Relationship between scapular body morphology and rotator cuff tears: a threedimensional computed tomography study.

The purpose of this study was to identify the relationship between scapula morphology and rotator cuff tears (RCT). Hundred seventeen shoulders with and 87 shoulders without RCTs were included in this retrospective study. The critical shoulder angle (CSA) and lateral acromion angle in the coronal view, and the acromial coverage angle (ACA) and coracoid and scapular spine angle (CSSA) in the sagittal view were evaluated using 3-dimensional computed tomography.

Range of Motion and Muscle Strength Changes in Japanese Professional Pitchers During the Baseball Season.

Background: There are no studies examining changes in the physical function throughout the baseball season in Japanese professional players. We examined the range of motion (ROM) and muscle strength changes in professional baseball pitchers as the season progresses.

Materials And Methods: Five professional baseball pitchers were included.

Long-term conservative treatment outcomes for midshaft clavicle fractures: a 10-to-30-year follow-up.

Background: Few reports exist on the long-term outcomes of midshaft clavicle fracture conservative treatments. Therefore, this study investigated the long-term outcome of this treatment in patients with midshaft clavicle fractures.

Methods: Patients were treated conservatively for midshaft clavicle fractures with a figure-of-eight bandage between 10 and 30 years ago.

Factors affecting stress shielding and osteolysis after reverse shoulder arthroplasty: A multicenter study in a Japanese population.

Background: Stress shielding and osteolysis around the humeral stem after reverse shoulder arthroplasty causes loosening and periprosthetic fractures and reduces bone stock during revision surgery. In Japanese patients, who have relatively small bodies, different characteristics may exist regarding the occurrence of these changes compared with the characteristics of Westerners, who have relatively larger frames. The purpose of this multicenter study was to investigate the incidence and clarify the predictors of stress shielding and osteolysis in Japanese individuals who underwent reverse shoulder arthroplasty.

Return to sports after arthroscopic Bankart repair in teenage athletes: a retrospective cohort study.

Background: Anterior shoulder instability is frequent among young athletes. Surgical treatment for this injury aims to facilitate an early return to sports (RTS). However, the rate of recurrent instability after surgery is reportedly high among young patients, and it is unclear whether surgery ensures satisfactory RTS.

Clinical outcomes and tendon lengthening after arthroscopic rotator cuff repair.

Background: There is a phenomenon in which the tendon appears to increase the length after rotator cuff repair. However, it is unclear in which cases tendon lengthening occurs and how the degree of lengthening affects the surgical outcome. This study aimed to evaluate preoperative and postoperative musculotendinous junction (MTJ) and tendon length on magnetic resonance imaging and assess the postoperative tendon lengthening and its impact on postoperative outcomes.

Prevalence of Rotator Cuff Tears Among Older Tennis Players and Its Impact on Clinical Findings and Shoulder Function.

Context: Tennis is a noncontact sport playable at an individual's own pace. Thus, it is popular among the older adults. It is known that older adults often suffer from rotator cuff tears (RCTs), which may affect tennis activity.

Evaluation of subscapularis tendon tears of the anterosuperior aspect using radial-sequence magnetic resonance imaging.

Background: Magnetic resonance imaging (MRI) is widely used to diagnose subscapularis tendon tears; however, it is difficult to assess the anterosuperior aspect of these tears. Radial-sequence MRI can reveal the fiber components of the anterosuperior aspect, from perpendicular, by overcoming the partial volume effect. We aimed to classify the insertion of subscapularis tendon tears on radial-sequence MRI and determine the effectiveness of radial-sequence MRI for subscapularis tendon tear assessments.

Return to sports after arthroscopic bankart repair on the dominant shoulder in overhead athletes.

Background: Arthroscopic Bankart repair (ABR) yields good results in young athletes with anterior shoulder instability. However, the treatment for overhead athletes is challenging because recovery of range of motion is necessary for return to play and repeated shoulder motion may lead to recurrent instability. The aim of this study was to investigate the clinical outcomes and return to sports after ABR on the dominant shoulder in overhead athletes.

Shoulder ranges of motion and humeral torsions of injured baseball players have different characteristics depending on their pitching sides.

Background: Right- and left-side throwers in baseball may have different shoulder conditions and throwing biomechanics. This study aimed to compare the passive range of motion, humeral torsion, and clinical findings between right- and left-handed throwers who sustained throwing shoulder injuries and confirm the differences in the characteristics between throwing sides.

Methods: A total of 52 pitchers diagnosed with throwing shoulder injuries were included in this study: 27 patients were right-side throwers (R group), and 25 were left-side throwers (L group).

Effectiveness of measuring tension during arthroscopic rotator cuff repair.

Purpose: Arthroscopic rotator cuff repair (ARCR) for relatively small rotator cuff tears (RCTs) has shown promising results; however, such surgery for larger tears often results in failure and poor clinical outcomes. One cause of failure is over-tension at the repair site that will be covered with the tendon stump. Reports on the clinical outcomes using ARCR with tension ≤ 30 N are lacking.

Arthroscopic Rotator Cuff Repair With Muscle Advancement and Artificial Biodegradable Sheet Reinforcement for Massive Rotator Cuff Tears.

