Risk factors for periprosthetic femoral fracture risk around a cemented polished taper-slip stem using an osteoporotic composite bone model

This biomechanical study aimed to determine if variations in stem material, stem geometry, stem offset and cement viscosity affect mechanical resistance to postoperative periprosthetic fracture (PFF) after hip arthroplasty with a commonly used cemented polished taper-slip (PTS) stem (CPT, Zimmer Biomet) in a novel osteoporotic composite femoral bone model. Thirty-six osteoporotic composite femoral models were tested using a standardised in-vitro loading technique to simulate a typical PFF. Outcome measures were torque to failure (N), fracture energy (N/m2) and rotation to failure (°). Comparisons were made by stem material (cobalt chrome vs stainless steel), stem geometry (CPT stem vs Exeter stem), stem offset (standard offset vs extra extended offset) and cement viscosity (high viscosity vs low viscosity). Statistical comparisons were carried out with significance set at p < 0.05. All tested samples produced clinically representative fracture patterns with varying degrees of bone and cement comminution. There was no statistically significant difference in torque to failure, fracture energy or rotation to failure between any of the compared variables (all p > 0.05). This is the first biomechanical study on mechanical resistance to PFF using osteoporotic composite bone models. For the CPT stem, it confirms that stem material, stem offset, stem geometry and cement viscosity do not affect mechanical resistance to PFF in an osteoporotic bone model.

Lean Mass, Muscle Strength, and Muscle Quality in Retired Rugby Players: The UK Rugby Health Project

Although athletes from sports such as rugby have greater lean mass and strength during their playing careers, little is known about these characteristics post-retirement. Therefore, this study investigated lean mass, strength, and muscle quality in retired elite and amateur rugby players and non-contact athletes. Retired elite male rugby players (n=42, 43.9±10.3 y; 101.1±13.4 kg; 1.82±0.09 m), amateur rugby players (n=46, 48.0±10.5 y; 98.9±16.6 kg; 1.79±0.07 m) and non-contact athletes (n=30, 51.3±12.5 y; 91.3±13.4 kg; 1.79±0.07 m) received one total body dual-energy X-ray absorptiometry assessment of appendicular lean mass (ALM) and ALM index (ALMI). Grip strength was measured, and muscle quality (grip strength/unit of arm lean mass) was calculated. Sarcopenia was identified as ALMI<7.23 kg/m² and handgrip strength<37.2 kg. Total lean mass, ALM and grip strength were greater in the elite rugby compared to amateur rugby and non-contact groups (p<0.01). There were no significant differences in muscle quality or sarcopenia prevalence. Retired elite rugby players had greater lean mass and grip strength than amateur rugby and non-contact athletes, although muscle quality was similar. The greater lean mass and strength might reflect genetic influences or previous participation in a highly physical sport.

Cumulative Sport-Related Injuries and Longer Term Impact in Retired Male Elite- and Amateur-Level Rugby Code Athletes and Non-contact Athletes: A Retrospective Study

Background

Rugby union and rugby league are popular team contact sports, but they bring a high risk of injury. Although previous studies have reported injury occurrence across one or several seasons, none have explored the total number of injuries sustained across an entire career. As the first to do so, the aim of this study was to report on cumulative injuries and their perceived long-term impact in retired rugby code athletes compared to athletes from non-contact sports.

Methods

One hundred and eighty-nine former rugby code athletes (rugby union n = 145; rugby league n = 44) and 65 former non-contact athletes were recruited to the UK Rugby Health Project between September 2016 and December 2018. Details on sports participation, sports injuries and concussion history, sports injury-related surgeries, and previous and current health were obtained from a validated, online self-report questionnaire.

Results

Former elite rugby code athletes (n = 83) reported more total injuries per player (median 39, IQR 35) than former amateur rugby code athletes (n = 106; median 23, IQR 30; p = 0.014) and non-contact sports athletes (n = 65; median 7.5, IQR 15; p < 0.001). Concussion was the most frequently reported injury for the elite and amateur rugby code groups, followed by upper/lower back and knee ligament injuries. These injuries also presented with the highest recurrence. Rugby code groups reported a higher continued impact of previous concussion, neck injuries, shoulder dislocation, ACL tears, and knee ligament injuries (p = 0.003–0.045). The reported prevalence of osteoarthritis was more than twofold greater in the elite rugby code group than in non-contact athletes (51% v 22%, p < 0.001). The prevalence of back pain and/or severe and regular joint pain was high across all groups (47–80%), particularly the elite rugby code group. The total number of joint injuries and sport injury-related surgeries was higher in those who reported current osteoarthritis and current severe and regular joint pain (p < 0.001–p = 0.028).

