We hypothesised that diet-induced obesity (DIO) would result in inferior enthesis healing in a rat model of rotator cuff (RC) repair and that dietary intervention in the peri-operative period would improve enthesis healing. A total of 78 male Sprague-Dawley rats were divided into three weight-matched groups from weaning and fed either: control diet (CD), high-fat diet (HFD), or HFD until surgery, then CD thereafter (HF-CD). After 12 weeks, the left supraspinatus tendon was detached, followed by immediate surgical repair. At 2 and 12 weeks post-surgery, animals were culled, and RCs harvested for biomechanical and histological evaluation. Body composition and metabolic markers were assessed via DEXA and plasma analyses, respectively. DIO was established in the HFD and HF-CD groups before surgery and subsequently reversed in the HF-CD group after surgery. Histologically, the appearance of the repaired entheses was poorer in both the HFD and HF-CD groups compared with the CD group at 12 weeks after surgery, with semiquantitative scores of 6.2 (P<0.01), 4.98 (P<0.01), and 8.7 of 15, respectively. The repaired entheses in the HF-CD group had a significantly lower load to failure (P=0.03) at 12 weeks after surgery compared with the CD group, while the load to failure in the HFD group was low but not significantly different (P=0.10). Plasma leptin were negatively correlated with histology scores and load to failure at 12 weeks after surgery. DIO impaired enthesis healing in this rat RC repair model, with inferior biomechanical and histological outcomes. Restoring normal weight with dietary change after surgery did not improve healing outcomes. Circulating levels of leptin significantly correlated with poor healing outcomes. This pre-clinical rodent model demonstrates that obesity is a potentially modifiable factor that impairs RC healing and increases the risk of failure after RC surgery.
It is undetermined which factors predict return to work following arthroscopic rotator cuff repair. We aimed to identify which factors predicted return to work at any level, and return to pre-injury levels of work 6 months post-arthroscopic rotator cuff repair. Multiple logistic regression analysis of prospectively collected demographic, pre-injury, preoperative, and intraoperative data from 1502 consecutive primary arthroscopic rotator cuff repairs, performed by a single surgeon, was performed to identify independent predictors of return to work, and return to pre-injury levels of work respectively, 6 months post-surgery. Six months post-rotator cuff repair, 76% of patients returned to work (RTW), and 40% returned to pre-injury levels of work (Full-RTW). RTW at 6 months was likely if patients were still working after their injuries, but prior to surgery (Wald statistic [W]=55, p<0.0001), were stronger in internal rotation preoperatively (W=8, p=0.004), had full-thickness tears (W=9, p=0.002), and were female (W=5, p=0.030). Patients who achieved Full-RTW were likely to have worked less strenuously pre-injury (W=173, p<0.0001), worked more strenuously post-injury but pre-surgery (W=22, p<0.0001), had greater behind-the-back lift-off strength preoperatively (W=8, p=0.004), and had less passive external rotation range of motion preoperatively (W=5, p=0.034). Patients who were still working post-injury, but pre-surgery were 1.6-times more likely to RTW than patients who were not (p<0.0001). Patients who nominated their pre-injury level of work as “light” were 11-times more likely to achieve Full-RTW than those who nominated “strenuous” (p<0.0001). Six months post-rotator cuff repair, a higher patient-rated post-injury, but pre-surgery level of work was the strongest predictor of RTW. A lower patient-rated pre-injury level of work was the strongest predictor of Full-RTW. Greater preoperative subscapularis strength independently predicted both RTW, and Full-RTW.
