Long term results after bipolar radial head arthroplasty.

Radial head fractures are common injuries, occurring mostly in active young people 85%. Treatment of the more complex radial head fractures (Mason type III and IV), appear to be challenging and remain a subject of controversy. Replacement of the radial head with a metal prosthesis imitates the stabilizing role of the radial head and has been considered as the treatment of choice. However, long-term results are scarce. We report our mid to long-term (mean 9.4 year) clinical and radiographic results after insertion of a Judet Bipolar Radial Head prosthesis. 34 patients were treated with the Judet Bipolar Head prosthesis between 2000 and 2008. In this study, 21 patients were re-examined after a mean period of 113 months (range, 174-84), ie, 9.4 years (range, 14.5-7). Follow-up examinations included both the Mayo Elbow Performance Index (MEPI) and Dis- abilities of the arm, shoulder and hand (DASH) score. Range of motion was measured with a hand goniometer. X-rays were evaluated for peri-articular ossifications, radiolucent lines and signs of proximal erosion, capitellar erosion. Mean Mayo Elbow Performance Index was 88.6 (Range 100-50). According to the MEPI score we had 14 excellent, 1 good, 5 fair results and one poor result. One patient reported severe pain, 3 patients reported moderate pain, one patient reported mild pain and 16 patients reported no pain at all. Difference between pronation-suppination range was noted between primary or secondary indication of the radial head, no other significant differences were found. Mean DASH score was 23.1° (Range 0-63) without difference between primary and secondary indication. Mean flexion was 121.8° (Range : 110-140), mean extension deficit was 24.8° (Range 15-40), mean pronation was 62.4° (Range : 50-80) and suppination 58.8° (Range : 45-80). Ten patients showed signs of ulnohumeral joint degenerative arthritis. One patient developed symptomatic ulna plus. One patient showed radiolucent lines surrounding the prosthesis with proximal bone erosion. There were no reports of dislocations of the prosthesis. One case of radiological signs of overlenghtening was noted. Mainly good clinical results are achieved with the -Judet bipolar radial head implant. Functional results after long term follow-up are, however less optimistic then the excellent results achieved after short- to mid-term follow-up. No clear link between radiological signs and functional results can be found.

Does infrapatellar fat pad resection in total knee arthroplasty impair clinical outcome? A systematic review.

INTRODUCTION: The infrapatellar fat pad (IPFP) is often removed during total knee arthroplasty (TKA). No evidence based guidelines on changes in clinical outcome have yet been described. The aim of this review is to investigate whether regular removal of the IPFP during TKA should be performed. MATERIAL AND METHODS: Seven databases were systematically searched. Clinical studies, in which TKA with IPFP resection was compared with IPFP preservation, were included. Risk of bias was assessed using the Cochrane collaboration tool. Studies reporting anterior knee pain, patellar tendon length, range of motion, patellar vascularisation or functional outcome were included. RESULTS: The indication for TKA varied in the different studies: osteoarthritis (OA), rheumatic arthritis (RA) and multiple indications (OA, RA and osteonecrosis). After IPFP resection: 1. For OA, no differences in function, range of motion, and anterior knee pain were found. 2. In the RA study, there was a trend towards more discomfort and a decrease in function. 3. In OA and RA patients a decrease in patellar tendon length was observed. 4. One study reported no decrease in patellar vascularisation. DISCUSSION: Limitations of this review are the high risk of bias scores of the included studies, the varying outcome measures, follow up, number and type of participants. Randomised clinical trials are required to support or refute the results, contributing to a possible future evidence based guideline on IPFP resection during TKA.

Statin use is associated with reduced incidence and progression of knee osteoarthritis in the Rotterdam study.

