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Ross J.R.,University of Michigan | Bedi A.,University of Michigan | Stone R.M.,Minnesota Orthopedic Sports Medicine Institute | Enselman E.S.,University of Michigan | And 3 more authors.
American Journal of Sports Medicine | Year: 2014

Background: In the diagnosis and surgical treatment of cam-type femoroacetabular impingement (FAI), 3-dimensional (3D) imaging is the gold standard for detecting femoral head-neck junction malformations preoperatively. Intraoperative fluoroscopy is used by many surgeons to evaluate and verify adequate correction of the deformity. Purpose: (1) To compare radial reformatted computed tomography (CT) scans with 6 defined intraoperative fluoroscopic views before surgical correction to determine whether fluoroscopy could adequately depict cam deformity, and (2) to define the influence of femoral version on the clock-face location of the maximum cam deformity on these views. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: A consecutive series of 50 hips (48 patients) that underwent arthroscopic treatment for symptomatic FAI by a single surgeon were analyzed. Each patient underwent a CT scan and 6 consistent intraoperative fluoroscopy views: 3 views in hip extension and 3 views in hip flexion of 50°. The alpha angles of each of the fluoroscopic images were compared with the radial reformatted CT using a 3D software program. Femoral version was also defined on CT studies. Statistical analysis was performed using the Student t test, with P < .05 defined as significant. Results: Fifty-two percent of patients were male, average age 28 years (range, 15-56 years). The maximum mean alpha angle on fluoroscopy was 65° (range, 37°-93°) and was located on the anteroposterior (AP) 30° external rotation (ER) fluoroscopy view. In comparison, the mean CT-derived maximum alpha angle was 67° and was located at 1:15 (P = .57). The mean clock-face positions of each of the fluoroscopy views (standardized to the right hip) were AP 30° internal rotation, 11:45; AP 0° (neutral) rotation, 12:30; AP 30° ER, 1:00; flexion/00 (neutral) rotation, 1:45; flexion/40o ER, 2:15; and flexion/60o ER, 2:45. Increased femoral ante-version (>20°) was associated with a significant change in the location of the maximum alpha angle (1:45 vs 1:15; P = .002). Conclusion: The described 6 fluoroscopic views are very helpful in localization and visualization of the typical cam deformity from 11:45 to 2:45 and can be used to reliably confirm a complete intraoperative resection of cam-type deformity in most patients. These views correlate with preoperative 3D imaging and may be of even greater importance in the absence of preoperative 3D imaging. © 2014 The Author(s).


Dudli S.,ETH Zurich | Ferguson S.J.,ETH Zurich | Haschtmann D.,Schulthess Klinik
Spine Journal | Year: 2014

Background context The burst fracture of a vertebra is the result of a complex loading procedure and is often associated with intervertebral disc (IVD) degeneration. Likewise, the presumed etiologies are (i) the structural perturbation of the IVD/end plate, (ii) the impact of loading energy alone, and (iii) the depressurization of the nucleus pulposus. Purpose To describe the pathogenesis of post-traumatic disc degeneration (DD) by comparing the severity and patterns of degeneration with different injury models. Study design New data from an in vitro organ culture study are compared with the previous work on the same model system. Methods To investigate in detail the contribution of each factor (i-iii) to DD, we extended our previous work to compare three different segmental trauma processes in a rabbit full-organ in vitro model: burst fracture (Group A, etiologies i-iii), equienergetic loading without a fracture (Group B, ii), and endplate puncturing (Group C, iii). DD markers (apoptosis, necrosis, matrix remodeling, inflammation) were monitored up to 28 days posttrauma. Gene transcription data were subjected to principal component analysis and agglomerative hierarchical clustering to identify and compare pathologic patterns. Results Only Group A showed the full profile of DD: reduced glycosaminoglycan content, increased caspase-3/7 and lactate dehydrogenase (LDH) activity, and elevated messenger RNA of catabolic (matrix metalloproteinase-1, -3, -13) and proinflammatory (tumor necrosis factor-alpha, interleukin [IL]-6, IL-8, and monocyte chemotactic protein-1) genes. In Group B, only catabolic and proinflammatory genes were slightly upregulated. In Group C, LDH but not caspase-3/7 activity was increased. Catabolic and proinflammatory genes were upregulated, although less compared with Group A. Principal component analysis revealed different transcription patterns for Group C. Conclusions The structural perturbation of the end plate/IVD, but not the loading energy or nuclear depressurization, promotes DD. In addition, end-plate puncturing triggers a different pathogenesis, consistent with a more continuous matrix remodeling process. © 2014 Elsevier Inc. All rights reserved.


