Superior Capsule Reconstruction Using Acellular Dermal Allograft Secured at 45° of Glenohumeral Abduction Improves the Superior Stability of the Glenohumeral Joint in Irreparable Massive Posterosuperior Rotator Cuff Tears

Editorial Commentary: Both Rotator Cuff Repair and Superior Capsular Reconstruction in Patients With Diabetes Show Good Outcomes When Glucose Is Well Managed

Diabetes has been reported to be a significant risk factor for rotator cuff repair, both for increased complication rates and poor cuff integrity at final follow-up. Similar results might be expected for superior capsular reconstruction; however, strict glucose management, as with rotator cuff repair, is shown to allow these rotator cuff procedures to proceed with success rates similar to patients without diabetes.

Early failure of superior capsule reconstruction with human dermal allograft (Epiflex) in patients with massive rotator cuff tears: a clinical and radiological analysis

BACKGROUND

Massive rotator cuff tears (MRCT) are one of the major challenges in reconstructive shoulder surgery and the therapeutic concepts are still controversial. Using conventional reconstruction techniques rotator cuff re-tear rates still occur up to 52%-94% according to the recent literature. Therefore, superior capsule reconstruction (SCR) using acellular human dermal allografts (AHDG) are currently a frequently applied alternative treatment option for MRCT. Although the functional outcome improves, there is some discrepancy in survival time of the graft. The purpose of this study was to evaluate the structural graft integrity by magnetic resonance imaging (MRI) scans and the functional status of the shoulder early after surgery.

MATERIALS AND METHODS

Twenty-nine patients with conventionally irreparable MRCT were treated with an arthroscopic SCR utilized an AHDG (Epiflex, DIZG). Pre- and postoperative MRIs were used to evaluate the rotator cuff and graft configuration. The mean MRI follow-up was 9.8 ± 3.9 (6-21) weeks. The functional status was recorded regarding the Constant Score (CS) and active range of motion. General complications were noted. The clinical follow-up (FU) was 9.4 ± 2.9 (6-17) weeks and 1 year postoperatively at 42.5 ± 5.7 (36-58) weeks.

RESULTS

The presence of a total graft failure rate of 59% type 3 according to Mirzayan after SCR with AHDG did not negatively influence the functional outcome during the observation period. There was the main effect of time on all directions of range of motion and all categories of the CS-Score (pain: P < .001, activity: P = .01 and motion: P = .04) except for CS-force value (P = .28) at the first FU and the improvement remained constant until the last FU. There were no significant differences in clinical outcome between the group with graft failure and the group with intact graft at the first and last FU.

CONCLUSIONS

The SCR with AHDG in MRCT shows high rate of structural graft failures in early postoperative MRI. However, this does not correlate with the functional outcome in early and mid-term FU. Further studies focusing to elucidate the underlying complex process of in vivo AHDG regeneration and recent developments of biological graft healing and surgery techniques may improve the structural integrity of the SCR construct.

Superior capsule reconstruction using 8mm-thick fresh-frozen fascia lata graft for irreparable supraspinatus and infraspinatus tendon tears: A cadaveric biomechanical study

BACKGROUND

Superior capsule reconstruction (SCR) was developed to restore superior glenohumeral stability and function to shoulder joints with irreparable rotator cuff tears. Previous biomechanical studies have investigated the effects of SCR using dermal graft or freeze-dried fascia lata allograft. The objective of the current study was to investigate the effect of SCR using fresh-frozen fascia lata graft, which closely resembles the fresh fascia lata autograft used clinically, on shoulder biomechanics in irreparable rotator cuff tendon tear.

METHODS

Eight fresh-frozen cadaveric shoulders were tested by using a custom testing device. Subacromial peak contact pressure (pressure sensor), superior glenohumeral translation (three-dimensional digitizing system), and glenohumeral range of motion (goniometer) were compared under three conditions: (1) intact shoulder; (2) simulated irreparable rotator cuff (supraspinatus and infraspinatus) tear; and (3) SCR using fresh-frozen fascia lata graft. SCR was performed according to the technique for SCR using fascia lata autograft. The average graft thickness was 8.6 mm at the medial edge and 8.9 mm at the lateral edge.

RESULTS

Compared with the intact condition, creation of the irreparable rotator cuff tear increased superior translation and subacromial peak contact pressure at 0° (P < 0.01) and 30° (P < 0.001) of glenohumeral abduction. SCR using fresh-frozen fascia lata graft decreased superior translation and subacromial peak contact pressure to the intact level (P < 0.01 for both). SCR using fresh-frozen fascia lata graft did not decrease internal (P = 0.15 to 0.99), external (P = 0.90 to 0.99), or total (P = 0.35 to 0.98) rotation at 0°, 30°, or 60° of glenohumeral abduction, compared with the irreparable supraspinatus and infraspinatus tendon tear condition.

