The anatomy and vascularity of the lunate: considerations applied to Kienböck’s disease

PURPOSE

The purpose of this study was to assess the anatomy and vascularity of the lunate. The genesis of lunatomalacia requires some combination of vascular risk and mechanical predisposition. The findings will be correlated with the major existing theories of the cause of Kienböck's disease.

METHODS

We studied 27 cadaver upper limbs using latex injection and the Spalteholz technique. We investigated the blood supply to the lunate. In 24 wrists we evaluated the incidence and distribution of anatomic features, arthrosis, and soft tissue lesions. We correlated the lunate morphology and ligaments disruptions with the arthritic changes.

RESULTS

The lunate morphology results as classified by Antuña-Zapico were five type I (20.8%), 18 type II (75%) and one type III (4.2%). The lunate was found to have a separate facet for the hamate in 11 cases (45.8%). The most common size of the facet was found to be 3 mm (range, 3-6 mm). Arthrosis was identified with most frequency in the radius (88.2%) and lunate (94.1%). The triangular fibrocartilage complex was found torn in 58.3%, the lunotriquetral interosseous ligament was torn in 20.8% and the scapholunate interosseous ligament (SLIL) was torn in 54.2% of the wrists. There was a correlation between the presence of arthrosis at the hamate and the presence of a lunate facet (P=0.027) and a correlation between the presence of a tear in the SLIL and arthrosis in the scaphoid (P=0.002). The nutrient vessels entered the lunate through the dorsal and volar poles in all the specimens. The dorsal intercarpal and radiocarpal arches supply blood to the lunate from a plexus of vessels located directly over the lunate's dorsal pole. Vessels entered the dorsal aspect of the lunate through one to three foramina. One to five nutrient vessels were observed entering the volar pole through various ligament insertions, including the ligament of Testut-Kuentz (radio-scapho-lunate (RSL) ligament) and the radiolunate triquetrum ligament (or dorsoradial carpal ligament) and ulnar lunate triquetral ligament.

CONCLUSIONS

The lunate had consistent dorsal and palmar arteries entering the bone in all the specimens. The blood supply and foramina number is greater in the volar pole of the lunate than the dorsal pole. The lunate blood supply comes from different ligaments. In the etiopathogeny of Kienböck's disease it is possible that an acute or chronic, traumatic or non-traumatic injury of the vessel bearing ligaments, particularly because of their structure and the location of the RSL ligament, may have an important role in the appearance of lunate necrosis.

Monteggia fractures in adults. Review of 54 cases

INTRODUCTION

We present a review of Monteggia fractures treated in our hospital between 1992 and 1998.

PATIENTS AND METHODS

Fifty four patients with a Monteggia fracture were treated in our hospital with an average follow-up of 24 months (12-48 months). The average age was 41 years (18-81 years). According to the classification of Bado, there were 24 type I, 20 type II, 6 type III and 4 type IV. The etiology was in 27 cases a motor-vehicle and motorcycle accident, five a pedestrian struck by a car, 21 by a causal fall and only one by a direct hit by an iron bar in an assault. In 56% of the patients, the lesions were associated with polytrauma. In all the cases, treatment consisted of open reduction and internal fixation of the ulnar fracture using different methods of osteosynthesis (3.5 mm DCP, 3.5 mm reconstruction plates, 6.5 mm cancellous screw, tension band technique with Kirschner wires, and one-third tubular plates). Initial treatment of the radial head dislocation was attempted by closed reduction and verification under fluoroscopy. Subsequent open reduction and osteosynthesis were performed in 10 cases, and resection of radial head was necessary in three cases as the initial treatment. There were six open fractures with one case developing chronic infection.

RESULTS

Results were evaluated according to the criteria of Anderson (union fracture, elbow and wrist flexion/extension). The results were excellent in nine patients (17%), satisfactory in 33 (61%), unsatisfactory in nine (17%) and failure in three (5%). Complications could be attributed to the severity of injury, type of fixation and errors in technique (four non-union, three failure of one-third tubular plates, one distal radioulnar instability) and to some features peculiar to this lesion (five nerve injuries, three redislocations of the radial head and four radioulnar synostosis). We needed to perform 14 reoperations to resolve some of the above mentioned complications.

