Behnam Aghabeigi on the management of unilateral condylar fractures

No area of maxillofacial trauma stimulates more controversy than the management of a fractured mandibularcondyle. Fractures of the mandibular condyle are thought to account for about 35% of all mandibular fractures, but our experience suggests that this is an overestimate.

A recent multicentre national audit in the UK2reported a suboptimal outcome in up to 30% of patients with unilateral condylar fracture managed by the traditional techniques of either closed reduction or observation, although the follow-up period was short. If the findings are true then this is an unacceptably high complication rate. Consequently the pendulum has swung towards accurate anatomical relocation of the fractured segments by open reduction and internal fixation (ORIF) in the hope that this will improve outcome.

Whilst the proponents of both open and closed reduction passionately debate the appropriate choice of treatment, a review of publications showed a paucity of good quality scientific evidence to support either treatment.

This prospective study was designed to investigate the outcome of treatment of unilateral condylar fractures with ORIF on the hypothesis that such treatment may convey superior results by allowing adaptive processes to act maximally during the recovery period.

Patients and Methods used by Ben Aghabeigi Birmingham

Adult patients who presented to the maxillofacial units at University College London Hospitals and the Queen Victoria Hospital, East Grinstead were recruited prospectively.

According to Aghabeigi dentist all patients over 16 years of age with unilateral condylar fractures were examined. Those with unilateral condylar fractures and normal occlusions were managed conservatively, by instituting a soft diet for 6 weeks and early mobilization. These patients were not entered into the study.

Patients who had an isolated unilateral condylar fracture and deranged occlusion were placed in elastic traction for 7–10 days, the exact time being decided by the date of the next available clinic. Any patient with a deranged occlusion at review was offered open reduction and internal fixation. It was felt that sufficient time would have elapsed since the original presentation that compounding factors such as tissue oedema, muscle spasm and effusion or haemarthrosis would have resolved, and that any resultant malocclusion was caused solely by condylar malposition.

A second group of patients was also recruited into the study. Adult patients who presented with deranged occlusion, and a unilateral displaced or dislocated condylar fracture plus another mandibular fracture that itself required osteosynthesis, were offered ORIF of all fracture sites. The criteria for offering ORIF of the associated condyle were the same as those described by Eckelt and Rasse,3namely medial dislocation of the condyle ; displaced fractures with 95 mm bone overlap; or complete loss of bone contact.

The surgical technique used was standardized and five surgeons operated on the patients. All concerned were either of consultants grade or had at least 3 years’ registrar experience. Surgical access was by a retromandibular approach, which was occasionally supplemented with a standard preauricular skin incision. The fractures were fixed with 2-mm titanium miniplates.

Outcome measures involved each patient being examined according to a standard protocol together with standardized radiographic assessment (orthopantomograms and posterior–anterior mandibular radiographs).

All authors assessed the preoperative and postoperative radiographs for each patient.

The outcome measures considered to be important were broadly akin to those described by Walker5and comprised:

1. The restoration of the preinjury occlusion. This was assessed by the operating surgeon together with questions to the patient.

2. Restoration of normal mouth opening in excess of 40 mm. Inter-incisal clearance was measured with a Willis gauge.

3. Pain-free mouth opening, which was assessed by asking the patients.

4. Full range of mandibular excursions, assessed clinically by the operating surgeon.

5. Restoration of facial and mandibular symmetry, assessed clinically by the operating surgeon. We accept that some of the above are subjective and open to inter-operator variation, and therefore criticism, but on a pragmatic level this was the best we thought that we could achieve.

Checking the Results with Ben Aghabeigi gdc

A total of 54 consecutive patients was entered into the study: 24 had isolated unilateral fractures, and the remaining 30 had a synchronous parasymphyseal fracture. Forty-two of the patients were males (78%). Thirty-three of the 54 patients underwent ORIF of their condylar fracture with miniplate osteosynthesis. The remaining 21 condylar fractures were treated with elastic traction alone. No patient in this latter group had a synchronous mandibular fracture. No patient whose conservative treatment had failed refused ORIF at the 7–10 day appointment.

