Reverse shoulder arthroplasty as a salvage procedure for failed conventional shoulder replacement due to cuff failure--midterm results.

Our goal was to evaluate the objective and subjective midterm outcome after revision of a failed shoulder arthroplasty with a reverse design prosthesis. Twenty consecutive patients with 21 revisions of a primary shoulder arthroplasty using reverse shoulder prosthesis Delta III(®) were followed up postoperatively for a mean of 46 months including clinical and radiological examination. Complications were recorded and Constant score, DASH and SF36 were assessed. With the numbers given a significant reduction of pain was achieved from 8.7 to 3.0 (p < 0.001). There was a significant improvement of active flexion from 43° to 97° (p < 0.001) and active abduction from 44° to 90° (p < 0.001). However, at the same time, active external rotation with an adducted humerus decreased significantly from 26° to 12° (p = 0.012). The constant score improved significantly from 16.7 to 55.9 (p < 0.001). Sixteen patients (84%) rated their shoulder better or much better than before. In 43% an intraoperative and in 38% a postoperative complication occurred including two late stage infections which required prosthesis removal. Our results support the use of the reverse prosthesis as revision prosthesis. The reverse design helps to compensate functional deficits due to severe soft-tissue damage except active external rotation. Nevertheless, the revision is a technically demanding procedure reflected in a high rate of intraoperative complications. The rate of secondary infections of 10% remains a special concern.

Biomechanical testing of rectangular humeral shaft prosthesis: higher torsional stability without increased fracture risk.

BACKGROUND: Rectangular cementless femur shaft prostheses have a higher primary stability than round shafts. A novel rectangular humeral shaft design was tested with two questions: does the rectangular design cause a higher fracture risk during implantation than round designs, and does it increase the torsional stiffness? MATERIALS AND METHODS: Two series with six paired human humeri (total 24) were tested on one side with the rectangular shaft and on the contralateral side with a round shaft. In the first series, the shaft implantation was carried out with a constant speed of 100 mm/min and the maximum force was measured when the fracture occurred. In the second series, the implants were preloaded with 50 N and then rotated at 2° per second with monitoring of the torsional torque. RESULTS: The maximum force at fracture showed no significant difference for the two designs (p = 0.34). Higher age and low bone density reduced the force required for fracture. The rectangular shaft showed significant higher torsional moments (p < 0.05). CONCLUSIONS: In biomechanical testing, the rectangular shaft had a significantly higher primary torsional stability than the round shaft without a higher risk of fracture during cementless implantation. Fracture risk and torsional stability are influenced by age and bone density.

Relationship between tendon structure, stiffness, gait patterns and patient reported outcomes during the early stages of recovery after an Achilles tendon rupture.

After an Achilles tendon (AT) injury, the decision to return to full weightbearing for the practice of sports or strenuous activities is based on clinical features only. In this study, tendon stiffness and foot plantar pressure, as objective quantitative measures that could potentially inform clinical decision making, were repeatedly measured in 15 patients until 3 months after the AT rupture by using shear wave elastography (SWE) and wearable insoles, respectively. Meanwhile, patient reported outcomes assessing the impact on physical activity were evaluated using the Achilles Tendon Total Rupture Score (ATRS). At week-2 post-injury, stiffness of the injured tendon varied from 6.00 ± 1.62 m/s (mean ± SD) close to the rupture to 8.91 ± 2.29 m/s when measured more distally. While near complete recovery was observed in distal and middle regions at week-8, the shear wave velocity in the proximal region recovered to only 65% of the contralateral value at week-12. In a parallel pre-clinical study, the tendon stiffness measured in vivo by SWE in a rat model was found to be strongly correlated with ex vivo values of the Young's modulus, which attests to the adequacy of SWE for these measures. The insole derived assessment of the plantar pressure distribution during walking showed slight sub-optimal function of the affected foot at week-12, while the ATRS score recovered to a level of 59 ± 16. Significant correlations found between tendon stiffness, insole variables and distinct ATRS activities, suggest clinical relevance of tendon stiffness and foot plantar pressure measurements. These results illustrate how an alteration of the AT structure can impact daily activities of affected patients and show how digital biomarkers can track recovery in function over time.

Arthroscopic and open options for surgical treatment of chondromatosis of the elbow.

