The effect of platelet-rich fibrin, platelet-rich plasma, and concentrated growth factor in the repair of full thickness rotator cuff tears

BACKGROUND

Rotator cuff lesions rank among the prevalent causes of shoulder pain. Combining surgical interventions with growth factors, scaffolds, and stem cell therapies can effectively decrease the likelihood of rotator cuff repair recurrence. Platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and concentrated growth factor (CGF), isolated from blood and rich in growth factors, have a critical role in cell migration, cell proliferation, and angiogenesis during the tissue regeneration process. Investigations have further substantiated the beneficial impact of PRP and PRF on the biomechanical and histologic attributes of the tendon-bone interface. We aimed to investigate the effectiveness of CGF compared with PRF and PRP in the repair of rotator cuff lesions as a new treatment strategy.

METHODS

Incision was performed on both shoulder regions of 21 adult rabbits. After 8 weeks, both shoulders of the rabbits were repaired by suturing. PRF and CGF were administered to 2 separate groups along with the repair. Tissues were collected for biomechanical measurements and histologic evaluations.

RESULTS

Histologically, CGF, PRF, and PRP showed similar results to the healthy control group. The level of improvement was significant in the PRF and PRP groups. In the PRF group, the distribution of Ki67 (+), CD31 (+), and CD34 (+) cells was determined intensely in the tendon-bone junction regions. Apoptotic cells increased significantly in the repair group compared with the healthy group, whereas fewer apoptotic cells were found in the PRF-, PRP-, and CGF-applied groups. In the biomechanical results, no statistical difference was recorded among the groups.

CONCLUSION

The use of PRF, PRP, and CGF in rotator cuff repair shows promise in shortening the treatment period and preventing the recurrence of rotator cuff lesions.

Fibroblast Growth Factor Soaked Collagen Membrane Shows No Biomechanical or Histological Advantages in the Treatment of Chronic Rotator Cuff Tears in a Rabbit Model

PURPOSE

To investigate the histological and biomechanical effects of a fibroblast growth factor (FGF-2)-soaked collagen membrane used to treat a full-thickness chronic rotator cuff (RC) rupture in a rabbit model.

METHODS

Forty-eight shoulders from 24 rabbits were used. At the beginning of the procedure, 8 rabbits were killed to assess the control group (Group IT) with intact tendons. To establish a chronic RC tear model, a full-thickness subscapularis tear was created on both shoulders of the remaining 16 rabbits and left for 3 months. The transosseous mattress suture technique was used to repair tears in the left shoulder (Group R). The tears in the right shoulder (Group CM) were treated using the same approach, with an FGF-soaked collagen membrane inserted and sutured over the repair site. Three months after the procedure, all rabbits were killed. Biomechanical testing was performed on the tendons to determine failure load, linear stiffness, elongation intervals, and displacement. Histologically, the modified Watkins score was used to evaluate tendon-bone healing.

RESULTS

There was no significant difference among the three groups in terms of failure load, displacement, linear stiffness, and elongation (P > .05). The total modified Watkins score was not affected by applying the FGF-soaked collagen membrane to the repair site (P > .05). Fibrocytes, parallel cells, large-diameter fibers, and the total modified Watkins score were significantly lower in both repair groups when compared to the intact tendon group (P < .05).

CONCLUSIONS

In addition to tendon repair, FGF-2 soaked collagen membrane -application at the repair site provides neither biomechanical nor histological advantages in the treatment of chronic RC tears.

CLINICAL RELEVANCE

FGF-soaked collagen membrane augmentation provides no impact on the chronic RC tear healing tissue. The need to investigate alternative methods that may have a positive effect on healing in chronic RC repairs continues.

Three-Dimensional Finite Element Analysis of a Notched Insert Design for Reverse Total Shoulder Arthroplasty to Prevent Scapular Notching

Purpose

Reverse total shoulder arthroplasty (RSA) is an effective treatment option for rotator cuff arthropathy. Scapular notching following RSA remains a major complication and has a high incidence. This finite element analysis (FEA) study provides a future reference for the optimal design of the insert component of RSA. This study aims to clarify the effect of a new design RSA with a notched insert on the range of adduction, scapular notching, and stress variation of its insert component using three-dimensional (3D) FEA.

Methods

3D nominal Grammont-type monobloc RSA implant components are modeled on the sawbones glenohumeral joint. The polyethylene insert is redesigned with notching of the inferior part. The comparison of standard and notched designs was performed by FEA for stress pressure of scapular notching and the degree of adduction. 3D mesh models are created for stress analysis to compare the results between standard and notched inserts for the adduction.