Surgical reattachment of torn rotator cuff tendons can lead to satisfactory clinical outcome but failures remain common. Ortho-R product is a freeze-dried formulation of chitosan (CS) that is solubilized in platelet-rich plasma (PRP) to form injectable implants. The purpose of the current pilot study was to determine Ortho-R implant acute residency, test safety of different implant doses, and assess efficacy over standard of care in a sheep model. The infraspinatus tendon (ISP) was detached and immediately repaired in 22 skeletally mature ewes. Repair was done with four suture anchors in a suture bridge configuration (n = 6 controls). Freeze-dried formulations containing 1% w/v chitosan (number average molar mass 35 kDa and degree of deacetylation 83%) with 1% w/v trehalose (as lyoprotectant) and 42.2 mM calcium chloride (as clot activator) were solubilized with autologous leukocyte-rich PRP and injected at the tendon-bone interface and on top of the repaired site (n = 6 with a 1 mL dose and n = 6 with a 2 mL dose). Acute implant residency was assessed histologically at 1 day (n = 2 with a 1 mL dose and n = 2 with a 2 mL dose). Outcome measures included MRI assessment at baseline, 6 weeks and 12 weeks, histopathology at 12 weeks and clinical pathology. MRI images and histological slides were scored by 2 blinded readers (veterinarian and human radiologist, and veterinarian pathologist) and averaged. The Generalized Linear Model task (SAS Enterprise Guide 7.1 and SAS 9.4) was used to compare the different groups with post-hoc analysis to test for pairwise differences. Ortho-R implants were detected near the enthesis, near the top of the anchors holes and at the surface of ISP tendon and muscle at 1 day. Numerous polymorphonuclear cells were recruited to the implant in the case of ISP tendon and muscle. On MRI, all repair sites were hyperintense compared to normal tendon at 6 weeks and only 1 out 18 repair sites was isointense at 12 weeks. The tendon repair site gap seen on MRI, which is the length of the hyperintense region between the greater tuberosity and tendon with normal signal intensity, was decreased by treatment with the 2 mL dose when compared to control at 12 weeks (p = 0.01). Histologically, none of the repair sites were structurally normal. A trend of improved structural organization of the tendon (p = 0.06) and improved structural appearance of the enthesis (p = 0.1) with 2 mL dose treatment compared to control was seen at 12 weeks. There was no treatment-specific effect on all standard safety outcome measures, which suggests high safety. Ortho-R implants (2 mL dose) modulated the rotator cuff healing processes in this large animal model. The promising MRI and histological findings may translate into improved mechanical performance, which will be assessed in a future study with a larger number of animals. This study provides preliminary evidence on the safety and efficacy of Ortho-R implants in a large animal model that could potentially be translated to a clinical setting.
The purpose of this study was to validate a dry model for the assessment of performance of arthroscopic rotator cuff repair (RCR) and labral repair (LR). We hypothesised that the combination of a checklist and a previously validated global rating scale (GRS) would be a valid and reliable means of assessing RCR and LR when performed by residents in a dry model. An arthroscopic RCR and LR was performed on a dry model by residents, fellows, and sports medicine staff. Any prior RCR and LR exposure was noted. Participants were given a detailed surgical manuscript and technique video before the study began. Evaluation of residents was performed by staff surgeons with task-specific checklists created using a modified Delphi procedure, and the Arthroscopic Surgical Skill Evaluation Tool (ASSET). The hand movements and arthroscopic view of the procedures were recorded. Both videos were scored by a fellow blinded to the year of training of each participant. A total of 35 residents, six fellows and five staff surgeons performed both arthroscopic RCR and LR on a dry model model (48 total). The internal reliability (Cronbach's Alpha) of the test using the total ASSET score was high (>0.8)). One-way analysis of variance for the total ASSET score and the total checklist score demonstrated a difference between participants based upon year of training (p<0.05). Post hoc analysis also demonstrated a significant difference in global ratings and checklist scores between junior residents (PGY1–3) and senior residents (PGY4&5), senior residents and fellows, and fellows and staff. A good correlation was seen between the total ASSET score and prior exposure to RCR and LR. The inter-rater reliability (ICC) between the examiner ratings and the blinded assessor ratings for the total ASSET score was good (0.8). The results of this study provide evidence that the performance of a RCR and LR in a dry model is a valid and reliable method of assessing a resident's ability to perform these procedures, prior to performance in the operating room.
The optimal approach to arthroscopic repair of the rotator cuff is controversial, and both single row and double row fixation methods are commonly used. Which construct yields the highest efficacy is not clear. Given the current era of increasing costs in which health care delivery models are aiming for improved efficiencies and optimal outcomes, a cost-effectiveness study was performed to inform the decision making process of the utilisation of single versus double row repair. The purpose of this study was to evaluate the cost-effectiveness of single row versus double row constructs in patients undergoing arthroscopic rotator cuff repair. A cost-utility analysis was performed. Health resource use and outcome data were obtained from a previous prospective randomised controlled trial in which 90 patients were randomised to two treatment arms, single row rotator cuff repair (n=48) and double row (n=42). The patients were followed over a two-year span from the time of initial surgery. Unit cost data were captured using case costs collected from the hospital database and the Ontario Schedule of Benefits. Utility values were derived from published literature. The incremental cost effectiveness ratio (ICER), defined as the difference in cost between the two types of rotator cuff fixation divided by the difference in quality adjusted life years (QALY), was determined. Double row fixation was more costly ($2,279.94 versus $1,587.37) but was more effective than the single row method (QALY of 4.073 versus 4.055). An incremental cost-effectiveness ratio was estimated to be $38,504.92 per QALY for double row fixation relative to single row. This is well below the commonly used willingness to pay threshold of $50,000/QALY. Subgroup analysis demonstrated that patients with larger rotator cuff tears (>3cm) had a lower ICER, suggesting that double-row fixation may be more cost-effective in more severe tears. Double row rotator cuff fixation is a cost-effective option compared to single row rotator cuff repair with an ICER of $38,504.92/QALY, well within the accepted willingness to pay threshold of $50,000/QALY. Furthermore, the ICER between single and double row fixation improved with larger rotator cuff tears (>3cm), suggesting an additional benefit of a double row construct in those cases.
