The effect of subscapularis repair in reverse total shoulder arthroplasty depends on the design of the implant: a comparative study with a minimum 2-year follow-up.

INTRODUCTION: The role of the subscapularis (Ssc) tendon does not yet have a well-defined role in RSA. The purpose of the present study was to evaluate if the repair of the Ssc in RSA improves overall clinical and radiographic results and if it has the same results using a medialized design humeral stem compared to a lateralized design. METHODS: Eighty-four consecutive patients undergoing RSA were retrospectively analyzed. Nine patients were lost at FU. Two implants with similar glenosphere design and different stem design (medialized and lateralized) were used. The Ssc was repaired in case of good quality of the fibers and reducibility without tension intraoperatively. Patients were divided into four groups for data analysis depending on whether they had received a medialized or lateralized design and Ssc repair or not. Patients were reviewed at an average follow-up of 40.8 ± 13.1 months. Clinical outcome measures included Active range of motion (ROM), strength, visual analog scale (VAS), Constant-Murley score (CMS), and the American Shoulder and Elbow Surgeons score (ASES). Radiographic evaluation at final follow-up was performed to assess scapular notching, stress shielding, and radiolucent lines. RESULTS: No statistically significant clinical differences (p > 0.05) emerged between Lat/Ssc+ and Lat/Ssc-. Conversely, the patients belonging to the Med/Ssc- group reported statistically worse (p < 0.05) results than the Med/Ssc + group in terms of VAS, ASES and CMS. Statistically worse (p < .05) results in the Med/Ssc- group than in the Med/Ssc + were found also in active ROM achieved in FE, ABD, ER1 and ER2, and in the strength obtained in FE, ABD and ER2. Scapular notching was reported in 3 shoulders (15.7%) in Lat/Ssc+ group and in 7 shoulders (50%) in Lat/Ssc- group, while it was reported in 4 shoulders (14.2%) in Med/Ssc + group and in 6 shoulders (42.8%) in Med/Ssc- group. Stress shielding was observed in 6 cases in Lat/Ssc+ group (31.6%), in 8 cases in Lat/Ssc- group (57.1%), in 3 cases (10.7%) in Med/Ssc + group and 4 cases in Med/Ssc- group (28.6%). CONCLUSIONS: Patients undergoing RSA show clinical improvements at mid-term follow-up with a low rate of complications, regardless of the use of a medialized or a lateralized humeral stem design. Ssc repair is associated with better functional outcomes in the cohort of medialized stem, while it did not yield significant differences in the cohort of lateralized stem. LEVEL OF EVIDENCE: Level III; Retrospective Cohort Comparison; Treatment Study.

Comparative study of 145° onlay curved stem versus 155° inlay straight stem reverse shoulder arthroplasty: clinical and radiographic results with a minimum 2-year follow-up.

BACKGROUND: Lateralized onlay reverse shoulder arthroplasty (RSA) is designed to ensure better clinical functional recovery and lower rate of complications compared with Grammont medialized inlay RSA. The purpose of the present study was to compare the clinical and radiographic outcomes between these 2 different designs. METHODS: Eighty-five consecutive patients who underwent RSA were retrospectively analyzed. Nine patients were lost to follow-up, 34 received a curved onlay with a 145° neck-shaft angle (Ascend Flex group), and 42 received a long straight inlay stem with a 155° neck-shaft angle (Delta Xtend group). Patients were reviewed at an average follow-up of 46.8 ± 13.2 months (Ascend Flex group) and 36 ± 10.8 months (Delta Xtend group). Clinical outcome measures included active range of motion, strength, visual analog scale, Constant-Murley score, and the American Shoulder and Elbow Surgeons score. Radiographic evaluation at the final follow-up was performed to assess scapular notching, stress shielding, acromial or scapular fractures, heterotopic ossification, and radiolucent lines or implant loosening. RESULTS: No differences emerged between the 2 groups in terms of visual analog scale, American Shoulder and Elbow Surgeons and Constant-Murley scores, pain, function, strength, mobility, active forward elevation, active internal rotation, active external rotation at 0° and 90° of abduction, abduction, forward elevation, and external rotation strength (P = n.s.). Statistically superior active abduction was observed in the Delta Xtend group (P = .0017). Scapular notching was observed in 12 shoulders (35.2%) in the Ascend Flex group (a grade 1) and in 10 shoulders (23.8%) in the Delta Xtend group (P = n.s.). No differences emerged between the 2 groups in terms of humeral or glenoid radiolucency (P = n.s.). Higher rate of humeral stress shielding rate was observed in the Ascend flex cohort (P = n.s.). CONCLUSIONS: No statistically significant difference emerged between the 145° onlay curved stem vs. the 155° inlay straight stem according to most of the evaluated parameters. Statistically superior active abduction was observed in the 155° group although it did not affect patients' satisfaction.

Densitometric evaluation of bone remodelling around Trabecular Metal Primary stem: a 24-month follow-up.

