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Dive into the research topics where Dirk Maier is active.

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Featured researches published by Dirk Maier.


Arthritis & Rheumatism | 2009

Prognostic factors in nonoperative therapy for chronic symptomatic calcific tendinitis of the shoulder

P. Ogon; Norbert P. Suedkamp; Martin Jaeger; Kaywan Izadpanah; Wolfgang Koestler; Dirk Maier

OBJECTIVE To define prognostic factors in chronically symptomatic patients with calcific tendinitis of the shoulder. METHODS We evaluated 420 patients (488 shoulders) in the context of a prospective cohort study. Epidemiologic data were assessed. The radiographic and sonographic appearance of the calcific deposits was classified. The mean period of nonoperative therapy was 4.4 years (range 0.5-13.7 years). After referral to our institution, standardized nonoperative therapy was continued for a minimum of 3 months. Failure of nonoperative therapy was defined as the persistence of symptomatic calcific tendinitis of the shoulder after a minimum of 6 months. Prognostic factors (determined at P < 0.05 by chi-square test) were analyzed by logistic regression. RESULTS Of the 420 patients, 269 (64%) were women, 151 (36%) were men. The mean age of the patients was 51.3 years (range 28-84 years). Occurrence of calcific tendinitis of the shoulder was unilateral in 84% and bilateral in 16%. Gärtner type I calcific deposits were found in 37%, type II in 32%, and type III in 31%. Failure of nonoperative therapy was observed in 114 patients (27%). Negative prognostic factors were bilateral occurrence of calcific tendinitis of the shoulder, localization to the anterior portion of the acromion, medial (subacromial) extension, and high volume of the calcific deposit. Positive prognostic factors were a Gärtner type III deposit and a lack of sonographic sound extinction of the calcific deposit. CONCLUSION Our findings demonstrate the existence of prognostic factors in the nonoperative treatment of chronic symptomatic calcific tendinitis of the shoulder. Guidelines for optimal treatment can be implemented according to these factors to avoid a long-term symptomatic disease course.


Journal of Bone and Joint Surgery, American Volume | 2014

Proximal Humeral Fracture Treatment in Adults

Dirk Maier; Martin Jaeger; Kaywan Izadpanah; Peter C. Strohm; Norbert P. Suedkamp

Most proximal humeral fractures affect elderly patients and can be treated nonoperatively with good functional outcomes.The treatment of displaced three and four-part fractures remains controversial and depends on a variety of underlying factors related to the patient (e.g., comorbidity, functional demand), the fracture (e.g., osteoporosis), and the surgeon (e.g., experience).Throughout the literature, open reduction and locking plate osteosynthesis is associated with considerable complication rates, particularly in the presence of osteoporosis.Low local bone mineral density, humeral head ischemia, residual varus displacement, insufficient restoration of the medial column, and nonanatomic reduction promote failure of fixation and impair functional outcome.The outcome of hemiarthroplasty is closely related to tuberosity healing in an anatomic position to enable the restoration of rotator cuff function. Reverse shoulder arthroplasty may provide satisfactory shoulder function in geriatric patients with preexisting rotator cuff dysfunction or after the failure of first-line treatment.


Journal of Bone and Joint Surgery, American Volume | 2007

Stabilization of the long head of the biceps tendon in the context of early repair of traumatic subscapularis tendon tears.

