Preventive interventions for throwing injuries in baseball players: a scoping review.

BACKGROUND: Shoulder and elbow pain are the common complaints associated with throwing injuries in baseball players. Prospective studies evaluating the effectiveness of stretching in increasing posterior shoulder flexibility or strengthening the external rotator muscles as preventive strategies for throwing injuries in baseball players have been published. However, there are limited reviews highlighting the role of preventive interventions for throwing injuries in baseball players. Therefore, this scoping review aimed to summarize the existing literature on preventive interventions for throwing injuries in baseball players. METHODS: We searched the Cochrane Central Register of Controlled Trials, MEDLINE, and Scopus databases on 3 March 2023. Two independent reviewers screened the studies based on the eligibility criteria. We extracted existing literature on preventive interventions and effectiveness for throwing injuries in baseball players, and participants' characteristics and results were extracted from the studies. This scoping review was performed in accordance with the Extended Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement for Scoping Reviews. RESULTS: The initial database search yielded 1170 articles, four of which met the eligibility criteria. Of the included studies, two were randomized controlled trials, and the remaining two were prospective cohort studies. Eligible studies targeted youth-to high school-level players and focused on preventive programs for throwing injuries that manifest in the upper extremities of baseball players. The outcome measure most commonly used to quantify the effectiveness of prevention programs was the incidence of shoulder and elbow injuries, although the definitions vary among studies. The prevention program included sleeper stretching, shoulder external rotation strengthening exercises, and comprehensive prevention programs (focusing on improving the elbow, shoulder, and hip range of motion; rotator cuff and periscapular muscle strength; posture; and lower extremity balance). Each prevention program was reported to have the potential to reduce the incidence of throwing injuries in baseball players, and two studies suggested that high compliance with the program led to a lower injury risk. CONCLUSION: This scoping review confirmed the presence of studies that examined preventive interventions for throwing injuries in baseball players. Preventive interventions that may reduce throwing injuries in baseball players include sleeper stretching, shoulder external rotation strengthening exercises, and comprehensive prevention programs. However, the characteristics of participants (eg, age, sports level, and position) and the definition of injury varied among previous studies. Injury profiles and prevention strategies may differ according to age, sport level, and position of players, and more studies are needed to prove this issue.

Fracture of the oxidized zirconium femoral component after total knee arthroplasty.

BACKGROUND: Femoral component fracture is a rare complication of total knee arthroplasty (TKA). CASE: We report a case of oxidized zirconium (Oxinium) femoral component fracture after total knee arthroplasty. The fracture site was the junction of the central and medial flanges. The patellar component and polyethylene insert had delamination at the contact point of the fracture line, and the tibial tray had loosening at the medial side. There was no cement adherence at the component fracture site, suggesting that debonding had occurred at the cement-implant interface in this area. Examination with a scanning electron microscope revealed beach marks, which are characteristic findings of metal fatigue. CONCLUSION: We considered that the cause of femoral component fracture was a fatigue fracture due to poor fixation of the component to the bone caused by poor osteotomy technique or poor cementing technique. To our knowledge, this is the first case of Oxinium femoral component fracture.

Are there differences in arthroscopic and histological features between traumatic and degenerative rotator cuff tears in elderly patients? A prospective dual-center analysis.

BACKGROUND: Discriminating traumatic rotator cuff tears (RCTs) from degenerative RCTs is sometimes difficult in elderly patients because the prevalence of asymptomatic RCTs increases with age. Little intraoperative information is available on the characteristics of traumatic and degenerative RCTs in elderly patients. The purpose of this study was to compare the arthroscopic findings and histological changes of the coracoacromial ligament (CAL) between traumatic and degenerative RCTs in elderly patients. METHODS: Forty-two shoulders of 42 patients aged ≥ 65 years underwent arthroscopic rotator cuff repair. Nineteen patients had traumatic full-thickness RCTs (Group T), and 23 had degenerative full-thickness RCTs (Group D). The quality of the rotator cuff tissue and the condition of the long head of the biceps were examined. The grade of CAL was evaluated both arthroscopically and histologically. The stiffness of the musculotendinous unit was calculated by measuring the force and displacement using a tensiometer. The arthroscopic and histological findings of the two groups were compared. RESULTS: Although the mean tendon displacement was comparable, the stiffness was different between Group T and Group D (0.56 ± 0.31 and 1.09 ± 0.67 N/mm, respectively; p < 0.001). Both arthroscopic and histological analysis of the CAL showed that the degenerative changes in the CAL were milder in Group T than in Group D (p < 0.001 and p < 0.001, respectively). There was a moderate positive correlation between the arthroscopic findings of CAL degeneration and the histopathological changes in this ligament (r = 0.47, p = 0.002). CONCLUSIONS: Traumatic RCTs were characterized by preserved elasticity of the musculotendinous unit and milder CAL degeneration compared with degenerative RCTs even in elderly patients.

Clinical Outcomes According to Femoral and Acetabular Version After Periacetabular Osteotomy.