PURPOSE: The purpose of this study was to evaluate the treatment-specific outcome of surgical therapy of chondromatosis of the elbow with special attention on the complication and recurrence rate as well as induction of secondary osteoarthritis. METHODS: A consecutive patient group from 1989 to 2003 was evaluated retrospectively and followed up clinically and radiologically. Special attention was paid to locking and catching, swelling, pain, loose bodies, and signs of osteoarthritis. In the case of a causal pathology, mostly osteoarthritis, the condition was classified as secondary; otherwise, it was classified as primary. The following scores were calculated: modified American Shoulder and Elbow Surgeons questionnaire for elbows; Disabilities of the Arm, Shoulder and Hand questionnaire; and Short Form 36. RESULTS: Of 24 patients operated on, 19 (79%) were followed up after 56 months (range, 11 to 177 months). Of these, 10 were primary types and 9 secondary types. The extension deficit of 12 degrees preoperatively decreased to -9 degrees , and pain was significantly (P = .001) reduced. Postoperatively, 1 patient still reported occasional locking and 1 patient had swelling. In both patients no loose bodies could be identified by radiography. Comparison of the arthroscopic and open techniques showed a trend toward a shorter rehabilitation time of 2.4 months after arthroscopic intervention, in contrast to 4.6 months for an open procedure, and a trend toward higher patient satisfaction after arthroscopy. Comparison of the primary and secondary forms showed significantly (P = .042) better pain reduction for primary chondromatosis. Of the patients with distinct preoperative osteoarthritis, 44% showed ongoing osteophytic growth; there were no cases of new osteoarthritis. CONCLUSIONS: Both open and arthroscopic approaches give satisfactory results with a trend toward shorter rehabilitation and higher patient satisfaction for the arthroscopic approach. Osteoarthritis is not induced and there is no danger of recurrence in the medium term. LEVEL OF EVIDENCE: Level III, therapeutic, retrospective comparative study.

Does Weber's rotation osteotomy induce degenerative joint disease at the shoulder in the long term?

Weber's internal rotation osteotomy of the humeral head is recommended for the treatment of anteroinferior shoulder instability with a large Hill-Sachs defect. The observation of severe joint degeneration in the course of long-term follow-up provided the motivation for this study. An osteotomy was performed in 42 patients from 1984 to 1990. Thirty-four patients were available for clinical and radiological follow-up after 14.5 years. Our own CT-based classification was applied to categorize the degree of osteoarthritis. A shoulder prosthesis was implanted in 9 patients (26%). Only 3 patients (9%) did not show any signs of degeneration. A statistically significant relationship was found between increased internal rotation of the humeral head and disease severity (P = .03). A lower incidence of joint degeneration (P = .02) was found for patients with generalized ligamentous laxity. We therefore recommend this osteotomy only as a salvage procedure whereby the internal rotation of the humeral head should not exceed 20 degrees .

Expert Consensus on Predictive Parameters for the Occurrence of a Fall and a Contralateral Hip Fracture 1 and 3 Years After Hip Fracture: A Delphi Survey.

BACKGROUND: Early identification of people at risk for a contralateral hip fracture would be desirable to favorably influence patients' prognosis. A recent systematic review failed to depict stringent patterns of risk parameters to be used for decision-making in clinical practice. OBJECTIVE: To perform a consensus study using the Delphi method to reach an expert consensus on predictive parameters for the occurrence of a fall and a contralateral hip fracture 1 and 3 years after hip fracture. METHODS: A list of potential members of the expert panel was identified based on the authors' list of a recently conducted systematic review. Participating experts were asked to name parameters determining the probability for a fall and a contralateral hip fracture 1 and 3 years after an occurred hip fracture, separately. Additionally, we asked how those stated parameters should be measured. All mentioned parameters were compiled and sent back to the experts asking them to weight each single parameter by assigning a number between 1 (not important) and 10 (very important). The survey was conducted online using the REDCap software package. We defined expert agreement if the interquartile range of attributed weights for a parameter was ≤2. A relevant parameter had at least a median weight of 8. RESULTS: Twelve experts from 7 countries completed the survey. Presence of fall history and mental and general health status were considered relevant irrespective of the outcome. For falling within 1 and 3 years, the number of medications and residential status were considered relevant, while for fractures within 1 and 3 years, osteoporosis management was considered important. CONCLUSION: Using the insights gained in this consensus study, empiric studies need to be set up assessing the prognostic value of the selected parameters.

