Comparable Minimum 2-Year Patient-Reported Outcome Scores Between Circumferential and Segmental Labral Reconstruction for the Management of Irreparable Labral Tear and Femoroacetabular Impingement Syndrome in the Primary Setting: A Propensity-Matched Study

Labral Augmentation With Either Iliotibial Band Allograft or Dermis Allograft Perform Similarly Regarding Peak Force, Displacement, and Work to Labral Repair in Suction Seal Restoration: A Biomechanical Study

PURPOSE

To investigate whether allograft substitutes may be used to restore suctional seal properties with labral augmentation, the purpose of the current study was to evaluate the biomechanical properties of the labral suction seal under several scenarios, including: (1) intact labrum, (2) rim preparation, (3) labral repair, (4) labral augmentation with iliotibial band (ITB), and (5) labral augmentation with a dermis allograft.

METHODS

Eleven hemi-pelvises were dissected to the level of the labrum and placed in a material testing system for biomechanical axial distraction. Each specimen was compressed to 250 newtons (N) and distracted at 10 mm/s while load, crosshead displacement, and time were continuously recorded. For each of the 5 labral states, 3 testing repetitions were performed. Peak force (N, newtons), displacement at peak force (mm, millimeter), and work (N-mm, newton, millimeter) were calculated and normalized to the intact state of each specimen.

RESULTS

Eleven specimens were tested and 8 specimens (age: 58.6 ± 5.4 years, body mass index: 28.6 ± 6.8 kg/m2; 4 female patients; 5 right hips) were included in final analyses. Expressed as a percentage relative to the intact state, the average normalized peak force, displacement at peak force, and work for each labral state were as follows: intact (100.0% ± 0% for all), rim preparation (89.0% ± 9.2%, 93.3% ± 20.6%, 85.1% ± 9.0%), repair (61.3% ± 17.9%, 88.4% ± 36.9%, 58.1% ± 16.7%), ITB allograft (62.7% ± 24.9%, 83.9% ± 21.6%, 59.4% ± 22.4%), and dermis allograft (57.8% ± 27.2%, 88.2% ± 29.5%, 50.0% ± 20.1%). Regarding peak force, intact state was significantly greater compared with the labral repair, augmentation with ITB, and augmentation with the dermis allograft states (P < .001). No significant differences were demonstrated between displacement at peak force (P = .561). Regarding work, both intact state and rim preparation states were significantly greater than the repair, ITB augmentation, and dermis allograft augmentation states (P < .001). In all outcome measures, the dermis allograft augmentation performed with no statistical difference to the ITB augmentation state.

CONCLUSIONS

Labral repair and labral augmentation with either ITB allograft or the dermis allograft resulted in significantly lower peak force and work to equilibrium compared with the intact and rim prep states. There was no statistical difference between repair and augmentation states as well as no statistical difference between ITB allograft and dermal allograft at time zero.

CLINICAL RELEVANCE

This study compares biomechanical properties of the suction seal of the hip comparing labral states including intact, rim preparation, repair, and augmentation, which can be used for surgical decision-making.

Acetabular Labral Reconstruction: Review of Techniques and Outcomes

PURPOSE OF REVIEW

To analyze advances in labral reconstruction, and to discuss the literature relating to efficacy, outcomes, and technical considerations of labral reconstruction.

RECENT FINDINGS

The available evidence suggests that labral reconstruction is a safe and effective procedure that can improve pain and function in patients with severe and/or complex labral tears. The superiority of labral reconstruction over labral repair is uncertain, and it remains unclear what graft type and technique should be used in labral reconstructions. Labral reconstruction assists in restoring the function of the labrum of the hip. It consistently restores stability of the hip joint and demonstrates good clinical outcomes at follow-up. The optimal graft type, technique, and extent are still debated, and more research is needed. Ultimately, despite this uncertainty, labral reconstruction is proving to be a valuable tool for hip preservation specialists.

Single Portal Segmental Labral Reconstruction of the Hip

Many techniques have been described for reconstruction of the acetabular labrum, but the procedure is known to be technically rigorous leading to lengthy procedure times and traction times. Increasing efficiency of the procedure with respect to graft preparation and delivery remain areas for potential improvement. We describe a simplified procedure for arthroscopic segmental labral reconstruction using peroneus longus allograft and a single working portal to shuttle the graft into the joint via suture anchors placed at the terminal extents of the graft defect. This method allows for efficient preparation, placement and fixation of the graft that can be completed in under 15 minutes.

