Extracorporeal shock wave therapy is not useful after arthroscopic rotator cuff repair

Purpose

Extracorporeal shock wave therapy (ESWT) is known to accelerate the healing of musculoskeletal tissue. The purpose of this study was to test the hypothesis that ESWT stimulates rotator cuff healing after arthroscopic repair.

Methods

Seventy-one consecutive patients with a small- to large-sized rotator cuff tear underwent arthroscopic rotator cuff repair. The patients were randomized into two groups: 35 patients underwent ESWT at 6 weeks after surgery (ESWT group) and 36 patients did not (control group). Cuff integrity was evaluated with computed tomographic arthrography at 6 months after surgery. Constant and UCLA scores were measurable outcomes.

Results

All patients were available for a minimum one-year follow-up. The mean age of the ESWT and control groups was 59.4 (SD: 7.7) and 58.6 years (SD: 7.8) (n.s.). There were no significant differences in tear size and repair method between the two groups (n.s.). The mean Constant and UCLA scores, respectively, increased from 54.6 to 90.6 (P < 0.001) and from 18.5 to 27.4 (P < 0.001) in the ESWT group, and from 58.9 to 89.3 (P < 0.001) and 18.5 to 27.4 in the control group. Computed tomographic arthrography was performed in 26 patients from the ESWT group and 24 from the control group, and cuff integrity was maintained in 46 out of 50 patients. Definite re-tear was observed in two patients of the ESWT group and four of the controls. There were no complications associated with ESWT.

Conclusion

This study failed to prove that ESWT stimulates rotator cuff healing after arthroscopic rotator cuff repair. Additional ESWT after rotator cuff repair could theoretically be advantageous, and it was proven to be safe in this study.

Level of evidence

II.     

Analgesic effectiveness of nerve block in shoulder arthroscopy: comparison between interscalene, suprascapular and axillary nerve blocks

Purpose

Postoperative pain in arthroscopic shoulder surgery cannot be easily controlled with analgesics and nerve blocks. This study shows the analgesic effect of interscalene block (ISB) and suprascapular nerve block and axillary nerve block (SSNB + ANB) in patients under patient controlled analgesia (PCA).

Methods

Sixty-one patients (26 men and 35 women) who underwent arthroscopic rotator cuff repair were selected and allocated non-randomly to one of three groups: PCA only-group, PCA with ISB-group and PCA with SSNB + ANB-group. Visual analogue scale (VAS) score, degree of satisfaction, PCA usage and incidence of nausea and vomiting were evaluated at the recovery room, 8, 16 and 24 postoperative hours.

Results

The VAS score of the PCA only-group was highest at the recovery room. The VAS score of the PCA with ISB-group was the lowest, however, with large fluctuations over time. Although the VAS score of the PCA with SSNB + ANB-group was higher than that of the PCA with ISB-group, it was steadily lower than the PCA-only group, without any fluctuations. The degree of satisfaction of the PCA with ISB-group was highest at the recovery room. The number of times the PCA was used at the 8-h postoperative evaluation was largest in the PCA only-group.

Conclusions

The initial 24 h after surgery plays a key role in controlling pain after arthroscopic shoulder surgery. PCA with SSNB + ANB is a better anaesthetic choice than PCA with ISB or PCA only during the initial 24 h of the postoperative period.

Level of evidence

Clinical study, Level II.     

Preoperative and post-operative sleep quality evaluation in rotator cuff tear patients

Purpose

The aim of this study was to examine the potential relationship between subjective sleep quality and degree of pain in patients with rotator cuff repair.

Methods

Thirty-one patients who underwent rotator cuff repair prospectively completed the Pittsburgh Sleep Quality Index, the Western Ontario Rotator Cuff Index, and the Constant and Murley shoulder scores before surgery and at 6 months after surgery. Preoperative demographic, clinical, and radiologic parameters were also evaluated.