CONCLUSION

For irreparable supraspinatus and infraspinatus tendon tear, SCR using 8 mm-thick fresh-frozen fascia lata graft restored superior glenohumeral stability to the intact level without any restriction of glenohumeral range of motion after surgery.

Improved restoration of biomechanical factors using a narrow-box shaped reconstruction compared to a wide one in superior capsular reconstruction for irreparable supraspinatus tendon tears: a biomechanical study using a static shoulder simulator

HYPOTHESIS AND/OR BACKGROUND

Extensive, irreparable rotator cuff tears remain a surgical challenge and multiple treatment options are proposed and currently in use. To biomechanically compare superior glenohumeral translation, subacromial contact pressures, and area in a box-shaped reconstruction using the long head of the biceps tendon (LHBT) in an irreparable supraspinatus tendon tear model.

METHODS

Seven cadaveric shoulders (mean age 61 years; range 32-84 years; standard deviation 22.3) were tested with a custom testing rig used to evaluate superior translation; subacromial contact pressures; and areas at 0°, 30°, and 60° of glenohumeral abduction. Conditions tested included the native state; a complete tear of the supraspinatus tendon; a wide box-shaped, double-bundle LHBT superior capsular reconstruction (BS-SCR); and a narrow BS-SCR.

RESULTS

Compared with the wide BS-SCR, the narrow BS-SCR had statistically significantly lower median contact pressure at 30° and 60°. The subacromial contact area showed a statistically significant difference at 0° (P = .001) and 30° (P = .004) for the narrow BS-SCR compared with the wide BS-SCR. At an abduction angle of 0°, the narrow BS-SCR could restore superior translation significantly better compared with the wide construct. For all angles, the wide and narrow BS-SCR increased the median subacromial distance statistically significantly. The contact areas in 30° and 60° of abduction were higher for all scenarios, both peaking in the intact state in 30° with approximately 600 mm2.

CONCLUSIONS

In comparison to a wide BS-SCR, a narrow BS-SCR using the LHBT has biomechanical advantages in regard to subacromial contact pressures, the subacromial contact areas, as well as the acromiohumeral distance. The width of the reconstruction, therefore, has a direct influence on the success of the technique.

Supraspinatus Tendon Reconstruction Using Fascia Lata Autograft for Irreparable Posterosuperior Massive Rotator Cuff Tears

Superior capsule reconstruction has shown good long-term clinical efficacy in treating irreparable posterosuperior massive rotator cuff tears. However, conventional superior capsule reconstruction did not treat the medial supraspinatus tendons. Therefore, dynamic function of the posterosuperior rotator cuff does not restore effectively, especially the function of active abduction and external rotation. We describe a supraspinatus tendon reconstruction technique that presents a stepwise approach to accomplish the dual goals of stable anatomic reconstruction and restoring the dynamic function of the supraspinatus tendon.

Editorial Commentary: Superior Capsule Reconstruction: Acellular Allograft at 45° of Glenohumeral Abduction Improves Glenohumeral Stability, but Fascia Lata Autograft Remains Superior

Originally, fascia lata autograft was used for superior capsule reconstruction (SCR) to restore glenohumeral stability in irreparable rotator cuff tears. Consistently excellent clinical outcomes with low graft tear rates have been reported, without repair of tears in the supraspinatus and infraspinatus tendons. On the basis of our experience and studies published in the 15 years since the first SCR using fascia lata autograft in 2007, we can say that this technique is the gold standard. SCR using fascia lata autograft can cover all irreparable rotator cuff tears (Hamada grade 1-3; although the indication for SCR using other grafts, including dermal allograft, biceps, and hamstrings, is only Hamada grade 1 or 2); creates excellent clinical outcomes with low graft tear rates in short-term, long-term, and multicenter studies; regenerates the fibrocartilaginous insertions at both the greater tuberosity and superior glenoid according to histological study; and enables complete restoration of shoulder stability and subacromial contact pressure in cadaveric biomechanical studies. In some countries, dermal allograft is preferred for SCR. However, high rates of graft tear and complications have been reported after SCR using dermal allografts, even in limited indications of irreparable rotator cuff tears (Hamada grade 1 or 2). This high failure rate results from the lack of stiffness and thickness of the dermal allograft. Dermal allografts in SCR can be elongated by 15% after only a couple of physiological shoulder movements, whereas fascia lata graft cannot. This 15% graft elongation, which creates less glenohumeral stability and high graft tear after SCR, is a fatal problem of dermal allograft for SCR in irreparable rotator cuff tears. Current research suggests that SCR using dermal allografts is not strongly recommended for the treatment of irreparable rotator cuff tears. Dermal allograft probably should be used only for augmentation of rotator cuff complete repair.