Treatment of Severe Pincer-Type Femoroacetabular Impingement With Arthroscopic Significant Acetabular Rim Correction and Circumferential Labral Reconstruction Improves Patient-Reported Outcome Measures

PURPOSE

To validate an arthroscopic approach for performing significant acetabular rim correction and circumferential labral reconstruction required to treat severe pincer-type femoroacetabular impingement.

METHODS

Using a minimum of 2-year follow-up, data from 48 hips, including 47 patients (11 male, 36 female; mean age of 42 years) having undergone significant arthroscopic acetabuloplasty for severe pincer impingement (center edge angle >45°) with concomitant circumferential allograft labral reconstruction were analyzed to determine improvements in patient-reported outcomes and degree of radiographic correction.

RESULTS

Findings demonstrated a 98% success rate, including substantial improvements on all radiographic measurements and patient-reported outcomes. Minimal clinically important differences were met with extremely strong measures of effect. The mean center edge angle improved from 49° to 36° (MΔ = 13.96, P ≤ .001, standard deviation [SD] = 55.97, confidence interval [CI] 12.17- 15.62, d = 2.33) and the mean Tönnis angle improved from -6° to 0° (MΔ = 6.2, P ≤ .001, SD = 2.76 CI -7.1 to -5.39, d = 2.29). Modified Hip Harris Scores improved by a mean of 34.45 points (P ≤ .001, SD = 20.64, 95% CI 28.45-40.44, d = 1.66). Lower extremity functional scale scores improved by a mean of 27.35 points (P ≤ .001, SD = 18.37, 95% CI 22.02-32.69, d =1.48). No complications were reported. One case converted to a total hip arthroplasty (2%).

CONCLUSIONS

Findings validated that the significant acetabular rim correction required to treat severe pincer morphology is safe and feasible via an arthroscopic approach. This, in addition to concomitant circumferential allograft labral reconstruction, resulted in improvement in patient-reported outcomes and radiographic measurements.

LEVEL OF EVIDENCE

Level IV, therapeutic case-series.

An Increased Allograft Width for Circumferential Labral Reconstruction Better Restores Distractive Stability of the Hip: A Cadaveric Biomechanical Analysis

BACKGROUND

Questions remain about whether circumferential labral reconstruction (CLR) using an iliotibial band (ITB) allograft can effectively restore the labral suction seal of the hip.

HYPOTHESES

(1) CLR with an ITB allograft >6.5 mm would restore distractive stability force to that of the intact labrum. (2) CLR with an ITB allograft >6.5 mm would achieve significantly superior distractive stability force compared with CLR with an ITB allograft <6.5 mm.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 6 fresh-frozen pelves with attached femurs (n = 12 matched hemipelves) from male donors were procured and dissected free of all soft tissue, including the hip capsule but preserving the native labrum, transverse acetabular ligament, and ligamentum teres. Potted hemipelves were placed in a saline bath and securely fixed to the frame of a hydraulic testing system. A 500-N compressive load was applied, followed by femoral distraction at a rate of 5.0 mm/s until the suction seal ruptured. Force and femoral displacement were continually recorded. Force versus displacement curves were plotted, the maximum force was recorded, and the amount of femoral distraction to rupture the suction seal was determined. After intact testing, the labrum was excised, and specimens were retested using the same protocol. CLR was subsequently performed twice in a randomized fashion using (1) an ITB allograft with a width >6.5 mm (7.5-9.0 mm) and (2) an ITB allograft with a width <6.5 mm (4.5-6.0 mm). Specimens were retested after each CLR procedure. Force (in Newtons) and femoral distraction (in millimeters) required to rupture the suction seal were measured and compared between the 4 testing states (intact, deficient, CLR <6.5 mm, and CLR >6.5 mm) using repeated-measures analysis of variance.

RESULTS

On average, intact specimens required 148.4 ± 33.1 N of force to rupture the hip suction seal, which significantly decreased to 44.3 N in the deficient state (P < .001). CLR with ITB allografts <6.5 mm did not improve the maximum force (63 ± 62 N) from the deficient state (P = .42) and remained significantly lower than the intact state (P < .01). CLR with ITB allografts >6.5 mm recorded significantly greater force to rupture the suction seal (135.8 ± 44.6 N) compared with both the deficient and CLR <6.5 mm states (P < .01), with a mean force comparable with the intact labrum (P = .59). The amount of femoral distraction to rupture the suction seal demonstrated similar findings.

