Recent biomechanical and clinical studies have demonstrated the effectiveness of suture button and pulley-type fixations for surgical treatment of acromioclavicular instability. Concerns remain that such procedures can "overconstrain" (overreduce the lateral clavicle in relation to the acromion to a nonphysiological position) the joint. Purpose/Hypothesis: The purpose of this study was to investigate the intra-articular pressure of native and reconstructed acromioclavicular (AC) joints in relation to the configuration of the joint. Anatomic (0 mm), overconstrained (-3 mm), and underconstrained (+3 mm) AC joint reconstructions were simulated. The hypothesis was that reconstructions using suture pulley systems do not increase the intra-articular pressure of the AC joint.

Controlled laboratory study.

Eleven fresh-frozen cadaveric shoulders were used in this study (mean age ± SD, 60.8 ± 6.7 years). Each specimen underwent radiographic analysis by using a Zanca view to determine the basic configuration of the AC joint. A pressure Tekscan sensor was inserted in the AC joint. A servohydraulic materials testing system was used for testing. The specimens were kept in the testing machine, and the native AC position was marked at 0 mm. This allowed moving the clavicle during the surgical procedure with reference to the native anatomic position. Intra-articular pressure in the native AC joint during cyclic loading (1000 cycles; 1 Hz) was measured. After native testing, the AC ligaments and coracoclavicular ligaments were cut and reconstructed using a cortical button technique. Anatomic, -3 mm, and +3 mm positions, relative to the acromion, were cyclically loaded, and intra-articular pressure was documented.

According to the AC joint classification of inclination, we identified five type 1 (46%), four type 2 (36%), one type 3 (9%), and one incongruous (9%) configurations. Changes in superior displacement across the 4 conditions were not statistically significant (0.5 ± 0.8 [native], 0.01 ± 0.00 [0 mm repair], 0.02 ± 0.02 [-3 mm repair], and 0.01 ± 0.01 [+3 mm repair]; P = .162). Before testing (time point 1), pressure in the -3 mm repair (62.9 ± 70.1) differed between the native state (11.3 ± 21.8; P = .042) and the +3 mm repair (7.1 ± 18.4; P = .023). All other changes at time points 2 (after cyclic loading unloaded) and 3 (after cyclic loading loaded) inpressure were not significant. ( P = .086 and .226, respectively).

AC joint reconstruction (within -3 to +3 mm of reduction) with a coracoclavicular suture button device does not significantly increase the intra-articular pressure of the AC joint after cyclic loading in our experimental cadaveric setup.

Recent biomechanical and clinical studies have demonstrated the effectiveness of suture button and pulley-type fixations for coracoclavicular reconstruction of the joint. Concerns remain that such procedures would "overconstrain" the joint because of the high rigidity of these pulley systems and the preservation of the lateral clavicle. This overconstraining may potentially result in pain at the lateral end of the clavicle, osteolysis, or a later increased risk of early osteoarthritis. Therefore, our results indicate that within a range of ±3 mm to the anatomic position, overconstraining may not result in a higher intra-articular pressure.

Studies on the results of arthroscopic repair of massive rotator cuff tears have reported widely varied prognoses. Among other factors, the sizable discrepancy can be attributable to the fact that the current definition of massive rotator cuff tearscovers an extensive area of tendons.

Functional and radiological results according to subgroups would show significant inter-subgroup differences preoperatively and postoperatively.

Cohort study; Level of evidence, 2.

A total of 104 patients who required arthroscopic repair for massive rotator cuff tears were prospectively evaluated. The patients were allocated into 3 groups according to tendon involvement as diagnosed by preoperative magnetic resonance imaging: group 1 (anterosuperior type involving the subscapularis and supraspinatus), group 2 (posterosuperior type involving the infraspinatus and supraspinatus), and group 3 (anteroposterior type involving the subscapularis, supraspinatus, and infraspinatus). We compared functional results (at 2 years postoperatively) and radiological findings (at 1 year postoperatively) for each group.

There were 34 patients in group 1, 54 in group 2, and 16 in group 3. In all 3 groups, functional results significantly improved after surgery. There were no statistically significant intergroup differences in functional results among the 3 groups. On the radiological evaluations, each group (groups 1, 2, and 3) showed a significantly different result in the preoperative acromiohumeral distance (AHD) (7.19, 5.44, and 5.22 mm, respectively), tear size (38.8, 39.3, and 46.4 mm, respectively), extent of retraction (33.9, 40.0, and 41.4 mm, respectively), postoperative AHD (8.92, 7.37, and 6.71 mm, respectively), and retear rate (23.5%, 51.9%, and 56.2%, respectively) ( P < .001 for all).

Massive rotator cuff tears can be divided into 3 types: anterosuperior (group 1), posterosuperior (group 2), and anteroposterior (group 3). Each group has distinctive characteristics and shows different results in the preoperative AHD, tear size, extent of retraction, postoperative AHD, and retear rate, which provide a reasonable basis for categorization. So far, massive rotator cuff tears have only been broadly defined, consequently being understood as a single category by many. However, to clearly understand and evaluate this injury, we suggest identifying differences within the category through proper subclassification.