Results

The redesigned notched inserts had an additional ~ 11.2° on adduction and prevented scapular notching. The stress analysis results for the notched insert design were lower than the standard ones (4.7 vs 22.4 Kpa).

Conclusions

Notched insert design of Grammont-type RSA could provide additional adduction with lower stress on the glenoid, leading to less scapular notching. Further experimental and clinical studies on different RSA types are needed to verify this effect.

Study Design

Basic Science Study; Biomechanics and Computer Modeling.

Is coracoclavicular ossification a complication or a good prognostic factor after surgical treatment of acromioclavicular joint injury?

Background

The purpose of this study was to investigate whether heterotopic ossification (HO) in the coracoclavicular (CC) space after surgical treatment of acromioclavicular joint (ACJ) injury is a complication or a sign of good prognosis.

Methods

Fifty-nine consecutive patients who underwent CC reconstruction with or without augmentation of the ACJ for acute ACJ injuries were analyzed. Postoperative American Shoulder and Elbow Surgeons (ASES) score, Constant score (CS), subjective shoulder value (SSV), and visual analog scale (VAS) results were evaluated. For radiological evaluation, HO was evaluated, and CC distances were measured.

Results

Fifty-one patients (11 women and 40 men; mean age, 36 years [range, 17-68 years]) were evaluated after a mean follow-up of 3 years (range, 2-8 years). The mean ASES score at the follow-up was 82.73 (range, 51.6-100), mean CS was 85 (range, 50-100), mean SSV was 80 (range, 40-100), and mean VAS was 1.9 (range, 0-5). It was observed that the clinical outcomes (ASES, CS, SSV, VAS) of patients who developed ossification in the CC space were better than those who did not although it was not statistically significant. No statistically significant differences were found in the clinical outcomes (ASES, CS, SSV, VAS) between patients who underwent CC reconstruction without augmentation of the ACJ and those who were combined (P > .05).

Conclusion

HO in the CC space is a common finding following AC joint fixation injury. We suggest that HO is not a complication and might possibly have positive effects on clinical outcomes.

Three dimensional patient-specific guides for guide pin positioning in reverse shoulder arthroplasty: An experimental study on different glenoid types

INTRODUCTION

Incorrect positioning is one of the main factors for glenoid component loosening in reverse shoulder arthroplasty and component placement can be challenging. This study aimed to assess whether Patient-Specific Instrumentation (PSI) provides better guide pin positioning accuracy and is superior to standard guided and freehand instrumentation methods in cases of glenoid bone deformity.

MATERIALS AND METHODS

Based on the Walch classification, five different scapula types were acquired by computed tomography (CT). For each type, two different surgeons placed a guide pin into the scapula using three different methods: freehand method, conventional non-patient-specific guide, and PSI guide. Each method was repeated five times by both surgeons. In these experiments, a total of 150 samples of scapula models were used (5 × 2 × 3 × 5 = 150). Post-operative CT scans of the samples with the guide pin were digitally assessed and the accuracy of the pin placement was determined by comparison to the preoperative planning on a three-dimensional (3D) model.

RESULTS

The PSI method showed accuracies to the preoperative plan of 2.68 (SD 2.10) degrees for version angle (p < .05), 2.59 (SD 2.68) degrees for inclination angle (p < .05), and 1.55 (SD 1.26) mm for entry point offset (p < .05). The mean and standard deviation errors compared to planned values of version angle, inclination angle, and entry point offset were statistically significant for the PSI method for the type C defected glenoid and non-arthritic glenoid.

CONCLUSION

Using the PSI guide created by an image processing software tool for guide pin positioning showed advantages in glenoid component positioning over other methods, for defected and intact glenoid types, but correlation with clinical outcomes should be examined.

Arthroscopic coracoclavicular button fixation versus anatomic locking plate fixation for unstable distal clavicular fractures

Hypothesis

Neer type II distal clavicle fractures are unstable and associated with high nonunion rates. The aim of this retrospective study was to compare the clinical and radiographic outcomes of anatomic locking plate fixation and arthroscopic coracoclavicular button fixation for unstable distal clavicle fractures.