Significant Differences Between Local Reporting and Central Assessment of Radiographic Complications in a Prospective, Multicenter Study About Locking Plate Fixation of Proximal Humerus Fractures.

OBJECTIVES: To compare reporting outcomes of radiographic complications conducted by an independent review board and the responsible on-site study personnel in a multicenter study about locking plate fixation of proximal humeral fractures. DESIGN: Prospective, multicenter study; setting: 9 level I trauma centers. PATIENTS: One hundred fifty patients (age 50-90) with a radiographically confirmed displaced proximal humeral fracture fixed with a locking plate were included in the study. INTERVENTION: All radiographic data were reevaluated by an independent review board according to predefined criteria. MAIN OUTCOME MEASUREMENTS: Differences in outcomes between the review board and the on-site assessment were analyzed with a paired t test. Interrater agreements between the central review board and on-site assessments were estimated by means of kappa statistics. RESULTS: The review board revealed significantly more radiographic complications than the on-site assessment (P = 0.006), except for the complication "head necrosis." The interrater agreement was slight to moderate in all calculated categories. CONCLUSIONS: Implementation of a complication review board using predefined criteria is recommended for clinical studies to prevent underreporting of radiographic complications by on-site assessment.

Parameters Pointing at an Increased Risk for Contralateral Hip Fractures: Systematic Review.

BACKGROUND: Early identification of hip fracture (HF) patients bearing an increased risk for a contralateral occurrence would allow providing preventive measures timely. OBJECTIVES: To summarize the available evidence describing risk scores, prognostic instruments, or (groups of) parameters predicting contralateral HFs at the time point of the first fracture. Methods/Systematic Review: Articles were identified through searches in MEDLINE and Scopus from inception to April 2014, checking of reference lists of the included studies and reviews. One reviewer assessed all articles for inclusion and abstracted the data. Uncertain cases were discussed and decided with a second reviewer. Salient study and population characteristics were abstracted for each article. Studies reporting the association of a set of risk factors for second HFs were further examined and compared. The number of studies reporting on a risk parameter was assessed. RESULTS: Searches identified 3560 records, and 47 studies were included in this review. There was a large spectrum of study designs, patient populations, and follow-up periods. Among 11 studies reporting on a set of parameters, female gender was assessed most commonly (7 times), followed by age (5) and parameters of general health, vision, and stroke (each 4 times). We were unable to depict stringent patterns of risk parameters to be used for decision making in clinical practice. CONCLUSIONS: The findings of this article call for a conjoint effort to achieve an expert consensus regarding a critical set of parameters for a risk instrument identifying patients bearing an increased risk for contralateral HFs early.

Significant differences between local reporting and central assessment of radiological complications in a prospective, multicenter study about locking plate fixation of proximal humerus fractures.

OBJECTIVES: To compare radiological complication reporting outcomes undertaken by an independent review board and the responsible on-site study personnel in a multicenter study about locking plate fixation of proximal humeral fractures. DESIGN: prospective, multicenter study SETTING:: Level I trauma centers PATIENTS:: One-hundred and fifty patients with a radiological confirmed, closed, displaced proximal humeral fracture fixed with a locking plate and aged between fifty and ninety years. INTERVENTION: Re-evaluation of all radiological data according to pre-defined criteria after finished collection of all study radiographs by an independent review board. MAIN OUTCOME MEASUREMENTS: Differences in outcomes between the review board and the sites assessment were tested with a paired t-test. Inter-rater agreements between the central review board and sites assessments were estimated by means of kappa statistics. RESULTS: The review board revealed significant more radiological complications than the sites assessment (p = 0.006), except for the complication 'head necrosis'. The inter-rater agreement was slight to moderate in all calculated categories. CONCLUSIONS: To prevent underreporting of radiological complications by on-site assessment, the implementation of a complication review board, using pre-defined criteria, is recommended for clinical studies that focus on radiological complications.

Mechanical stability in a human radius fracture treated with a novel tissue-engineered bone substitute: a non-invasive, longitudinal assessment using high-resolution pQCT in combination with finite element analysis.