BACKGROUND: Patients with acetabular dysplasia often have abnormal femoral and acetabular version. The effect of combined femoral and acetabular version on clinical outcomes after periacetabular osteotomy for the treatment of acetabular dysplasia remains unclear. The purposes of the present study were (1) to evaluate the association of combined femoral and acetabular version with clinical outcome after periacetabular osteotomy and (2) to investigate the association of femoral version independently with clinical outcome after periacetabular osteotomy. METHODS: We retrospectively reviewed the records for 92 consecutive patients (95 hips) who had undergone periacetabular osteotomy for the treatment of symptomatic acetabular dysplasia. The patient cohort comprised 85 females and 7 males with a mean age of 38.9 years at the time of surgery. The mean duration of follow-up was 4.8 years (range, 2.0 to 7.2 years). Femoral and acetabular version and the alpha angle were measured on postoperative computed tomography scans. Clinical outcomes included range of motion and the modified Harris hip score. Analysis of variance was used to investigate the effect of femoral version on clinical outcomes. Analysis of covariance was used to adjust for potential covariates. RESULTS: Combined femoral and acetabular version after periacetabular osteotomy was slightly, but significantly, correlated with postoperative flexion (r = 0.222; p = 0.031) and internal rotation in flexion (r = 0.326; p = 0.001). Patients with mild femoral version (<15°) experienced significantly less postoperative internal rotation in flexion than those with severe femoral version (>35°); however, this difference was lost after adjustment for potential covariates. There were no differences among femoral version groups (mild, moderate, and severe) in terms of improvements in the clinical outcomes of pain, function, and activity. CONCLUSIONS: Combined femoral and acetabular version after periacetabular osteotomy was significantly correlated with postoperative range of motion. Abnormality of femoral version associated with acetabular dysplasia did not demonstrate any effect on the clinical outcomes of periacetabular osteotomy. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Preservation technique of the piriformis tendon is superior to reattachment technique in terms of contiguity and muscle atrophy: using magnetic resonance imaging.

PURPOSE: The preservation technique of the piriformis tendon during the posterolateral approach in total hip arthroplasty (THA) is reportedly superior to the reattachment technique in terms of dislocation. However, the long-term effects of preservation of the piriformis tendon during THA remain unknown. In this study, we evaluated the contiguity of the piriformis/conjoined tendon and atrophy of the piriformis/internal obturator muscle during a long-term postoperative follow-up using magnetic resonance imaging (MRI). METHODS: We retrospectively evaluated 48 patients with available MRI. The 48 patients were classified into a P group ( n = 29), in which the piriformis tendon was preserved, and an R group ( n = 19), in which the piriformis was reattached after sectioning. The mean follow-up duration was 45.9 months. The contiguity of the piriformis/conjoined tendon and atrophy of the piriformis/internal obturator muscle were evaluated in all patients. RESULTS: The piriformis tendon remained attached to the greater trochanter in all P-group patients and 68.4% of R-group patients. The mean piriformis muscle atrophy ratios were 15.9% ± 21.1% in the P group and 41.6% ± 19.1% in the R group ( p < 0.001). The conjoined tendon repair remained intact in 72.4% of P-group patients and 36.8% of R-group patients ( p < 0.05). The mean internal obturator muscle atrophy ratio was 31.4% ± 26.2% in the P group and 50.4% ± 19.1% in the R group ( p < 0.05). No postoperative pulmonary embolism, wound infection, deep infection, or hip dislocation occurred. CONCLUSIONS: In our study, we suggest that the preservation technique of the piriformis tendon is superior to the reattachment technique in terms of contiguity and muscle atrophy.

New cross-table lateral radiography method for measuring acetabular component anteversion in total hip arthroplasty: a prospective study of 93 primary THA.

INTRODUCTION: Various methods have been described for measuring acetabular component anteversion. However, accurate measurement of anteversion is difficult. We herein propose a new method using cross-table lateral (CL) radiography performed with the contralateral hip flexed to 45° (45° flexed CL radiography). The main purpose of this study was to evaluate the reliability and validity of this new method. METHODS: The study group included 93 patients who underwent total hip arthroplasty (THA). All hips were evaluated with computed tomography (CT) and both standard and 45° flexed CL radiographs to measure acetabular component anteversion the week after THA. The intraobserver and interobserver reliability of each measurement was assessed. Plain radiography measurements were compared with reference CT measurements to evaluate their validity. RESULTS: All measurements had excellent intraobserver and interobserver reliability, and plain radiography measurements correlated well with CT measurements. The mean measurements were 21.9° (3°-39°) with CT, 24.9° (7°-47°; p<0.001) with standard CL radiographs, and 22.5° (7°-43°; p = 0.112) with 45° flexed CL radiographs. DISCUSSION: The anteversion values measured with our new method were closer to the CT values used as a reference standard than those with standard CL radiographs. Our new method appears to be reliable and valid for measuring acetabular component anteversion.

Arthroscopic removal of an intra-articular osteoid osteoma of the radial styloid.

We describe a case of intra-articular osteoid osteoma arising in the radial styloid of a 21-year-old man. Plain radiographs were not diagnostic, but computed tomography, gadolinium-enhanced magnetic resonance imaging, and bone scintigraphy suggested the possibility of an osteoid osteoma. We arthroscopically removed the lesion; histological examination confirmed the diagnosis. The patient's symptoms disappeared immediately after surgery.