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Dive into the research topics where Gerardo Juan Maquieira is active.

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Featured researches published by Gerardo Juan Maquieira.


Journal of Bone and Joint Surgery, American Volume | 2006

Latissimus dorsi transfer for the treatment of irreparable rotator cuff tears.

Christian Gerber; Gerardo Juan Maquieira; Norman Espinosa

BACKGROUND Treatment of irreparable rotator cuff tears remains controversial. Latissimus dorsi transfer to the greater tuberosity has been proposed for the treatment of irreparable tears associated with severe functional impairment and chronic, disabling pain. METHODS Sixty-seven patients with sixty-nine irreparable, full-thickness tears of at least two complete tendons were managed with latissimus dorsi transfer and were reviewed clinically and radiographically after an average of fifty-three months. The study group included fifty-two men and fifteen women, with an average age of sixty-one years. Thirteen patients also had deficient subscapularis function preoperatively. Outcome measures included the Constant and Murley score and the Subjective Shoulder Value. Osteoarthritis and acromiohumeral distance were measured on standardized radiographs. RESULTS The mean Subjective Shoulder Value increased from 28% preoperatively to 66% at the time of follow-up (p < 0.0001). The mean age and gender-matched Constant and Murley score improved from 55% to 73% (p < 0.0001). The pain score improved from 6 to 12 points (of a possible 15 points) (p < 0.0001). Flexion increased from 104 degrees to 123 degrees , abduction increased from 101 degrees to 119 degrees , and external rotation increased from 22 degrees to 29 degrees (p < 0.05). Abduction strength increased from 0.9 to 1.8 kg (p < 0.0001). There was a slight but significant increase in osteoarthritic changes (from stage 0.8 to stage 1.3; p = 0.0002). In shoulders with a negative preoperative lift-off test, significant improvements were observed in terms of both function and pain, and strength doubled from 1.0 to 2.0 kg (p = 0.0001), but osteoarthritic changes progressed from stage 0.7 to stage 1.1 (p = 0.0006). In shoulders with poor subscapularis function, no improvement in these parameters was observed. CONCLUSIONS Latissimus dorsi transfer durably and substantially improves chronically painful, dysfunctional shoulders with irreparable rotator cuff tears, especially if the subscapularis is intact. If subscapularis function is deficient, the procedure is of questionable benefit and probably should not be used.


Skeletal Radiology | 2010

Therapeutic impact of [18F]fluoride positron-emission tomography/computed tomography on patients with unclear foot pain

Dorothee R. Fischer; Gerardo Juan Maquieira; Norman Espinosa; Marco Zanetti; Rolf Hesselmann; Anass Johayem; Thomas F. Hany; Gustav K. von Schulthess; Klaus Strobel

PurposeTo evaluate the therapeutic impact of [18F]fluoride positron-emission tomography/computed tomography ([18F]fluoride PET/CT) imaging on patients with unclear foot pain.MethodsTwenty-eight patients were prospectively included in this study. Therapeutic management was defined by two experienced dedicated foot surgeons before and after [18F]fluoride PET/CT imaging. Twenty-six patients underwent cross-sectional imaging [CT, magnetic resonance (MR)] prior to PET/CT. A retrospective analysis of the magnetic resonance imaging (MRI) diagnoses was performed when a therapy change occurred after PET/CT imaging.ResultsIn 13/28 (46%) patients therapeutic management was changed due to PET/CT results. Management changes occurred in patients with the following diagnoses: os trigonum syndrome; sinus tarsi syndrome; os tibiale externum syndrome; osteoarthritis of several joints; non-consolidated fragments; calcaneo-navicular coalition; plantar fasciitis; insertional tendinopathy; suggestion of periostitis; neoarticulations between metatarsal bones. Os trigonum, os tibiale externum, subtalar osteoarthritis and plantar fasciitis were only seen to be active on PET/CT images but not on MR images.Conclusion[18F]fluoride PET/CT has a substantial therapeutic impact on management in patients with unclear foot pain.


Foot & Ankle International | 2015

Natural history of nonoperatively treated osteochondral lesions of the talus.

