone interface; the tendon near the bone surface appeared as small fibrils. The biomechanical evaluation revealed a higher ultimate load ( P < .001) and stiffness ( P < .001) at the tendon-bone junction in the into-tunnel group than those in the onto-surface group at 12 weeks. CONCLUSION: In a rabbit rotator cuff tear model, into-tunnel RCR could result in a different tendon-bone healing pattern, with obvious fibrocartilage regeneration at the interface and higher tendon-bone healing strength than that in onto-surface repair. CLINICAL RELEVANCE: New RCR patterns may be developed to improve the tendon-bone healing pattern and obtain better tendon-bone healing strength.

Revision Hip Arthroscopy After Labral Reconstruction Using Iliotibial Band Autograft: Surgical Findings and Comparison of Outcomes With Labral Reconstructions Not Requiring Revision.

PURPOSE: To determine the causes of revision hip arthroscopy in patients who underwent labral reconstruction and to compare outcomes of these patients with patients who did not require a revision following reconstruction. METHODS: Patients who underwent revision hip arthroscopy after previous labral reconstruction from 2006 to 2014 were included. Patients with less than 2-year follow-up, preoperative joint space of ≤2 mm, or who underwent other reconstructive procedures at the time of labral reconstruction were excluded. Each patient was matched by year of surgery, age, gender, and the number of previous surgeries with 2 patients that underwent labral reconstruction but did not require a revision following the reconstruction. Preoperatively and at a minimum 2-year follow-up, outcome scores were collected including the Hip Outcome Score-Activities of Daily Living (HOS-ADL) and HOS-Sports Scale, modified Harris Hip Score, Western Ontario and McMaster Universities Index (WOMAC), the 12-Item Short Form Health Survey (SF-12) Physical Component Summary, and the patient satisfaction outcome were collected. Differences between the preoperative and the postoperative outcomes score of each patient in the 2 groups was assessed using the paired t test. The Mann-Whitney U test was used to compare the 2 groups. RESULTS: From 347 patients who underwent iliotibial band autograft labrum reconstruction from 2006 to 2014, 28 hips (8%) in 26 patients (18 females and 8 males) had revision arthroscopy after labral reconstruction. The mean age was 32 years (range: 16-64). The mean number of hip surgeries prior to the labral reconstruction was 1.9 ± 1.2. The average time from the last labral reconstruction procedure to revision labral reconstruction was 27 months (range: 5-59). Procedures performed at revision included lysis of adhesions (100%), additional femoroacetabular impingement (FAI) correction (50%), ligamentum teres debridement (50%), psoas release (29%), labral augmentation or reconstruction (14%), and others. Following revision surgery after previous labral reconstruction, 4 patients (14%) underwent total hip arthroplasty and 2 (7%) patients required a subsequent revision arthroscopy (age 67 and 23) at 15 months and 16 months. The average follow-up time was 3.6 years ± 1 year after revision following labral reconstruction and after labral reconstruction in the nonrevision group. No significant difference was detected in the outcome scores and postoperative satisfaction between the 2 groups. The HOS-ADL improved 16 points in the nonrevision group and 19 points in the revision group. CONCLUSIONS: Patients who underwent revision surgery after labral reconstruction were mostly female, with 2 or more surgeries prior to reconstruction, and 14% required THA and 7% had recurrent scarring. In those who did not fail, outcomes significantly improved and were similar with patients who did not need revision. Adhesions and residual FAI were the most common findings during revision labral reconstruction. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Excision of Labral Amorphous Calcification as a Part of Hip Arthroscopy-Clinical Outcomes in a Matched-Controlled Study.

PURPOSE: To evaluate clinical outcomes, demographics, and radiographic findings for patients whose hip arthroscopies involved amorphous calcification (AC) excision and to compare them with a control group with no AC and with the general population regarding diabetes mellitus and hypothyroidism. METHODS: Patients who underwent primary hip arthroscopy involving surgical excision of AC deposit in the anterosuperior labralcapsular recess between October 2008 and July 2014 were reviewed. Demographics, radiographic findings, intraoperative findings, and procedures were reviewed. Minimum follow-up was 2 years and included visual analog scale for pain, patient satisfaction, and the following patient-reported outcome scores: modified Harris hip score, hip outcomes score sport-specific subscale, and nonarthritic hip score. These patients were matched (1:2 ratio) to patients who underwent hip arthroscopy with no AC using the following matching criteria: age at surgery ± 5 years, body mass index ± 5, gender, type of labral treatment, and type of capsular treatment. RESULTS: We reviewed 12 cases in 11 female patients. Mean latest follow-up scores improved from 64.0 to 83.4 (P = .003) for modified Harris hip score, from 57.6 to 80.6 (P < .001) for nonarthritic hip score, from 35.4 to 62.7 (P = .021) for hip outcomes score sport-specific subscale, and from 6.4 to 2.8 (P = .016) for visual analog scale. The survivorship rate was 91.7%, with one hip converting to total hip arthroplasty. Mean patient satisfaction was 8.4 ± 2.3. Six hips of the 12 (50%) had clock face localization of the AC. They were all between 11 and 12 with a mean of 12:30. Postoperative radiographic findings showed no subsequent AC in all 12 hips. No complications or revisions were reported. There were no significant differences between the AC group and the control group. CONCLUSIONS: The treatment of AC as part of hip arthroscopy for labral tear and femoro-acetabular impingement is safe and has favorable and similar outcomes compared with a control group at minimum 2-year follow-up. Female gender may be a risk factor for the development of AC. There is no strong evidence that AC should be debrided. LEVEL OF EVIDENCE: Level III, case control study.

