Malvidin attenuates trauma-induced heterotopic ossification of tendon in rats by targeting Rheb for degradation via the ubiquitin-proteasome pathway.

The pathogenesis of trauma-induced heterotopic ossification (HO) in the tendon remains unclear, posing a challenging hurdle in treatment. Recognizing inflammation as the root cause of HO, anti-inflammatory agents hold promise for its management. Malvidin (MA), possessing anti-inflammatory properties, emerges as a potential agent to impede HO progression. This study aimed to investigate the effect of MA in treating trauma-induced HO and unravel its underlying mechanisms. Herein, the effectiveness of MA in preventing HO formation was assessed through local injection in a rat model. The potential mechanism underlying MA's treatment was investigated in the tendon-resident progenitor cells of tendon-derived stem cells (TDSCs), exploring its pathway in HO formation. The findings demonstrated that MA effectively hindered the osteogenic differentiation of TDSCs by inhibiting the mTORC1 signalling pathway, consequently impeding the progression of trauma-induced HO of Achilles tendon in rats. Specifically, MA facilitated the degradation of Rheb through the K48-linked ubiquitination-proteasome pathway by modulating USP4 and intercepted the interaction between Rheb and the mTORC1 complex, thus inhibiting the mTORC1 signalling pathway. Hence, MA presents itself as a promising candidate for treating trauma-induced HO in the Achilles tendon, acting by targeting Rheb for degradation through the ubiquitin-proteasome pathway.

Hyperlipidemia in tendon injury: chronicles of low-density lipoproteins.

Hyperlipidemia impacts millions of people globally and has been the major risk factor for developing atherosclerosis and cardiovascular disease. Interestingly, hyperlipidemic subjects exhibit increased incidence of rotator cuff tendon injury (RCTI) and disorganization of tendon matrix. Low-density lipoproteins (LDL) and its oxidized form (ox-LDL) play a crucial role in hyperlipidemia-driven pro-inflammatory responses in multiple tissues including the tendon. The signaling of oxLDL upregulates the inflammatory cytokines, chemokines, adhesion molecules, and the activation of monocytes/macrophages/resident tendon cells and matrix metalloproteinases impairing the tendon homeostasis resulting in the alteration of extracellular matrix. In addition, the hyperlipidemia-driven immune response and subsequent oxidative stress promote degenerative responses in the tendon tissue. However, the pathological mechanisms underlying the occurrence of RCTI in hyperlipidemia and the effect of ox-LDL in tendon matrix are currently unknown. The present review focuses on the implications and perspectives of LDL/oxLDL on the increased incidence of RCTI.

Association of incidence rate of spontaneous tendon rupture and renal bone disease in end-stage renal disease patients' cohort.

INTRODUCTION: Spontaneous tendon rupture (STR) is one of the complications related to hyperparathyroidism. This study aims to verify this and to elucidate the feasibility of combined incidence rate of STR and bony fracture to assess clinical management of renal bone disease in dialysis cohort. METHOD: This is a clinical audit of cases of STR and fracture with 5504 patient-year dialysis vintage over 10 years. In order to verify the risk factor, comparison of cases of tendon rupture, the gender, and dialysis vintage matched patients without tendon rupture were done, followed by comparison with post-parathyroidectomy patients. RESULT: Six cases of STR involving eight tendons were identified, including a case of concurrent tendon rupture and bony fracture. These include two cases of double tendons ruptures. During this time, there were 15 cases of bony fracture without tendon rupture. The overall incidence rate for STR and fracture was of 0.0011 and 0.0029 incidence per year of dialysis vintage or one case per 917 and 344 patient-year dialysis vintage, respectively. For patients with PTH ≥ 600 pg/mL, the incidence rate of tendon rupture and fracture was 0.0199 and 0.0430 incidence per person-years or one case per 50 and 23 person-years, respectively. For patients with PTH < 600 pg/mL, the respective rate was 0 and 0.0006 incidence per person-years or one case per >5202 and 1734 person-years. There was significant difference for incidence rates of tendon rupture and fracture between these two groups, with six incidences of tendon rupture per 302 patient-dialysis-years of PTH ≥ 600 pg/mL versus 0 incidence per 5202 patient-year dialysis vintage of PTH < 600 pg/mL (p < 0.001). In similar comparison, there was also significant difference for incidence rate of fracture with 13/302 versus 2/5202 (p < 0.001). In the 5 yearly audit over 10 years, the incidence rates of tendon rupture and fracture have dropped from 0.0052 to 0.0028 or one incidence per 192 to 356 person-years. Among 35 patients post-parathyroidectomy, there was an incidence of tendon rupture in a patient with recurrence of hyperparathyroidism, 5 years after surgery. Comparing six survived patients with tendon rupture versus 12 age-gender-dialysis vintage matched patients, hyperparathyroidism has been shown to be most important risk factor. And subsequently, comparing them with six post-parathyroidectomy patients, reduction of alkaline phosphatase (ALP) has been shown to be associated with lower risk of tendon rupture. Median survival in patients with history of tendon rupture and those with history of fracture was 5.9 and 2.2 years, respectively (p = 0.192). CONCLUSION: Although rare, end-stage renal failure patients on dialysis with PTH > 600 pg/mL had high risk of tendon rupture and bony fracture. Parathyroidectomy might reduce the risk of tendon rupture and fracture with lowering ALP signifying reduction in bone turn over. Combined incidence rate of tendon rupture and fracture could be used to assess the control of hyperparathyroidism related issues in dialysis center.