Given that there is limited time available to the surgeon in arthroscopic rotator cuff repair, how is the time best spent? Should they place one Modified Mason-Allen, two mattress or four simple sutures? This study reverses current thought. In an in-vitro biomechanical single pull to failure study we compared the ultimate tensile strength of simple, mattress and grasping sutures passed with an arthroscopic suture passer (Surgical Solutions Express-Sew). The aim was to determine which suture configurations would most simply, repeatably and reliably repair the rotator cuff. The ultimate tensile strength and mode of failure of six different suture configurations was repeatedly tested on a validated porcine rotator cuff tendon model, using a standard suture material (Number 2 Fiberwire) passed with the Surgical Solutions Express-sew, in a Hounsfield type H20K-W digital tensometer. Standardising the number of suture passes to four, the strongest construct was two mattress sutures (Mean 169N), followed by single Modified Kessler (Mean 161N), four simple sutures (Mean 155N) and finally a single Mason Allen suture (Mean 140N). Suture configurations involving two passes were all weaker than those with four (one way analysis of variance p=0.026), even when Number 2 Fibertape was used to augment strength. These results show little difference in strength for varying complexity of four pass suture passage (one way analysis of variance p=0.61). In simple terms there is no demonstrable difference in the strength of construct whether the surgeon uses four simple, two mattress or one grasping suture. This study allows the surgeon to justify using the simplest configuration of suture passage that works in his hands in order to obtain a reliable and repeatable repair of the rotator cuff arthroscopically.
To determine the benefit of dissolvable Balloon Arthroplasy in managing patients with massive irreparable rotator cuff tears (RCT). This is prospective pilot study carried out adhering to the local approval process. Patients having massive cuff tear with pain or functional limitation were seen by consultants and MRI confirmed the diagnosis. The patients were explained of ‘all available’ treatment options and information leaflet about the new procedure balloon arthroplasty, provided. Patients were seen after 4 weeks in a dedicated clinic to find out if they were willing to participate. Patients were seen by a physiotherapist pre and post-operatively at 6 weeks then at 3, 6 and 12months in addition to medical follow-ups, using VAS, Oxford Shoulder, Constant and SF36 scores. All procedures were carried out by consultant shoulder surgeons and where the cuff was reparable or contraindications identified were excluded.Aim
Methods
Review causes of anchor fixation failures in patients who underwent arthroscopic rotator cuff repair. Between 2003 and 2006, 650 arthroscopic rotator cuff repairs were performed by the senior author. Of these, anchor fixation failure occurred in fifteen patients. A retrospective review was undertaken to find out the reasons for their failure.Aim
Methods
Studies have shown that the trees minor plays an important role after total (TSA) and reverse (RSA) shoulder arthroplasty, as well as in maintenance of function in the setting of infraspinatus wasting. In this regard, teres minor hypertrophy has been described as a compensatory change in response to this infraspinatus wasting, and has been suggested that this compensatory hypertrophy may mitigate the loss of infraspinatus function in the patient with a large rotator cuff tear. The purpose of this study was to determine the prevalence of teres minor hypertrophy in a cohort of patients undergoing rotator cuff repair, and to determine its prognostic effect, if any, on outcomes after surgical repair. Over a 3 year period, all rotator cuff repairs performed in a single practice by 3 ASES member surgeons were collected. Inclusion criteria included both preoperative and postoperative validated outcomes measures (minimum 2 year), and preoperative Magnetic Resonance Imaging (MRI) scanning. 