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Biologia del callo osseo
No full textLe conoscenze riguardo il processo della riparazione delle fratture nell’ uomo sono molto progredite negli ultimi anni, soprattutto grazie al miglioramento delle tecniche di indagine. Sebbene infatti la morfologia delle
varie fasi della ricostruzione ossea post-fratturativa sia da tempo ben conosciuta (Aho, 1966; Bier, 1918; Brighton, 1991; Einhorn, 1998; Gumbel,
1906; Ham, 1972; Henricson, 1987; McLean, 1955 e 1968; McKibbin,
1978; Postacchini, 1991 e 1995; Probst, 1997; Tang, 1982; Urist, 1943 e
1951), i meccanismi che ne guidano l'evoluzione sono lungi dall'essere del
tutto compresi. Infalti, mentre dal punto di vista teleologico alle varie fasi e
attribuibile un chiaro significato, i segnali che ne determinano l'avvicendarsi globale e focale, sono talmente complessi che necessitano ulteriori studi.
Per altro l’aumento della durata della vita media accompagnato alia maggiore sopravvivenza dei soggetti con malattia neoplastica, che hanno aumentato il tasso di fratture patologiche da una parte, e le tecniche di allungamento per distrazione, sempre più in uso, sia per patologie congenite che
acquisite, hanno reso sempre più necessario capire i fini meccanismi della
regolazione della produzione del callo di riparazione, al fine di poter incidere su di esso e poterne modulare l'efficienza a tini terapeutici più generalmente intesi.
Scopo di questa relazione 6 quello di puntualizzare lo stato attuale delle conoscenze sulla biologia dei callo osseo, in base a quanto fin'ora presente in
letteratura, non disgiunto dalla personale esperienza degli autori
Operative management of lumbar disc herniation : the evolution of knowledge and surgical techniques in the last century.
No full textRemoval of a herniated disc with the use of the operative microscope was first performed by Yasargil (Adv Neurosurg. 4:81-2, 1977) in 1977. However, it began to be used more and more only in the late 1980s (McCulloch JA (1989) Principles of microsurgery for lumbar disc disease. Raven Press, New York). In the 1990s, many spinal surgeons abandoned conventional discectomy with naked-eye to pass to the routine practice of microdiscectomy. The merits of this technique are that it allows every type of disc herniation to be excised through a short approach to skin, fascia and muscles as well as a limited laminoarthrectomy. For these reasons, it has been, and still is, considered the "gold standard" of surgical treatment for lumbar disc herniation, and the method used by the vast majority of spinal surgeons. In the 1990s, the advent of MRI and the progressive increase in definition of this modality of imaging, as well as histopathologic and immunochemical studies of disc tissue and the analysis of the results of conservative treatments have considerably contributed to the knowledge of the natural evolution of a herniated disc. It was shown that disc herniation may decrease in size or disappear in a few weeks or months. Since the second half of the 1990s there has been a revival of percutaneous procedures. Some of these are similar to the percutaneous automated nucleotomy; other methods are represented by intradiscal injection of a mixture of "oxygen-ozone" (Alexandre A, Buric J, Paradiso R. et al. (2001) Intradiscal injection of oxygen ozone for the treatment of lumbar disc herniations: result at 5 years. 12th World Congress of Neurosurgery; 284-7), or laserdiscectomy performed under CT scan (Menchetti PPM. (2006) Laser Med Sci. 4:25-7). The really emerging procedure is that using an endoscope inserted into the disc through the intervertebral foramen to visualize the herniation and remove it manually using thin pituitary rongeurs, a radiofrequency probe or both (Chiu JC. (2004) Surg Technol Int. 13:276-86). Microdiscectomy is still the standard method of treatment due to its simplicity, low rate of complications and high percentage of satisfactory results, which exceed 90% in the largest series. Endoscopic transforaminal discectomy appears to be a reliable method, able to give similar results to microdiscectomy, provided the surgeon is expert enough in the technique, which implies a long learning curve in order to perform the operation effectively, with no complications. All the non-endoscopic percutaneous procedures now available can be used, but the patient must be clearly informed that while the procedure is simple and rapid, at least for the disc L4-L5 and those above (except for laserdiscectomy under CT, that can be easily performed also at L5-S1), their success rate ranges from 60 to 70% and that, in many cases, pain may decrease slowly and may take even several weeks to disappear. © 2011 Springer-Verlag/Wien
Long-term results of conservative management of midshaft clavicle fracture