CONCLUSION

In a cadaveric model, CLR using ITB allografts >6.5 mm restored the distractive force and distance to the suction seal rupture to values comparable with hips with an intact labrum. CLR using ITB allografts >6.5 mm outperformed CLR with ITB allografts <6.5 mm, demonstrated by a significantly higher force to rupture the suction seal and increased distraction before the rupture.

CLINICAL RELEVANCE

The results of this cadaveric investigation suggest that using wider labral allografts during CLR will provide the distractive force required to rupture the suction seal and immediate postoperative stability of the hip, although further studies are required to determine if these results translate to improved clinical outcomes.

Allograft Labral Reconstruction of the Hip: Expanding Evidence Supporting Greater Utilization in Hip Arthroscopy

Purpose of Review

The current review investigates outcomes and failure rates associated with arthroscopic circumferential allograft labral reconstruction of the hip, both as a revision and primary procedure in treating femoroacetabular hip impingement and labral-related pathology.

Recent Findings

Numerous studies within the last decade have demonstrated excellent patient-reported outcomes, high rates of return-to-play in athletes, and low failure rates in patients having undergone arthroscopic circumferential allograft labral reconstruction of the hip. Removal of chronically diseased and injured labral tissue can eliminate a significant pain-generator from the hip joint. Additionally, circumferential reconstruction of the labrum restores the hoop fiber strength and fluid seal akin to what would be seen with native, healthy labral tissue. Recent research has shown that arthroscopic circumferential allograft labral reconstruction may be used not only in the revision setting, but as a primary procedure. Circumferential labral reconstruction should be considered when a surgeon feels that the labrum is irreparable or has failed previous repair.

Summary

Arthroscopic circumferential allograft labral reconstruction of the hip can be utilized as treatment option not only in revision settings, but also in primary treatment for femoroacetabular impingement and labral pathology

Editorial Commentary: Segmental Hip Labral Reconstruction May Be Superior to Circumferential Reconstruction: Bigger Isn't Better

Hip arthroscopic segmental and circumferential labral reconstruction show similar outcomes in short-term follow-up. Will bigger (circumferential reconstruction) eventually be largely a historical method? Bigger does not appear to be better, although some argue that segmental techniques inadequately restore the labrum's function, incompletely treat the defect, and result in mismatch at the labral-graft junction, which is also a "weak spot" for future tears. Yet, others show that circumferential reconstruction is without clear benefit and adds additional anchors, complexity and operating room time and costs. The next phase of research on hip labral reconstruction requires evaluation of the numerous variables within the category of "reconstruction." Today, a great number of different reconstruction techniques exist. Measuring a segmental defect can be challenging but is facilitated with methods such as the kite technique, use of a shoulder superior capsular reconstruction guide, or a pull-through method to simply avoid measuring. Graft options include ligamentum teres and iliotibial band, anterior and posterior tibialis, hamstring, fascia lata, autograft and allograft. Graft preparation, passage, and fixation techniques also vary widely. Finally, determining how much overlap with native labrum, ideal graft tension, or integrating the transverse acetabular ligament is more art than science. It's time we begin to critically evaluate the differences in reconstructive techniques.

Arthroscopic Treatment of Femoroacetabular Impingement Using Labral Reconstruction with Capsular Autograft

The acetabular labrum is essential for stability during physiologic motion of the hip. Labral repairs frequently are attempted in cases of primary tears, although labral reconstruction is an important alternative in the revision setting or in the primary setting when the tissue is unsalvageable. Labral reconstruction has been shown to restore the hip's suction-seal and fluid pressurization to that of the premorbid state, and cohort studies have demonstrated significantly improved patient-reported outcomes at midterm follow-up. Notably, the cost is of consideration during any reconstruction, and techniques have been described using both allograft and autograft sources. Autograft sources include the iliotibial band, ligamentum teres, gracilis tendon, and hip capsule. A previously described technique using the capsule was noted to hinder routine capsular closure. We present an alternative method for labral reconstruction using hip capsular tissue that is easily performed and allows for routine capsular closure.