The nomenclature we used to classify the subsets of condylar fracture was the same as that proposed by Lindahl6: intracapsular, condylar neck or subcondylar. These fractures were further subdivided by assessing the relationship of the condylar fragment to the rest of the mandible. This led to a subclassification of undisplaced, displaced medially or laterally, over-riding anteriorly or posteriorly, or complete loss of bony contact. Afurther subset was also generated when we assessed the rela- tionship of the condylar head to the glenoid fossa, giving undisplaced, displaced and dislocated categories.

A branch of the facial nerve was encountered during 19 retromandibular dissections (35%), which is similar to the figure quoted by Ellis and Dean.7With careful surgical technique and gentle retraction the nerve branch can be mobilized without compromising its function or impeding access to the fracture site. All patients had normally functioning facial nerves at 1-month review. In the case of fracture dislocations the retromandibular approach occasionally has to be supplemented by a standard preauricular approach to gain control of the condylar fragment and to facilitate accurate anatomical reduction.

Several authors have combined miniplate osteosynthesis with intermaxillary fixation (IMF). This negates one of the main advantages of ORIF, and contravenes the established principle of early mobilization to prevent ankylosis. Therefore our patients were not placed in wire IMF during the postoperative period, but three of them (10%) did require guiding elastic traction for the first 10 postoperative days to achieve their premorbid occlusion.

Only 32 of 54 patients attended for review; such poor compliance is not unusual in this group of patients. Of those reviewed 25 had ORIF, and the remaining 7 had been managed with elastic traction alone. The follow-up period ranged from 1 month to 3 years with a median of 14.5 months. All patients treated with ORIF had good postoperative occlusion assessed both objectively (by clinical assessment) and subjectively (by asking the patient how the bite felt). Nineteen patients (60%) had some degree of mandibular deviation on opening (all 7 in the conservative group and 12/25 in the ORIF group).

However, this was of greater concern to the clinicians than to the patients. Two patients (6%) have been left with chronic pain at the condylar fracture site, both of whom were conservatively treated.

Mouth opening varied between the two groups. In the ORIF group the mean interincisal opening was 42 mm (range 37–52), and in the elastic traction group the mean was 32 mm (range 28–36). These figures compare favourably with those previously reported4which showed interincisal clearance to be significantly improved in patients with bilateral condylar fractures treated by ORIF (mean 44 mm) compared with IMF (mean 28 mm).

One of the criticisms of ORIF has been the length of time taken to do this procedure in view of the limited access. Whilst we accepted this initially, with increasing exposure to the technique our operative time decreased from a mean of 120 minutes/condyle to 40 minutes/condyle.

DISCUSSION

The management of unilateral condylar fractures remains controversial. There have been as many studies published in the world that favour ORIF as there have been that oppose it. Indeed, Hayward and Scott quoted a similar discussion reported in the American Journal in 1945, debating just this issue. It has been our previous experience that an unacceptably large number of patients who have been managed conservatively have had suboptimal functional outcomes. This view has been supported in a recently published national survey. We therefore felt it necessary to compare outcome in the two groups prospectively.

Zide and Kent11described their indications for plating condylar fractures, which included displacement of the condyle into the middle cranial fossa, lateral extra-capsular displacement of the condyle, inability to achieve adequate reduction using closed techniques, and invasion of the joint by a foreign body such as a gunshot. We have found that these criteria are seldom met in everyday maxillofacial practice, so we used the criteria described by Eckelt and Rasse3to decide who would be offered ORIF, with the aims of treatment being those previously described by Walker.5

ORIF of the condyle has not gained widespread popularity with surgeons, as it is perceived to be a difficult and time-consuming operation. Our experience has shown that although there is a fairly steep learning curve we were able to reduce our operating time considerably from 120 minutes to about 40 minutes/condyle.

Surgical access to the condyle was by a retromandibular approach, and our initial fears of damaging the facial nerve have not been realized. This technique provides good access to the condylar fracture and we have extended its application to include inverted ‘L’ ramus osteotomies and costochondral grafting procedures.

Three of 25 patients (12%) had a transient weakness of the buccal branch of the facial nerve that recovered fully within 3 weeks. This indicates a low incidence of facial nerve morbidity associated with this approach. The retromandibular incision is associated with good cosmesis as assessed by both patient and surgeon.