Methods

Forty-seven patients with Neer type II distal clavicle fractures were treated surgically using either anatomic locking plate fixation (group 1, n = 20) or all arthroscopic coracoclavicular button fixation (group 2, n = 27) between 2012 and 2019 in 2 centers. Clinical and radiographic outcomes after an average follow-up period of 49 months for group 1 and 32 months for group 2 were assessed using the American Shoulder and Elbow Surgeons Shoulder score, Constant-Murley score, visual analog scale score and X-rays.

Results

At the final follow-up, the mean American Shoulder and Elbow Surgeons Shoulder score, Constant-Murley score, and visual analog scale score for group 1 and group 2 were 92.5 ± 3.9 (range 88.3-98.3), 93.6 ± 4.0 (range 90-100), and 0.6 ± 0.6 (range 0-2) and 95 ± 3.3 (range 86.6-100), 96.2 ± 3.0 (range 88-100), and 0.4 ± 0.5 (range 0-1), respectively (P = .32, P = .15, and P = .59, respectively). At the final follow-up, acceptable reduction and bone healing were achieved in all patients. All patients in both groups were able to resume work as well as sports activities. Postoperative complications included 1 case of acromioclavicular joint arthritis and 1 case of screw penetration in group 1 and 2 cases of coracoid process fracture that did not require additional surgery in group 2. Five patients underwent hardware removal owing to skin irritation and dissatisfaction with the cosmetic appearance in group 1.

Conclusion

Both distal anatomic locking plate fixation and arthroscopic coracoclavicular button fixation provide satisfactory functional and radiological outcomes. Both procedures can be used to treat distal clavicle fractures because they have a minimal risk of complications and present similar, high union rates.

Repair versus biceps tenodesis for the slap tears: A systematic review

PURPOSE

The ideal treatment algorithm is still controversial for Superior Labral Anterior-Posterior (SLAP) tears. In this systematic review, we aimed to clarify and ascertain which treatment modality is effective and more usable in which conditions.

METHODS

In this systematic review, we used the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines established for systematic reviews and meta-analysis. "SLAP or Superior Labral Anterior-Posterior" and "biceps tenodesis" search terms were used in The Cochrane Library database and Pubmed from their inception to the 30th of September 2020. A total of 2326 titles were screened and 2069 articles were removed because of their ineligibility. Full texts of 14 studies were screened and finally, six were suitable for the present systematic review. Demographic details and study characteristics, patient satisfaction, functional outcomes, return to preinjury sports level, reoperation, stiffness, sling time and rehabilitation protocols were reviewed and compared between SLAP repair and biceps tenodesis groups.

RESULTS

A total of 2326 titles were screened and six studies were detected eligible. Results of 287 patients (SLAP repair: 160, Biceps Tenodesis: 127) were reviewed in included six studies. Biceps tenodesis was showed as more satisfied technique in four of the studies but the statistical comparing results of two groups were not significantly different in each study. Different functional scoring systems used in the studies were not statistically significantly different between the groups. The percentage of return to sport and preinjury level is higher in biceps tenodesis in the five studies. The total reoperation rate for SLAP repair was 19/160 (12%) and biceps tenodesis was 7/127 (6%).

CONCLUSION

The biceps tenodesis has a higher return to preinjury sports level, higher patient satisfaction and lower reoperation rates but functional scores are similar between SLAP repair groups in patients with SLAP tear.

All arthroscopic coracoclavicular button fixation is efficient for Neer type II distal clavicle fractures

PURPOSE

Neer type II distal clavicle fractures are associated with a high rate of non-union or malunion due to impaired coracoclavicular ligament stability. The purpose of this study was to assess the clinical and radiological outcomes of arthroscopically assisted indirect osteosynthesis for type II distal clavicle fractures using a cortical suture button device.

METHODS

Seventeen patients Neer type II fractures of the distal clavicle were treated surgically using cortical suture button fixation between 2012 and 2017. The clinical and radiological results were assessed using the American Shoulder and Elbow Surgeons Shoulder Score (ASES), Constant-Murley score and visual analogue scale (VAS) score.

RESULTS

Anatomic reduction and bone healing were achieved in all patients at the final follow-up. The median age of the patients was 31 years (range 19-57). The mean follow-up was 25.9 months (range 14-64). The average delay before surgery was 2 days (range 1-4). At the final follow-up, the mean ASES, Constant-Murley score and VAS score were 92.6 ± 3.2 (range 84.9-96.6), 96.2 ± 2.4 (range 92-100) and 0.47 ± 0.51 (range 0-1), respectively. All patients were able to resume work as well as sport activities. The postoperative complications included two coracoid process fractures, and none of the patients required additional surgery related to the index procedure.