Georg Klammer; Gerardo Juan Maquieira; Silke Spahn; Vanessa Vigfusson; Marco Zanetti; Norman Espinosa

Background: We hypothesized that patients undergoing nonoperative treatment for asymptomatic or minimally symptomatic osteochondral lesions of the talus (OLTs) would not deteriorate clinically or radiologically over time. Methods: Forty-eight patients (mean age = 48 years; range, 13-78 years) with an OLT confirmed by magnetic resonance imaging (MRI) who had not undergone ankle joint surgery were retrospectively reviewed. All patients were evaluated after a minimum follow-up of 2 years (mean = 52 months; range, 27-124 months). All patients filled out an individual questionnaire and underwent a physical and radiographic assessment (radiograph and hindfoot MRI). Results: At final follow-up, 43 ankles (86%) in 41 patients were pain-free (visual analogue scale [VAS] 0, n = 12) or less painful (VAS 1-3, n = 31). Radiographically, osteoarthritis was absent in 47%, and grade 1 and 2 osteoarthritis each were found in 27% (van Dijk classification). Magnetic resonance imaging revealed no substantial progression in staging or lesion size. Pain at time of follow-up correlated with the depth of the lesion at initial MRI (P < .05) and with subchondral cyst formation and presence or change of bone marrow edema at follow-up MRI (P < .05). Conclusion: Minimally symptomatic OLTs did not appear to progress or worsen over time when treated nonoperatively. Level of Evidence: Level IV, case series.


Foot & Ankle International | 2010

Radiographic Analysis of Metatarsus Primus Elevatus and Hallux Rigidus

Samy Bouaicha; Christine Ehrmann; Beat K. Moor; Gerardo Juan Maquieira; Norman Espinosa

Background: Controversy exists about the role of metatarsus primus elevatus (MPE) in the presence of hallux rigidus. Previous studies could neither confirm nor reject a causative relationship. Measurement of the true elevation of the first metatarsal according to current techniques lack either precision or accuracy or both. The purpose of this study was to assess MPE by means of a new radiographic measurement method and to analyze how the MPE-values differed among hallux rigidus, hallux valgus and control groups. Materials and Methods: A retrospective study was performed of standing AP and lateral radiographs of 295 feet (221 patients; average age 54 years) randomly selected from our databank. According to general radiographic and clinical criteria, 99 were defined as hallux rigidus. Ninety-nine feet had a hallux valgus deformity without severe arthritis. Ninety-seven radiographs with normal MP-I joints and no other forefoot deformity served as a control group. The elevation of the first metatarsal bone in relation to the second metatarsal (MPE), the first metatarsopahlangeal dorsiflexion angle (DFA), the hallux valgus angle (HVA), the intermetatarsal angle (IMA), the interphalangeal angle (IPA) and the degeneration of the first metatarsophalangeal joint were measured. Three independent raters were involved to assess the inter-rater reliability of a new MPE measurement method. For statistic analyses, ANOVA testing was used. Results: MPE was significantly greater in patients with hallux rigidus (+5.2 mm; 95% CI: 4.7 to 5.7) when compared with hallux valgus (+2.8 mm; 95% CI: 2.2 to 3.4) or the control group (+2.6; 95% CI: 2.0–3.2; p < 0.0001). The DFA was found to be significantly lower in the hallux rigidus group (9 degrees; 95% CI: 8 to 10) when compared with those measured in the hallux valgus (14 degrees; 95% CI: 13 to 16) and control groups (11 degrees; 95% CI: 10 to 12; p < 0.0001). There was a no correlation found between MPE and osteoarthritis at MP-I joint (r = 0.35; p < 0.0001). A moderate correlation was found between increasing MPE and decreasing DFA (r = 0.5; p < 0.0001). The inter-rater reliability of the MPE measurement method was found to be accurate and reproducible (r = 0.9; p < 0.0001). Conclusion: Based on the findings in this study, an MPE greater than 5 mm could be considered a predictive factor in the presence of hallux rigidus. However, the mechanism of MPE has yet to be determined. Level of Evidence: III, Case Control Series


Clinical Biomechanics | 2010

Biomechanical consequences of first metatarsal osteotomy in treating hallux valgus

Philippe Favre; M. Farine; Jess G. Snedeker; Gerardo Juan Maquieira; Norman Espinosa