Shoulder disorders are common in football players, with up to 50% of National Football League (NFL) recruits reporting a history of shoulder injuries. Superior labrum anterior-posterior (SLAP) tears are an entity with well-described detrimental effects on return to play in overhead-throwing athletes but with minimal data in contact athletes.

To identify the incidence, predisposing factors, and effect of SLAP tears in NFL athletes and prospects as well as the treatment patterns of NFL team physicians.

Descriptive epidemiology study.

This study was a comprehensive analysis of SLAP tears in elite football players using a dual approach: (1) SLAP injuries recorded in the NFL Injury Surveillance System from 2000 to 2014 were evaluated by player position, type of play, days/games lost, and surgical intervention; (2) NFL Scouting Combine athletes from 2003 to 2011 with prior SLAP repair were evaluated for draft success, and drafted athletes were compared with matched controls for career length and performance scores.

SLAP tears represented a small portion (3.1%) of shoulder injuries in NFL athletes from 2000 to 2014, occurring most commonly in offensive linemen (28%). Surgically treated SLAP tears (42%) resulted in more days missed than did nonoperatively managed tears (140.2 vs 21.5 days; P < .001) and more games missed (8.4 vs 2.6 games; P = .003). SLAP repairs were also rare in NFL Combine athletes (n = 25 of 2965 athletes), with most having been performed in offensive linemen (32%). As compared with control NFL Combine athletes without SLAP tears, those drafted into the NFL with prior SLAP repair played significantly fewer games (33.7 vs 48.3; P = .049) and had fewer game starts (19.6 vs 35.4; P = .036).

In this comprehensive analysis of SLAP tears in elite football players, it is clear that these injuries have the potential to cause significant detriment to an athlete's career.

Pectoralis minor (PM) tightness has been linked to pain and dysfunction of the shoulder joint secondary to anterior tilt and internal rotation of the scapula, thus causing secondary impingement of the subacromial space.

To describe outcomes pertaining to nonoperative and operative treatment via surgical release of the PM tendon for pathologic PM tightness in an active population.

Case series; Level of evidence, 4.

Over a 3-year period, a total of 46 patients were enrolled (mean age, 25.5 years; range, 18-33 years). Inclusion criteria consisted of symptomatic shoulder pain, limited range of overhead motion, inability to participate in overhead lifting activities, and examination findings consistent with scapular dysfunction secondary to a tight PM with tenderness to palpation of the PM tendon. All patients underwent a lengthy physical therapy and stretching program (mean, 11.4 months; range, 3-23 months), which was followed by serial examinations for resolution of symptoms and scapular tilt. Of the 46 patients, 6 (13%) were unable to adequately stretch the PM and underwent isolated mini-open PM release. Outcomes were assessed with scapula protraction measurements and pain scales as well as American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation (SANE), and visual analog scale (VAS) scores.

Forty of the 46 patients (87%) resolved the tight PM and scapular-mediated symptoms with a dedicated therapy program (pre- and posttreatment mean outcome scores: 58 and 91 [ASES], 50 and 90 [SANE], 4.9 and 0.8 [VAS]; P < .01 for all), but 6 patients were considered nonresponders (mean score, 48 [ASES], 40 [SANE], 5.9 [VAS]) and elected to have surgical PM release, with improved scores in all domains (mean score, 89 [ASES], 90.4 [SANE], 0.9 [VAS]; P < .01) at final follow-up of 26 months (range, 25-30 months). Additionally, protraction of the scapula improved from 1.2 to 0.3 cm in a mean midline measurement from the chest wall preoperatively to postoperatively ( P < .01), similar to results in nonoperative responders. No surgical complications were reported, and all patients returned to full activities.

In most patients, PM tightness can be successfully treated with a nonoperative focused PM stretching program. However, in refractory and pathologically tight PM cases, this series demonstrates predictable return to function with notable improvement in shoulder symptoms after surgical release of the PM. Additional research is necessary to evaluate the long-term efficacy of isolated PM treatment.

Massive rotator cuff tears (MRCTs) are usually chronic lesions with pronounced degenerative changes, where advanced fatty degeneration and atrophy can make the tear irreparable. Human mesenchymal stem cells (hMSCs) secrete a range of growth factors and vesicular systems, known as secretome, that mediates regenerative processes in tissues undergoing degeneration.

To study the effect of hMSC secretome on muscular degenerative changes and shoulder function on a rat MRCT model.

Controlled laboratory study.

A bilateral 2-tendon (supraspinatus and infraspinatus) section was performed to create an MRCT in a rat model. Forty-four Wistar-Han rats were randomly assigned to 6 groups: control group (sham surgery), lesion control group (MRCT), and 4 treated-lesion groups according to the site and periodicity of hMSC secretome injection: single local injection, multiple local injections, single systemic injection, and multiple systemic injections. Forelimb function was analyzed with the staircase test. Atrophy and fatty degeneration of the muscle were evaluated at 8 and 16 weeks after injury. A proteomic analysis was conducted to identify the molecules present in the hMSC secretome that can be associated with muscular degeneration prevention.