For more information about Behnam Aghabeigi visit here : http://benaghabeigi.co.uk/

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Behnam Aghabeigi studies patients with chronic facial pain

Facial arthromyalgia (FAM) or the temporomandibular joint pain dysfunction syndrome is a common condition in which patients complain of pain and tenderness in one or both temporomandibular joints (TMJ), often with limitation of jaw opening informs Dr. Behnam Aghabeigi Birmingham. The condition is four times more common in females than males and there are many reports linking these symptoms to adverse life events, stress or the lack of emotional support. This condition can occur independently or with other non-muscular non-joint pain in the face (atypical facial pain, AFP) or teeth (atypical odontalgia, AO). These are also commonly related to idiopathic head, neck and back pain, irritable bowel and pruritus. The facial pains are best controlled with tricyclic antidepressants even in the absence of depression. Recently we have shown that these patients also have impaired excretion of conjugated tyramine, a biological trait marker seen in endogenous depression suggesting a common metabolic disturbance predisposes to both pain and depression.

However, the precise underlying biochemical mechanisms leading to both pain and joint dysfunction remain to be established. In an attempt to account for the joint pain and dysfunction Dr. Ben Aghabeigi Birmingham’s attention was drawn to studies claiming to demonstrate that emotional stress and pain in animals were associated with an increased generation of free radical@-’ and by the observation that stress induced damage to the gastric mucosa was related to free radical production. ‘,i” Furthermore, there have been reports that free radical activity in synovial fluid from the knee joints of rheumatoid patients correlates with the severity of the disease.” A free radical is any molecule or atom that contains one or more unpaired electrons rendering it highly reactive. Most biological molecules such as O2 or H,O are non-radicals, containing only paired electrons.

In addition to causing pain in animals, in vitro experiments have shown that free radicals depolymerise hyaluronic acid producing lower synovial fluid viscosity,” which might impair lubrication and lead to meniscal hesitation and clicking, as originally proposed by Toller.i3 There has also been evidence that free radicals are associated with cartilage damage14 and that they can stimulate bone resorption.” Furthermore, the demonstration of the presence of eicosanoids in various inflammatory joint diseases,” which could be the product of a free radical and or neuropeptide synovitis, would fit their known role as one of the important mediators of chronic algesia and hyperalgesia. Therefore we have examined the possibility that FAM may, in part, result from the inappropriate production of free radicals in susceptible individuals.

Three parameters of free radical generation were measured in patients presenting with overt symptoms of FAM and/or a history of idiopathic oro-facial pain (AFP and AO): (I) Systemic free radical activity was studied by a comparison of the free radical production of 2,3-dihydroxybenzoic acid (DHB) from an oral dose of aspirin as opposed to the normal aspirin metabolic product 2,5-DHB.17

Intra-articular free radical activity was investigated by two methods.

One was a thiobarbituric acid (TBA) assay of saline TMJ aspirates to test for intra-articular production of lipid peroxidation products” and (III) the second was measurement of the production of intra-articular hyperalgesic eicosanoids PGE,, LTB, and 15-HETE.

Materials and Methods used by Dr. Ben Aghabeigi Birmingham

Patients

Three sets of patients were recruited for this study. Systemic free radical activity was studied in the first group of patients who were diagnosed as having chronic FAM and/or other idiopathic oro-facial pain of more than 3 months duration. Intra-articular free radical activity was studied in groups II and III which comprised patients with unilateral symptoms of TMJ pain which had been unresponsive to 12 weeks tricyclic antidepressant therapy and were undergoing TMJ arthroscopy under general anaesthesia. All the subjects gave their informed consent and none had any other joint disease or known or suspected history of allergy to aspirin. Ethical approval was obtained for all procedures.

Group I (systemic free radical activity): 10 pain patients (age range 26-64, mean 41.8 + 11; 9 females, 1 male) and 10 healthy, age- and sex-matched volunteers with no prior history of idiopathic pain were recruited as controls (age range 29-60, mean 42.129.6). These patients and control subjects had 10 ml of venous blood drawn in heparinised tubes and voided their bladders to provide a urine sample. Each subject was then administered an oral dose of 1.2 g of aspirin and after 2 h repeat blood and urine samples were collected. The blood samples were centrifuged immediately and the plasma and urine samples stored at – 70°C until assayed for 2,3-DHB.