The complete normalization of the adrenocortical function as the criterion of cure after transsphenoidal surgery for Cushing's disease

Transsphenoidal microsurgery is the standard treatment for patients with Cushing's disease. However, there is general lack of agreement regarding the definition of cure. We studied 58 patients with corrected hypercortisolism after transsphenoidal surgery for Cushing's disease. Plasma and urinary cortisol levels were measured after surgery. After the postsurgical hypocortisolism stage (or periodically in patients without hypocortisolism), urinary free cortisol, plasma cortisol at 0800 h and 2300 h, morning cortisol after 1 mg dexamethasone, and cortisol response to insulin-induced hypoglycemia were performed. Patients were classified in 3 groups: group I, patients with transient hypocortisolism and normal hypothalamus-pituitary-adrenal axis afterwards; group II, patients with transient hypocortisolism and abnormalities in the circadian rhythm or the stress response afterwards; and group III, patients without postoperative hypocortisolism. Thirty-three patients were included in group I, 8 in group II, and 17 in group III. Groups I and II were similar in postsurgical plasma cortisol (46.9 +/- 30.3 vs. 60.7 +/- 38.6 nM) and mean follow-up (69.8 vs. 68.8 months) but were significantly different in their recurrence rate (3.4% vs. 50%, P < 0.001). Patients in group III had normal postsurgical plasma and urinary cortisol but persistent abnormalities in circadian rhythm and stress response. After a mean follow-up of 39.1 months, their recurrence rate was similar to that of group II (64.7% vs. 50%). The complete normalization of the adrenocortical function, which is always preceded by postsurgical hypocortisolism, is associated with a very low recurrence risk and should be considered, in our opinion, the main criterion of surgical cure in Cushing's disease.

Homogeneous nucleation of NaCl in supersaturated solutions

The seeding method is an approximate approach to investigate nucleation that combines molecular dynamics simulations with classical nucleation theory. Recently, this technique has been successfully implemented in a broad range of nucleation studies. However, its accuracy is subject to the arbitrary choice of the order parameter threshold used to distinguish liquid-like from solid-like molecules. We revisit here the crystallization of NaCl from a supersaturated brine solution and show that consistency between seeding and rigorous methods, like Forward Flux Sampling (from previous work) or spontaneous crystallization (from this work), is achieved by following a mislabelling criterion to select such threshold (i.e. equaling the fraction of the mislabelled particles in the bulk parent and nucleating phases). This work supports the use of seeding to obtain fast and reasonably accurate nucleation rate estimates and the mislabelling criterion as one giving the relevant cluster size for classical nucleation theory in crystallization studies.

Dorsolateral biplane closing radial osteotomy in zero variant cases of Kienböck's disease

Twenty-six patients with Lichtman stages II and III Kienböck's disease had biplane dorsolateral radial closing osteotomy to reduce the radial inclination and dorsal angles on the sagittal plane. The effects of the procedure were studied clinically, radiologically, and by magnetic resonance imaging in a 2- to 6-year follow-up study (average follow-up period, 3.5 years). The signal intensity on T1- and T2-weighted images of the lunate increased after surgery in all patients, suggesting revascularization. The comparative advantages of this technique are discussed with regard to others currently used.

[Attachment process between an infant and his/her mother: the first year]

Attachment theory is focused upon the development of the attachment process organized jointly by the child and the environmental factors which contribute to the development of the feeling of security. The authors focus on the mother-baby relationships and describe the normative process of attachment relationships during the first year of life. The ethologic perspective of this development is also summarized. The steps of the developing attachment relationship are described. The description of motherhood is focused on the bonding process, which is a more immediate and biologically based process and on caregiving which is a symmetrical motivational system as complex as the attachment one. The main factors known as having an impact on the two processes are described.