Dirk Maier; Martin Jaeger; Norbert P. Suedkamp; Wolfgang Koestler

BACKGROUND Tears of the subscapularis tendon commonly are associated with instability of the long head of the biceps tendon. Standard surgical treatment includes tenodesis or tenotomy of the biceps tendon. However, chronic discomfort from spasms and cosmetic disadvantages have been reported following both procedures, while the potential for functional impairments remains controversial. We investigated the outcome of stabilization of the long head of the biceps tendon in the context of early repair of traumatic tears of the subscapularis tendon. METHODS We performed stabilization of an unstable, structurally intact long head of the biceps tendon in twenty-one patients in the acute phase after a traumatic tear of the subscapularis tendon. The average period from the injury to the surgery was 6.2 weeks. Open tendon stabilization and subscapularis reconstruction were performed with transosseous sutures. The follow-up consisted of clinical examination (with determination of the absolute, age and gender-related, and individual relative Constant scores; clinical evaluation of the long head of the biceps; and subjective determination of shoulder function) and dynamic ultrasound examination. RESULTS The average follow-up period was 28.4 months. The mean absolute Constant score increased from 26.3 points preoperatively to 79.3 points postoperatively (p < 0.01). The mean age and gender-related Constant score improved from 28.0% to 87.0% (p < 0.01). Seven patients showed clinical symptoms consistent with mild biceps tendinopathy. Using dynamic ultrasound examination, we found two cases of recurrent instability (medial subluxation) of the long head of the biceps tendon. Secondary rupture of the long head of the biceps tendon occurred in one patient, twenty-six months after the surgery. CONCLUSIONS The functional outcomes of stabilization of the long head of the biceps tendon in the context of early repair of a traumatic tear of the subscapularis tendon were comparable with the results of tenodesis or tenotomy reported in previous studies. The cosmetic results were superior, and chronic discomfort from spasms was not observed. Stabilization of the tendon of the long head of the biceps can be recommended as a treatment option for selected patients and should be discussed as an alternative to tenodesis or tenotomy, particularly in a young patient.


Arthroscopy | 2013

Rotator Cuff Preservation in Arthroscopic Treatment of Calcific Tendinitis

Dirk Maier; Martin Jaeger; Kaywan Izadpanah; Lutz Bornebusch; Norbert P. Suedkamp; Peter Ogon

PURPOSE We sought to evaluate (1) clinical and radiologic results after arthroscopic calcific deposit (CD) removal and (2) the relevance of remnant calcifications (RCs). METHODS The study included 102 patients undergoing arthroscopic CD removal, preserving integrity of the rotator cuff. Postoperatively, we divided patients into 2 groups according to the extent of CD removal achieved. Group 1 consisted of patients with complete CD removal. Group 2 included patients showing minor RCs. Ninety-three patients (99 shoulders) completed follow-up. The mean patient age was 50.6 years (31 to 68 years), and the mean follow-up period was 37.3 months (24 to 83 months). We obtained anteroposterior (AP) and outlet radiographs before surgery, postoperatively, and at follow-up. We used the absolute and age- and sex-related Constant scores (CSabs, CSrel) as outcome measures. We compared both groups statistically (Mann-Whitney U test; P < .05). RESULTS Complete CD removal was achieved in 82 of 99 (82.8%) shoulders (group 1). Postoperatively, minor RCs were found in 17 of 99 (17.2%) shoulders (group 2), an average of 58.6% (± 26.2) of the mean preoperative size. All RCs showed complete (14 of 17) or virtually complete (3 of 17) resolution at follow-up. Overall mean CSabs and CSrel were 88.8 points (± 10.4) and 99.0% (± 3.7), respectively. Mean values of CSabs and CSrel in group 1 (89.5 points ± 9.5 and 99.1% ± 3.7, respectively) and group 2 (86.1 points ± 12.9 and 98.7% ± 4.2, respectively) did not differ. CONCLUSIONS Arthroscopic CD removal, preserving integrity of the rotator cuff yielded good to excellent results in 90% of patients and avoided iatrogenic tendon defects in all patients. Minor RCs did not impair clinical outcome and spontaneously resolved at follow-up. LEVEL OF EVIDENCE Level IV, therapeutic case series.