Full text linkA series of 91 patients (59 males, 32 females, mean age 41 years) with middle-shaft clavicle fracture were assessed at a mean of 8.7 years after injury. Based on Allman's classification, fractures were placed in group Ia, Ib and Ic. The majority (66%) were allocated to groups Ib or Ic. Clinical evaluation was made using the Constant score and simple shoulder test. On post-injury radiographs, we measured the amount of overlapping of the fracture fragments (OV) both in centimetres and as percentage of the length of the clavicle and the mean distance between cranio-caudally displaced fragments (DS). The mean Constant scores were 87.1% and 85.6% in groups Ib and Ic, respectively. In patients with a Constant score > or =90%, the mean OV was 7.7% and the average DS was 1.59 cm. In those with a Constant score of 81-89% the average OV and DS were 12% and 1.6 cm, respectively, with the greatest OV being 12.9. In the nine patients whose Constant score was > or =80% the mean OV was 13.2 and the average DS was 1.7; however, the majority of patients had an OV > 15% and DS > or = 2 cm. In these nine patients the mean Constant score was significantly lower than that in the group with a score of > or =90%. The simple shoulder test showed that 20% of patients were dissatisfied with the outcome; a low score was associated with a severe degree of OV or DS. Fracture nonunion occurred in five cases (5.5%). We conclude that there is a clear-cut indication for surgery in patients with OV > or = 15% or DS > or = 2.3 cm as well as in those with an OV > or = 13% associated with a DS > or = 2 cm. This holds particularly for young and middle-aged patients
Sediment transport and morphodynamics generated by a dam-break swash uprush: Coupled vs uncoupled modeling
No full textThe present work analyzes the hydro-morphodynamics characterizing the swash region during the uprush stage. A comparison is illustrated between the sediment transport measured in a series of dam-break experiments and that predicted by the numerical hydro-morphodynamic model of Postacchini et al. (2012). The primary aim is to investigate the differences arising between the weakly coupled or uncoupled model and the measurements, in terms of hydrodynamics, tip celerity and sediment transport. The hydrodynamics are well described by the model and results have been used to calibrate both friction factor and subgrid turbulent viscosity. Comparison of numerically-computed tip celerity with experimental data reveals a fairly good agreement, i.e. a mean error of about 10%, while modeled sediment transport differs by about 40% from the available data. No evident differences are found between results obtained from the coupled and uncoupled model runs (2% for the celerity and 11% for the sediment transport rate at the tip), suggesting that for the specific flow under investigation, at the leading edge of the swash front, hydro-morphological coupling is not an issue of fundamental importance. However, for the special case here of a swash forced by a dam-break, scour occurs at the dam location, and in this case the erosion of the bed is significantly larger in the uncoupled model
Long term results of conservative management of midshaft clavicle fracture
No full textPurpose: VariouS treatments have been suggested for midshaft claviclc fractures. WE analyzed a large series of
midshaft clavicle fractures treated conservatively to determine the prevalence of solid union and the causes of
unsatisfactory outcomes.
Material and Methods: We analyzed the clinical charts of 556 patients with clavicle fracture treated at our
Emergency Dept. ftoDn. 1994 to 2001. Fractures were classified using Allnian's system.
Pathological fractures, skeletally immature subjects, polytrauma cases, patients aged >75 and fractures associated
to AC dislocation were excluded. Fractures of the medial and lateral clavicle were also excluded. Of the remaining
121 patients, 30 could not be traced, thus leaving 91 cases {M; 59 ; F: 32 ; mean age 41 ; left side 58%). The mean
F.U was 9.7 years. Shoulder function was assessed with Constant's score (CS). Both shoulders were radiographed
(AP and Zanca's view ; magnification: 9%). Hill's system was used to evaluate clavicle shortening. Subjective
satisfaction was assessed with SST.
Results: The mean CS for Allman's subgroups la, lb, k was 98%, 88%, and 83%, respectively.
Shoulder pain was present only in few patients in Groups lb and Ic. CS was lower in patients with severe initial
fracture displacement and/or clavicle shortening and in those in Group Ic. Nonunion, confirmed by CT, occurred
in 5 cases (5.5%) of Group lb or Ic (atrophic in 3: CS: 84% ; hypertrophic in 2: CS: 81%). In these, initial
shortening was greater than 2 cm. 90% of patients had satisfactory results (SST>10). Reasons for dissatisfaction
included shoulder weakness, pain related to hypertrophic callus and cosmetic defects.