Rupture of all the flexor tendons in the hand due to malunion of a distal radius fracture

We report the case of a patient in whom the flexor digitorum superficialis and flexor digitorum profundus tendons to the index, middle, ring and little fingers ruptured 6 years following malunion of a distal radius fracture. There was no history of rheumatoid disease. The distal ulna was displaced volarly and perforated the volar wrist capsule. There was a cumulative biological effect from chronic synovitis and mechanical compression due to the ulnar head impinging upon the normal anatomic course of the flexor tendons to the ring and little fingers. We discuss the physiopathology of this rare lesion and postulate that flexor tendon rupture to the index and middle fingers will occur on the volar surface of the radius when there is a malunion with dorsal tilt.

MEN-2A syndrome and pulmonary metastasis

A case of multiple endocrine neoplasia syndrome type-2A (MEN-2A) with primary hyperparathyroidism and medullary carcinoma of thyroid initially treated by surgery is reported. The presence of pulmonary nodules six years after the initial treatment was thought to be related to metastasis of medullary carcinoma, and the increase in serum calcium concentrations was assumed to be caused by persistence of parathyroid adenomatous or hyperplastic tissue. The patient underwent surgery again and the pulmonary nodules were confirmed to be metastases of a parathyroid carcinoma, a very rare entity in MEN-2A syndrome.

Differences in intraoperative and surgical outcomes between normotensive pheochromocytomas and sympathetic paragangliomas (PPGLs) and hypertensive PPGLs: results from the PHEO-RISK STUDY

PURPOSE

To compare the intraoperative and surgical outcomes of normotensive pheochromocytomas and sympathetic paragangliomas (PPGLs), hypertensive PPGLs and non-PPGL adrenal lesions.

METHODS

This a retrospective multicenter cohort study of patients with PPGLs from 18 tertiary hospitals. A control group of histologically confirmed adrenocortical adenomas (non-PPGL group) was selected to compare intraoperative and surgical outcomes with of the normotensive PPGLs.

RESULTS

Two hundred and ninety-six surgeries performed in 289 patients with PPGLs were included. Before surgery, 209 patients were classified as hypertensive PPGLs (70.6%) and 87 as normotensive PPGLs. A higher proportion of normotensive PPGLs than hypertensive PPGLs did not receive alpha presurgical blockade (P = 0.009). When we only considered those patients who received presurgical alpha blockers (200 hypertensive PPGLs and 76 normotensive PPGLs), hypertensive PPGLs had a threefold higher risk of intraoperative hypertensive crisis (OR 3.0 [95% 1.3-7.0]) and of hypotensive episodes (OR 2.9 [95% CI 1.2-6.7]) than normotensive PPGLs. When we compared normotensive PPGLs (n = 76) and non-PPGLs (n = 58), normotensive PPGLs had a fivefold higher risk of intraoperative complications (OR 5.3 [95% CI 1.9-14.9]) and a six times higher risk of postoperative complications (OR 6.1 [95% CI 1.7-21.6]) than non-PPGLs.

CONCLUSION

Although the risk of intraoperative hypertensive and hypotensive episodes in normotensive PPGLs is significantly lower than in hypertensive PPGLs, normotensive PPGLs have a greater risk of intraoperative and postoperative complications than non-PPGL adrenal lesions. Therefore, it is recommended to follow the standard of care for presurgical and anesthetic management of PPGLs also in normotensive PPGLs.

The silent variants of pituitary tumors: demographic, radiological and molecular characteristics

INTRODUCTION

Tumors of the anterior pituitary gland (PTs) are mostly benign tumors with a low prevalence, which has nevertheless increased with advances in brain radiology techniques. Nearly half of PTs are not associated with a clinical endocrine syndrome. These tumors have been indistinctly named non-functioning pituitary adenomas (NFPAs) or silent pituitary tumors (SPTs) and the mechanisms of silencing are not fully known.

AIM

To study the frequency and characterize the silent variant of PTs in a large local series, and to assess their pituitary adenohypophyseal gene expression.

METHODS

This observational, cross-sectional study was performed in a Pituitary Tumor Center of Excellence and involved 268 PTs. After identifying the different subtypes according to the immunohistochemical (IHC) expression of adenohypophyseal hormones, we studied their gene expression by RT-qPCR.