Background: Because high failure rates have frequently been reported after arthroscopic rotator cuff repair (ARCR) of massive rotator cuff tears (mRCTs), we introduced the technique of ARCR with supraspinatus and infraspinatus muscle advancement (MA). However, for cases where the original footprint cannot be completely covered, additional surgery using an approved artificial biomaterial is performed.

Purpose: To investigate the postoperative clinical outcomes and failure rate after MA-ARCR, with and without our reinforcement technique.

Factors associated with pain in nonsurgically treated rotator cuff tears -A study with magnetic resonance imaging.

Background: In rotator cuff tears, some cases become asymptomatic with nonsurgical treatment, others remain symptomatic. The purpose of this study was to identify factors associated with pain in nonsurgically treated rotator cuff tears using magnetic resonance imaging (MRI).

Methods: In total, 108 shoulders diagnosed with supraspinatus (SSP) tendon tears using MRI were nonsurgically treated, and MRI was repeated after more than a year.

Outcomes of arthroscopic rotator cuff repair with muscle advancement for massive rotator cuff tears.

Background: We performed arthroscopic rotator cuff repair (ARCR) combined with miniopen supraspinatus and infraspinatus muscle advancement for massive rotator cuff tears (RCTs) to decrease tension at the repair site with the goal of reduction of the failure rate. We evaluated the clinical outcomes and failure rate after this procedure.

Methods: This study included 47 patients diagnosed with chronic massive RCTs between October 2010 and March 2015.

Bone mineralization changes of the glenoid in shoulders with symptomatic rotator cuff tear.

Purpose: Computed tomography osteoabsorptiometry (CTO) is a method to analyze the stress distribution in joints by measuring the subchondral bone density. The purpose of this study was to evaluate the bone mineralization changes of the glenoid in shoulders with rotator cuff tears by CTO and to evaluate whether rotator cuff tears are associated with stress changes in the glenoid.

Methods: In total, 32 patients, who were diagnosed with unilateral rotator cuff tears and underwent arthroscopic rotator cuff repair, were enrolled in this study.

The prospective evaluation of changes in fatty infiltration and shoulder strength in nonsurgically treated rotator cuff tears.

Background: The purpose of this study was to evaluate the relationship of fatty infiltration in rotator cuff muscles and shoulder strength in rotator cuff tears and these changes during nonsurgical treatment.

Methods: Fifty-three shoulders from 47 patients (mean age: 69.9 years) diagnosed with rotator cuff tears by magnetic resonance imaging (MRI) were treated nonsurgically.

Monitoring of progression of nonsurgically treated rotator cuff tears by magnetic resonance imaging.

Background: Nonsurgically treated rotator cuff tears sometimes become irreparable in the lead up to surgical repair. The purposes of our study were to identify predictive factors in the progression of tear size, and determine the changes in tear location.

Methods: Eighty shoulders from 71 patients (mean age 69.

Rotator cuff regeneration using a bioabsorbable material with bone marrow-derived mesenchymal stem cells in a rabbit model.

Background: Rotator cuff regeneration using tissue engineering techniques is a challenging treatment in elderly patients with irreparable rotator cuff tears.

Hypothesis: A polyglycolic acid sheet scaffold with seeded mesenchymal stem cells (MSCs) may enhance the expression of type I collagen products and increase the mechanical strength of the regenerated tendon in vivo.

Study Design: Controlled laboratory study.

Tendon-bone insertion repair and regeneration using polyglycolic acid sheet in the rabbit rotator cuff injury model.

Background: The quality of tendons has considerable limitations regarding torn rotator cuff tendons. Tissue-engineering techniques using a biodegradable scaffold offer potential alternatives for recreating a valid tendon-to-bone interface.

Hypothesis: A polyglycolic acid (PGA) sheet could facilitate the regeneration of the rotator cuff tendon insertion in vivo.

Arthroscopic autologous bone graft with arthroscopic Bankart repair for a large bony defect lesion caused by recurrent shoulder dislocation.

Many clinicians believe that a large bony defect of the glenoid must be treated with bone grafting when a Bankart procedure is performed. Various types of bone graft, such as open bone graft, Eden-Hybinnette, J-bone graft, coracoid transfer, and Latarjet, have been used. These require open procedures that are difficult to perform arthroscopically.

Augmentation of tendon attachment to porous ceramics by bone marrow stromal cells in a rabbit model.

Tendon attachment to interconnected porous calcium hydroxyapatite ceramics (IP-CHA) with cultured bone marrow stromal cells (BMSC) was analysed. The purpose of this study was to evaluate whether BMSC in IP-CHA could augment the tendon attachment to IP-CHA histologically and biomechanically. Eighteen Japanese white rabbits were used.

Effects of interconnecting porous structure of hydroxyapatite ceramics on interface between grafted tendon and ceramics.

The purpose of this study was to evaluate histologically and biomechanically the interface between porous hydroxyapatite ceramics and a tendon grafted into ceramics, and to compare the interface in two ceramics with different porous structures: interconnected porous calcium hydroxyapatite ceramics (IP-CHA) with an effective porosity index (interpore diameter > 20 microm) of 63.6%, and porous calcium hydroxyapatite ceramics with less interconnection (HA-L) with an effective porosity index of 5.5%.