Group II consisted of 18 patients (age range 22-49, mean 33.2+ 8.1; 13 females, 5 males). Two hours before arthroscopy the patients were administered 1.2 g of Aspirin orally in order to ensure equilibration between the plasma and synovial fluid. At arthroscopy 1 ml of normal saline was injected into the joint spaces bilaterally, allowed time to mix with the synovial fluid and aspirated through the same needle. Specimens with overt contamination with blood were discarded. The aspirate volumes were determined, 50 ul removed for haemoglobin assay and the remainder was centrifuged immediately before the supernatants were stored at -70°C. A venous blood sample was drawn into heparinised tubes at the same time as the synovial aspirates were collected, centrifuged and the plasma stored at -70°C until assayed for lipid peroxidation products by TBA assay.

Group III consisted of 15 patients (age range 15-41, mean 28.3 +7.4; 9 females, 6 males). Synovial aspirates were collected as described above and retained for hyperalgesic eicosanoid analysis, specifically prostaglandin E2 (PGE2), leukotriene B, (LTB,) and 15-hydroxyeicosatetraenoic acid ( 15HETE). These subjects did not receive aspirin because of its potential inhibitory effect on eicosanoid production.

Biochemical analyses

(a) Measurement of plasma and urine Measurement of plasma and urine 2,3- and 2,5-dihydroxybenzoic acid (DHB) was by a modification of the methods of Grootveld and Halliwell” using HPLC coupled to electrochemical detection. All samples were used immediately or stored at – 70°C until analysed.

(i) Plasma sample preparation for the DHB assay. Samples (1 ml) were acidified with 50 ul of 1 M HCI and 20 ul of an internal standard of 3,4-DHB (100 PM) added before the samples were extracted with 10 ml of ethyl acetate. The samples were then centrifuged at 1500 g for 10 min before the upper organic layer was decanted into a clean dry tube and reduced to dryness under a stream of air in a water bath at 40°C. Once dry the samples were redissolved in 200 nl of mobile phase and 50 ~1 of 1 M HCl was added prior to analysis.

(ii) Urine sample preparation for DHB assay. Samples (5 ml) were acidified with 1 ml 1 M HCl before being extracted twice with 10 ml of ethyl acetate. The combined ethyl acetate extracts were taken to dryness under a stream of air in a water bath at 40°C. The residues were reconstituted in 250 ul of 0.2 M HCl and subsequently diluted 1 in 20 or 1 in 50 with 0.2 M HCl before final analysis.

(iii) HPLC purification and electrochemical detection of DHBs. After the initial extraction of both the plasma and the urine samples, the HPLC purification of 2,3- and 2,5-DHBs were the same, with a minor modification to the detection system to facilitate a single run determination of the urinary levels of 2,5-DHB due to the large amounts of this aspirin metabolite found in urine. HPLC separations were run under isocratic conditions using a SpectraPhysics SP8800 pump with a Brownlee 5 pm ODS reverse phase column (250 x4.6 mm) coupled to an EDT instruments LCA 16 electrochemical detector equipped with a glassy carbon working electrode and a Ag/AgCl reference electrode operated in the oxidation mode. The mobile phase was 30 mM sodium titrate/27.7 mM sodium acetate buffer (pH 4.75) at a flow rate of 1 ml min- i. The mobile phase was sparged with helium gas and the eluent monitored electrochemically at an electrode potential of + 0.6 V.

When the urine samples were analysed it was found to be possible to obtain quntifiable peaks equivalent to 2,3- and 2,5-DHBs in a single run when the recorder sensitivity was decreased lo-fold after the elution of the 2,3-DHB peak.

Synovial analyses for lipid peroxidation

(b) Thiobarbituric acid test

A modified method of Rowley et al.” was used in this study; briefly, 125 yl of sample-plasma or synovial Auid- was added to 250 ul of TBA solution (1% w/v in 50 mM sodium hydroxide), 250 ul hydrochloric acid (25% v/v) and 200 ul of water; 125 ul of water was used in the place of sample as a negative control. The tubes were tightly capped and heated at 100°C for 1 h, after which they were allowed to cool to room temperature before being extracted into 1.5 ml l-butanol with vigorous mixing for 2 min. The samples were then centrifuged at 1500 g at 4°C for 15 min and the absorbance of upper organic layer determined at 532 nm.