Higher Soong grade predicts flexor tendon issues after volar plating of distal radius fractures - a retrospective cohort study.

BACKGROUND AND PURPOSE: Soong classification is used to estimate volar locking plate prominence and evaluate the risk for flexor tendon ruptures after surgical treatment of distal radius fractures (DRFs). However, the scientific community has questioned the Soong classification due to lacking evidence. Therefore, this study aimed to evaluate the accuracy of Soong grading as a predictor for flexor tendon issues and plate removal. PATIENTS AND METHODS: We performed a retrospective single-center review of adult distal radius fracture patients treated with a volar locking plate between 2009 and 2019. In total, 2779 patients were included in the study. The primary outcome was a flexor tendon issue (flexor tendon rupture, tendinitis, or flexor irritation), whereas plate removal was a secondary outcome. Using Soong grade 0 as a reference, we used univariable and multivariable logistic regression to calculate odds ratios (OR) with 95% confidence intervals (CI) for flexor tendon issues and plate removal. RESULTS: In total, 756 (27%) patients were graded as Soong 0, 1679 (60%) Soong 1, and 344 (12%) Soong 2, respectively. There were 32 (1.2%) patients with flexor tendon issues, of which 4 were flexor tendon ruptures, 8 tendinitises, and 20 flexor irritations. The adjusted OR for flexor tendon issues was 4.4 (CI 1.1-39.7) for Soong grade 1 and 9.7 (CI 2.2-91.1) for Soong grade 2. The plate was removed from 167 (6.0%) patients. Soong grade 1 had a univariable OR of 1.8 (CI 1.2-2.8) for plate removal, and Soong grade 2 had an OR of 3.5. (CI 2.1-5.8), respectively. CONCLUSION: Flexor tendon ruptures are rare complications after the volar plating of DRFs. A higher Soong grade is a risk factor for flexor tendon issues and plate removal. TRIAL REGISTRATION: The trial was retrospectively registered.

Poorer functional Outcomes in Patients with Multi-Ligamentous Knee Injury with Concomitant Patellar Tendon Ruptures at 5 years Follow-Up.

PURPOSE: Multi-ligamentous knee injuries (MLKIs) are high-energy injuries that may infrequently present with concomitant patellar tendon rupture. There is limited information in the literature regarding these rare presentations, with even less information regarding clinical outcomes. Using propensity-score matching, the purpose of this study was to compare the outcomes of MLKIs with and without patellar tendon ruptures and to investigate the overall predictors of these outcomes. METHODS: Twelve patients who underwent surgical repair for combined MLKI and patellar tendon rupture from 2011 to 2020 with minimum 1-year follow-up data were identified from two separate institutions. Patients were propensity-score matched with a 1:1 ratio with controls based on age, body mass index (BMI), gender, and time from surgery. Patient-reported outcomes included International Knee Documentation Committee (IKDC) Subjective Knee Form, Lysholm and Tegner scores. RESULTS: Twelve MLKIs with concomitant patellar tendon injuries were identified out of a multicenter cohort of 237 (5%) patients sustaining MLKI and were case matched 1:1 with 12 MLKIs without extensor mechanism injuries. The average follow-up was 5.5 ± 2.6 years. There were no differences in Schenck Classification injury patterns. There were significant differences found across IKDC (Patellar Tendon mean: 53.1 ± 24.3, MLKI mean 79.3 ± 19.6, P < 0.001) and Lysholm scores (Patellar Tendon mean: 63.6 ± 22.3, MLKI mean 86.3 ± 10.7, P < 0.001) between the two, illustrating poorer outcomes for patients with concomitant patellar tendon ruptures. CONCLUSION: In the setting of MLKI, patients who have a concomitant patellar tendon rupture have worse functional outcomes compared to those without. This information will be important for patient counseling and might be considered to be added to Schenck classification, reflecting its prognostic value. LEVEL OF EVIDENCE: Level IV.