When untreated for 8 weeks, the MRCT rats exhibited a significantly higher fat content (0.73% ± 0.19%) compared with rats treated with a single local injection (0.21% ± 0.04%; P < .01) or multiple systemic injections (0.25% ± 0.10%; P < .05) of hMSCsecretome. At 16 weeks after injury, a protective effect of the secretome in the multiple systemic injections (0.62% ± 0.14%; P < .001), single local injection (0.76% ± 0.17%; P < .001), and multiple local injections (1.35% ± 0.21%; P < .05) was observed when compared with the untreated MRCT group (2.51% ± 0.42%). Regarding muscle atrophy, 8 weeks after injury, only the single local injection group (0.0993% ± 0.0036%) presented a significantly higher muscle mass than that of the untreated MRCT group (0.0794% ± 0.0047%; P < .05). Finally, the proteomic analysis revealed the presence of important proteins with muscle regeneration, namely, pigment epithelium-derived factor and follistatin.

The study data suggest that hMSC secretome effectively decreases the fatty degeneration and atrophy of the rotatorcuff muscles.

We describe a new approach for decreasing the characteristic muscle degeneration associated with chronicrotator cuff tears. This strategy is particularly important for patients whose tendon healing after later surgical repair could be compromised by the progressing degenerative changes. In addition, both precise intramuscular local injection and multiple systemicsecretome injections have been shown to be promising delivery forms for preventing muscle degeneration.

© 2016 The Author(s).

Tendinopathy is very common in the general population. There are increasing numbers of clinical studies referring toplatelet-rich plasma (PRP) and platelet-poor plasma (PPP) as treatments for tendinopathy.

To perform a meta-analysis of the outcomes of the PRP groups by preparation method and injection technique intendinopathy. To determine the clinical effectiveness of the preparations and to evaluate the effect of controls used in the studies reviewed.

Systematic review and meta-analysis.

The PubMed, EMBASE, CINAHL, and Medline databases were searched in March 2012, April 2014, and August 2015, and randomized controlled trials using autologous blood, PRP, PPP, or autologous conditioned plasma in tendinopathy with outcome measures of pain and follow-up time of 3 months were included in this review. Trials including surgery, tendon tears, and muscle or ligament injuries were excluded. Study quality was assessed using the Cochrane Collaboration risk-of-bias tool by 2 reviewers. Data were pooled using random-effects meta-analysis. The primary outcome measure was a change in pain intensity. Where more than 1 pain scale was included, a functional score was selected ahead of a visual analog scale score.

A total of 18 studies (1066 participants) were included. Eight studies were deemed to be at low risk of bias. The most significant outcomes in the PRP groups were seen in those treated with highly cellular leukocyte-rich PRP (LR-PRP) preparations: GPS kit (standardized mean difference [SMD], 35.75; 95% CI, 28.40-43.10), MyCells kit (SMD, 31.84; 95% CI, 17.56-46.13), Prosys kit (SMD, 42.99; 95% CI, 37.73-48.25), and unspecified LR-PRP (SMD, 34.62; 95% CI, 31.69-37.55). When the LR-PRP system types were grouped, there was a strongly positive effect (SMD, 36.38; 95% CI, 34.00-38.77) when compared with leukocyte-poor PRP (SMD, 26.77; 95% CI, 18.31-35.22). In assessing the control groups, there was no clear difference between different types of control injections: saline (SMD, 14.62; 95% CI, 10.74-18.50), local anesthetic (SMD, 15.00; 95% CI, 7.66-22.34), corticosteroid (SMD, 23.82; 95% CI, 10.74-18.50), or dry needling (SMD, 25.22; 95% CI, 21.27-29.16).

There is good evidence to support the use of a single injection of LR-PRP under ultrasound guidance in tendinopathy. Both the preparation and intratendinous injection technique of PRP appear to be of great clinical significance.

Many patients who are considering total joint arthroplasty, including hip, knee, and shoulder replacement, are concerned with their likelihood of returning to golf postoperatively as well as the effect that surgery will have on their game.

To review the existing literature on patients who have undergone major joint arthroplasty (hip, knee, and shoulder), to examine the effects of surgery on performance in golf, and to provide surgeon recommendations as related to participation in golfafter surgery. A brief review of the history and biomechanics of the golf swing is also provided.

Systematic review.

We performed a systematic review of the literature in the online Medline database, evaluating articles that contained the terms "golf" and "arthroplasty." Additionally, a web-based search evaluating clinical practice recommendations after joint arthroplastywas performed. The research was reviewed, and objective and anecdotal guidelines were formulated.

Total joint arthroplasty provided an improvement in pain during golfing activity, and most patients were able to return to sport with variable improvements in sport-specific outcomes.

In counseling patients regarding the return to golf after joint arthroplasty, it is our opinion, on the basis of our experience and those reported from others in the literature, that golfers undergoing total hip, knee, and shoulder arthroplasty can safely return to sport.