Longitudinal Treatment Outcomes of Microsurgical Treatment of Neurosensory Deficit after Lower Third Molar Surgery: A Prospective Case Series

Objective

To prospectively evaluate the longitudinal subjective and objective outcomes of the microsurgical treatment of lingual nerve (LN) and inferior alveolar nerve (IAN) injury after third molar surgery.

Materials and Methods

A 1-year longitudinal observational study was conducted on patients who received LN or IAN repair after third molar surgery-induced nerve injury. Subjective assessments (“numbness”, “hyperaesthesia”, “pain”, “taste disturbance”, “speech” and “social life impact”) and objective assessments (light touch threshold, two-point discrimination, pain threshold, and taste discrimination) were recorded.

Results

12 patients (10 females) with 10 LN and 2 IAN repairs were recruited. The subjective outcomes at post-operative 12 months for LN and IAN repair were improved. “Pain” and “hyperaesthesia” were most drastically improved. Light touch threshold improved from 44.7g to 1.2g for LN repair and 2g to 0.5g for IAN repair.

Conclusion

Microsurgical treatment of moderate to severe LN injury after lower third molar surgery offered significant subjective and objective sensory improvements. 100% FSR was achieved at post-operative 6 months.     

Florid Suprascapular Neuropathy after Primary Rotator Cuff Repair Attributed to Suprascapular Notch Constriction in the Setting of Double Crush Syndrome

This report describes a patient who had an open repair of a small supraspinatus tendon tear performed 6 months after an arthroscopic acromioplasty with debridement had failed to provide pain relief. Three months prior to the tendon repair, he had a two-level cervical spine discectomy and fusion (C4–5, C5–6) that improved his neck pain. Florid suprascapular neuropathy was detected 10 weeks after the open rotator cuff repair. Evidence of some nerve recovery resulted in a long period of observation. But unsatisfactory improvement warranted decompression of the suprascapular notch, which was found to be very stenotic. At surgery, there was no evidence of neuroma, cyst, or other compressing lesion or tissue. Therefore, it was ultimately hypothesized that there was an exacerbation of a preexisting, but clinically unrecognized, entrapment of the suprascapular nerve in the suprascapular notch in the setting of cervical radiculopathy (primarily C5). Retrospectively it was also concluded that had this compressive etiology been recognized, it would have favored prompt decompression rather than the long observation period. Three years was required to achieve a good result following suprascapular notch decompression. The underlying C5 radiculopathy may have created a “double crush syndrome” that contributed to the propensity for injury and the prolonged recovery. There should be heightened awareness of this problem in patients who do not have satisfactory improvement in shoulder pain from previous shoulder and neck surgery.     

STRETCHING OF THE SCIATIC NERVE—A Means of Relieving Postoperative Pain Following Removal of Ruptured Lumbar Intervertebral Discs

Stretching the sciatic nerve for the relief of “sciatica” was frequently employed before 1900 and was subsequently abandoned, probably because it was done without sufficient scrutiny of the indications. The procedure has recently been employed in cases in which “sciatica” remains following the operative removal of ruptured intervertebral discs, and it has been instrumental in relieving postoperative “sciatica” when the cause was the formation of adhesions about the lumbar nerve roots. If the nerve root is compressed by recurrent disc protrusion or by adjacent bone, the manipulation usually increases the pain, a phenomenon that has been helpful from a diagnostic standpoint.     

Overexpression of c‐Jun inhibits erastin‐induced ferroptosis in Schwann cells and promotes repair of facial nerve function

Myelin undergoes various changes after nerve injury, and c‐Jun has a close relationship with Schwann cells (SCs). However, it remains unclear whether c‐Jun can be involved in nerve repair by regulating ferroptosis. To explore this, we first set up a facial nerve injury model and detected the changes of ferroptosis‐related proteins and c‐Jun by immunofluorescence and Western blot. Then, we cultured RSC 96 and pSCs, and studied the potential regulatory relationships by a combination of experimental methods such as CCK‐8, ELISA, immunofluorescence, qRT‐PCR, Western blot and viral transfection. Finally, we corroborated the role of c‐Jun through animal experiments. Our experiments revealed that ferroptosis occurs after facial nerve injury. Erastin decreased GPX4, c‐Jun proteins and GSH content, while PTGS2, NRF2, HO‐1 proteins, MDA, Fe²⁺ and ROS contents increased. This effect was inhibited after c‐Jun overexpression but was reversed after the addition of c‐Jun siRNA. Besides, we proved in vivo that c‐Jun could inhibit ferroptosis and promote the recovery of facial nerve function. In conclusion, our study identified the relationship between c‐Jun and ferroptosis during peripheral nerve injury repair, which provides new ideas for studying peripheral nerve injury and repair.     