Trends and complications of distal biceps tendon repair among American Board of Orthopaedic Surgery part II oral examination candidates.

BACKGROUND: Surgical fixation of distal biceps tendon ruptures can restore supination strength and minimize biceps fatigue, resulting in high patient satisfaction rates. Surgical approaches can vary (single incision vs. double incision), and the number of fixation techniques has increased in recent years. The reported rate of postoperative complications after surgical repair of distal biceps tendon injuries is high, ranging from 15% to 35%. The purpose of this study was to assess the trends and postoperative complication profile among newly trained surgeons who performed distal biceps tendon repairs utilizing the American Board of Orthopaedic Surgery database. METHODS: The American Board of Orthopaedic Surgery database was retrospectively queried for patients treated with distal biceps tendon repair by part II examination candidates between 2017 and 2020. Distal biceps tendon repairs were isolated using the Current Procedural Terminology code 24,342. Distal triceps tendon injuries were excluded with International Classification of Diseases code S46.3∗∗. Patient demographics, intraoperative data, and surgeon fellowship training were collected. Surgeon-reported postoperative 90-day complications, including general anesthetic, medical, and surgical complications, rates of readmission, and rates of reoperation were recorded. Comparisons of rates among patient groups organized by surgeon fellowship training were performed using the chi-squared test. RESULTS: A total of 2089 distal biceps tendon repairs were included in the analysis. The average patient age was 47.5 yr, and 97.3% of patients were men. The majority of cases was performed by surgeons with fellowship training in sports medicine, hand/upper extremity, and shoulder and elbow, with 867 (41.5%) cases performed by sports medicine-trained surgeons, 740 (35.4%) by hand/upper extremity-trained surgeons, and 313 (15.0%) by shoulder and elbow-trained surgeons. In total, 608 (29.1%) patients experienced an anesthetic (0.2%), medical (1.1%), or surgical (28.2%) complication. The most common surgical complications were nerve injury (20.6%), failure of tendon repair or fixation (2.4%), and infection (1.7%). The overall reoperation rate was 2.4%. There were no significant differences in complication or reoperation rates among subspecialty training received. DISCUSSION AND CONCLUSION: Among newly trained surgeons, those with fellowship training in sports medicine, hand/upper extremity, and shoulder and elbow performed the most distal biceps tendon repairs, and there was no difference in complication rates among subspecialty training received. Complication rates after distal biceps tendon repair performed by newly trained surgeons were similar to those previously reported in large cohort studies, with nerve injury as the most common complication.

Risk Factors for Contralateral Tendon Rupture in Patients With Acute Achilles Tendon Rupture.

The present study was performed to determine the incidence and risk factors of contralateral Achilles tendon rupture after an initial tendon rupture, and to identify the associated patient characteristics. Medical records of 181 adult patients with acute Achilles tendon rupture were reviewed. We investigated the risk factors for contralateral Achilles tendon rupture and calculated the incidence density (per 100 person-years), survival rate, hazard ratios, and 95% confidence intervals. The risk factors were extracted, including blood type, age, body mass index (BMI), occupation, underlying comorbidities, history of alcohol intake or smoking, injury mechanism, and fluoroquinolone antibiotic or steroid use. Military personnel and manual laborers, including farmers and firefighters were considered to have an occupation involving physical activity. Ten patients (5.5%) were identified as having nonsimultaneous, contralateral Achilles tendon rupture a mean of 3.3 years (range 1.0-8.3 years) after the initial tendon rupture. The incidence density of contralateral tendon rupture was 0.89 per 100 person-years. The 8-year survival rate of contralateral tendon rupture was 92.2%. Unadjusted and adjusted hazard ratios (with 95% confidence intervals, p value) of blood type O were 3.71 (1.07-12.82, p = .038) and 2.90 (0.81-10.32, p = .101), respectively, and those of occupations involving physical activity were 5.87 (1.64-20.98, p = .006) and 4.69 (1.27-17.28, p = .02), respectively. Based on the present data, blood type O and occupations involving physical activity are significantly associated with an increased risk of contralateral tendon rupture in adult patients who have sustained Achilles tendon rupture.