Acetabular All-Suture Anchor for Labral Repair: Incidence of Intraoperative Failure due to Pullout.

PURPOSE: To report on the incidence and features of intraoperative anchor pullout in a consecutive series of patients undergoing arthroscopic labral repair of the hip. METHODS: Over an 18-month period, 434 consecutive cases underwent labral repair by a single surgeon with a particular anchor system. The following data were recorded: (1) age and gender of all cases; (2) number of anchors used; (3) number of cases in which intraoperative anchor failure occurred; (4) number of anchors that failed; and (5) age and gender of those cases in which anchor failure occurred. Failures were reported for 3-month intervals. One patient underwent repair with an alternative anchor system during this time period and was excluded. RESULTS: Mean age was 34.2 (14-71) years with 180 males and 254 females. A total of 2,007 anchors were used, averaging 4.6 per case (1-8). Thirty-three anchors pulled out among 30 patients, representing a 1.6% incidence among all anchors. Mean age among pullouts was 37.8 (17-54) years with 11 males and 19 females. There was no difference compared with patient population in which no anchor pulled: mean 33.9 (14-71) years (P = .085) with 169 males and 235 females (P = .578). Pullouts were evenly distributed over the 3-month intervals (4, 4, 6, 6, 5, 8). Pullout was mostly due to failure to securely imbed the anchor in bone. Only 2 were known to pull out in the presence of being securely seated in bone. CONCLUSIONS: These data support that the security of this particular all-suture anchor at implantation is exceptionally reliable for a single experienced surgeon, and there is no demonstrable learning curve. LEVEL OF EVIDENCE: Level IV, retrospective review of a case series.

Efficacy of bone marrow-stimulating technique in rotator cuff repair.

BACKGROUND: This study used a chronic rotator cuff (RC) tear model to investigate the effect of microfracture as a bone marrow-stimulating (BMS) technique for RC healing. METHODS: A chronic retracted RC tendon tear model was created bilaterally in the subscapularis tendons of 20 New Zealand rabbits. The tendons were repaired after 8 weeks using a single-row configuration. Tendons in the right shoulder were repaired in standard fashion (control group). Microfractures were performed in the left shoulders before repair (microfracture group). The animals were euthanized 8 and 16 weeks after repair. The repaired tendons were tested biomechanically for their ultimate failure load, linear stiffness, and elongation at failure. Gross and histologic evaluations of the tendon-to-bone healing were evaluated. RESULTS: Macroscopically, subscapularis tendons were attached on the lesser tuberosity. In the microfracture group, collagen fibers were organized in relatively thicker bundles. The mean ultimate failure load of the microfracture group was significantly greater at 8 weeks (148.4 ± 31 N vs. 101.4 ± 26 N, respectively; P = .011) and 16 weeks (155 ± 30 N vs. 114.9 ± 25 N, respectively; P = .017) after repair. There were no significant differences between the groups for linear stiffness at 8 weeks (15.9 ± 2.7 N/mm vs. 15.8 ± 1.3 N/mm, respectively; P = .798) and 16 weeks (16.9 ± 4.3 N/mm vs. 17.1 ± 3.6 N/mm, respectively, P = .848) and elongation at failure at 8 weeks (4.7 ± 1.1 mm vs. 4.7 ± 1.3 mm, respectively; P = .848) and 16 weels (4.8 ± 1.5 mm vs. 4.9 ± 0.9 mm, respectively; P = .749). CONCLUSION: The microfracture on the tuberosity of the repaired chronic rotator cuff tear promoted dynamic tendon healing with significantly increased ultimate force to failure and with thicker collagen bundles and more fibrocartilage histologically at 8 weeks.

Brake Reaction Time After Hip Arthroscopy for Femoroacetabular Impingement and Labral Tear.