Results

The study analysed 31 patients with a median age of 61 years. There was a significant difference preoperatively versus post-operatively in terms of all PSQI global scores and subdivisions (p < 0.001). A statistically significant improvement was determined by the Western Ontario Rotator Cuff Scale and the Constant and Murley shoulder scores (p ? 0.001).

Conclusion

Sleep disorders are commonly seen in patients with rotator cuff tear, and after repair, there is an increase in the quality of sleep with a parallel improvement in shoulder functions. However, no statistically significant correlation was determined between arthroscopic procedures and the size of the tear and sleep quality. It is suggested that rotator cuff tear repair improves the quality of sleep and the quality of life.

Level of evidence

IV.

     

Preoperative NSAIDs,non-acute onset and long-standing symptoms predict inferior outcome at long-term follow-up after rotator cuff repair

Purpose

To evaluate mid- to long-term results after arthroscopic rotator cuff repair and to explore possible predictors of inferior outcome.

Methods

Patients treated for full-thickness supraspinatus and/or infraspinatus tears from 2004 to 2008, using a uniform single-row arthroscopic technique, were included in the study. Pre- and post-operative QuickDASH were used as the primary outcome measure, and VAS of pain, function and satisfaction were also collected. An additional questionnaire explored demographic and preoperative factors like onset and duration of symptoms, preoperative treatment and smoking habits.

Results

One hundred and forty-seven patients (82 %) were available at 6–9 years after surgery. All outcomes improved significantly from the preoperative values. A total of 8 % of patients had undergone additional surgery to the same shoulder during the follow-up period. Long-standing symptoms (>12 months) (P < 0.01), non-acute onset of symptoms (P < 0.01) and preoperative use of NSAIDs (P = 0.01) were correlated with inferior outcome at follow-up. No other factors investigated (i.e. gender, age, smoking and steroid injections) were found to affect the primary outcome (QuickDASH).

Conclusion

The current study is one of few reports of mid- to long-term outcomes after arthroscopic single-row repair of full-thickness rotator cuff tears. Global improvement in symptoms and function was found between the preoperative and the 6–9 years evaluation, and the technique therefore seems like a viable approach for treating tears of the supra- and the infraspinatus tendon. Several predictors of inferior long-term outcome after rotator cuff repair were, however, identified: preoperative use of NSAIDs, long-standing symptoms before surgery and non-acute onset of shoulder symptoms. In light of the current findings, accurate diagnosis and prompt treatment seem important in optimizing outcomes after rotator cuff surgery.

Level of evidence

IV.

     

Learning curve of office-based ultrasonography for rotator cuff tendons tears

Purpose

To compare the accuracy of ultrasonography and MR arthrography (MRA) imaging in detecting of rotator cuff tears with arthroscopic finding used as the reference standard.

Methods

The ultrasonography and MRA findings of 51 shoulders that underwent the arthroscopic surgery were prospectively analysed. Two orthopaedic doctors independently performed ultrasonography and interpreted the findings at the office. The tear size measured at ultrasonography and MRA was compared with the size measured at surgery using Pearson correlation coefficients (r). The sensitivity, specificity, accuracy, positive predictive value, negative predictive value and false-positive rate were calculated for a diagnosis of partial-and full-thickness rotator cuff tears. The kappa coefficient was calculated to verify the inter-observer agreement.

Results

The sensitivity of ultrasonography and MRA for detecting partial-thickness tears was 45.5 and 72.7 %, and that for full-thickness tears was 80.0 and 100 %, respectively. The accuracy of ultrasonograpy and MRA for detecting partial-thickness tears was 45.1 and 88.2 %, and that for full-thickness tears was 82.4 and 98 %, respectively. Tear size measured based on ultrasonography examination showed a poor correlation with the size measured at arthroscopic surgery (r = 0.21; p < 0.05). However, tear size estimated by MRA showed a strong correlation (r = 0.75; p < 0.05). The kappa coefficient was 0.47 between the two independent examiners.