BACKGROUND: Osteoarthritis is the most frequent chronic joint disease causing pain and disability. Besides biomechanical mechanisms, the pathogenesis of osteoarthritis may involve inflammation, vascular alterations and dysregulation of lipid metabolism. As statins are able to modulate many of these processes, this study examines whether statin use is associated with a decreased incidence and/or progression of osteoarthritis. METHODS: Participants in a prospective population-based cohort study aged 55 years and older (n=2921) were included. x-Rays of the knee/hip were obtained at baseline and after on average 6.5 years, and scored using the Kellgren and Lawrence score for osteoarthritis. Any increase in score was defined as overall progression (incidence and progression). Data on covariables were collected at baseline. Information on statin use during follow-up was obtained from computerised pharmacy databases. The overall progression of osteoarthritis was compared between users and non-users of statins. Using a multivariate logistic regression model with generalised estimating equation, OR and 95% CI were calculated after adjusting for confounding variables. RESULTS: Overall progression of knee and hip osteoarthritis occurred in 6.9% and 4.7% of cases, respectively. The adjusted OR for overall progression of knee osteoarthritis in statin users was 0.43 (95% CI 0.25 to 0.77, p=0.01). The use of statins was not associated with overall progression of hip osteoarthritis. CONCLUSIONS: Statin use is associated with more than a 50% reduction in overall progression of osteoarthritis of the knee, but not of the hip.

Tears of the supraspinatus tendon: assessment with indirect magnetic resonance arthrography in 67 patients with arthroscopic correlation.

BACKGROUND: Magnetic resonance (MR) arthrography is generally regarded as the gold standard for shoulder imaging. As an alternative to direct MR arthrography, the less invasive indirect MR arthrography technique was proposed, offering logistic advantages because fluoroscopic or ultrasonographic guidance for joint injection is not required. PURPOSE: To assess the diagnostic performance of indirect MR arthrography in the diagnosis of full- and partial-thickness supraspinatus tears in a symptomatic population. MATERIAL AND METHODS: Two radiologists with different levels of experience independently and retrospectively interpreted indirect MR (1.5T) arthrograms of the shoulder obtained in 67 symptomatic patients who underwent subsequent arthroscopy. On MR, the supraspinatus tendon was evaluated for full- or partial-thickness tear. With arthroscopy as the standard of reference, sensitivity, specificity, and diagnostic accuracy of indirect MR arthrography in the detection of full- and partial-thickness tears of the supraspinatus tendon was calculated. Kappa (kappa) statistics were used for the assessment of the agreement between arthroscopic and imaging findings and for the assessment of interobserver agreement. RESULTS: For full-thickness tears of the supraspinatus tendon, sensitivities, specificities, and accuracies exceeded 90% for both observers, with excellent interobserver agreement (kappa = 0.910). For partial-thickness tears, sensitivities (38-50%) and accuracies (76-78%) were poor for both reviewers, and interobserver agreement was moderate (kappa = 0.491). Discrepancies between MR diagnosis and arthroscopy were predominantly observed with small partial-thickness tears. CONCLUSION: Indirect MR arthrography is highly accurate in the diagnosis of full-thickness rotator cuff tears. However, the diagnosis of partial-thickness tears with indirect MR arthrography remains faulty, because exact demarcation of degenerative change and partial rupture is difficult. On the basis of the above findings, we do not recommend indirect MR arthrography on patients for whom rotator cuff disease is suspected clinically.

A common reference frame for describing rotation of the distal femur: a ct-based kinematic study using cadavers.

The understanding of rotational alignment of the distal femur is essential in total knee replacement to ensure that there is correct placement of the femoral component. Many reference axes have been described, but there is still disagreement about their value and mutual angular relationship. Our aim was to validate a geometrically-defined reference axis against which the surface-derived axes could be compared in the axial plane. A total of 12 cadaver specimens underwent CT after rigid fixation of optical tracking devices to the femur and the tibia. Three-dimensional reconstructions were made to determine the anatomical surface points and geometrical references. The spatial relationships between the femur and tibia in full extension and in 90 degrees of flexion were examined by an optical infrared tracking system. After co-ordinate transformation of the described anatomical points and geometrical references, the projection of the relevant axes in the axial plane of the femur were mathematically achieved. Inter- and intra-observer variability in the three-dimensional CT reconstructions revealed angular errors ranging from 0.16 degrees to 1.15 degrees for all axes except for the trochlear axis which had an interobserver error of 2 degrees . With the knees in full extension, the femoral transverse axis, connecting the centres of the best matching spheres of the femoral condyles, almost coincided with the tibial transverse axis (mean difference -0.8 degrees , sd 2.05). At 90 degrees of flexion, this femoral transverse axis was orthogonal to the tibial mechanical axis (mean difference -0.77 degrees , sd 4.08). Of all the surface-derived axes, the surgical transepicondylar axis had the closest relationship to the femoral transverse axis after projection on to the axial plane of the femur (mean difference 0.21 degrees , sd 1.77). The posterior condylar line was the most consistent axis (range -2.96 degrees to -0.28 degrees , sd 0.77) and the trochlear anteroposterior axis the least consistent axis (range -10.62 degrees to +11.67 degrees , sd 6.12). The orientation of both the posterior condylar line and the trochlear anteroposterior axis (p = 0.001) showed a trend towards internal rotation with valgus coronal alignment.