Superior Capsular Reconstruction Partially Restores Native Glenohumeral Joint Loads In A Dynamic Biomechanical Shoulder Model

PURPOSE

To evaluate the effect of an irreparable posterosuperior rotator cuff tear (PSRCT) on glenohumeral joint loads and to quantify improvement following superior capsular reconstruction (SCR) using an acellular dermal allograft.

METHODS

Ten fresh-frozen cadaveric shoulders were tested using a validated dynamic shoulder simulator. A pressure mapping sensor was placed between the humeral head and glenoid surface. Each specimen underwent the following conditions: (1) native, (2) irreparable PSRCT, (3) SCR using a 3mm-thick acellular dermal allograft. Glenohumeral abduction angle (gAA) and superior humeral head migration (SM) were measured using 3D motion tracking software. Cumulative deltoid force (cDF) and glenohumeral contact mechanics, including contact area (gCA) and contact pressure (gCP), were assessed at rest,15°,30°,45°, and maximum angle of glenohumeral abduction.

RESULTS

The PSRCT resulted in a significant decrease of gAA along with an increase in SM, cDF, and gCP (P<.001, respectively). SCR did not restore native gAA (P<.001), however, SM was significantly reduced (P<.001). Further, SCR significantly reduced deltoid forces at 30° (P=.007) and 45° of abduction (P=.007) when compared to the PSRCT. SCR did not restore native cDF at 30°(P=.015), 45°(P<.001), and maximum angle (P<.001) of glenohumeral abduction. Compared to the PSRCT, SCR resulted in a significant decrease of gCP at 15°(P=.008), 30°(P=.002), and 45°(P=.006). However, SCR did not completely restore native gCP at 45° (P=.038) and maximum abduction angle (P=.014).

CONCLUSION

In this dynamic shoulder model, SCR only partially restored native glenohumeral joint loads. However, SCR significantly decreased glenohumeral contact pressure, cumulative deltoid forces, and superior migration, while increasing abduction motion, when compared to the posterosuperior rotator cuff tear.

CLINICAL RELEVANCE

These observations raise concerns regarding the true joint preserving potential of SCR for an irreparable posterosuperior rotator cuff tear, along with its ability to delay progression of cuff tear arthropathy and eventual conversion to reverse shoulder arthroplasty.

Biomechanical outcomes of superior capsular reconstruction for irreparable rotator cuff tears by different graft materials-a systematic review and meta-analysis

Background

Irreparable rotator cuff tears (IRCT) are defined as defects that cannot be repaired due to tendon retraction, fat infiltration, or muscle atrophy. One surgical remedy for IRCT is superior capsular reconstruction (SCR), which fixes graft materials between the larger tuberosity and the superior glenoid.

Patients and methods

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) criteria were followed for conducting the systematic review and meta-analysis. From their inception until February 25, 2022, Pubmed, Embase, and Cochrane Library's electronic databases were searched. Studies using cadavers on SCR for IRCT were also included. The humeral head's superior translation and subacromial peak contact pressure were the primary outcomes. The humeral head's anteroposterior translation, the kind of graft material used, its size, and the deltoid load were the secondary outcomes.

Results

After eliminating duplicates from the search results, 1,443 unique articles remained, and 20 papers were finally included in the quantitative research. In 14 investigations, the enhanced superior translation of the humeral head was documented in IRCTs. In 13 studies, a considerable improvement following SCR was found, especially when using fascia lata (FL), which could achieve more translation restraints than human dermal allograft (HDA) and long head of bicep tendon (LHBT). Six investigations reported a subacromial peak contact pressure increase in IRCTs, which could be rectified by SCR, and these studies found a substantial increase in this pressure. The results of the reduction in subacromial peak contact pressure remained consistent regardless of the graft material utilized for SCR. While there was a statistically significant difference in the change of graft material length between FL and HDA, the change in graft material thickness between FL and HDA was not significant. The humeral head's anterior-posterior translation was rising in IRCTs and could be returned to its original state with SCR. In five investigations, IRCTs caused a significant increase in deltoid force. Furthermore, only one study showed that SCR significantly decreased deltoid force.

Conclusion

With IRCT, SCR might significantly decrease the glenohumeral joint's superior and anterior-posterior stability. Despite the risks for donor-site morbidity and the longer recovery time, FL is still the best current option for SCR.