A Neglected Extensor Hallucis Longus Tendon Rupture Caused by Arthritic Adhesion.

Extensor hallucis longus tendon injury is relatively rare and is principally caused by a laceration when a sharp object is dropped on the instep. Primary suturing is possible if the injury is acute, but if the tear is chronic, tendon contracture causes the space between the edges of the tear to widen, disrupting the end-to-end connection. In particular, a claw toe or checkrein foot deformity may develop over time due to adhesion of the lower leg tendons near the fracture site or scar. We report on a 44-year-old man who visited our outpatient clinic complaining of pain in the right foot and a hindered ability to extend his great toe. He had enjoyed playing soccer during his schooldays; since that time, the extension of that toe had become somewhat difficult. T2-weighted sagittal magnetic resonance imaging revealed that the continuity of the extensor hallucis longus tendon had been lost at the distal phalangeal base attachment site, and that the region of the proximal tendon was retracted to level of the middle shaft of the proximal phalanx. The findings allowed us to diagnose extensor hallucis longus tendon rupture accompanying osteoarthritic changes in the joint and soft tissues. We performed surgical tenorrhaphy and adhesiolysis. This is a rare case of extensor hallucis longus tendon rupture caused by minor trauma. Arthritis that developed at a young age caused the adhesions. If patients with foot and ankle arthritis show tendon adhesion at the arthritic site, tendon rupture can develop even after minor trauma or intense stretching.

Spontaneous tendon rupture in a patient with systemic sclerosis: a case report.

BACKGROUND: Systemic sclerosis (SSc) is an incurable autoimmune disease characterized by progressive skin fibrosis and organ failure. Tenosynovitis is a common musculoskeletal manifestation, but tendon rupture has seldom reported in SSc. CASE PRESENTATION: We present a rare case of a 49-year-old female with SSc who has suffered from bilateral tendon rupture of the fourth and fifth digits with positive antinuclear antibody (ANA) and anti-centromere B antibody, but negative rheumatoid factor in serum. In the extensor tendons of the patient's hands, inflammation, edema, hypertrophy and tendon interruption were detected with ultrasound and magnetic resonance imaging(MRI). Tendon transfer repair surgery was performed and 10 mg/week methotrexate was then used in this patient. Her hand function was improved well with methotrexate and rehabilitation treatment postoperatively. CONCLUSIONS: Early detection of tenosynovitis is necessary to prevent tendon rupture in SSc patients. Ultrasound and Magnetic Resonance Imaging appear to be useful examinations for evaluating tendon pathology for early detection.

Review of human supraspinatus tendon mechanics. Part I: fatigue damage accumulation and failure.

Repetitive stress injuries to the rotator cuff, and particularly the supraspinatus tendon (SST), are highly prevalent and debilitating. These injuries typically occur through the application of cyclic load below the threshold necessary to cause acute tears, leading to accumulation of incremental damage that exceeds the body's ability to heal, resulting in decreased mechanical strength and increased risk of frank rupture at lower loads. Consistent progression of fatigue damage across multiple model systems suggests a generalized tendon response to overuse. This finding may allow for interventions before gross injury of the SST occurs. Further research into the human SST response to fatigue loading is necessary to characterize the fatigue life of the tendon, which will help determine the frequency, duration, and magnitude of load spectra the SST may experience before injury. Future studies may allow in vivo SST strain analysis during specific activities, generation of a human SST stress-cycle curve, and characterization of damage and repair related to repetitive tasks.

Systematic review of distal biceps tendon rupture in athletes: treatment and rehabilitation.