Validation of the lesser sigmoid notch of the ulna as a reference point for accurate placement of a prosthesis for the head of the radius: a cadaver study.

We undertook a study on eight arms from fresh cadavers to define the clinical usefulness of the lesser sigmoid notch as a landmark when reconstructing the length of the neck of the radius in replacement of the head with a prosthesis. The head was resected and its height measured, along with several control measurements. This was compared with in situ measurements from the stump of the neck to the proximal edge of the lesser sigmoid notch of the ulna. All the measurements were performed three times by three observers acting independently. The results were highly reproducible with intra- and interclass correlations of > 0.99. The mean difference between the measurement on the excised head and the distance from the stump of the neck and the lesser sigmoid notch was -0.02 mm (-1.24 to +0.97). This difference was not statistically significant (p = 0.78). The proximal edge of the lesser sigmoid notch provides a reliable landmark for positioning a replacement of the radial head and may have clinical application.

The effect of the orientation of the radial head on the kinematics of the ulnohumeral joint and force transmission through the radiocapitellar joint.

Background. The treatment of radial head fractures that are not amenable to an open reduction and internal fixation, remains to be a difficult issue. A potential problem with prosthetic replacement of the radial head is the shape of current radial head prostheses. The purpose of this study was to determine the effect of the shape of the radial head on kinematics and load transfer of the elbow. Methods. Kinematics of the elbow and radiocapitellar force transmission were measured in 6 fresh frozen upper extremities. The effect of radial head shape was tested by rotating the head 90 degrees , with a custom-made 'native' radial head prosthesis. 3-D spatial orientation of the ulna showed an average difference in ulnohumeral laxity, between the nominal and 90 degrees conditions, of 0.1 degrees throughout the arc of motion with neutral forearm rotation (maximum: 2 degrees ). Findings. We found an average difference in ulnar axial rotation, of 0.1 degrees (maximum: 1.9 degrees ). No differences showed statistical significance. Radiohumeral joint force was measured and maximally showed a 32 times increase of force in the altered shape conditions. Interpretation. Our results show that the kinematics of the elbow was not affected by altering the shape of the radial head, but it did adversely affect the forces in the radiohumeral joint. This could possibly generate degenerative changes in the elbow.

The kinematic importance of radial neck length in radial head replacement.

Comminuted radial head fractures can be treated with a radial head implant. The effects of lengthening (2.5 mm, 5 mm) and shortening (2.5 mm, 5 mm) of the radial neck, were compared to the nominal length in six human upper extremity cadavers. Total varus-valgus laxity and ulnar rotation were recorded. We hypothesized that restoring the exact length of the radius is important to maintain normal kinematics in the elbow joint. Lengthening or shortening of more than 2.5 mm significantly changed elbow kinematics. Lengthening caused a significant decrease (p < 0.001) in varus-valgus laxity, with the ulna tracking in varus and external rotation. Shortening caused a significant increase in varus-valgus laxity (p < 0.001) and ulnar rotation (p < 0.001), with the ulna tracking in valgus and internal rotation. Our study suggests that a restoration of radial length is important and that axial understuffing or overstuffing the radiohumeral joint by 2.5 mm or more, will alter elbow kinematics.

Detrimental effects of overstuffing or understuffing with a radial head replacement in the medial collateral-ligament deficient elbow.