Conclusions

The accuracy of office-based ultrasonography for beginner orthopaedic surgeons to detect full-thickness rotator cuff tears was comparable to that of MRA but was less accurate for detecting partial-thickness tears and torn size measurement. Inter-observer agreement on the interpretation was fair. These results highlight the importance of the correct technique and experience in operation of ultrasonography in shoulder joint.

Level of evidence

Diagnostic study, Level II.     

Expression of insulin-like growth factor type 1 receptor and myosin heavy chain in rabbit’s rotator cuff muscle after injection of adipose-derived stem cell

Purpose

This study was performed to evaluate the effects of adipose-derived mesenchymal stem cells (ADMSC) in a subacute rotator cuff tear model of a rabbit by way of comparing the expression of insulin-like growth factor 1 receptor (IGF-1R) and myosin heavy chain (MyHC) in the ADMSC injected muscle and control.

Methods

Supraspinatus tears were created in both shoulders of 11 rabbits, and rotator cuff repair was performed after 3 weeks. At the time of repair, each side of the shoulders was randomly selected, and the injection of the ADMSCs at the muscle belly near musculotendinous junction (injection side) and saline to the contralateral side (control side) was performed. After 3 weeks, we randomly assigned 5 rabbits to the immunohistochemistric analysis and 6 to Western blot analysis.

Results

Expression of both IGF-1R (95 kD) and MyHC (200 kD) at the injection side was significantly elevated compared to control side (both p = 0.028). Immunohistochemistry showed that staining areas of both IGF-1R and MyHC were overlapped with staining of ADMSCs.

Conclusion

The injection of ADMSCs resulted in high expression of IGF-1R and MyHC in subacute rotator cuff tear and repaired model in rabbit compared to control side. Therefore, the injected ADMSCs may assist in regeneration of the rotator cuff muscle by way of insulin-like growth factor 1 (IGF-1) signalling pathway. This result may suggest another solution to facilitate the recovery of rotator cuff muscle and to improve the result of rotator cuff repair by ADMSC injection via IGF-1 pathway, which is one of the potent anabolic pathways.     

Clinical outcomes after arthroscopic trans-tendon suture-bridge technique in partial-thickness articular-side rotator cuff tear

Purpose

We evaluated the functional and radiological outcomes of arthroscopic trans-tendon suture-bridge repair for partial-thickness articular-side rotator cuff tears.

Methods

From December 2008 to May 2010, 32 consecutive patients with partial-thickness articular-side rotator cuff tears prospectively underwent arthroscopic trans-tendon suture-bridge repair. We included patients with articular-side partial-thickness supraspinatus tears involving more than half the normal thickness. Patients underwent ultrasonography or magnetic resonance imaging postoperatively. The functional outcomes of patients were evaluated at a minimum 1 year postoperatively. The mean age and follow-up period for the patients were 51.8 ± 13.7 years and 17.4 ± 4.2 months, respectively. Five outcome measures were used before surgery and at the final follow-up: a visual analog scale (VAS) pain score, the American Shoulder and Elbow Surgeons (ASES) score, the Shoulder Rating Scale of the University of California at Los Angeles (UCLA), the Constant–Murley score and range of motion (ROM).

Results

The radiological follow-up rate was 87.5 %, and the follow-up rate for clinical evaluation was 96.9 %. Mean UCLA, ASES and Constant–Murley scores improved from 19.1 ± 5.4, 45.2 ± 16.0 and 58.0 ± 19.6 preoperatively to 35.7 ± 8.5, 79.0 ± 15.8 and 78.1 ± 12.9 at final follow-up, respectively (all p ≤ 0.001). Mean VAS score and ROM (forward flexion) improved from 6.1 ± 1.9 and 140 ± 36.6 preoperatively to 2.6 ± 1.9 and 163 ± 25.2 at the final follow-up, respectively (p ≤ 0.001). Additionally, the postoperative radiological examination showed cuff integrity without retear in all patients.

Conclusions

Arthroscopic trans-tendon suture-bridge repair for partial-thickness articular-side rotator cuff tears resulted in significant improvement in function compared with that before the operation.     