Zaltz I.,William Beaumont Hospital | Leunig M.,Schulthess Klinik
Clinical Orthopaedics and Related Research | Year: 2012

Background: Cam-type, pincer, and mixed femoroacetabular impingement (FAI) are accepted causes of labral and acetabular rim injury; however, the abnormal contact stresses associated with motion may damage other areas of the hip. Although cartilage damage to the femoral head has been reported previously in athletes, FAI-associated focal parafoveal chondral defects differ from previously reported lesions and represent a rare manifestation of the complex pathomechanics associated with FAI. Questions/Purposes: We describe the clinical, radiographic, and surgical characteristics of a rare focal anterolateral parafoveal femoral chondral defect associated with FAI. Methods: We retrospectively reviewed 10 patients with symptomatic FAI diagnosed with this unique focal defect confirmed at the time of surgical dislocation. Patients presented with hip pain, clinical findings of FAI, and, frequently, with an identifiable lesion on MRI arthrography. The minimum clinical followup was 12 months (mean, 29 months; range, 12-72 months). Results: The consistent characteristics of these lesions associated with FAI differ from previously reported femoral chondral damage reported after hip dislocation or lateral impact in that there was no discrete injury such as a fall or dislocation/subluxation, no associated traumatic femoral lesion, and all were localized to the posterosuperior femoral head. Eight of 10 were diagnosed preoperatively using MR arthrography. Conclusions: Despite radiographic similarities to findings of osteoarthritis and osteonecrosis, these FAI-associated femoral chondral defects were amenable to surgical reconstruction using first- or second-generation cartilage repair techniques during surgical treatment of impingement. The etiology of these lesions may be related to complex intraarticular forces generated by FAI-associated transient hip subluxation or forceful nonconcentric motion. Level of Evidence: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence. © The Association of Bone and Joint Surgeons® 2012.


Sink E.L.,Hospital for Special Surgery | Leunig M.,Schulthess Klinik | Zaltz I.,Oakland Orthopaedic Surgeons | Gilbert J.C.,Hospital for Special Surgery | Clohisy J.,Washington University in St. Louis
Clinical Orthopaedics and Related Research | Year: 2012

Background: Quality of health care and safety have been emphasized by various professional and governmental groups. However, no standardized method exists for grading and reporting complications in orthopaedic surgery. Conclusions regarding outcomes are incomplete without a standardized, objective complication grading scheme applied concurrently. The general surgery literature has the Clavien-Dindo classification that meets the above criteria. Questions/purposes: We asked whether a previously reported classification would show high intraobserver and interobserver reliabilities when modified for orthopaedic surgery specifically looking at hip preservation surgery. We therefore determined the interreader and intrareader reliabilities of the adapted classification scheme as applied to hip preservation surgery. Methods: We adapted the validated Clavien-Dindo complication classification system and tested its reliability for orthopaedic surgery, specifically hip preservation surgery. There are five grades based on the treatment required to manage the complication and the potential for long-term morbidity. Forty-four complication scenarios were created from a prospective multicenter database of hip preservation procedures and from the literature. Ten readers who perform hip surgery at eight centers in three countries graded the scenarios at two different times. Fleiss' and Cohen's κ statistics were performed for interobserver and intraobserver reliabilities, respectively. Results: The overall Fleiss' κ value for interobserver reliability was 0.887 (95% CI, 0.855-0.891). The weighted κ was 0.925 (95% CI, 0.894-0.956) for Grade I, 0.838 (95% CI, 0.807-0.869) for Grade II, 0.87 (95% CI, 0.835-0.866) for Grade III, and 0.898 (95% CI, 0.866-0.929) for Grade IV. The Cohen's κ value for intraobserver reliability was 0.891 (95% CI, 0.857-0.925). Conclusions: The adapted classification system shows high interobserver and intraobserver reliabilities for grading of complications when applied to orthopaedic surgery looking at complications of hip preservation surgery. This grading scheme may facilitate standardization of complication reporting and make outcome studies more comparable. © 2012 The Association of Bone and Joint Surgeons®.