The clinical gold standard in orthopaedics for treating fractures with large bone defects is still the use of autologous, cancellous bone autografts. While this material provides a strong healing response, the use of autografts is often associated with additional morbidity. Therefore, there is a demand for off-the-shelf biomaterials that perform similar to autografts. Biomechanical assessment of such a biomaterial in vivo has so far been limited. Recently, the development of high-resolution peripheral quantitative computed tomography (HR-pQCT) has made it possible to measure bone structure in humans in great detail. Finite element analysis (FEA) has been used to accurately estimate bone mechanical function from three-dimensional CT images. The aim of this study was therefore to determine the feasibility of these two methods in combination, to quantify bone healing in a clinical case with a fracture at the distal radius which was treated with a new bone graft substitute. Validation was sought through a conceptional ovine model. The bones were scanned using HR-pQCT and subsequently biomechanically tested. FEA-derived stiffness was validated relative to the experimental data. The developed processing methods were then adapted and applied to in vivo follow-up data of the patient. Our analyses indicated an 18% increase of bone stiffness within 2 months. To our knowledge, this was the first time that microstructural finite element analyses have been performed on bone-implant constructs in a clinical setting. From this clinical case study, we conclude that HR-pQCT-based micro-finite element analyses show high potential to quantify bone healing in patients.

Challenges for Large Orthopaedic Hospitals Worldwide-An ISOC Position Statement.

Since the foundation of the International Society of Orthopaedic Centers in 2006, the group has continued to grow, with currently 11 members worldwide. During the 2008 annual meeting, the bylaws and mission of the group were approved as well as the acceptance of two additional members. Strict inclusion criteria were established to keep the group both small and effective. The goal of the 2008 meeting and this position statement is to identify current challenges in both research and education for large-volume orthopedic hospitals and to discuss possible approaches and solutions.

Sports activity after anatomical total shoulder arthroplasty.

BACKGROUND: Implant functionality has clearly increased over the past decades because of improvements in total shoulder arthroplasty systems. This means that prostheses are now being implanted in younger patients with high sports activity. HYPOTHESIS: The implantation of the total shoulder arthroplasty does not mainly influence the sports activity. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: One hundred consecutive patients with unilateral total shoulder arthroplasty, followed for at least 1 year, were included in the study. Assessment preoperatively and 1 year and 2 years after operation included clinical examination and a validated questionnaire (Constant, Shoulder Pain and Disability Index [SPADI], and Disabilities of the Arm, Shoulder and Hand [DASH] scores, and the Short Form 36 [SF-36]). In addition, all patients received a sports questionnaire developed in house. RESULTS: Of the 55 patients who took part in sports before having shoulder disease, 49 (89%) were still able to participate after a mean follow-up of 2.8 years (range, 1.3-4.6 years). Seventeen patients had given up sports before total shoulder arthroplasty; 11 of them resumed activities after joint replacement but 6 did not start again. No patient had to stop sports because of the total shoulder arthroplasty. The sports most commonly mentioned were swimming (10 patients [20.4%]), golf (8 patients [16.3%]), cycling (8 patients [16.3%]), and fitness training (8 patients [16.3%]). Strength and range of motion, as well as the physical component summary (PCS) of the SF-36 and the Constant score (CS) after total shoulder arthroplasty, were significantly better in the sports group (49 of 100; PCS = 46, CS = 77) than in the nonsports group (45 of 100; PCS = 41,CS = 71). Eighteen patients (36.7%) stated that even after joint replacement, they still suffered restrictions on their sports activities because of shoulder problems. Whereas the overall mean age at follow-up was 68.9 years (range, 26-92 years), the mean age of patients participating in sports was significantly lower than in the nonsports group (63 vs 70 years; P = .002). CONCLUSION: Total shoulder arthroplasty allows patients to participate in sports without significant restriction of their level of activity. The probability of being able to do sports postoperatively-if done preoperatively-is high. Long-term studies are needed to determine whether the greater loading on the joint will lead to more rapid wear and a higher rate of loosening with time.

Return to sports and recreational activity after unicompartmental knee arthroplasty.