BACKGROUND: Distal biceps tendon rupture is a rare injury associated with decreased elbow flexion and forearm supination strength. This impairment is not tolerated by high-demand patients like athletes. PURPOSE: To review treatment and rehabilitation applied to injured athletes and study their impact in return to sports. METHODS: MEDLINE, Cochrane, Web of Science, and Scopus online databases were searched. A systematic review was conducted using the PRISMA guidelines; studies published on distal biceps tendon rupture treatment and rehabilitation of athletes until June 30, 2021, were identified. A quantitative synthesis of factor related to return to preinjury sport activity was made. RESULTS: Ten articles were identified, including 157 athletes. Mean age was 40.5 years, and the dominant arm was injured in 103 cases (66%). Rupture was acute in 121 athletes (77%), and the mean follow-up was 25.7 months. A hundred and fifty-three athletes (97.5%) successfully returned to sport within a mean time of 6.2 months. Surgical treatment was followed in all cases. One-incision technique was chosen in 115 (73%) and suture anchor fixation in 52 (33%) cases. No postsurgical immobilization was reported in 38 (24%) and immobilization for 2 weeks in 124 (79%) athletes. Decreased supination-pronation and flexion-extension arc was found in 63 (40%) and 27 (17%) cases, respectively. Earlier return to sport was associated with nondominant-side (P = .007) and acute (P < .001) injuries, participation in weightlifting (P = .001), double-incision approach (P = .005), cortical button fixation (P < .001), and absence of supination-pronation restriction (P = .032). Time of return to sport activity was independent of rehabilitation, including immobilization (P = .539) and strengthening (P = .155), and decreased flexion-extension arc (P = .059). CONCLUSION: Athletes sustaining distal biceps tendon rupture have a high postoperative return to sport rate, independently of selected surgical technique or rehabilitation program. However, a relation between the surgical technique and time of return to sport was found. Rehabilitation did not influence time of return to sport.

Chronic Rupture of Achilles Tendon Caused by Haglund's Deformity: A Case Report.

A chronic Achilles tendon rupture is a tendon rupture occurring more than 4-6 weeks after a traumatic injury. Haglund's deformity, caused by bony abnormalities in the ankle (mostly due to osteophyte or bone spur), can cause chronic inflammation and degeneration of the Achilles tendon, eventually leading to rupture. This presents a challenge for clinicians who provide tendon repair procedures. We present a 69-year-old woman who had difficulty moving her left leg and had a deformity on the left leg compared to her right leg after falling nine months before but with pain starting three months before the accident. There was a seven-centimeter gap in the calcaneus with a positive Thompson test. The Haglund's deformity on the left calcaneus was visible on the ankle X-ray. The patient had a chronic total rupture of the left Achilles tendon, which was treated with a flexor hallucis longus (FHL) tendon transfer and resection of the deformity. One week after surgery, the patient's ability to walk and the shape of the left leg improved. This case report describes a chronic left Achilles tendon condition that was successfully repaired through tendon repair surgery using FHL tendon transfer and removal of Haglund's deformity.

Proximal sciatic neuropathy secondary to hamstring tendon avulsion.

We herein present the exceptional case of a patient, who injured a sciatic nerve due to avulsion of proximal hamstring tendon in a motorcycle accident. The 63-year-old man was diagnosed firstly with an incomplete fracture of distal femur. A foot drop on the right side was observed when the full-length cast was removed two months later. The patient was referred to the neurology clinic and was diagnosed with a sciatic nerve lesion at the proximal level of the biceps femoris. Magnetic resonance imaging of the thigh showed a proximal avulsion of hamstring muscles tendon. The patient did not improve by short-term physiotherapy and neurosurgical intervention. Sciatic nerve injury can be a result of proximal hamstring avulsion in events such as motorcycle accidents even in the absence of complete or major femur fracture.

Fibular Tip Periostitis: New Radiographic Sign Predictive of Chronic Peroneal Tendon Subluxation-Dislocation in Pes Planovalgus.