CONCLUSION

All arthroscopic coracoclavicular button fixation of Neer type II distal clavicle fractures would provide sufficient stability and union with satisfactory radiological and clinical outcomes. This arthroscopic fixation technique would be more efficient than other osteosynthesis methods because it is a minimally invasive surgery with a low complication rate.

LEVEL OF EVIDENCE

III.

Do Techniques for Hill-Sachs Remplissage Matter in Terms of Functional and Radiological Outcomes?

Background:

Different techniques are used for the remplissage procedure, including the double-pulley and mattress suture techniques. Both techniques have shown good results; however, it is unclear if one technique is superior.

Hypothesis:

The remplissage procedure using the double-pulley technique with 2 anchors would have superior functional and radiological outcomes compared with the mattress suture technique with a single anchor.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

This study included patients with anterior shoulder instability who were treated using arthroscopic Bankart repair combined with remplissage between 2012 and 2017. A structured questionnaire was used to gather information on the following metrics: Instability Severity Index Score, hyperlaxity, Sugaya index, presence of a Hill-Sachs defect, number of dislocations before surgery, sports participation, radiological measurement of the Hill-Sachs lesion, postoperative range of motion in both shoulders, Rowe score, Walch-Duplay score, American Shoulder and Elbow Surgeons score, and Filling Index Score of Remplissage grade according to magnetic resonance imaging scans at the last follow-up.

Results:

There were 41 patients included with a mean age of 30 ± 7 years who underwent the Hill-Sachs remplissage procedure using the double-pulley technique with 2 anchors (n = 21; group DA) or the mattress suture technique with a single anchor (n = 20; group SA). At the final follow-up, there were no significant differences between the groups regarding the Instability Severity Index Score (P = .134), the Sugaya index (P = .538), sports participation (P = .41), the radiological measurement of the Hill-Sachs lesion (P = .803), or the Rowe score (P = .182). However, there were significant differences between the groups in the Walch-Duplay score (P = .012), American Shoulder and Elbow Surgeons score (P = .005), and Filling Index Score of Remplissage grade (P = .015), favoring group DA, as well as differences in external rotation in a neutral position (external rotation loss: 9° ± 3° [group SA] vs 12° ± 3° [group DA]; P = .003) and at 90° of abduction (external rotation loss: 8° ± 3° [group SA] vs 11° ± 3° [group DA]; P = .006), favoring group SA.

Conclusion:

In the remplissage procedure, the double-pulley technique provided better filling of the lesion and improvement in functional scores, but external rotation was limited compared with the mattress suture technique.

The Role of Deadlifts in Distal Biceps Brachii Tendon Ruptures: An Alternative Mechanism Described With YouTube Videos

BACKGROUND

The classic injury mechanism of a distal biceps brachii tendon rupture (DBBTR) is eccentric loading to the flexed elbow when the forearm is supinated.

PURPOSE

To determine alternative mechanisms of a DBBTR in powerlifting sports, particularly in deadlift competitions, with the use of YouTube videos.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

A search on YouTube was performed using the search terms "distal biceps tendon rupture" and "distal biceps tendon injury" combined with "competition," "deadlift," and "powerlifting." The videos underwent an evaluation for accuracy by 3 surgeons according to predetermined criteria. Type of sports activity, participant sex, side of the injury, and arm positions at the time of the injury were recorded.

RESULTS

Among the videos reviewed, 35 injuries were found appropriate for an evaluation. All participants were male. The majority of the injuries (n = 25) were observed during the deadlift. Only in 1 deadlift injury were both forearms in supination. In the remaining deadlift injuries (n = 24), all elbows were in extension, with 1 forearm in supination and the other in pronation. Among the deadlift injuries in the mixed-grip position, all ruptures occurred in a supinated extremity: 25% (n = 6) of ruptures occurred on the right side, and 75% (n = 18) of ruptures occurred on the left side; this was a significant difference (P = .014).

CONCLUSION

We described an alternative mechanism for a DBBTR, namely, eccentric loading to an extended elbow when the forearm is supinated during the deadlift. As all the ruptures occurred in a supinated extremity, holding the bar with both forearms in pronation may prevent or decrease the risk of ruptures during the deadlift.

An unusual injury of pediatric both forearm fractures: Distraction epiphysiolysis: A case report

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IM K-wire implementation is first choice at pediatric both forearm fractures.

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The biggest concern about transphyseal transmission of the K-wire is physeal arrest.