American Journal of Sports Medicine | 2012

In Vivo Analysis of Coracoclavicular Ligament Kinematics During Shoulder Abduction

Kaywan Izadpanah; Elizabeth Weitzel; Matthias Honal; Jan Thorsten Winterer; Marco Vicari; Dirk Maier; Martin Jaeger; Elmar Kotter; Jürgen Hennig; Matthias Weigel; Norbert P. Südkamp

Background: Anatomic reconstruction of the coracoclavicular ligaments for the treatment of acromioclavicular joint separations provides superior biomechanical stability compared with other procedures. Clavicular and coracoidal footprints of the conoid ligament (CL) and the trapezoid ligament (TL) are well described. So far, little is known about their kinematics and the changes of the coracoclavicular distance during shoulder abduction. Hypothesis: The coracoclavicular distance along the coracoclavicular ligaments changes significantly with shoulder abduction and weightbearing. Study Design: Descriptive laboratory study. Methods: With use of an open magnetic resonance imaging scanner, the shoulders of 13 healthy volunteers were examined in supine and sitting positions. Three-dimensional magnetic resonance images of the shoulders were obtained in 30° increments of abduction (0°-120°). A manual segmentation of the scapula, the clavicle, and the coracoclavicular ligaments was performed. The insertion points of the coracoclavicular ligaments were identified, and automated measures along the ligamentous course were carried out. Results: During transfer from the lying to sitting position, the coracoclavicular distance showed significant lengthening of 3 mm along the center of the CL, which significantly increased another 3 mm during shoulder abduction to a total lengthening of 6 mm. In the supine position, the coracoclavicular distance along the TL did not elongate significantly. In the sitting position, the distance along the medial portion of the TL shortened significantly, whereas the distance along the center portion did not elongate significantly during shoulder abduction. Conclusion: The distances between the coracoclavicular insertion points depend on both patient and shoulder positioning. To prevent overconstraining of the graft, the CL should be fixated during 90° to 120° of shoulder abduction in a sitting position. Isometric reconstruction of the TL can be achieved if precise fixation of the graft at the centers of the conoidal and clavicular footprints is performed.


Journal of Magnetic Resonance Imaging | 2013

A stress MRI of the shoulder for evaluation of ligamentous stabilizers in acute and chronic acromioclavicular joint instabilities

Kaywan Izadpanah; J. Winterer; Marco Vicari; Martin Jaeger; Dirk Maier; Leonie Eisebraun; Jutta Ute Will; E Kotter; Mathias Langer; Norbert P. Südkamp; Jürgen Hennig; Mathias Weigel

To show the feasibility of a stress magnetic resonance imaging (MRI) as a new method for simultaneous evaluation of the morphology and the functional integrity of the acromioclavicular joint (ACJ) ligamentous stabilizers.


Chirurg | 2012

Frakturen des Humeruskopfes

Martin Jaeger; Kaywan Izadpanah; Dirk Maier; K. Reising; Strohm Pc; Norbert P. Südkamp

Fractures of the proximal humerus are commonly seen especially in the elderly population. High-energy trauma in young people can be distinguished from low-energy trauma in the elderly resulting from falls of a low height which are typically characterized by osteoporosis. A precise analysis of fractures is essential for a good understanding of the fracture and an individual therapy for which the LEGO-Codman classification provided by Hertel is recommended. Nonsurgical therapy is commonly performed and widely accepted not only for simple fractures. For osteosynthesis angular stable implants became the gold standard but are frequently associated with a high rate of complications some of which can be lowered by an improved surgical technique. Even today varus dislocated fractures are challenging, especially in combination with destruction of the medial column. In those cases where stable osteosynthesis can no longer be achieved arthroplasty is indicated. The clinical results of anatomic fracture arthroplasty are strongly related with correct ingrowth of the tuberosities. Reverse fracture arthroplasty may be considered but indications should be interpreted with caution and preferably used in patients older than 75 years.


Chirurg | 2012

Fractures of the humerus head

Martin Jaeger; Kaywan Izadpanah; Dirk Maier; K. Reising; Strohm Pc; Norbert P. Südkamp

Fractures of the proximal humerus are commonly seen especially in the elderly population. High-energy trauma in young people can be distinguished from low-energy trauma in the elderly resulting from falls of a low height which are typically characterized by osteoporosis. A precise analysis of fractures is essential for a good understanding of the fracture and an individual therapy for which the LEGO-Codman classification provided by Hertel is recommended. Nonsurgical therapy is commonly performed and widely accepted not only for simple fractures. For osteosynthesis angular stable implants became the gold standard but are frequently associated with a high rate of complications some of which can be lowered by an improved surgical technique. Even today varus dislocated fractures are challenging, especially in combination with destruction of the medial column. In those cases where stable osteosynthesis can no longer be achieved arthroplasty is indicated. The clinical results of anatomic fracture arthroplasty are strongly related with correct ingrowth of the tuberosities. Reverse fracture arthroplasty may be considered but indications should be interpreted with caution and preferably used in patients older than 75 years.