BACKGROUND: Today, an increasing number of total hip arthroplasty (THA) procedures are being performed. Osseointegration is a physiological phenomenon that leads to the direct anchorage of an implant by the formation of bony tissue around the implant without the growth of fibrous tissue at the bone-implant interface. Several factors may affect this phenomenon: some of these depend on the patient and others may depend on implant design and materials. Variations in periprosthetic bone mineral density (BMD) can be studied through several scans by dual energy X-ray absorptiometry (DEXA) around the femoral stem. AIMS: The purpose of this study is to investigate correlations between periprosthetic BMD and the factors affecting osseointegration. METHODS: We retrospectively analysed patients who underwent primary THA. In all the patients, Trabecular Metal Primary (TMP), a standard uncemented tapered stem with a proximal porous tantalum coating, was implanted. Preoperatively, postoperatively, 3 and 6 months, 1 year and 2 years after implantation, DEXA scans were performed around the femoral stem. The patients were matched for diagnosis, sex, BMD of the lumbar spine and contralateral femur, Body Mass Index and age. RESULTS: One hundred and eight patients (51 males and 57 females) with a mean age of 73 years were studied. Different BMD changing patterns were observed and a greater bone resorption was noted in all the conditions associated with poor bone quality. DISCUSSION: The proximal coating of Trabecular Metal Primary (TMP) seemed to be effective in promoting new bone formation in the proximal femur also in the conditions associated with poor bone quality. CONCLUSIONS: At the present time, DEXA is considered the most reliable tool for evaluating bone remodelling after THA.

Fracture healing in elderly patients: new challenges for antiosteoporotic drugs.

Osteoporosis is a major public health concern, characterized by low bone mass and structural deterioration of bone tissue, leading to bone fragility and an increased susceptibility to fracture. Fracture repair progresses through different pathways, striking a balance between bone formation and bone remodeling mechanisms. Conventionally, fracture repair is divided into defined stages, each characterized by a specific set of cellular and molecular events. In postmenopausal women and elderly patients, bone healing rates are conditioned by cellular and molecular alterations to bone tissue that result in a progressive deterioration of fracture healing ability. In addition, in elderly patients, comorbidities and drugs therapies may also affect fracture healing. For this reason, pharmacological research is now focused on the possible use of antiosteoporotic drugs to promote bone healing in frail patients.

Bone healing and osteoporosis.

A correct fracture healing depends on the synergy between biomechanical, molecular and cellular factors. Focusing on different stages, fracture hematoma represents the starting point of the inflammatory process, with a critical role in triggering the process of fracture healing. The essential factors for bone repair are the activation of mesenchymal stem cells and the release of growth and regulatory factors. Moreover, the efficacy of fracture healing is determined by three ideal conditions: adequate blood supply, good contact between bone fragments and good stability. It is remarkable how the implant choice influences fracture healing after surgical treatment. In osteoporosis, bone quality adversely affects the tissue structural competence, increasing the risk of a complicated fracture healing. The qualitative and quantitative alterations established at the cellular level during osteoporosis explain the progressive deterioration of bone tissue healing ability.

Epidemiology of fragility fractures in Italy.

OBJECTIVES: We aimed to calculate the incidence of major fragility fractures in Italy, including those which do not result systematically in hospital admissions, on the basis of hospitalization rates provided in our previous researches. METHODS: We analyzed Italian national hospital discharge data from year 2004 to 2006 in order to determine age- and sex-specific incidence rates of hip, vertebral, humeral, and forearm fractures occurred in people aged 40 to 100 years of age. Re-hospitalizations of the same patients have been excluded from the analysis. Hospital discharge data have been adjusted taking into account recently published information concerning fracture-specific hospitalization rates. RESULTS: We estimated a total of 88,647 hip fractures in year 2006 among people aged 40 to 100 years old, with a +5.9% increase across the three examined years. Women aged >75 years old (n=53,259) accounted for 60% of total fractures observed both in males and females from 40 to 100 years of age. Concerning males, the highest incidence was observed between 80 and 84 years old (about 5,000 hip fractures). Overall incidence rate per 100,000 inhabitants computed for hip fractures was 284.28, with marked age- and sex-specific differences. Clinical vertebral fractures were estimated to be almost 61,000 in 2006, with a +3.1% increase across the three examined years. Overall incidence rate per 100,000 inhabitants computed for clinical vertebral fractures was 195.23, but this value doubled between 75 and 95 years of age. In the same year 2006, a total of 56,129 humeral and 97038 forearm/wrist fractures, with a +5.5% and +3.9% increase across three years, respectively. Overall humeral fractures incidence per 100,000 was 180, with highest rates (up to 600 and over) observed in women between 75 and 95 years of age, while incidence per 100,000 computed for wrist fractures was 311, with top values observed in women between aged 55-85 years old - thus including early post-menopausal age group - and a peak in those between 75 and 79 years of age. CONCLUSIONS: The burden of major osteoporotic fractures in Italy is very high. Preventive strategies aimed to reduce fractures incidence should be carried out at regional level.

Updated incidence rates of fragility fractures in Italy: extension study 2002-2008.