RESULTS

We found that silent tumors were larger and more invasive, but not more proliferative than their functional counterparts. The RT-qPCR complements the IHC typification of PTs, reducing the proportion of null-cell subtype. Finally, some silent PT subtype variants showed lower specific adenohypophyseal hormone gene expression than their functional counterparts, which may contribute to the absence of endocrine manifestations.

CONCLUSIONS

This paper highlights the importance of identifying the silent variant of the PTs subtypes. As expected, silent tumors were larger and more invasive than their functioning counterparts. However, there was no difference in the proliferation activity between them. Finally, the lower specific gene expression in the silent than in the functioning counterparts of some PTs subtypes gives insights into the silencing mechanisms of PTs.

Is Somatostatin Receptor and Dopamine Receptor profiling useful in the management of silent somatotroph tumors?

Silent somatotroph tumors (sSTs) are pituitary neuroendocrine tumors (PitNETs) which do not give rise to the clinical syndrome of acromegaly. Differently to their functioning counterparts, the adjuvant medical treatment with somatostatin analogues (SSAs) or dopamine receptors agonists (DAs) has been scarcely addressed in these tumors. As preliminary results of an ongoing research on silencing mechanisms involved in the pathogenesis of sSTs, we have characterized by qRT-PCR the expression of SSTRs and DRDs in a large series of 18 silent and 68 functioning STs. Although the expression of SSTR2 and SSTR5 was lower in sSTs than in functioning ones, we found a negative correlation between SSTR2 and the tumor size of the sSTs. Additionally, levels of expression of DRD2 were similar between the two subtypes suggesting a possible basis for the treatment of these tumors with SSAs and DAs.

[Surgical treatment of diaphyseal and comminuted fractures of the clavicle using a low profile anatomical plate]

OBJECTIVES

In this study we evaluate the treatment of displaced mid-shaft clavicle fractures or comminuted fractures with a third fragment using a superior anatomic plate.

MATERIALS AND METHODS

A retrospective study was conducted on 34 patients operated on between January 2006 and June 2010 with this type of fracture. Mean follow up was 25 months (6-54 months). By Robinson Classification, 12 cases were type 2B, 17 type 2B1 and 5 type 2B2. Clinical evaluation was performed with the VAS and Constant test. For the radiological evaluation, we used neutral AP projections, and another with 30 degrees of cranio-caudal inclination.

RESULTS

The mean pre-operative VAS was 6.5 (4-8) and the postoperative was 1 (0-2). The mean Constant test score was 85, with 30% good results and 70% excellent results. The mean consolidation time was 14 weeks.

CONCLUSION

Internal fixation of comminuted fractures with an anatomic plate, particularly those with a vertical third fragment and fractures type 2B, 2B1 and 2B2, provides a good treatment option, as it gives good functional results and minimises the incidence of non-union.

Medullary thyroid carcinoma and duodenal calcitonin-secreting neuroendocrine tumour: more than coincidence?

Neuroendocrine tumours (NETs) are a heterogeneous group of neoplasms whose management can be problematic. In many cases, multiple tumours may occur in the same patient or his or her family, and some of these have now been defined genetically, although in other cases the underlying gene or genes involved remain unclear. We describe a patient, a 63-year-old female, who was diagnosed with a medullary thyroid carcinoma (MTC), which was confirmed pathologically after thyroidectomy, but whose circulating calcitonin levels remained elevated after thyroidectomy with no evidence of metastatic disease. Subsequently, an entirely separate and discrete duodenal NET was identified; this was 2.8 cm in diameter and was removed at partial duodenectomy. The tumour stained immunohistochemically for calcitonin, and its removal led to persistent normalisation of the circulating calcitonin levels. There was no germline mutation of the RET oncogene. This is the first identification of a duodenal NET secreting calcitonin and also the first demonstration of a second tumour secreting calcitonin in a patient with MTC. We suggest that where calcitonin levels remain high after removal of a MTC a search for other NETs should be conducted.