BACKGROUND: Comminuted radial head fractures associated with an injury of the medial collateral ligament can be treated with a radial head implant. We hypothesized that lengthening and shortening of the radial neck would alter the kinematics and the pressure through the radiocapitellar joint in the medial collateral ligament-deficient elbow. METHODS: The effects of lengthening (2.5 and 5 mm) and shortening (2.5 and 5 mm) of the radial neck were assessed in six human cadaveric upper extremities in which the medial collateral ligament had been surgically released. The three-dimensional spatial orientation of the ulna was recorded during simulated active motion from extension to flexion. Total varus-valgus laxity and ulnar rotation were measured. Radiocapitellar joint pressure was assessed with use of pressure-sensitive film. RESULTS: Radial neck lengthening or shortening of >/=2.5 mm significantly changed the kinematics in the medial collateral ligament-deficient elbow. Lengthening caused a significant decrease (p < 0.05) in varus-valgus laxity and ulnar rotation (p < 0.05), with the ulna tracking in varus and external rotation. Shortening caused a significant increase in varus-valgus laxity (p < 0.05) and ulnar rotation (p < 0.05), with the ulna tracking in valgus and internal rotation. The pressure on the radiocapitellar joint was significantly increased after 2.5 mm of lengthening. CONCLUSIONS: This study suggests that accurate restoration of radial length is important and that axial understuffing or overstuffing of the radiohumeral joint by >/=2.5 mm alters both elbow kinematics and radiocapitellar pressure. CLINICAL RELEVANCE: This in vitro cadaver study indicates that a radial head replacement should be performed with the same level of concern for accuracy and reproducibility of component position and orientation as is appropriate with any other prosthesis.

Anatomical considerations of the radius.

Most radial head prostheses do not seem to be based on anatomic data. This may be due partly to the great variation of radial morphology. More importantly, few articles report on the dimensions of the radius. Authors have mainly studied dimensions of the radial head, with less emphasis to the relationship with the rest of the radius. Dimensions of, and relationship between, the proximal and the rest of the radius were measured on 27 fresh-frozen cadaveric upper extremities. Radial head, articulating surface, diaphysis, and distal radius were measured. Angles between the radial neck and diaphysis were defined and calculated. Axes of the distal and proximal radius were defined and radial torsion was calculated. Repeated measures were done by two observers in ten specimens. Inter- and intra-class correlation coefficients were very acceptable. Radial dimensions were found to be highly variable. Calculation of radial torsion showed the largest range. The average torsion was 54 degrees (range = 23-78 degrees). Radial length was 235 mm (range = 207-269 mm). Radial neck length was 13 mm (range = 9-19 mm). We found an average proximal diaphysis-neck angle of 17 degrees (range = 6-28 degrees). End to end-neck angle was 13 degrees (range = 4-22 degrees). Our findings indicate that even with a perfectly anatomical prosthesis, restoration of the anatomical situation can only be achieved when the implant is placed in the correct position. Instrumentation should be developed to allow accurate and reproducible implantation. The measurements we provide may aid this development.

The effect of the orientation of the noncircular radial head on elbow kinematics.

OBJECTIVE: The objective of this study was to identify the effect of radial head shape and orientation on elbow kinematics in the otherwise intact elbow. DESIGN: Biomechanical study, analyzing simulated active motion of cadaveric arms. BACKGROUND: A discrepancy exists between the noncircular anatomy of the radial head and radial head prostheses. The effect of radial head shape is unknown. METHODS: Kinematic effects of radial head shape were tested in six fresh-frozen upper extremities. A custom-made native radial head prosthesis was used to simulate altered shape conditions, by rotating the radial head 90 degrees. Three-dimensional spatial orientation of the ulna was recorded, during simulated active motion. A three factor ANOVA was used to compare (a) nominal and 90 degrees oriented conditions, (b) throughout the flexion arc (c) in three forearm positions (P < 0.05). Post-hoc Tukey tests were done to assess significance. RESULTS: No significant effect of altering radial head shape was found on total ulnohumeral laxity and angulation during gravity valgus stress. We did find a significant effect on total ulnar axial rotation and rotation during gravity valgus stress. CONCLUSION: The outer shape of the radial head seems to change rotation of the ulna during flexion-extension in an otherwise intact elbow. RELEVANCE: The shape of the radial head effects intact elbow kinematics. Clinical importance of this finding is clear. If a sub-optimally placed radial head prosthesis were to be used in an otherwise intact elbow, the elbow could be at risk for early ulnohumeral arthritis.