Knee Surgery, Sports Traumatology, Arthroscopy | 2018

Sport-specific outcomes after isolated meniscal repair: a systematic review

Helge Eberbach; Jörn Zwingmann; Lisa Hohloch; Gerrit Bode; Dirk Maier; Philipp Niemeyer; Norbert P. Südkamp; Matthias J. Feucht

PurposeThe purpose of this systematic review was to assess sport-specific outcomes after repair of isolated meniscal tears.MethodsA systematic electronic search of the MEDLINE and Cochrane database was performed in May 2016 to identify studies that reported sport-specific outcomes after isolated meniscal repair. Included studies were abstracted regarding study characteristics, patient demographics, surgical technique, rehabilitation, and outcome measures. The methodological quality of the included studies was assessed with the Coleman Methodology Score (CMS).ResultsTwenty-eight studies with a total of 664 patients met the inclusion criteria. The methodological quality of the included studies was moderate, with a mean CMS of 69.7 ± 8.3. The mean patient age was 26 ± 7.2 years and 71% of patients were male. Mean preoperative Tegner score improved from 3.5 ± 0.3 to 6.2 ± 0.8 postoperatively. Comparing preinjury and postoperative Tegner scores, comparable values were observed (6.3 ± 1.1 and 5.7 ± 0.8, respectively). Return to sports on the preinjury level was achieved in 89%. Mixed-level populations returned to their preinjury activity level in 90% and professional athletes in 86%. Mean delay of return to sports varied between 4.3 and 6.5 months, with comparable results between professional and mixed-level athletes. The pooled failure rate was 21%. The failure rate was lower in professional athletes compared to mixed-level athletes (9% vs. 22%).ConclusionThis systematic review suggests that isolated repair of meniscal tears results in good to excellent sport-specific outcomes and a high return to sports rate in both recreational and professional athletes. The failure rate is comparable to systematic reviews not focusing on sportive patients.Level of evidenceLevel IV systematic review of Level I to Level IV studies.


Cartilage | 2017

Osteoarthritis in Football With a Special Focus on Knee Joint Degeneration

Gian M. Salzmann; Stefan Preiss; Marcy Zenobi-Wong; Laurent P. Harder; Dirk Maier; Jirí Dvorák

Football is currently the most popular sporting activity in the world. Multiple reports have shown that a high incidence of osteoarthritis is found in football players. Evidence clearly shows that traumatic injury significantly predisposes players for such pathophysiology. Injuries are frequent in amateur as well as professional football players, with knee and ankle accounting for the most severe injuries. Many professional athletes lose playing time due to injuries and many are forced into early retirement. Posttraumatic osteoarthritis is a common finding among ex-football players with numbers well above the normal population. Today’s surgical techniques are advanced and capable of restoring the joint to a certain extent. However, a restitution ad integrum is reached only in very rare cases. Professional football players that return to play after serious injuries perform their extremely strenuous activity on morphologically compromised joints. Incomplete rehabilitation and pressure to return to play after an injurious event clearly put the athlete at an even higher risk for joint degeneration. Prevention strategies, improved surgical management, strict rehabilitation, as well as future aspects such as early suppression of inflammation, personalized medicine, and predictive genomics DNA profiling are needed to reduce incidence and improve the health perspectives of football players.

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Peter Ogon

University of Freiburg

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Strohm Pc

University of Freiburg

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Gernot Lang

University of Freiburg

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Lutz Bornebusch

University Medical Center Freiburg

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