PURPOSE: To determine if a difference exists in brake reaction time (BRT) before and after hip arthroscopy for femoroacetabular impingement (FAI) and labral tear compared with age- and gender-matched controls. METHODS: Consecutive adult subjects undergoing primary hip arthroscopy were eligible for this prospective investigation. Individuals with symptomatic FAI and labral tear that underwent hip arthroscopy with minimum 8 weeks follow-up were included. BRT was measured using the RT-2S reaction time tester a maximum of 6 weeks preoperatively and every 2 weeks postoperatively for 8 weeks. Sit-to-stand test (STST) was measured at each BRT testing session. An age- and gender-matched control group without hip or lower extremity symptoms were selected and completed both BRT and STST. Continuous pre- and postoperative BRT values were compared with Mann-Whitney and analyses of variance. Association of BRT and STST tests was performed with Spearman correlation. An a priori sample size calculation determined that minimally 18 subjects per group (surgery group vs control group) were necessary to detect, with 80% power (difference of 0.2 seconds in BRT). RESULTS: Nineteen subjects (age 37.1 ± 12.7 years, 10 women, 11 right hip) were analyzed. All subjects underwent arthroscopic labral repair and FAI correction. There was no difference between preoperative (604 ± 148 milliseconds [ms]) and postoperative (608 ms 2 weeks; 566 ms 4 weeks; 559 ms 6 weeks; 595 ms 8 weeks) BRT. There was no difference between controls and subjects at any time point. There was a strong negative correlation between BRT and STST preoperatively and at 4 and 6 weeks postoperatively and a moderate negative correlation at 2 weeks postoperatively. CONCLUSIONS: After hip arthroscopy for FAI and labral tear, BRT is not different from preoperative values or that of controls. In addition, BRT had a significant correlation with STST in the first 6 weeks after surgery. LEVEL OF EVIDENCE: Level II, diagnostic, prospective.

Outcome after hip arthroscopy for femoroacetabular impingement in 289 patients with minimum 2-year follow-up.

Femoroacetabular impingement (FAI) is a common cause of hip pain and dysfunction. The purpose of this study was to report outcome 2 years after the arthroscopic treatment of FAI using validated outcome measurements. Two hundred and eighty-nine patients (males = 190, females = 99) with a mean age of 37 years underwent arthroscopic surgery for FAI. Patients were included consecutively in a hip arthroscopy registry. The cohort was evaluated using online web-based validated health-related patient-reported outcomes measurements, including the iHOT-12, HAGOS, EQ-5D, HSAS for physical activity level, VAS for overall hip function and overall satisfaction. The mean follow-up time was 25.4 months. Pre-operative scores compared with those obtained at follow-up revealed statistically and clinically significant improvements (P < 0.05) for all measured outcomes; iHOT-12 (43 vs 66), VAS for global hip function (50 vs 71), HSAS (2.9 vs 3.6), EQ-5D index (0.58 vs 0.75), EQ-VAS (67 vs 75) and HAGOS different subscales (56 vs 76, 51 vs 69, 60 vs 78, 40 vs 65, 29 vs 57, 33 vs 58). At the 2-year follow-up, 236 patients (82%) reported they were satisfied with the outcome of surgery. We conclude that arthroscopic treatment for FAI resulted in statistically and clinically significant improvements in outcome parameters.

Evaluation of the sealing function of the acetabular labrum: an in vitro biomechanical study.

PURPOSE: To quantitatively evaluate the biomechanical sealing function of an intact labrum and the effect of labral-chondral separation, cerclage suture labral repair, vertical mattress suture repair and partial labrectomy on distraction load and hip joint centre (HJC) displacement. METHODS: Eight fresh-frozen cadaveric hips were tested using a navigation system for intra-operative kinematic analysis. A six-axis load cell was used to measure the manually applied force when performing the tests: hip pivoting movement and distraction. The HJC displacement that occurred during the distraction test has been evaluated in correspondence of seven different values of applied force. During the pivoting motion, the maximum value of HJC displacement was evaluated. Five different conditions were tested: labrum intact, labral-chondral separation, vertical mattress suture repair, cerclage suture repair, and partial labrectomy. RESULTS: With regard to HJC displacement using at fixed value of force, the paired sample t test underscored the statistically significant differences (p < 0.05) for each of the five tested conditions among themselves. Only the comparison of intact versus labral-chondral separation was not significantly different. During pivoting motion, a statistically significantly greater displacement was identified after labrectomy when compared with the cerclage suture repair (p = 0.03) and vertical mattress repair (p < 0.01) in medial-lateral direction. Along proximal-distal direction, a significant lower displacement after labrectomy was identified when compared to the cerclage suture repair (p = 0.03). Performing the pivoting motion at the extreme ranges of motion demonstrated a higher value of displacement after labrectomy when compared with all the previously tested conditions. CONCLUSIONS: These results suggest that labral repair is important in the function of the hip and that the vertical mattress suture technique may be better than the cerclage suture repair.