PAROTID TUMOR OPERATIONS—The Case Against Enucleation

So-called mixed “encapsulated” parotid tumors are best managed by surgical procedures which avoid contact with the “capsule.” Enucleation is often a hazardous and incomplete procedure. Subtotal or total parotidectomy with exposure of the facial nerve to avert accidental damage to it is the treatment of choice.Microscopic study of the periphery of such tumors reveals that the “capsule” does not fully encapsulate; hence, enucleation and lesser procedures may leave neoplastic tissue behind.Surgical procedures to achieve complete excision without endangering the facial nerve were carried out in 123 cases. There was local recurrence in one case.     

Brain-Derived Neurotrophic Factor from Bone Marrow-Derived Cells Promotes Post-Injury Repair of Peripheral Nerve

Brain-derived neurotrophic factor (BDNF) stimulates peripheral nerve regeneration. However, the origin of BNDF and its precise effect on nerve repair have not been clarified. In this study, we examined the role of BDNF from bone marrow-derived cells (BMDCs) in post-injury nerve repair. Control and heterozygote BDNF knockout mice (BDNF+/−) received a left sciatic nerve crush using a cerebral blood clip. Especially, for the evaluation of BDNF from BMDCs, studies with bone marrow transplantation (BMT) were performed before the injury. We evaluated nerve function using a rotarod test, sciatic function index (SFI), and motor nerve conduction velocity (MNCV) simultaneously with histological nerve analyses by immunohistochemistry before and after the nerve injury until 8 weeks. BDNF production was examined by immunohistochemistry and mRNA analyses. After the nerve crush, the controls showed severe nerve dysfunction evaluated at 1 week. However, nerve function was gradually restored and reached normal levels by 8 weeks. By immunohistochemistry, BDNF expression was very faint before injury, but was dramatically increased after injury at 1 week in the distal segment from the crush site. BDNF expression was mainly co-localized with CD45 in BMDCs, which was further confirmed by the appearance of GFP-positive cells in the BMT study. Variant analysis of BDNF mRNA also confirmed this finding. BDNF+/− mice showed a loss of function with delayed histological recovery and BDNF+/+→BDNF+/− BMT mice showed complete recovery both functionally and histologically. These results suggested that the attenuated recovery of the BDNF+/− mice was rescued by the transplantation of BMCs and that BDNF from BMDCs has an essential role in nerve repair.     

Pulmonary Contusion in Children due to Rubber Bullet Injuries

Three cases of pulmonary contusion occurred in children as a result of injuries from “rubber bullets.” Radiological changes were evident soon after the injury, and in one case these persisted for two months. Symptoms disappeared quickly in all three cases.     

T‐cell infiltration,contribution and regulation in the central nervous system post‐traumatic injury

T cells participate in the repair process and immune response in the CNS post‐traumatic injury and play both a beneficial and harmful role. Together with nerve cells and other immune cells, they form a microenvironment in the CNS post‐traumatic injury. The repair of traumatic CNS injury is a long‐term process. T cells contribute to the repair of the injury site to influence the recovery. Recently, with the advance of new techniques, such as mass spectrometry‐based flow cytometry, modern live‐cell imaging, etc, research focusing on T cells is becoming one of the valuable directions for the future therapy of traumatic CNS injury. In this review, we summarized the infiltration, contribution and regulation of T cells in post‐traumatic injury, discussed the clinical significance and predicted the future research direction.     

Economic Aspects of “Whiplash” Injury

The term “whiplash,” used to describe a neck injury received in an automobile accident, has no foundation in medical science to support the complaints of persons suing for damages. The term is gaining unwarranted popularity as a term describing an injury, even though there are no clinical or pathological findings to support it.“Whiplash” cases today account for an estimated 30 per cent of all injuries in automobile accidents. Direct compensation for damages paid to persons injured in automobile accidents in the United States in 1961 amounted to approximately one billion, seven hundred million dollars. It has been estimated that five hundred and eighty million dollars of that amount was paid in compensation on allegation of neck injuries.     