Effects of arthroscopy-guided suprascapular nerve block combined with ultrasound-guided interscalene brachial plexus block for arthroscopic rotator cuff repair: a randomized controlled trial

Purpose

The aim of this study was to compare the pain relieving effect of ultrasound-guided interscalene brachial plexus block (ISB) combined with arthroscopy-guided suprascapular nerve block (SSNB) with that of ultrasound-guided ISB alone within the first 48 h after arthroscopic rotator cuff repair.

Methods

Forty-eight patients with rotator cuff tears who had undergone arthroscopic rotator cuff repair were enrolled. The 24 patients in group 1 received ultrasound-guided ISB and arthroscopy-guided SSNB; the remaining 24 patients in group 2 underwent ultrasound-guided ISB alone. Visual analogue scale pain score and patient satisfaction score were checked at 1, 3, 6, 12, 18, 24, and 48 h post-operatively.

Results

Group 1 had a lower visual analogue scale pain score at 3, 6, 12, 18, 24, and 48 h post-operatively (1.7 < 2.6, 1.6 < 4.0, 3.5 < 5.8, 3.6 < 5.2, 3.2 < 4.2, 1.3 < 2.0), and a higher patient satisfaction score at 6, 12, 18, 24, and 36 h post-operatively than group 2 (7.8 > 6.0, 6.2 > 4.3, 6.4 > 5.1, 6.9 > 5.9, 7.9 > 7.1). Six patients in group 1 developed rebound pain twice, and the others in group 1 developed it once. All of the patients in group 2 had one rebound phenomenon each (p = 0.010). The mean timing of rebound pain in group 1 was later than that in group 2 (15.5 > 9.3 h, p < 0.001), and the mean size of rebound pain was smaller in group 1 than that in group 2 (2.5 > 4.0, p = 0.001).

Conclusion

Arthroscopy-guided SSNB combined with ultrasound-guided ISB resulted in lower visual analogue scale pain scores at 3–24 and 48 h post-operatively, and higher patient satisfaction scores at 6–36 h post-operatively with the attenuated rebound pain compared to scores in patients who received ultrasound-guided ISB alone after arthroscopic rotator cuff repair. The combined blocks may relieve post-operative pain more effectively than the single block within 48 h after arthroscopic cuff repair.

Level of evidence

Randomized controlled trial, Level I.ClinicalTrials.gov Identifier: NCT02424630.

     

Arthroscopic double-row repair of the rotator cuff: a comparison of bio-absorbable and non-resorbable anchors regarding osseous reaction

Purpose

The aim of this study was to analyse the osseous reaction after arthroscopic double-row rotator cuff repair using bio-absorbable poly-l-lactic acid (PLLA) and non-absorbable polyetheretherketone (PEEK) suture anchors. Focus of interest was the appearance of peri-implant fluid and anchor tunnel widening.

Methods

Thirty-six patients were evaluated at final follow-up (16 PLLA and 20 PEEK). Clinical results were acquired by use of the subjective shoulder value, the Constant score and the Western Ontario Rotator Cuff Index. Radiological results were analysed by supraspinatus tendon integrity, footprint coverage, muscular atrophy and fatty infiltration. Furthermore, anchor tunnel expansion was measured, anchor structure and peri-implant fluids graduated.

Results

At 28.4 ± 8.9-month follow-up, clinical outcome was similar (n.s.). MRI investigation revealed osseous reaction in both groups; tunnel widening was 0.9 ± 0.7 mm in PLLA and 0.8 ± 0.6 mm in PEEK anchors (n.s.). Peri-implant fluid was pronounced in PLLA anchors (p < 0.05). Tunnel widening was significantly higher in lateral anchors irrespectively of the material used. Tendon integrity, muscular atrophy, fatty infiltration and footprint coverage were not significantly different (n.s.).

Conclusion

Both materials lead to osseous reaction in this study, whereas consequences of pronounced fluid in PLLA patients remain unclear. Pronounced tunnel widening in lateral anchors leads to the assumption that other causes such as mechanical stress potentially have to be considered when analysing osseous reaction.