OBJECTIVES: We aimed to update the incidence rates of major fragility fractures in Italy, including those which do not result systematically in hospital admissions, on the basis of hospitalization rates provided in our previous researches. METHODS: We analyzed italian national hospital discharge data from year 2002 to 2008 in order to determine age- and sex-specific incidence rates of hip, vertebral, humeral, and forearm fractures occurred in people aged 40 to 100 years of age. Re-hospitalizations of the same patients have been excluded from the analysis. Hospital discharge data have been adjusted taking into account recently published information concerning fracture-specific hospitalization rates. RESULTS: We estimated a total of 91,494 hip fractures in year 2008 among people aged 40 to 100 years old, with a +18.1% increase across the seven-year period. Women aged >75 years old (n=55,950) accounted for about 60% of total fractures observed both in males and females. Concerning males, the highest incidence was observed between 80 and 84 years old (about 5,000 hip fractures). Overall incidence rate per 100,000 inhabitants computed for hip fractures was 283.5, with marked age- and sex-specific differences. Clinical vertebral fractures were estimated to be almost 61,000 in 2008, with a +6.3% increase over seven years. Overall incidence rate per 100,000 inhabitants computed for clinical vertebral fractures was 189.0, but this value doubled between 75 and 95 years of age. For the same year 2008, we estimated a total of 57,400 humeral and 94,000 forearm/wrist fractures, with a +13.2% and +0.7% increase over the seven-year period, respectively. Overall humeral fractures incidence per 100,000 was estimated in 178.0, with highest rates (up to 600 and over) observed in women between 75 and 95 years of age, while incidence per 100,000 for wrist fractures was computed in 298.0, with top values observed in women between aged 55 years old and over. CONCLUSION: The burden of major osteoporotic fractures in Italy is still increasing. Preventive strategies aimed to reduce fractures incidence should be carried out at regional level.

The incidence of hip, forearm, humeral, ankle, and vertebral fragility fractures in Italy: results from a 3-year multicenter study.

INTRODUCTION: We aimed to assess the incidence and hospitalization rate of hip and "minor" fragility fractures in the Italian population. METHODS: We carried out a 3-year survey at 10 major Italian emergency departments to evaluate the hospitalization rate of hip, forearm, humeral, ankle, and vertebral fragility fractures in people 45 years or older between 2004 and 2006, both men and women. These data were compared with those recorded in the national hospitalizations database (SDO) to assess the overall incidence of fragility fractures occurring at hip and other sites, including also those events not resulting in hospital admissions. RESULTS: We observed 29,017 fractures across 3 years, with hospitalization rates of 93.0% for hip fractures, 36.3% for humeral fractures, 31.3% for ankle fractures, 22.6% for forearm/wrist fractures, and 27.6% for clinical vertebral fractures. According to the analyses performed with the Italian hospitalization database in year 2006, we estimated an annual incidence of 87,000 hip, 48,000 humeral, 36,000 ankle, 85,000 wrist, and 155,000 vertebral fragility fractures in people aged 45 years or older (thus resulting in almost 410,000 new fractures per year). Clinical vertebral fractures were recorded in 47,000 events per year. CONCLUSIONS: The burden of fragility fractures in the Italian population is very high and calls for effective preventive strategies.

Pharmacological agents and bone healing.

Osteoporosis is the most common alteration of bone metabolism. It derives from an increase in bone resorption with respect to bone formation and is characterized by microarchitectural alterations, decreased bone mass and increased risk of fracture. The coupling between bone formation and resorption is a fundamental concept in skeletal metabolism, and it explains how a certain amount of removed tissue can be replaced by the same amount of new bone. Various substances used to treat osteoporosis may also be used for orthopaedic conditions such as fracture healing, implant fixation, bone grafts and osteonecrosis. Fracture healing consists in the replacement of the lost bone by a tissue that has the same biomechanical properties as those preceding the fracture. The repair process is triggered by the local response to the tissue injury that damaged the continuity of bone. The duration of each phase of the healing process can vary significantly, depending on the site and characteristics of the fracture, on patient related factors and on the treatment choice. While most of the fractures heal with conventional treatment, they can also cause permanent damage and complications, especially in a certain kind of patients. Osteoporosis and old age may contribute in delaying or impairing the reparative process. In animal models the healing process is slower in older and/or ovariectomized animals. Biomechanical tests have also shown that bone strength is compromised in human osteoporotic cadaver bone. The same problems were highlighted in the surgical treatment of fractures in osteoporotic patients. Mainly in the treatment of hip fractures there is an increased risk of cut-out, re-fractures and implant failure in patients with osteoporosis. Preclinical studies have shown that certain pharmacological agents (bisphosphonates, strontium ranelate, teriparatide) may enhance osseointegration and stimulate reparative processes. They may be administered systemically and/or used locally at the fracture site on the implant surface. The aim of fracture treatment is to restore bone biomechanical properties and to allow restoring normal function at the affected site. If the new pharmacological approaches could be translated into clinical benefit and offered to patients with osteoporosis or other factors that put at risk the process of healing (subjects with severe loss of substance or fractures at high risk of complications), they could represent a valuable aid in the treatment of fractures.