Fixation strength in arthroscopic labral repair of the hip: A head-to-head comparison of the biomechanical performance of a biocompatible vs. all-suture anchor in the setting of acetabuloplasty.

Much is known about the biomechanical performance of various types of suture anchors commonly used for labral fixation in the shoulder; however, similar studies in the hip are less common. We sought to compare all-suture and polyether ether ketone small-diameter anchors in the setting of labral repair during hip arthroscopy, with and without acetabuloplasty. We hypothesized that the biomechanical properties of the all-suture group when compared to polyether ether ketone anchors would be similar amongst native acetabula and significantly less following acetabuloplasty and that pullout forces would be reduced in the anterior and inferior regions of the acetabulum compared to the superior region. Bone density was measured in nine matched pairs of fresh-frozen cadaveric acetabula in the superior, anterosuperior, and anterior regions. Acetabuloplasty was performed in all three regions, while the contralateral acetabulum was left in situ as a control. Suture anchors were placed such that one each of two different types was placed within each region. Specimens were tested in cyclic fatigue and loaded to failure. The all-suture group had significantly higher cyclic displacement compared to the polyether ether ketone, but there was no significant difference in ultimate load, regardless of acetabuloplasty. Amongst all non-resected specimens, the lowest bone density was observed consistently in the inferior region. Our results indicate that, with or without acetabuloplasty, a small-diameter polyether ether ketone anchor appears to be more stable than an all-suture anchor, which needs to be set first.

Editorial Commentary: #Capsule-ophilesRejoice! The Evidence in Support of Diligent Capsular Management During Hip Arthroscopy Can No Longer Be Ignored.

From its infancy until now, the enthusiasm and growth of the field of hip arthroscopy have been exciting to watch. Perhaps, it could be argued that there has not been a more hotly debated topic in recent years than what to do with the hip capsule. Once merely an afterthought in the context of hip arthroscopy, the oft overlooked and underappreciated intricacies of hip capsular anatomy and its role in hip stability have now taken center stage. As surgical indications continue to expand, our surgical techniques have rapidly evolved. Despite the rapid growth and advent of industry, the leaders in this field have remained steadfast in their relentless quest to improve their scientific knowledge and understanding of the native hip joint. If we have learned nothing else from watching the capsular debate evolve, it is that without an advanced understanding of the critical and complex marriage of anatomy and function that exists in a healthy hip joint, we cannot begin to master the surgical treatment of its pathologic states.

Ulnar Collateral Ligament Repair With Collagen-Dipped FiberTape Augmentation in Overhead-Throwing Athletes.

BACKGROUND: There has been a renewed interest in ulnar collateral ligament (UCL) repair in overhead athletes because of a greater understanding of UCL injuries, an improvement in fixation technology, and the extensive rehabilitation time to return to play. PURPOSE/HYPOTHESIS: To evaluate the clinical outcomes of a novel technique of UCL repair with internal brace augmentation in overhead throwers. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Patients undergoing a novel technique of UCL repair with internal brace augmentation were prospectively followed for a minimum of 1 year. Potential candidates for repair were selected after the failure of nonoperative treatment when imaging suggested a complete or partial avulsion of the UCL from either the sublime tubercle or medial epicondyle, without evidence of poor tissue quality of the ligament. The final decision on UCL repair or traditional reconstruction was determined intraoperatively. Demographic and operative data were collected at the time of surgery. Return to play, and Kerlan-Jobe Orthopaedic Clinic (KJOC) scores were collected at 1 year and then again at 2 years postoperatively. RESULTS: Of the 111 overhead athletes eligible for the study, 92% (102/111) of those who desired to return to the same or higher level of competition were able to do so at a mean time of 6.7 months. These patients had a mean KJOC score of 88.2 at final follow-up. CONCLUSION: UCL repair with internal brace augmentation is a viable option for amateur overhead throwers with selected UCL injuries who wish to return to sport in a shorter time frame than allowed by traditional UCL reconstruction.