Level of evidence

III.     

Excellent healing rates and patient satisfaction after arthroscopic repair of medium to large rotator cuff tears with a single-row technique augmented with bone marrow vents

Purpose

This study evaluated the repair integrity and patient clinical outcomes following arthroscopic rotator cuff repair of medium to large rotator cuff tears using a single-row technique consisting of medially based, triple-loaded anchors augmented with bone marrow vents in the rotator cuff footprint lateral to the repair.

Methods

This is a retrospective study of 52 patients (53 shoulders) comprising 36 males and 16 females with a median age of 62 (range 44–82) with more than 24-month follow-up, tears between 2 and 4 cm in the anterior–posterior dimension and utilizing triple-loaded anchors. Mann–Whitney test compared Western Ontario Rotator Cuff (WORC) outcome scores between patients with healed and re-torn cuff repairs. Multivariate logistic regression analysed association of variables with healing status and WORC score. Cuff integrity was assessed on MRI, read by a musculoskeletal fellowship-trained radiologist.

Results

Magnetic resonance imaging (MRI) demonstrated an intact repair in 48 of 53 shoulders (91%). The overall median WORC score was 95.7 (range 27.6–100.0). A significant difference in WORC scores were seen between patients with healed repairs 96.7 (range 56.7–100.0) compared with a re-tear 64.6 (27.6–73.8), p < 0.00056.

Conclusions

Arthroscopic repair of medium to large rotator cuff tears using a triple-loaded single-row repair augmented with bone marrow vents resulted in a 91% healing rate by MRI and excellent patient reported clinical outcomes comparable to similar reported results in the literature.

Level of evidence

IV.

     

An arthroscopic pleated capsular shift for recurrent anterior dislocation of the shoulder

Purpose

This study examined the clinical results of an arthroscopic simple pleated capsular shift to treat severe recurrent anterior dislocation of the shoulder.

Methods

Twenty-four patients with anterior labroligamentous periosteal sleeve avulsion or advanced lesions who underwent an arthroscopic simple pleated capsular shift were included in this study. To create an arthroscopic simple pleated capsular shift, redundant capsules, including glenohumeral ligaments, were brought at least 1 cm lateral and 1 cm inferior and shifted to the prepared glenoid. Four sutures were made at the 5, 4, 3, and 1–2 o’clock positions with four anchors. Clinical results were evaluated using a visual analog scale (VAS), ROWE scores, active motion, and return to activity. Statistical analyses were carried out using paired t tests.

Results

Three out of 24 patients had complaints. Two patients with recurrent instability underwent a repeat surgery, while the other patient complained of a stiff shoulder. There was a significant improvement in the VAS and ROWE scores post-operatively versus pre-operatively (p < 0.001, p < 0.001, respectively), but no significant differences in active motion except for external rotation, which decreased post-operatively (p = 0.02).

Conclusions

In patients with severe recurrent anterior dislocation, simple pleated capsular shift provided a reliable result. Four capsular shift sutures, 1 cm lateral and 1 cm inferior from the glenoid, were sufficient to reduce shoulder joint volume and restore stability. The arthroscopic capsular shift could be an alternative method in the case of no available labral lesion for repair.

Level of evidence

Case series, Therapeutic, Level IV.     

Thickening of the inferior glenohumeral capsule: an ultrasound sign for shoulder capsular contracture

Objectives

The aim of this retrospective study was to measure the inferior glenohumeral capsule thickness of shoulders clinically affected by capsular contracture by comparison to the contralateral asymptomatic side.

Methods

Bilateral shoulder ultrasound (US) examinations of 20 patients with clinically or MRI proven unilateral capsular contracture were retrospectively assessed. Inferior capsule evaluation was performed with a transducer placed within the axilla in maximally abducted shoulders. Measurements were symmetrically performed orthogonally to the inferior glenohumeral ligament (IGHL) in the axial plane; the coronal plane was used to ensure the tension of the IGHL. The significance of any difference in thickening was assessed with the Mann–Whitney test.