Mast N.H.,AONA Martin Allgower Fellowship | Impellizzeri F.,Schulthess Klinik | Keller S.,Schulthess Klinik | Leunig M.,Schulthess Clinic
Clinical Orthopaedics and Related Research | Year: 2011

Background: Several mechanical derangements reportedly contribute to the development of noninflammatory arthritis of the hip. Diagnosis of these derangements involves the use of specific radiographic measures (eg, alpha angle, lateral center edge angle, cross-over sign). The reliability of some of these measures is not known, whereas others have not been confirmed. Questions/purposes: We examined the reproducibility of 20 radiographic parameters of the hip used in clinical practice. Methods: Twenty radiographic parameters on standardized digital AP and cross-table lateral radiographs were evaluated by two observers on two different occasions. The parameters were evaluated from the standpoint of reproducibility (reliability and agreement). The intraclass correlation coefficient (ICC), kappa coefficient, and standard error of measurement were calculated. The minimal detectable change was calculated where possible. Results: Interrater reliability ranged from 0.45 to 0.90 for ICC depending on the measure. Intrarater reliability ranged from 0.55 to 0.99. Measurements that could be measured directly (femoral head diameter) were more reliable than measurements requiring estimation on the part of the observer (Tönnis angle, neck-shaft angle). Categorical parameters had interrater and intrarater reliability kappa values greater than 0.90 for all parameters measured. Agreement between repeated measurements, as given by the minimal detectable change, showed many parameters with low absolute reliability have clinical use in the context of the large changes seen in clinical practice. Conclusion: Radiographic hip measures show clinical utility when evaluated from the perspective of agreement and reliability. Clinical Relevance: All measures investigated show clinical utility when evaluated from the perspective of reliability and agreement. Level of Evidence: Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence. © 2010 The Association of Bone and Joint Surgeons®.


Research has shown common etiopathogenetic mechanisms between somatoform pain disorder, fibromyalgia and chronic fatigue syndrome. Based on reproducible research results the following have been demonstrated: imbalance of the autonomic nervous system with enhanced tonus of the sympathetic nervous system that can be detected early in life, disorders of central sensitization as a basis for chronic pain and evidence that psychopathological disorders play an important role, which require detailed analysis. In addition, neuroticism as a personality trait considerably influences symptom perception and coping with complaints eventually leading to functional disability. Similar etiopathogenetic mechanisms may play an important role in other somatoform disorders. A detailed analysis of individual cases on the basis of the comprehensive information is mandatory with respect to therapeutic actions and assessment of functional ability. The phenomenological similarities between syndromes discussed here can be explained by common pathophysiological mechanisms. The research results indicate possible relevant interference with the functioning ability of individuals who suffer from such disorders. © 2016, Springer-Verlag Berlin Heidelberg.