Arthroscopic subacromial decompression for advanced (stage II) impingement syndrome: a study of 52 patients with five years follow-up.

The authors report a prospective five-year follow-up study of 52 patients who had arthroscopic subacromial decompression for advanced (stage II: type 1 and 2) rotator cuff disease. All patients were assessed preoperatively, at six months and at five years postoperatively using the Constant-Murley score and the revised American Shoulder and Elbow Surgeons (ASES) score. From six months until five years postoperatively, 45 (out of 52) patients showed a further progressing improvement and relief of symptoms. This is established by a significant (p < 0.001) increase of the mean Constant-Murley score from 76.4 at six months postoperatively to 84.9 at five years postoperatively.

Arthroscopically assisted reduction and internal fixation of tibial plateau fractures: report of twenty cases.

The purpose of this study was to evaluate the results of arthroscopically assisted reduction and internal fixation of tibial plateau fractures. We report on 20 patients with 20 fractures with a mean follow-up time of 39 months (27-64 months). All fractures were evaluated according to the Schatzker classification. Under arthroscopic guidance, the fractures were reduced and associated intra-articular lesions were addressed appropriately. For split fractures a limited lateral approach, or the joystick technique, was used. Depression fractures were reduced with the aid of an anterior cruciate ligament (ACL) tibial guide. Postoperatively, immediate mobilisation and continuous passive motion was encouraged. A hinged brace provided stability and the patients were not allowed to bear weight for at least six weeks. According to the Rasmussen grading system, 18 out of 20 patients scored an excellent (15 patients), or a good (3 patients) result. One patient had a fair result. The only poor result we noted was caused by the fact that we were unable to reduce the fracture arthroscopically and had to perform an arthrotomy. We experienced no complications due to the arthroscopic procedure.

Current concepts in the treatment of radial head fractures in the adult. A clinical and biomechanical approach.

The treatment of simple radial head fractures type Mason-Hotchkiss 1 and 2 is unequivocal. In the case of a displacement of less than 2 mm (Mason-Hotchkiss 1), functional conservative treatment is indicated. If the displacement is more than 2 mm (Mason-Hotchkiss 2) internal fixation is indicated, combined with treatment of the soft-tissue injuries. The treatment of comminuted radial head fractures Mason-Hotchkiss type 3 is more controversial, as they are usually associated with ligament injuries. Conservative treatment appears to have unsatisfactory results. Opinions differ on surgical treatment, i.e. 1) excision of the radial head; 2) reconstruction by means of internal fixation; 3) excision and reconstruction with a prosthesis. Basic experimental research on human cadaver elbows shows the importance of the conservation of the radial head, especially in case of associated soft tissue injuries. In most cases a stable osteosynthesis is impossible, and in case of associated ligament disruptions, resection and reconstruction by means of a rigid radial head prosthesis should be considered. Experimental research demonstrates promising results for rigid radial head prostheses in human cadaver elbows with a resected radial head and failing medical collateral ligament. Short-term clinical studies seem to confirm this, but long-term results are as yet unknown.

The floating radial head prosthesis for comminuted radial head fractures: a multicentric study.

We report our experience with the floating radial head prosthesis of Judet for comminuted fractures of the radial head. We present the results in 15 patients with a mean follow-up of 25.2 months. Thirteen prostheses were inserted for acute Mason III fractures of the radial head, and 2 were inserted for chronic problems after radial head fracture. According to the Mayo Elbow Performance Index there were 7 excellent, 3 good, 1 fair and 2 poor results in the group with acute injuries. In this group, one prosthesis was removed after 8 months for severely decreased elbow function. In the group with chronic problems, there were 2 fair results. There were no dislocations or prosthesis fractures. None of the prostheses showed signs of loosening. Three patients in the acute group developed wrist pain, and in one patient in the chronic group, preexisting wrist pain disappeared after insertion of the radial head prosthesis. Our short-term results suggest that the floating radial head prosthesis is a suitable solution for early or delayed treatment of Mason type III fractures, either isolated or associated with more complex injuries.

Bilateral patellar tendon rupture: case report and literature review.

Bilateral patellar tendon rupture is a rare entity, often associated with systemic diseases. We report the case of a 67-year-old man with bilateral ruptures of the patellar tendons caused by minor trauma and with a good functional end result.