Conclusion

Across multiple injury types, past participation in rugby union and rugby league, particularly at elite level, is associated with a high cumulative injury load and a continued impact of previous injuries post-retirement. Given the high number of reported concussions (and their recurrence) and associations between previous injuries during a player’s career and current musculoskeletal conditions, efforts should be prioritized to reduce the occurrence and recurrence of injuries in rugby codes at all levels of the sport. Strategies should also be developed for supporting the specific physical health needs of rugby code athletes post-retirement.

Electronic supplementary material

The online version of this article (10.1007/s40279-020-01310-y) contains supplementary material, which is available to authorized users.

Vertebral Anomalies in Retired Rugby Players and the Impact on Bone Density Calculation of the Lumbar Spine

Dual energy X-ray absorptiometry (DXA) lumbar spine bone mineral density (BMD) measurements are subject to artificial elevation in the presence of structural abnormalities that are more common with age and injury, including osteoarthritis, fracture and osteophytes. The aims of this study were to investigate the presence of vertebral abnormalities on DXA scans in retired rugby players and a nonrugby control group, and to explore the effect of vertebral exclusion on the BMD diagnostic outcome. Eigty-seven male retired rugby players and 51 non-rugby controls from the UK Rugby Health Project participated in the study. Lumbar spine, total hip and femoral neck BMD were measured by DXA and scans were analyzed pre and post exclusion of anomalous vertebrae. Data were analyzed by age group to enable application of T-scores (≥50 y) and Z-scores (<50 y). From 138 lumbar spine scans, 66 required adjustment. One hundred twenty-two vertebral exclusions were made, and 12 lumbar spine scans (10 in retired rugby athletes) were un-reportable (<2 evaluable vertebrae). Vertebral exclusion significantly lowered lumbar spine BMD across all groups (p<0.01) and lowered the overall lowest T/Z-score. This effect was more pronounced in rugby groups (age <50 y, p < 0.001; age ≥50 y, p = 0.031) than in the control groups (age <50y, p = 0.125; age ≥50 y, p = 0.250). Vertebral abnormalities detected on lumbar spine scans, were highly prevalent and impacted final the T/Z-score in this cohort of retired rugby players. Current guidelines recommend exclusion of abnormalities from lumbar spine scans in adults aged ≥50 years. Our findings suggest that vertebral exclusions should also be applied to lumbar spine scans performed in those aged <50 years, particularly in former contact sports athletes, given their high risk for vertebral deformity.

Clinical evaluation of education relating to nutrition and skeletal loading in competitive male road cyclists at risk of relative energy deficiency in sports (RED-S): 6-month randomised controlled trial

Objective

To clinically evaluate education to improve eating behaviour and skeletal loading exercise in male cyclists at risk of poor bone health and impaired performance due to relative energy deficiency in sports.

Methods

Early race season, 50 competitive male road cyclists were matched, in pairs, based on Z-scores for lumbar spine bone mineral density (BMD). One member of each pair was randomly allocated to receive educational interventions. After the season, 45 cyclists returned for dual-energy X-ray absorptiometry scans and blood tests. Least significant change was applied to identify clinically meaningful BMD changes. Cyclists completed a follow-up sport-specific questionnaire and clinical interview to ascertain adherence to the interventions.

Results

The questionnaire and clinical interview categorised behaviour changes as positive, negative or unchanged. Positive changes in nutrition and skeletal loading were associated with a statistically significant increase of 2.0% in lumbar spine BMD; 7 of 11 cyclists’ increases were clinically meaningful. Negative changes in both behaviours were associated with a significant decrease of 2.7% in lumbar BMD; all nine cyclists’ BMD decreases were clinically meaningful. Regarding performance, taking account of functional threshold power, changes in nutritional behaviour accounted for gains or losses of 95 British Cycling racing points. Cyclists reported psychological barriers to change in behaviours, specifically fear of negatively impacting performance.

Conclusions

Educational nutritional and skeletal loading interventions can improve bone health, well-being and race performance in male cyclists over a 6-month race season. Psychological support may be required to help some athletes change behaviour.