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Physeal arrest could not be shown literature in transphyseal K-wire implementation.

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Distal of the physis line, a more suitable place for the entry point of the k-wire.

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Transphyseal application can prevent from distraction epiphysiolysis.

Introduction and importance

Pediatric both forearm fractures are one of the common traumas we encounter in clinical practice. We aimed to show a complication not shown in the literature, its possible cause and management of this complication in the surgery of these fractures.

Case presentation

9 years old girl applied to emergency orthopedics unit after fall. Both forearm fracture was appeared after X-ray. Due to reduction loss in the control X-ray of the first week, closed reduction and intramedullary K wire were planned. The prebent K-wire was tried to be sent as intramedullary. While attempting to advance the K-wire, loss of intramedullary resistance was felt. When controlled with fluoroscopy, type 1 epiphysiolysis was observed in the distal radius. Open anatomical reduction was performed on distal radius epiphysis. Two K wires were placed so that crossed the physis line. In 2-year follow-up, there was no length discrepancy or limitation of movement between the left and right radius.

Clinical discussion

Intramedullary fixation is first choice for surgery in pediatric both forearm fractures. There are 2 opinions for K-wire entering point: proximal and distal of physis. The biggest concern about transphyseal transmission of the K wire is that this conduction may cause physeal damage or arrest. However, physeal damage or arrest could not be shown in the literature. On the other hand, transphyseal application provides convenience in terms of surgical applicability.

Conclusion

In our opinion, it will be more appropriate and safe to send the K wire transphyseal over the styloid for pediatric population have both forearm fractures.

Tear Completion Versus In Situ Repair for 50% Partial-Thickness Bursal-Side Rotator Cuff Tears: A Biomechanical and Histological Study in an Animal Model

BACKGROUND

Tear completion followed by repair (TCR) and in situ repair (ISR) have been widely used for bursal-side partial-thickness rotator cuff tears (PTRCTs). Both techniques have shown favorable results; however, controversy continues in terms of the best management.

PURPOSE

To compare the histological and biomechanical outcomes of these 2 techniques for 50% partial-thickness bursal-side rotator cuff tear repair in a rabbit model.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 27 rabbits were used in this experimental study. Seven rabbits were sacrificed at the beginning of the study to form an intact tendon control group. A chronic 50% partial-thickness bursal-side tear model was created in 20 rabbits, and 5 rabbits were sacrificed for biomechanical testing of chronic partial-thickness tears (control group) without repair. In 15 rabbits, partial-thickness tears were repaired after 8 weeks. Partial-thickness tears in the right shoulders were completed to full thickness and repaired; in contrast, left shoulders were repaired in situ. All rabbits were euthanized 8 weeks after the repair. The tendons were tested biomechanically for ultimate failure, linear stiffness, and displacement. Histological evaluations of tendon-to-bone healing were performed via the modified Watkins score.

RESULTS

Macroscopically, all repaired tendons were attached to the greater tuberosity. The TCR group had a higher failure load than the ISR group, with mean values of 140.4 ± 13.8 N and 108.1 ± 16.6 N, respectively (P = .001). The modified Watkins score was significantly higher in the TCR group (23.5; range, 22-27) than in the ISR group (19.5; range, 16-22) (P = .009).

CONCLUSION

Both repair techniques are effective for 50% partial-thickness bursal-side rotator cuff tears; however, TCR yields significantly superior biomechanical and histological characteristics compared with ISR.

CLINICAL RELEVANCE

Tear completion and repair technique may increase tendon-to-bone healing and thereby reduce re-rupture rate in the partial thickness bursal side rotator cuff tears.

Biomechanical comparison of humeral nails with different distal locking mechanisms: Insafelock nails versus conventional locking nails

Objective

The aim of this study was to compare the biomechanical resistance to rotational and axial forces of a conventional locking nail with a newly designed intramedullary humeral nail developed for humeral shaft fractures with a secure locking mechanism through the distal part of the nail.

Methods

InSafeLOCK humeral nail system (group 1, TST, Istanbul, Turkey) and Expert humeral nail system (group 2, DePuy Synthes, Bettlach, Switzerland) of the same size (9 × 300 mm) were examined. In total, 24 fourth-generation humerus sawbones were used in the experiment. Osteotomy was performed at the humerus shaft, and a defect was created by removing 1 cm of bone. After pre-loading 5000 cycles at a frequency of 2 Hz and a force of 50–250 N for axial loading and 5000 torsion torques between 0.5 Nm and 6.5 Nm at a 2 Hz frequency for torsional loading, the failure load values of each load were recorded. Distal interlocking was performed with an endopin in group 1, while a double cortex screw was used in group 2.