Effect of Intraoperative Platelet-Rich Plasma Treatment on Postoperative Donor Site Knee Pain in Patellar Tendon Autograft Anterior Cruciate Ligament Reconstruction: A Double-Blind Randomized Controlled Trial.

BACKGROUND: Donor site morbidity in the form of anterior knee pain is a frequent complication after bone-patellar tendon-bone (BPTB) autograft anterior cruciate ligament (ACL) reconstruction. Hypothesis/Purpose: The purpose was to examine the effect of the intraoperative administration of platelet-rich plasma (PRP) on postoperative kneeling pain. It was hypothesized that PRP treatment would reduce knee pain. STUDY DESIGN: Randomized controlled trial; Level of evidence, 2. METHODS: Fifty patients (mean ± SD age, 30 ± 12 years) undergoing BPTB ACL autograft reconstruction were randomized to the PRP (n = 27) or sham (n = 23) treatment. In either case, 10 mL of venous blood was drawn before the induction of anesthesia and either discarded (sham) or processed (PRP) for preparation of a PRP gel to be later mixed with donor site bone chips and inserted into the patellar defect. At 12 weeks, 6 months, 1 year, and 2 years after surgery, patients completed International Knee Documentation Committee (IKDC) forms and visual analog scale pain scores for activities of daily living and kneeling. Healing indices at the donor site were assessed by routine noncontrast magnetic resonance imaging (MRI) at 6 months. Mixed-model analysis of variance was used to assess the effect of PRP on patient symptoms and MRI indices of donor site healing, as measured by the width of the donor site defect. RESULTS: Kneeling pain, pain with activities of daily living, and IKDC scores were not different between treatment groups at any of the time intervals ( P = .08-.83). Kneeling pain improved from 12 weeks to 6 months and from 1 to 2 years ( P < .05). IKDC scores improved substantially from 12 weeks to 6 months ( P < .001) and continued to improve to 2 years (PRP, 86 ± 19; sham, 89 ± 10). MRI indices of donor site healing were not different between treatment groups ( P = .53-.90). CONCLUSION: Whether randomized to receive PRP in their patellar defect or not, patients continued to have similar levels of kneeling pain and patellar defect sizes after autograft BPTB ACL reconstruction. Registration: NCT01765712 ( ClinicalTrials.gov identifier).

Biomechanical Comparison of Ulnar Collateral Ligament Repair With Internal Bracing Versus Modified Jobe Reconstruction.

BACKGROUND: The number of throwing athletes with ulnar collateral ligament (UCL) injuries has increased recently, with a seemingly exponential increase of such injuries in adolescents. In cases of acute proximal or distal UCL insertion injuries or in partial-thickness injuries that do not respond to nonoperative management, UCL repair and augmentation rather than reconstruction may be a viable option. PURPOSE/HYPOTHESIS: The purpose of this study was to biomechanically compare a new technique of augmented UCL repair versus a typical modified Jobe UCL reconstruction technique. The hypotheses were that (1) the repaired specimens would have less gap formation and a higher maximal torque to failure compared with the reconstruction group, and (2) while both groups would show an increase in gap formation after the simulated tear, the repair group would return closer to the native values compared with the reconstruction group. STUDY DESIGN: Controlled laboratory study. METHODS: Nine matched pairs of cadaveric arms were dissected to expose the UCL. Each elbow was mounted on a test frame at 90° of flexion. A cyclic valgus rotational torque was applied to the humerus with the UCL in its intact state and repeated in its surgically torn state. Finally, each specimen received either an augmented repair or reconstruction and was again put through the cyclic protocol, followed by a torque to failure. RESULTS: Gap formation (0.51 ± 0.22 mm) in the torn state for the repair group was significantly higher (P = .04) than in the intact state (0.33 ± 0.12 mm). After the procedures, the repair group (0.35 ± 0.16 mm) showed greater resistance to gapping (P = .03) compared with the reconstruction group (0.53 ± 0.23 mm). No statistical differences were found for the maximum torque at failure, torsional stiffness, or gap formation during the failure test. CONCLUSION: The current study shows that this novel technique of augmented UCL repair replicates the time-zero failure strength of traditional graft reconstruction and appears to be more resistant to gapping at low cyclic loads. CLINICAL RELEVANCE: This study demonstrates that this novel technique has important biomechanical properties, including time-zero strength and ultimate failure load, compared with the gold standard of UCL reconstruction. In some throwing athletes, this technique may supplant standard UCL reconstruction as the procedure of choice.