BACKGROUND. Tearing of the superior peroneal retinaculum is a known cause of peroneal tendon subluxation-dislocation. However, with the exception of cortical avulsions at the fibular attachment, superior peroneal retinaculum injury and subsequent peroneal tendon subluxation-dislocation are typically radiographically occult. OBJECTIVE. The purpose of this study was to evaluate the previously undescribed association between radiographic fibular tip periostitis and MRI evidence of peroneal tendon subluxation-dislocation in patients with hindfoot valgus. METHODS. Thirty-five patients with radiographic fibular tip periostitis and 35 ageand sex-matched individuals without periostitis were selected from among 220 consecutively registered patients with hindfoot valgus who had undergone both ankle radiography and MRI. Studies were retrospectively assessed by two musculoskeletal radiologists in consensus and by two additional blinded radiologists independently for the presence of peroneal tendon subluxation-dislocation, presence of subfibular impingement, and hindfoot valgus angle measurements. Interobserver agreement and accuracy, sensitivity, and specificity in the detection of fibular periostitis, peroneal tendon subluxation-dislocation, and subfibular impingement were calculated, and Fischer exact, Mann-Whitney, kappa coefficient, and intraclass correlation tests were performed. RESULTS. Both the consensus and the two independent interpretations showed that the frequency of peroneal tendon subluxation-dislocation was significantly greater in the group with periostitis (62.9%, 65.7%, and 85.7%) than in the group without periostitis (5.7%, 0%, and 14.3%) (p < .001). The finding of periostitis was specific and highly sensitive for predicting peroneal tendon subluxation-dislocation. The frequency of subfibular impingement was also statistically higher in the group with periostitis than in the group without it (p < .001). The hindfoot valgus angle was statistically larger in the group with periostitis than in the control group (p = .01-.002) and among patients with versus those without peroneal tendon subluxation-dislocation (p = .002 to p < .001). The blinded readers had substantial or almost perfect agreement on all imaging interpretations (concordance rate, 82.9-95.7%; κ = 0.66-0.91). CONCLUSION. The radiographic finding of fibular tip periostitis in patients with hindfoot valgus can be a predictor of peroneal tendon subluxation-dislocation and may also suggest advanced hindfoot valgus and subfibular impingement. These radiographic associations should be recognized by the radiologist, and MRI may be recommended as clinically indicated. CLINICAL IMPACT. Chronic undiagnosed peroneal tendon subluxation-dislocation can be a persistent cause of lateral ankle pain, leading to further degeneration and the possibility of complete peroneal tendon tears. Distal fibular periostitis in patients with hindfoot valgus can be a reliable radiographic indicator of this entity and may suggest the presence of subfibular impingement.

Reconstruction of Concomitant Ruptures of Peroneus Longus and Brevis Tendons: A Case Report and Literature Review.

Peroneal tendon ruptures are caused by inversion trauma of the ankle and are often mistaken for simple ankle sprains. As a result, peroneal tendon ruptures are underdiagnosed; especially a concomitant rupture of both the brevis and longus tendons is extremely rare. We describe the case of concomitant rupture of both peroneal tendons in a 50-year-old male, diagnosed with magnetic resonance imaging and treated with a flexor digitorum longus tendon transfer. The flexor digitorum longus tendon was mobilized, transferred laterally, and anchored to the distal and proximal stubs of the peroneal tendons, acting like a bridge. At final follow-up (19 months after index surgery), the patient was relieved from his symptoms and had full range of motion. Imaging demonstrated a durable reconstruction. Evidence for the preferred surgical treatment is lacking in the current literature and is limited to small case series and case reports. Randomized prospective studies should be conducted to determine the optimal treatment. Based on current available data, surgical technique should be based on clinical observation (e.g., tendon quality) and imaging findings.

The role of the immune system in tendon healing: a systematic review.

INTRODUCTION: The role of the immune system in tendon healing relies on polymorphonucleocytes, mast cells, macrophages and lymphocytes, the 'immune cells' and their cytokine production. This systematic review reports how the immune system affects tendon healing. SOURCES OF DATA: We registered our protocol (registration number: CRD42019141838). After searching PubMed, Embase and Cochrane Library databases, we included studies of any level of evidence published in peer-reviewed journals reporting clinical or preclinical results. The PRISMA guidelines were applied, and risk of bias and the methodological quality of the included studies were assessed. We excluded all the articles with high risk of bias and/or low quality after the assessment. We included 62 articles assessed as medium or high quality. AREAS OF AGREEMENT: Macrophages are major actors in the promotion of proper wound healing as well as the resolution of inflammation in response to pathogenic challenge or tissue damage. The immune cells secrete cytokines involving both pro-inflammatory and anti-inflammatory factors which could affect both healing and macrophage polarization. AREAS OF CONTROVERSY: The role of lymphocytes, mast cells and polymorphonucleocytes is still inconclusive. GROWING POINTS: The immune system is a major actor in the complex mechanism behind the healing response occurring in tendons after an injury. A dysregulation of the immune response can ultimately lead to a failed healing response. AREAS TIMELY FOR DEVELOPING RESEARCH: Further studies are needed to shed light on therapeutic targets to improve tendon healing and in managing new way to balance immune response.