Results

All samples successfully passed the cyclic loading. The initial and final stiffness values were similar between the groups after axial loading (p = 0.873 and p = 0.522, respectively). The mean axial failure load values in groups 1 and 2 were 2627 ± 164 N and 7141 ± 1491 N, respectively. A significant difference was found in the axial failure load values (p = 0.004). Significant differences were observed between the initial and final torsional stiffness between the two groups (p = 0.004 and p = 0.004, respectively). No significant difference was found in the failure load values after torsional loading (11791 ± 2055 N.mm and 16997 ± 5440 N.mm) (p = 0.055).

Conclusion

These results provide a biomechanical demonstration of the adequate stability of both nails after axial and rotational loading. The reliability of the newly developed InSafeLOCK humeral nail system, which does not require fluoroscopic control and an additional incision for distal locking, supports its use in the clinic.

Late diagnosis of subcoracoid type 6 AC dislocation: A case report

Acromioclavicular (AC) dislocation is a common type of shoulder injury. Although the incidence of acromioclavicular dislocation is frequent, there are different opinions regarding the treatment. Many different techniques have been proposed for the surgical treatment of AC dislocations, but all these methods have been questioned from different angles, and the gold standard in terms of treatment has not yet been determined. There are six types described by Rockwood et al. and type 6 has two types: subacromial and subcoracoid. Subcoracoid AC Type 6 dislocations are seen very rarely and difficult to diagnose in initial clinical findings or can be simply overlooked due to associated more serious injuries which take more attention. The mechanism of injury of a type 6 AC dislocation is hyperabduction and external rotation of the shoulder. A small number of type 6 subcoracoid AC dislocations have formerly been reported and apart from one case all of them were acutely diagnosed and treated with open reduction and internal fixation. In this paper, we report a case of late diagnosis of subcoracoid type 6 AC dislocation, along with its rare and previously unreported surgical management.

Comparison of two different superior capsule reconstruction methods in the treatment of chronic irreparable rotator cuff tears: a biomechanical and histologic study in rabbit models

BACKGROUND

In the treatment of irreparable rotary cuff (RC) tears, the superior capsule of the shoulder is reconstructed using tensor fascia lata (TFL) or several allografts to prevent progressive joint degeneration. This study compared the healing qualities of acellular human dermal graft (HDG) and the TFL autograft in superior capsule reconstruction (SCR) from biomechanical and histologic perspectives.

METHODS

Chronic retracted RC tear models were created bilaterally in 9 rabbits, and 7 rabbits with intact RC were used as a control group. SCR was performed 8 weeks after the tear using HDG in right shoulders and TFL in left shoulders. At 12 weeks after SCR, 2 shoulders from each experimental group were investigated for histologic healing, and 7 samples from the experimental and control groups were biomechanically tested.

RESULTS

Complete healing was observed macroscopically in the glenoid and humeral sides of both groups. No difference was observed in the enthesis maturation scores between the experimental groups. Collagen fiber density was higher and the orientation was better in TFL group. Inflammatory cell infiltration was not seen in the TFL group, but inflammatory cell infiltration was pronounced in the HDG group. The mean pullout strengths of the TFL group, HDG group, and intact RC group were 139.7 ± 40.5 N, 123.9 ± 47.9 N, and 105.1 ± 11.8 N (P = .187), respectively. The mean stiffness values (P = .711), yield forces (P = .404), and displacements (P = .135) were also statistically not different between the groups.

CONCLUSION

In SCR, the healing qualities of HDG and TFL were similar in rabbit models.

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.

Hip fractures in extremely old patients

AIMS

The purpose of this study was to report a less seen age-group (>90) of hip fractures and to assess the predictors of functional loss, complications and mortality.

METHODS

Thirty-two patients at a mean age of 92.8 (±2.7) were treated in a single institution and reported at a mean follow-up of 2.02 (±1.35) years.

RESULTS

Mortality was similar between proximal femoral nailing (PFN) and bipolar cemented hemiarthroplasty (BCH) in first year (p = 0.17) but significantly high in following years in BCH (p = 0.035) and patients with cardiac disease (p = 0.054).

CONCLUSION

Hip fractures are challenging in extremely old patients and associated with increased mortality and disability.