BACKGROUND: There is a lack of detailed information concerning patients' sports and recreational activities after unicompartmental knee arthroplasty. HYPOTHESIS: Patients treated by unicompartmental knee arthroplasty will be able to return to sports and activity. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: The authors surveyed 83 patients by postal questionnaires to determine their sporting and recreational activities at a mean follow-up of 18 +/- 4.6 months (range, 12-28) after unicompartmental knee arthroplasty. For data analysis, patients were divided into groups of women and men, and older and younger patients (those above and below the median age of the group). The authors also assessed the state of general health (SF-36) of the patients at the time of the survey and compared the results with those of a matched (for age and side-diagnoses) reference population. RESULTS: Before surgery, 77 of 83 patients were engaged in an average of 5.0 sports and recreational disciplines; postoperatively, 73 (88%) participated in an average of 3.1 different sports disciplines, resulting in a return to activity rate of 95%. The frequency of activities (sessions per week) was 2.9 preoperatively and remained constant at the time of survey (2.8). The group of older patients (mean age 73.0 y) revealed a significantly higher frequency than the group of younger patients (mean age 57.8 y). The minimum session length decreased from 66 minutes before surgery to 55 minutes after surgery. The most common activities after surgery were hiking, cycling, and swimming. Several high-impact activities, as well as the winter disciplines of downhill- and cross-country skiing had a significant decrease in participating patients. The majority of the patients (90.3%) stated that surgery had maintained or improved their ability to participate in sports or recreational activities. The patients generally scored very high on the SF-36 compared with the matched reference population. Higher SF-36 values in the physical-related domains correlated with an increased level of activity (r = 0.425). The preoperative body mass index showed a weak, negative correlation with the postoperative extent of activities (r = -0.282). CONCLUSION: The majority of patients returned to sports and recreational activity after unicompartmental knee arthroplasty. However, the numbers of different disciplines patients were engaged in decreased as well as the extent of activities. The activities in which most patients participated were primarily low- or midimpact. The patients scored higher on the SF-36 than age-related norms, which might be due to the patient-selection process for unicompartmental knee arthroplasty and geographical differences.

Influence of screw positioning in a new anterior spine fixator on implant loosening in osteoporotic vertebrae.

STUDY DESIGN: A biomechanical study was designed to assess implant cut-out of three different angular stable anterior spinal implants. Subsidence of the implant relative to the vertebral body was measured during an in vitro cyclic loading test. OBJECTIVES: The objective of the study was to evaluate two prototypes (Synthes) of a new anterior spine fixator with different screw angulations in comparison to the established MACSTL(R) Twin Screw Concept (Aesculap). The influence of factors like load-bearing cross-sectional area, screw angulation and bone mineral density upon implant stability should be investigated. SUMMARY OF BACKGROUND DATA: Epidemiologic data predict a growing demand for appropriate anterior spinal fixation devices especially in patients with inferior structural and mechanical bone properties. Although different concepts for anterior spinal instrumentation systems have been tried out, implant stability is still a problem. METHODS: Three angular stable, anterior spinal implants were tested using 24 human lumbar osteoporotic vertebrae (L1-L5; age 84 (73-92)): MASC TL system (Aesculap); prototype 1 (MP1) with 18 degrees and prototype 2 (MP2) with 40 degrees screw angulation (both Synthes). All implants consisted of two screws with different outer screw diameters: 7-mm polyaxial screw with 6.5-mm stabilization screw (MASC TL), two 5-mm locking-head screws each (MP1 and MP2). Bone mineral density (BMD) and vertebral body width of the three specimen groups were evenly distributed. The specimens were loaded in craniocaudal direction (1Hz) for 1000 cycles each at three consecutive load steps; 10-100 N, 10-200 N and 10-400 N. During cyclic loading subsidence of the implant relative to the vertebral body was measured in the unloaded condition. Cycle number at failure (defined as a subsidence of 2 mm) was determined for each specimen. A survival analysis (Cox Regression) was performed to detect differences between implant groups at a probability level of 95%. RESULTS: High correlations were found between BMD and number of cycles until failure (MP1; r = 0.905, P = 0.013; MP2: r = 0.640, P = 0.121; MACS TL: r = 0.904, P = 0.013) and between load bearing cross sectional area and number of cycles until failure (MP1: r = 0.849, P = 0.032;MP2: r = 0.692, P = 0.085; MACS TL: r = 0.902, P = 0.014). Both Prototypes survived significantly longer than the MACS TL implant (MP1: P = 0.012, MP2: P = 0.014). The survival behaviour of MP1 and MP2 was not significantly different (P = 0.354). CONCLUSIONS: Implant stability within each implant group was influenced by BMD and load bearing cross-sectional area. The angulation of the two screws did not have a significant influence on cut-out. As conclusion from this study, promising approaches for further implant development are: 1) increase of load-bearing cross-sectional area (e.g., larger outer diameter of the anchorage device), 2) screw positioning in areas of higher BMD (e.g., opposite cortex, proximity to pedicles or the endplates).