(c) Haemoglobin measurement

Haemoglobin levels in the samples were quantified using a commercial calorimetric assay (Sigma Chemical Co.). Some of the samples were found to have low levels of haemoglobin which could only be measured by increasing the volume of the sample in the assay system from 20 ul to 50 ~1.

(d) Salicylate assat,

Salicylate was measured in both joint aspirate and venous blood by a modified method of Grootveld and Halliwelli7 using high performance liquid chromatography (HPLC) and UV detection. Samples (200 ~1) were treated with 25 ul of 1 M HCl before being extracted with 10 ml of diethyl ether. After separation, the ether layer was evaporated in a water bath at 40°C and the residue was dissolved in 225 ulof the HPLC mobile phase containing 5% (v/v) 1 M HCl. Samples not assayed immediately were stored at -70°C until used. Separation was done on a SpectraPhysics SP8800 HPLC pump operated in isocratic mode using a Shandon 5 m ODS reverse-phase column (250 x 4.6 mm). The mobile phase was 30 mM sodium titrate/27.7 mM sodium acetate buffer (pH 4.75) and methanol (94: 6) at a flow rate of 1 ml min-‘. The mobile phase was sparged with helium gas and the eluent monitored at 254 nm.

(e) Measurement of eicosanoids

Synovial aspirates from symptomatic and symptomfree joints were analysed for the presence of PGE,, LTB, and 15-HETE using commercial radioimmunoassay kits (Amersham International). The assays were conducted according to the manufacturer’s instruction.

Statistical analysis

A student’s r-test was used for analysing the parametric data in patients vs controls and symptomatic vs asymptomatic joints.

Results

Group I

Healthy control subjects and patients presenting with chronic idiopathic oro-facial pain did not have statistically different circulating levels of the principle 2,5-DHB metabolite of aspirin indicating that the metabolic factors governing aspirin clearance were not different between the two groups. However, the circulating levels of 2,3-DHB, the suggested product of free radical activity,” was significantly elevated in the pain patients, whereas 5 out of 10 of the control subjects were found to have no detectable levels of this compound. The urine concentrations of both metabolites did not differ between the groups.

Group II

The yield of aspirate ranged from 500 ul to 1050 ul, there being no significant volumetric difference between the symptomatic and symptom-free joints. There was no significant difference in the levels of TBA-RS between the synovial fluids from the symptomatic and symptomless joints. Approximately half of the samples had haemoglobin contamination, but the contribution to the measured levels of TBA-RS did not significantly alter the analysis of the data. The synovial fluid volume was calculated using a concentration volume equation based on the plasma to TMJ aspirate salicylate ratio.ig This ratio was not significantly different between the symptomatic and symptomless joints, reflecting the absence of any difference in synovial fluid volume between painful and pain-free joints.

Group III

The presence of high levels of 15-HETE, but unmeasurable amounts of both PGE, and LTB, were found in both symptomatic and symptom-free synovial aspirates (Table 2). There was no statistical difference between the levels of 15-HETE in the synovial fluids from symptom-free and painful joints.

Discussion with Aghabeigi dentist

We have measured the levels of 2,3-DHB in both the circulation and in the urine of a group of 10 patients attending a clinic for chronic idiopathic oro-facial pain, before and after the administration of 1.2 g of aspirin and these levels have been compared to ageand sex-matched control subjects (Table 1). There was no indication that either group had differences in their innate abilities to metabolise Aspirin, as assessed by the production of 2,5-DHB, the major product of mammalian metabolism of aspirin. However, there were significantly higher levels of the free radical generated 2,3-DHB in the plasma of the patient group as compared to the control subjects. It has been proposed that the production of 2,3-DHB from an oral dose of aspirin results from a free radical reaction with salicylate.” This would support the hypothesis that patients with chronic idiopathic pain which is commonly stress related appear to generate increased free radicals or have some impairment in their scavenging metabolism.