Conclusion: Conservative treatment gives satisfactory results in a high percentage of patients. 90% considered
their funnctional result as satisfactory. Nonunion rate is lower than that found in surgically treated series. Indications
tor surgery- are fractures with > 2 cm clavicle shortening and thin patients of Group Ic
Instabilità anteriore: intervento di Bankart e capsuloplastiche
No full textL’ esperienza dell'ultimo decennio indica che
gran parte delle forme di instabilità della spalla
può essere trattata per via artroscopica con
risultati analoghi a quelli forniti dalla chirurgia
a cielo aperto. Tuttavia, nelle instabilità dovute
a distacchi capsulo-legamentosi dall'omero
(HAGL) o nelle lesioni di Hill-Sachs incarcerate,
la chirurgia aperta rappresenta il trattamento
preferito da molti chirurghi. In altre forme di
instabilità, come quelle associate a fratture del
bordo glenoideo anteriore, la chirurgia aperta
e, invece, il trattamento di elezione, particolar-
mente quando la frattura interessa più di un
quinto dell'intera superficie della glenoide.
La stabilita post-chirurgica della spalla non
deve essere ottenuta al prezzo di una rigidità
articolare. Questa può essere causa di disabilita
e di predisposizione a un'artropatia. le capsuloplastiche a cielo aperto hanno determinato
spesso una perdita di alcuni gradi di extrarotazione. E’ stato proprio questo motivo, oltre a
quello estetico e alia più alta morbilità, che ha
progressivamente indotto i chirurghi di spalla
ad abbandonare il trattamento a cielo aperto di
riparazione della lesione di Bankart e a prediligere quello artroscopico.
Lo scopo di questo lavoro e quello di descrive
re le tecniche di capsuloplastica in voga negli
anni Ottanta e Novanta, e da noi utilizzate,
che sono state nel tempo sostituite da
artroscopiche
Riparazione a cielo aperto.
No full textLa maggior parte delle rotture della cuffia dei rotatori della
spalla possono essere trattate con approccio artroscopico.
Ciò vale particolarmente per le rotture di piccole e medie
dimensioni in soggetti in età adulta o senile con nessuna o
moderata osteoporosi. Nelle rotture di grandi dimensioni
puo essere spesso effettuata la riparazione artroscopica.
Tuttavia, in alcune rotture molto ampie può essere opportune effettuare una riparazione a cielo aperto, fissando i monconi tendinei in una trincea ossea, che da più sicurezza di
tenuta della riparazione con ancore. Ciò vale in particolare
per i pazienti con marcata osteoporosi in cui le ancore possono non avere un'adeguata tenuta.
Nelle rotture irreparabili, in cui 1 monconi tendinei sono
retratti e non avvicinabili in alcun modo alia sede di inserzione e necessaria una riparazione a cielo aperto, effettuando
una trasposizione del grande dorsale o del grande rotondo o
di entrambi
Injury to major abdominal vessels during posterior lumbar interbody fusion. A case report and review of the literature.
No full textACKGROUND CONTEXT: Numerous cases of injury to major abdominal vessels during the excision of a lumbar herniated disc have been reported, but no cases of injury during interbody fusion by a posterior approach have been described.
PURPOSE: To report on an injury to common iliac vessels during a posterior lumbar interbody fusion (PLIF) and discuss the causes and possible preventive measures.
STUDY DESIGN: A unique case report and a review of the literature.
METHODS: The hospital chart and autopsy report of a single patient were analyzed.
RESULTS: A 52-year-old woman with L4-L5 disc degeneration underwent PLIF. During scraping of the vertebral end plates, there was a sudden increase in blood flow from the disc space, however not copious, with no changes of vital parameters. When the patient was placed supine, severe hypotension and abdominal distension led to strongly suspect a lesion to abdominal vessels. At laparotomy, carried out by a vascular surgeon, a vast retroperitoneal hematoma was evacuated and the vascular lesions were repaired. Postoperatively, the patient continued to lose blood from the abdominal drains and after 4 hours, she was reoperated by another vascular surgeon, who found a diffuse hemorrhage from the small vessels in the surgical field. Soon after the surgery the patient died.
CONCLUSIONS: The lesions were produced by a shaver used for scraping the vertebral end plates. The absence of abundant bleeding from the disc space was possibly because of the compression of the iliac vessels by the pads of the frame on which the patient was lying. The causes of the lesions and possible prevention of similar injuries are analyze
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