MANDIBULAR HERPES ZOSTER—With Report on the Use of Cortisone in a Case with Geniculate Ganglion Symptoms

Herpes zoster, an acute specific viral infection, occurs more commonly than is generally supposed. It should be differentiated from other diseases involving the ear and skin; it must be considered as a possible etiologic agent in some palsies of the facial, glossopharyngeal or vagal nerves.The type of cephalic herpes zoster should be carefully differentiated; cases involving the “geniculate zone” may be other than “Ramsay Hunt''s syndrome.” This syndrome is now defined as a herpes zoster eruption of the external ear at the “geniculate zone” with involvement of the seventh or seventh and eighth nerves.The “topognostic” method is the best for determining the level at which the facial nerve has been affected.It is questioned whether there is a single outstanding therapeutic agent for this disease. Cortisone had no apparent therapeutic effect in a case reported herein.     

Axonally transported proteins associated with axon growth in rabbit central and peripheral nervous systems

In an effort to determine whether the “growth state” and the “mature state” of a neuron are differentiated by different programs of gene expression, we have compared the rapidly transported (group I) proteins in growing and nongrowing axons in rabbits. We observed two polypeptides (GAP-23 and GAP-43) which were of particular interest because of their apparent association with axon growth. GAP-43 was rapidly transported in the central nervous system (CNS) (retinal ganglion cell) axons of neonatal animals, but its relative amount declined precipitously with subsequent development. It could not be reinduced by axotomy of the adult optic nerves, which do not regenerate; however, it was induced after axotomy of an adult peripheral nervous system nerve (the hypoglossal nerve, which does regenerate) which transported only very low levels of GAP-43 before axotomy. The second polypeptide, GAP-23 followed the same pattern of growth-associated transport, except that it was transported at significant levels in uninjured adult hypoglossal nerves and not further induced by axotomy. These observations are consistent with the “GAP hypothesis” that the neuronal growth state can be defined as an altered program of gene expression exemplified in part by the expression of GAP genes whose products are involved in critical growth-specific functions. When interpreted in terms of GAP hypothesis, they lead to the following conclusions: (a) the growth state can be subdivided into a “synaptogenic state” characterized by the transport of GAP-23 but not GAP-43, and an “axon elongation state” requiring both GAPs; (b) with respect to the expression of GAP genes, regeneration involves a recapitulation of a neonatal state of the neuron; and (c) the failure of mammalian CNS neurons to express the GAP genes may underly the failure of CNS axons to regenerate after axon injury.     

INITIAL CARE OF ACUTE BACK INJURIES

The mechanism of injury to the back should be obtained with the utmost accuracy and set down in the history as a separate paragraph under that heading. This is usually best obtained by questioning and requestioning the patient during the course of the examination. A history of any previous back affections should also be obtained at the first visit.The detailed examination of the back is not complete without a general physical examination.X-ray studies should be done immediately in all cases in which the injury has been caused by direct violence or forceful indirect violence (as in “jackknife” injury).Terms such as “disc disease,” “ruptured intervertebral disc” and various others that convey a similar meaning should not be used as the initial diagnosis and should be withheld until such a diagnosis is definitely established.The plan of treatment may include a period in hospital or of rest at home, or it may be carried out with the patient ambulatory. Corsets and braces should be prescribed only when they are to serve a definite function and the same can be said of physiotherapy.     

Improvement of Sciatic Nerve Regeneration Using Laminin-Binding Human NGF-β

Background

Sciatic nerve injuries often cause partial or total loss of motor, sensory and autonomic functions due to the axon discontinuity, degeneration, and eventual death which finally result in substantial functional loss and decreased quality of life. Nerve growth factor (NGF) plays a critical role in peripheral nerve regeneration. However, the lack of efficient NGF delivery approach limits its clinical applications. We reported here by fusing with the N-terminal domain of agrin (NtA), NGF-β could target to nerve cells and improve nerve regeneration.

Methods

Laminin-binding assay and sustained release assay of NGF-β fused with NtA (LBD-NGF) from laminin in vitro were carried out. The bioactivity of LBD-NGF on laminin in vitro was also measured. Using the rat sciatic nerve crush injury model, the nerve repair and functional restoration by utilizing LBD-NGF were tested.

Findings

LBD-NGF could specifically bind to laminin and maintain NGF activity both in vitro and in vivo. In the rat sciatic nerve crush injury model, we found that LBD-NGF could be retained and concentrated at the nerve injury sites to promote nerve repair and enhance functional restoration following nerve damages.