144 patients met all criteria. MRIs were evaluated for rotator cuff tear tendon involvement, tear size, and Goutallier changes of each muscle. In addition, occupational ratios were determined for the supraspinatus, infraspinatus, and teres minor muscles. Patients were divided into 2 groups, based upon whether they had teres minor hypertrophy or not, based on a previously established definition. A 2 way ANOVA was used to determine the effect of teres minor hypertrophy(tear size by hypertrophy) and Goutallier Teres minor hypertrophy was a relatively common finding in this cohort of rotator cuff patients, with 51% of all shoulders demonstrating hypertrophy. Interestingly, in patients without an infraspinatus tear, teres minor hypertrophy was still present in 19/40 (48%) of patients. Teres minor hypertrophy had a significant, negative effect ASES scores after rotator cuff repair in patients with and without infraspinatus tearing, infraspinatus atrophy, and fatty infiltrative changes (P<0.05). In general, the presence of teres minor hypertrophy showed 10–15% less improvement (Figure 1) than when no hypertrophy was present, and this was consistent across all tear sizes, independent of Goutallier changes. Teres minor hypertrophy is a common finding in the setting of rotator cuff tearing, including in the absence of infraspinatus tearing. Contrary to previous publications, the presence of teres minor hypertrophy in patients with rotator cuff repair does not appear to be protective as a compensatory mechanism. While further study is necessary to determine the mechanism or implication of teres minor hypertrophy in setting of rotator cuff repair, our results show it is not a positive of outcomes following rotator cuff repair.
Acute postoperative infection is reported to occur in 0.3–2% after arthroscopic rotator cuff repair. Few reports have addressed this dreaded complication although the costs are high both for the patient and for society. The aim of this prospective study was to describe incidence, treatment and outcome after acute postoperative infections following arthroscopic rotator cuff repair. Patients undergoing arthroscopic rotator cuff repair in our department have been prospectively registered since 2009. 11 out of 1072 patients undergoing surgery developed an acute postoperative infection. The patients were examined with an MRI scan and/or functional scores (Constant Murley (CM) and WORC) at final follow-up.Aim
Method
Glenoid version has been correlated with tears within the rotator cuff. Cuff tear arthropathy is an evolution of multiple unhealed tendons ultimately resulting in pseudoparalysis. Although several factors are critical to allow tendon healing, we have observed that there is less glenoid version in patients with cuff tear arthropathy. This was compared to those with osteoarthritis where rotator cuff tears are uncommon. We hypothesize that patients undergoing inverse prosthesis generally have a near neutral glenoid. A single surgeons practice (JPW) was retrospectively reviewed for all cuff tear arthropathy and osteoarthritis patients undergoing primary shoulder arthroplasty. (Zimmer, Warsaw, IN). Glenoid version was measured by 2 fellowship trained shoulder surgeons. Inter and intra-class correlation was measured.Purpose
Method
Arthroscopic rotator cuff repairs now yield a similar footprint as open procedures with several advantages, including reduced tissue trauma, post-operative pain, swelling, and concern about the deltoid attachment. We present a new simple and reproducible technique for arthroscopic rotator cuff repair. Sutures are placed through the full thickness of the rotator cuff. The suture is tied in the following manner: Traction is released, the assistant maintaining the arm in abduction and applying tension on the anterior cuff sutures while the posterior cuff sutures are tied. The procedure is repeated for the anterior cuff suture; and One suture strand from the anterior cuff and one suture strand from the posterior cuff are tied. The procedure is then repeated using the second strand from the anterior cuff and second suture strand from the posterior cuff. This suture and knot tying technique snugs the cuff down to the prepared tuberosity and restores the articular footprint of the cuff. This study retrospectively evaluated the clinical outcome of 170 patients who underwent arthroscopic cuff repair using this technique.Objective
Methods
One of the disadvantages of lateral decubitus position during arthroscopic rotator cuff repair is the difficulty to control arm rotation intraoperatively making it necessary to create additional portals for anchor placement or an additional scrubbed assistant to control arm rotation. We describe the use of commercially available TRIMANO® support arm from Arthrex as an easy device for secure positioning during arthroscopic rotator cuff repair in lateral decubitus position. Though initially marketed to be used for shoulder arthroplasties performed in beach chair position, the senior author has used TRIMANO® to perform arthroscopic rotator cuff repair in lateral decubitus position. The device is easily connected to the operating table side rail while the affected side forearm of the patient is placed in a disposable sterile foam arm holder and attached to the TRIMANO® arm. The “Click and Move” system of the TRIMANO® allows freedom to move the arm in any direction and also provides traction to distract the joint if needed.Introduction