BACKGROUND Among the numerous osteotomies for correction of hallux valgus, the modified chevron is known for its good intrinsic stability and the scarf for its large corrective potential. An intermediate design, the reversed-L osteotomy, has been developed to combine these competing biomechanical objectives. The purpose of this in vitro study was to compare the structural and local biomechanical performance of these three designs. METHODS Stiffness, cortical bone strains (a factor relevant to bone remodeling), strength and failure mode of the scarf, modified chevron and reversed-L osteotomies were measured on human specimens in two different loading configurations. FINDINGS The scarf osteotomy caused significant changes in stiffness and cortical bone strains with the proximal apex being at the origin of bone failure. The chevron and reversed-L had a generally comparable response to the intact bone. The chevron specimens failed by pivoting of the distal fragment, and the reversed-L by pivoting or fracture. INTERPRETATION This is the first study to investigate the cortical bone strain changes induced by these invasive osteotomies. Alterations from the intact bone response could be directly related to the design of the osteotomy. Notably, the critical weakening proximal apex of the scarf is avoided in the reversed-L, leading to results comparable to the chevron. This study provides support in favor of the intermediate design of the reversed-L as an effective compromise between the competing biomechanical objectives of corrective potential and mechanical stability.


Radiology | 2010

Morton Neuroma: MR Imaging after Resection—Postoperative MR and Histologic Findings in Asymptomatic and Symptomatic Intermetatarsal Spaces

Norman Espinosa; Juergen Wilfried Schmitt; Nadja Saupe; Gerardo Juan Maquieira; Beata Bode; Patrick Vienne; Marco Zanetti

PURPOSE To evaluate the prevalence of postoperative magnetic resonance (MR) imaging findings in asymptomatic and symptomatic patients after resection of Morton neuroma. MATERIALS AND METHODS This study was approved by the institutional review board. Informed consent was obtained from each participant. Fifty-eight consecutive patients (46 women, 12 men) who had undergone resection of a painful Morton neuroma (90 Morton neuromas were removed in 66 feet), pre- and postoperative MR imaging, and clinical follow-up for a minimum of 2 years after surgery were identified. Two experienced musculoskeletal radiologists evaluated MR images with regard to the presence of presumed recurrent Morton neuroma, scar, or intermetatarsal bursitis. The prevalence of abnormalities in asymptomatic and symptomatic intermetatarsal spaces was determined. The results of the second radiologist were used only to determine interobserver reliability. The kappa statistics were obtained to assess interobserver agreement. Seven patients with presumed recurrent Morton neuroma underwent repeat surgery. RESULTS Clinically speaking, 68 intermetatarsal spaces (44 of 58 patients [76%], 47 feet) were asymptomatic at follow-up and 22 (14 of 58 patients [24%], 19 feet) were symptomatic. A presumed Morton neuroma was found in 18 (26%) of the asymptomatic spaces and 11 (50%) of the symptomatic spaces. A presumed scar was found in six (9%) of the asymptomatic spaces and two (9%) of the symptomatic spaces. A presumed intermetatarsal bursitis was found in six (9%) of the asymptomatic spaces and six (27%) of the symptomatic spaces. Interobserver agreement for presumed recurrent Morton neuroma was substantial (kappa = 0.64). Histologic examination of presumed recurrent Morton neuroma revealed fibrous tissue but no sign of peripheral neural tissue. CONCLUSION MR imaging after Morton neuroma resection commonly reveals Morton neuroma-like abnormalities in asymptomatic and symptomatic intermetatarsal spaces.


Foot & Ankle International | 2009

Technique Tip: Percutaneous Chrisman-Snook Lateral Ankle Ligament Reconstruction:

Gerardo Juan Maquieira; Beat Kaspar Moor; Norman Espinosa

Level of Evidence: V, Expert Opinion


Journal of Shoulder and Elbow Surgery | 2007

Suprascapular nerve palsy after the Latarjet procedure

Gerardo Juan Maquieira; Christian Gerber; Alberto G. Schneeberger


Revue De Chirurgie Orthopedique Et Reparatrice De L Appareil Moteur | 2004

Transfert du grand dorsal pour le traitement des ruptures massives de la coiffe des rotateurs : quels facteurs déterminent le résultat final ?

Christian Gerber; Gerardo Juan Maquieira; Norman Espinosa


Techniques in Foot & Ankle Surgery | 2008

Salvage arthrodesis after failed total ankle replacement: reconstruction with structural allograft and intramedullary nail

Beat K. Moor; Georg Klammer; Gerardo Juan Maquieira; Norman Espinosa

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