Heterotopic Ossification After an Achilles Tendon Rupture Cannot Be Prevented by Early Functional Rehabilitation: A Cohort Study.

BACKGROUND: Tendon loading might play a role in the development of heterotopic ossification after Achilles tendon ruptures. Early heavy loading on a healing tendon in animals has been shown to prolong the proinflammatory response, and inflammatory cells are thought to drive heterotopic ossification formation. Taken together, this suggests that early rehabilitation might influence heterotopic ossification development. QUESTIONS/PURPOSES: The purposes of this study were to investigate (1) whether the presence of heterotopic ossification after Achilles tendon ruptures influences clinical outcome and (2) whether early mobilization or weightbearing prevents the development of heterotopic ossification. METHODS: This was a retrospective analysis of 69 patients from a previous clinical trial. All patients were treated surgically, but with three different early rehabilitation protocols after surgery: late weightbearing and ankle immobilization, late weightbearing and ankle mobilization, and early weightbearing and ankle mobilization. Plain radiographs taken 2, 6, 12, 26, and 52 weeks postoperatively were analyzed for heterotopic ossification, which was detected in 19% of patients (13 of 69) at 52 weeks. Heterotopic ossification was measured, scored, and correlated to clinical outcomes; heel-raise index (HRI), ankle joint ROM, tendon strain, Achilles tendon rupture score (ATRS), and Victorian Institute of Sport Assessment-Achilles (VISA-A) questionnaire scores at 26 and 52 weeks postoperatively. RESULTS: Heterotopic ossification had no adverse effects on patient-reported outcomes (ATRS or VISA-A), tendon strain, or ROM. In fact, patients with heterotopic ossification tended to have a better HRI at 52 weeks compared with patients without (mean difference 14% [95% CI -0.2 to 27]; p = 0.053). Neither the occurrence (heterotopic ossification/no heterotopic ossification) nor the heterotopic ossification severity (ossification score) differed between the three rehabilitation groups. Seventeen percent of the patients (four of 24) with early functional rehabilitation (early weightbearing and ankle joint mobilization exercise) had heterotopic ossification (score, 2-3) while late weightbearing and immobilization resulted in heterotopic ossification in 13% of the patients (score, 3-4). CONCLUSIONS: Heterotopic ossification occurs relatively frequently after Achilles tendon ruptures but appears to have no adverse effects on functional outcomes. Furthermore, heterotopic ossification develops during the first 6 weeks after rupture, and weightbearing or ankle-joint mobilization does not prevent this from occurring. LEVEL OF EVIDENCE: Level III, prognostic study.

No functional differences in anatomic reconstruction with one vs. two suture anchors after non-simultaneous bilateral distal biceps brachii tendon rupture: a case report and review of the literature.

BACKGROUND: Surgical reattachment of the tendon is still the gold standard for ruptures of the distal biceps brachii tendon. Several fixation techniques have been described in the literature, with suture anchors being one of the most common fixation techniques. Currently, there is no data available on how many anchors are required for a safe and stable refixation. In this case report clinical data of a patient with non-simultaneous bilateral distal biceps tendon ruptures treated with a different number of suture anchors for each side (one vs. two) are demonstrated. CASE PRESENTATION: A 47-year-old factory worker suffered a rupture of the distal biceps tendon on both arms following two different occasions. The left side was fixed using a single suture anchor, while refixation on the right side was performed with two anchors. The patient was prospectively followed for one year. Functional outcome was assessed using the Andrews Carson Score (ACS), the Oxford Elbow Score (OES), and the Disabilities of Arm, Shoulder and Hand (DASH) Score after six, twelve, 24 and 48 weeks. Furthermore, an isokinetic strength measurement for flexion strength was performed after 24 and 48 weeks. After 48 weeks the patient presented with excellent functional outcome scores and no follow-up complications. During the follow-up period, no differences in the functional scores nor in the isokinetic flexion strength measurement could be detected. Furthermore, no radiological complications (like heterotopic ossifications) could be detected in the postoperative radiographs after one year. CONCLUSIONS: Anatomic reattachment of the distal biceps tendon is a successful operative treatment option for distal biceps tendon ruptures. Suture anchor fixation remains one of the most common techniques, as it allows fast surgery and provides good results with respect to range of motion (ROM) and functional scoring according to the current literature. However, the number of anchors required for a stable fixation remains unclear. As indicated by our presented case, we hypothesize, that there are no significant differences between a one-point or a two-point fixation. In the presented case report, no intraindividual differences between the usage of one versus two suture anchors were evident in the short-term follow-up.