Methods & Technique
Our aim was to accurately determine whether muscle atrophy and fatty infiltration are reversible following cuff repair. Patients with a repairable cuff-tear were recruited and assessed clinically and radiologically (Magnetic Resonance Imaging). At surgery, supraspinatus was biopsied. Post-operatively, patients underwent clinical evaluation at standardised intervals, with further MRI and an ultrasound guided biopsy of supraspinatus at 12 months. MRI was used to characterize cuff-tears and determine the degree of muscle atrophy and fatty infiltration. Biopsy samples were fixed on-site and transported for processing. Morphometric assessments of myofibres were made and mean cross-sectional areas calculated using validated techniques. The pathologist was blinded to sample details. Statistical analysis was performed to assess differences in mean myofibre area following cuff repair and correlated with radiological findings. Eight patients were available for completed histological and radiological analysis. Six (two re-tears) demonstrated sizeable and highly statistically significant improvements in mean myofibre cross-sectional area (P=0.000–0.0253). Of the two not showing any increase in myofibre area, neither result was statistically significant (P=0.06, 0.2); one was a re-tear and one was a repair of a partial-thickness tear. Radiologically, the muscle and fatty changes had not demonstrably changed. Our finding that myofibre cross-sectional area increases following cuff repair suggests muscle atrophy is a potentially reversible process. Even with re-tears, improvements were seen. MRI features of fatty infiltration and muscle atrophy were not seen to improve however. It is likely that radiological assessment is not sensitive enough to demonstrate the reversibility of muscle atrophy seen on histological analysis at one year.
Despite reverse total shoulder arthroplasty (RTSA) being primarily indicated for massive rotator cuff tears, it is often possible to repair portions of the infraspinatus and subscapularis of patients undergoing this procedure. However, there is disagreement regarding whether these tissues should be repaired, as their effects remain unclear. Therefore, we investigated the effects of rotator cuff repair and changes in humeral and glenosphere lateralisation (HLat & GLat) on deltoid and joint loading. Six shoulders were tested on an in-vitro muscle driven active motion simulator. Cuff tear arthropathy was simulated in each specimen, which was then implanted with a custom adjustable RTSA fitted with a six axis load sensor. We assessed the effects of 4 RTSA configurations (i.e. all combinations of 0&10mm of HLat & GLat) on deltoid force, joint load, and joint load angle during abduction with/out rotator cuff repair. Deltoid and joint loads recorded by the load cell are reported as a % of Body Weight (%BW). Repeated measures ANOVAs and pairwise comparisons were performed with p<0.05 indicating significance. Cuff repair interacted with HLat & GLat (p=0.005, Fig. 1) such that with no HLat, GLat increased deltoid force without cuff repair (8.1±2.1%BW, p=0.012) and this effect was significantly increased with cuff repair (12.8±3.2%BW, p=0.010). However, adding HLat mitigated this such that differences were not significant. HLat and GLat affected deltoid force regardless of cuff status (−2.5±0.7%BW, p=0.016 & +7.7±2.3%BW, p=0.016, respectively).
Background. The purpose of this retrospective study was to examine the functional outcomes of patients treated for isolated fracture of the greater tuberosity (GT) and to determine how their outcomes were affected by fracture pattern, treatment choices, associated shoulder injuries, the post fixation displacement of GT fragment and the time delay between injury and fixation. Methods. Forty-eight (28 male and 20 female) patients (mean age 45 years) treated at our institution between 1999–2009 matched our inclusion criteria. Thirty-five patients were treated surgically and 13 conservatively. Functional outcome was assessed using Oxford scores (OS), University of California and Los Angeles (UCLA) rating scale and the shoulder index of the American Shoulder and Elbow surgeons (ASES). The outpatient follow up time required and the presence of other shoulder injuries, time delay to surgery and the time off work were also recorded. Results. Outcome scores for patients who sustained simple vs comminuted fractures were not significantly different (OS = 41.8 vs 41, ASES 23.8 vs 23.4, UCLA 26.6 vs 26.3). Time taken off work was less in those who had a comminuted vs a simple fracture (21 vs 30 weeks). Shoulder dislocation was present in 77% and patients had a significantly worse outcome than those with no dislocation (OS = 40.6 vs 44, ASES 22.9 vs 26).