The urinary levels of 2,3-DHB was higher in patients as compared to the controls. Although this was not statistically significant, it could be biologically important. We are not competent to comment further on the complexity of urinary free radical metabolism, which probably required some form of clearance measurement. During the past decade, saline aspirates of the upper joint space of the TMJ have been analysed for the presence of various mediators of pathological conditions.20-24 In this study we have also analysed saline aspirates, from patients presenting with a history of chronic FAM who were undergoing arthrostopic examination, for the potential to generate, in vivo, free radicals and intra-articular eicosanoids. We believe that this approach is fraught with difficulties, especially as the volumetric yield from a collection of TMJ aspirate is variable, in our case ranging from 500 ul to 1050 ~1. The volume collected is probably dependent on operator technique and the patency of the joint space.

However, the mean volume of the aspirates collected in this study is much higher than previously reported” or than that collected in a pilot study done in our laboratory.” Arthroscopic joint trauma, giving rise to haemoglobin and cellular contamination of some of the samples was an indication of an important source of error. This was controlled by the preoperative aspirin and by ensuring that centrifugation of the aspirates was carried out immediately, and would also explain, at least in part, previously reported unusually high levels of inflammatory mediators that are not appropriate to this condition.21 This is an important observation that has not previously been commented on by other workers, who have found levels of neuropeptides, prostaglandins and leukotrienes to be higher in TMJ synovial fluid than those found in the synovial fluid collected from the inflamed knee joint in gout.

Although measurement of TBA-RS is one of the most widely used single assays for determining lipid peroxidation indicating free radical activity, it has been criticised for its lack of specificity when applied to human body fluids. i9 It is interesting that we have also found TBA-RS in the saline aspirates from both symptomatic and non-symptomatic TMJs of patients with FAM and that there is no statistical difference between the sides. This suggests that other as yet unknown algesic factors contribute to the localisation of the pain and dysfunction. An alternative influence may be the suspension of masticatory activity by a patient who has fasted overnight prior to the general anaesthetic.

An interesting piece of supporting evidence for the involvement of free radicals in the pathogenesis of FAM is our demonstration of high intra-articular concentrations of the hyperalgesic mediator 15-hydroxyeicosatetraenoic acid ( 15-HETE), whose synthesis involves the free radical mediated process of lipid peroxidation of arachidonic acid, in synovial fluid. We were unable to demonstrate the presence of either prostaglandin E2 (PGE,) or leukotriene B4 (LTB,). It is worth repeating that the eicosanoid levels found by previous investigators seem to be artifactually raised even when compared to severe inflammatory disease in other joints.“j It is of importance that hyperalgesia induced by 15-hydroperoxyeicosatetraenoic acid ( 15-HPETE) in an experimental animal can substantially prolong the algesic effect of substance P(SP) producing a chronic pain model not dissimilar to FAM. This is not inhibited by non-steroidal anti-inflammatory analgesics apart from dipyrone.

Furthermore, a SP antagonist can block this effect. These findings correlate with other studies which have identified neuropeptides in the synovial fluid from the TMJ27,28 and our own observations2’ which have demonstrated that the TMJ capsule is not only richly innervated by SP neuronal tissue, but also other neurogenic peptides including calcitonin gene-related peptide, neuropeptide Y and vasoactive intestinal polypeptide. One of the major clinical problems in controlling FAM is the poor response to non-steroidal anti-inflammatory analgesics, which would correlate with the role of hyperalgesic 15-HPETE as being more important than the prostaglandins such as PGE,. As stated there were no significant differences between the symptomatic and symptom-free joints with respect to TBA-RS, 15-HETE or synovial fluid volume.

Unfortunately, as it was not ethically possible to obtain saline aspirates from the joints of healthy age- and sex-matched pain-free adults, one can only speculate that these levels found represent the pathological process. This absence of difference is not completely surprising considering that a systemic biochemical disorder would be reflected in both joints at the ends of a single bone. Furthermore, the mirror imaging of inflammatory responses in other paired joints in the body which lack the unique anatomical and functional characteristics of TMJ has been attributed to neurophysiological influences.30 However, the presence of potential pain mediators in the symptomless joints also suggests the importance of other factors such as local neuropeptide or cytokine release which may be dependant on asymmetrical masticatory function and bruxism, or personality factors which influence central modulation of the pain experience.

For more information about Behnam Aghabeigi visit here : http://behnamaghabeigi.co.uk/research–publications.html