The backward traction test: a new and effective test for diagnosis of biceps and pulley lesions.

BACKGROUND: The value of physical examination for diagnosis of lesions of the long head of the biceps (LHB) and the pulley remains unsatisfactory. The purpose of this study was to describe a new diagnostic test, the backward traction (BT) test, to detect lesions of the LHB and the biceps pulley. METHODS: A prospective study of 143 patients was performed to evaluate the diagnostic value of the BT test and 2 traditional clinical tests (Speed and Yergason tests). Shoulder arthroscopy was used as the "gold standard." RESULTS: For the detection of LHB injury, the BT test was the most sensitive (74%) and accurate (68%). The BT test had a higher diagnostic value for pulley lesions, with a high sensitivity of 81% and an accuracy of 71%. No significant differences in terms of specificity for LHB and pulley lesions were observed between tests. Regarding pulley lesions, the internally rotated and externally rotated BT test positions had high specificity for the diagnosis of specific anteromedial and posterolateral pulley lesions (79% and 73%, respectively). The BT test had a high κ coefficient of 0.768-0.811. CONCLUSION: The BT test is more sensitive and accurate as a new test for LHB and pulley lesions and also specific to distinguish the medial sling and lateral sling lesions of the pulley.

Chronic distal biceps avulsion treated with suture button.

BACKGROUND: Distal biceps tendon avulsions account for 3%-10% of all biceps ruptures. Treated nonoperatively, these injuries lead to a loss of endurance, supination strength, and flexion strength compared with operative repair or reconstruction. Operative management of chronic injury has classically been with graft tissue to augment the contracted muscle. We present our results for chronic distal biceps avulsions secured with suture button through a single transverse incision in high flexion without the need for allograft augmentation. MATERIALS AND METHODS: This was a retrospective review of 20 patients with 21 injuries who underwent primary surgical repair of chronic distal biceps tendon avulsions at an average of 10 weeks (range 4-42 weeks). All patients were treated with a single transverse incision with a suture button armed with nonabsorbable no. 2 core sutures. Postoperatively patients were found to have 50°-90° flexion contracture. All patients were placed in a simple sling postoperatively with gentle extension to gravity as tolerated immediately and no formal physical therapy. Patients were surveyed regarding pre- and postoperative American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score, visual analog scale (VAS) score, Mayo Elbow Performance Score (MEPS), Oxford Elbow Score (OES), and overall satisfaction. Range of motion (ROM), flexion, and supination strength compared to the contralateral uninjured extremity were evaluated at final follow-up. RESULTS: Mean clinical follow-up was 26 months. All patients regained full ROM and 5/5 flexion and supination strength at final follow-up. MEPSs were 100 for all responding patients compared with an average 47.5 preoperatively (P < .0001). The mean postoperative ASES score was 97.2 compared with 41.9 preoperatively (P < .0001). Mean OESs pre- and postoperatively were 24.2 and 48, respectively (P < .0001). The mean VAS score was 4.4 preoperatively and was reported as 0 by all patients at final follow-up (P < .0001). Two patients had transient sensory radial nerve neuropathy, and 1 patient has persistent palsy. No synostoses occurred. Four patients reported supination fatigue postoperatively compared with the uninjured extremity. CONCLUSION: Given these results, we feel that chronic distal biceps tendon ruptures can be repaired successfully with a single incision using suture button technique without the use of a graft. Though the flexion contracture is significant postoperatively, all patients regained full ROM and had excellent postoperative functional outcome scores.