Surgical objective. Augmentation of the rotator cuff with an ECM patch during arthroscopic rotator cuff repair is performed in order to unload the reconstruction and to activatebiological healing.Indications. Reconstructable rotator cuff ruptures with reduced tendon quality.Contraindications. Non-reconstructable tendon defects.Surgical technique. After tendon reconstruction the graft is shuttled and fixed on the cuff with two medially placed pulling sutures. With two lateral sutures the graft is pulled laterally over the reconstructed cuff and on the lateral tuberculum majus.Aftercare. Immobilization in an abduction pillow for 6 weeks with passive motion, active motion the next 6 weeks, and weight bearing after 12 weeks.Results. Eight patients with a reconstructable re-rupture were augmented with an ECM patch. Short-term results after 6 months showed 5 (62.5%) healed tendons, 1 complete (12.5%) and 2 incomplete re-ruptures (25%). The CS (Constant Score) and SSV (Subjective Shoulder Value) were improved from 51 to 57% and 51 to 71%, which was not significant (p>0.05). The Oxford shoulder score improved significantly from 21 to 38 (p<0.05). There were no relevant intra- or postoperative complications. © Springer-Verlag Berlin Heidelberg 2012.


Hambly K.,University of Kent | Silvers H.J.,Santa Monica Sports Research Foundation | Steinwachs M.,Schulthess Klinik
Cartilage | Year: 2012

Background: Participation in football can put both male and female players at an increased risk for knee osteoarthritis. There is a higher prevalence of focal chondral defects in the knee of athletes compared to nonathletes. The management of chondral defects in the football player is complex and multifactorial. Objective: The aim of this study is to provide an overview of the current strategies for rehabilitation after articular cartilage repair of the knee in the football player. Design: A review of current literature and the scientific evidence for rehabilitation after articular cartilage repair of the knee. Conclusions: Articular cartilage repair has been shown to allow return to sport but rehabilitation timescales are lengthy. Successful rehabilitation for a return to football after articular cartilage repair of the knee requires the player to be able to accept the load of the sport. This necessitates a multidisciplinary approach to rehabilitation, especially in the transition from therapy to performance care. It should be recognized that not all players will return to football after articular cartilage repair. The evidence base for rehabilitative practice after articular cartilage repair is increasing but remains sparse in areas. © SAGE Publications 2012.


Background: Although reconstruction methods have improved, tendon retears remain a major complication associated with rotator cuff repair. With the application of patches, either by interposition or by augmentation, surgeons can attempt to close an irreparable cuff defect or improve the mechanical and biological properties of tendons respectively. Objectives: Which factors need to be considered when using a patch and what outcome can be expected? Materials and methods: Based on the current literature, an overview of the techniques and materials in use and biomechanical and clinical experience is provided. Results: The literature shows clear improvements in the biomechanical properties of a repair with patch augmentation; in particular, weakened tendons of the anterior supraspinatus and superior infraspinatus benefit most. It is important to keep in mind that each patch material has its own individual properties, which makes comparison of the various patch types difficult. The current scientific evidence is promising, although larger level 1 studies are still required. Conclusions: The general use of patches cannot be recommended at this time. Nevertheless, the use of a patch should be considered in patients who are at a high risk of recurrent retears. In future, patches will probably be applied mainly as part of a combined effort, together with biological measures to further reduce retear rates. © 2015, Springer-Verlag Berlin Heidelberg.


Huber M.,Schulthess Klinik
Foot and Ankle Clinics | Year: 2013

Cavovarus deformity results from an imbalance of the foot's extrinsic musculature. Conditions leading to weakness of an isolated muscle result from nerve injury or sequelae of a compartment syndrome. When weakness of a muscle group presents, an underlying neurologic disorder must be suspected. Patients with hereditary sensory motor neuropathy present with a progressive pattern of imbalance and deformity. The deformity starts out flexible but becomes rigid over time. Rebalance muscle pull to realign the foot and ankle is important. Osteotomies and arthrodesis to realign the hindfoot will not maintain alignment as long as the agonist-antagonist pattern is not re-established. © 2013 Elsevier Inc.

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