Results

The average thickness was 4.0 mm in shoulders with capsular contracture vs. 1.3 mm in asymptomatic contralateral shoulders (P?<?0.0001). Twenty per cent of patients with capsular contracture and inferior capsule thickness increase showed US features of other painful diseases of the rotator cuff.

Conclusion

The thickness of the inferior capsule is measurable through ultrasound examination and appears to be increased in shoulders with capsular contracture. Exploration of the inferior aspect of the shoulder joint could be added to shoulder US examination protocols for capsular contracture assessment even if other rotator cuff abnormalities are diagnosed by US.

Key Points

? Ultrasound is increasingly used to diagnose shoulder problems. ? The thickness of the inferior glenohumeral ligament is measurable in the axilla. ? The inferior glenohumeral ligament appears thickened in shoulders with capsular contracture. ? Capsular contracture ultrasound features can be associated with other rotator cuff problems.     

Does adding heavy load eccentric training to rehabilitation of patients with unilateral subacromial impingement result in better outcome? A randomized, clinical trial

Purpose

To investigate superior value of adding heavy load eccentric training to conservative treatment in patients with subacromial impingement.

Methods

Sixty-one patients with subacromial impingement were included and randomly allocated to the traditional rotator cuff training (TT) group (n = 30, mean age = 39.4 ± 13.1 years) or traditional rotator training combined with heavy load eccentric training (TT + ET) group (n = 31, mean age = 40.2 ± 12.9 years). Isometric strength was measured to abduction at 0°, 45° and 90° of scapular abduction and to internal and external rotation. The SPADI questionnaire was used to measure shoulder pain and function. Patients rated subjective perception of improvement. Outcome was assessed at baseline, at 6 and 12 weeks after start of the intervention. Both groups received 9 physiotherapy treatments over 12 weeks. At home, the TT group performed traditional rotator cuff strengthening exercises 1x/day. The TT + ET group performed the same exercises 1x/day and a heavy load eccentric exercise 2x/day.

Results

After treatment, isometric strength had significantly increased in all directions, and SPADI score had significantly decreased. The TT + ET group showed a 15 % higher gain in abduction strength at 90° of scapular abduction. Chi-square tests showed patients’ self-rated perception of improvement was similar in both groups.

Conclusion

Adding heavy load eccentric training resulted in a higher gain in isometric strength at 90° of scapular abduction, but was not superior for decreasing pain and improving shoulder function. This study showed that the combination of a limited amount of physiotherapy sessions combined with a daily home exercise programme is highly effective in patients with impingement.

Level of evidence

II.     

Identifiable risk factors for thirty-day complications following arthroscopic rotator cuff repair

Objectives: Shoulder arthroscopy has increased in frequency over the past decade, with rotator cuff repair comprising the majority of cases performed. Prior studies have detailed risk factors for 30-day complications and readmission rates after arthroscopic shoulder surgery using the National Surgical Quality Improvement Program (NSQIP) database, but no study has specifically looked at arthroscopic rotator cuff repair. The purpose of the study is to evaluate the risk factors for 30-day complications following arthroscopic rotator cuff repair using the NSQIP database.

Methods: The NSQIP database was queried for all patients undergoing arthroscopic rotator cuff repair from 2006–2015. Demographics and thirty-day outcomes for these patients were analyzed using univariate analyses and multivariate regression analysis to determine the risk factors for complications.

Results: 21,143 patients underwent arthroscopic rotator cuff repair, with 147 patients (0.70%) having a complication within 30-days. Univariate analysis found age >65 (p = 0.0028), male gender (p = 0.0053), elevated BMI (p = 0.0054), ASA class >2 (p < 0.0001), history of chronic obstructive pulmonary disease (p < 0.0001), hypertension (p < 0.0002), dyspnea (p < 0.0001), steroid use (p = 0.0350), and operative time >90 min (p = 0.0316) to be associated with increased risk of complications. Multivariate analysis found female sex to be protective or complication (OR 0.56, p = 0.0017), while American Society of Anesthesiology (ASA) class >2 (OR 1.51, p = 0.0335) and history of COPD (OR 2.41, p = 0.0030) and dyspnea (OR 1.89, p = 0.0359) to be risk factors for complication. The most common complication is venothromboembolic events, accounting for 36.7% of all complications.