Conclusion

Fused with NtA, NGF-β could bind to laminin specifically. Since laminin is the major component of nerve extracellular matrix, laminin binding NGF could target to nerve cells and improve the repair of peripheral nerve injuries.     

“Sensory Switching” in Elbow Reconstruction

In the treatment of the soft tissue defect of the elbow, flap reconstruction is necessitated in many cases because of thinness of soft tissue at this region. In addition, reacquirement of tactile sensation is desirable because of the anatomical and specific functions of the elbow. Of three cases treated for elbow defects, one was reconstructed with a pedicled island forearm flap containing the lateral cutaneous nerve of the forearm, another was reconstructed with a venoneuro-accompanying artery fasciocutaneous flap (VNAF flap) containing the basilic vein, and the third with the VNAF flap containing the cephalic vein. The three cases demonstrated a sudden change of sensory territory 4 to 6 months after surgery, which was confirmed by touching the reconstructed region with patients'' eye-closed: from its original territory to the elbow in a “switching”-like action. Here we describe and discuss the concept of “sensory switching.”     

Injuries of the fingers and hands; a review of cases from the standpoint of compensation

Review of records in cases of injury to the hand that come before the California Industrial Accident Commission indicate that:1. Primary closure at a suitable level in finger amputations is often preferable to plastic repair.2. Complications incident to plastic repair in minor injuries frequently increase disability and cost to employer.3. Tendon injury resulting from strain is a frequently overlooked cause of disability.     

Allogeneic Bone Marrow Transplant from MRL/MpJ Super-Healer Mice Does Not Improve Articular Cartilage Repair in the C57Bl/6 Strain

Background

Articular cartilage has been the focus of multiple strategies to improve its regenerative/ repair capacity. The Murphy Roths Large (MRL/MpJ) “super-healer” mouse demonstrates an unusual enhanced regenerative capacity in many tissues and provides an opportunity to further study endogenous cartilage repair. The objective of this study was to test whether the super-healer phenotype could be transferred from MRL/MpJ to non-healer C57Bl/6 mice by allogeneic bone marrow transplant.

Methodology

The healing of 2mm ear punches and full thickness cartilage defects was measured 4 and 8 weeks after injury in control C57Bl/6 and MRL/MpJ “super-healer” mice, and in radiation chimeras reconstituted with bone marrow from the other mouse strain. Healing was assessed using ear hole diameter measurement, a 14 point histological scoring scale for the cartilage defect and an adapted version of the Osteoarthritis Research Society International scale for assessment of osteoarthritis in mouse knee joints.

Principal Findings

Normal and chimeric MRL mice showed significantly better healing of articular cartilage and ear wounds along with less severe signs of osteoarthritis after cartilage injury than the control strain. Contrary to our hypothesis, however, bone marrow transplant from MRL mice did not confer improved healing on the C57Bl/6 chimeras, either in regards to ear wound healing or cartilage repair.

Conclusion and Significance

The elusive cellular basis for the MRL regenerative phenotype still requires additional study and may possibly be dependent on additional cell types external to the bone marrow.     

Femoral Hernia in the Female

A study of 384 consecutive femoral herniorrhaphies performed upon female patients admitted to Shouldice Hospital, Toronto, during a 19-year period was carried out. Its main purpose was to describe the techniques used and to evaluate the results obtained. A careful 10-year follow-up plan for all cases existed.Two hundred and ninety-three operations were performed for the repair of simple femoral hernia; 91 were performed for the repair of femoral hernia which had developed following an initial ipsilateral inguinal or femoral repair performed previously, either in this hospital or elsewhere.The basic repair was subinguinal. Four modifications are described, one entirely subinguinal and three combined with exploration of the inguinal canal.The recurrence rate for simple femoral hernia in the female was 1.3% and for “recurrent” femoral hernia in the female, 5.5%.     

SALIVARY GLAND TUMORS

In a review of a series of 248 salivary gland tumors, seen over a 28-year period, all pathologic material was brought up to date by reclassification according to more recent criteria and nomenclature. In parotid tumors, a probable lowered recurrence rate and a definite decrease in incidence of permanent facial nerve paralysis was found in the more recent cases in which the “Y” incision was used, with identification of the seventh nerve as it leaves the stylomastoid foramen. The five-year recurrence rate for primary mixed tumor was 8.3 per cent, and in recurrent cases it was found to be 18.1 per cent.Of 44 patients with malignant salivary gland tumors in all sites who were observed for five years or more, 32 or 72.7 per cent survived five years.