Anatomy of the hip capsule and pericapsular structures: A cadaveric study.

The anatomical literature contains relatively little qualitative or quantitative information regarding the anatomy of the hip joint capsule and its relationship to the surrounding pericapsular structures. We aimed to provide a detailed description of the anatomy of these relationships in a cadaveric study. Dissections of 11 nonpaired, fresh-frozen cadaveric hips were performed, documenting capsular dimensions and attachments to pericapsular structures including the rectus femoris, gluteus minimus, iliocapsularis, and piriformis and short external rotator muscles. Tendon footprints of these pericapsular muscles were measured, as well as their distance from reproducible bony landmarks. The thickest portion of the hip capsule is posterosuperiorly and superiorly near its acetabular origin, while the thinnest portion is posteriorly and posteroinferiorly near its femoral insertion. The piriformis has no capsular contribution; however, the reflected head of the rectus femoris, gluteus minimus, iliocapsularis, and external rotator tendons all demonstrate consistent capsular adhesions. There are complex associations among these structures, yet the surrounding layers of the capsule are confluent in predictable relationships. Knowledge of the intricate relationship between the hip capsule and pericapsular structures presented here will be useful for surgeons as they perform the precise and specific capsular releases required by various operative procedures. This study also provides information that can lead to further biomechanical, radiographic, and clinical studies on these structures.

New findings in hip capsular anatomy: dimensions of capsular thickness and pericapsular contributions.

PURPOSE: The purpose of this investigation was to provide a detailed description of the anatomy of the hip capsule and pericapsular structures. METHODS: Dissections were performed on 11 nonpaired, fresh-frozen cadaveric hips by 2 independent observers: 1 fellowship-trained orthopaedic total joint surgeon and 1 chief orthopaedic surgery resident. Documentation of capsular thickness, origins, insertions, and attachments to pericapsular structures including the abductors, rectus femoris, piriformis, short external rotators, and iliocapsularis muscles was performed. Tendinous insertions of the surrounding pericapsular muscles were measured according to size and distance from reproducible osseous landmarks. RESULTS: The capsule is thickest near the acetabular origin at the posterosuperior and superior hemi-quadrants and is thinnest near the femoral insertion in the posterior and posteroinferior hemi-quadrants. The iliocapsularis, indirect head of the rectus, conjoint, obturator externus, and gluteus minimus tendons all show consistent capsular contributions, whereas the piriformis does not have a capsular attachment. Osseous landmarks for tendinous attachments are defined and illustrated. The inter-relation of these structures is complex, yet their relations to the anterior hip capsule and contributions to its thickness are predictable. CONCLUSIONS: The dynamic pericapsular structures pertinent to the hip arthroscopist include the iliocapsularis, gluteus minimus, and reflected head of the rectus femoris. At the acetabulum, the thickest region of the capsule is posterosuperior and superolateral. At the femoral insertion, the thickest region is anterior. CLINICAL RELEVANCE: Knowledge of the intricate relation between the hip capsule and pericapsular structures presented here will be useful for surgeons as they perform the precise and specific capsular releases required during hip arthroscopy. Our anatomic findings contribute important qualitative data that build on the recent literature regarding the importance of capsular management during hip arthroscopy to postoperative hip stability.