Conclusion: Male sex, ASA class > 2, and history of COPD and dyspnea were independent risk factors for thirty-day complications following arthroscopic rotator cuff repair.

Level of evidence: IV     

The science of rotator cuff tears: translating animal models to clinical recommendations using simulation analysis

Purpose

The purpose of this article is to review basic science studies using various animal models for rotator cuff research and to describe structural, biomechanical, and functional changes to muscle following rotator cuff tears. The use of computational simulations to translate the findings from animal models to human scale is further detailed.

Methods

A comprehensive review was performed of the basic science literature describing the use of animal models and simulation analysis to examine muscle function following rotator cuff injury and repair in the ageing population.

Results

The findings from various studies of rotator cuff pathology emphasize the importance of preventing permanent muscular changes with detrimental results. In vivo muscle function, electromyography, and passive muscle–tendon unit properties were studied before and after supraspinatus tenotomy in a rodent rotator cuff injury model (acute vs chronic). Then, a series of simulation experiments were conducted using a validated computational human musculoskeletal shoulder model to assess both passive and active tension of rotator cuff repairs based on surgical positioning.

Conclusion

Outcomes of rotator cuff repair may be improved by earlier surgical intervention, with lower surgical repair tensions and fewer electromyographic neuromuscular changes. An integrated approach of animal experiments, computer simulation analyses, and clinical studies may allow us to gain a fundamental understanding of the underlying pathology and interpret the results for clinical translation.     

The effects of Low-intensity Pulsed Ultrasound on tendon-bone healing in a transosseous-equivalent sheep rotator cuff model

Purpose

The purpose of this study was to examine the effects Low-intensity Pulsed Ultrasound has on initial tendon-bone healing in a clinically relevant extra-articular transosseous-equivalent ovine rotator cuff model.

Methods

Eight skeletally mature wethers, randomly allocated to either control group (n = 4) or treatment group (n = 4), underwent rotator cuff surgery following injury to the infraspinatus tendon. All animals were killed 28 days post surgery to allow examination of early effects of Low-intensity Pulsed Ultrasound treatment.

Results

General improvement in histological appearance of tendon-bone integration was noted in the treatment group. Newly formed woven bone with increased osteoblast activity along the bone surface was evident. A continuum was observed between the tendon and bone in an interdigitated fashion with Sharpey’s fibres noted in the treatment group. Low-intensity Pulsed Ultrasound treatment also increased bone mineral density at the tendon-bone interface (p < 0.01), while immunohistochemistry results revealed an increase in the protein expression patterns of VEGF (p = 0.038), RUNX2 (p = 0.02) and Smad4 (p = 0.05).

Conclusions

The results of this study indicate that Low-intensity Pulsed Ultrasound may aid in the initial phase of tendon-bone healing process in patients who have undergone rotator cuff repair. This treatment may also be beneficial following other types of reconstructive surgeries involving the tendon-bone interface.     

Superiority of bridging techniques with medial fixation on initial strength

Purpose

The purpose of our study was to evaluate the initial fixation strength of bridging techniques compared to other suture techniques for rotator cuff repair using a biomechanical animal model, which incorporated pretesting of intact tendons.

Methods

Seventy-six fresh bovine shoulders were used for testing seven suture configurations including simple suture (SS), mattress suture (MS), Mason-Allen (MA), modified double row (mDR), SpeedBridge (SpB), SpeedBridge with medial fixation (mSpB), and double-mattress SutureBridge (dmSuB) techniques. Cyclic loading was performed with all intact bone-tendon complex before (pretest) and after repair of the tendon (main test) at the level of 10 and 180 N at 100 Hz with displacement-controlled ramps of ±33 mm/s. The pretest was stopped after 200 cycles. For the main test, the loading scheme was continued for a maximum of 500 cycles or until failure.

Results

The mean elongation of all 76 intact tendons measured at the pretest was 3.8 ± 0.6 mm (2.4–5.4 mm). No differences of gap formations at the 1st cycle were detected between SS, MS, MA, and mDR. SpB showed significant higher gap formations compared to all other suture techniques (p = 0.001). No significant differences were detected between mSpB and dmSuB, whereas both techniques were significant different when compared to the other groups (p < 0.05).

Conclusions

In this study, results showed that bridging techniques with medial fixations have superior initial repair strength compared to other suture techniques. Knowledge of initial fixation strength of rotator cuff repair techniques may be of informative value to the surgeon.     

Eccentric versus conventional exercise therapy in patients with rotator cuff tendinopathy: a randomized,single blinded,clinical trial

Purpose

To investigate the effectiveness of isolated eccentric versus conventional exercise therapy in patients with rotator cuff tendinopathy.

Methods

Thirty-six patients with rotator cuff tendinopathy, diagnosed by an orthopaedic surgeon, were included and randomly allocated to an isolated eccentric exercise (EE) group (n = 20, mean age = 50.2 ± 10.8 years) or a conventional exercise (CG) group (n = 16, mean age = 48.6 ± 12.3 years). Both groups fulfilled a 12-week daily home-based exercise programme and received a total amount of nine treatment sessions. The Constant Murley score was used to evaluate both objective (e.g. range of motion and strength) and subjective measures (e.g. pain and activities of daily living). A visual analogue scale (VAS) was used to evaluate pain during daily activities. As secondary outcomes, shoulder range of motion and isometric abduction strength in 45° in the scapular plane were evaluated. All measurements were taken at baseline, at 6, 12 and 26 weeks.

Results

After 26 weeks, both groups showed a significant increase in the Constant Murley score and a significant decrease in VAS scores. No difference was found between the groups, for any of the evaluated outcome measures.

Conclusion

A 12-week-isolated eccentric training programme of the rotator cuff is beneficial for shoulder function and pain after 26 weeks in patients with rotator cuff tendinopathy. However, it is no more beneficial than a conventional exercise programme for the rotator cuff and scapular muscles. Based on the results, clinicians should take into account that performing two eccentric exercises twice a day is as effective as performing six concentric/eccentric exercises once a day in patients with rotator cuff tendinopathy.

     

Acromial morphology in patients with calcific tendinitis of the shoulder

Purpose

The purpose of this study was to evaluate whether the morphology of the acromion in calcific tendinitis differs from controls without subacromial pathology and matches subacromial impingement.

Methods

Digital radiographs of 150 shoulders were evaluated with the open source DICOM-Viewer OsiriX. 50 patients had symptomatic calcific tendinitis of the shoulder, 50 had subacromial impingement without calcifications or rotator cuff tears, 50 with bruised shoulder that were previously asymptomatic served as controls. Acromial shape according to Bigliani et al. acromial tilt (AT) according to Kitay et al. and Aoki et al. acromion index (AI) according to Nyffeler et al. and lateral acromial angle (LAA) according to Banas et al. were measured.

Results

Both calcific (0.72; P = 0.001) and impingement groups (0.73; P = 0.008) were significantly different from controls (0.67) using AI measure, while only the calcific group (79.5°) was different from controls (84.1°) using LAA (P < 0.001), and only the impingement group (32.9°) was different from controls (29.2°) using AT (P < 0.001). An LAA <70° only occurred in two patients with calcific tendinitis.

Conclusion

The hypothesis of this study was that the morphology of the acromion in calcific tendinitis differs from controls without subacromial pathology and matches subacromial impingement was only confirmed for the AI. The AI of shoulders with calcific tendinitis is comparable to that of shoulders with subacromial impingement.

Level of evidence

IV.